# Script to start "am" on the device, which has a very rudimentary
# shell.
#
base=/system
export CLASSPATH=$base/framework/BKTools.jar
exec app_process $base/bin com.larack.bktools.BKMain "$@"

CLASSPATH为jar包的路径，com.larack.bktools.BKMain为jar包的main函数所在的类，"$@"表示把当前参数传入到main中。

package com.larackbkapp;

import java.io.DataOutputStream;
import java.io.IOException;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class MainActivity extends Activity {

    private static final String TAG = "AAA";

    private static final String CMD = "run_bktools.sh";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        int result = -1;
        result = execRootCmdSilent(CMD);
        if (-1 == result)
            Toast.makeText(this, "start fail.", Toast.LENGTH_LONG).show();
        else
            Toast.makeText(this, "start success.", Toast.LENGTH_LONG).show();
    }

    public int execRootCmdSilent(String cmd) {
        int result = -1;
        DataOutputStream dos = null;
        try {
            Process p = Runtime.getRuntime().exec("su");
            dos = new DataOutputStream(p.getOutputStream());
            Log.i(TAG, cmd);
            dos.writeBytes(cmd + "\n");
            dos.flush();
            dos.writeBytes("exit\n");
            dos.flush();
            p.waitFor();
            result = p.exitValue();
            Log.i(TAG, "Success execRootCmdSilent(" + cmd + ")=" + result);
        } catch (Exception e) {
            e.printStackTrace();
            Log.e(TAG,
                    "execRootCmdSilent(" + cmd + "),Exception:"
                            + e.getMessage());
        } finally {
            if (dos != null) {
                try {
                    dos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return result;
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}