Sun 自带的Gzip压缩解压xml实例

import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import org.apache.commons.io.IOUtils;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class TestXml {

/**
   * 压缩
   */
  public static String zipXml(String str) throws IOException {
if (str == null || str.length() == 0) {
return str;
}
BASE64Encoder base64encoder = new BASE64Encoder();
ByteArrayOutputStream out = new ByteArrayOutputStream();
GZIPOutputStream gzip = new GZIPOutputStream(out);
gzip.write(str.getBytes("UTF-8"));
gzip.close();
return base64encoder.encode(out.toByteArray());
}
 
  /**
   * 解压
   */
public static String unZipXml(String str) throws IOException {
if (str == null || str.length() == 0) {
return str;
}
BASE64Decoder base64decoder = new BASE64Decoder();
ByteArrayOutputStream out = new ByteArrayOutputStream();
byte[] bytes = base64decoder.decodeBuffer(str);
ByteArrayInputStream in = new ByteArrayInputStream(bytes);
GZIPInputStream gunzip = new GZIPInputStream(in);
byte[] buffer = new byte[256];
int n;
while ((n = gunzip.read(buffer)) >= 0) {
out.write(buffer, 0, n);
}
return out.toString("UTF-8");
}

public static void main(String[] args) throws IOException {
InputStream is = null;
try {
File file = new File("E:hz.xml");
is = (InputStream )new FileInputStream(new File("E:hz.xml"));
} catch (FileNotFoundException e) {
e.printStackTrace();
}

// Byte[] bt = null;
// BufferedInputStream input = new BufferedInputStream(is);// 输入流,用于接收请求的数据
// ByteArrayOutputStream byteOutput = new ByteArrayOutputStream(2048);// 请求数据存放对象，使用了参数2048
//
// byte[] bufferRead = new byte[1024];// 数据缓冲区
// int count = 0;// 每个缓冲区的实际数据长度
//
// while ((count = input.read(bufferRead)) != -1) {
// byteOutput.write(bufferRead, 0, count);
// }
List ioList =  IOUtils.readLines(is);
StringBuilder sb = new StringBuilder(1024);
for(int  i =0; i < ioList.size() ; i++){
sb.append(ioList.get(i));
}
String inStr = sb.toString();
System.out.println("原长度：" + inStr.length());
String outStr = zipXml(inStr);
System.out.println("长度：" + outStr.length());
System.out.println((double)inStr.length()/outStr.length());
System.out.println("压缩比：" + (double)(int)(((double)inStr.length()/outStr.length() + 0.005) * 100) / 100 + " : 1");
System.out.println("压缩后内容：" + outStr);
// String unStr = unZipXml(outStr);
// System.out.println("长度：" + unStr.length());
// System.out.println("解压后内容：" + unStr);
}

}