Document对象如何转成InputStream

Question

我想读个xml，然后对该xml做些修改后再转成InputStream
请问该怎么实现啊？？

Answer 1

是用JDOM读写XML文件吗，给你两段代码，参考一下吧
package com.bjsxt.drp.util;import java.io.IOException;
import java.util.Iterator;
import java.util.List;import org.jdom.Document;
import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;
import org.jdom.xpath.XPath;
/**读XML文件
 *<?xml version="1.0" encoding="UTF-8"?>
 * <config>
 * <jdbc>
 * <driver-class-name>oracle.jdbc.driver.OracleDriver</driver-class-name>
 * <url>jdbc:oracle:thin:@127.0.0.1:1521:ORACLE9</url>
 * <user-name>drp</user-name>
 * <password>drp</password>
 * </jdbc>
 * <beans>
 * <bean id="com.bjsxt.drp.basedata.dao.ItemDao" class="com.bjsxt.drp.basedata.dao.ItemDao4OracleImpl"/>
 * <bean id="com.bjsxt.drp.flowcard.dao.FlowCardDao" class="com.bjsxt.drp.flowcard.dao.impl.FlowCardDao4OracleImpl"/>
 * </beans>
 * </config>
 */
public class ConfigReader {

private static final String CONFIG_FILE_NAME="drp-config.xml";  private static ConfigReader instance = new ConfigReader();

private ConfigReader() {
SAXBuilder sb = new SAXBuilder();
try {
Document doc = sb.build(Thread.currentThread().getContextClassLoader().getResourceAsStream(CONFIG_FILE_NAME));
Element rootElt = doc.getRootElement();
Element driverClassNameElt = (Element)XPath.selectSingleNode(rootElt, "//config/jdbc/driver-class-name");
System.out.println("driverClassName=" + driverClassNameElt.getText()); 

Element urlElt = (Element)XPath.selectSingleNode(rootElt, "//config/jdbc/url");
System.out.println("url=" + urlElt.getText());

Element userNameElt = (Element)XPath.selectSingleNode(rootElt, "//config/jdbc/user-name");
System.out.println("username=" + userNameElt.getText()); Element passwordElt = (Element)XPath.selectSingleNode(rootElt, "//config/jdbc/password");
System.out.println("password=" + passwordElt.getText());

List beanList = XPath.selectNodes(rootElt, "//config/beans/bean");
for (Iterator iter=beanList.iterator(); iter.hasNext();) {
Element beanElt = (Element)iter.next();
System.out.println("id=" + beanElt.getAttributeValue("id"));
System.out.println("class=" + beanElt.getAttributeValue("class"));
}
} catch (JDOMException e) {
// TODO Auto-generated catch block
e.printStackTrace();
throw new java.lang.RuntimeException();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
throw new java.lang.RuntimeException();
}
}

public static ConfigReader getInstance() {
return instance;
}

public static void main(String[] args) {
ConfigReader.getInstance();
}
}
package com.bjsxt.drp.util;import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;import org.jdom.Document;
import org.jdom.Element;
import org.jdom.output.Format;
import org.jdom.output.XMLOutputter;public class XmlWriter { /**创建XML文件
 * <items>
 *  <item>
 *  <id>6</id>
 *  <name>吉林省</name>
 *      </item>
 *  <item>
 *  <id>7</id>
 *  <name>辽宁省</name>
 *      </item>
 *  <item>
 *  <id>8</id>
 *  <name>黑龙江</name>
 *      </item>
 * </items>
 */
public static void main(String[] args) {
Element rootElt = new Element("items");

Element itemElt = new Element("item");

Element idElt = new Element("id");
idElt.addContent("6");

Element nameElt = new Element("name");
nameElt.addContent("吉林省");

itemElt.addContent(idElt);
itemElt.addContent(nameElt);

rootElt.addContent(itemElt);

Document doc = new Document(rootElt);

XMLOutputter out = new XMLOutputter();
out.setFormat(Format.getCompactFormat().setEncoding("GBK"));

String xmlString = out.outputString(doc);//转换为字符串
System.out.println(xmlString);

try {
out.output(doc, new FileOutputStream("c:/testxml.xml"));
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}}