說在前面:給我的需求是實現從服務器A將大量文件（大概幾十TB）發送到服務器B，在A服務器生成文件的MD5碼，並在服務器B進行md5驗證，驗證通過保存。
我的實現思路：
將待上傳的所有文件目錄生成一個txt文件，格式如下。前綴中，當後面的數字等於9999的時候，前面的數字會自行相加。（此處加前綴的目的是爲了整齊，而且失敗了便於查詢。）
AAA0000:D:\upload\addChannel.html
AAA0001:D:\upload\addChannel2.html
AAA0002:D:\upload\addContactPerson.html
AAA0003:D:\upload\admin.html
AAA0004:D:\upload\businessOfChannel.html
....
AAA9999:D:\upload\admin1.html
AAB0000:D:\upload\businessOfChannel1.html
...
每次讀取一條目錄，進行上傳。
本地測試版未去實現的部分，沒有把成功和失敗的目錄寫到文件中，也沒有添加日誌。
2017/07/07增加部分
添加部分註釋
添加對於大文件上傳的解決方案
2017/07/12增加部分
經過對代碼的研究以及測試表明，2017/07/07修改的大文件上傳有問題，問題出在bytebuffer的緩存有限制，byte.allocate(int)中的參數類型爲int，即最大緩存爲Integer.MAX_VALUE，即2^31-1的字節，大概是2G的大小。
如果確定文件不會大於2G的話，用2017/07/07的部分應該足夠，但是如果可以的話，依然推薦2017/07/12新增的部分代碼
新增的部分，不再原基礎上進行修改，而是新增代碼，只需要在客戶端和服務器調用方法的時候，將handler.sendData(socketChannel, path, pathPre)改成handler.sendData2(socketChannel, path, pathPre)，將this.handler.excute((ServerSocketChannel) s.channel())改成this.handler.excute2((ServerSocketChannel) s.channel())即可,當然在handler類中需要新增
相應的方法（excute2(),receiveData2(),sendData2()）
另外添加RequestObject類，用於替代execute方法中的RequestObject2類，在execute方法中使用。
在服務器端，原來是將接受到的文件先存到字節數組，然後對字節數組進行md5驗證，但是字節數組的大小依然受到Integer.MAX_VALUE的限制。所以現在改成，直接將接收到的字節數組寫入到文件，然後直接對文件進行MD5驗證。這樣excute2的方法會比之前邏輯有些變化。
代碼依然不夠整潔，需要後續繼續修改。
第一部分：將文件目錄存儲到文本中，文件夾不進行存儲。
import java.io.File;
import java.io.FileOutputStream;
public class ReadAllPaths {
private static final String rootPath="D:/upload/"; //the root path of the files which will be copied
private static final String filePath="G:/temp/unUploadedFilePath.txt";//the record of all files path
/*
* the items of prefix and num construct the path prefix,for example AAA0001
* and it's mainly convenient for searching
*/
private String prefix="AAA";
private int num=0;
/**
* main
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
ReadAllPaths paths=new ReadAllPaths();
File file=new File(filePath);
if(file.exists()){
file.delete();
}
FileOutputStream out=new FileOutputStream(file,true);
paths.getAllPaths(rootPath, out);
out.close();
}
/**
* get all path out
* @param root
* @param out
* @throws Exception
*/
private void getAllPaths(String root,FileOutputStream out) throws Exception{
File file=new File(root);
if(file.isDirectory()){
try{if(file.list().length==0){
return;
}else{
String[] files=file.list();
for(String f:files){
getAllPaths(root+f+File.separator, out);
}
}
}catch(NullPointerException npe){
return;
}
}else{
String pathNum=getPathNum();
String path=file.getAbsolutePath();
out.write((pathNum+":"+path+"\n").getBytes());
}
}
/**
* get the path prefix
* @return
*/
private String getPathNum(){
StringBuilder sb=new StringBuilder();
sb.append(getPrefix()).append(getNum());
setNum();
return sb.toString();
}
/**
* get the String prefix of path prefix
* @return
*/
private String getPrefix() {
return prefix;
}
/**
* set the String prefix of path prefix
* for example:AAA AAB AAC....AAZ ABA....AZZ BAA...
