JAVA设计说明书怎么写

Java程式包括：应用程序、游戏、电子书等等！Java是Sun公司推出的一种编程语言。它是一种通过解释方式来执行的语言，语法规则和C类似。同时，Java也是一种跨平台的程序设计语言。用Java语言编写的程序叫做“Applet”(小应用程序)，用编译器将它编译成类文件后，将它存在>

java hello world其实很简单，有一个main函数作为程序的入口，有一个输出语句就ok了。

但是要注意：文件名必须要与类名一致

例如如下代码：HelloWorldjava 文件

public class HelloWorld{
    public static void main(Sring[] args){
    Systemoutprintln("Hello World");
    }
}

package comweixinutil;

import javaioFile;
import javaioFileOutputStream;
import javaioIOException;
import javaioInputStream;
import javaioOutputStream;
import javaioPrintWriter;
import javaioRandomAccessFile;

import orgapachecommonsnetPrintCommandListener;
import orgapachecommonsnetftpFTP;
import orgapachecommonsnetftpFTPClient;
import orgapachecommonsnetftpFTPFile;
import orgapachecommonsnetftpFTPReply;

import comweixinconstantDownloadStatus;
import comweixinconstantUploadStatus;

/
支持断点续传的FTP实用类
@version 01 实现基本断点上传下载
@version 02 实现上传下载进度汇报
@version 03 实现中文目录创建及中文文件创建，添加对于中文的支持
/
public class ContinueFTP {
public FTPClient ftpClient = new FTPClient();

public ContinueFTP(){
//设置将过程中使用到的命令输出到控制台
thisftpClientaddProtocolCommandListener(new PrintCommandListener(new PrintWriter(Systemout)));
}

/
连接到FTP服务器
@param hostname 主机名
@param port 端口
@param username 用户名
@param password 密码
@return 是否连接成功
@throws IOException
/
public boolean connect(String hostname,int port,String username,String password) throws IOException{
ftpClientconnect(hostname, port);
ftpClientsetControlEncoding("GBK");
if(FTPReplyisPositiveCompletion(ftpClientgetReplyCode())){
if(ftpClientlogin(username, password)){
return true;
}
}
disconnect();
return false;
}

/
从FTP服务器上下载文件,支持断点续传，上传百分比汇报
@param remote 远程文件路径
@param local 本地文件路径
@return 上传的状态
@throws IOException
/
public DownloadStatus download(String remote,String local) throws IOException{
//设置被动模式
ftpCliententerLocalPassiveMode();
//设置以二进制方式传输
ftpClientsetFileType(FTPBINARY_FILE_TYPE);
DownloadStatus result;

//检查远程文件是否存在
FTPFile[] files = ftpClientlistFiles(new String(remotegetBytes("GBK"),"iso-8859-1"));
if(fileslength != 1){
Systemoutprintln("远程文件不存在");
return DownloadStatusRemote_File_Noexist;
}

long lRemoteSize = files[0]getSize();
File f = new File(local);
//本地存在文件，进行断点下载
if(fexists()){
long localSize = flength();
//判断本地文件大小是否大于远程文件大小
if(localSize >= lRemoteSize){
Systemoutprintln("本地文件大于远程文件，下载中止");
return DownloadStatusLocal_Bigger_Remote;
}

//进行断点续传，并记录状态
FileOutputStream out = new FileOutputStream(f,true);
ftpClientsetRestartOffset(localSize);
InputStream in = ftpClientretrieveFileStream(new String(remotegetBytes("GBK"),"iso-8859-1"));
byte[] bytes = new byte[1024];
long step = lRemoteSize /100;
long process=localSize /step;
int c;
while((c = inread(bytes))!= -1){
outwrite(bytes,0,c);
localSize+=c;
long nowProcess = localSize /step;
if(nowProcess > process){
process = nowProcess;
if(process % 10 == 0)
Systemoutprintln("下载进度："+process);
//TODO 更新文件下载进度,值存放在process变量中
}
}
inclose();
outclose();
boolean isDo = ftpClientcompletePendingCommand();
if(isDo){
result = DownloadStatusDownload_From_Break_Success;
}else {
result = DownloadStatusDownload_From_Break_Failed;
}
}else {
OutputStream out = new FileOutputStream(f);
InputStream in= ftpClientretrieveFileStream(new String(remotegetBytes("GBK"),"iso-8859-1"));
byte[] bytes = new byte[1024];
long step = lRemoteSize /100;
long process=0;
long localSize = 0L;
int c;
while((c = inread(bytes))!= -1){
outwrite(bytes, 0, c);
localSize+=c;
long nowProcess = localSize /step;
if(nowProcess > process){
process = nowProcess;
if(process % 10 == 0)
Systemoutprintln("下载进度："+process);
//TODO 更新文件下载进度,值存放在process变量中
}
}
inclose();
outclose();
boolean upNewStatus = ftpClientcompletePendingCommand();
if(upNewStatus){
result = DownloadStatusDownload_New_Success;
}else {
result = DownloadStatusDownload_New_Failed;
}
}
return result;
}

/
上传文件到FTP服务器，支持断点续传
@param local 本地文件名称，绝对路径
@param remote 远程文件路径，使用/home/directory1/subdirectory/fileext 按照Linux上的路径指定方式，支持多级目录嵌套，支持递归创建不存在的目录结构
@return 上传结果
@throws IOException
/
public UploadStatus upload(String local,String remote) throws IOException{
//设置PassiveMode传输
ftpCliententerLocalPassiveMode();
//设置以二进制流的方式传输
ftpClientsetFileType(FTPBINARY_FILE_TYPE);
ftpClientsetControlEncoding("GBK");
UploadStatus result;
//对远程目录的处理
String remoteFileName = remote;
if(remotecontains("/")){
remoteFileName = remotesubstring(remotelastIndexOf("/")+1);
//创建服务器远程目录结构，创建失败直接返回
if(CreateDirecroty(remote, ftpClient)==UploadStatusCreate_Directory_Fail){
return UploadStatusCreate_Directory_Fail;
}
}

