Java Vector addAll()
addAll() Java Vector类方法将指定集合中的所有元素插入到对象的末尾。正在使用的向量。元素的顺序将与指定集合的迭代器返回的顺序相同。有
两种类型的Java addAll()方法，可以根据其参数进行区分。这些是:
Java Vector addAll(Collection <？extendsE> c)方法
Java Vector addAll(int index，Collection <？extends E> c)方法
addAll(Collection <？extends E> c)方法:
此方法用于将指定集合中的所有元素附加到此元素的末尾向量。
addAll(int index，Collection <？extends E> c)方法:
此方法用于将所有元素插入指定集合中
语法:
下面是
addAll()方法的声明:
public boolean addAll(Collection<? extends E> c)
public boolean addAll(int index, Collection<? extends E> c)
参数:
| 参数 |
说明 |
必需/可选 |
| index |
这是我们将从指定集合中插入第一个元素的索引。 |
必需 |
| c |
它是将插入到此Vector中的元素。 |
必需 |
返回:
如果此Vector由于调用而发生更改，则
addAll()方法将返回true。
异常:
NullPointerException -如果指定的集合为null，则此方法引发异常。
IndexOutOfBoundsException -如果数组的索引超出范围，即(index <0 || index> size())，则此方法引发异常。
兼容性版本:
Java 1.2及更高版本
示例1:
import java.util.*;
public class VectorAddAllExample1 {
public static void main(String arg[]) {
//Create an empty arrayList1
ArrayList<Integer> arrlist1 = new ArrayList<Integer>(4);
//Add elements into an arrayList1
arrlist1.add(1);
arrlist1.add(2);
arrlist1.add(3);
System.out.println("List of first arrayList: "+arrlist1);
//Create an empty arrayList2
ArrayList<Integer> arrlist2 = new ArrayList<Integer>(4);
//Add elements into an arrayList2
arrlist2.add(4);
arrlist2.add(5);
arrlist2.add(6);
System.out.println("List of second arrayList: "+arrlist2);
//Appending all elements
arrlist1.addAll(arrlist2);
//Printing the final arrayList
System.out.println("final arrayList: "+arrlist1);
}
}
输出:
List of first arrayList: [1, 2, 3]
List of second arrayList: [4, 5, 6, 7]
final arrayList: [1, 2, 3, 4, 5, 6, 7]
示例2:
import java.util.*;
public class VectorAddAllExample2 {
public static void main(String arg[]) {
//Create a first empty vector
Vector<String> vec1 = new Vector<>(4);
//Add elements in the first vector
vec1.add("E");
vec1.add("F");
vec1.add("G");
vec1.add("H");
//Create a second empty vector
Vector<String> vec2 = new Vector<>(4);
//Add elements in the second vector
vec2.add("A");
vec2.add("B");
vec2.add("C");
vec2.add("D");
//Add elements of the vec2 at 1st element position in the vec1
vec1.addAll(0, vec2);
//Printing the final vector after appending
System.out.println("final vector list: "+vec1);
}
}
输出:
final vector list: [A, B, C, D, E, F, G, H]
示例3:
import java.util.*;
public class VectorAddAllExample3 {
public static void main(String arg[]) {
//Create a first empty vector
Vector<String> vec1 = new Vector<>(2);
//Add elements in the first vector
vec1.add("Java");
vec1.add("Android");
//Create a second empty vector
Vector<String> vec2 = new Vector<>(2);
//Add elements in the second vector
vec2.add("Python");
vec2.add("PHP");
//Add elements of the vec2 at 1st element position in the vec1
vec1.addAll(vec2);
//Printing the final vector after appending
System.out.println("final vector list: "+vec1);
}
}
输出:
final vector list: [Java, Android, Python, PHP]
示例4:
import java.util.*;
public class VectorAddAllExample4 {
public static void main(String arg[]) {
//Create a first empty vector
Vector<Integer> vec1 = new Vector<>(2);
//Add elements in the first vector
vec1.add(11);
vec1.add(44);
//Create a second empty vector
Vector<Integer> vec2 = new Vector<>(2);
//Add elements in the second vector
vec2.add(22);
vec2.add(33);
//Add elements of the vec2 at 3rd element position in the vec1
vec1.addAll(3, vec2);
//Printing the final vector after appending
System.out.println("final vector list: "+vec1);
}
}
输出:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Array index out of range: 3
at java.base/java.util.Vector.addAll(Vector.java:1064)
at myPackage.VectorAddAllExample4.main(VectorAddAllExample4.java:16)
