如何使用多个线程作为客户端 - 谁都在switch语句中执行任务？我还希望线程执行这些任务，一旦它们执行完就停止（目前这些任务是从用户输入执行的）。
服务器，客户端和开发人员数据库共有3个类，它们包含服务器中ArrayList中“开发人员”对象的构造函数。此数组列表提供了根据特定请求传递给客户端的信息。
这是我的代码：客户：
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.*;
public class QuoteOfTheDayClient_2 {
static String devName;
static String devSkill;
static Boolean devHire;
static Socket echoSocket = null; // holds the Socket object
static Scanner fromServer = null; // input stream from remote host
static Scanner fromServer1 = null; // input stream from remote host
static PrintWriter toServer = null; // output stream to remote host
static PrintWriter toServer1 = null; // output stream to remote host
static Scanner stdIn = new Scanner(System.in);
static String remoteServer = "localhost"; // are you 'local'?!
//String remoteServer = "193.61.190.96"; // remote host is not 'local'!
static int port;
static String reply;// holds reply from remote host
public static void searchForSkill(String skill) {
toServer.println(1);
String quoteNum = "php"; //Search for a specific coding language -
Specific to the entered parameters
System.out.println("Searching for Skill: " + skill + " in Developer
Database");
toServer.println(quoteNum);
while (!(reply = fromServer.nextLine()).isEmpty()) {
// System.out.println(reply1);
System.out.println(reply);// print reply to screen
}
fromServer.nextLine(); // Consume the newline
System.out.println();
}
public static void addDeveloper(String name, String skill,boolean
hire)
{
toServer.println(2);
System.out.println("Add Developer to system ");
stdIn.nextLine(); // flush newline
String quoteString = name;//stdIn.nextLine();
String quoteString1 = skill;//stdIn.nextLine();
boolean quoteString2 = hire;//stdIn.nextLine();
toServer.println(quoteString);
toServer.println(quoteString1);
toServer.println(quoteString2);
fromServer.next();
System.out.println("\nDeveloper entered: " + quoteString + "\n");
while (!(reply = fromServer.nextLine()).isEmpty()) {
// System.out.println(reply1);
System.out.println(reply);// print reply to screen
}
}
public static void checkAvailability(String developerName) {
try {
toServer.println(3);
System.out.println("Send Developer Name to Find Availability:
");
String quoteDel = developerName;
toServer.println(quoteDel);
while (!(reply = fromServer.nextLine()).isEmpty()) {
// System.out.println(reply1);
System.out.println(reply);// print reply to screen
}
} catch (NoSuchElementException e) {
}
}
public static void hireDeveloper(String name) {
toServer.println(4);
String quoteNum = name; //Search for a specific coding language -
Specific to the entered parameters
System.out.println("Searching for: " + name + " in Developer
Database");
toServer.println(quoteNum);
while (!(reply = fromServer.nextLine()).isEmpty()) {
// System.out.println(reply1);
System.out.println(reply);// print reply to screen
}
fromServer.nextLine(); // Consume the newline
System.out.println();
}
public static void printAllDevelopers(){
toServer.println(5);
while (!(reply = fromServer.nextLine()).isEmpty()) {
// System.out.println(reply1);
System.out.println(reply);// print reply to screen
}
fromServer.nextLine(); // Consume the newline
System.out.println();
}
public static void clientMenu(){
try {
port = 4444; // 17 for localhost
echoSocket = new Socket(remoteServer, port);
fromServer = new Scanner(echoSocket.getInputStream());
fromServer1 = new Scanner(echoSocket.getInputStream());
toServer = new PrintWriter(echoSocket.getOutputStream(), true);
toServer1 = new PrintWriter(echoSocket.getOutputStream(),
true);
OutputStream os = echoSocket.getOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(os);
} catch (Exception e) {
System.err.println("Exception: " + e);
System.exit(1);
} // try-catch
String reply;// holds reply from remote host
int command;
String reply1;
String devName="David Blaine";
String devSkill="Java";
System.out.println("Enter command: 1:Search Skill 2:Add
Developer 3:Search Availability 4:Hire Developer 5:Show all
