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package com.example.yokindemo;import java.io.BufferedReader;import java.io.DataOutputStream;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import android.app.Activity;import android.content.ComponentName;import android.content.Context;import android.content.Intent;import android.content.pm.PackageInfo;import android.content.pm.PackageManager;import android.net.Uri;import android.os.Bundle;import android.os.Environment;import android.util.Log;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.Toast;public class MainActivity extends Activity implements OnClickListener {	private static final String TAG = "MainActivity";	private Button jia, uninst;	@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		setContentView(R.layout.activity_main);		copyApkFromAssets(this, "jia.apk", Environment				.getExternalStorageDirectory().getAbsolutePath() + "/jia.apk");		jia = (Button) findViewById(R.id.jia);		jia.setOnClickListener(this);				uninst = (Button) findViewById(R.id.button1);		uninst.setOnClickListener(this);	}	public boolean install(String apkPath) {		boolean result = false;		DataOutputStream dataOutputStream = null;		BufferedReader errorStream = null;		try {			Process process = Runtime.getRuntime().exec("su");			dataOutputStream = new DataOutputStream(process.getOutputStream());			String argString = "pm install -r " + apkPath + "\n";			String command = new String(argString.getBytes(),"UTF-8");			dataOutputStream.write(command.getBytes());			dataOutputStream.flush();			dataOutputStream.writeBytes("exit\n");			dataOutputStream.flush();			process.waitFor();			errorStream = new BufferedReader(new InputStreamReader(					process.getErrorStream()));			String msg = "";			String line;			while ((line = errorStream.readLine()) != null)				msg += line;			if (!msg.contains("Failure"))				result = true;		} catch (Exception e) {			Log.e(TAG, e.getMessage(), e);		} finally {			try {				if (dataOutputStream != null)					dataOutputStream.close();				if (errorStream != null)					errorStream.close();			} catch (IOException e) {				Log.e(TAG, e.getMessage(), e);			}		}		return result;	}		private int getAPKVersion(){		String filePath = Environment				.getExternalStorageDirectory().getAbsolutePath() + "/jia.apk";  		PackageManager packageManager = getPackageManager();  		PackageInfo packageInfo = packageManager.getPackageArchiveInfo(filePath, PackageManager.GET_ACTIVITIES);		return packageInfo.versionCode;	}		private void uninstallAPK(){		Uri packageURI = Uri.parse("package:com.example.jia");   		Intent uninstallIntent = new Intent(Intent.ACTION_DELETE, packageURI);   		startActivity(uninstallIntent);	}	private boolean isAppInstalled(String packName) {		PackageManager pm = getPackageManager();		boolean installed = false;		try {			Log.d(TAG, "apk="+getAPKVersion());			PackageInfo pi = pm.getPackageInfo(packName, PackageManager.GET_ACTIVITIES);			Log.d(TAG, "ver="+pi.versionCode);			installed = true;		} catch (PackageManager.NameNotFoundException e) {			installed = false;		}		return installed;	}	@Override	public void onClick(View v) {		switch (v.getId()) {		case R.id.jia:			if (isAppInstalled("com.example.jia")) {				Toast.makeText(MainActivity.this, "jia已经安装", Toast.LENGTH_LONG).show();			} else {				Toast.makeText(MainActivity.this, "jia还没安装", Toast.LENGTH_LONG).show();			}			Intent intent = new Intent();			ComponentName cn = new ComponentName("com.example.jia",					"com.example.jia.MainActivity");			intent.setComponent(cn);			intent.setAction("android.intent.action.MAIN");			try {				startActivityForResult(intent, RESULT_OK);			} catch (Exception e) {				if (!install(Environment.getExternalStorageDirectory()						.getAbsolutePath() + "/jia.apk")) {					Intent intent1 = new Intent(Intent.ACTION_VIEW);					intent1.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);					intent1.setDataAndType(							Uri.parse("file://"									+ Environment.getExternalStorageDirectory().getAbsolutePath()									+ "/jia.apk"), "application/vnd.android.package-archive");					startActivity(intent1);				}			}			break;		case R.id.button1:			Log.d(TAG, "button1");			uninstallAPK();			break;		default:			break;		}	}	public boolean copyApkFromAssets(Context context, String fileName, String path) {		boolean copyIsFinish = false;		try {			InputStream is = context.getAssets().open(fileName);			File file = new File(path);			file.createNewFile();			FileOutputStream fos = new FileOutputStream(file);			byte[] temp = new byte[1024];			int i = 0;			while ((i = is.read(temp)) > 0) {				fos.write(temp, 0, i);			}			fos.close();			is.close();			copyIsFinish = true;		} catch (IOException e) {			e.printStackTrace();		}		return copyIsFinish;	}}

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