商品名称遍历，某商品管理系统的商品名称存储在一个字符串数组中，现需要自定义一个双向迭代器，实现对该商品数组的（前向和后向）遍历，请用字符绘制类图，并java代码实现编程

以下是该问题的类图和Java代码实现：

类图：

+---------------------------+
|     商品名称遍历器接口      |
+---------------------------+
| +hasNext():boolean        |
| +next():String            |
| +hasPrevious():boolean    |
| +previous():String        |
+---------------------------+

+---------------------------+
|     商品名称数组类         |
+---------------------------+
| -names:String[]           |
+---------------------------+
| +iterator():Iterator      |
+---------------------------+

+---------------------------+
|     商品名称双向迭代器类    |
+---------------------------+
| -names:String[]           |
| -current:int              |
+---------------------------+
| +hasNext():boolean        |
| +next():String            |
| +hasPrevious():boolean    |
| +previous():String        |
+---------------------------+

Java代码实现：

import java.util.Iterator;

public interface NameIterator {
    boolean hasNext();
    String next();
    boolean hasPrevious();
    String previous();
}

public class NameArray {
    private String[] names;
    
    public NameArray(String[] names) {
        this.names = names;
    }
    
    public Iterator iterator() {
        return new NameIteratorImpl();
    }
    
    private class NameIteratorImpl implements NameIterator {
        private int current = 0;
        
        public boolean hasNext() {
            return current < names.length;
        }
        
        public String next() {
            String name = names[current];
            current++;
            return name;
        }
        
        public boolean hasPrevious() {
            return current > 0;
        }
        
        public String previous() {
            current--;
            String name = names[current];
            return name;
        }
    }
}

public static void main(String[] args) {
    String[] names = {"apple", "banana", "orange", "pear"};
    NameArray nameArray = new NameArray(names);
    NameIterator iterator = nameArray.iterator();
    
    while (iterator.hasNext()) {
        System.out.println(iterator.next());
    }
    
    while (iterator.hasPrevious()) {
        System.out.println(iterator.previous());
    }
}