小编Joh*_*hnH的帖子

我有两个字符串数组中ar1和ar2,我从文件中读取输入和存储阵列,ar1包含

Cat
Lam
Orange
Kam
Ramveer
None
Tue
Apple

ar2包含

Dog
elephant
Kam
Monday
Parrot
Queen
Ramveer
Tuesday
Xmas

我试图按字母顺序排序数组,我正在使用Array.sort(),但获得异常

Exception in thread "main" java.lang.NullPointerException
at java.util.ComparableTimSort.binarySort(ComparableTimSort.java:232)
at java.util.ComparableTimSort.sort(ComparableTimSort.java:176)
at java.util.ComparableTimSort.sort(ComparableTimSort.java:146)
at java.util.Arrays.sort(Arrays.java:472)
at CompareArrays.pr1(CompareArrays.java:51)
at CompareArrays.main(CompareArrays.java:86)

Java结果:1成功建立(总时间:0秒)

码

File file1= new File("C:\\Users\\Ramveer\\Desktop\\updates\\f1.txt");
File file2=new File("C:\\Users\\Ramveer\\Desktop\\updates\\f2.txt");
Scanner sc1=new Scanner(file1);
Scanner sc2=new Scanner(file2);
while(sc1.hasNextLine()){
ar1[c1]=sc1.nextLine();
c1++;
}

while(sc2.hasNextLine()){
ar2[c2]=sc2.nextLine();
c2++;
 }
  Arrays.sort(ar1);
  for(int k=0;k<c1;k++){
      System.out.println(ar1[k]);}

  }

任何帮助都会很棒.谢谢!