Java Vector replaceAll()
Java Vector类的
replaceAll()方法用于将列表的每个元素替换为将运算符应用于该元素。
语法
以下是
replaceAll()方法的声明:
public void replaceAll(UnaryOperator<E> operator)
参数
| 参数 |
说明 |
必需/可选 |
| operator |
这是一个运算符，将应用于每个元素。 |
必需 |
返回
replaceAll()方法不返回任何内容。
异常
NullPointerException -如果指定的运算符为null或运算符结果为null值且此列表不允许使用null元素，则此方法引发异常。
兼容版本
Java 1.2及更高版本
示例1
import java.util.*;
public class VectorReplaceAllExample1 {
public static void main(String arg[]) {
//Create an empty vector
Vector<Integer> vec = new Vector<>();
//Add elements in the Vector
vec.add(10);
vec.add(2);
vec.add(30);
vec.add(40);
vec.add(2);
//Display vector elements
System.out.println("Vector elements: " +vec);
//replace all vector element "2" with "20"
Collections.replaceAll(vec, 2, 20);
//Display vector elements after replacement
System.out.println("New vector elements: " + vec);
}
}
输出:
Vector elements: [10, 2, 30, 40, 2]
New vector elements: [10, 20, 30, 40, 20]
示例2
import java.util.*;
public class VectorReplaceAllExample2 {
public static void main(String arg[]) {
//Create an empty vector
Vector<String> vec = new Vector<String>();
//Add elements in the Vector
vec.add("Java");
vec.add("Python");
vec.add("Android");
vec.add("Java");
vec.add("Ruby");
//Display vector elements
System.out.println("Vector elements: " +vec);
//replace all vector element "Java" with "lidihuo"
Collections.replaceAll(vec, "Java", "lidihuo");
//Display vector elements after replacement
System.out.println("New vector elements: " + vec);
}
}
输出:
Vector elements: [Java, Python, Android, Java, Ruby]
New vector elements: [lidihuo, Python, Android, lidihuo, Ruby]
