下面小编就为大家带来一篇java读取xml文件的四种方法总结(必看篇)。小编觉得挺不错的，现在就分享给大家，也给大家做个参考。一起跟随小编过来看看吧
java操作xml文档主要有四种方式，分别是dom、sax、jdom和dom4j，dom和sax是官方提供的，而jdom和dom4j则是引用第三方库的，其中用的最多的是dom4j方式。运行效率和内存使用方面最优的是sax，但是由于sax是基于事件的方式，所以sax无法在编写xml的过程中对已编写内容进行修改，但对于不用进行频繁修改的需求，还是应该选择使用sax。
下面基于这四种方式来读取xml文件。
第一，以dom的方式实现。
package xmls;
import org.w3c.dom.document;
import org.w3c.dom.element;
import org.w3c.dom.node;
import org.w3c.dom.nodelist;
import org.xml.sax.saxexception;
import javax.xml.parsers.documentbuilder;
import javax.xml.parsers.documentbuilderfactory;
import javax.xml.parsers.parserconfigurationexception;
import java.io.file;
import java.io.ioexception;
/**
* created by lenovo on 2017-6-3.
*/
public class domreaddemo {
public static void main(string[] args){
documentbuilderfactory dbf = documentbuilderfactory.newinstance();
try{
documentbuilder db = dbf.newdocumentbuilder();
document document = db.parse("src/xmls/dom.xml");
nodelist booklist = document.getelementsbytagname("book");
for(int i = 0; i < booklist.getlength(); i++){
system.out.println("--------第" + (i+1) + "本书----------");
element ele = (element) booklist.item(i);
nodelist childnodes= ele.getchildnodes();
for(int j = 0; j < childnodes.getlength(); j++){
node n = childnodes.item(j);
if(n.getnodename() != "#text"){
system.out.println(n.getnodename() + ":" + n.gettextcontent());
}
}
system.out.println("---------------------------------");
}
}catch (parserconfigurationexception e){
e.printstacktrace();
}catch (ioexception e){
e.printstacktrace();
}catch (saxexception e){
e.printstacktrace();
}
}
}
第二，以sax的方式实现。
package xmls;
import javax.xml.parsers.saxparser;
import javax.xml.parsers.saxparserfactory;
/**
* created by lenovo on 2017-6-1.
*/
public class xmltest2 {
public static void main(string[] args){
saxparserfactory spf = saxparserfactory.newinstance();
try{
saxparser sp = spf.newsaxparser();
saxparserhandler handler = new saxparserhandler();
sp.parse("src\\xmls\\book.xml", handler);
}catch (exception e){
e.printstacktrace();
}
}
}
package xmls;
import org.xml.sax.attributes;
import org.xml.sax.saxexception;
import org.xml.sax.helpers.defaulthandler;
/**
* created by lenovo on 2017-6-1.
*/
public class saxparserhandler extends defaulthandler {
@override
public void startdocument() throws saxexception {
super.startdocument();
system.out.println("sax解析开始");
}
@override
public void enddocument() throws saxexception {
super.enddocument();
system.out.println("sax解析结束");
}
@override
public void startelement(string s, string s1, string s2, attributes attributes) throws saxexception {
super.startelement(s, s1, s2, attributes);
system.out.println(s2);
for(int i = 0; i < attributes.getlength(); i++){
string name = attributes.getqname(i);
string value = attributes.getvalue(name);
system.out.println("属性值：" + name + "=" + value);
}
}
@override
public void endelement(string s, string s1, string s2) throws saxexception {
super.endelement(s, s1, s2);
if(s2.equals("book")){
system.out.println("-----------------------");
}
}
@override
public void characters(char[] ch, int start, int length) throws saxexception {
super.characters(ch, start, length);
string value = new string(ch, start, length);
if(value.trim().equals("")){
return;
}
system.out.println(value);
}
}
第三，以jdom的方式实现。
package xmls;
import org.jdom2.attribute;
import org.jdom2.document;
import org.jdom2.element;
import org.jdom2.jdomexception;
import org.jdom2.input.jdomparseexception;
import org.jdom2.input.saxbuilder;
import java.io.*;
import java.util.list;
/**
* created by lenovo on 2017-6-2.
*/
public class jdomtest {
public static void main(string[] args){
saxbuilder saxbuilder = new saxbuilder();
inputstream in;
try{
in = new fileinputstream(new file("src\\xmls\\book.xml"));
document document = saxbuilder.build(in);
element rootelement = document.getrootelement();
list<element> booklist = rootelement.getchildren();
for(element book: booklist){
system.out.println("第" + (booklist.indexof(book)+1) + "本书！");
list<attribute> attrs = book.getattributes();
for(attribute attr: attrs){
system.out.println(attr.getname() + "=" + attr.getvalue());
}
for(element item: book.getchildren()){
system.out.println(item.getname() + ":" + item.getvalue());
}
system.out.println("------------------------------------");
}
}catch (filenotfoundexception e){
e.printstacktrace();
}catch (jdomexception e){
e.printstacktrace();
}catch (ioexception e){
e.printstacktrace();
}
}
}
第四，以dom4j的方式实现。
package xmls;
import org.dom4j.*;
import org.dom4j.io.outputformat;
import org.dom4j.io.saxreader;
import org.dom4j.io.xmlwriter;
import java.io.file;
import java.io.fileoutputstream;
import java.io.ioexception;
import java.util.iterator;
import java.util.list;
/**
* created by lenovo on 2017-6-2.
*/
public class dom4jtest {
public void parsexml(){
saxreader saxreader = new saxreader();
try{
document document = saxreader.read(new file("src\\xmls\\book.xml"));
element rootelement = document.getrootelement();
iterator it = rootelement.elementiterator();
while (it.hasnext()){
element book = (element)it.next();
list<attribute> attrs = book.attributes();
for(attribute attr: attrs){
system.out.println("属性名：" + attr.getname() + "---- 属性值：" + attr.getvalue() );
}
iterator cit = book.elementiterator();
while (cit.hasnext()){
element child = (element) cit.next();
system.out.println("子节点：" + child.getname());
}
}
}catch (documentexception e){
e.printstacktrace();
}
}
public static void main(string[] args){
dom4jtest dom4jtest = new dom4jtest();
dom4jtest.parsexml();
}
}
以上就是java读取xml文件的四种方法(收藏)的详细内容。