Developers 6:Exit");
command = 0;
command = command+1;
// while (command != 0) {
for(int i=1;i<6;i++) {
command=i;
switch (i) {
case 1: {
// get quote
searchForSkill("PHP");
break;
}
case 2: {
// add quote
addDeveloper("David Blaine", "Java", true);
break;
}
case 3: {
// delete quote
checkAvailability("David Ferguson");
break;
}
case 4: {
hireDeveloper("Thompson");
break;
}
case 5: {
printAllDevelopers();
}
case 6: {
System.exit(6);
}
default:
System.out.println("*** Command not recognised ***");
break;
}
System.out.println("Enter command: 1:Search Skill 2:Add Developer
3:Search Availability 4:Hire Developer 5:Show all Developers
6:Exit");
command = stdIn.nextInt();
//}
}
toServer.println(command);
try {
echoSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
fromServer.close();
toServer.close();
stdIn.close();
}
public static void main(String[] args) throws IOException {
clientMenu();
} // main
} // EchoClient
服务器代码：
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.PrintWriter;
import java.lang.reflect.Array;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.InputMismatchException;
import java.util.List;
import java.util.Scanner;
public class QuoteOfTheDayServer_2 {
private static DeveloperDatabase[] developerList = new
DeveloperDatabase[7];
static DeveloperDatabase temp []=new DeveloperDatabase[7];
static String userAddDevName;
static String userAddCodeSkills;
static Boolean userAddHireAvailability;
static int command;
static List<DeveloperDatabase> list = new
ArrayList<DeveloperDatabase>(){
{
add(new DeveloperDatabase(1,"David Ferguson", "Java",
true));
add(new DeveloperDatabase(2,"Grant Thompson", "Java",
true));
add(new DeveloperDatabase(3,"Craig Jackson", "C++", true));
add(new DeveloperDatabase(4,"Kevin James","C++", true));
add(new DeveloperDatabase(5,"Greg Troupe", "Python",
true));
add(new DeveloperDatabase(6,"James Smith", "Python",
true));
add(new DeveloperDatabase(7,"Jamie Richie", "PHP", true));
add(new DeveloperDatabase(8,"Rory McGrattan", "PHP",
false));
}
};
public static String printJava(){
String message="";
for (int i=0;i<2;i++){
message +=list.get(i).toString();
message+=" \n";
}
return message;
}
public static String printC(){
String message="";
for (int i=2;i<4;i++){
message +=list.get(i).toString();
message+=" \n";
}
return message;
}
public static String printPy(){
String message="";
for (int i=4;i<6;i++){
message +=list.get(i).toString();
message+=" \n";
}
return message;
}
public static String printPHP(){
String message="";
for (int i=6;i<8;i++){
message +=list.get(i).toString();
message+=" \n";
}
return message;
}
public static void addDeveloper(String name,String
codeSkill,Boolean hire){
userAddDevName=name;
userAddCodeSkills = codeSkill;
userAddHireAvailability = hire;
System.out.println("*********Adding Developer***********");
System.out.println(userAddDevName+ " has been added to the
system");
list.add(new DeveloperDatabase(9,
userAddDevName,userAddCodeSkills, userAddHireAvailability));
System.out.println(list.get(8));
}//addDeveloper
public static String checkAvail(String clientMessage){
String message="";
for (int i=0;i<list.size();i++){
if
(clientMessage.equalsIgnoreCase(list.get(i).getDeveloperName())) {
message+= list.get(i).toString();
message+="\n";
}
} return message;
}
public static String printAllDevelopers(){
String message="";
for (int i=0;i<8;i++){
message +=list.get(i).toString();
message+=" \n";
}
return message;
}
public static void main(String[] args) throws IOException {
// Wrap the standard System.in stream with a Scanner so that
Scanner stdIn = new Scanner(System.in);
Scanner fromClient = null;
PrintWriter toClient = null;
PrintWriter toClient1=null;
int pNum = 4444;
ServerSocket sSocket = null;
Socket cSocket = null;
try {
sSocket = new ServerSocket(pNum);
} catch (IOException e) {
System.out.println("Couldn't listen on port: " + pNum + ";
" +
e);
System.exit(1);
}
// Continuously wait for client; accept them; and send a quote
to
them.
