java解压Apk文件

方法比较简单，只是自己记录下

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Enumeration;
import java.util.LinkedList;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

   public static void decompress(String zipPath, String targetPath) throws IOException  {    
       File file = new File(zipPath);  
       if (!file.isFile()) {  
           throw new FileNotFoundException("file not exist!");  
       }  
       if (targetPath == null || "".equals(targetPath)) {  
           targetPath = file.getParent();  
       }    
       ZipFile zipFile = new ZipFile(file);  
       Enumeration<? extends ZipEntry> files = zipFile.entries();  
       ZipEntry entry = null;  
       File outFile = null;  
       BufferedInputStream bin = null;  
       BufferedOutputStream bout = null;  
       while (files.hasMoreElements()) {  
           entry = files.nextElement();  
           outFile = new File(targetPath + File.separator + entry.getName());  
           // 如果条目为目录，则跳向下一个   
           if(entry.isDirectory()){
               outFile.mkdirs();  
               continue;  
           }  
           // 创建目录  
           if (!outFile.getParentFile().exists()) {  
               outFile.getParentFile().mkdirs();  
           }  
           // 创建新文件  
           outFile.createNewFile();  
           // 如果不可写，则跳向下一个条目  
           if (!outFile.canWrite()) {  
               continue;  
           }  
           try {  
               bin = new BufferedInputStream(zipFile.getInputStream(entry));  
               bout = new BufferedOutputStream(new FileOutputStream(outFile));  
               byte[] buffer = new byte[1024];  
               int readCount = -1;  
               while ((readCount = bin.read(buffer)) != -1) {  
                   bout.write(buffer, 0, readCount);  
               }  
           } finally {  
               try {  
                   bin.close();  
                   bout.flush();  
                   bout.close();  
               } catch (Exception e) {}  
           }  
       }  
   } 

有了上面的代码，我们想要获取apk文件里的某一个文件就便

	public InputStream getInputStream(String filename) throws IOException {
		InputStream is = null;
		
		// check if zip file is already opened
		if(this.zip == null)
			this.zip = new ZipFile(this.apk);//根据给定的apk文件创建对应的zip文件
		
		// search for file with given filename
		Enumeration<?> entries = this.zip.entries();
		while (entries.hasMoreElements()) {
			ZipEntry entry = (ZipEntry) entries.nextElement();
			
			String entryName = entry.getName();
			if (entryName.equals(filename)) {
				is = this.zip.getInputStream(entry);
				break;
			}
		}
		
		return is;
	}