JAVA 中集合操作

package com.lxj;
import java.util.*;

public class SetTest {
private String colors[]={"orange","tan","orange","white","gray"};
public SetTest(){
ArrayList list;
list=new ArrayList(Arrays.asList(colors));
System.out.println("Array List:"+list);
printNonDuplicate(list);

}
public void printNonDuplicate(Collection collection){
//构建HashSet删除多余的元素
HashSet set=new HashSet(collection);
//将collection放入HashSet后即会消除重复元素
System.out.println("Set: "+set);
       
Iterator iterator=set.iterator();
System.out.println("\nNonDuplicates are");
while(iterator.hasNext()){
System.out.println(iterator.next()+" ");
}
System.out.println();

}
public static void main(String args[]){
new SetTest();
}

}






package com.lxj;
import java.util.Arrays;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

public class ListTest {
public static void baseUse(){
//链表实现
List list=new LinkedList();
list.add("a");//向列表未尾加一下元素a
System.out.println("使用List接口的add()一个参数据方法："+list);
list.add(0, "b");//在指定位置加入b
System.out.println("使用List接口的add()二个参数方法："+list);
list.remove("a");//移除指定元素
System.out.println("使用期List接口的remove()方法删除a: "+list);
}
public static void useSort(){
String[] strArray=new String[]{"z","a","c","C"};
List list=Arrays.asList(strArray);
System.out.println(list);
Collections.sort(list);
System.out.println(list);//根据元素自然顺序排序
Collections.sort(list, String.CASE_INSENSITIVE_ORDER);//根据指定的字母方式排序
System.out.println("指定字母方式："+list);
Collections.sort(list,Collections.reverseOrder());//根据反转自然顺序方式排序
System.out.println("反转自然顺序："+list);
Collections.sort(list, String.CASE_INSENSITIVE_ORDER);
System.out.println(list);
Collections.reverse(list);
System.out.println(list);
}
   public static void main(String args[]){
  // baseUse();
   useSort();
   }
}




package com.lxj;
/*
* 本实例主要是ArrayList类用法
*/
import java.awt.*;
import java.util.*;

public class CollectionTest {
//List是一个能包含重复元素的已排列的Collection，有时list也称为序列,List第一元素下标为0
   
public String colors[]={"red","white","blue"};
public CollectionTest(){
ArrayList list=new ArrayList();//实例化一个arrayList;
list.add(Color.magenta);
for(int i=0;i<colors.length;i++){
list.add(colors[i]);
}
list.add(Color.cyan);
System.out.println("\nArrayList");
for(int i=0;i<list.size();i++)
System.out.println(list.get(i)+" ");
removeString(list);
System.out.println("\n\rArrayList after calling"+"removeString");
for(int i=0;i<list.size();i++){
System.out.println(list.get(i)+" ");
}

}
public void removeString(Collection collection){
Iterator iterator=collection.iterator();
while(iterator.hasNext()){
if(iterator.next() instanceof String){
iterator.remove();
}
}
}
public static void main(String args[]){
new CollectionTest();
}
}





package com.lxj;
import java.util.Set;
import java.util.HashSet;
import java.util.Iterator;

public class TestSet {
public static void main(String args[]){
Set set=new HashSet();
set.add("aaa");
set.add("bbb");
set.add("ccc");
set.add("aaa");
set.add("bbb");
set.add("ccc");
Iterator it=set.iterator();
System.out.println("set size :"+set.size());
while(it.hasNext()){
System.out.println("  "+it.next()+" ");
}

}

}

评论

2 楼 lxj8495138 2008-07-30  

    

1 楼 lxj8495138 2008-07-30  

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