比較兩個陣列列表並從中刪除多餘的元素

Question

如何比較兩個陣列列表？我有一個sdCoverList數組和thumbnailList數組。

02-04 11:05:05.210: I/System.out(4035): HASHED THUMBNAIL[-2122410790, 2043473787, 1914391068, 1785308349, 1656225630, 1527142911, 1398060192, 1268977473, 1139894754, 1010812035, 1242943301, 1113860582, 984777863, 855695144, 726612425, 597529706, 468446987, 339364268, 210281549] 
02-04 11:05:05.210: I/System.out(4035): SD COVER LIST[-2122410790, 2043473787, 1914391068, 1785308349, 1268977473, 1656225630, 1527142911, 1139894754, 1398060192, 1010812035, 1242943301, 1113860582, 984777863, 855695144, 726612425, 597529706, 468446987, 339364268, 210281549, 717409028] 

在我的SD蓋名單，我有我想要刪除掉額外的價值，但首先我得先用thumbnailList陣列比較。如果兩者都具有相同的元素，則不要執行任何操作，但是如果有額外的內容，請將其從SD卡中移除。

我的數組列表

爲sdCoverList：

// CHECK DIRECTORY BEFORE DELETING THEM 
      File strPath = new File(Environment.getExternalStorageDirectory() + folderName+"/Covers"); 
      File yourDir = new File(strPath, ""); 
      if(yourDir.length()!=0) 
      for (File f : yourDir.listFiles()) { 
       if (f.isFile()) 
       { 
        String name = f.getName(); 
        sdCoverList.add(name); 
        //System.out.println(sdCoverList); 
       } 

爲hashedthumbnail

for (int a=0;a<=thumbnailList.size()-1;a++) 
     { 
      String hashed = String.valueOf(thumbnailList.get(a).hashCode()); 
      Log.d("hashed",hashed); 
      hashedThumbnail.add(hashed); 
     } 

Answer 1

List<String> sdCoverList = new ArrayList<String>(); 
sdCoverList.add("-2122410790"); 
sdCoverList.add("2043473787"); 
sdCoverList.add("717409028"); 

List<String> hashedThumbnail = new ArrayList<String>(); 
hashedThumbnail.add("-2122410790"); 
hashedThumbnail.add("2043473787"); 

System.out.println("sdCover List: " + sdCoverList); 
System.out.println("hashedThumbnail List: " + hashedThumbnail); 


List<String> temp = new ArrayList<String>(); 
temp.addAll(sdCoverList); 
temp.removeAll(hashedThumbnail); 

System.out.println("temp List: " + temp); 

sdCoverList.removeAll(temp); 

System.out.println("sdCover List: " + sdCoverList); 

的輸出將是

sdCover List: [-2122410790, 2043473787, 717409028] 
hashedThumbnail List: [-2122410790, 2043473787] 
temp List: [717409028] 
sdCover List: [-2122410790, 2043473787]