Java set of common tools --java

一、ArrayList

Package com.imooc.set; 

Import of java.util.ArrayList;
 Import java.util.List; 

public  class ArrayListDemo { 

    public  static  void main (String [] args) {
         // the name stored with ArrayList programming language, and outputs.
        // names include "Java", "C", "C ++", "Go" and "Swift" 
        List List = new new ArrayList (); 
        list.add ( "the Java" ); 
        list.add ( "C" ); 
        List .add ( "C ++" ); 
        list.add ( "Go" ); 
        list.add ( "Swift" );
         //The number of elements of the list output 
        System.out.println ( "the number of elements in the list:" + list.size ()); 
        
        // iterate all programming languages output 
        System.out.println ( "====== ==================== " );
         for ( int I = 0; I <list.size (); I ++ ) { 
            of System.out.print (List.get (I) + "" ); 
        } 
        System.out.println (); 

        // remove the C ++ list 
        System.out.println ( "================== ======== " );
 //         list.remove (2); 
        list.remove (" C ++ " ); 
        System.out.println ( " after removing the elements of c ++ list is: " );
        for(int i=0;i<list.size();i++) {
            System.out.print(list.get(i)+" ");
        }
        System.out.println();
    }

}

Second, the case

• demand

- Add announcement and display

- Insert the announcement at a specified location

- Delete Announcement

- Modify Announcement

• Notice class properties

- Number id

 - title title

- Created creator

- Created createTime

• Notice class method

-Construction method

- Method get and set property values ​​of

package com.imooc.set;

import java.util.Date;

public class Notice {
    //Notice类，属性：id，title,creator,ctreaterDate
    private int id;
    private String title;
    private String creator;
    private Date creatTime;
    //构造方法
    public Notice(int id, String title, String creator, Date creatTime) {
        super();
        this.id = id;
        this.title = title;
        this.creator = creator;
        this.creatTime = creatTime;
    }
    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 getCreator() {
        return creator;
    }
    public void setCreator(String creator) {
        this.creator = creator;
    }
    public Date getCreatTime() {
        return creatTime;
    }
    public void setCreatTime(Date creatTime) {
        this.creatTime = creatTime;
    }
    
    
    
    
}

Package com.imooc.set; 

Import of java.util.ArrayList;
 Import java.util.Date; 


public  class NoticeTest { 

    public  static  void main (String [] args) {
         // create an object class Notice generates three announcement 
        Notice notice1 = new new Notice (1, "Welcome to the java world!", "administrator", new new a Date ()); 
        Notice Notice2 = new new Notice (2, "please submit the job on time," "teacher," new new a Date ()); 
        notice3 notice = new new notice (. 3, "attendance notice", "teacher", new new a Date ());
        // add announcement 
        ArrayList noticeList =new ArrayList();
        noticeList.add(notice1);
        noticeList.add(notice2);
        noticeList.add(notice3);
        //显示公告
        System.out.println("公告内容为：");
        for(int i=0;i<noticeList.size();i++) {
            System.out.println(i+1+":"+((Notice)noticeList.get(i)).getTitle());
        }
    }

}

3, delete, modify announcement

Package com.imooc.set; 

Import of java.util.ArrayList;
 Import java.util.Date; 


public  class NoticeTest { 
    
    public  static  void main (String [] args) {
         // create an object class Notice generates three announcement 
        Notice notice1 = new new Notice (1, "Welcome to the java world!", "administrator", new new a Date ()); 
        Notice Notice2 = new new Notice (2, "please submit the job on time," "teacher," new new a Date ()); 
        notice3 notice = new new notice (. 3, "attendance notice", "teacher", new new a Date ());
        // add announcement 
        ArrayList noticeList =new new ; () the ArrayList 
        noticeList.add (notice1); 
        noticeList.add (Notice2); 
        noticeList.add (notice3); 
        // display bulletins 
        System.out.println ( "announcement is:" );
         for ( int I = 0 ; I <noticeList.size (); I ++ ) { 
            System.out.println (I + 1'd + ":" + ((Notice) noticeList.get (I)). the getTitle ()); 
        } 
        // then the second Add a location announcement 
        Notice notice4 = new new Notice (4, "online editor can be used", "administrator", new new a Date ()); 
        noticeList.add ( 1 , notice4);
         // display announcement
        System.out.println ( "======================" ); 
        System.out.println ( "announcement is:" );
         for ( int i 0 =; I <noticeList.size (); I ++ ) { 
            System.out.println (I + 1'd + ":" + ((Notice) noticeList.get (I)). the getTitle ()); 
        } 
        // delete time submit a job announcement 
        noticeList.remove (2 );
         // display announcement 
        System.out.println ( "======================" ); 
        System.out .println ( "announcement is:" );
         for ( int I = 0; I <noticeList.size (); I ++  ) {
            the System.out.println(i + 1'd + ":" + . ((Notice) noticeList.get (I)) the getTitle ()); 
        } 
        // modified second announcement title 
        notice4.setTitle ( "the JAVA-line editor You can use the! " ); 
        noticeList.set ( 1 , notice4);
         // display announcement 
        System.out.println (" ====================== " ); 
        System.out.println ( "announcement is:" );
         for ( int I = 0; I <noticeList.size (); I ++ ) { 
            System.out.println (I + 1'd + ":" + (( Notice) noticeList.get (I)) the getTitle ());. 
        } 
    } 

}