*/
private void setPrefix() {
char[] ch=new char[3];
ch=getPrefix().toCharArray();
if(ch[2]!='Z'){
ch[2]++;
}else{
ch[2]='A';
if(ch[1]!='Z'){
ch[1]++;
}else{
ch[1]='A';
ch[0]++;
}
}
prefix=new String(ch);
}
/**
* get the int prefix of path prefix
* @return
*/
private String getNum() {
StringBuffer sb=new StringBuffer();
if(num<10){
sb.append("000").append(num);
}else if(num<100){
sb.append("00").append(num);
}else if(num<1000){
sb.append("0").append(num);
}else{
sb.append(num);
}
return sb.toString();
}
/**
* set the int prefix of path prefix
* and the max num is 9999 and the min is 0000
*/
private void setNum() {
if(num<9999){
num++;
}else{
num=0;
setPrefix();
}
}
}第二部分，服務器端代碼
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.util.Iterator;
public class Server {
Selector selector = null;
ServerSocketChannel serverSocketChannel = null;
private NioserverHandler2 handler;
public Server() throws IOException {
selector = Selector.open();
// 打開服務器套接字通道
serverSocketChannel = ServerSocketChannel.open();
// 調整通道的阻塞模式非阻塞
serverSocketChannel.configureBlocking(false);
//serverSocketChannel.socket().setReuseAddress(true);這裏沒明白有什麼用，//所以註釋了
serverSocketChannel.socket().bind(new InetSocketAddress(9999));
serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
}
public Server(NioserverHandler2 handler) throws IOException {
this();
this.handler = handler;
while (selector.select() > 0) {
Iterator<SelectionKey> it = selector.selectedKeys().iterator();
while (it.hasNext()) {
SelectionKey s = it.next();
it.remove();
this.handler.excute((ServerSocketChannel) s.channel());
}
}
}
public static void main(String[] args) throws IOException {
new Server(new NioserverHandler2());
}
}
public class NioserverHandler2 {
//2017/07/07增加註釋
/*該目錄用於服務端文件的存儲。
*/
private final static String DIRECTORY = "G:\\NioRequest\\";
/*
*2017/07/07增加
*用於存儲上傳文件成功失敗情況的目錄,
*成功的放在succeed.log中
*格式爲客戶端傳過來的帶前綴的路徑，無特殊格式，每個一行
*失敗的放在failed.log中
*格式爲reason+帶前綴路徑
*/
private final static String ResultPath = "G:\\serverLog\\";
/*
*2017/07/07修改
*新增構造方法，檢測succeed.log，failed.log以及其目錄是否存在，不存在則創建
*/
public NioserverHandler2() {
File file = new File(ResultPath);
File file1 = new File(ResultPath + "succeed.log");
File file2 = new File(ResultPath + "failed.log");
if (!file.exists()) {
file.mkdirs();
}
if (!file1.exists()) {
try {
file1.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
if (!file2.exists()) {
try {
file2.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 這裏邊我們處理接收和發送
*
* @param serverSocketChannel
*/
public void excute(ServerSocketChannel serverSocketChannel) {
SocketChannel socketChannel = null;
/*
*2017/07/07增加該字段
*自己測試中發現，有些文件可以讀寫執行，但是卻無法正確發送
*所以在client發送的fileInfo中新增了一個字段，如果把文件讀取到字節數組失敗
*則設置字節數組爲空
*此時字節數組爲空有兩種情況：
*文件爲0KB大小，還有上面的一種情況，
*前者需要直接新建一個空文件，後者需要報錯
*所以client端新增一個字段，用於區分這兩種情況。
*第一種情況是fileInfo中設置一個well字符串
*第二種情況是fileInfo中設置一個error字符串
*
*此處新增的status由於區分不同情況
*status==0 文件傳送正確，並且MD5驗證通過
*status==1 文件傳送正確，但是MD5驗證未通過
*status==2 文件傳輸失敗
*以後如果有新的錯誤，會在這裏繼續追加狀態
*/
int status=0;
try {
socketChannel = serverSocketChannel.accept(); // 等待客戶端連接
RequestObject2 requestObject = receiveData(socketChannel);// 接數據
//md5驗證，用的是apache的，2017/07/07添加註釋
String md5 = DigestUtils.md5Hex(requestObject.getContents());
//用於對客戶端的相應，其實在本程序中用處不太大
String response = "";
//2017/07/07添加該字段，用於判斷成功失敗
boolean flag=true;
/*
*2017/07/07對於判斷進行修改，新增了判斷status字段是否爲error
*至於下面的responseObject不用關於，只是爲了方便固定格式的字符串而已
*/
if(requestObject.getStatus().equals("error")){
flag=false;
status=2;
response = (new ResponseObject("failed", requestObject.getAbsolutePath(), "fail error")).toString();
}else{
if (md5.equals(requestObject.getMd5())) {
