http断点续传简单实现（java)

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0 发表于: 2006-05-10

/*
**SiteFileFetch.java
*/
package NetFox;
import java.io.*;
import java.net.*;

public class SiteFileFetch extends Thread {

SiteInfoBean siteInfoBean = null; //文件信息Bean
long[] nStartPos; //开始位置
long[] nEndPos; //结束位置
FileSplitterFetch[] fileSplitterFetch; //子线程对象
long nFileLength; //文件长度
boolean bFirst = true; //是否第一次取文件
boolean bStop = false; //停止标志
File tmpFile; //文件下载的临时信息
DataOutputStream output; //输出到文件的输出流

//负责整个文件的抓取，控制内部线程（FileSplitterFetch类）
public SiteFileFetch(SiteInfoBean bean) throws IOException
{
siteInfoBean = bean;
//tmpFile = File.createTempFile ("zhong","1111",new File(bean.getSFilePath()));
tmpFile = new File(bean.getSFilePath()+File.separator + bean.getSFileName()+".info");
if(tmpFile.exists ())
{
bFirst = false;
read_nPos();
}
else
{
nStartPos = new long[bean.getNSplitter()];
nEndPos = new long[bean.getNSplitter()];
}

}

public void run()
{
//获得文件长度
//分割文件
//实例FileSplitterFetch
//启动FileSplitterFetch线程
//等待子线程返回
try{
if(bFirst)
{
nFileLength = getFileSize();
if(nFileLength == -1)
{
System.err.println("File Length is not known!");
}
else if(nFileLength == -2)
{
System.err.println("File is not access!");
}
else
{
for(int i=0;i<nStartPos.length;i++)
{
nStartPos = (long)(i*(nFileLength/nStartPos.length)); 5H2Ugk3
} ]sDlZJX<M
for(int i=0;i<nEndPos.length-1;i++) }u.I%{4
{ y_M,p?]^,
nEndPos = nStartPos[i+1]; l.uW>AoLh
} 5ajd$t
nEndPos[nEndPos.length-1] = nFileLength; tHmV4H$
} 534DAhpD=.
} ZC97Z sE
7|DPevrk
[5-3PuT&9
//启动子线程 !bBx'
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; mvu$
for(int i=0;i<nStartPos.length;i++) y4%[^g~-
{ %\B@!4]
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), M7.H;.?
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), ~j yl
nStartPos,nEndPos,i); {JtfEna
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); /Jc54d
fileSplitterFetch.start(); )@_5}8
} cuQAXqXC@
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), lZJbQ=K{
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ^=arKp,?5
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", M)G|K a
nEndPos = " + nFileLength); &~"e["gF=
// fileSplitterFetch[nPos.length-1].start(); c JOT{
ei!Yxw8d
!h70<Q^
//等待子线程结束 ozkmZ;
//int count = 0; 3M"eAK([
//是否结束while循环 j/, I)Za
boolean breakWhile = false; h|N!U/(U
y eWB.M~X
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while(!bStop) -'uz%2 {
{ cd.|>
write_nPos(); lbm ,#
Utility.sleep(500); -] `OaL!
breakWhile = true; m`xzvg
>{eGSSG0
"qhQJql
for(int i=0;i<nStartPos.length;i++) HFW8x9Cc
{ >dfk2.6e
if(!fileSplitterFetch.bDownOver) #;hYJ Y
{ \@$V^;OP/
breakWhile = false; &5n0J
break; Qsg([K
} wZb77
} Qq<+QL|
if(breakWhile) Eb89B%L62G
break; HME`7dw?
p9gX$-!pbG
\*\)zj*r
//count++; W+BHt{
//if(count>4) bj_oA i
// siteStop(); .-}F~FES
} QygbfW6u
+K:hetv
]dL#k>$0q
System.err.println("文件下载结束！"); 6Gh3r
} 1? Im"
catch(Exception e){e.printStackTrace ();} <CN+VXF
} RP%7M8V){B
G$E+qk nJL
}5=tUfh)]'
//获得文件长度 li&&[=6A
public long getFileSize() )BmO[AiOM
{ p* tAwl
