Android 4.1 APP中的static变量即使在APP退出后仍然不会被擦除

public class MainActivity extends Activity {
    private TextView tv;
    private static int i=10;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        tv = (TextView) findViewById(R.id.textView1);
        Button button = (Button) findViewById(R.id.button1);
        button.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                i += 10;
            }
        });
        Button button2 = (Button) findViewById(R.id.button2);
        button2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                tv.setText("i is :" + i);
            }
        });
    }

}