response = (new ResponseObject("succeed", requestObject.getAbsolutePath(), "")).toString();
File file = new File(DIRECTORY + requestObject.getRelativePath());
if (!file.exists()) {
file.mkdirs();
}
File file1 = new File(DIRECTORY + requestObject.getRelativePath() + requestObject.getFilename());
if (!file1.exists()) {
file1.createNewFile();
}
FileOutputStream fos = new FileOutputStream(file1);
fos.write(requestObject.getContents());
fos.close();
} else {
flag=false;
status=1;
response = (new ResponseObject("failed", requestObject.getAbsolutePath(), "md5驗證失敗")).toString();
}
}
//將處理結果寫入到succeed.log和failed.log中
writeRusultToFile(flag, requestObject.getAbsolutePath(),status);
//響應客戶端
responseData(socketChannel, response);
} catch (IOException e) {
e.printStackTrace();
}
}
/*
*2017/07/12新增代碼
*md5驗證方式從驗證字節數組改成驗證文件流。
*將之前寫入文件的部分代碼刪除，因爲在receiveData2已經將文件進行了寫入。
*
*/
public void excute2(ServerSocketChannel serverSocketChannel) {
SocketChannel socketChannel = null;
int status=0;
try {
socketChannel = serverSocketChannel.accept(); // 等待客戶端連接
RequestObject requestObject = receiveData2(socketChannel);// 接數據
String md5 = DigestUtils.md5Hex(new FileInputStream(new File(DIRECTORY+requestObject.getRelativePath()+requestObject.getFilename())));
System.out.println(md5);
String response = "";
boolean flag = true;
if(requestObject.getStatus().equals("error")){
flag=false;
status=2;
response = (new ResponseObject("failed", requestObject.getAbsolutePath(), "fail error")).toString();
}else{
if (md5.equals(requestObject.getMd5())) {
response = (new ResponseObject("succeed", requestObject.getAbsolutePath(), "")).toString();
} else {
flag=false;
status=1;
response = (new ResponseObject("failed", requestObject.getAbsolutePath(), "md5驗證失敗")).toString();
}
}
writeRusultToFile(flag, requestObject.getAbsolutePath(),status);
System.out.println(response);
responseData(socketChannel, response);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* <p>
* 讀取通道中的數據到Object裏去
* </p>
*
* @param socketChannel
* @return
* @throws IOException
*/
public RequestObject2 receiveData(SocketChannel socketChannel) throws IOException {
// 文件名
String fileName = null;
String relativePath = null;
String absolutePath = null;
String md5 = null;
//2017/07/07新增字段，因爲RequestObject2字段進行了修改，所以添加
String status=null;
// 文件長度
int contentLength = 0;
// 文件內容
byte[] contents = null;
// 由於我們解析時前4個字節是文件名長度
int capacity = 4;
ByteBuffer buf = ByteBuffer.allocate(capacity);
int size = 0;
byte[] bytes = null;
// 拿到文件名的長度
size = socketChannel.read(buf);
if (size >= 0) {
buf.flip();
capacity = buf.getInt();
buf.clear();
}
buf = ByteBuffer.allocate(capacity);
size = socketChannel.read(buf);
if (size >= 0) {
buf.flip();
bytes = new byte[size];
buf.get(bytes);
buf.clear();
}
String fileInfo = new String(bytes);
System.out.println(fileInfo);
/*2017/07/07增加註釋，並添加字段
*並進行部分修改
*/
status=fileInfo.split(";")[0];
fileName = fileInfo.split(";")[1];
relativePath = fileInfo.split(";")[2];
absolutePath = fileInfo.split(";")[3];
md5 = fileInfo.split(";")[4];
// 拿到文件長度
capacity = 4;
buf = ByteBuffer.allocate(capacity);
size = socketChannel.read(buf);
if (size >= 0) {
buf.flip();
// 文件長度是可要可不要的，如果你要做校驗可以留下
capacity = buf.getInt();
buf.clear();
}
if (capacity == 0) {
contents = new byte[] {};
} else {
// 用於接收buffer中的字節數組
ByteArrayOutputStream baos = new ByteArrayOutputStream();
// 文件可能會很大
// capacity = 1024;
buf = ByteBuffer.allocate(capacity);
while ((size = socketChannel.read(buf)) >= 0) {
buf.flip();
bytes = new byte[size];
buf.get(bytes);
baos.write(bytes);
buf.clear();
}
contents = baos.toByteArray();
}