int nFileLength = -1; 6MmkEU z
try{ 5^Ps(8VbS
URL url = new URL(siteInfoBean.getSSiteURL()); l [ Navw
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); H",q-.!
httpConnection.setRequestProperty("User-Agent","NetFox"); Mb'Tx
;fZ9:WB
p~17cH4~-f
int responseCode=httpConnection.getResponseCode(); JQH>{OB
if(responseCode>=400) =4804N7
{ et}%E9
processErrorCode(responseCode); %Iv*u sXP
return -2; //-2 represent access is error ,o sM|!,
} DgKe!w$
7(B"3qF8|
N.?)s.D(
String sHeader; a$]i8AeG
jn+BH3e
o$k9$H>Na
for(int i=1;;i++) u9D#5NvGs
{ >_SqM!^v
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); vu`,:/|h
//Utility.log(in.readLine()); siD/`T&
sHeader=httpConnection.getHeaderFieldKey(i); oE&#Tl?Vt
if(sHeader!=null) r;8X6C
{ q1,jDJglZ
if(sHeader.equals("Content-Length")) /Gvd5
{ ;}4^WzmK^(
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); UBM:.*wN
break; (!0fmL
} tl^![Z
} y28 e=i
else #pr{tL
break; y\zRv(T=
} -gVsOX0
} OpFm:j3
catch(IOException e){e.printStackTrace ();} rixt_}aE
catch(Exception e){e.printStackTrace ();} @h!nVf%fe
/7hC /!@
5?XIp6%x
Utility.log(nFileLength); o>Q=V0?
OtZc;c
i?B(I4a!G
return nFileLength; r"&VG2c0K
} @y(<4kLz
CC,CKb
DgODTxiX
//保存下载信息（文件指针位置） 4Bk9d\z
private void write_nPos() C(}N*e1
{ 'yNS(Bg=
try{ Zx 5Ue#I
output = new DataOutputStream(new FileOutputStream(tmpFile)); t>JPK_b0
output.writeInt(nStartPos.length); -;j '=?
for(int i=0;i<nStartPos.length;i++) 69$gPY'3
{ =p>IP"HJ
// output.writeLong(nPos); Sq[LwJ
output.writeLong(fileSplitterFetch.nStartPos); 9_xJT^10
output.writeLong(fileSplitterFetch.nEndPos); h Nx#x
} wAF<_NG#
output.close(); WnL7 A:sZ
} uO5y{O2W
catch(IOException e){e.printStackTrace ();} ayrCLv
catch(Exception e){e.printStackTrace ();} ;%!]C0?
} $HP<C>^Z8
VRD:PVz
]La~Bh6;m
//读取保存的下载信息（文件指针位置） '|@?R|i0
private void read_nPos() $$e"[g
{ GEtzLaq<
try{ M6XpauR-
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); \`Ow)t:
int nCount = input.readInt(); T':} p2}w+
nStartPos = new long[nCount]; PIM4c
nEndPos = new long[nCount]; % 9} ?*U
for(int i=0;i<nStartPos.length;i++) AI#.G7'O
{ "I0F"nQ
nStartPos = input.readLong(); XU|>SOR@z
nEndPos = input.readLong(); ~TYpq;rq
} PgdHH:v)
input.close(); 0F9p'_C
} D8f4X w}=
catch(IOException e){e.printStackTrace ();} si#1sdR
catch(Exception e){e.printStackTrace ();} D|D)782
} >b2wFo/em
S(PU"}vZy
v/x~L$[
private void processErrorCode(int nErrorCode) "wnN 0 p
{ /q5!p0fH*
System.err.println("Error Code : " + nErrorCode); ;}}k*< Z
} GS+Z(,J>=
J=6( 4>
"ifv1KZ#
//停止文件下载 C9^C4
public void siteStop() NM+(ss'
{ >>%E?'9A
bStop = true; c0QKx=
for(int i=0;i<nStartPos.length;i++) `Jn2(+
fileSplitterFetch.splitterStop(); A.cNOous|
Td5yRN! ?
$[V-M\q
} PnZY%+[I
} #AF.1;(k
//负责部分文件的抓取 _&e$?hY
**FileSplitterFetch.java 7'.]fs:
*/ ^NXxMC(e+
package NetFox; ]h%~'8g,
+;bP.[Z
B3&C=*y
import java.io.*; {ep.So6
import java.net.*; )4^Sz&\
S`pBEM
C_;A~iI7
public class FileSplitterFetch extends Thread { szGGw
Y(F>;/AA
4(&sw<k
String sURL; //File URL "2Q*-
long nStartPos; //File Snippet Start Position #+L:V&QE
