J2me环境下实现Tar格式的打包

该类只实现J2me下Tar格式简单的打包方法（不支持目录打包），并没有实现解包方法。

Tar头文件格式为

Field OffsetField SizeField0100File name1008File mode1088Owner's numeric user ID1168Group's numeric user ID12412File size in bytes13612Last modification time in numeric Unix time format1488Checksum for header block1561Link indicator (file type)157100Name of linked file

The Link indicator field can have the following values:

Link indicator fieldValueMeaning'0'Normal file(ASCII NUL )Normal file (now obsolete)'1'Hard link '2'Symbolic link '3'Character special '4'Block special '5'Directory'6'FIFO '7'Contiguous file

 

package com.aws.tar;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.io.UnsupportedEncodingException;import java.util.Date;/** * 创建于 2011-05 * @author * toni001 * @email * [e-mail] * * <p> * The C structure for a Tar Entry's header is: * <pre> * struct header { *charname[NAMSIZ]; *charmode[8]; *charuid[8]; *chargid[8]; *charsize[12]; *charmtime[12]; *charchksum[8]; *charlinkflag; *charlinkname[NAMSIZ]; *charmagic[8]; *charuname[TUNMLEN]; *chargname[TGNMLEN]; *chardevmajor[8]; *chardevminor[8]; *} header; * </pre> * 文件内容以512字节为一个block进行分割，最后一个block不足部分以0补齐 * 两个文件的tar包首先存放第一个文件的tar头结构，然后存储文件内容，接着存储第二个文件的tar头结构，然后存储文件内容 * 所有文件都存储完了以后，最后存放一个全零的tar结构 * 所有的tar文件大小应该都是512的倍数，一个空文件打包后为512*3字节，包括一个tar结构头，一个全零的block存储文件内容，一个全零的tar结构 * */public class JtoTarLib {private final int HEADERNUM = 512,END=512,ENDS=512;//512//头文件各个信息占的长度private final int NAMELEN = 100;//文件名占据的字节数private final int FILEMODE = 8;//文件的权限private final int UID = 8;//用户private final int GID = 8;//用户组private final int FILESIZE = 12;//文件大小private final int UNIXTIME = 12;//UNIX时间戳private final int CHECKSUM = 8;//校正码//---------------------------------------------------//private final int FILETYPE = 1;//文件类型////FILETYPE//private final int NORMALFILE = 0x30; //普通文件//private final int DIRECTORY = 0x35;//文件目录//private int buff = 1024;//读取文件缓存private final byte[] IDBYTE = new byte[]{(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x30,(byte)0x20,(byte)0x00,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x30,(byte)0x20,(byte)0x00,};/** * 构造函数 * */public JtoTarLib(){//构造函数初始化内容}/** * 解压操作函数 * @param__tarIn * Tar输入流 * * */public void tarInputStream(InputStream __tarIn){}/** * 压缩操作函数 * @param__tarOut * Tar文件输出流 * @param__fileInList * 归档的文件列表 * Tar文件结构： * ---------------------------- * 头文件 512 byte * ---------------------------- * * ----------------------------- * @throws IOException * */public void tarOutputStream(OutputStream __tarOut , InputStream[] __fileInList , String[] __fileNameList) throws IOException{//压缩操作for(int i =0 ;i<__fileInList.length ;i++){__tarOut.write(jtoTarHandleHeader(__fileInList[i],__fileNameList[i]));tarFileContent(__tarOut, __fileInList[i]);__fileInList[i].close();//__tarOut.write(fileHandleFooter(i));System.gc();}__tarOut.write(jtoTarHandleFooter());__tarOut.close();}/** * @param__addFileInList * 追加到归档的文件列表 * */public void tarEntry(InputStream[] __addFileInList){//追加文件操作}/** * 操作文件头 * @param__tarIn * 文件输入流 * @param__fileName * 文件名 * @throws IOException * */private byte[] jtoTarHandleHeader(InputStream __tarIn,String __fileName) throws IOException{byte[] __tmp = new byte[HEADERNUM];int o = 0,p = 0,q = 0,r=0,s=0;for(int i=0 ;i<NAMELEN ;i++){__tmp[i] = fileNameByte(__fileName)[i];//文件名o+=__tmp[i];}for(int i=0 ;i<FILEMODE ;i++){__tmp[NAMELEN+i] = fileModeByte()[i];//文件权限p+=__tmp[NAMELEN+i];}for(int i=0 ;i<UID+GID;i++){__tmp[NAMELEN+FILEMODE+i] = IDBYTE[i];//用户组q+=__tmp[NAMELEN+FILEMODE+i];}for(int i=0 ;i<FILESIZE ;i++){__tmp[NAMELEN+FILEMODE+UID+GID+i] = fileSizeByte(Integer.toOctalString(__tarIn.available()))[i];//文件大小r+=__tmp[NAMELEN+FILEMODE+UID+GID+i];}for(int i=0 ;i<UNIXTIME ;i++){__tmp[NAMELEN+FILEMODE+UID+GID+FILESIZE+i] = //写入时间戳unixTimeByte(longToOctalString((new Date()).getTime()/1000))[i];s+=__tmp[NAMELEN+FILEMODE+UID+GID+FILESIZE+i];}int check = o+p+q+r+s+256;for(int i=0 ;i<CHECKSUM ;i++){__tmp[NAMELEN+FILEMODE+UID+GID+FILESIZE+UNIXTIME+i] = //写入校正信息fileChecksumByte(Integer.toOctalString(check))[i];s+=__tmp[NAMELEN+FILEMODE+UID+GID+FILESIZE+i];}//System.out.println(check);return __tmp;}/** * 写入内容 * @throws IOException * */private void tarFileContent(OutputStream __tarOut ,InputStream __tarIn) throws IOException{byte[] __tmp = new byte[buff];//缓存int e = END-__tarIn.available()%END;//System.out.println( e);//填充0的个数int len = 0;//写文件while ((len = __tarIn.read(__tmp)) > 0){__tarOut.write(__tmp, 0, len);} byte[] __end = new byte[e];__tarOut.write(__end);__tmp = null;//System.gc();} /** * 操作文件尾 * */private byte[] jtoTarHandleFooter(){return strPack(ENDS, "");//return strPack(960, "");} /** * 文件名字节 * */private byte[] fileNameByte(String __fileName){ //获取文件名字节return strPack(100, __fileName);}/** * 文件权限 * */private byte[] fileModeByte(){byte[] __tmp = new byte[FILEMODE];__tmp[0]=(byte)0x31;__tmp[1]=(byte)0x30;__tmp[2]=(byte)0x30;__tmp[3]=(byte)0x36;__tmp[4]=(byte)0x36;__tmp[5]=(byte)0x36;__tmp[6]=(byte)0x20;return __tmp;}/** * 写入文件大小 * */private byte[] fileSizeByte(String size){byte[] __tmp = new byte[]{(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20};int strlen = size.length();for(int i=FILESIZE-strlen,j=0;i<FILESIZE;i++,j++)__tmp[i-1]=size.getBytes()[j];return __tmp;} /** * 写入时间戳 * */private byte[] unixTimeByte(String time){byte[] __tmp = new byte[]{(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20};int strlen = time.length();for(int i=0;i<strlen;i++)__tmp[i]=time.getBytes()[i];return __tmp;}/** * 写入文件大小 * */private byte[] fileChecksumByte(String value){byte[] __tmp = new byte[]{(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x20,(byte)0x00,(byte)0x00};int strlen = value.length();for(int i=CHECKSUM-strlen,j=0;i<CHECKSUM;i++,j++)__tmp[i-2]=value.getBytes()[j];return __tmp;} /** * 将一段字符串 转换成占固定长度的字节数组，类似PHP中的pack方法 * @parambytelen * 字节长度 * @paramstr * 预转换字符串 * @return * 转换后字节的数组 * */public byte[] strPack(int bytelen ,String str){byte[] __tmp = new byte[bytelen];int strlen = 0;try {strlen = str.getBytes("GBK").length;for(int i=0;i<strlen;i++)__tmp[i]=str.getBytes("GBK")[i];} catch (UnsupportedEncodingException e) {e.printStackTrace();}return __tmp;}/** * 将long转换成8进制数 * J2ME中没有Long.toOctalString(Long l)方法 * * */private String longToOctalString(long l) {return toUnsignedString(l,3);} /** * Convert the integer to an unsigned number. */ private String toUnsignedString(long i, int shift) { final char[] digits = { '0' , '1' , '2' , '3' , '4' , '5' , '6' , '7' , '8' , '9' , 'a' , 'b' , 'c' , 'd' , 'e' , 'f' , 'g' , 'h' , 'i' , 'j' , 'k' , 'l' , 'm' , 'n' , 'o' , 'p' , 'q' , 'r' , 's' , 't' , 'u' , 'v' , 'w' , 'x' , 'y' , 'z' };char[] buf = new char[64];int charPos = 64;int radix = 1 << shift;long mask = radix - 1;do { buf[--charPos] = digits[(int)(i & mask)]; i >>>= shift;} while (i != 0);return new String(buf, charPos, (64 - charPos)); }public int getBuff() {return buff;}/** * 设置缓存大小 * */public void setBuff(int buff) {this.buff = buff;} }

