写在前面：
上一篇记录了Socket聊天程序的客户端设计，为了记录的完整性，这里还是将Socket聊天的最后一个模块——Common模块记录一下。Common的设计如下：
功能说明：
Common模块主要是数据交互，这里使用JSON数据进行交互，common模块定义了各类交互信息，SendHelper实现的socket信息的传送，I18N是语言话，ConstantValue是系统中的配置以及常量（这里常量都是用接口，这个可能不太好），对于ReturnMessage拥有一系列的DTO作为其content属性。
具体实现：
[SendHelper.java]
SendHelper负责发送socket数据，不管是服务端还是客户端，都由SendHelper来发送数据，SendHelper的具体实现如下：
public class SendHelper {
private SendHelper() {
}
public synchronized static void send(Socket socket, BaseMessage message) {
if (socket != null && !socket.isClosed()) {
try {
PrintWriter out = new PrintWriter(socket.getOutputStream());
LoggerUtil.trach(" [" + JSON.toJSON(message) + "] SEND AT " + new Date());
out.println(JSON.toJSON(message));
out.flush(); // ??
Thread.sleep(ConstantValue.MESSAGE_PERIOD);
} catch (Exception ignore) {
LoggerUtil.debug("Message send faild !" + ignore.getMessage(), ignore);
}
}
}
public synchronized static void upload(Socket socket, File file) {
if (socket != null && !socket.isClosed()) {
InputStream is = null;
try {
OutputStream os = socket.getOutputStream();
is = new FileInputStream(file);
byte[] buff = new byte[ConstantValue.BUFF_SIZE];
int len = -1;
while ((len = is.read(buff)) != -1) {
os.write(buff, 0, len);
}
os.flush();
Thread.sleep(ConstantValue.MESSAGE_PERIOD);
} catch (Exception ignore) {
LoggerUtil.debug("File upload faild !" + ignore.getMessage(), ignore);
} finally {
if (is != null) {
try {
is.close();
} catch (Exception ignore) {
}
is = null;
}
}
}
}
}
[BaseMessage.java...]
这里使用JSON数据进行交互，所有的消息数据传输对象对应的类都继承BaseMessage，BaseMessage的设计以及其他Message的设计如下（这里为了缩小篇幅，将其他Messaged类的代码收起来）：
/**
* BaseMessage
* @author yaolin
*
*/
public class BaseMessage { protected String from;
protected String to;
protected String owner;
protected int type; public String getFrom() {
return from;
}
public BaseMessage setFrom(String from) {
this.from = from; // which tab will be select
return this;
}
public String getTo() {
return to;
}
public BaseMessage setTo(String to) {
this.to = to;
return this;
}
public String getOwner() {
return owner;
}
public BaseMessage setOwner(String owner) {
this.owner = owner; // display
return this;
}
public int getType() {
return type;
}
public BaseMessage setType(int type) {
this.type = type;
return this;
} }
public class AliveMessage extends BaseMessage {
private final int type = MessageType.ALIVE;
public int getType() {
return type;
}
}
public class ChatMessage extends BaseMessage {
private final int type = MessageType.CHAT;
private String content;
public int getType() {
return type;
}
public String getContent() {
return content;
}
public ChatMessage setContent(String content) {
this.content = content;
return this;
}
}
public class FileMessage extends BaseMessage {
private final int type = MessageType.FILE;
private String name;
private long size;
private String ext;
public String getName() {
return name;
}
public FileMessage setName(String name) {
this.name = name;
return this;
}
public long getSize() {
return size;
}
public FileMessage setSize(long size) {
this.size = size;
return this;
}
public String getExt() {
return ext;
}
public FileMessage setExt(String ext) {
this.ext = ext;
return this;
}
public int getType() {
return type;
}
}
public class LoginMessage extends BaseMessage{
private final int type = MessageType.LOGIN;
private String username;
private String password;
public int getType() {
return type;
}
public String getUsername() {
return username;
}
public LoginMessage setUsername(String username) {
this.username = username;
return this;
}
public String getPassword() {
return password;
}
public LoginMessage setPassword(String password) {
this.password = password;
return this;
}
}
public class LogoutMessage extends BaseMessage {
private final int type = MessageType.LOGOUT;
private String username;
public String getUsername() {
return username;
}
public LogoutMessage setUsername(String username) {
this.username = username;
return this;
}
public int getType() {
return type;
}
}
public class RegisterMessage extends BaseMessage{
private final int type = MessageType.REGISTER;
private String username;
private String password;
private String confirm;
public String getUsername() {
return username;
}
public RegisterMessage setUsername(String username) {
