Convert String array to ArrayList [duplicate]

using Arrays.asList

import java.util.Arrays;  
import java.util.List;  
import java.util.ArrayList;  
public class StringArrayTest  
{  
   public static void main(String[] args)  
   {  
      String[] words = {"ace", "boom", "crew", "dog", "eon"};  

      List<String> wordList = Arrays.asList(words);  

      for (String e : wordList)  
      {  
         System.out.println(e);  
      }  
   }  
}

String array 的一些用法

ublic class Program {
    public static void main(String[] args) {

 // This string array contains three values.
 String[] values = { "cat", "dog", "spider" };

 // Combine these strings together.
 String joined = String.join(",", values);
 System.out.println(joined);

 // Separate the combined string with split.
 String[] values2 = joined.split(",");
 for (String v : values2) {
     System.out.println(v);
 }
    }
}

Output

cat,dog,spider
cat
dog
spider

import java.util.Arrays;

public class Program {
    public static void main(String[] args) {

 // Create a string array with four values.
 String[] values = new String[4];
 values[0] = "zoo";
 values[1] = "marina";
 values[2] = "amphitheatre";
 values[3] = "colloseum";

 // Sort the strings.
 Arrays.sort(values);

 // Display the sorted strings.
 for (String v : values) {
     System.out.println(v);
 }
    }
}

Output

amphitheatre
colloseum
marina
zoo

================================================================

ArrayList是JAVA當中的一個類別

與Array差在於因為他是一個寫好的類別,有很多可以直接用的程式碼,所以很方便

使用方法:

1.建構

ArrayList<String> myList = new ArrayList<String>();  //指定是String的型態

ArrayList myList = new ArrayList(); // 也可以不指定

2.加入元素



String s = new String();

myList.add(s);




3.查詢list大小

int theSize = myList.size();




4.查詢特定元素

boolean isIn = myList.contains(s);  //若用上面的例子 因為有s字串 所以回傳true




5.查詢特定元素位置

int idx = myList.indexOf(s); //會回傳0 表第0個位置






6.判斷List是否為空

boolean empty = myList.isEmpty(); //因為有一個元素 會回傳false




7.刪除特定元素

myList.remove(s);