java实现xml文件CRUD

大家好，又见面了，我是全栈君，今天给大家准备了Idea注册码。

java删除xml多个节点:

方案1、你直接改动了nodeList。这一般在做循环时是不同意直接这么做的。
你能够尝试在遍历一个list时，在循环体同一时候删除list里的内容，你会得到一个异常。建议你例如以下处理这个问题：            XmlDocument xmlDoc = new XmlDocument();            xmlDoc.Load("11.xml");            XmlNode root = xmlDoc.DocumentElement;            XmlNodeList nodeList = root.ChildNodes;            List<XmlNode> nodesToRemove = new List<XmlNode>();            foreach (XmlNode node in nodeList)            {                if (node.Attributes["FileName"] == null || node.Attributes["FileName"].Value == "")                {                    nodesToRemove.Add(node);                    continue;                }                //省略此处代码dosomething            }            foreach (XmlNode node in nodesToRemove)//这里再来做删除            {                node.ParentNode.RemoveChild(node);            }

方案2、

 nodelist = xmldoc.SelectSingleNode("employees").ChildNodes;

while (true) 2 { 3     bool removed = false; 4     foreach (XmlNode xn in nodelist) 5    { 6         if (xn.FirstChild.InnerText.ToString().Contains("a")) 7        { 8            xn.ParentNode.RemoveChild(xn); 9            removed = true;10            break;11         }12     }13 14     if (!removed)15          break;16 }

package com.wss;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
public class GPS_GNSS_XML_Color {
//删除节点时传入的參数
private static String deleteNumber;
//改动节点时传入的參数
private static String updateNumber;
//读取传入的路径，返回一个document对象
public static Document loadInit(String filePath){
Document document = null;
try{
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
document = builder.parse(new File(filePath));
document.normalize();
return document;
}catch(Exception e){
e.printStackTrace();
System.out.println(e.getMessage());
return null;
}
}

public static boolean deleteXML(String filePath){
deleteNumber = “421f481e-790c-41be-91e3-27d215b73ce2”;
Document document = loadInit(filePath);
try{
NodeList nodeList = document.getElementsByTagName_r(“color”);
for(int i=0; i<nodeList.getLength(); i++){
String number_ = document.getElementsByTagName_r(“number”).item(i).getFirstChild().getNodeValue();
//删除节点时传入的參数
if(number_.equals(deleteNumber)){
Node node = nodeList.item(i);
node.getParentNode().removeChild(node);
saveXML(document, filePath);
}
}
return true;
}catch(Exception e){
e.printStackTrace();
System.out.println(e.getMessage());
return false;
}
}

public static boolean updateXML(String filePath){
updateNumber = “421f481e-790c-41be-91e3-27d215b73ce2”;
//读取传入的路径，返回一个document对象
Document document = loadInit(filePath);
try{
//获取叶节点
NodeList nodeList = document.getElementsByTagName_r(“color”);
//遍历叶节点
for(int i=0; i<nodeList.getLength(); i++){
String number = document.getElementsByTagName_r(“number”).item(i).getFirstChild().getNodeValue();
String colorValue = document.getElementsByTagName_r(“colorValue”).item(i).getFirstChild().getNodeValue();
Double minValue = Double.parseDouble(document.getElementsByTagName_r(“minValue”).item(i).getFirstChild().getNodeValue());
Double maxValue =Double.parseDouble(document.getElementsByTagName_r(“maxValue”).item(i).getFirstChild().getNodeValue());
//改动节点时传入的參数
if(number.equals(updateNumber)){
document.getElementsByTagName_r(“colorValue”).item(i).getFirstChild().setNodeValue(“black”);
document.getElementsByTagName_r(“minValue”).item(i).getFirstChild().setNodeValue(“2222”);
document.getElementsByTagName_r(“maxValue”).item(i).getFirstChild().setNodeValue(“22222”);
System.out.println();
}
}
saveXML(document, filePath);
return true;
}catch(Exception e){
e.printStackTrace();
System.out.println(e.getMessage());
return false;
}
}

