dom4j是一個(gè)Java的XML API机错,是jdom的升級品,用來讀寫XML文件的父腕。dom4j是一個(gè)十分優(yōu)秀的javaXML API弱匪,具有性能優(yōu)異、功能強(qiáng)大和極其易使用的特點(diǎn)璧亮,它的性能超過sun公司官方的dom技術(shù)萧诫,同時(shí)它也是一個(gè)開放源代碼的軟件,可以在SourceForge上找到它枝嘶。
一帘饶、dom4j介紹
使用方式:在pom.xml中導(dǎo)入dom4j對應(yīng)的jar
<dependency>
<groupId>dom4j</groupId>
<artifactId>dom4j</artifactId>
<version>1.6.1</version>
</dependency>
優(yōu)點(diǎn):dom4j使Java生成和解析XML靈活性變高,并且代碼易于維護(hù)群扶。
API操作類:
Document:表示xml文檔信息及刻,是一個(gè)樹形結(jié)構(gòu)
Eelment:表示xml的元素結(jié)點(diǎn),提供一些操作其子元素方法的竞阐,如文本缴饭、屬性、名稱空間等
Attribute:表示元素結(jié)點(diǎn)中的屬性
二骆莹、常用API
1.創(chuàng)建Document 和Element對象:
Document doc=DocumentHelper.createDocument();
Element eltRoot=DocumentHelper.createElement("student");
doc.setRootElement(eltRoot);
2.或者先準(zhǔn)備好根元素颗搂,使用有參數(shù)的構(gòu)造方法創(chuàng)建Document對象。
Element eltRoot=DocumentHelper.createElement(“student”);
Document doc=DocumentHelper.createDocument(eltRoot);
3.添加節(jié)點(diǎn)和設(shè)置節(jié)點(diǎn)內(nèi)容
Element eltName=eltRoot.addElement(“name”);
Element eltAge=eltRoot.addElement(“age”);
eltName.setText(“張三”);
eltAge.setText(“18”);
4.添加屬性
eltRoot.addAttribute(“sn”,”01”);
5.使用 SAXReader 構(gòu)建dom4j文檔對象
SAXReader saxReader=new SAXReader();
File file=new File(“student.xml”);
Document doc=saxReader.read(file);
6.使用DOMReader 構(gòu)建dom4j 文檔對象
DocumentBuilderFactory dbf=new DocumentBuilderFactory.newInstance();
DocumentBuilder db=dbf.newDocumentBuilder();
File file=new File(“student.xml”);
org.w3c.dom.Document document=db.parse(file);
DOMReader domReader=new DOMReader();
org.dom4j.Document doc=domReader.read(document);
7.訪問根節(jié)點(diǎn):
Element root=doc.getRootElement();
8.訪問所有節(jié)點(diǎn):
java.util.List childrenList=elt.elements();
9.訪問指定名稱的所有節(jié)點(diǎn)
java.util.Liat childrenList=elt.elements(“student”);
10.訪問指定名稱第一個(gè)節(jié)點(diǎn)
Element eltChild=elt.element(“student”);
11.要迭代某個(gè)元素的所有子元素
for(java.util.Iterator it=root.elementIterator();it.hasNext()){
Element element =it.hasNext();
……
}
輸出文檔:
對象:XMLWriter 實(shí)例方法:write(Document doc)
常用的幾種構(gòu)造方法總結(jié):
1:無參數(shù):
2:字節(jié)流參數(shù)
3:字符流參數(shù)幕垦。
4:文檔輸出格式類參數(shù)丢氢。
示例代碼1:
輸出文檔內(nèi)容到控制臺
XMLWriter xw=new XMLWriter();
xw.write(doc);
三、dom4j 生成 xml
實(shí)現(xiàn)步驟:
第一步:創(chuàng)建一個(gè)Document實(shí)例
Document doc = DocumentHelper.createDocument();
第二步:先添加一個(gè)根結(jié)點(diǎn)先改,然后再添加子結(jié)點(diǎn)疚察,構(gòu)造成一個(gè)樹形結(jié)構(gòu)
Element root = doc.addElement("root");
第三步:添加xml文件樣式(也可自定義樣式),并輸出xml文件到指定的路徑下
OutputFormat format = OutputFormat.createPrettyPrint();
XMLWriter writer = new XMLWriter(new FileOutputStream(file), format);
writer.write(doc);
實(shí)現(xiàn)源碼
package com.oysept.xml;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import org.dom4j.Document;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;
import org.jdom2.output.Format;
/**
* dom4j生成xml
* @author ouyangjun
*/
public class CreateDom4j {
public static void main(String[] args) {
// 執(zhí)行dom4j生成xml方法
createDom4j(new File("E:\\dom4j.xml"));
}
public static void createDom4j(File file) {
try {
// 創(chuàng)建一個(gè)Document實(shí)例
Document doc = DocumentHelper.createDocument();
// 添加根節(jié)點(diǎn)
Element root = doc.addElement("root");
// 在根節(jié)點(diǎn)下添加第一個(gè)子節(jié)點(diǎn)
Element oneChildElement= root.addElement("person").addAttribute("attr", "root noe");
oneChildElement.addElement("people").addAttribute("attr", "child one").addText("person one child one");
oneChildElement.addElement("people") .addAttribute("attr", "child two") .addText("person one child two");
