spring自定义schema学习

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一、前言

1. 最近在学习dubbo，里边很多如provider、consumer、registry的配置都是通过spring自定义Schema来实现的，为此，我也学习下如何自定义Schema。

2.学习目标

完成自定义一个shema名称为test，节点名为user的例子。

二、准备内容

1.编写java bean

2.编写xsd配置文件

3.编写spring.handlers和spring.schmas

4.编写applicationContext.xml

5.编写NamespaceHandler和BeanDefinitionParser

三、晒代码

1.工程目录结构

2.java bean

 package com.cnblogs.ericlin.spring;

 public class User {
     private String id;
     private String name;
     private String sex;
     private int age;

     public String getId() {
         return id;
     }

     public void setId(String id) {
         this.id = id;
     }

     public String getName() {
         return name;
     }

     public void setName(String name) {
         this.name = name;
     }

     public String getSex() {
         return sex;
     }

     public void setSex(String sex) {
         this.sex = sex;
     }

     public int getAge() {
         return age;
     }

     public void setAge(int age) {
         this.age = age;
     }
 }

3.xsd文件

 <?xml version="1.0" encoding="UTF-8" standalone="no" ?>
 <xsd:schema xmlns="http://www.cnblogs.com/eric-lin/schema/user"
     xmlns:xsd="http://www.w3.org/2001/XMLSchema"
     xmlns:beans="http://www.springframework.org/schema/beans"
     xmlns:tool="http://www.springframework.org/schema/tool"
     targetNamespace="http://www.cnblogs.com/eric-lin/schema/user"
     elementFormDefault="qualified" attributeFormDefault="unqualified">

     <xsd:import namespace="http://www.springframework.org/schema/beans" />
     <xsd:import namespace="http://www.springframework.org/schema/tool" />

     <xsd:element name="user">
         <xsd:complexType>
             <xsd:complexContent>
                 <xsd:extension base="beans:identifiedType">
                     <xsd:attribute name="name" type="xsd:string">
                         <xsd:annotation>
                             <xsd:documentation>姓名</xsd:documentation>
                         </xsd:annotation>
                     </xsd:attribute>

                     <xsd:attribute name="sex" type="xsd:string">
                         <xsd:annotation>
                             <xsd:documentation>性别</xsd:documentation>
                         </xsd:annotation>
                     </xsd:attribute>

                     <xsd:attribute name="age" type="xsd:int">
                         <xsd:annotation>
                             <xsd:documentation>年龄</xsd:documentation>
                         </xsd:annotation>
                     </xsd:attribute>
                 </xsd:extension>
             </xsd:complexContent>
         </xsd:complexType>
     </xsd:element>
 </xsd:schema>

4.spring.handlers文件内容

http\://www.cnblogs.com/eric-lin/schema/user=com.cnblogs.ericlin.spring.schema.UserNamespaceHandler

5.spring.schemas文件内容

http\://www.cnblogs.com/eric-lin/schema/user/user.xsd=META-INF/user.xsd

6.applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:test="http://www.cnblogs.com/eric-lin/schema/user"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
    http://www.cnblogs.com/eric-lin/schema/user
    http://www.cnblogs.com/eric-lin/schema/user/user.xsd">

    <test:user id="eric" name="123" sex="male" age="28" />

</beans>   

7.NamespaceHandler

package com.cnblogs.ericlin.spring.schema;

import org.springframework.beans.factory.xml.NamespaceHandlerSupport;

public class UserNamespaceHandler extends NamespaceHandlerSupport {

    public void init() {
        registerBeanDefinitionParser("user", new UserBeanDefinitionParser());
    }
}

8.BeanDefinitionParser

package com.cnblogs.ericlin.spring.schema;

import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.xml.AbstractSingleBeanDefinitionParser;
import org.w3c.dom.Element;

import com.cnblogs.ericlin.spring.User;

public class UserBeanDefinitionParser extends AbstractSingleBeanDefinitionParser {

    @Override
    protected Class<?> getBeanClass(Element element) {
        return User.class;
    }

    @Override
    protected void doParse(Element element, BeanDefinitionBuilder bean) {
        String id = element.getAttribute("id");
        String name = element.getAttribute("name");
        String sex = element.getAttribute("sex");
        int age = Integer.parseInt(element.getAttribute("age"));

        bean.addPropertyValue("id", id);
        bean.addPropertyValue("name", name);
        bean.addPropertyValue("sex", sex);
        bean.addPropertyValue("age", age);
    }
}

9测试类

package com.cnglogs.ericlin.spring;

import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.cnblogs.ericlin.spring.User;

public class TestSpringSchema {

    @SuppressWarnings("resource")
    @Test
    public void test() {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");

        User user = (User) context.getBean("eric");
        System.out.println(user.getId());
        System.out.println(user.getName());
        System.out.println(user.getSex());
        System.out.println(user.getAge());
    }
}

自此，自定义spring shema例子完成。