【XML配置文件读取】使用jdom读取XML配置文件信息

在项目中我们经常需要将配置信息写在配置文件中，而XML配置文件是常用的格式。

下面将介绍如何通过jdom来读取xml配置文件信息。

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配置文件信息

<?xml version="1.0" encoding="UTF-8"?>
<config>
    <base-config>
	     <stringValue>Hello world</stringValue>
		 <integerValue>8</integerValue>
		 <longValue>32768</longValue>
	</base-config>
	
	<books>
        <book id="111"> 
            <name>Java 编程</name>
			<price>33</price>            
        </book>
        <book id="222">
            <name>Spring学习指南</name>
            <price>55</price>
        </book>
    </books>
      
    <computers>
        <computer type="dell" size="14寸" />
        <computer type="thinkpad" size="16寸" />
        <computer type="apple" size="22寸" />
    </computers>
</config>

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需要的Jar包（MAVEN给出）

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完整的POM文件

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<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.ll</groupId>
	<artifactId>myThreadStudy</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>myThreadStudy</name>
	<url>http://maven.apache.org</url>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<junitVersion>3.8.1</junitVersion>
		<commons-io-Version>2.4</commons-io-Version>
		<jaxenVersion>1.1.1</jaxenVersion>
		<jdomVersion>1.1</jdomVersion>
		<log4jVersion>1.2.17</log4jVersion>
	</properties>

	<dependencies>
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>${junitVersion}</version>
			<scope>test</scope>
		</dependency>

		<dependency>
			<groupId>commons-io</groupId>
			<artifactId>commons-io</artifactId>
			<version>${commons-io-Version}</version>
		</dependency>
		<dependency>
			<groupId>org.jdom</groupId>
			<artifactId>jdom</artifactId>
			<version>${jdomVersion}</version>
		</dependency>
		<dependency>
			<groupId>log4j</groupId>
			<artifactId>log4j</artifactId>
			<version>${log4jVersion}</version>
		</dependency>
		<dependency>
            <groupId>jaxen</groupId>
            <artifactId>jaxen</artifactId>
            <version>${jaxenVersion}</version>
        </dependency>
	</dependencies>

	<build>
		<defaultGoal>install</defaultGoal>

		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>2.5.1</version>
				<configuration>
					<source>1.7</source>
					<target>1.7</target>
					<encoding>UTF-8</encoding>  <!-- “编码 GBK 的不可映射字符”问题的解决 -->
				</configuration>
			</plugin>
		</plugins>
	</build>

</project>

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通用的XML操作类（XMLOperatorUtils.java）

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package com.ll.myThreadStudy.MyThread;

import java.util.List;

import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.xpath.XPath;

public class XMLOperatorUtils {

	public static String getElementAttributeStringValue(Element element,
			String AttributeName) {
		try {
			return element.getAttributeValue(AttributeName);
		} catch (Exception e) {
			return null;
		}
	}

	public static Integer getElementAttributeIntegerValue(Element element,
			String AttributeName) {
		try {
			return Integer.parseInt(getElementAttributeStringValue(element,
					AttributeName));
		} catch (Exception e) {
			return -1;
		}
	}

	public static Long getElementAttributeLongValue(Element element,
			String AttributeName) {
		try {
			return Long.parseLong(getElementAttributeStringValue(element,
					AttributeName));
		} catch (Exception e) {
			return -1l;
		}
	}

	public static Boolean getElementAttributeBooleanValue(Element element,
			String AttributeName) {
		try {
			return Boolean.parseBoolean(getElementAttributeStringValue(element,
					AttributeName));
		} catch (Exception e) {
			return false;
		}
	}

	public static String getElementTextStringValueFromRoot(Element rootEle,
			String path) {
		try {
			return ((Element) getSingleNode(rootEle, path)).getTextTrim();
		} catch (Exception e) {
			return null;
		}
	}

	public static Integer getElementTextIntegerValueFromRoot(Element rootEle,
			String path) {
		try {
			return Integer.parseInt(getElementTextStringValueFromRoot(rootEle,
					path));
		} catch (Exception e) {
			return -1;
		}
	}

