hbase协处理器编码实例

Observer协处理器通常在一个特定的事件（诸如Get或Put）之前或之后发生，相当于RDBMS中的触发器。Endpoint协处理器则类似于RDBMS中的存储过程，因为它可以让你在RegionServer上对数据执行自定义计算，而不是在客户端上执行计算。

本文是以上两者的简单实例，使用的环境：环境 jdk1.8 hadoop2.6.5 hbase1.2.4。

1、Endpoint实例 
1> 编写适用于protobuf的proto文件，如下，尽量不要带注释，因为编译时可能出现乱码

option java_package = "com.endpoint.test";
option java_outer_classname = "Sum";
option java_generic_services = true;
option java_generate_equals_and_hash = true;
option optimize_for = SPEED;

message SumRequest {
    required string family = 1;
    required string column = 2;
}
message SumResponse {
    required int64 sum = 1 [default = 0];
}
service SumService {
    rpc getSum(SumRequest)
        returns (SumResponse);
}

2> 编译上面的proto文件
使用protoc程序进行编译，linux下或者windows均可，protoc程序可以直接从github下载:https://github.com/google/protobuf/releases，也可以自己编译生成，参见protobuf的编译安装

注意，编译的版本要与hadoop以及hbase使用的版本相同，或者略高，但最好不要过高，hadoop2.6.5 hbase1.2.4使用的都是protobuf2.5.0的版本，写此篇文章时的最新版为3.1.0

（高版本必须指定syntax，例如proto3的syntax在第一行非空白非注释行，必须写：syntax = "proto3"，字段规则移除了 “required”，并把 “optional” 改名为 “singular”,移除了 default 选项。可搜索Protobuf 的 proto3 与 proto2 的区别进行了解。）下载的话选择带win或linux的版本，这是编译好的版本。有很多带具体语言的版本，是一些具体某种语言的发行版源码包。为了与hbase以及hadoop统一起来，此处用的是protoc-2.5.0-win32.zip。

解压文件：

使用windows命令行进入上面的目录，执行以下命令即可：

protoc.exe sum1.proto --java_out=./

高版本有编译好的适用于linux下的protoc程序文件，低版本没有。在linux下执行以下命令：

protoc sum.proto --java_out=./

结果都一样，生成的代码参见折叠部分，有很多，因为上面文件中指定java_outer_classname = "Sum"，所以会生成Sum类，将这个类引入到项目中，注意项目的包名称与上面文件中指定（option java_package = "com.endpoint.test"）的名称要一致。

 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: sumcode.proto

 package com.endpoint.test;

 public final class Sum {
   private Sum() {}
   public static void registerAllExtensions(
       com.google.protobuf.ExtensionRegistry registry) {
   }
   public interface SumRequestOrBuilder
       extends com.google.protobuf.MessageOrBuilder {

     // required string family = 1;
     /**
      * <code>required string family = 1;</code>
      */
     boolean hasFamily();
     /**
      * <code>required string family = 1;</code>
      */
     java.lang.String getFamily();
     /**
      * <code>required string family = 1;</code>
      */
     com.google.protobuf.ByteString
         getFamilyBytes();

     // required string column = 2;
     /**
      * <code>required string column = 2;</code>
      */
     boolean hasColumn();
     /**
      * <code>required string column = 2;</code>
      */
     java.lang.String getColumn();
     /**
      * <code>required string column = 2;</code>
      */
     com.google.protobuf.ByteString
         getColumnBytes();
   }
   /**
    * Protobuf type {@code SumRequest}
    */
   public static final class SumRequest extends
       com.google.protobuf.GeneratedMessage
       implements SumRequestOrBuilder {
     // Use SumRequest.newBuilder() to construct.
     private SumRequest(com.google.protobuf.GeneratedMessage.Builder<?> builder) {
       super(builder);
       this.unknownFields = builder.getUnknownFields();
     }
     private SumRequest(boolean noInit) { this.unknownFields = com.google.protobuf.UnknownFieldSet.getDefaultInstance(); }

     private static final SumRequest defaultInstance;
     public static SumRequest getDefaultInstance() {
       return defaultInstance;
     }

     public SumRequest getDefaultInstanceForType() {
       return defaultInstance;
     }

     private final com.google.protobuf.UnknownFieldSet unknownFields;
     @java.lang.Override
     public final com.google.protobuf.UnknownFieldSet
         getUnknownFields() {
       return this.unknownFields;
     }
     private SumRequest(
         com.google.protobuf.CodedInputStream input,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws com.google.protobuf.InvalidProtocolBufferException {
       initFields();
       int mutable_bitField0_ = 0;
       com.google.protobuf.UnknownFieldSet.Builder unknownFields =
           com.google.protobuf.UnknownFieldSet.newBuilder();
       try {
         boolean done = false;
         while (!done) {
           int tag = input.readTag();
           switch (tag) {
             case 0:
               done = true;
               break;
             default: {
               if (!parseUnknownField(input, unknownFields,
                                      extensionRegistry, tag)) {
                 done = true;
               }
               break;
             }
             case 10: {
               bitField0_ |= 0x00000001;
               family_ = input.readBytes();
               break;
             }
             case 18: {
               bitField0_ |= 0x00000002;
               column_ = input.readBytes();
               break;
             }
           }
         }
       } catch (com.google.protobuf.InvalidProtocolBufferException e) {
         throw e.setUnfinishedMessage(this);
       } catch (java.io.IOException e) {
         throw new com.google.protobuf.InvalidProtocolBufferException(
             e.getMessage()).setUnfinishedMessage(this);
       } finally {
         this.unknownFields = unknownFields.build();
         makeExtensionsImmutable();
       }
     }
     public static final com.google.protobuf.Descriptors.Descriptor
         getDescriptor() {
       return com.endpoint.test.Sum.internal_static_SumRequest_descriptor;
     }

     protected com.google.protobuf.GeneratedMessage.FieldAccessorTable
         internalGetFieldAccessorTable() {
       return com.endpoint.test.Sum.internal_static_SumRequest_fieldAccessorTable
           .ensureFieldAccessorsInitialized(
               com.endpoint.test.Sum.SumRequest.class, com.endpoint.test.Sum.SumRequest.Builder.class);
     }

     public static com.google.protobuf.Parser<SumRequest> PARSER =
         new com.google.protobuf.AbstractParser<SumRequest>() {
       public SumRequest parsePartialFrom(
           com.google.protobuf.CodedInputStream input,
           com.google.protobuf.ExtensionRegistryLite extensionRegistry)
           throws com.google.protobuf.InvalidProtocolBufferException {
         return new SumRequest(input, extensionRegistry);
       }
     };

