Java实现bt文件下载、制作、解析、磁力链接

     首先torrent里面肯定携带的有一些信息，所以就需要我们来解析这些信息。

     我们这里做多文件制作torrent，所以首先要针对每一个文件建一个实体类

import java.util.List;public class Info {private String name;    private byte[] pieces;    private long piecesLength;    private long length;    private String md5sum;    private List<Files> files;    public Info() {    }public Info(String name, byte[] pieces, long piecesLength, long length, String md5sum, List<Files> files) {super();this.name = name;this.pieces = pieces;this.piecesLength = piecesLength;this.length = length;this.md5sum = md5sum;this.files = files;}public String getName() {return name;}public void setName(String name) {this.name = name;}public byte[] getPieces() {return pieces;}public void setPieces(byte[] pieces) {this.pieces = pieces;}public long getPiecesLength() {return piecesLength;}public void setPiecesLength(long piecesLength) {this.piecesLength = piecesLength;}public long getLength() {return length;}public void setLength(long length) {this.length = length;}public String getMd5sum() {return md5sum;}public void setMd5sum(String md5sum) {this.md5sum = md5sum;}public List<Files> getFiles() {return files;}public void setFiles(List<Files> files) {this.files = files;}

      而对于每一个File,又存在了一些信息,所以我们针对File建立一个实体类

      

import java.util.List;public class Files {private long length;    private String md5sum;    private List<String> path;    public Files() {    }    //getter and setter  and tostring    public long getLength() {return length;}public Files(long length, String md5sum, List<String> path) {super();this.length = length;this.md5sum = md5sum;this.path = path;}public void setLength(long length) {this.length = length;}public String getMd5sum() {return md5sum;}public void setMd5sum(String md5sum) {this.md5sum = md5sum;}public List<String> getPath() {return path;}public void setPath(List<String> path) {this.path = path;}}

而我们在制作torrent文件时，填写了很多信息，比如要web seeds等等。所以此时也需要一个实体类

import java.util.Arrays;import java.util.List;import org.jeecgframework.core.util.StringUtil;public class BitTorrentInfo {public static List<String> keyList;    static{        String[] keys = {"announce", "announce-list", "creation date", "comment", "created by",                "info", "length", "md5sum", "name", "piece length","pieces", "files", "path"};        keyList = Arrays.asList(keys);    }    private String announce;    private List<String> announceList;    private long creationDate;    private String comment;    private String createBy;    private Info info;    public BitTorrentInfo() {    }    //getter and setter  and tostring    public BitTorrentInfo(String announce, List<String> announceList, long creationDate, String comment,String createBy, Info info) {super();this.announce = announce;this.announceList = announceList;this.creationDate = creationDate;this.comment = comment;this.createBy = createBy;this.info = info;}    public static List<String> getKeyList() {return keyList;}public static void setKeyList(List<String> keyList) {BitTorrentInfo.keyList = keyList;}public String getAnnounce() {return announce;}public void setAnnounce(String announce) {this.announce = announce;}public List<String> getAnnounceList() {return announceList;}public void setAnnounceList(List<String> announceList) {this.announceList = announceList;}public long getCreationDate() {return creationDate;}public void setCreationDate(long creationDate) {this.creationDate = creationDate;}public String getComment() {return comment;}public void setComment(String comment) {this.comment = comment;}public String getCreateBy() {return createBy;}public void setCreateBy(String createBy) {this.createBy = createBy;}public Info getInfo() {return info;}public void setInfo(Info info) {this.info = info;}public void setValue(String key, Object value) throws Exception {        if(!keyList.contains(key)){            throw new Exception("not contains this key: " + key);        }else{            switch (key){                case "announce":this.setAnnounce(value.toString());break;                case "announce-list":this.getAnnounceList().add(value.toString());break;                case "creation date":                if(StringUtil.isNumeric(value.toString())){                this.setCreationDate(Long.parseLong(value.toString()));                }else{                this.setCreationDate(0);                }                break;                case "comment":this.setComment(value.toString());break;                case "created by":this.setCreateBy(value.toString());break;                case "length":                    List<Files> filesList1 = this.getInfo().getFiles();                    if(filesList1 != null){                        Files files = this.getInfo().getFiles().get(filesList1.size()-1);                        files.setLength(Long.parseLong(value.toString()));                    }else {                        this.getInfo().setLength(Long.parseLong(value.toString()));                    }                    break;                case "md5sum":                    List<Files> filesList2 = this.getInfo().getFiles();                    if(filesList2 != null){                        Files files = this.getInfo().getFiles().get(filesList2.size()-1);                        files.setMd5sum(value.toString());                    }else {                        this.getInfo().setMd5sum(value.toString());                    }                    break;                case "name":                    this.getInfo().setName(value.toString());                    break;                case "piece length":                    this.getInfo().setPiecesLength(Long.parseLong(value.toString()));                    break;                case "pieces":                if(StringUtil.isNumeric(value.toString())){                this.getInfo().setPieces(null);                }else{                this.getInfo().setPieces((byte[])value);                }                    break;                case "path":                    List<Files> filesList3 = this.getInfo().getFiles();                    Files files3 = filesList3.get(filesList3.size()-1);                    files3.getPath().add(value.toString());                    break;            }        }    }    }

