e354. creating a set that retains order-of-insertion.txt

这里面包含了一百多个JAVA源文件

Set set = new LinkedHashSet();
    
    // Add some elements
    set.add("1");
    set.add("2");
    set.add("3");
    set.add("2");
    
    // List the elements
    for (Iterator it=set.iterator(); it.hasNext(); ) {
        Object o = it.next();
    }
    // [1, 2, 3]