RequestObject2 requestObject = new RequestObject2(fileName, relativePath, absolutePath, md5, contents,status);
return requestObject;
}
private void responseData(SocketChannel socketChannel, String response) {
ByteBuffer buffer = ByteBuffer.wrap(response.getBytes());
try {
socketChannel.write(buffer);
buffer.clear();
// 確認要發送的東西發送完了關閉output 不然它端接收時socketChannel.read(Buffer)
// 很可能造成阻塞 ，可以把這個（L）註釋掉，會發現客戶端一直等待接收數據
socketChannel.socket().shutdownOutput();// （L）
} catch (IOException e) {
e.printStackTrace();
}
}
/*
*2017/07/12新增方法，用於excute2()方法
*大部分代碼和2017/07/07的代碼相似，因爲客戶端發送的文件大小可能超出int類型，所以改成long類型，所以服務端也自然進行了修改
*因爲可能文件過大，所以直接將接收到的字節數組寫入到文件中。
*這裏的註釋可能比較少
*/
public RequestObject receiveData2(SocketChannel socketChannel) throws IOException {
String status=null;
String fileName = null;
String relativePath = null;
String absolutePath = null;
String md5 = null;
int contentLength = 0;
// 由於我們解析時前4個字節是文件名長度
int capacity = 4;
ByteBuffer buf = ByteBuffer.allocate(capacity);
int size = 0;
byte[] bytes = null;
// 拿到文件名的長度
size = socketChannel.read(buf);
if (size >= 0) {
buf.flip();
capacity = buf.getInt();
buf.clear();
}
buf = ByteBuffer.allocate(capacity);
size = socketChannel.read(buf);
if (size >= 0) {
buf.flip();
bytes = new byte[size];
buf.get(bytes);
buf.clear();
}
status = fileInfo.split(";")[0];
fileName = fileInfo.split(";")[1];
relativePath = fileInfo.split(";")[2];
absolutePath = fileInfo.split(";")[3];
md5 = fileInfo.split(";")[4];
// 拿到文件長度，因爲long類型佔8個字節，所以這裏爲8
capacity = 8;
buf = ByteBuffer.allocate(capacity);
size = socketChannel.read(buf);
long cap=0;
if (size >= 0) {
buf.flip();
// 文件長度顯得不那麼重要了
cap = buf.getLong();
buf.clear();
}
System.out.println(cap);
if (status.equals("well")) {
File file = new File(DIRECTORY + relativePath);
if (!file.exists()) {
file.mkdirs();
}
File file1 = new File(DIRECTORY + relativePath + fileName);
if (!file1.exists()) {
file1.createNewFile();
}
FileOutputStream fos=new FileOutputStream(file1);
//每次接受1KB的字節數組，可以根據需要自己修改。注意有Integet.MAXVALUE的限制。
buf = ByteBuffer.allocate(1024);
while ((size = socketChannel.read(buf)) >= 0) {
buf.flip();
bytes = new byte[size];
buf.get(bytes);
fos.write(bytes);
buf.clear();
}
fos.close();
}
RequestObject requestObject = new RequestObject(fileName, relativePath, absolutePath, md5,status);
return requestObject;
}
}
import java.io.Serializable;
public class RequestObject2 implements Serializable {
private static final long serialVersionUID = 1L;
private String filename;
private String relativePath;
private String absolutePath;
private String md5;
private byte[] contents;
private String status;
public RequestObject2(String filename, String relativePath, String absolutePath, String md5, byte[] contents,String status) {
this.filename = filename;
this.relativePath = relativePath;
this.absolutePath = absolutePath;
this.md5 = md5;
this.contents = contents;
this.status=status;
}
public String getFilename() {
return filename;
}
public String getRelativePath() {
return relativePath;
}
public String getAbsolutePath() {
return absolutePath;
}
public String getMd5() {
return md5;
}
public byte[] getContents() {
return contents;
}
public String getStatus(){
return status;
}
}
/*
*2017/07/12新增類，用於excute2方法
*想對於RequestObject，刪除了byte[]
*/
import java.io.Serializable;
public class RequestObject implements Serializable {
private static final long serialVersionUID = 1L;
private String filename;
private String relativePath;
private String absolutePath;
private String md5;
private String status;
public RequestObject(String filename, String relativePath, String absolutePath, String md5, String status) {
