java之讀取xml字符串（java如何解析xml字符串）

本文目錄一覽：

• 1、java中如何讀入XML格式的string或硬盤文件？還有怎麼判定一個string的內容為XML格式的？
• 2、java讀取xml文件內容
• 3、在Java中如何讀取XML字符串的元素值

java中如何讀入XML格式的string或硬盤文件？還有怎麼判定一個string的內容為XML格式的？

public class Test {

public static void main(String args[]){

boolean b = false;

try {

FileReader read = new FileReader(“D:/struts.xml”);

BufferedReader br = new BufferedReader(read);

String row;

int i=0;

while((row = br.readLine())!=null){

System.out.println(row);

if(row.substring(0, 5).equals(“?xml”) row.substring(row.length()-2, row.length()).equals(“?”)){

b=true;

}

i++;

}

} catch (FileNotFoundException e) {

e.printStackTrace();

} catch (IOException e){

e.printStackTrace();

}

if(b){

System.out.println(“這是一個xml文件”);

}else

System.out.println(“這不是一個xml文件”);

}

}

運行結果：

?xml version=”1.0″ encoding=”UTF-8″?

!DOCTYPE struts PUBLIC

“-//Apache Software Foundation//DTD Struts Configuration 2.0//EN”

“”

struts

include file=”struts-login.xml” /

include file=”struts-okd.xml” /

include file=”struts-smt.xml” /

/struts

這是一個xml文件

—————————————————-

當我把文件換為test.xml時，運行結果：

01211132abcd

這不是一個xml文件

java讀取xml文件內容

java中不是有個讀取xml文件的類嗎？之間調用那類讀取出來，然後用取節點的方法去取對應節點的里的值。等下給你代碼。

public class ReaderXml {

private static String filename = “E:\\workplace\\readerxml\\bin\\reader\\xml\\reader.xml”;

// private static Config config;

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

//這裡用反射機制

DocumentBuilderFactory domfac=DocumentBuilderFactory.newInstance();

DocumentBuilder dombuilder=domfac.newDocumentBuilder();

//讀取文件流

InputStream is=new FileInputStream(filename);

Document doc=dombuilder.parse(is);

Element root=doc.getDocumentElement();

//獲取所有xml節點

NodeList dbinfo=root.getChildNodes();

if(dbinfo!=null){

for(int i=0;idbinfo.getLength();i++){

//獲取節點判斷

Node db=dbinfo.item(i);

//如果是Hardwares節點，也就是你xml文件的最頂處的節點

if(db.getNodeName().equals(“Hardwares”)){

//獲取第二個節點包含的所有節點

NodeList list=db.getChildNodes();

for(int y=0;ylist.getLength();y++){

Node n=list.item(y);

//如果節點等於Hardware

if(n.getNodeName().equals(“Hardware”)){

//獲取Hardware節點中的所有節點

NodeList CnodeList=n.getChildNodes();

//取出Hardware裏面的所有節點

for(int k=0;kCnodeList.getLength();k++){

//取出節點

Node cn=CnodeList.item(k);

//去掉裏面的#text文件節點。沒用，這個不是你配置的節點，應該是xml文件隱藏的

if(!cn.getNodeName().equals(“#text”)){

//打印你所配置的所有節點 System.out.println(“node[“+k+”]=”+cn.getNodeName()+” nodeValue[“+k+”]=”+cn.getTextContent());

}

}

}

}

}

}

}

}

}

//具體你要幹嘛自己弄了！

在Java中如何讀取XML字符串的元素值

java讀取xml節點元素，主要使用java提供的解析xml的工具類SAXParserFactory，如下代碼：

package xml.xmlreader;import java.io.File;import java.net.URL;import java.util.Properties;import javax.xml.parsers.SAXParser;import javax.xml.parsers.SAXParserFactory;public class CFGParser {//解析xml文件的工具類 private Properties props; public Properties getProps() { return props; } public void setProps(Properties props) { this.props = props; } public void parse(String filename) throws Exception { CFGHandler handler = new CFGHandler(); SAXParserFactory factory = SAXParserFactory.newInstance(); factory.setNamespaceAware(false); factory.setValidating(false); SAXParser parser = factory.newSAXParser(); URL confURL = super.getClass().getClassLoader().getResource(filename); if (confURL == null) { System.out.println(“Can’t find configration file.”); return; } try { parser.parse(confURL.toString(), handler); this.props = handler.getProps(); } finally { factory = null; parser = null; handler = null; } } public void parseFile(String filename) throws Exception { CFGHandler handler = new CFGHandler(); SAXParserFactory factory = SAXParserFactory.newInstance(); factory.setNamespaceAware(false); factory.setValidating(false); SAXParser parser = factory.newSAXParser(); File f = new File(filename); if ((f == null) || (!f.exists())) return; try { parser.parse(f, handler); this.props = handler.getProps(); } finally { factory = null; parser = null; handler = null; } }}package xml.xmlreader;import java.util.Properties;import org.xml.sax.Attributes;import org.xml.sax.SAXException;import org.xml.sax.helpers.DefaultHandler; public class CFGHandler extends DefaultHandler{ private Properties props; private String currentSet; private String currentName; private StringBuffer currentValue = new StringBuffer(); public CFGHandler() { this.props = new Properties(); } public Properties getProps() { return this.props; } public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException { this.currentValue.delete(0, this.currentValue.length()); this.currentName = qName; } public void characters(char[] ch, int start, int length) throws SAXException { this.currentValue.append(ch, start, length); } public void endElement(String uri, String localName, String qName) throws SAXException { this.props.put(qName.toLowerCase(), this.currentValue.toString().trim()); }}xml文件 ?xml version=”1.0″ encoding=”UTF-8″?xml-body refresh_userlist desc=”用戶列表刷新間隔時間(秒)”6/refresh_userlist refresh_message desc=”短消息刷新間隔時間(秒)”10/refresh_message morningbegin desc=”上午上班時間”23:00/morningbegin morningend desc=”上午下班時間”12:00/morningend afternoonbegin desc=”下午上班時間”18:00/afternoonbegin/xml-bodyjsp獲取各個節點的值：%@ page language=”java” import=”java.util.*” pageEncoding=”UTF-8″%html jsp:useBean id=”cfgp” scope=”page” class=”xml.xmlreader.CFGParser”/jsp:useBean body % cfgp.parse(“kaoqin.xml”); Properties pro = cfgp.getProps(); String stTime = pro.getProperty(“morningbegin”); String edTime = pro.getProperty(“morningend”); String afternoonbegin = pro.getProperty(“afternoonbegin”); out.println(stTime+”\n”+edTime+”\n”+afternoonbegin); System.out.println(stTime+”\n”+edTime+”\n”+afternoonbegin); % /body/html