java 在 Java 中 ConcurrentSkipListMap contains key()方法，示例

在 Java 中 ConcurrentSkipListMap contains key()方法，示例

原文:https://www . geeksforgeeks . org/concurrentskiplistmap-contains key-method-in-Java-with-examples/

java . util . concurrentskiplistmap的 containsKey() 方法是 Java 中的一个内置函数，如果指定的元素出现在这个映射中，它将返回一个真布尔值，否则它将返回 false。

语法:

public boolean containsKey(Object ob)

参数:该函数接受单个强制参数 ob ，该参数指定要测试其在该地图中的存在的键。

返回值:如果该映射包含指定键的映射，则函数返回真。

下面的程序说明了上述方法:

节目 1:

// Java Program Demonstrate containsKey()
// method of ConcurrentSkipListMap

import java.util.concurrent.*;

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

        // Initializing the map
        ConcurrentSkipListMap<Integer, Integer>
            mpp = new ConcurrentSkipListMap<Integer,
                                            Integer>();

        // Adding elements to this map
        for (int i = 1; i <= 5; i++)
            mpp.put(i, i);

        // Checks if 9 is present in the map
        if (mpp.containsKey(9))
            System.out.println("9 is present"
                               + " in the mpp.");
        else
            System.out.println("9 is not present"
                               + " in the mpp.");
    }
}

节目 2:

// Java Program Demonstrate containsKey()
// method of ConcurrentSkipListMap

import java.util.concurrent.*;

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

        // Initializing the map
        ConcurrentSkipListMap<Integer, Integer>
            mpp = new ConcurrentSkipListMap<Integer,
                                            Integer>();

        // Adding elements to this map
        for (int i = 1; i <= 5; i++)
            mpp.put(i, i);

        // Checks if 4 is present in the map
        if (mpp.containsKey(4))
            System.out.println("4 is present"
                               + " in the mpp.");
        else
            System.out.println("4 is not present"
                               + " in the mpp.");
    }
}