// 在根節(jié)點(diǎn)下添加第一個(gè)子節(jié)點(diǎn)
Element twoChildElement= root.addElement("person").addAttribute("attr", "root two");
twoChildElement.addElement("people") .addAttribute("attr", "child one").addText("person two child one");
twoChildElement.addElement("people") .addAttribute("attr", "child two").addText("person two child two");
// xml格式化樣式
// OutputFormat format = OutputFormat.createPrettyPrint(); // 默認(rèn)樣式
// 自定義xml樣式
OutputFormat format = new OutputFormat();
format.setIndentSize(2); // 行縮進(jìn)
format.setNewlines(true); // 一個(gè)結(jié)點(diǎn)為一行
format.setTrimText(true); // 去重空格
format.setPadText(true);
format.setNewLineAfterDeclaration(false); // 放置xml文件中第二行為空白行
// 輸出xml文件
XMLWriter writer = new XMLWriter(new FileOutputStream(file), format);
writer.write(doc);
System.out.println("dom4j CreateDom4j success!");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
XML文件效果圖:
四盏道、dom4j解析xml
實(shí)現(xiàn)步驟
第一步:創(chuàng)建一個(gè)SAXReader解析器
SAXReader reader = new SAXReader();
第二步:解析xml文件稍浆,重新構(gòu)建成一個(gè)Document對象
Document doc = reader.read(file);
第三步:處理Document對象信息,在控制臺打印
實(shí)現(xiàn)源碼:
package com.oysept.xml;
import java.io.File;
import java.util.Iterator;
import java.util.List;
import org.dom4j.Attribute;
import org.dom4j.CDATA;
import org.dom4j.Comment;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.Node;
import org.dom4j.Text;
import org.dom4j.io.SAXReader;
/**
* dom4j解析xml
* @author ouyangjun
*/
public class ParseDom4j {
public static void main(String[] args) {
// 執(zhí)行dom4j解析xml方法
parseDom4j(new File("E:\\dom4j.xml"));
}
public static void parseDom4j(File file) {
try {
// 創(chuàng)建一個(gè)SAXReader解析器
SAXReader reader = new SAXReader();
// 讀取xml文件,轉(zhuǎn)換成Document結(jié)點(diǎn)
Document doc = reader.read(file);
// 遞歸打印xml文檔信息
StringBuffer buffer = new StringBuffer();
parseElement(doc.getRootElement(), buffer);
System.out.println(buffer.toString());
} catch (DocumentException e) {
e.printStackTrace();
}
}
@SuppressWarnings("unchecked")
public static void parseElement(Element element, StringBuffer buffer) {
buffer.append("<"+element.getName());
List<Attribute> attrs = element.attributes();
if (attrs != null) {
for (Attribute attr : attrs) {
buffer.append(" "+attr.getName()+"=\""+attr.getValue()+"\"");
}
}
buffer.append(">");
Iterator<Node> iterator = element.nodeIterator();
while (iterator.hasNext()) {
Node node = iterator.next();
if (node instanceof Element) {
Element eleNode = (Element) node;
parseElement(eleNode, buffer);
}
if (node instanceof Text) {
Text text = (Text) node;
buffer.append(text.getText());
}
if (node instanceof CDATA) {
CDATA dataNode = (CDATA) node;
buffer.append(dataNode.getText());
}
if (node instanceof Comment) {
Comment comNode = (Comment) node;
buffer.append(comNode.getText());
}
}
buffer.append("</"+element.getName()+">");
}
}
XML文件解析效果圖打印:
五衅枫、dom4j解析生成字符串
import java.io.IOException;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;
/**
*
* @author y
*/
public class Test {
/**
* @param args the command line arguments
*/
public static void main(String[] args) throws DocumentException {
Map<String, Object> map = new HashMap<String, Object>();
map.put("name", "李四");
map.put("age", 25);
//System.out.println(map2xml(map));
List<Object> list = new ArrayList<Object>();
list.add("測試1");
list.add("測試2");
list.add("測試3");
//System.out.println(list2xml(list,"items"));
List<Map<String,Object>> listMap = new ArrayList<Map<String,Object>>();
Map<String,Object> map1 = new HashMap<String,Object>();