     @java.lang.Override
     public com.google.protobuf.Parser<SumRequest> getParserForType() {
       return PARSER;
     }

     private int bitField0_;
     // required string family = 1;
     public static final int FAMILY_FIELD_NUMBER = 1;
     private java.lang.Object family_;
     /**
      * <code>required string family = 1;</code>
      */
     public boolean hasFamily() {
       return ((bitField0_ & 0x00000001) == 0x00000001);
     }
     /**
      * <code>required string family = 1;</code>
      */
     public java.lang.String getFamily() {
       java.lang.Object ref = family_;
       if (ref instanceof java.lang.String) {
         return (java.lang.String) ref;
       } else {
         com.google.protobuf.ByteString bs =
             (com.google.protobuf.ByteString) ref;
         java.lang.String s = bs.toStringUtf8();
         if (bs.isValidUtf8()) {
           family_ = s;
         }
         return s;
       }
     }
     /**
      * <code>required string family = 1;</code>
      */
     public com.google.protobuf.ByteString
         getFamilyBytes() {
       java.lang.Object ref = family_;
       if (ref instanceof java.lang.String) {
         com.google.protobuf.ByteString b =
             com.google.protobuf.ByteString.copyFromUtf8(
                 (java.lang.String) ref);
         family_ = b;
         return b;
       } else {
         return (com.google.protobuf.ByteString) ref;
       }
     }

     // required string column = 2;
     public static final int COLUMN_FIELD_NUMBER = 2;
     private java.lang.Object column_;
     /**
      * <code>required string column = 2;</code>
      */
     public boolean hasColumn() {
       return ((bitField0_ & 0x00000002) == 0x00000002);
     }
     /**
      * <code>required string column = 2;</code>
      */
     public java.lang.String getColumn() {
       java.lang.Object ref = column_;
       if (ref instanceof java.lang.String) {
         return (java.lang.String) ref;
       } else {
         com.google.protobuf.ByteString bs =
             (com.google.protobuf.ByteString) ref;
         java.lang.String s = bs.toStringUtf8();
         if (bs.isValidUtf8()) {
           column_ = s;
         }
         return s;
       }
     }
     /**
      * <code>required string column = 2;</code>
      */
     public com.google.protobuf.ByteString
         getColumnBytes() {
       java.lang.Object ref = column_;
       if (ref instanceof java.lang.String) {
         com.google.protobuf.ByteString b =
             com.google.protobuf.ByteString.copyFromUtf8(
                 (java.lang.String) ref);
         column_ = b;
         return b;
       } else {
         return (com.google.protobuf.ByteString) ref;
       }
     }

     private void initFields() {
       family_ = "";
       column_ = "";
     }
     private byte memoizedIsInitialized = -1;
     public final boolean isInitialized() {
       byte isInitialized = memoizedIsInitialized;
       if (isInitialized != -1) return isInitialized == 1;

       if (!hasFamily()) {
         memoizedIsInitialized = 0;
         return false;
       }
       if (!hasColumn()) {
         memoizedIsInitialized = 0;
         return false;
       }
       memoizedIsInitialized = 1;
       return true;
     }

     public void writeTo(com.google.protobuf.CodedOutputStream output)
                         throws java.io.IOException {
       getSerializedSize();
       if (((bitField0_ & 0x00000001) == 0x00000001)) {
         output.writeBytes(1, getFamilyBytes());
       }
       if (((bitField0_ & 0x00000002) == 0x00000002)) {
         output.writeBytes(2, getColumnBytes());
       }
       getUnknownFields().writeTo(output);
     }

     private int memoizedSerializedSize = -1;
     public int getSerializedSize() {
       int size = memoizedSerializedSize;
       if (size != -1) return size;

       size = 0;
       if (((bitField0_ & 0x00000001) == 0x00000001)) {
         size += com.google.protobuf.CodedOutputStream
           .computeBytesSize(1, getFamilyBytes());
       }
       if (((bitField0_ & 0x00000002) == 0x00000002)) {
         size += com.google.protobuf.CodedOutputStream
           .computeBytesSize(2, getColumnBytes());
       }
       size += getUnknownFields().getSerializedSize();
       memoizedSerializedSize = size;
       return size;
     }

     private static final long serialVersionUID = 0L;
     @java.lang.Override
     protected java.lang.Object writeReplace()
         throws java.io.ObjectStreamException {
       return super.writeReplace();
     }

     @java.lang.Override
     public boolean equals(final java.lang.Object obj) {
       if (obj == this) {
        return true;
       }
       if (!(obj instanceof com.endpoint.test.Sum.SumRequest)) {
         return super.equals(obj);
       }
       com.endpoint.test.Sum.SumRequest other = (com.endpoint.test.Sum.SumRequest) obj;

       boolean result = true;
       result = result && (hasFamily() == other.hasFamily());
       if (hasFamily()) {
         result = result && getFamily()
             .equals(other.getFamily());
       }
       result = result && (hasColumn() == other.hasColumn());
       if (hasColumn()) {
         result = result && getColumn()
             .equals(other.getColumn());
       }
       result = result &&
           getUnknownFields().equals(other.getUnknownFields());
       return result;
     }

     private int memoizedHashCode = 0;
     @java.lang.Override
     public int hashCode() {
       if (memoizedHashCode != 0) {
         return memoizedHashCode;
       }
       int hash = 41;
       hash = (19 * hash) + getDescriptorForType().hashCode();
       if (hasFamily()) {
         hash = (37 * hash) + FAMILY_FIELD_NUMBER;
         hash = (53 * hash) + getFamily().hashCode();
       }
       if (hasColumn()) {
         hash = (37 * hash) + COLUMN_FIELD_NUMBER;
         hash = (53 * hash) + getColumn().hashCode();
       }
       hash = (29 * hash) + getUnknownFields().hashCode();
       memoizedHashCode = hash;
       return hash;
     }

     public static com.endpoint.test.Sum.SumRequest parseFrom(
         com.google.protobuf.ByteString data)
         throws com.google.protobuf.InvalidProtocolBufferException {
       return PARSER.parseFrom(data);
     }
     public static com.endpoint.test.Sum.SumRequest parseFrom(
         com.google.protobuf.ByteString data,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws com.google.protobuf.InvalidProtocolBufferException {
       return PARSER.parseFrom(data, extensionRegistry);
     }
     public static com.endpoint.test.Sum.SumRequest parseFrom(byte[] data)
         throws com.google.protobuf.InvalidProtocolBufferException {
       return PARSER.parseFrom(data);
     }
     public static com.endpoint.test.Sum.SumRequest parseFrom(
         byte[] data,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws com.google.protobuf.InvalidProtocolBufferException {
       return PARSER.parseFrom(data, extensionRegistry);
     }
     public static com.endpoint.test.Sum.SumRequest parseFrom(java.io.InputStream input)
         throws java.io.IOException {
       return PARSER.parseFrom(input);
     }
     public static com.endpoint.test.Sum.SumRequest parseFrom(
         java.io.InputStream input,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws java.io.IOException {
       return PARSER.parseFrom(input, extensionRegistry);
     }
     public static com.endpoint.test.Sum.SumRequest parseDelimitedFrom(java.io.InputStream input)
         throws java.io.IOException {
       return PARSER.parseDelimitedFrom(input);
     }
     public static com.endpoint.test.Sum.SumRequest parseDelimitedFrom(
         java.io.InputStream input,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws java.io.IOException {
       return PARSER.parseDelimitedFrom(input, extensionRegistry);
     }
     public static com.endpoint.test.Sum.SumRequest parseFrom(
         com.google.protobuf.CodedInputStream input)
         throws java.io.IOException {
       return PARSER.parseFrom(input);
     }
     public static com.endpoint.test.Sum.SumRequest parseFrom(
         com.google.protobuf.CodedInputStream input,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws java.io.IOException {
       return PARSER.parseFrom(input, extensionRegistry);
     }

     public static Builder newBuilder() { return Builder.create(); }
     public Builder newBuilderForType() { return newBuilder(); }
     public static Builder newBuilder(com.endpoint.test.Sum.SumRequest prototype) {
       return newBuilder().mergeFrom(prototype);
     }
     public Builder toBuilder() { return newBuilder(this); }

