实现 AttributeList API 的Java程序

AttributeList可用于在单个调用中获取和设置多个 MBean 属性。它是一个只能包含属性的 ArrayList。 AttributeLists 必须在外部同步。

宣言：

public class AttributeList extends ArrayList
{
  // code
}

AttributeList API 的实现类：

• 可序列化
• 可克隆
• 可迭代的
• 收藏
• 列表
• 随机访问

构造函数：

1. AttributeList() –构造一个新的空属性列表。
2. AttributeList(AttributeList list) –从另一个属性列表构造一个新属性。
3. AttributeList(int initialCapacity) –构造一个具有指定初始容量的新空属性列表。

方法：

1. add(Attribute object) –将属性附加到列表的方法。
2. void add(int index, Attribute object) –将新属性插入列表中指定索引处的方法。
3. boolean addAll(AttributeList list) –将属性附加到列表的方法。
4. boolean addAll(int index, AttributeList list) –在指定索引处插入传递列表中所有属性的方法。
5. void set(int index, Attribute object) –在指定索引处更改属性的方法。

Java

// Java program to implement AttributeList API
  
import java.util.Collection;
import java.util.List;
import javax.management.Attribute;
import javax.management.AttributeList;
  
public class AttributeListImpl {
    private AttributeList attributeList;
  
    // constructor for creating an empty AttributeList
    public AttributeListImpl()
    {
        attributeList = new AttributeList();
    }
  
    // constructor for creating an AttributeList containing
    // the elements of the AttributeList specified, in the
    // order in which they are returned by the
    // AttributeList's iterator.
  
    public AttributeListImpl(AttributeList list)
    {
        attributeList = new AttributeList();
    }
  
    // constructor for creating an AttributeList with the
    // specified initial capacity
    public AttributeListImpl(int initialCapacity)
    {
        attributeList = new AttributeList(initialCapacity);
    }
  
    // constructor for creating an AttributeList
    // containing the elements of the List
    // specified.
  
    public AttributeListImpl(List list)
    {
        attributeList = new AttributeList();
    }
  
    // this method appends an Attribute to the list
    public void add(Attribute object)
    {
        attributeList.add(object);
    }
  
    // this method inserts an attribute at a specified
    // position
    public void add(int index, Attribute object)
    {
        attributeList.add(index, object);
    }
  
    // this method inserts an specified element at
    // a specified position
    public void add(int index, Object element)
    {
        attributeList.add(index, element);
    }
  
    // this method appends a specified element to the list
    public boolean add(Object element)
    {
        return attributeList.add(element);
    }
  
    // this method appends all the elements of a
    // given list in the AttributeList.
    public boolean addAll(AttributeList list)
    {
        return attributeList.addAll(list);
    }
  
    // this method will appends all of the
    // elements of the given Collection
    // in the AttributeList.
    public boolean addAll(Collection c)
    {
        return attributeList.addAll(c);
    }
  
    // Inserts all of the elements in the AttributeList
    // specified into this list, starting at the specified
    // position, in the order in which they are returned by
    // the Iterator of the AttributeList specified.
    public boolean addAll(int index, AttributeList list)
    {
        return attributeList.addAll(index, list);
    }
  
    // this method will add all of the elements of the
    // given collection at a the specified index
    public boolean addAll(int index, Collection c)
    {
        return attributeList.addAll(index, c);
    }
  
    // this method Return a view of this list as a
    // List
    public List asList()
    {
        return attributeList.asList();
    }
  
    // this method will set the element at a given position
    public void set(int index, Attribute element)
    {
        attributeList.set(index, element);
    }
  
    // this method will replace the element at the specified
    // position in this list with the given element
    public Object set(int index, Object element)
    {
        return attributeList.set(index, element);
    }
  
    public static void main(String[] arg)
    {
        // creating object for AttributeListImpl object
        AttributeListImpl attributeList
            = new AttributeListImpl();
  
        attributeList.add(new Attribute("rose", 1));
        attributeList.add(new Attribute("sun-flower", 2));
        attributeList.add(new Attribute("tulip", 3));
        attributeList.add(new Attribute("orchid", 4));
        attributeList.add(new Attribute("marie-gold", 5));
        attributeList.add(new Attribute("hibiscus", 0));
  
        System.out.println(
            "The elements of the attributelist are");
  
        List flowerlist = attributeList.asList();
  
        int ind = 0;
  
        // iterating through the attribute List and
        // printing elements.
        while (ind < flowerlist.size()) {
            System.out.print(flowerlist.get(ind++) + " ");
        }
  
        System.out.println();
  
        // setting value = 6 at key = "hibiscus"
        attributeList.set(5, new Attribute("hibiscus", 6));
  
        System.out.println();
        System.out.println("after setting index 5");
        System.out.println(
            "the elements of the attributelist are");
  
        // iterating through the attribute List and
        // printing elements.
        flowerlist = attributeList.asList();
  
        ind = 0;
        while (ind < flowerlist.size()) {
            System.out.print(flowerlist.get(ind++) + " ");
        }
    }
}

输出

The elements of the attributelist are
rose = 1 sun-flower = 2 tulip = 3 orchid = 4 marie-gold = 5 hibiscus = 0 

after setting index 5
the elements of the attributelist are
rose = 1 sun-flower = 2 tulip = 3 orchid = 4 marie-gold = 5 hibiscus = 6