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Java:如何从方法返回的列表中写入/读取?_Java - Fatal编程技术网

Java:如何从方法返回的列表中写入/读取?

Java:如何从方法返回的列表中写入/读取?,java,Java,我有一个数组和一个从数组中的值创建列表的方法 public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.println("enter all names separated by commas"); String allNames = scanner.nextLine(); String[] lett

我有一个数组和一个从数组中的值创建列表的方法

    public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);    
    System.out.println("enter all names separated by commas");
    String allNames = scanner.nextLine();
    String[] letters = {"a", "b", "c", "d"};;
    convertToList(letters);       
}


public static ArrayList<String> convertToList(String [] array) { 
    ArrayList<String> outputList = new ArrayList<>();
    for (int i = 0; i<array.length; i++) {
        outputList.add(array[i]);
    }
    return outputList;
}

publicstaticvoidmain(字符串[]args){
扫描仪=新的扫描仪(System.in);
System.out.println(“输入所有以逗号分隔的名称”);
String allNames=scanner.nextLine();
字符串[]字母={“a”、“b”、“c”、“d”};;
兑换员(信件);
}
公共静态ArrayList转换器列表(字符串[]数组){
ArrayList outputList=新的ArrayList();
对于(int i=0;i
publicstaticvoidmain(String[]args){
扫描仪=新的扫描仪(System.in);
System.out.println(“输入所有以逗号分隔的名称”);
String allNames=scanner.nextLine();
字符串[]字母={“a”、“b”、“c”、“d”};
ArrayList myList=转换列表(字母);
//打印“a”
System.out.println(myList.get(0));
//加
myList.添加(“e”);
}

您可以使用ArrayList,因为返回类型是给定方法的ArrayList

    ArrayList<String> list = convertToList(letters); 
    list.get(0); //a
    list.add("e"); //add another string
    System.out.println(list); //output:- a b c d e f 
    
ArrayList list=convertToList(字母);
list.get(0);//a
list.add(“e”);//添加另一个字符串
System.out.println(list);//输出:-abcdef
公共类Foo{
公共静态void main(字符串[]args){
扫描仪扫描=新扫描仪(System.in);
System.out.println(“输入所有以逗号分隔的名称”);
列表名称=转换列表(scan.nextLine().split(“,”);
System.out.println();
印刷(姓名);
名称。添加(“John Doe”);
System.out.println();
印刷(姓名);
}
公共静态列表转换器列表(字符串[]名称){
返回数组.asList(名称);
}
私有静态无效打印(列表名称){
for(字符串名称:名称)
System.out.println(名称);
}
}
myList.get(index)
public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);    
    System.out.println("enter all names separated by commas");
    String allNames = scanner.nextLine();
    String[] letters = {"a", "b", "c", "d"};

    ArrayList<String> myList = convertToList(letters);
    // prints "a"
    System.out.println(myList.get(0));
    // add
    myList.add("e");
}
    ArrayList<String> list = convertToList(letters); 
    list.get(0); //a
    list.add("e"); //add another string
    System.out.println(list); //output:- a b c d e f 
    
public class Foo {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        System.out.println("enter all names separated by commas");
        List<String> names = convertToList(scan.nextLine().split(","));

        System.out.println();
        print(names);

        names.add("John Doe");
        System.out.println();
        print(names);
    }

    public static List<String> convertToList(String[] names) {
        return Arrays.asList(names);
    }

    private static void print(List<String> names) {
        for (String name : names)
            System.out.println(name);
    }

}