     @java.lang.Override
     protected Builder newBuilderForType(
         com.google.protobuf.GeneratedMessage.BuilderParent parent) {
       Builder builder = new Builder(parent);
       return builder;
     }
     /**
      * Protobuf type {@code SumRequest}
      */
     public static final class Builder extends
         com.google.protobuf.GeneratedMessage.Builder<Builder>
        implements com.endpoint.test.Sum.SumRequestOrBuilder {
       public static final com.google.protobuf.Descriptors.Descriptor
           getDescriptor() {
         return com.endpoint.test.Sum.internal_static_SumRequest_descriptor;
       }

       protected com.google.protobuf.GeneratedMessage.FieldAccessorTable
           internalGetFieldAccessorTable() {
         return com.endpoint.test.Sum.internal_static_SumRequest_fieldAccessorTable
             .ensureFieldAccessorsInitialized(
                 com.endpoint.test.Sum.SumRequest.class, com.endpoint.test.Sum.SumRequest.Builder.class);
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       // Construct using com.endpoint.test.Sum.SumRequest.newBuilder()
       private Builder() {
         maybeForceBuilderInitialization();
       }

       private Builder(
           com.google.protobuf.GeneratedMessage.BuilderParent parent) {
         super(parent);
         maybeForceBuilderInitialization();
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       private void maybeForceBuilderInitialization() {
         if (com.google.protobuf.GeneratedMessage.alwaysUseFieldBuilders) {
         }
       }
       private static Builder create() {
         return new Builder();
       }

       public Builder clear() {
         super.clear();
         family_ = "";
         bitField0_ = (bitField0_ & ~0x00000001);
         column_ = "";
         bitField0_ = (bitField0_ & ~0x00000002);
         return this;
       }

       public Builder clone() {
         return create().mergeFrom(buildPartial());
       }

       public com.google.protobuf.Descriptors.Descriptor
           getDescriptorForType() {
         return com.endpoint.test.Sum.internal_static_SumRequest_descriptor;
       }

       public com.endpoint.test.Sum.SumRequest getDefaultInstanceForType() {
         return com.endpoint.test.Sum.SumRequest.getDefaultInstance();
       }

       public com.endpoint.test.Sum.SumRequest build() {
         com.endpoint.test.Sum.SumRequest result = buildPartial();
         if (!result.isInitialized()) {
           throw newUninitializedMessageException(result);
         }
         return result;
       }

       public com.endpoint.test.Sum.SumRequest buildPartial() {
         com.endpoint.test.Sum.SumRequest result = new com.endpoint.test.Sum.SumRequest(this);
         int from_bitField0_ = bitField0_;
         int to_bitField0_ = 0;
         if (((from_bitField0_ & 0x00000001) == 0x00000001)) {
           to_bitField0_ |= 0x00000001;
         }
         result.family_ = family_;
         if (((from_bitField0_ & 0x00000002) == 0x00000002)) {
           to_bitField0_ |= 0x00000002;
         }
         result.column_ = column_;
         result.bitField0_ = to_bitField0_;
         onBuilt();
         return result;
       }

       public Builder mergeFrom(com.google.protobuf.Message other) {
         if (other instanceof com.endpoint.test.Sum.SumRequest) {
           return mergeFrom((com.endpoint.test.Sum.SumRequest)other);
         } else {
           super.mergeFrom(other);
           return this;
         }
       }

       public Builder mergeFrom(com.endpoint.test.Sum.SumRequest other) {
         if (other == com.endpoint.test.Sum.SumRequest.getDefaultInstance()) return this;
         if (other.hasFamily()) {
           bitField0_ |= 0x00000001;
           family_ = other.family_;
           onChanged();
         }
         if (other.hasColumn()) {
           bitField0_ |= 0x00000002;
           column_ = other.column_;
           onChanged();
         }
         this.mergeUnknownFields(other.getUnknownFields());
         return this;
       }

       public final boolean isInitialized() {
         if (!hasFamily()) {

           return false;
         }
         if (!hasColumn()) {

           return false;
         }
         return true;
       }

       public Builder mergeFrom(
           com.google.protobuf.CodedInputStream input,
           com.google.protobuf.ExtensionRegistryLite extensionRegistry)
           throws java.io.IOException {
         com.endpoint.test.Sum.SumRequest parsedMessage = null;
         try {
           parsedMessage = PARSER.parsePartialFrom(input, extensionRegistry);
         } catch (com.google.protobuf.InvalidProtocolBufferException e) {
           parsedMessage = (com.endpoint.test.Sum.SumRequest) e.getUnfinishedMessage();
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         }
         return this;
       }
       private int bitField0_;

       // required string family = 1;
       private java.lang.Object family_ = "";
       /**
        * <code>required string family = 1;</code>
        */
       public boolean hasFamily() {
         return ((bitField0_ & 0x00000001) == 0x00000001);
       }
       /**
        * <code>required string family = 1;</code>
        */
       public java.lang.String getFamily() {
         java.lang.Object ref = family_;
         if (!(ref instanceof java.lang.String)) {
           java.lang.String s = ((com.google.protobuf.ByteString) ref)
               .toStringUtf8();
           family_ = s;
           return s;
         } else {
           return (java.lang.String) ref;
         }
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       /**
        * <code>required string family = 1;</code>
        */
       public com.google.protobuf.ByteString
           getFamilyBytes() {
         java.lang.Object ref = family_;
         if (ref instanceof String) {
           com.google.protobuf.ByteString b =
               com.google.protobuf.ByteString.copyFromUtf8(
                   (java.lang.String) ref);
           family_ = b;
           return b;
         } else {
           return (com.google.protobuf.ByteString) ref;
         }
       }
       /**
        * <code>required string family = 1;</code>
        */
       public Builder setFamily(
           java.lang.String value) {
         if (value == null) {
     throw new NullPointerException();
   }
   bitField0_ |= 0x00000001;
         family_ = value;
         onChanged();
         return this;
       }
       /**
        * <code>required string family = 1;</code>
        */
       public Builder clearFamily() {
         bitField0_ = (bitField0_ & ~0x00000001);
         family_ = getDefaultInstance().getFamily();
         onChanged();
         return this;
       }
       /**
        * <code>required string family = 1;</code>
        */
       public Builder setFamilyBytes(
           com.google.protobuf.ByteString value) {
         if (value == null) {
     throw new NullPointerException();
   }
   bitField0_ |= 0x00000001;
         family_ = value;
         onChanged();
         return this;
       }