public static boolean addXML(String filePath){
try{
//读取传入的路径。返回一个document对象
Document document = loadInit(filePath);
//创建叶节点
Element eltColor = document.createElement_x(“color”);
Element eltNumber = document.createElement_x(“number”);//创建叶节点的第一个元素
Element eltColorValue = document.createElement_x(“colorValue”);//创建叶节点的第二个元素
Element eltMinValue = document.createElement_x(“minValue”);//创建叶节点的第三个元素
Element eltMaxValue = document.createElement_x(“maxValue”);//创建叶节点的第四个元素
Text number_ = document.createTextNode(UUID.randomUUID().toString());//创建叶节点的第一个元素下的文本节点
eltNumber.appendChild(number_);//把该文本节点增加到叶节点的第一个元素里面
Text colorValue_ = document.createTextNode(“colorValue”);//创建叶节点的第二个元素下的文本节点
eltColorValue.appendChild(colorValue_);//把该文本节点增加到叶节点的第二个元素里面
Text minValue_ = document.createTextNode(“100”);//创建叶节点的第三个元素下的文本节点
eltMinValue.appendChild(minValue_);//把该文本节点增加到叶节点的第三个元素里面
Text maxValue_ = document.createTextNode(“200”);//创建叶节点的第四个元素下的文本节点
eltMaxValue.appendChild(maxValue_);//把该文本节点增加到叶节点的第四个元素里面
//把叶节点下的元素增加到叶节点下
eltColor.appendChild(eltNumber);
eltColor.appendChild(eltColorValue);
eltColor.appendChild(eltMinValue);
eltColor.appendChild(eltMaxValue);
//获取根节点
Element eltRoot = document.getDocumentElement();
//把叶节点增加到根节点下
eltRoot.appendChild(eltColor);
//更新改动后的源文件
saveXML(document, filePath);
return true;
}catch(Exception e){
e.printStackTrace();
System.out.println(e.getMessage());
return false;
}
}

public static boolean saveXML(Document document, String filePath){
try{
TransformerFactory tFactory = TransformerFactory.newInstance();
Transformer transformer = tFactory.newTransformer();
DOMSource source = new DOMSource(document);
StreamResult result = new StreamResult(new File(filePath));
transformer.transform(source, result);
return true;
}catch(Exception e){
e.printStackTrace();
System.out.println(e.getMessage());
return false;
}
}

public static List<ColorValue> selectXML(String filePath){
List<ColorValue> colorValueList = new ArrayList<ColorValue>();
try{
//读取传入的路径，返回一个document对象
Document document = loadInit(filePath);
//获取叶节点
NodeList nodeList = document.getElementsByTagName_r(“color”);
//遍历叶节点
for(int i=0; i<nodeList.getLength(); i++){
ColorValue colorValue = new ColorValue();
String number_ = document.getElementsByTagName_r(“number”).item(i).getFirstChild().getNodeValue();
String colorValue_ = document.getElementsByTagName_r(“colorValue”).item(i).getFirstChild().getNodeValue();
Double minValue_ = Double.parseDouble(document.getElementsByTagName_r(“minValue”).item(i).getFirstChild().getNodeValue());
Double maxValue_ = Double.parseDouble(document.getElementsByTagName_r(“maxValue”).item(i).getFirstChild().getNodeValue());
colorValue.setNumber(number_);
colorValue.setColorValue(colorValue_);
colorValue.setMinValue(minValue_);
colorValue.setMaxValue(maxValue_);
colorValueList.add(colorValue);
}
return colorValueList;
}catch(Exception e){
e.printStackTrace();
System.out.println(e.getMessage());
return null;
}
}
}

package com.wss;
public class ColorValue {
private String number;
private String colorValue;
private Double minValue;
private Double maxValue;
public String getNumber() {
return number;
}
public void setNumber(String number) {
this.number = number;
}
public String getColorValue() {
return colorValue;
}
public void setColorValue(String colorValue) {
this.colorValue = colorValue;
}
public Double getMinValue() {
return minValue;
}
public void setMinValue(Double minValue) {
this.minValue = minValue;
}
public Double getMaxValue() {
return maxValue;
}
public void setMaxValue(Double maxValue) {
this.maxValue = maxValue;
}
}

xml version=”1.0″ encoding=”UTF-8″ standalone=”no”?

