Java 检查元素是否存在列表

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import java.util.ArrayList;// 来 自 nowjava

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public class Main

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{

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   public static void main(String[] args)

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   {

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      // create a new ArrayList of Strings with an initial capacity of 10

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      ArrayList<String> items = new ArrayList<String>(); 

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      items.add("red"); // append an item to the list          

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      items.add(0, "yellow"); // insert "yellow" at index 0

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      // check if a value is in the List

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      System.out.printf("\"red\" is %sin the list%n",

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         items.contains("red") ? "": "not ");

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      // display number of elements in the List

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      System.out.printf("Size: %s%n", items.size());

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      items.remove(1); // remove item at index 1/*来 自 n  o  w  j  a  v  a . c o m*/

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      display(items, "Remove second list element (green):"); 

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      // check if a value is in the List

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      System.out.printf("\"red\" is %sin the list%n",

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         items.contains("red") ? "": "not ");

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      // display number of elements in the List

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      System.out.printf("Size: %s%n", items.size());

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   } 

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   // display the ArrayList's elements on the console

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   public static void display(ArrayList<String> items, String header)

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   {

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