this.filename = filename;
this.relativePath = relativePath;
this.absolutePath = absolutePath;
this.md5 = md5;
this.status = status;
}
public String getFilename() {
return filename;
}
public String getRelativePath() {
return relativePath;
}
public String getAbsolutePath() {
return absolutePath;
}
public String getMd5() {
return md5;
}
public String getStatus() {
return status;
}
} 第三部分 客戶端代碼
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
public class Client2 {
/*
*2017/07/07添加該註釋
*用於存儲要被上傳文件的目錄，即文章第一部分代碼生成文件的位置
*/
private static final String unpath = "G:\\temp\\unUploadedFilePath.txt";
/*
*2017/07/07添加該註釋
*待上傳文件所在的目錄
*還有一個作用，用於獲得相對路徑
*/
private static final String pathPre = "D:\\upload\\";
//2017/07/07添加該註釋
//服務器地址，因爲是本地測試，所以用這個
private static final String IPADDR = "127.0.0.1";
//2017/07/07添加該註釋
//服務端口號
private static final int PORT = 9999;
Selector selector;
public Client2() throws IOException {
selector = Selector.open();
new Thread(new SendDataRunnable()).start();
}
private class SendDataRunnable implements Runnable {
private ClientHandler handler;
public SendDataRunnable() {
handler = new ClientHandler();
}
@Override
public void run() {
try {
BufferedReader reader = new BufferedReader(new FileReader(new File(unpath)));
String path = "";
while ((path = reader.readLine()) != null && path.length() != 0) {
SocketChannel socketChannel;
socketChannel = SocketChannel.open();
socketChannel.connect(new InetSocketAddress(IPADDR, PORT));
socketChannel.configureBlocking(false);
socketChannel.register(selector, SelectionKey.OP_READ);
handler.sendData(socketChannel, path, pathPre);
String response = handler.receiveData(socketChannel);
System.out.println(response);
socketChannel.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
public static void main(String[] args) throws IOException {
Client2 client = new Client2();
}
}
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.SocketChannel;
import org.apache.commons.codec.digest.DigestUtils;
public class ClientHandler {
public void sendData(SocketChannel socketChannel,String path,String pathPre)throws Exception{
System.out.println(path);
String absoluteFilePath=getAbsoluteFilePath(path);
String fileName=getFileName(absoluteFilePath);
String relativeFilePath=getRelativeFilePath(absoluteFilePath, pathPre,fileName);
System.out.println(absoluteFilePath);
/*
*2017/07/07添加該字段
*用於區分文件是否正確讀取
*/
String status="well";
byte[] bytes=makeFileToBytes(absoluteFilePath);
System.out.println(bytes.length);
String md5=DigestUtils.md5Hex(bytes);
/*
*2017/07/07添加該註釋
*進行部分修改，增加status部分
*/
String fileInfo=new StringBuffer()
.append(status)
.append(";")
.append(fileName)
.append(";")
.append(relativeFilePath)
.append(";")
.append(path)
.append(";")
.append(md5)
.toString();
System.out.println(fileInfo);
ByteBuffer buffer = ByteBuffer.allocate(8 +fileInfo.getBytes().length+bytes.length);
buffer.putInt(fileInfo.getBytes().length);
buffer.put(fileInfo.getBytes());
buffer.putInt(bytes.length);
buffer.put(ByteBuffer.wrap(bytes));
buffer.flip();
/*
*2017/07/07進行修改
*之前沒有外面的while循環，發現大文件server端一直接收失敗
*所以進行的添加。
*/
while (buffer.hasRemaining()) {
socketChannel.write(buffer);
}
buffer.clear();
// 關閉輸出流防止接受時阻塞，就是告訴接收方本次的內容已經發完了，你不用等了
socketChannel.socket().shutdownOutput();
}
/*
*2017/07/12新增代碼
*/
public void sendData2(SocketChannel socketChannel, String path, String pathPre) {
System.out.println(path);
String absoluteFilePath = getAbsoluteFilePath(path);
File file = new File(absoluteFilePath);
String fileName = getFileName(absoluteFilePath);
String relativeFilePath = getRelativeFilePath(absoluteFilePath, pathPre, fileName);