map1.put("name", "張三");
map1.put("age", 23);
listMap.add(map1);
map1 = new HashMap<String,Object>();
map1.put("name", "李四");
map1.put("age", 24);
listMap.add(map1);
map1 = new HashMap<String,Object>();
map1.put("name", "王五");
map1.put("age", 25);
listMap.add(map1);
System.out.println(listMap2xml(listMap,"users","user"));
}
public static String listMap2xml(List<Map<String,Object>> list,String listRoot,String mapRoot){
Document doc = DocumentHelper.createDocument();
Element rootEle = doc.addElement("result");
Element noEle = rootEle.addElement("no");
Element msgEle = rootEle.addElement("msg");
if(null!=list && !list.isEmpty()){
noEle.setText("1");
msgEle.setText("成功獲取相關(guān)信息");
Element listRootEle = rootEle.addElement(listRoot);
for(Map<String,Object> map:list){
Element mapRootELe = listRootEle.addElement(mapRoot);
Set<Map.Entry<String,Object>> set = map.entrySet();
Iterator<Map.Entry<String,Object>> iter = set.iterator();
while(iter.hasNext()){
Map.Entry<String,Object> entry = (Map.Entry<String,Object>)iter.next();
Element ele = mapRootELe.addElement(entry.getKey());
ele.setText(String.valueOf(entry.getValue()));
}
}
}else{
noEle.setText("0");
msgEle.setText("沒有獲取到相關(guān)信息");
}
StringWriter sw = new StringWriter();
OutputFormat format = OutputFormat.createPrettyPrint();
format.setEncoding("utf-8");
try {
XMLWriter xmlWriter = new XMLWriter(sw, format);
xmlWriter.write(doc);
} catch (IOException ex) {
Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
}finally{
try {
sw.close();
} catch (IOException ex) {
Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
}
}
return sw.toString();
}
public static String list2xml(List<Object> list,String itemRoot){
Document doc = DocumentHelper.createDocument();
Element rootEle = doc.addElement("result");
Element noEle = rootEle.addElement("no");
Element msgEle = rootEle.addElement("msg");
if(null!=list && !list.isEmpty()){
noEle.setText("1");
msgEle.setText("成功獲取相關(guān)信息");
Element itemRootEle = rootEle.addElement(itemRoot);
for(Object obj:list){
Element ele = itemRootEle.addElement("item");
ele.setText(String.valueOf(obj));
}
}else{
noEle.setText("0");
msgEle.setText("沒有獲取到相關(guān)信息");
}
StringWriter sw = new StringWriter();
OutputFormat format = OutputFormat.createPrettyPrint();
format.setEncoding("utf-8");
try {
XMLWriter xmlWriter = new XMLWriter(sw, format);
xmlWriter.write(doc);
} catch (IOException ex) {
Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
}finally{
try {
sw.close();
} catch (IOException ex) {
Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
}
}
return sw.toString();
}
public static String map2xml(Map<String, Object> map) {
Document doc = DocumentHelper.createDocument();
Element rootEle = doc.addElement("result");
Element noEle = rootEle.addElement("no");
Element msgEle = rootEle.addElement("msg");
if(null!=map && !map.isEmpty()){
noEle.setText("1");
msgEle.setText("成功獲取相關(guān)信息");
Set<Map.Entry<String, Object>> set = map.entrySet();
Iterator<Map.Entry<String, Object>> iter = set.iterator();
while(iter.hasNext()){
Map.Entry<String, Object> entry = (Map.Entry<String, Object>) iter.next();
Element ele = rootEle.addElement(entry.getKey());
ele.setText(String.valueOf(entry.getValue()));
}
}else{
noEle.setText("0");
msgEle.setText("沒有獲取到相關(guān)信息");
}
StringWriter sw = new StringWriter();
OutputFormat format = OutputFormat.createPrettyPrint();
format.setEncoding("utf-8");
try {
XMLWriter xmlWriter = new XMLWriter(sw, format);
xmlWriter.write(doc);
