Java Java.util.EnumMap.equals()用法及代碼示例

描述

這個java.util.EnumMap.equals(Object o)方法比較指定的對象與此映射是否相等。兩個對象都必須是映射。

聲明

以下是聲明java.util.EnumMap.equals()方法

public boolean equals(Object o)

參數

oâˆ' 要與此映射進行相等性比較的對象。

返回值

如果指定的對象等於此映射，則此方法返回 true

異常

NA

示例

下麵的例子展示了 java.util.EnumMap.equals() 方法的用法。

package com.tutorialspoint;

import java.util.*;

public class EnumMapDemo {

   // create an enum
   public enum Numbers {
      ONE, TWO, THREE, FOUR, FIVE
   };

   public static void main(String[] args) {
   
      EnumMap<Numbers, String> map1 =
         new EnumMap<Numbers, String>(Numbers.class);

      EnumMap<Numbers, String> map2 =
      new EnumMap<Numbers, String>(Numbers.class);

      // associate values in map1
      map1.put(Numbers.ONE, "1");
      map1.put(Numbers.TWO, "2");
      map1.put(Numbers.THREE, "3");
      map1.put(Numbers.FOUR, "4");

      // associate values in map2
      map2.put(Numbers.ONE, "1");
      map2.put(Numbers.TWO, "2");
      map2.put(Numbers.THREE, "3");
      map2.put(Numbers.FOUR, "4");

      // print the maps
      System.out.println("map1:" + map1);
      System.out.println("map2:" + map2);

      // check for equality between maps
      boolean equal = map1.equals(map2);

      // print the result
      System.out.println("Map1 and map 2 are equal:" + equal);

      // add one more value in map2
      map2.put(Numbers.FIVE, "5");

      // check for equality between maps
      equal = map1.equals(map2);

      // print the result
      System.out.println("Map1 and map 2 are equal:" + equal);
   }
}

讓我們編譯並運行上麵的程序，這將產生以下結果——

map1:{ONE=1, TWO=2, THREE=3, FOUR=4}
map2:{ONE=1, TWO=2, THREE=3, FOUR=4}
Map1 and map 2 are equal:true
Map1 and map 2 are equal:false