Java EnumMap remove()
Java EnumMap类的
remove()方法用于从EnumMap中删除给定键的映射。
语法
public V remove(Object key)
参数
key-要从映射中删除其映射的键。
返回
此方法返回与给定键关联的旧值；如果给定键没有映射，则返回null。
异常
NA
示例1
import java.util.*;
public class EnumMapRemoveExample1 {
// create an enum
public enum Tutorial {
Java, CSS, Python, Android, Javascript
};
public static void main(String[] args) {
EnumMap<Tutorial, String> map = new EnumMap<Tutorial, String>(Tutorial.class);
map.put(Tutorial.Java, "1");
map.put(Tutorial.CSS, "2");
map.put(Tutorial.Python, "3");
map.put(Tutorial.Android, "4");
System.out.println("Map: "+map);
map.remove(Tutorial.CSS);
System.out.println("Updated Map: "+map);
}
}
输出:
Map: {Java=1, CSS=2, Python=3, Android=4}
Updated Map: {Java=1, Python=3, Android=4}
示例2
import java.util.*;
public class EnumMapRemoveExample2 {
// create an enum
public enum Days {
Monday,Tuesday, Wednesday, Thursday
};
public static void main(String[] args) {
EnumMap<Days, String> map = new EnumMap<Days, String>(Days.class);
map.put(Days.Monday, "1");
map.put(Days.Tuesday, "2");
map.put(Days.Wednesday, "3");
System.out.println("Map: "+map);
map.remove(Days.Thursday);
System.out.println("Updated Map: "+map);
}
}
输出:
Map: {Monday=1, Tuesday=2, Wednesday=3}
Updated Map: {Monday=1, Tuesday=2, Wednesday=3}