this.username = username;
return this;
}
public String getPassword() {
return password;
}
public RegisterMessage setPassword(String password) {
this.password = password;
return this;
}
public String getConfirm() {
return confirm;
}
public RegisterMessage setConfirm(String confirm) {
this.confirm = confirm;
return this;
}
public int getType() {
return type;
}
}
public class ReturnMessage extends BaseMessage {
private final int type = MessageType.RETURN;
private boolean success;
// success
private String key;
private Object content;
// error
private String message;
private String code;
public int getType() {
return type;
}
public boolean isSuccess() {
return success;
}
public ReturnMessage setSuccess(boolean success) {
this.success = success;
return this;
}
public String getKey() {
return key;
}
public ReturnMessage setKey(String key) {
this.key = key;
return this;
}
public Object getContent() {
return content;
}
public ReturnMessage setContent(Object content) {
this.content = content;
return this;
}
public String getMessage() {
return message;
}
public ReturnMessage setMessage(String message) {
this.message = message;
return this;
}
public String getCode() {
return code;
}
public ReturnMessage setCode(String code) {
this.code = code;
return this;
}
}
对于ReturnMessage，其他Content属性可以是各种DTO，目前有两个，由KEY指定是那种DTO：
public interface Key {
/**
* 登陆
*/
String LOGIN = "LOGIN";
/**
* 注册
*/
String REGISTER = "REGISTER";
/**
* Client 上线 / 离线 通知
*/
String NOTIFY = "NOTIFY";
/**
* 拉去在线 Client 列表
*/
String LISTUSER = "LISTUSER";
/**
* TIP 提示
*/
String TIP = "TIP";
}
public class ClientListUserDTO {
private Set<String> listUser;
public Set<String> getListUser() {
return listUser;
}
public void setListUser(Set<String> listUser) {
this.listUser = listUser;
}
}
public class ClientNotifyDTO {
private boolean flag; // true:online,false:offline
private String username; // hostname
public ClientNotifyDTO() {
}
public ClientNotifyDTO(boolean flag, String username) {
this.flag = flag;
this.username = username;
}
public boolean isFlag() {
return flag;
}
public void setFlag(boolean flag) {
this.flag = flag;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
}
另外几个常量也给出：
public interface ConstantValue {
/**
* 缓冲区大小
*/
int BUFF_SIZE = 1024;
/**
* 调试模式
*/
int DEBUG_LEVEL = 0;
/**
* 客户端接收文件的存储路径
*/
String CLIENT_RECEIVE_DIR = "./file";
/**
* KEEPALIVE PERIOD'second
*/
int KEEP_ALIVE_PERIOD = 20;
/**
* 最大socket线程处理数
*/
int MAX_POOL_SIZE = PropertiesUtil.getInt("server-thread-pool-size", 30);
/**
* <pre>
* 检测是否有新的数据时间间隔'ms
* (server.SocketDispatch,client.ReceiveListener,SendHelper)
* 使用同一个Thread.sleep时间保证数据能正确接收到，同时降低CPU的使用率
* !!!!! -非常重要- !!!!!
* </pre>
*/
int MESSAGE_PERIOD = 500;
/**
* 服务器IP地址
*/
String SERVER_IP = PropertiesUtil.get("server-ip", "127.0.0.1");
/**
* 服务器名称，用户注册不能使用此用户名
*/
String SERVER_NAME = "niloay";
/**
* 服务器端口
*/
int SERVER_PORT = PropertiesUtil.getInt("server-port", 8888);
/**
* SOCKET超时时间'second
*/
int TIME_OUT = 120;
/**
* 群发标识TO:ALL,用户注册不能使用此用户名
*/
String TO_ALL = "TO_ALL";
}
public interface I18N {
//---------------------------------
// TEXT
//---------------------------------
/**
* APP_NAME
*/
String TEXT_APP_NAME = "NILOAY-CHAT v1.0.0";
/**
* 登陆
*/
String TEXT_LOGIN = "登陆";
/**
* 注册
*/
String TEXT_REGISTER = "注册";
/**
* 账号
*/
String TEXT_USERNAME = "账号";
/**
* 密码
*/
String TEXT_PASSWORD = "密码";
//---------------------------------
// BTN
//---------------------------------
/**
* 注册
*/
String BTN_REGISTER = "注册";
/**
* 登陆
*/
String BTN_LOGIN = "登陆";
/**
* 退出
*/
String BTN_EXIT = "退出";
/**
* 发送
*/
String BTN_SEND = "发送";
/**
* 发送文件
*/
String BTN_SEND_FILE = "发送文件";
//---------------------------------
// INFO
//---------------------------------
/**
* 请填写注册账号和密码
*/
String INFO_REGISTER_EMPTY_DATA = "请填写注册账号和密码";
/**
* 用户已存在
*/
String INFO_REGISTER_CLIENT_EXIST = "用户已存在";
/**
* 注册成功
*/
String INFO_REGISTER_OK = "注册成功";
/**
* 请输入登陆账号和密码
*/
String INFO_LOGIN_EMPTY_DATA = "请输入登陆账号和密码";
/**
* 登陆账号或密码错误
*/
String INFO_LOGIN_ERROR_DATA = "登陆账号或密码错误";
/**
* 暂不支持文件群发
*/
String INFO_FILE_TO_ALL_ERROR = "暂不支持文件群发";
/**
* 文件发送成功
*/
String INFO_FILE_SEND_SUCCESSFULLY = "文件发送成功";
/**
* 文件接收成功
*/
String INFO_FILE_RECEIVE_SUCCESSFULLY = "文件接收成功";
}
关于socket聊天程序的实现，详见：