       // required string column = 2;
       private java.lang.Object column_ = "";
       /**
        * <code>required string column = 2;</code>
        */
       public boolean hasColumn() {
         return ((bitField0_ & 0x00000002) == 0x00000002);
       }
       /**
        * <code>required string column = 2;</code>
        */
       public java.lang.String getColumn() {
         java.lang.Object ref = column_;
         if (!(ref instanceof java.lang.String)) {
           java.lang.String s = ((com.google.protobuf.ByteString) ref)
               .toStringUtf8();
           column_ = s;
           return s;
         } else {
           return (java.lang.String) ref;
         }
       }
       /**
        * <code>required string column = 2;</code>
        */
       public com.google.protobuf.ByteString
           getColumnBytes() {
         java.lang.Object ref = column_;
         if (ref instanceof String) {
           com.google.protobuf.ByteString b =
               com.google.protobuf.ByteString.copyFromUtf8(
                   (java.lang.String) ref);
           column_ = b;
           return b;
         } else {
           return (com.google.protobuf.ByteString) ref;
         }
       }
       /**
        * <code>required string column = 2;</code>
        */
       public Builder setColumn(
           java.lang.String value) {
         if (value == null) {
     throw new NullPointerException();
   }
   bitField0_ |= 0x00000002;
         column_ = value;
         onChanged();
         return this;
       }
       /**
        * <code>required string column = 2;</code>
        */
       public Builder clearColumn() {
         bitField0_ = (bitField0_ & ~0x00000002);
         column_ = getDefaultInstance().getColumn();
         onChanged();
         return this;
       }
       /**
        * <code>required string column = 2;</code>
        */
       public Builder setColumnBytes(
           com.google.protobuf.ByteString value) {
         if (value == null) {
     throw new NullPointerException();
   }
   bitField0_ |= 0x00000002;
         column_ = value;
         onChanged();
         return this;
       }

       // @@protoc_insertion_point(builder_scope:SumRequest)
     }

     static {
       defaultInstance = new SumRequest(true);
       defaultInstance.initFields();
     }

     // @@protoc_insertion_point(class_scope:SumRequest)
   }

   public interface SumResponseOrBuilder
       extends com.google.protobuf.MessageOrBuilder {

     // required int64 sum = 1 [default = 0];
     /**
      * <code>required int64 sum = 1 [default = 0];</code>
      */
     boolean hasSum();
     /**
      * <code>required int64 sum = 1 [default = 0];</code>
      */
     long getSum();
   }
   /**
    * Protobuf type {@code SumResponse}
    */
   public static final class SumResponse extends
       com.google.protobuf.GeneratedMessage
       implements SumResponseOrBuilder {
     // Use SumResponse.newBuilder() to construct.
     private SumResponse(com.google.protobuf.GeneratedMessage.Builder<?> builder) {
       super(builder);
       this.unknownFields = builder.getUnknownFields();
     }
     private SumResponse(boolean noInit) { this.unknownFields = com.google.protobuf.UnknownFieldSet.getDefaultInstance(); }

     private static final SumResponse defaultInstance;
     public static SumResponse getDefaultInstance() {
       return defaultInstance;
     }

     public SumResponse getDefaultInstanceForType() {
       return defaultInstance;
     }

     private final com.google.protobuf.UnknownFieldSet unknownFields;
     @java.lang.Override
     public final com.google.protobuf.UnknownFieldSet
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       return this.unknownFields;
     }
     private SumResponse(
         com.google.protobuf.CodedInputStream input,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws com.google.protobuf.InvalidProtocolBufferException {
       initFields();
       int mutable_bitField0_ = 0;
       com.google.protobuf.UnknownFieldSet.Builder unknownFields =
           com.google.protobuf.UnknownFieldSet.newBuilder();
       try {
         boolean done = false;
         while (!done) {
           int tag = input.readTag();
           switch (tag) {
             case 0:
               done = true;
               break;
             default: {
               if (!parseUnknownField(input, unknownFields,
                                      extensionRegistry, tag)) {
                 done = true;
               }
               break;
             }
             case 8: {
               bitField0_ |= 0x00000001;
               sum_ = input.readInt64();
               break;
             }
           }
         }
       } catch (com.google.protobuf.InvalidProtocolBufferException e) {
         throw e.setUnfinishedMessage(this);
       } catch (java.io.IOException e) {
         throw new com.google.protobuf.InvalidProtocolBufferException(
             e.getMessage()).setUnfinishedMessage(this);
       } finally {
         this.unknownFields = unknownFields.build();
         makeExtensionsImmutable();
       }
     }
     public static final com.google.protobuf.Descriptors.Descriptor
         getDescriptor() {
       return com.endpoint.test.Sum.internal_static_SumResponse_descriptor;
     }

     protected com.google.protobuf.GeneratedMessage.FieldAccessorTable
         internalGetFieldAccessorTable() {
       return com.endpoint.test.Sum.internal_static_SumResponse_fieldAccessorTable
           .ensureFieldAccessorsInitialized(
               com.endpoint.test.Sum.SumResponse.class, com.endpoint.test.Sum.SumResponse.Builder.class);
     }

     public static com.google.protobuf.Parser<SumResponse> PARSER =
         new com.google.protobuf.AbstractParser<SumResponse>() {
       public SumResponse parsePartialFrom(
           com.google.protobuf.CodedInputStream input,
           com.google.protobuf.ExtensionRegistryLite extensionRegistry)
           throws com.google.protobuf.InvalidProtocolBufferException {
         return new SumResponse(input, extensionRegistry);
       }
     };

     @java.lang.Override
     public com.google.protobuf.Parser<SumResponse> getParserForType() {
       return PARSER;
     }

     private int bitField0_;
     // required int64 sum = 1 [default = 0];
     public static final int SUM_FIELD_NUMBER = 1;
     private long sum_;
     /**
      * <code>required int64 sum = 1 [default = 0];</code>
      */
     public boolean hasSum() {
       return ((bitField0_ & 0x00000001) == 0x00000001);
     }
     /**
      * <code>required int64 sum = 1 [default = 0];</code>
      */
     public long getSum() {
       return sum_;
     }

     private void initFields() {
       sum_ = 0L;
     }
     private byte memoizedIsInitialized = -1;
     public final boolean isInitialized() {
       byte isInitialized = memoizedIsInitialized;
       if (isInitialized != -1) return isInitialized == 1;

       if (!hasSum()) {
         memoizedIsInitialized = 0;
         return false;
       }
       memoizedIsInitialized = 1;
       return true;
     }

     public void writeTo(com.google.protobuf.CodedOutputStream output)
                         throws java.io.IOException {
       getSerializedSize();
       if (((bitField0_ & 0x00000001) == 0x00000001)) {
         output.writeInt64(1, sum_);
       }
       getUnknownFields().writeTo(output);
     }

     private int memoizedSerializedSize = -1;
     public int getSerializedSize() {
       int size = memoizedSerializedSize;
       if (size != -1) return size;

       size = 0;
       if (((bitField0_ & 0x00000001) == 0x00000001)) {
         size += com.google.protobuf.CodedOutputStream
           .computeInt64Size(1, sum_);
       }
       size += getUnknownFields().getSerializedSize();
       memoizedSerializedSize = size;
       return size;
     }

     private static final long serialVersionUID = 0L;
     @java.lang.Override
     protected java.lang.Object writeReplace()
         throws java.io.ObjectStreamException {
       return super.writeReplace();
     }