System.out.println(absoluteFilePath);
String status = "well";
String md5 = null;
int bufferSize = 1024;//用於每次發送文件的大小設置，可以自行修改
try {
RandomAccessFile rafi = new RandomAccessFile(absoluteFilePath, "r");
byte[] buf = new byte[bufferSize];
int c = 0;
try {
c = rafi.read(buf);
FileInputStream fis = new FileInputStream(new File(absoluteFilePath));
md5 = DigestUtils.md5Hex(fis);
fis.close();
} catch (Exception e) {
c = 0;
status = "error";
md5 = "0";
}
String fileInfo = new StringBuffer().append(status).append(";").append(fileName).append(";")
.append(relativeFilePath).append(";").append(path).append(";").append(md5).toString();
System.out.println(fileInfo);
int len = c;
//這裏注意下12，因爲之前是發送兩個int類型，所以是8，現在是一個int一個long，所以12
ByteBuffer buffer = ByteBuffer.allocate((int) (12 + fileInfo.getBytes().length + bufferSize));
buffer.putInt(fileInfo.getBytes().length);
buffer.put(fileInfo.getBytes());
buffer.putLong(len > 0 ? file.length() : 0);
/*
*說下flag的作用
*flag==true 表示這次發送的是一個buffersize的大小，可能後續還有字節數組沒發送完成，需要繼續判斷；另外當c==0的時候，true的作用是用於後面發送文件的基本信息。
*flag==false表示這次發送的不是一個buffersize的大小，也表示已經發送完成，無需後續判斷
*/
boolean flag = true;
while(c>0){
if (c == buf.length) {
buffer.put(ByteBuffer.wrap(buf));
flag = true;
} else {
buffer.put(ByteBuffer.wrap(buf, 0, c));
c = 0;
flag = false;
}
buffer.flip();
while (buffer.hasRemaining()) {
socketChannel.write(buffer);
}
if(flag) {
buffer.clear();
c = rafi.read(buf);
}
}
if(flag){
buffer.flip();
while (buffer.hasRemaining()) {
socketChannel.write(buffer);
}
}
rafi.close();
buffer.clear();
// 關閉輸出流防止接受時阻塞，就是告訴接收方本次的內容已經發完了，你不用等了
socketChannel.socket().shutdownOutput();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
*2017/07/07添加註釋
*用於從類似AAA0000:D:\upload\addChannel.html格式的目錄中讀取真正的文件目錄
*/
private String getAbsoluteFilePath(String path){
return path.substring(8);
}
/*
*2017/07/07添加註釋
*用於從類似D:\upload\addChannel.html格式的目錄中拿到被存儲的相對路徑(說的啥啊，自己都看不懂)
*舉個例子：
*客戶端文件目錄D:\upload\test1\test2\addChannel.html，即爲下面的absoluteFilePath
*我想存儲到服務器的 G:\NioRequest\test1\test2\addChannel.html
*所以我要獲得客戶端目錄的test1\test2\addChannel.html部分
*然後拼接到服務器的目錄G:\NioRequest\目錄上
*下面的pathPre是爲前綴，上面例子中就是D:\upload\
*因爲我要的目錄中不包括文件名，所以加了個文件名字段
*/
private String getRelativeFilePath(String absoluteFilePath,String pathPre,String fileName){
return absoluteFilePath.substring(pathPre.length(),absoluteFilePath.length()-fileName.length());
}
/*
*2017/07/07添加註釋
*這個太簡單，不解釋
*/
private String getFileName(String path){
return new File(path).getName();
}
/*
*2017/07/07添加註釋
*將文件讀取到字節數組，不是我自己寫的，網上找到的
*/
private byte[] makeFileToBytes(String filePath){
File file=new File(filePath);
byte[] ret = null;
try {
FileInputStream in = new FileInputStream(file);
ByteArrayOutputStream out = new ByteArrayOutputStream(4096);
byte[] b = new byte[4096];
int n;
while ((n = in.read(b)) != -1) {
out.write(b, 0, n);
}
in.close();
out.close();
ret = out.toByteArray();
} catch (IOException e) {
// log.error("helper:get bytes from file process error!");
e.printStackTrace();
}
return ret;
}
public String receiveData(SocketChannel socketChannel) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
String response = "";
try {
ByteBuffer buffer = ByteBuffer.allocate(1024);
byte[] bytes;
int count = 0;
while ((count = socketChannel.read(buffer)) >= 0) {
buffer.flip();
bytes = new byte[count];
buffer.get(bytes);
baos.write(bytes);
buffer.clear();
}
bytes = baos.toByteArray();
response = new String(bytes, "UTF-8");
// socketChannel.socket().shutdownInput();
} finally {
try {
baos.close();
} catch (Exception ex) {
}
}
return response;
}
}/*至此全部完成，註釋不夠多，部分代碼是從網上找的。後期有時間會補全註釋的，或者下次直接上最終使用的代碼*/