} catch (IOException ex) {
Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
}finally{
try {
sw.close();
} catch (IOException ex) {
Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
}
}
return sw.toString();
}
public static void test4() {
Document doc = DocumentHelper.createDocument();
Element rootEle = doc.addElement("sudent");
Element nameEle = rootEle.addElement("name");
nameEle.setText("張三");
Element ageEle = rootEle.addElement("age");
ageEle.setText("25");
try {
StringWriter sw = new StringWriter();
OutputFormat format = OutputFormat.createPrettyPrint();
format.setEncoding("utf-8");
XMLWriter xmlWriter = new XMLWriter(sw, format);
xmlWriter.write(doc);
System.out.println(sw.toString());
} catch (IOException ex) {
Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
}
}
public static void test3() throws DocumentException {
String str = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
+ "<books>"
+ " <book>"
+ " <name>Think in Java</name>"
+ " <price>120.0</price>"
+ " <chapters>"
+ " <c>001</c>"
+ " <c>002</c>"
+ " <c>003</c>"
+ " </chapters>"
+ " </book>"
+ " <book>"
+ " <name>Think in Java2</name>"
+ " <price>220.0</price>"
+ " </book>"
+ "</books>";
Document doc = DocumentHelper.parseText(str);
Element books = doc.getRootElement();
List<Element> childEles = books.elements();
Iterator<Element> iter = childEles.iterator();
while (iter.hasNext()) {
Element book = iter.next();
Element name = book.element("name");
Element price = book.element("price");
System.out.println("name:" + name.getText() + ",price:" + price.getText());
Element chapters = book.element("chapters");
if (null != chapters) {
Iterator<Element> chaptersIter = chapters.elementIterator();
if (null != chaptersIter) {
while (chaptersIter.hasNext()) {
Element c = chaptersIter.next();
System.out.println("===>" + c.getText());
}
}
}
}
}
public static void test2() throws DocumentException {
String str = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
+ "<books>"
+ " <book>"
+ " <name>Think in Java</name>"
+ " <price>120.0</price>"
+ " </book>"
+ " <book>"
+ " <name>Think in Java2</name>"
+ " <price>220.0</price>"
+ " </book>"
+ "</books>";
Document doc = DocumentHelper.parseText(str);
Element books = doc.getRootElement();
List<Element> childEles = books.elements();
Iterator<Element> iter = childEles.iterator();
while (iter.hasNext()) {
Element book = iter.next();
Element name = book.element("name");
Element price = book.element("price");
System.out.println("name:" + name.getText() + ",price:" + price.getText());
}
}
public static void test1() throws DocumentException {
String str = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
+ "<dzswdjz>"
+ " <qr_code>"
+ " <nsrsbh>nsrsbh</nsrsbh >"
+ " <retStatus >retStatus</retStatus>"
+ " <img_name>img_name</img_name>"
+ " <img_byteString>img_byteString</img_byteString>"
+ " </qr_code>"
+ "</dzswdjz>";
Document doc = DocumentHelper.parseText(str);
//獲取到父節(jié)點(diǎn)
Element dzswdjz = doc.getRootElement();
//定位到qr_code節(jié)點(diǎn)
Element qr_code = dzswdjz.element("qr_code");
Element nsrsbh = qr_code.element("nsrsbh");
Element retStatus = qr_code.element("retStatus");
Element img_name = qr_code.element("img_name");
Element img_byteString = qr_code.element("img_byteString");
System.out.println("nsrsbh:" + nsrsbh.getText());
System.out.println("retStatus:" + retStatus.getText());
System.out.println("img_name:" + img_name.getText());
System.out.println("img_byteString:" + img_byteString.getText());
}
}