     @java.lang.Override
     public boolean equals(final java.lang.Object obj) {
       if (obj == this) {
        return true;
       }
       if (!(obj instanceof com.endpoint.test.Sum.SumResponse)) {
         return super.equals(obj);
       }
       com.endpoint.test.Sum.SumResponse other = (com.endpoint.test.Sum.SumResponse) obj;

       boolean result = true;
       result = result && (hasSum() == other.hasSum());
       if (hasSum()) {
         result = result && (getSum()
             == other.getSum());
       }
       result = result &&
           getUnknownFields().equals(other.getUnknownFields());
       return result;
     }

     private int memoizedHashCode = 0;
     @java.lang.Override
     public int hashCode() {
       if (memoizedHashCode != 0) {
         return memoizedHashCode;
       }
       int hash = 41;
       hash = (19 * hash) + getDescriptorForType().hashCode();
       if (hasSum()) {
         hash = (37 * hash) + SUM_FIELD_NUMBER;
         hash = (53 * hash) + hashLong(getSum());
       }
       hash = (29 * hash) + getUnknownFields().hashCode();
       memoizedHashCode = hash;
       return hash;
     }

     public static com.endpoint.test.Sum.SumResponse parseFrom(
         com.google.protobuf.ByteString data)
         throws com.google.protobuf.InvalidProtocolBufferException {
       return PARSER.parseFrom(data);
     }
     public static com.endpoint.test.Sum.SumResponse parseFrom(
         com.google.protobuf.ByteString data,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws com.google.protobuf.InvalidProtocolBufferException {
       return PARSER.parseFrom(data, extensionRegistry);
     }
     public static com.endpoint.test.Sum.SumResponse parseFrom(byte[] data)
         throws com.google.protobuf.InvalidProtocolBufferException {
       return PARSER.parseFrom(data);
     }
     public static com.endpoint.test.Sum.SumResponse parseFrom(
         byte[] data,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws com.google.protobuf.InvalidProtocolBufferException {
       return PARSER.parseFrom(data, extensionRegistry);
     }
     public static com.endpoint.test.Sum.SumResponse parseFrom(java.io.InputStream input)
         throws java.io.IOException {
       return PARSER.parseFrom(input);
     }
     public static com.endpoint.test.Sum.SumResponse parseFrom(
         java.io.InputStream input,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws java.io.IOException {
       return PARSER.parseFrom(input, extensionRegistry);
     }
     public static com.endpoint.test.Sum.SumResponse parseDelimitedFrom(java.io.InputStream input)
         throws java.io.IOException {
       return PARSER.parseDelimitedFrom(input);
     }
     public static com.endpoint.test.Sum.SumResponse parseDelimitedFrom(
         java.io.InputStream input,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws java.io.IOException {
       return PARSER.parseDelimitedFrom(input, extensionRegistry);
     }
     public static com.endpoint.test.Sum.SumResponse parseFrom(
         com.google.protobuf.CodedInputStream input)
         throws java.io.IOException {
       return PARSER.parseFrom(input);
     }
     public static com.endpoint.test.Sum.SumResponse parseFrom(
         com.google.protobuf.CodedInputStream input,
         com.google.protobuf.ExtensionRegistryLite extensionRegistry)
         throws java.io.IOException {
       return PARSER.parseFrom(input, extensionRegistry);
     }

     public static Builder newBuilder() { return Builder.create(); }
     public Builder newBuilderForType() { return newBuilder(); }
     public static Builder newBuilder(com.endpoint.test.Sum.SumResponse prototype) {
       return newBuilder().mergeFrom(prototype);
     }
     public Builder toBuilder() { return newBuilder(this); }

     @java.lang.Override
     protected Builder newBuilderForType(
         com.google.protobuf.GeneratedMessage.BuilderParent parent) {
       Builder builder = new Builder(parent);
       return builder;
     }
     /**
      * Protobuf type {@code SumResponse}
      */
     public static final class Builder extends
         com.google.protobuf.GeneratedMessage.Builder<Builder>
        implements com.endpoint.test.Sum.SumResponseOrBuilder {
       public static final com.google.protobuf.Descriptors.Descriptor
           getDescriptor() {
         return com.endpoint.test.Sum.internal_static_SumResponse_descriptor;
       }

       protected com.google.protobuf.GeneratedMessage.FieldAccessorTable
           internalGetFieldAccessorTable() {
         return com.endpoint.test.Sum.internal_static_SumResponse_fieldAccessorTable
             .ensureFieldAccessorsInitialized(
                 com.endpoint.test.Sum.SumResponse.class, com.endpoint.test.Sum.SumResponse.Builder.class);
       }

       // Construct using com.endpoint.test.Sum.SumResponse.newBuilder()
       private Builder() {
         maybeForceBuilderInitialization();
       }

       private Builder(
           com.google.protobuf.GeneratedMessage.BuilderParent parent) {
         super(parent);
         maybeForceBuilderInitialization();
       }
       private void maybeForceBuilderInitialization() {
         if (com.google.protobuf.GeneratedMessage.alwaysUseFieldBuilders) {
         }
       }
       private static Builder create() {
         return new Builder();
       }

       public Builder clear() {
         super.clear();
         sum_ = 0L;
         bitField0_ = (bitField0_ & ~0x00000001);
         return this;
       }

       public Builder clone() {
         return create().mergeFrom(buildPartial());
       }

       public com.google.protobuf.Descriptors.Descriptor
           getDescriptorForType() {
         return com.endpoint.test.Sum.internal_static_SumResponse_descriptor;
       }

       public com.endpoint.test.Sum.SumResponse getDefaultInstanceForType() {
         return com.endpoint.test.Sum.SumResponse.getDefaultInstance();
       }

       public com.endpoint.test.Sum.SumResponse build() {
         com.endpoint.test.Sum.SumResponse result = buildPartial();
         if (!result.isInitialized()) {
           throw newUninitializedMessageException(result);
         }
         return result;
       }

       public com.endpoint.test.Sum.SumResponse buildPartial() {
         com.endpoint.test.Sum.SumResponse result = new com.endpoint.test.Sum.SumResponse(this);
         int from_bitField0_ = bitField0_;
         int to_bitField0_ = 0;
         if (((from_bitField0_ & 0x00000001) == 0x00000001)) {
           to_bitField0_ |= 0x00000001;
         }
         result.sum_ = sum_;
         result.bitField0_ = to_bitField0_;
         onBuilt();
         return result;
       }

       public Builder mergeFrom(com.google.protobuf.Message other) {
         if (other instanceof com.endpoint.test.Sum.SumResponse) {
           return mergeFrom((com.endpoint.test.Sum.SumResponse)other);
         } else {
           super.mergeFrom(other);
           return this;
         }
       }

       public Builder mergeFrom(com.endpoint.test.Sum.SumResponse other) {
         if (other == com.endpoint.test.Sum.SumResponse.getDefaultInstance()) return this;
         if (other.hasSum()) {
           setSum(other.getSum());
         }
         this.mergeUnknownFields(other.getUnknownFields());
         return this;
       }

       public final boolean isInitialized() {
         if (!hasSum()) {

           return false;
         }
         return true;
       }

       public Builder mergeFrom(
           com.google.protobuf.CodedInputStream input,
           com.google.protobuf.ExtensionRegistryLite extensionRegistry)
           throws java.io.IOException {
         com.endpoint.test.Sum.SumResponse parsedMessage = null;
         try {
           parsedMessage = PARSER.parsePartialFrom(input, extensionRegistry);
         } catch (com.google.protobuf.InvalidProtocolBufferException e) {
           parsedMessage = (com.endpoint.test.Sum.SumResponse) e.getUnfinishedMessage();
           throw e;
         } finally {
           if (parsedMessage != null) {
             mergeFrom(parsedMessage);
           }
         }
         return this;
       }
       private int bitField0_;

