java中String数组和List的互相转化

1.List转String数组

方法一:

//先准备一个List

List<String> testList=new ArrayList<>();

testList.add("a");

testList.add("b");

testList.add("c");

//List转String

String[] strs1=testList.toArray(new String[testList.size()]);

for(String s:strs1){

   System.out.println(s);

}

方法二：

//先准备一个List

List<String> testList=new ArrayList<>();

testList.add("a");

testList.add("b");

testList.add("c");

//List转String

String[] strs2 = new String[testList.size()];

for(int i=0;i<testList.size();i++){

   strs2[i]=testList.get(i);

}

for(String s:strs2){

  System.out.println(s);

}

二：String数据转List

方法一：

//准备一个String数组

String[] strs = {"aa","bb","cc"};

//String数组转List

List<String> strsToList1= Arrays.asList(strs);

for(String s:strsToList1){

 System.out.println(s);

}

方法二：

//准备一个String数组

String[] strs = {"aa","bb","cc"};

//String数组转List

List<String> strsToList2=new ArrayList<>();

Collections.addAll(strsToList2,strs);

for(String s:strsToList2){

   System.out.println(s);

}

方法三：

//准备一个String数组

String[] strs = {"aa","bb","cc"};

//String数组转List

List<String> strsToList3=new ArrayList<>();

for(String s:strs){

    strsToList3.add(s);

}

for(String s:strsToList3){

    System.out.println(s);

}