相关疑难解决方法(0)

尝试从List中删除元素时,为什么会出现UnsupportedOperationException?

我有这个代码:

public static String SelectRandomFromTemplate(String template,int count) {
   String[] split = template.split("|");
   List<String> list=Arrays.asList(split);
   Random r = new Random();
   while( list.size() > count ) {
      list.remove(r.nextInt(list.size()));
   }
   return StringUtils.join(list, ", ");
}
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我明白了:

06-03 15:05:29.614: ERROR/AndroidRuntime(7737): java.lang.UnsupportedOperationException
06-03 15:05:29.614: ERROR/AndroidRuntime(7737):     at java.util.AbstractList.remove(AbstractList.java:645)
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这怎么会是正确的方法?Java.15

java exception list arraylist

444
推荐指数
7
解决办法
37万
查看次数

删除arrayList,java.lang.UnsupportedOperationException中的项

我想在数组列表选择位置删除项目

我的代码是

    List<String> historylist = Arrays.asList(history);
    if (historylist.size()>=3){
        System.out.print("*************************************************");
        Log.i(MyContants.StoredHistory_TAG,"StoredHistory size========="+ String.valueOf(historylist.size()));
        String removePosition=historylist.get(2);
        historylist.remove(removePosition);
    }
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但是我得到了一个Exception UnsupportedOperationException

错误

    12-20 09:16:27.680: I/StoredHistory Class(5715): StoredHistory size=========3
    12-20 09:16:27.680: D/AndroidRuntime(5715): Shutting down VM
    12-20 09:16:27.684: W/dalvikvm(5715): threadid=1: thread exiting with uncaught exception (group=0x4001d7d0)
    12-20 09:16:27.688: E/AndroidRuntime(5715): FATAL EXCEPTION: main
    12-20 09:16:27.688: E/AndroidRuntime(5715): java.lang.RuntimeException: Unable to start activity ComponentInfo{****PACKAGE NAME*****}: java.lang.UnsupportedOperationException
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
    12-20 09:16:27.688: E/AndroidRuntime(5715):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
    12-20 09:16:27.688: …
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android arraylist

4
推荐指数
2
解决办法
5102
查看次数

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