//检查远程是否存在文件
FTPFile[] files = ftpClientlistFiles(new String(remoteFileNamegetBytes("GBK"),"iso-8859-1"));
if(fileslength == 1){
long remoteSize = files[0]getSize();
File f = new File(local);
long localSize = flength();
if(remoteSize==localSize){
return UploadStatusFile_Exits;
}else if(remoteSize > localSize){
return UploadStatusRemote_Bigger_Local;
}

//尝试移动文件内读取指针,实现断点续传
result = uploadFile(remoteFileName, f, ftpClient, remoteSize);

//如果断点续传没有成功，则删除服务器上文件，重新上传
if(result == UploadStatusUpload_From_Break_Failed){
if(!ftpClientdeleteFile(remoteFileName)){
return UploadStatusDelete_Remote_Faild;
}
result = uploadFile(remoteFileName, f, ftpClient, 0);
}
}else {
result = uploadFile(remoteFileName, new File(local), ftpClient, 0);
}
return result;
}
/
断开与远程服务器的连接
@throws IOException
/
public void disconnect() throws IOException{
if(ftpClientisConnected()){
ftpClientdisconnect();
}
}

/
递归创建远程服务器目录
@param remote 远程服务器文件绝对路径
@param ftpClient FTPClient对象
@return 目录创建是否成功
@throws IOException
/
public UploadStatus CreateDirecroty(String remote,FTPClient ftpClient) throws IOException{
UploadStatus status = UploadStatusCreate_Directory_Success;
String directory = remotesubstring(0,remotelastIndexOf("/")+1);
if(!directoryequalsIgnoreCase("/")&&!ftpClientchangeWorkingDirectory(new String(directorygetBytes("GBK"),"iso-8859-1"))){
//如果远程目录不存在，则递归创建远程服务器目录
int start=0;
int end = 0;
if(directorystartsWith("/")){
start = 1;
}else{
start = 0;
}
end = directoryindexOf("/",start);
while(true){
String subDirectory = new String(remotesubstring(start,end)getBytes("GBK"),"iso-8859-1");
if(!ftpClientchangeWorkingDirectory(subDirectory)){
if(ftpClientmakeDirectory(subDirectory)){
ftpClientchangeWorkingDirectory(subDirectory);
}else {
Systemoutprintln("创建目录失败");
return UploadStatusCreate_Directory_Fail;
}
}

start = end + 1;
end = directoryindexOf("/",start);

//检查所有目录是否创建完毕
if(end <= start){
break;
}
}
}
return status;
}

/
上传文件到服务器,新上传和断点续传
@param remoteFile 远程文件名，在上传之前已经将服务器工作目录做了改变
@param localFile 本地文件File句柄，绝对路径
@param processStep 需要显示的处理进度步进值
@param ftpClient FTPClient引用
@return
@throws IOException
/
public UploadStatus uploadFile(String remoteFile,File localFile,FTPClient ftpClient,long remoteSize) throws IOException{
UploadStatus status;
//显示进度的上传
long step = localFilelength() / 100;
long process = 0;
long localreadbytes = 0L;
RandomAccessFile raf = new RandomAccessFile(localFile,"r");
OutputStream out = ftpClientappendFileStream(new String(remoteFilegetBytes("GBK"),"iso-8859-1"));
//断点续传
if(remoteSize>0){
ftpClientsetRestartOffset(remoteSize);
process = remoteSize /step;
rafseek(remoteSize);
localreadbytes = remoteSize;
}
byte[] bytes = new byte[1024];
int c;
while((c = rafread(bytes))!= -1){
outwrite(bytes,0,c);
localreadbytes+=c;
if(localreadbytes / step != process){
process = localreadbytes / step;
Systemoutprintln("上传进度:" + process);
//TODO 汇报上传状态
}
}
outflush();
rafclose();
outclose();
boolean result =ftpClientcompletePendingCommand();
if(remoteSize > 0){
status = resultUploadStatusUpload_From_Break_Success:UploadStatusUpload_From_Break_Failed;
}else {
status = resultUploadStatusUpload_New_File_Success:UploadStatusUpload_New_File_Failed;
}
return status;
}

public static void main(String[] args) {
ContinueFTP myFtp = new ContinueFTP();
try {
Systemerrprintln(myFtpconnect("10106236", 21, "5", "jieyan"));
// myFtpftpClientmakeDirectory(new String("歌曲"getBytes("GBK"),"iso-8859-1"));
// myFtpftpClientchangeWorkingDirectory(new String("歌曲"getBytes("GBK"),"iso-8859-1"));
// myFtpftpClientmakeDirectory(new String("爱你等于爱自己"getBytes("GBK"),"iso-8859-1"));
// Systemoutprintln(myFtpupload("E:\\ywflv", "/ywflv",5));
// Systemoutprintln(myFtpupload("E:\\爱你等于爱自己mp4","/爱你等于爱自己mp4"));
//Systemoutprintln(myFtpdownload("/爱你等于爱自己mp4", "E:\\爱你等于爱自己mp4"));
myFtpdisconnect();
} catch (IOException e) {
Systemoutprintln("连接FTP出错："+egetMessage());
}
}
}

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