       // required int64 sum = 1 [default = 0];
       private long sum_ ;
       /**
        * <code>required int64 sum = 1 [default = 0];</code>
        */
       public boolean hasSum() {
         return ((bitField0_ & 0x00000001) == 0x00000001);
       }
       /**
        * <code>required int64 sum = 1 [default = 0];</code>
        */
       public long getSum() {
         return sum_;
       }
       /**
        * <code>required int64 sum = 1 [default = 0];</code>
        */
       public Builder setSum(long value) {
         bitField0_ |= 0x00000001;
         sum_ = value;
         onChanged();
         return this;
       }
       /**
        * <code>required int64 sum = 1 [default = 0];</code>
        */
       public Builder clearSum() {
         bitField0_ = (bitField0_ & ~0x00000001);
         sum_ = 0L;
         onChanged();
         return this;
       }

       // @@protoc_insertion_point(builder_scope:SumResponse)
     }

     static {
       defaultInstance = new SumResponse(true);
       defaultInstance.initFields();
     }

     // @@protoc_insertion_point(class_scope:SumResponse)
   }

   /**
    * Protobuf service {@code SumService}
    */
   public static abstract class SumService
       implements com.google.protobuf.Service {
     protected SumService() {}

     public interface Interface {
       /**
        * <code>rpc getSum(.SumRequest) returns (.SumResponse);</code>
        */
       public abstract void getSum(
           com.google.protobuf.RpcController controller,
           com.endpoint.test.Sum.SumRequest request,
           com.google.protobuf.RpcCallback<com.endpoint.test.Sum.SumResponse> done);

     }

     public static com.google.protobuf.Service newReflectiveService(
         final Interface impl) {
       return new SumService() {
         @java.lang.Override
         public  void getSum(
             com.google.protobuf.RpcController controller,
             com.endpoint.test.Sum.SumRequest request,
             com.google.protobuf.RpcCallback<com.endpoint.test.Sum.SumResponse> done) {
           impl.getSum(controller, request, done);
         }

       };
     }

     public static com.google.protobuf.BlockingService
         newReflectiveBlockingService(final BlockingInterface impl) {
       return new com.google.protobuf.BlockingService() {
         public final com.google.protobuf.Descriptors.ServiceDescriptor
             getDescriptorForType() {
           return getDescriptor();
         }

         public final com.google.protobuf.Message callBlockingMethod(
             com.google.protobuf.Descriptors.MethodDescriptor method,
             com.google.protobuf.RpcController controller,
             com.google.protobuf.Message request)
             throws com.google.protobuf.ServiceException {
           if (method.getService() != getDescriptor()) {
             throw new java.lang.IllegalArgumentException(
               "Service.callBlockingMethod() given method descriptor for " +
               "wrong service type.");
           }
           switch(method.getIndex()) {
             case 0:
               return impl.getSum(controller, (com.endpoint.test.Sum.SumRequest)request);
             default:
               throw new java.lang.AssertionError("Can't get here.");
           }
         }

         public final com.google.protobuf.Message
             getRequestPrototype(
             com.google.protobuf.Descriptors.MethodDescriptor method) {
           if (method.getService() != getDescriptor()) {
             throw new java.lang.IllegalArgumentException(
               "Service.getRequestPrototype() given method " +
               "descriptor for wrong service type.");
           }
           switch(method.getIndex()) {
             case 0:
               return com.endpoint.test.Sum.SumRequest.getDefaultInstance();
             default:
               throw new java.lang.AssertionError("Can't get here.");
           }
         }

         public final com.google.protobuf.Message
             getResponsePrototype(
             com.google.protobuf.Descriptors.MethodDescriptor method) {
           if (method.getService() != getDescriptor()) {
             throw new java.lang.IllegalArgumentException(
               "Service.getResponsePrototype() given method " +
               "descriptor for wrong service type.");
           }
           switch(method.getIndex()) {
             case 0:
               return com.endpoint.test.Sum.SumResponse.getDefaultInstance();
             default:
               throw new java.lang.AssertionError("Can't get here.");
           }
         }

       };
     }

     /**
      * <code>rpc getSum(.SumRequest) returns (.SumResponse);</code>
      */
     public abstract void getSum(
         com.google.protobuf.RpcController controller,
         com.endpoint.test.Sum.SumRequest request,
         com.google.protobuf.RpcCallback<com.endpoint.test.Sum.SumResponse> done);

     public static final
         com.google.protobuf.Descriptors.ServiceDescriptor
         getDescriptor() {
       return com.endpoint.test.Sum.getDescriptor().getServices().get(0);
     }
     public final com.google.protobuf.Descriptors.ServiceDescriptor
         getDescriptorForType() {
       return getDescriptor();
     }

     public final void callMethod(
         com.google.protobuf.Descriptors.MethodDescriptor method,
         com.google.protobuf.RpcController controller,
         com.google.protobuf.Message request,
         com.google.protobuf.RpcCallback<
           com.google.protobuf.Message> done) {
       if (method.getService() != getDescriptor()) {
         throw new java.lang.IllegalArgumentException(
           "Service.callMethod() given method descriptor for wrong " +
           "service type.");
       }
       switch(method.getIndex()) {
         case 0:
           this.getSum(controller, (com.endpoint.test.Sum.SumRequest)request,
             com.google.protobuf.RpcUtil.<com.endpoint.test.Sum.SumResponse>specializeCallback(
               done));
           return;
         default:
           throw new java.lang.AssertionError("Can't get here.");
       }
     }

     public final com.google.protobuf.Message
         getRequestPrototype(
         com.google.protobuf.Descriptors.MethodDescriptor method) {
       if (method.getService() != getDescriptor()) {
         throw new java.lang.IllegalArgumentException(
           "Service.getRequestPrototype() given method " +
           "descriptor for wrong service type.");
       }
       switch(method.getIndex()) {
         case 0:
           return com.endpoint.test.Sum.SumRequest.getDefaultInstance();
         default:
           throw new java.lang.AssertionError("Can't get here.");
       }
     }

     public final com.google.protobuf.Message
         getResponsePrototype(
         com.google.protobuf.Descriptors.MethodDescriptor method) {
       if (method.getService() != getDescriptor()) {
         throw new java.lang.IllegalArgumentException(
           "Service.getResponsePrototype() given method " +
           "descriptor for wrong service type.");
       }
       switch(method.getIndex()) {
         case 0:
           return com.endpoint.test.Sum.SumResponse.getDefaultInstance();
         default:
           throw new java.lang.AssertionError("Can't get here.");
       }
     }

     public static Stub newStub(
         com.google.protobuf.RpcChannel channel) {
       return new Stub(channel);
     }

     public static final class Stub extends com.endpoint.test.Sum.SumService implements Interface {
       private Stub(com.google.protobuf.RpcChannel channel) {
         this.channel = channel;
       }

