Java Vector setElementAt()
Java Vector类的
setElementAt()方法用于替换此Vector指定索引处的组件。
语法
以下是
setElementAt()方法的声明:
public void setElementAt(E obj, int index)
参数
参数 |
说明 |
必需/可选 |
index |
这是将替换元素的指定索引。 |
必需 |
obj |
它是将在指定位置设置的组件。 |
必需 |
返回
此方法的返回类型为
void ,因此,它不返回任何内容。
异常
ArrayIndexOutOfBoundsException -如果数组的索引超出范围,即(索引<0 ||索引> = size()),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 VectorSetElementAtExample1 {
public static void main(String arg[]) {
//Create an empty vector
Vector<Integer> vec = new Vector<>();
//Add elements in the vector
vec.add(1);
vec.add(2);
vec.add(3);
vec.add(4);
vec.add(6);
//Displaying the vector element
System.out.println("Vector element before setElementAt(): " +vec);
//Set Element 5 at 4th index position
vec.setElementAt(5, 4);
//Displaying the vector element again
System.out.println("Vector element after setElementAt(): "+vec);
}
}
输出:
Vector element before setElementAt: [1, 2, 3, 4, 6]
Vector element after setElementAt: [1, 2, 3, 4, 5]
示例2
import java.util.*;
public class VectorSetElementAtExample2 {
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("Android");
vec.add("Python");
vec.add("COBOL");
//Displaying the vector element
System.out.println("Vector element before setElementAt(): " +vec);
//Set "lidihuo" at 3rd index position
vec.setElementAt("lidihuo", 3);
//Displaying the vector element again
System.out.println("Vector element after setElementAt(): "+vec);
}
}
输出:
Vector element before setElementAt: [Java, Android, Python, COBOL]
Vector element after setElementAt: [Java, Android, Python, lidihuo]
示例3
import java.util.*;
public class VectorSetElementAtExample3 {
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(20);
vec.add(30);
//Set 500 at 15th index position
vec.setElementAt(15,500);
//Displaying the vector element
System.out.println("Vector element after set: " +vec);
}
}
输出:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 500 >= 3
at java.base/java.util.Vector.setElementAt(Vector.java:552)
at myPackage.VectorSetElementAtExample3.main(VectorSetElementAtExample3.java:12)