1、* 在发送数据报时使用,它调用报文分割操作.* param file String硬盘文件*/public DataPacket(String file) this();try is = new FileInputStream(file);header.CalcHeaderInfo(is.available();this.madeBody();is.close();/this.Gereratedata();catch (FileNotFoundException ex) ex.printStackTrace(); catch (IOException ex1) ex1.printStackTr
2、ace();/* param url URL url地址public DataPacket(URL url) /is = url.openStream();URLConnection conn=url.openConnection();is=conn.getInputStream();int total=conn.getContentLength();header.CalcHeaderInfo(total); /System.out.println(total+:+total); is.close();catch (IOException ex) ex.printStackTrace(); /
3、* * 为发送构造分组,使用PackageHeader处理了报头格式,并为分组编序号.*/private void madeBody() al.clear();byte buffer;DataEntry de;for (int i = 0; i header.fragmentcounter; i+) ByteArrayOutputStream bos = new ByteArrayOutputStream();/is.skip(i * body.BODY_BUFFER_SIZE);header.ArrageSort(i);de = new DataEntry(PacketBody.BODY_B
4、UFFER_SIZE);de.setSn(i);de.setStreamsize(header.getStreamsize();de.setFragmentcounter(header.getFragmentcounter();if (header.isWTailFragment(i) buffer = new byteheader.getMinfragment();is.read(buffer, 0, buffer.length);header.setActByteSize(header.getMinfragment();de.setActByteSize(header.getMinfrag
5、ment(); else buffer = new bytebody.BODY_BUFFER_SIZE;is.read(buffer, 0, buffer.length);/System.out.println(length-+i+ +body.getBody().length+header.getMinfragment();body.setBody(buffer);length: + i + + header.toString();bos.write(header.getByte(), 0, header.HEADER_BUFFER_SIZE);bos.write(body.getBody(
6、), 0, body.getBody().length);de.setBytes(bos.toByteArray();al.add(de);* 为发送构造分组,没有考虑报头格式,也没有为分组编序号.private void madeBody1() if (header.isWTailFragment(i)is.read(body.getBody(), i * body.BODY_BUFFER_SIZE,header.getMinfragment();elsebody.BODY_BUFFER_SIZE);bos.write(body.getBody(), header.HEADER_BUFFER
7、_SIZE,body.getBody().length);al.add(bos);catch (IOException ex) ex.printStackTrace(); /* 在接收到报文后,对此报文执行组装,并处理报文丢失和乱序情况.* param b1 byte */public void Add(byte b1) byte buffer = (byte) b1.clone();handlerText(buffer); DataEntry de = new DataEntry(buffer, header.getActByteSize(); de.setSn(header.getSn()
8、; de.setStreamsize(header.getStreamsize(); de.setFragmentcounter(header.getFragmentcounter(); al.add(de);private void handlerText(byte buffer) ByteArrayOutputStream baos = new ByteArrayOutputStream(); baos.write(buffer, 0, header.HEADER_BUFFER_SIZE); byte b=new byteheader.HEADER_BUFFER_SIZE; System.
