Android复制Assets中大于1M的Zip压缩包，并解压到SD卡中

package com.demo.asset;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;

import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;

public class MainActivity extends Activity {
    /** Called when the activity is first created. */

    private String ASSETS_NAME = "SETTING.zip";
    private String DB_PATH = Environment.getExternalStorageDirectory() + "/word/rar/";
    private String DB_TOPATH = Environment.getExternalStorageDirectory() + "/word/db/";
    private String DB_NAME = "SETTING.zip";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        //拷贝文件
        try {
            copyDataBase();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
        //解压文件
        String path= DB_PATH + DB_NAME;
        File zipFile= new File(path);
        try {
            upZipFile(zipFile, DB_TOPATH);
        } catch (ZipException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
    }

    private void copyDataBase() throws IOException {
        // Path to the just created empty db
        String outFileName = DB_PATH + DB_NAME;
        // 判断目录是否存在。如不存在则创建一个目录
        File file = new File(DB_PATH);
        if (!file.exists()) {
            file.mkdirs();
        }
        file = new File(outFileName);
        if (!file.exists()) {
            file.createNewFile();
        }
        // Open your local db as the input stream
        InputStream myInput = this.getAssets().open(ASSETS_NAME);
        // Open the empty db as the output stream128
        OutputStream myOutput = new FileOutputStream(outFileName);
        // transfer bytes from the inputfile to the outputfile130
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer)) > 0) {
            myOutput.write(buffer, 0, length);
        }
        // Close the streams136
        myOutput.flush();
        myOutput.close();
        myInput.close();
    }

    /**
     * 解压缩一个文件
     * 
     * @param zipFile
     *            要解压的压缩文件
     * @param folderPath
     *            解压缩的目标目录
     * @throws IOException
     *             当解压缩过程出错时抛出
     */
    public void upZipFile(File zipFile, String folderPath) throws ZipException, IOException {
        File desDir = new File(folderPath);
        if (!desDir.exists()) {
            desDir.mkdirs();
        }

        ZipFile zf = new ZipFile(zipFile);
        for (Enumeration<?> entries = zf.entries(); entries.hasMoreElements();) {
            ZipEntry entry = ((ZipEntry) entries.nextElement());
            InputStream in = zf.getInputStream(entry);
            String str = folderPath + File.separator + entry.getName();
            str = new String(str.getBytes("8859_1"), "GB2312");
            File desFile = new File(str);
            if (!desFile.exists()) {
                File fileParentDir = desFile.getParentFile();
                if (!fileParentDir.exists()) {
                    fileParentDir.mkdirs();
                }
                desFile.createNewFile();
            }
            OutputStream out = new FileOutputStream(desFile);
            byte buffer[] = new byte[1024];
            int realLength;
            while ((realLength = in.read(buffer)) > 0) {
                out.write(buffer, 0, realLength);
            }
            in.close();
            out.close();
        }
    }

}