Java文件操作大全（六）

39.写入XML数据库
//import java.io.*;
//import javax.xml.parsers.*;
//import org.xml.sax.*;
//import org.w3c.dom.*;
//import javax.xml.transform.*;
//import javax.xml.transform.dom.*;
//import javax.xml.transform.stream.*;
private Document document;
private Element node;
File xml_file=new File(%%1);
DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance();
try {
DocumentBuilder builder=factory.newDocumentBuilder();
document=builder.parse(xml_file);
} catch(Exception e) {
e.printStackTrace();
}
String subNodeTag=%%2;
Element rootNode=document.getDocumentElement();
//%%2="serverList" //%%4="id" //%%6="port"
//%%3="server" //%%5="ipaddr"
NodeList nlist=rootNode.getElementByTagName(subNodeTag);
node=document.createElement(%%3);
node.setAttribute(%%4,nlist.getLength()+1).toString());
node.appendChild(document.createTextNode("/n");
Element ipNode=document.createElement(%%5);
ipNode.appendChild(document.createTextNode(%%8));
node.appendChild(ipNode);
node.appendChild(document,createTextNode("/n");
Element port=document.createElement(%%6);
port.appendChild(document.createTextNode(%%9));
node.appendChild(port);
node.appendChild(document,createTextNode("/n");
nlist.appendChild(node);
TransformerFactory tFactory=TransformerFactory.newInstance();
Transformer transformer=null;
try {
transformer=tFactory.newTransformer();
DOMSource source=new DOMSource(document);
StreamResult result=new StreamResult(xml_file);
transformer.transform(source,result);
} catch(Exception e) {
e.printStackTrace();
}

40.ZIP压缩文件
//import java.io.*;
//import java.util.zip.*;
//创建文件输入流对象
FileInputStream fis=new FileInputStream(%%1);
//创建文件输出流对象
FileOutputStream fos=new FileOutputStream(%%2);
//创建ZIP数据输出流对象
ZipOutputStream zipOut=new ZipOutputStream(fos);
//创建指向压缩原始文件的入口
ZipEntry entry=new ZipEntry(args[0]);
zipOut.putNextEntry(entry);
//向压缩文件中输出数据
int nNumber;
byte[] buffer=new byte[1024];
while((nNumber=fis.read(buffer))!=-1)
zipOut.write(buffer,0,nNumber);
//关闭创建的流对象
zipOut.close();
fos.close();
fis.close();
}
catch(IOException e)
{
System.out.println(e);
}
41.获得应用程序完整路径
String %%1=System.getProperty("user.dir");

42.ZIP解压缩
//import java.io.*;
//import java.util.zip.*;
try{
//创建文件输入流对象实例
FileInputStream fis=new FileInputStream(%%1);
//创建ZIP压缩格式输入流对象实例
ZipInputStream zipin=new ZipInputStream(fis);
//创建文件输出流对象实例
FileOutputStream fos=new FileOutputStream(%%2);
//获取Entry对象实例
ZipEntry entry=zipin.getNextEntry();
byte[] buffer=new byte[1024];
int nNumber;
while((nNumber=zipin.read(buffer,0,buffer.length))!=-1)
fos.write(buffer,0,nNumber);
//关闭文件流对象
zipin.close();
fos.close();
fis.close();
}
catch(IOException e) {
System.out.println(e);
}

43.递归删除目录中的文件
//import java.io.*;
//import java.util.*;
ArrayList<String> folderList = new ArrayList<String>();
folderList.add(%%1);
for (int j = 0; j < folderList.size(); j++) {
File file = new File(folderList.get(j));
File[] files = file.listFiles();
ArrayList<File> fileList = new ArrayList<File>();
for (int i = 0; i < files.length; i++) {
if (files[i].isDirectory()) {
folderList.add(files[i].getPath());
} else {
fileList.add(files[i]);
}
}
for (File f : fileList) {
f.delete();
}
}

43.ZIP压缩文件夹
//import java.io.*;
//import org.apache.tools.zip.ZipOutputStream; //这个包在ant.jar里，要到官方网下载
//import java.util.zip.*;
try {
String zipFileName = %%2; //打包后文件名字
File f=new File(%%1);
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFileName));
String base= "";
if (f.isDirectory()) {
File[] fl = f.listFiles();
out.putNextEntry(new org.apache.tools.zip.ZipEntry(base + "/"));
base = base.length() == 0 ? "" : base + "/";
for (int i = 0; i < fl.length; i++) {
zip(out, fl[i], base + fl[i].getName());
}
}else {
out.putNextEntry(new org.apache.tools.zip.ZipEntry(base));
FileInputStream in = new FileInputStream(f);
int b;
while ( (b = in.read()) != -1) {
out.write(b);
}
in.close();
}
out.close();
}catch (Exception ex) {
ex.printStackTrace();
}
44.Java验证DTD
//import java.io.*;
//import javax.xml.parsers.*;
//import org.xml.sax.*;
//import org.w3c.dom.*;
try {
InputStream in=new FileInputStream(filePath);
SAXReader saxReader = new SAXReader();
this.document = saxReader.read(in);
DocumentBuilderFactory factory = null;
factory = DocumentBuilderFactory.newInstance();
//进行dtd检查
factory.setValidating(true);
} catch (Exception e) {
}