demo类(j2se)

import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.util.Date;import com.aws.tar.JtoTarLib;public class testtar {InputStream in1 = this.getClass().getResourceAsStream("/t");InputStream in2 = this.getClass().getResourceAsStream("/tt");InputStream in3 = this.getClass().getResourceAsStream("/tar.png");InputStream in4 = this.getClass().getResourceAsStream("/tar.png");InputStream[] iss = new InputStream[]{in1,in2,in3,in4};public testtar(){System.out.println(Long.toOctalString((new Date()).getTime()/1000));}/** * @param args */public static void main(String[] args) {JtoTarLib jtotar = new JtoTarLib();testtar t = new testtar();FileOutputStream ff = null;File f= new File("f://t.tar");try {f.createNewFile();ff = new FileOutputStream(f);jtotar.tarOutputStream(ff, t.iss, new String[]{"t","tt","tar.png","tt.PNG"});} catch (IOException e) {e.printStackTrace();}finally{try {ff.close();} catch (IOException e) {e.printStackTrace();}}}}

贴图

(j2me)

import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import javax.microedition.io.Connector;import javax.microedition.io.file.FileConnection;import javax.microedition.midlet.MIDlet;import javax.microedition.midlet.MIDletStateChangeException;import com.aws.tar.JtoTarLib;public class TarMidlet extends MIDlet {FileConnection fc = null;JtoTarLib tarlib = null;InputStream i = null;InputStream i1=null;OutputStream out=null;public TarMidlet() {tarlib = new JtoTarLib();tarlib.setBuff( 1024*10);//设置缓存}protected void destroyApp(boolean arg0) throws MIDletStateChangeException {}protected void pauseApp() {}protected void startApp() throws MIDletStateChangeException {System.out.println("start");try { fc = (FileConnection)Connector.open("file:///e:/tt.tar"); if(fc.exists()){ fc.delete(); }fc.create();out = fc.openOutputStream();fc = (FileConnection)Connector.open("file:///e:/4-5-3.mp3");i= fc.openInputStream();fc = (FileConnection)Connector.open("file:///e:/4-5-4.mp3");i1= fc.openInputStream();tarlib.tarOutputStream(out, new InputStream[]{i,i1}, new String[]{"tt.mp3","tt1.mp3"});} catch (IOException e) {e.printStackTrace();}finally{try {fc.close();i.close();i1.close();out.close();} catch (Exception e) {e.printStackTrace();}}System.out.println("end");}}

第一次在CSDN写博客，转载注明出处。