Java Vector removeAll()
Java向量类的
removeAll()方法从向量中删除了指定元素中存在的所有元素
语法
以下是
removeAll()方法的声明:
public boolean removeAll(Collection<?> c)
参数
| 参数 |
说明 |
必需/可选 |
| c |
它是元素的集合，将从向量中删除。 |
必需 |
返回
如果引导程序改变了Vector ，则
removeAll()方法将返回true。
异常
NullPointerException -如果向量包含一个或多个null元素并且指定的集合不支持null元素，或者如果
兼容版本
Java 1.2及更高版本
示例1
import java.util.Vector;
public class VectorRemoveAllExample1 {
public static void main(String arg[]) {
//Create an empty Vec1
Vector<Integer> vec1 = new Vector<>();
//Add elements in the Vector1
vec1.add(1);
vec1.add(2);
vec1.add(3);
vec1.add(4);
vec1.add(5);
//Displaying the Vector elements
System.out.println("Vector: " + vec1);
System.out.println("Removing all the elements");
//use removeAll() method
vec1.removeAll(vec1);
//Display the size of the Vector
System.out.println("Size of the vector: "+vec1.size());
}
}
输出:
Vector: [1, 2, 3, 4, 5]
Removing all the elements
Size of the vector: 0
示例2
import java.util.Vector;
public class VectorRemoveAllExample2 {
public static void main(String arg[]) {
//Create an empty Vec1
Vector<String> vec1 = new Vector<String>();
//Add elements in the Vector1
vec1.add("A");
vec1.add("B");
vec1.add("C");
vec1.add("10");
vec1.add("20");
//Displaying the Vector1 elements
System.out.println("Vector: " + vec1);
//Create an empty Vec2
Vector<String> vec2 = new Vector<String>();
//Add elements in the Vector2
vec2.add("A");
vec2.add("B");
vec2.add("C");
//use removeAll() method
boolean changed = vec1.removeAll(vec2);
//Print the result
if (changed)
System.out.println("Collection removed");
else
System.out.println("Collection not removed");
//Display the final Vector
System.out.println("final Vector: " + vec1);
}
}
输出:
Vector: [A, B, C, 10, 20]
Collection removed
final Vector: [10, 20]