	public static Long getElementTextLongValueFromRoot(Element rootEle,
			String path) {
		try {
			return Long.parseLong(getElementTextStringValueFromRoot(rootEle,
					path));
		} catch (Exception e) {
			return -1l;
		}
	}

	public static Boolean getElementTextBooleanValueFromRoot(Element rootEle,
			String path) {
		try {
			return Boolean.parseBoolean(getElementTextStringValueFromRoot(
					rootEle, path));
		} catch (Exception e) {
			return false;
		}
	}

	public static String getElementTextStringValueByElement(Element element,
			String childName) {
		try {
			return element.getChildText(childName);
		} catch (Exception e) {
			return null;
		}
	}

	protected static Integer getElementTextIntegerValueByElement(
			Element element, String childName) {
		try {
			return Integer.parseInt(getElementTextStringValueByElement(element,
					childName));
		} catch (Exception e) {
			return -1;
		}
	}

	protected static Long getElementTextLongValueByElement(Element element,
			String childName) {
		try {
			return Long.parseLong(getElementTextStringValueByElement(element,
					childName));
		} catch (Exception e) {
			return -1l;
		}
	}

	protected static Boolean getElementTextBooleanValueByElement(
			Element element, String childName) {
		try {
			return Boolean.parseBoolean(getElementTextStringValueByElement(
					element, childName));
		} catch (Exception e) {
			return false;
		}
	}

	protected static Object getSingleNode(Element rootEle, String path)
			throws JDOMException {
		return XPath.selectSingleNode(rootEle, path);
	}

	@SuppressWarnings("rawtypes")
	protected static List getNodes(Element rootEle, String path)
			throws JDOMException {
		return XPath.selectNodes(rootEle, path);
	}
}

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读取配置文件到Java POJO

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package com.ll.myThreadStudy.MyThread;

import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.apache.log4j.Logger;
import org.jdom.Element;
import org.jdom.input.SAXBuilder;
import org.jdom.xpath.XPath;

public class XmlToConfigVO {
    private static Logger logger = Logger.getLogger(XmlToConfigVO.class);

    public static MyConfigVo getLogSystemConfigVO(String fileName) {
        try {
            Element rootEle = new SAXBuilder().build(new File(fileName))
                    .getRootElement();
            MyConfigVo myConfigVo = new MyConfigVo();
            
            //获取单个节点值的内容
            myConfigVo.setStringValue(XMLOperatorUtils
                    .getElementTextStringValueFromRoot(rootEle,
                            "/config/base-config/stringValue"));
            myConfigVo.setIntegerValue(XMLOperatorUtils
                    .getElementTextIntegerValueFromRoot(rootEle,
                            "/config/base-config/integerValue"));
            myConfigVo.setLongValue(XMLOperatorUtils
                    .getElementTextLongValueFromRoot(rootEle,
                            "/config/base-config/longValue"));
            
            //获取多个节点值
            HashMap<Integer, BookVo> booksMap = new HashMap<Integer, BookVo>();
            for (Object element : XPath.selectNodes(rootEle,"/config/books/book")) {
            	BookVo book = new BookVo();
            	book.setId(XMLOperatorUtils.getElementAttributeIntegerValue((Element) element,"id"));
            	book.setName(XMLOperatorUtils.getElementTextStringValueByElement((Element) element,"name"));
            	book.setPrice(XMLOperatorUtils.getElementTextLongValueByElement((Element) element,"price"));
            	booksMap.put(book.getId(),book);
            }
            myConfigVo.setBooksMap(booksMap);
            
            List<ComputerVo> computerList= new ArrayList<ComputerVo>();
            for (Object element : XPath.selectNodes(rootEle,"/config/computers/computer")) {
            	ComputerVo computer = new ComputerVo();
            	computer.setType(XMLOperatorUtils.getElementAttributeStringValue((Element) element, "type"));
            	computer.setSize(XMLOperatorUtils.getElementAttributeStringValue((Element) element,"size"));
            	computerList.add(computer);
            }
            myConfigVo.setComputerList(computerList);
            return myConfigVo;
        } catch (Exception e) {
            logger.error(e);
        }
        return null;
    }

