Android Studio reduce memory usage of PC

TextView mIdTextOk = (TextView)findViewById(R.id.idTextOk);
int _nOk = 57;
// number 57 will bold style
mIdTextOk.setText(Html.fromHtml( "OK: "+"<b>"+_nOk+"</b>")); 

import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;

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

		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);
	    	}
	    }
		List sortedByKeys=new ArrayList(map.keySet());
		Collections.sort(sortedByKeys);
		
            // iterate map
	    Set references = map.keySet();
	    Iterator it = references.iterator();
	    while (it.hasNext()) {
	      String key = (String) it.next();
	      String value = map.get(key);
	      System.out.println(key + " = " + value);
	    }
            // or other example how iterate map
	    TreeSet<String> keys = new TreeSet<String>(map.keySet());
	    for (String key : keys) { 
	       String value = map.get(key);
	       System.out.println(key + " = " + value);
	       
	    }		


		
       // check if key exists 	    
//	   if( map.containsKey("two")){
//		System.out.print("two = " + map.get("two"));
//	   }
	}
}
/*
four = vier
one = eine
three = drei
two = zwei
 */

Context context = thisClass.this;
Drawable image = ImageOperations(context,
"//www.okhelp.cz/images/android/ad_4.png"
,"image.jpg");
ImageView imgView;
imgView = (ImageView)findViewById(R.id.idImageView);
imgView.setImageDrawable(image);

	private Drawable ImageOperations(Context ctx, String url, String saveFilename) {
		try {
			InputStream is = (InputStream) this.fetch(url);
			Drawable d = Drawable.createFromStream(is, "src");
			return d;
		} catch (MalformedURLException e) {
			e.printStackTrace();
			return null;
		} catch (IOException e) {
			e.printStackTrace();
			return null;
		}
	}

	public Object fetch(String address) throws MalformedURLException,IOException {
		URL url = new URL(address);
		Object content = url.getContent();
		return content;
	}

// solution 1
ImageView imageView = (ImageView)findViewById(R.id.myimage);
imageView.setImageDrawable(null);
// or
imageView.setImageResource(0);

// solution 2  hide ImageView
imageView.setVisibility(View.INVISIBLE);

// solution 3 resize ImageView 0, 0
 hImageViewSemafor.setLayoutParams(new LinearLayout.LayoutParams(0,0));

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
 */