解析实体类

import java.io.File;import java.io.FileInputStream;import java.io.InputStream;import java.util.LinkedList;import java.util.List;public class BitTorrents {public static BitTorrentInfo parse(File btFile) throws Exception {        return new BitTorrents().analyze(new FileInputStream(btFile));    }    public static BitTorrentInfo parse(String btFilePath) throws Exception {        return new BitTorrents().analyze(new FileInputStream(btFilePath));    }    private BitTorrentInfo analyze(InputStream is) throws Exception {        BitTorrentInfo btInfo = new BitTorrentInfo();        String key = null;        StringBuilder strLengthBuilder = new StringBuilder();        int tempByte;        while ((tempByte = is.read()) != -1) {            char temp = (char) tempByte;            switch (temp) {                case 'i':                    StringBuilder itempBuilder = new StringBuilder();                    char iTemp;                    while ((iTemp = (char) is.read()) != 'e') {                        itempBuilder.append(iTemp);                    }                    btInfo.setValue(key, itempBuilder.toString());                    break;                case '0': case '1': case  '2': case '3': case '4': case  '5': case '6': case '7': case '8': case '9':                    strLengthBuilder.append(temp);                    break;                case ':':                    int strLen = Integer.parseInt(strLengthBuilder.toString());                    strLengthBuilder = new StringBuilder();                    byte[] tempBytes = new byte[strLen];                    is.read(tempBytes);                    if (key != null && key.equals("pieces")) {                        btInfo.setValue(key, tempBytes);                    } else {                        String tempStr = new String(tempBytes);                        if (BitTorrentInfo.keyList.contains(tempStr)) {                            key = tempStr;                            if (tempStr.equals("announce-list")) {                                btInfo.setAnnounceList(new LinkedList<String>());                            } else if (tempStr.equals("info")) {                                btInfo.setInfo(new Info());                            } else if (tempStr.equals("files")) {                                btInfo.getInfo().setFiles(new LinkedList<Files>());                                btInfo.getInfo().getFiles().add(new Files());                            } else if (tempStr.equals("length")) {                                List<Files> tempFiles = btInfo.getInfo().getFiles();                                if (tempFiles != null) {                                    if (tempFiles.isEmpty() || tempFiles.get(tempFiles.size() - 1).getLength() != 0) {                                        tempFiles.add(new Files());                                    }                                }                            } else if (tempStr.equals("md5sum")) {                                List<Files> tempFiles = btInfo.getInfo().getFiles();                                if (tempFiles != null) {                                    if (tempFiles.isEmpty() || tempFiles.get(tempFiles.size() - 1).getMd5sum() != null) {                                        tempFiles.add(new Files());                                    }                                }                            } else if (tempStr.equals("path")) {                                List<Files> tempFilesList = btInfo.getInfo().getFiles();                                if (tempFilesList.isEmpty()) {                                    Files files = new Files();                                    files.setPath(new LinkedList<String>());                                    tempFilesList.add(files);                                } else {                                    Files files = tempFilesList.get(tempFilesList.size() - 1);                                    if (files.getPath() == null) {                                        files.setPath(new LinkedList<String>());                                    }                                }                            }                        } else {                            btInfo.setValue(key, tempStr);                        }                    }                    break;            }        }        return btInfo;    }    public static void main(String[] args) throws Exception {    BitTorrentInfo info=parse("E://xx/xx.torrent");        System.out.println("信息:"+info.getAnnounce()+"\t"+info.getComment()+"\t"+info.getCreateBy()+"\t"+GetDate.LongConvetDateTime(info.getCreationDate()));        Info it=info.getInfo();        System.out.println("信息:"+it.getName()+"\t"+it.getPiecesLength()+"\t"+it.getLength()+"\t"+it.getMd5sum()+"\t"+it.getPieces());        if(info.getAnnounceList().size()>0){        for(String str:info.getAnnounceList()){        System.out.println("信息2:"+str);        }        }        if(it.getFiles().size()>0){        for(Files file: it.getFiles()){        System.out.println("信息3:"+file.getLength()+"\t"+file.getMd5sum());        if(file.getPath().size()>0){        for(String str:file.getPath()){        System.out.println("信息4："+str);        }        }        }        }    }}