9、arraycopy(buffer,0,b,0,b.length); ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray(); InputStreamReader isr = new InputStreamReader(bais); BufferedReader br = new BufferedReader(isr); try header = new PacketHeader(br.readLine(); catch (Exception ex) ex.printStackTrace(); private
10、 String calFileSize(int size) return size / 1024 + K;public ArrayList getDataPackets() return al;/* 是否接收完毕,通过序号是否等于最大段数来判断,这也许有问题,比如,正好是最后一个段丢失了,这样* 这个包整个就丢失了.* returnpublic boolean isFull() return this.header.getSn() = this.header.getFragmentcounter() - 1 ? true : false;* 判断是否只有一个段.public boolean i
11、sZero() return this.header.getSn() = 0 ?* 该函数执行报文组装,不考虑丢失的报文.private ByteArrayOutputStream fetchDataPackets() ByteArrayOutputStream bos = new ByteArrayOutputStream(); byte buffer = null; DataEntry de; for (int i = 0;al.size();de = this.getSnData(i);buffer = de.getByte();if (header.getStreamsize() =
12、de.getStreamsize() bos.write(de.getByte(), header.HEADER_BUFFER_SIZE, de.getActByteSize(); System.out.println(de.toString() + - fetchDataPackets);catch (Exception ex) return bos;* 该函数执行报文组装,对于丢失的报文,写入空报文.* return ByteArrayOutputStream*/private ByteArrayOutputStream fetchDataPackets_sn() ByteArrayOut
13、putStream bos = new ByteArrayOutputStream(); byte buffer; DataEntry de; for (int i = 0;header.getFragmentcounter();try de = this.getSnData(i);if (de = null) de = seachDeData(i);buffer = de.getByte();/System.out.println(de.getSn() + + i);/handlerText(buffer);/bos.write(buffer, header.HEADER_BUFFER_SI
14、ZE,/ buffer.length - header.HEADER_BUFFER_SIZE);if (header.getStreamsize() = de.getStreamsize() bos.write(de.getByte(), header.HEADER_BUFFER_SIZE,de.getActByteSize(); /System.out.println(de.toString(); * 对缓冲的数据包进行排序处理,即按顺序提取同一帧的数据,如果没有找到该序号的帧,则返回空值.* param sn int 要找的帧序号. * return DataEntryprivate Da
15、taEntry getSnData(int sn) DataEntry de = null;de = (DataEntry) al.get(i);if (sn = de.getSn() break;else de = null; return de;* 按序号开始向前或者是向后寻找最近的帧片段,日后可以增加请求重发功能,通过开一个通信连接.* param sn int* return DataEntry private DataEntry seachDeData(int sn) DataEntry de = null; int initvalue, minvalue = 10000; Data
16、Entry back, fore = null;de = (DataEntry) al.get(i);if (header.getStreamsize() = de.getStreamsize() initvalue = Math.abs(de.getSn() - sn);if (de.getFragmentcounter() != de.getSn() & initvalue minvalue) minvalue = initvalue; fore = de; return fore;* 除去最后一帧外,随机抽取一帧.private DataEntry seachDeData() DataE
17、ntry de = null;System.out.println(sky : + de.getFragmentcounter() + + de.getSn() +if (de.getFragmentcounter() != de.getSn() * 生成组装完的结果数据.因为用图像来做测试,所以令其返回图像.* return Imagepublic java.awt.Image Gereratedata() ByteArrayInputStream bis;java.awt.image.BufferedImage bimage = null; byte b = fetchDataPacket
18、s_sn().toByteArray(); /fetchDataPackets_old1() bis = new ByteArrayInputStream; bimage = javax.imageio.ImageIO.read(bis);catch (Exception ex1) ex1.printStackTrace();return bimage;public static void main(String args) DataPacket dp = new DataPacket(e:nature14.jpg* 数据实体,充当临时处理场所.* author Administrator*c
19、lass DataEntry byte bytes;int fragmentcounter, sn, actbytesize;long streamsize;int minfragment; public DataEntry() public DataEntry(int size) this.actbytesize = size;public DataEntry(byte b, int i) this.bytes = b; this.actbytesize = i; public byte getByte() return this.bytes;public void setBytes(byt
20、e b) public void setStreamsize(long size) this.streamsize = size;public long getStreamsize() return this.streamsize;public int getMinfragment() return minfragment;public synchronized void setSn(int i) this.sn = i;public synchronized int getSn() return sn;public synchronized int getFragmentcounter() return fragmentcounter;public synchronized void setFragmentcounter(int c) this.fragmentcounter = c;public void setActByteSize(int size) actbytesize = size;public int getActByteSize() return actbytesize;public String toString() return this.streamsize + + this.fragmentcounter + + this.
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