Android 编码器解码器示例: 解密隐藏的 Flag

package com.example.ilililililil;

import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.Toast; import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity { public static Encoder encoder; public static MainActlvity mainActlvity;

/* access modifiers changed from: protected */
public void onCreate(Bundle bundle) {
    super.onCreate(bundle);
    setContentView((int) R.layout.activity_main);
    encoder = new Encoder();
    mainActlvity = new MainActlvity();
    ((Button) findViewById(R.id.button)).setOnClickListener(new View.OnClickListener((EditText) findViewById(R.id.edit_text)) {
        public final /* synthetic */ EditText f$1;

        {
            this.f$1 = r2;
        }

        public final void onClick(View view) {
            MainActivity.this.lambda$onCreate$0$MainActivity(this.f$1, view);
        }
    });
}

public /* synthetic */ void lambda$onCreate$0$MainActivity(EditText editText, View view) {
    System.out.println(encoder.encode(editText.getText().toString()));
    if (encoder.encode(editText.getText().toString()).equals("棿棢棢棲棥棷棊棐棁棚棨棨棵棢棌")) {
        Toast.makeText(this, "YES", 0).show();
    } else {
        Toast.makeText(this, "NO", 0).show();
    }
}

} package com.example.ilililililil;

public class Encoder { private int key = 123456789;

public String encode(String str) {
    StringBuilder sb = new StringBuilder();
    for (char c : str.toCharArray()) {
        sb.append((char) (c ^ this.key));
    }
    return sb.toString();
}

}