       private final com.google.protobuf.RpcChannel channel;

       public com.google.protobuf.RpcChannel getChannel() {
         return channel;
       }

       public  void getSum(
           com.google.protobuf.RpcController controller,
           com.endpoint.test.Sum.SumRequest request,
           com.google.protobuf.RpcCallback<com.endpoint.test.Sum.SumResponse> done) {
         channel.callMethod(
           getDescriptor().getMethods().get(0),
           controller,
           request,
           com.endpoint.test.Sum.SumResponse.getDefaultInstance(),
           com.google.protobuf.RpcUtil.generalizeCallback(
             done,
             com.endpoint.test.Sum.SumResponse.class,
             com.endpoint.test.Sum.SumResponse.getDefaultInstance()));
       }
     }

     public static BlockingInterface newBlockingStub(
         com.google.protobuf.BlockingRpcChannel channel) {
       return new BlockingStub(channel);
     }

     public interface BlockingInterface {
       public com.endpoint.test.Sum.SumResponse getSum(
           com.google.protobuf.RpcController controller,
           com.endpoint.test.Sum.SumRequest request)
           throws com.google.protobuf.ServiceException;
     }

     private static final class BlockingStub implements BlockingInterface {
       private BlockingStub(com.google.protobuf.BlockingRpcChannel channel) {
         this.channel = channel;
       }

       private final com.google.protobuf.BlockingRpcChannel channel;

       public com.endpoint.test.Sum.SumResponse getSum(
           com.google.protobuf.RpcController controller,
           com.endpoint.test.Sum.SumRequest request)
           throws com.google.protobuf.ServiceException {
         return (com.endpoint.test.Sum.SumResponse) channel.callBlockingMethod(
           getDescriptor().getMethods().get(0),
           controller,
           request,
           com.endpoint.test.Sum.SumResponse.getDefaultInstance());
       }

     }

     // @@protoc_insertion_point(class_scope:SumService)
   }

   private static com.google.protobuf.Descriptors.Descriptor
     internal_static_SumRequest_descriptor;
   private static
     com.google.protobuf.GeneratedMessage.FieldAccessorTable
       internal_static_SumRequest_fieldAccessorTable;
   private static com.google.protobuf.Descriptors.Descriptor
     internal_static_SumResponse_descriptor;
   private static
     com.google.protobuf.GeneratedMessage.FieldAccessorTable
       internal_static_SumResponse_fieldAccessorTable;

   public static com.google.protobuf.Descriptors.FileDescriptor
       getDescriptor() {
     return descriptor;
   }
   private static com.google.protobuf.Descriptors.FileDescriptor
       descriptor;
   static {
     java.lang.String[] descriptorData = {
       "\n\rsumcode.proto\",\n\nSumRequest\022\016\n\006family\030" +
       "\001 \002(\t\022\016\n\006column\030\002 \002(\t\"\035\n\013SumResponse\022\016\n\003" +
       "sum\030\001 \002(\003:\001021\n\nSumService\022#\n\006getSum\022\013.S" +
       "umRequest\032\014.SumResponseB \n\021com.endpoint." +
       "testB\003SumH\001\210\001\001\240\001\001"
     };
     com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner assigner =
       new com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner() {
         public com.google.protobuf.ExtensionRegistry assignDescriptors(
             com.google.protobuf.Descriptors.FileDescriptor root) {
           descriptor = root;
           internal_static_SumRequest_descriptor =
             getDescriptor().getMessageTypes().get(0);
           internal_static_SumRequest_fieldAccessorTable = new
             com.google.protobuf.GeneratedMessage.FieldAccessorTable(
               internal_static_SumRequest_descriptor,
               new java.lang.String[] { "Family", "Column", });
           internal_static_SumResponse_descriptor =
             getDescriptor().getMessageTypes().get(1);
           internal_static_SumResponse_fieldAccessorTable = new
             com.google.protobuf.GeneratedMessage.FieldAccessorTable(
               internal_static_SumResponse_descriptor,
               new java.lang.String[] { "Sum", });
           return null;
         }
       };
     com.google.protobuf.Descriptors.FileDescriptor
       .internalBuildGeneratedFileFrom(descriptorData,
         new com.google.protobuf.Descriptors.FileDescriptor[] {
         }, assigner);
   }

   // @@protoc_insertion_point(outer_class_scope)
 }

2> 编写服务器端的代码

 package com.endpoint.test;

 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.Coprocessor;
 import org.apache.hadoop.hbase.CoprocessorEnvironment;
 import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.coprocessor.CoprocessorException;
 import org.apache.hadoop.hbase.coprocessor.CoprocessorService;
 import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment;
 import org.apache.hadoop.hbase.protobuf.ResponseConverter;
 import org.apache.hadoop.hbase.regionserver.InternalScanner;
 import org.apache.hadoop.hbase.util.Bytes;
 import com.endpoint.test.Sum.SumRequest;
 import com.endpoint.test.Sum.SumResponse;
 import com.endpoint.test.Sum.SumService;
 import com.google.protobuf.RpcCallback;
 import com.google.protobuf.RpcController;
 import com.google.protobuf.Service;

 public class SumEndPoint extends SumService implements Coprocessor,CoprocessorService{

     private RegionCoprocessorEnvironment env;   // 定义环境
     @Override
     public Service getService() {

         return this;
     }

     @Override
     public void start(CoprocessorEnvironment env) throws IOException {
          if (env instanceof RegionCoprocessorEnvironment) {
                 this.env = (RegionCoprocessorEnvironment)env;
             } else {
                 throw new CoprocessorException("no load region");
             }  

     }

     @Override
     public void stop(CoprocessorEnvironment env) throws IOException {

     }

     @Override
     public void getSum(RpcController controller, SumRequest request, RpcCallback<SumResponse> done) {

         // 设置扫描对象
         Scan scan = new Scan();
         scan.addFamily(Bytes.toBytes(request.getFamily()));
         scan.addColumn(Bytes.toBytes(request.getFamily()), Bytes.toBytes(request.getColumn()));  

         // 定义变量
         SumResponse response = null;
         InternalScanner scanner = null;  

         // 扫描每个region，取值后求和
         try {
             scanner = env.getRegion().getScanner(scan);
             List<Cell> results = new ArrayList<Cell>();
             boolean hasMore = false;
             Long sum = 0L;
             do {
                 hasMore = scanner.next(results);
                 for (Cell cell : results) {
                     sum += Long.parseLong(new String(CellUtil.cloneValue(cell)));
                 }
                 results.clear();
             } while (hasMore);
             // 设置返回结果
             response = SumResponse.newBuilder().setSum(sum).build();
         } catch (IOException e) {
             ResponseConverter.setControllerException(controller, e);
         } finally {
             if (scanner != null) {
                 try {
                     scanner.close();
                 } catch (IOException e) {
                     //e.printStackTrace();
                 }
             }
         }
         // 将rpc结果返回给客户端
         done.run(response);  

