集合框架
为什么使用集合框架
Java集合框架包含的内容
集合框架的接口
List接口的实现类
ArrayList集合类
List接口常用方法
LinkedList集合类
迭代器Iterator
Set&HashSet
HashMap
Collections主要方法
基础例子
MAP TEST
新闻 NEWS
package New; public class lllxxx implements Comparable { private int id; private String title; private String content; private String hh; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getContent() { return content; } public void setContent(String content) { this.content = content; } public String getHh() { return hh; } public void setHh(String hh) { this.hh = hh; } public lllxxx() { super(); // TODO Auto-generated constructor stub } public lllxxx(int id, String title, String content, String hh) { super(); this.id = id; this.title = title; this.content = content; this.hh = hh; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + id; return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; lllxxx other = (lllxxx) obj; if (id != other.id) return false; return true; } @Override public int compareTo(Object obj) { // TODO Auto-generated method stub News news=(News)obj; if(this.id>news.getId()){ return 1; }else if(this.id==news.getId()){ return 0;} else { return -1;} } }
package New; import java.util.HashSet; import java.util.Iterator; import java.util.Set; public class lx { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub lllxxx news=new lllxxx( 4,"体育比赛","斯诺克d","2016-1-1"); lllxxx news1=new lllxxx(1,"体育比赛","斯诺克w","2016-1-1"); lllxxx news2=new lllxxx(3,"体育比3","斯诺克","2016-1-1"); lllxxx news3=new lllxxx(3,"体育比2","斯诺克3","2016-1-1"); Set set=new HashSet(); set.add(news); set.add(news1); set.add(news2); set.add(news3); Iterator it=set.iterator(); while (it.hasNext()) { lllxxx ne=(lllxxx)it.next(); String s=ne.getId()+""; s+=ne.getTitle(); s+=ne.getContent(); s+=ne.getHh(); System.out.println(s); } } }
package New; public class News implements Comparable { private int id; private String title; private String content; private String hh; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getContent() { return content; } public void setContent(String content) { this.content = content; } public String getHh() { return hh; } public void setHh(String hh) { this.hh = hh; } public News(int id, String title, String content, String hh) { super(); this.id = id; this.title = title; this.content = content; this.hh = hh; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + id; result = prime * result + ((title == null) ? 0 : title.hashCode()); return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; News other = (News) obj; if (id != other.id) return false; if (title == null) { if (other.title != null) return false; } else if (!title.equals(other.title)) return false; return true; } public News() { // TODO Auto-generated constructor stub } @Override public int compareTo(Object obj) { // TODO Auto-generated method stub News news=(News)obj; if(this.id>news.getId()){ return 1; }else if(this.id==news.getId()){ return 0;} //+1-1 互换倒序 else { return -1;} } }
package New; import java.util.HashSet; import java.util.Iterator; import java.util.Set; public class SetEntityTest { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub News news=new News( 1,"体育比赛11","斯诺克d","2016-1-1"); News news1=new News(3,"体育比赛44","斯诺克w4","2016-1-1"); News news2=new News(5,"体育比33","斯诺克","2016-1-1"); News news3=new News(3,"体育比44444","斯诺克4444","2016-1-1"); Set set=new HashSet(); set.add(news); set.add(news1); set.add(news2); set.add(news3); Iterator it=set.iterator(); while (it.hasNext()) { News ne=(News)it.next(); String s=ne.getId()+""; s+=ne.getTitle(); s+=ne.getContent(); s+=ne.getHh(); System.out.println(s); } } }
作者:冲天之峰 20160601