Android Studio lock unlock file make read only or writable

<include  layout="@layout/my_layout" android:id="@+id/idMyLayout" />

import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

public class MainClass {
	public static void main(String[] arg) {
		String[] arrayOfString = {"nothing", "Hello", "people"
				, "bye-bye", "hello", "world!", "End" };
		   
                   List<String> arrayList = new LinkedList<String>();
                  
                   for(String s: arrayOfString)
		     arrayList.add(s);

		    Collections.sort(arrayList);
		    // foreach
		    for (String str: arrayList)
		      System.out.println(str);
		    
		    Object objMin = Collections.min(arrayList);
		    System.out.println("Min is: " + objMin);
		    
		    Object objMax = Collections.max(arrayList);
		    System.out.println("Max is: " + objMax);
		    
		    int index = Collections.binarySearch(arrayList, "people");
		    System.out.println("Index of people is: " + index);
		    // print word on index 5
		    System.out.println("Index 5 is: " + arrayList.get(5));
                    String sItem = arrayList.get(5); // get item from index 5 to string
		    
		  }
}
/*
End
Hello
bye-bye
hello
nothing
people
world!
Min is: End
Max is: world!
Index of people is: 5
Index 5 is: people
*/

// Context instead Activity as a parameter
@Override
public void onAttach(Context context) {
    super.onAttach(context);

    Activity a;

    if (context instanceof Activity){
        a=(Activity) context;
    }

}

OnNoteClickedListener listener;
/* old emxample of usage
	@Override
	public void onAttach(Activity activity) {
		super.onAttach(activity);
		try {
			listener = (OnNoteClickedListener) activity;
		} catch (ClassCastException e) {
			throw new ClassCastException(activity.toString()
					+ " must implement OnNoteClickedListener");
		}
	}
*/
// new version of code
	@Override
	public void onAttach(Context context) {
		super.onAttach(context);

		Activity a;

		if (context instanceof Activity){
			a=(Activity) context;
			try {
				listener = (OnNoteClickedListener) a;
			} catch (ClassCastException e) {
				throw new ClassCastException(a.toString()
						+ " must implement OnNoteClickedListener");
			}
		}

	}

import java.util.Map;
import java.util.TreeMap;

public class MainClass {
	public static void main(String[] arg) {
		
		// english;germany dictionary
		String[] arrayOfString = { "one;eine", "two;zwei", "three;drei" };

		Map<String, String> map = new TreeMap<String, String>();
	    
		for(String s: arrayOfString){
	    	String[] array = s.split(";");
	    	String sKey ="", sValue="";
	    	if(array.length > 1){
	    	sKey = array[0]; sValue = array[1];
	    		map.put(sKey, sValue);
	    	}
	    }

       // check if key exists 	    
	   if( map.containsKey("two")){
		System.out.print("two = " + map.get("two"));
	   }
	}
}
/*
two = zwei
 */