while (true) {
try {
System.out.println("Waiting for client ....");
// Blocking 'accept' i.e. wait for a client
cSocket = sSocket.accept();
System.out.println("Client connected from: " +
cSocket.getInetAddress());
// Set up the output stream for the server, i.e. a
PrintWriter stream
toClient = new PrintWriter(cSocket.getOutputStream(),
true);
toClient1 = new PrintWriter(cSocket.getOutputStream(),
true);
ObjectInputStream ois = new
ObjectInputStream(cSocket.getInputStream());
fromClient = new Scanner(cSocket.getInputStream());
try {
command = fromClient.nextInt();
//fromClient.nextLine();
} catch (InputMismatchException e){
System.out.print("Your selection can only be an
integer!");
}
System.out.println("Received command: " + command + "
from
client at " + cSocket.getInetAddress());
while (command != 0) {
switch (command) {
case 1: // get skills
{
System.out.println("GET skill");
fromClient.nextLine();
String quoteNum =
fromClient.nextLine();//receive from client
if (quoteNum.equalsIgnoreCase("Java")) {
toClient1.println(printJava());
} else if
(quoteNum.equalsIgnoreCase("C++")) {
toClient1.println(printC());
} else if
(quoteNum.equalsIgnoreCase("Python"))
{
toClient.println(printPy());
} else if
(quoteNum.equalsIgnoreCase("PHP")) {
toClient.println(printPHP());
}
else {
toClient.println("No developer with
those
skills found");
}
//
toClient.println(list.equals("Java"));//number -1 for array (0) to
client print
System.out.println("Pushed Developer
number: "
+ quoteNum + " to client at " + cSocket.getInetAddress());
//toClient.println(quotes[quoteNum]); //
return
quote //if "java' { get(0) get(1)
break;
}
case 2: // add quote
{
System.out.println("ADD Developer to
System");
fromClient.nextLine(); // flush newline
String quote = fromClient.next();
fromClient.nextLine();
String quote1 = fromClient.next();
fromClient.nextLine();
boolean quote2 = fromClient.nextBoolean();
toClient.println("The\t*************Developer
has been Added to the Developer Database********");
list.add(new DeveloperDatabase(9, quote,
quote1, quote2));
toClient.println(list.get(8).toString());
//addDeveloper(quote,quote1,quote2);
System.out.println(list.get(8));
//System.out.println("Received quote from
client:" + quote);
quote = quote + "\n\n";
//list.add((quote);
System.out.println("Added Developer: " +
quote);
break;
}
case 3: // Check if Developer is available
{
System.out.println("Check if developer is
Available\n");
fromClient.nextLine();
String quoteNum = fromClient.nextLine();
System.out.println("Checking availability
for:
" + quoteNum);
if (quoteNum.equalsIgnoreCase("Rory
McGrattan")) {
toClient.println("The Developer is not
available for hire");
} else {
toClient.println("The Developer is
available for hire");
}break;
}case 4: {
System.out.println("Hire A Developer");
String quoteNum =fromClient.next();
System.out.println("Client wants to hire:
"+quoteNum);
String message = quoteNum;
for(int i=0;i<list.size();i++){
if
(quoteNum.equalsIgnoreCase(list.get(i).getDeveloperName())){
list.get(i).hireDeveloper();
}//if
}//if
//System.out.println(message);
toClient.println("******* You have Hired:
"+
message+" ********");
break;
}
case 5: {// Print all Developers
String message="";
for (int i=0;i<8;i++){
message +=list.get(i).toString();
message+=" \n";
}
toClient.println(message);
}
default:
break;
}
try {
//command = fromClient.nextInt();
}catch(InputMismatchException e){
}
System.out.println("Received command: " + command +
"from client at " + cSocket.getInetAddress());
}
// Close all streams
toClient.close();
cSocket.close();
fromClient.close();
stdIn.close();
} catch (IOException e) {
System.out.println("Accept failed: " + pNum + "; " +
e);
System.exit(1);
}
}
} // main
} // QuoteOfTheDayServer_2
DeveloperDatabase代码：
public class DeveloperDatabase {
private int id;
private String developerName;
private String codingLanguage;
private boolean freeForHire;
public DeveloperDatabase(){
}
public DeveloperDatabase(int id,String name,String codeSkills,boolean
hire){
this.id = id;
this.developerName = name;
this.codingLanguage=codeSkills;
this.freeForHire=hire;
}
public String toString() {
String message = "\tName: " +developerName;
message += "\n" + "\tCoding Language: "+ codingLanguage+"\n";
if (freeForHire== true) {
message += "\tThe developer is Available! for Hire!\n";
} else {
message += "\tThe developer is not Available for Hire!\n";
}
return message;
}//toString
public boolean getFreeForHire() {
if (freeForHire==true){
System.out.println("The Developer is free to hire!");
}else{
System.out.println("The Developer is not free to hire!");
}
return freeForHire;
}
public String getCodingLanguage() {
return codingLanguage;
}
public void hireDeveloper(){
if (freeForHire==true)
freeForHire = false;
System.out.println(developerName +" is Hired!");
}
public String getDeveloperName() {
return developerName;
}
public static void main(String[] args) {
}//main
}//class
答案 0 :(得分：0)
1）
ExecutorService service=Executors.newFixedThreadPool(5);
2） //将（在命令！= 0）中移动代码insde替换为实现runnable的单独类，让我们调用此任务。
public class Task实现了Runnable {
private final Integer command;
public Task(Integer command) {
this.command=command;
}
@Override
public void run() {
//do something, like switch statement
}
}
3）创建一个辅助方法，并调用此方法
public void process(Task t){
service.submit(t);
}