>
<Colors>
<color>
<number>7007b384-fab3-4779-9171-229d0664b6b5</number>
<colorValue>black</colorValue>
<minValue>2222</minValue>
<maxValue>22222</maxValue>
</color>
<color>
<number>421f481e-790c-41be-91e3-27d215b73ce2</number>
<colorValue>colorValue</colorValue>
<minValue>100</minValue>
<maxValue>200</maxValue>
</color>
</Colors>

xml的初始化及增删改查操作：

//初始化

   private void btnInitActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnInitActionPerformed

       // TODO add your handling code here:

       try {

           File file = new File(“books.xml”);

           DocumentBuilderFactory docFactory = DocumentBuilderFactory.

                                               newInstance();

           DocumentBuilder builder = docFactory.newDocumentBuilder();

           if (!file.exists()) {

               doc = builder.newDocument();

               Element books = doc.createElement(“books”);

               doc.appendChild(books);

           } else {

               doc = builder.parse(file);

           }

           this.jTextArea1.setText(“初始化完毕”);

       } catch (Exception ex) {

           this.jTextArea1.setText(“初始化失败”);

       }

   }//GEN-LAST:event_btnInitActionPerformed

   private void btnSaveActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnSaveActionPerformed

       // TODO add your handling code here:

       try {

           TransformerFactory tfactory = TransformerFactory.newInstance();

           Transformer transformer = tfactory.newTransformer();

           transformer.setOutputProperty(OutputKeys.INDENT, “yes”);

           DOMSource source = new DOMSource(doc);

           StreamResult result = new StreamResult(new File(“books.xml”));

           transformer.transform(source, result);

           this.jTextArea1.setText(“保存成功”);

       } catch (Exception ex) {

           this.jTextArea1.setText(“保存失败”);

       }

   }//GEN-LAST:event_btnSaveActionPerformed

   private void btnShowActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnShowActionPerformed

       // TODO add your handling code here:

       if (doc != null) {

           Element books = doc.getDocumentElement();

           this.jTextArea1.setText(books.getNodeName());

           NodeList nl = null;

           nl = books.getChildNodes();

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

               Node node = nl.item(i);

               //节点类型,元素1/属性2/文本3/凝视8/文档9

               if (node.getNodeType() == 1) {

                   this.jTextArea1.append(“\n\t” + node.getNodeName());

                   NodeList nsubs = node.getChildNodes();

                   for (int j = 0; j < nsubs.getLength(); j++) {

                       if (nsubs.item(j).getNodeType() == 1 &&

                           nsubs.item(j).getFirstChild() != null) {

                           this.jTextArea1.append(“\n\t\t” +

                                   nsubs.item(j).getNodeName() + ” : ” +

                                   nsubs.item(j).getFirstChild().

                                   getNodeValue());

                       }

                   }

               }

           }

       }

   }//GEN-LAST:event_btnShowActionPerformed

   private void btnShow2ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnShow2ActionPerformed

       // TODO add your handling code here:

       String msg = “”;

       if (doc != null){

           NodeList nl = doc.getElementsByTagName(“*”);



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

               Element e = (Element)nl.item(i);

               //得到属性

               NamedNodeMap nnm = e.getAttributes();

               msg += “元素：” + e.getNodeName() +”:” + e.getFirstChild().getNodeValue() + “\n”;

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

                   Attr att = (Attr)nnm.item(k);

                   msg += “\t属性有\t”+ att.getNodeName() + “:” + att.getNodeValue()+”\n”;

               }

           }

       }

       this.jTextArea1.setText(msg);

   }//GEN-LAST:event_btnShow2ActionPerformed

   private void btnSearchActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnSearchActionPerformed

       // TODO add your handling code here:

       Node node = Search(this.jTextField1.getText());

       if (node != null) {

           this.jTextArea1.setText(“找到了此元素”);

           this.jTextArea1.append(“\n\t书籍编号 \t: ” + this.jTextField1.getText());

           NodeList list = node.getChildNodes();

