Question

麻烦对下面的java代码进行每段注释，关键有用的语句给点中文注释说明，这是个聊天室程序的一部分，详见下

聊天信息的持久化类：
package com.test.bean;
// default package
import java.sql.Timestamp;
/**
* Mess entity. @author MyEclipse Persistence Tools
*/public class Mess implements java.io.Serializable {

// Fields
private Integer messageId;
private String roomName;
private String sendName;
private String context;
private Timestamp messDate;
// Constructors
/** default constructor */
public Mess() { }
/** minimal constructor */
public Mess(Timestamp messdate) {this.messDate = messdate; }
/** full constructor */
public Mess(String roomName, String sendName, String context, Timestamp messdate) {
this.roomName = roomName;
this.sendName = sendName;
this.context = context;
this.messDate = messdate;
}
// Property accessors
public Integer getMessageId() {
return this.messageId;
}
public void setMessageId(Integer messageId) { this.messageId = messageId; }
public String getRoomName() { return this.roomName;
}
public void setRoomName(String roomName) {
this.roomName = roomName;
}

public String getSendName() { return this.sendName; }
public void setSendName(String sendName) {this.sendName = sendName; }
public String getContext() {return this.context;}
public void setContext(String context) {this.context = context;}
public Timestamp getMessDate() {
return messDate;
}

public void setMessDate(Timestamp messDate) {this.messDate = messDate; }

Answer 1

首先，我想说，这个类其实什么都没干，就是定义了一些变量和这样变量相应的set。get方法，当然还有这个类的构造函数。以下是解释：
package com.test.bean; //说明你的类所在的包
// default package
import java.sql.Timestamp; //导入所需要的类。
/**
* Mess entity. @author MyEclipse Persistence Tools //注释。不用管
*/
public class Mess implements java.io.Serializable {//定义类，实现了java.io.Serializable 接口

// 以下5句定义了5个私有变量
private Integer messageId;
private String roomName;
private String sendName;
private String context;
private Timestamp messDate;
// Constructors
/** default constructor */
//以下是构造函数，就是所有Mess（）函数，函数有几个，但参数不一样，这个是函数的重载。
public Mess() { }
/** minimal constructor */
public Mess(Timestamp messdate) {this.messDate = messdate; }
/** full constructor */
public Mess(String roomName, String sendName, String context, Timestamp messdate) {
this.roomName = roomName;
this.sendName = sendName;
this.context = context;
this.messDate = messdate;
}
// Property accessors
//以下是上面定义的变量的set和get方法，java给类里的变量赋值和得到类里的变量值都是用get，set方法的。
public Integer getMessageId() {
return this.messageId;
}
public void setMessageId(Integer messageId) { this.messageId = messageId; }
public String getRoomName() { return this.roomName;
}
public void setRoomName(String roomName) {
this.roomName = roomName;
}

public String getSendName() { return this.sendName; }
public void setSendName(String sendName) {this.sendName = sendName; }
public String getContext() {return this.context;}
public void setContext(String context) {this.context = context;}
public Timestamp getMessDate() {
return messDate;
}

public void setMessDate(Timestamp messDate) {this.messDate = messDate; }
然后就没了。。。真的里面什么内容都没有，就是构造函数重载了，需要看看，下面的set，get方法直接无视，eclipse都可以自动生成。

Answer 2

package com.test.bean;
// default package
import java.sql.Timestamp;
/**
* Mess entity. @author MyEclipse Persistence Tools
*/public class Mess implements java.io.Serializable {

// Fields //各种字段。下边四个类似于消息id，房间名，发送名，时间戳
private Integer messageId;
private String roomName;
private String sendName;
private String context;
private Timestamp messDate;
// Constructors
/** default constructor */
public Mess() { }//无参构造函数
/** minimal constructor */
public Mess(Timestamp messdate) {this.messDate = messdate; }//有参构造函数
/** full constructor */
public Mess(String roomName, String sendName, String context, Timestamp messdate) {//重载的有参构造函数
this.roomName = roomName;
this.sendName = sendName;
this.context = context;
this.messDate = messdate;
}
// Property accessors//一下是对4个字段的封装
public Integer getMessageId() {
return this.messageId;
}
public void setMessageId(Integer messageId) { this.messageId = messageId; }
public String getRoomName() { return this.roomName;
}
public void setRoomName(String roomName) {
this.roomName = roomName;
}

public String getSendName() { return this.sendName; }
public void setSendName(String sendName) {this.sendName = sendName; }
public String getContext() {return this.context;}
public void setContext(String context) {this.context = context;}
public Timestamp getMessDate() {
return messDate;
}

public void setMessDate(Timestamp messDate) {this.messDate = messDate; }

Answer 3

这个就是存储一些数据（messageId，roomName，sendName，context，messDate），存储的时候就要先设置，然后再获取吧，因此就有一大堆的set（设置函数）和一堆的get（获取值函数）。
另外该类实现了java.io.Serializable 接口，是为了传递。

Answer 4

楼主还说多看看java基础，这些都是很基础的东西