     }

 }

3> 客户端测试代码

 package com.endpoint.test;

 import java.io.IOException;
 import java.util.Map;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
 import org.apache.hadoop.hbase.client.HTable;
 import org.apache.hadoop.hbase.client.coprocessor.Batch;
 import org.apache.hadoop.hbase.ipc.BlockingRpcCallback;
 import com.endpoint.test.Sum.SumRequest;
 import com.endpoint.test.Sum.SumResponse;
 import com.endpoint.test.Sum.SumService;
 import com.google.protobuf.ServiceException;

 public class TestClient {

     public static void main(String[] args) throws Exception {

             // 配置HBse
             Configuration conf = HBaseConfiguration.create();
             conf.set("hbase.zookeeper.quorum", "master,data1,data2");
             conf.set("hbase.zookeeper.property.clientPort", "2181");
             conf.setLong("hbase.rpc.timeout", 600000);
             System.setProperty("hadoop.home.dir", "C:/hadoopfiles/hadoop-common-2.2.0-bin-master");

             // 建立一个数据库的连接
             Connection conn = ConnectionFactory.createConnection(conf);
             // 获取表
             HTable table = (HTable) conn.getTable(TableName.valueOf("etable"));  

             long sum = 0L;                

             // 设置请求对象
             final SumRequest request = SumRequest.newBuilder().setFamily("cf").setColumn("value").build();  

             try {
                 // 获得返回值
                 Map<byte[], Long> result = table.coprocessorService(SumService.class, null, null,
                         new Batch.Call<SumService, Long>() {  

                             @Override
                             public Long call(SumService service) throws IOException {
                                 BlockingRpcCallback<SumResponse> rpcCallback = new BlockingRpcCallback<SumResponse>();
                                 service.getSum(null, request, rpcCallback);
                                 SumResponse response = (SumResponse) rpcCallback.get();
                                 return response.hasSum() ? response.getSum() : 0L;
                             }
                 });
                 // 将返回值进行迭代相加
                 for (Long v : result.values()) {
                     sum += v;
                 }
                 // 结果输出
                 System.out.println("sum: " + sum);                        

             } catch (ServiceException e) {
                 e.printStackTrace();
             }catch (Throwable e) {
                 e.printStackTrace();
             }
             table.close();
             conn.close();  

     }

 }

System.setProperty("hadoop.home.dir", "C:/hadoopfiles/hadoop-common-2.2.0-bin-master"); 这句代码是防错误用的，不具有实际意义，在hadoop-common-2.2.0-bin-master下建立bin目录放一个winutils.exe文件即可，否则会出现提示“Could not locate executable null\bin\winutils.exe in the Hadoop binaries”

此外，需要在windows下设置一下hosts文件，因为conf.set("hbase.zookeeper.quorum", "master,data1,data2");

4> 使用Endpoint协处理器

将上面的Sum类文件与用于服务端的SumEndPoint 类文件打包上传到服务器

chown hadoop:hadoop datacode.jar
chmod g+w  datacode.jar 

先改一下权限，之后

hadoop fs -copyFromLocal sumtest.jar /input/

下面是要使用协处理器的hbase表

要将协处理器加载到这个表上

disable 'etable'
# 包名.类名|权重 com.endpoint.test.SumEndPoint|100
alter'etable',METHOD =>'table_att','coprocessor' =>'/input/sumcode.jar|com.endpoint.test.SumEndPoint|100'
enable 'etable'

包名.类名|权重 com.endpoint.test.SumEndPoint|100

# 这样也是可以的，但是在集群变换主节点的情况下，不是很好
# alter'etable',METHOD =>'table_att','coprocessor' =>'hdfs://192.168.1.215:9000/input/sumcode.jar|com.endpoint.test.SumEndPoint|100'

此外，值得注意的一点，在集群中，最好在hbase-site.xml中设置以下属性：

<property>
        <name>hbase.coprocessor.abortonerror</name>
        <value>false</value>
</property> 

设置为false目的在于提高容错性，如果这个属性没有设置为false，则在上传的jar包存在错误的情况下，会导致表不能enable或disable，从而导致集群中的这张表无法使用，甚至会影响到其他表。

在windows中的客户端运行客户端的代码，结果如下：

 2、Observer实例
这个是一个二级索引实例，即假定在initialtable表中的数据格式是这样的

row1    E   151
row2    Y   158

在向initialtable表中写入数据时，自动将以下数据写入indextable表作为二级索引，indextable第二列成为indextable的键

Y    158

1> 编写服务端代码

 package com.observer.test;

 import java.io.IOException;
 import java.util.List;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.Durability;
 import org.apache.hadoop.hbase.client.HTableInterface;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.coprocessor.BaseRegionObserver;
 import org.apache.hadoop.hbase.coprocessor.ObserverContext;
 import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment;
 import org.apache.hadoop.hbase.regionserver.wal.WALEdit;
 import org.apache.hadoop.hbase.util.Bytes;

 public class TestObserver extends BaseRegionObserver {
     @Override
     public void postPut(ObserverContext<RegionCoprocessorEnvironment> e, Put put, WALEdit edit, Durability durability)
             throws IOException {
         // indextable作为二级索引表
         HTableInterface table = e.getEnvironment().getTable(TableName.valueOf("indextable"));
         // 获取值
         List<Cell> cellList1 = put.get(Bytes.toBytes("cf"), Bytes.toBytes("name"));
         List<Cell> cellList2 = put.get(Bytes.toBytes("cf"), Bytes.toBytes("value"));
         // 写入数据
         for (Cell cell1 : cellList1) {
             // 原表的列cf:name的值作为indextable的rowkey，添加行
             Put indexPut = new Put(CellUtil.cloneValue(cell1));
             for (Cell cell2 : cellList2) {
                 // 原表的列cf:value的值作为indextable表中列cf:value的值 。
                 indexPut.add(Bytes.toBytes("cf"), Bytes.toBytes("value"), CellUtil.cloneValue(cell2));
             }  

             table.put(indexPut);
         }  

         table.close();
     }

 }

2> 编写客户段代码

 package com.observer.test;

 import java.io.IOException;

 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
 import org.apache.hadoop.hbase.client.HTable;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.util.Bytes;

 public class DataClient {

     public static void main(String[] args) throws IOException {
         //配置
         Configuration conf = HBaseConfiguration.create();
         conf.set("hbase.zookeeper.quorum", "master,data1,data2");
         conf.set("hbase.zookeeper.property.clientPort", "2181");
         //连接
         Connection conn = ConnectionFactory.createConnection(conf);
         HTable table = (HTable) conn.getTable(TableName.valueOf("initialtable"));
         // 写入数据
         Put put = new Put(Bytes.toBytes("row01"));
         put.addColumn(Bytes.toBytes("cf"), Bytes.toBytes("name"), Bytes.toBytes("E"));
         put.addColumn(Bytes.toBytes("cf"), Bytes.toBytes("value"), Bytes.toBytes("151"));
         table.put(put);
         // 关闭资源
         table.close();
         conn.close();  

     }

 }

3> 创建需要的表

4> 加载协处理器
将服务端代码打包上传集群服务器的hdfs上

chown hadoop:hadoop datacode.jar
chmod g+w  datacode.jar
hadoop dfs -put datacode.jar /input/

之后，将协处理器加载到初始表中

disable 'initialtable'
alter'initialtable',METHOD =>'table_att','coprocessor' =>'/input/datacode.jar|com.observer.test.TestObserver|100'
enable 'initialtable'

5> 执行客户端代码，显示结果