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

               Node sub = list.item(i);

               if (sub.getNodeType() == 1 && sub.getFirstChild() != null) {

                   this.jTextArea1.append(“\n\t” + sub.getNodeName() + ” \t: ” +

                                          sub.getFirstChild().getNodeValue());

               }

           }

       }

       else {

           this.jTextArea1.setText(“找不到此元素”);

       }

   }//GEN-LAST:event_btnSearchActionPerformed

   private void btnAddActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnAddActionPerformed

       // TODO add your handling code here:

       try {

           //创建元素

           Element elemBook = doc.createElement(“book”);

           //加入到根元素底下

           doc.getDocumentElement().appendChild(elemBook);

           //为book元素设置属性

           Attr attrId = doc.createAttribute(“id”); //创建

           attrId.setNodeValue(this.jTextField1.getText()); //设置值

           elemBook.setAttributeNode(attrId); //设置到book元素

           //为book元素加入子元素name

           Element elemNode = doc.createElement(“name”); //创建

           Text textNode = doc.createTextNode(this.jTextField2.getText()); //创建文本节点

           elemNode.appendChild(textNode); //为name子元素指定文本

           elemBook.appendChild(elemNode); //加入为book的子元素

           //为book元素加入子元素price

           elemNode = doc.createElement(“price”); //创建

           textNode = doc.createTextNode(this.jTextField3.getText()); //创建文本节点

           elemNode.appendChild(textNode); //为price子元素指定文本

           elemBook.appendChild(elemNode); //加入为book的子元素

           //为book元素加入子元素pub

           elemNode = doc.createElement(“pub”); //创建

           textNode = doc.createTextNode(this.jTextField4.getText()); //创建文本节点

           elemNode.appendChild(textNode); //为pub子元素指定文本

           elemBook.appendChild(elemNode); //加入为book的子元素

           //为book元素加入子元素author

           elemNode = doc.createElement(“author”); //创建

           textNode = doc.createTextNode(this.jTextField5.getText()); //创建文本节点

           elemNode.appendChild(textNode); //为author子元素指定文本

           elemBook.appendChild(elemNode);

           this.jTextArea1.setText(“加入成功”);

       } catch (Exception ex) {

           this.jTextArea1.setText(“加入失败”);

       }

   }//GEN-LAST:event_btnAddActionPerformed

   private void btnModifyActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnModifyActionPerformed

       // TODO add your handling code here:

       Node node = Search(this.jTextField1.getText());

       String[] values = {this.jTextField2.getText(), this.jTextField3.getText(),

                         this.jTextField4.getText(), this.jTextField5.getText()};

       if (node != null) {

           NodeList nl = node.getChildNodes();

           int k = 0;

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

               Node n = nl.item(i);

               if (n.getNodeType() == 1) {

                   Node newNode = doc.createTextNode(values[k]);

                   if (n.getFirstChild() != null) {

                       n.replaceChild(newNode, n.getFirstChild());

                   } else {

                       n.appendChild(newNode);

                   }

                   k = k + 1;

               }

           }

           this.jTextArea1.setText(“改动成功”);

       } else {

           this.jTextArea1.setText(“找不到要改动的节点”);

       }

   }//GEN-LAST:event_btnModifyActionPerformed

   private void btnDelActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnDelActionPerformed

       // TODO add your handling code here:

       Node node = Search(this.jTextField1.getText());

       if (node != null) {

           Node parent = node.getParentNode();

           parent.removeChild(node);

           this.jTextArea1.setText(“删除成功”);

       } else {

           this.jTextArea1.setText(“找不到要删除的节点”);

       }

   }//GEN-LAST:event_btnDelActionPerformed

   private Node Search(String id) {

       Node node = null;

       Element books = doc.getDocumentElement();

       NodeList nl = null;

       if (books.hasChildNodes()) {

           nl = books.getChildNodes();

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

               node = nl.item(i);

               if (node.getNodeType() == 1) {

                   Element ele = (Element) node;

                   if (ele.getAttribute(“id”).equals(id)) {

                       return node;

                   }

               }

           }

       }

       return null;

   }