Wie mache ich einen Unterschied zwischen 2 ArrayLists

Question

Ich mache einen Webserver, der Checker-ähnliche Kacheln generiert Bilder auf Java.

Die Klasse, die Modelle der Checker ist:

package app.app.image; 


import app.app.image.iterate.ImageElementVisitorInterface; 
import app.app.image.tiles.Tile; 

import java.awt.*; 
import java.util.ArrayList; 
import org.apache.commons.collections4.CollectionUtils; 


/** 
* Created by pcmagas on 5/10/2016. 
* 
* Methos that Implements a Checkerboard with multiple color tiles 
*/ 
public class Checker implements ImageElement 
{ 

    /** 
    * The tiles that can be used to Draw the checker 
    */ 
    private ArrayList<Tile> availableTiles=null; 

    /** 
    * The grid where the tiles are drawn 
    */ 
    private Tile[][] checkerGrid=null; 



    /** 
    * The checker width 
    */ 
    private int width=0; 

    /** 
    * The checker Height 
    */ 
    private int height=0; 

    private int tileSize=0; 

    /** 
    * Creates a new Checker 
    * @param width the checker's width 
    * @param height the checker's height 
    */ 
    public Checker(int width, int height) 
    { 
     availableTiles= new ArrayList<Tile>(); 

     this.setHeight(height); 
     this.setWidth(width); 
    } 

    /** 
    * @param height The checker's height 
    */ 
    public void setHeight(int height) 
    { 
     this.height=height; 
    } 

    /** 
    * @return The checker's height 
    */ 
    public int getHeight() 
    { 
     return this.height; 
    } 

    /** 
    * Seth the tile width 
    * @param width 
    */ 
    public void setWidth(int width) 
    { 
     this.width=width; 
    } 

    /** 
    * Returns how wide is the tile 
    * @return 
    */ 
    public int getWidth() 
    { 
     return this.width; 
    } 

    /** 
    * Method that Allows us to append a tile to the Checker 
    */ 
    public void addTile(Tile t) throws Exception 
    { 
     if(this.tileSize >0 && t.getSize()!= this.tileSize) 
     { 
      throw new Exception("The tile does not have the same size with the orthers"); 
     } 
     else if(!this.availableTiles.contains(t)) 
     { 
      this.availableTiles.add(t); 
      this.tileSize=t.getSize(); 
     } 
    } 


    /** 
    * Method that initializes the grid for the checker 
    */ 
    private void initGrid() 
    { 
     if(this.checkerGrid==null) 
     { 
      int width = this.width/this.tileSize; 
      int height = this.height/this.tileSize; 

      this.checkerGrid=new Tile[height][width]; 
     } 
    } 

    /** 
    * Method that selects a tile during the grid generation 
    * @param top The tile that is on top of the current tile 
    * @param previous The tile that is on previously from the current tile 
    * 
    * @return The correctly selected tile 
    */ 
    private Tile selectTile(Tile top,Tile previous) 
    { 
     ArrayList<Tile> tilesNotToUse=new ArrayList<Tile>(); 

     if(top==null) 
     { 
      tilesNotToUse.add(top); 
     } 

     if(previous==null) 
     { 
      tilesNotToUse.add(previous); 
     } 

     //TODO: Create a diff Between this.availableTiles and tilesNotToUse 
     return new Tile(Color.black,10,this); 
    } 

    @Override 
    public void draw(ImageElementVisitorInterface visitor) 
    { 
     this.initGrid(); 

     for(int i=0;i<this.checkerGrid.length;i++) 
     { 
      for(int j=0;j<this.checkerGrid[i].length;j++) 
      { 
       Tile top=(i>0)?this.checkerGrid[i-1][j]:null; 
       Tile previous=(j>0)?this.checkerGrid[i][j-1]:null; 

       Tile currentTile=this.selectTile(top,previous); 
       this.checkerGrid[i][j]= currentTile; 

       currentTile.draw(visitor); 
      } 
     } 

    } 

} 

Bitte Ich habe einige do-not-Know-hot-to-do an dieser Methode:

/** 
* Method that selects a tile during the grid generation 
* @param top The tile that is on top of the current tile 
* @param previous The tile that is on previously from the current tile 
* 
* @return The correctly selected tile 
*/ 
private Tile selectTile(Tile top,Tile previous) 
{ 
    ArrayList<Tile> tilesNotToUse=new ArrayList<Tile>(); 

    if(top==null) 
    { 
     tilesNotToUse.add(top); 
    } 

    if(previous==null) 
    { 
     tilesNotToUse.add(previous); 
    } 


    //TODO: Create a diff Between this.availableTiles and tilesNotToUse 
    return new Tile(Color.black,10,this); 
} 

Und ich tun möchte, ein Unterschied zwischen this.availableTiles und tileNotToUse. Ich habe die CollectionUtils gesehen, aber ich kann nicht herausfinden, wie es geht. Ich möchte ein ähnliches Ergebnis mit PHP http://php.net/manual/en/function.array-diff.php

Answer 1

erreichen Sie können list1.removeAll (list2); Java Docs So wird Ihre list1 nur das haben, was zu list1 gehört und nicht zu list2. Und umgekehrt, wenn du willst.