}

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完整程序

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package com.ll.myThreadStudy.MyThread;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

public class MyConfigVo {
	private String stringValue;
	private Integer integerValue;
	private Long longValue;
	private HashMap<Integer, BookVo> booksMap = new HashMap<Integer, BookVo>();
	private List<ComputerVo> computerList = new ArrayList<ComputerVo>();

	public String getStringValue() {
		return stringValue;
	}

	public void setStringValue(String stringValue) {
		this.stringValue = stringValue;
	}

	public Integer getIntegerValue() {
		return integerValue;
	}

	public void setIntegerValue(Integer integerValue) {
		this.integerValue = integerValue;
	}

	public Long getLongValue() {
		return longValue;
	}

	public void setLongValue(Long longValue) {
		this.longValue = longValue;
	}

	public HashMap<Integer, BookVo> getBooksMap() {
		return booksMap;
	}

	public void setBooksMap(HashMap<Integer, BookVo> booksMap) {
		this.booksMap = booksMap;
	}

	public List<ComputerVo> getComputerList() {
		return computerList;
	}

	public void setComputerList(List<ComputerVo> computerList) {
		this.computerList = computerList;
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result
				+ ((booksMap == null) ? 0 : booksMap.hashCode());
		result = prime * result
				+ ((computerList == null) ? 0 : computerList.hashCode());
		result = prime * result
				+ ((integerValue == null) ? 0 : integerValue.hashCode());
		result = prime * result
				+ ((longValue == null) ? 0 : longValue.hashCode());
		result = prime * result
				+ ((stringValue == null) ? 0 : stringValue.hashCode());
		return result;
	}

	@Override
	public String toString() {
		return "MyConfigVo [stringValue=" + stringValue + ", integerValue="
				+ integerValue + ", longValue=" + longValue + ", booksMap="
				+ booksMap + ", computerList=" + computerList + "]";
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		MyConfigVo other = (MyConfigVo) obj;
		if (booksMap == null) {
			if (other.booksMap != null)
				return false;
		} else if (!booksMap.equals(other.booksMap))
			return false;
		if (computerList == null) {
			if (other.computerList != null)
				return false;
		} else if (!computerList.equals(other.computerList))
			return false;
		if (integerValue == null) {
			if (other.integerValue != null)
				return false;
		} else if (!integerValue.equals(other.integerValue))
			return false;
		if (longValue == null) {
			if (other.longValue != null)
				return false;
		} else if (!longValue.equals(other.longValue))
			return false;
		if (stringValue == null) {
			if (other.stringValue != null)
				return false;
		} else if (!stringValue.equals(other.stringValue))
			return false;
		return true;
	}

}

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package com.ll.myThreadStudy.MyThread;

public class ComputerVo {
	private String type;
	private String size;

	public String getType() {
		return type;
	}

	public void setType(String type) {
		this.type = type;
	}

	public String getSize() {
		return size;
	}

	public void setSize(String size) {
		this.size = size;
	}

	@Override
	public String toString() {
		return "ComputerVo [type=" + type + ", size=" + size + "]";
	}

}

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package com.ll.myThreadStudy.MyThread;

public class BookVo {
	private Integer id;
	private String name;
	private Long price;

	public Integer getId() {
		return id;
	}

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

	public String getName() {
		return name;
	}

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

	public Long getPrice() {
		return price;
	}

	public void setPrice(Long price) {
		this.price = price;
	}

	@Override
	public String toString() {
		return "BookVo [id=" + id + ", name=" + name + ", price=" + price + "]";
	}

}

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测试文件

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package com.ll.myThreadStudy.MyThread;

public class Main {
	public static void main(String args[]) {
		MyConfigVo myConfigVo = XmlToConfigVO.getLogSystemConfigVO("d:\\myConfig.xml");
		System.out.println(myConfigVo);
	}

}

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测试结果

来自为知笔记(Wiz)

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