long nEndPos; //File Snippet End Position ?H!QV;ku
int nThreadID; //Thread's ID e[Jh7r>'
boolean bDownOver = false; //Downing is over Y3O/`-9i
boolean bStop = false; //Stop identical rw.DKM'
FileAccessI fileAccessI = null; //File Access interface rIeOli:<
LC})aV|
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException nQ#NW8*Fs
{ ZoR6f\2M
this.sURL = sURL; 6e%ZNw{#=
this.nStartPos = nStart; =0mn6b9-=
this.nEndPos = nEnd; ?g4S51zpp
nThreadID = id; l7#2 e ORm
fileAccessI = new FileAccessI(sName,nStartPos);//定位 5xhYOwQBo
} R5=M{
6"yIk4u:
Y2$xlqQd"
public void run() `]F#j ]"
{ Y2}m/7aF
while(nStartPos < nEndPos && !bStop) /YHnt-}v,
{ q9(Z9$a(\
BHt9$$Z|
La$?/\Dv)
try{ BMb0Pu8
URL url = new URL(sURL); RV),E:?
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); xwojjiV
httpConnection.setRequestProperty("User-Agent","NetFox"); oZ>2Tt%
String sProperty = "bytes="+nStartPos+"-"; xu.TS
httpConnection.setRequestProperty("RANGE",sProperty); O% 8>siU
Utility.log(sProperty); @3`Pq2<
%xdyGAl:
WHcw5_3#
InputStream input = httpConnection.getInputStream(); g`dAj4B
//logResponseHead(httpConnection); W1ql[DqE{
bMGXx>x
H18pVh
byte[] b = new byte[1024]; t**MthnW
int nRead; w%$J<Z^-?
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) %ZX3:2
{ Ge1"+:tbJ
nStartPos += fileAccessI.write(b,0,nRead); 6|QIzs<Z-X
//if(nThreadID == 1) AbIYdFXB
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); MB+a?u0\
} 4e?MthJ>
NUh+ &M
?hKpJA'%
Utility.log("Thread " + nThreadID + " is over!"); ^*b11/7
bDownOver = true; *BKIA
//nPos = fileAccessI.write (b,0,nRead); |%uy{
} BK1I_/_!
catch(Exception e){e.printStackTrace ();} oj[<{/,C9
} C);I[H4Yfw
} @s0mX3P
^e--4B9|
%[on.Q'1]2
//打印回应的头信息 '#>(JN5\
public void logResponseHead(HttpURLConnection con) uQg&]bSv
{ A'n{K#
for(int i=1;;i++) WNSEc%
{ wZt2%+$6m
String header=con.getHeaderFieldKey(i); d$y?py
if(header!=null) {T3~js
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 7GRPPh<4
Utility.log(header+" : "+con.getHeaderField(header)); a}[rk*QmZ
else M/kBAxNIC|
break; iUlSRfrC$#
} ]{18-=
} x!fgZr{
Esf\Bo"
T=':$(t
public void splitterStop() (#nB90E{*
{ `!<#'PR
bStop = true; nZ[`Yrq)0
} 4xgfm.9I^
vw :&c.zd
=l>=]O~h
} VyWzb
n$<n Yr`X
6foiN W+
/* *RFBLCt
**FileAccess.java r-,u)zf"
*//文件访问(定位，写) *9(E0"
package NetFox; 3-BC4y/
import java.io.*; =d/$B!t{
S}6xkX
.:=5|0m
public class FileAccessI implements Serializable{ rN'}IS@5
\{={{O
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 w{ Pl
RandomAccessFile oSavedFile; av~kF
long nPos; cXK.^@du
p MR4]G
#lF 2qw
public FileAccessI() throws IOException WTu!/J<\
{ dte-2?%~j
this("",0); f |NXibmP
} V5p->X2#
IEY\l{s
czH# ~
public FileAccessI(String sName,long nPos) throws IOException XV1XzG#C
{ `Dp4Z>| K
oSavedFile = new RandomAccessFile(sName,"rw"); f& Vx`oj
this.nPos = nPos; 7,Y+FZ
oSavedFile.seek(nPos); 7V&ly{</
} nGxG!
T$Z}1e]
G)&!f)6
public synchronized int write(byte[] b,int nStart,int nLen) _po5j;"_O
{ rLA^ &P:
int n = -1; TjOK8 t
try{ rq:sy=;
oSavedFile.write(b,nStart,nLen); &;U F,
n = nLen; p,14'HS%@
} I7W?}bR*6
catch(IOException e) v.c.5@%%o
{ *S'?u_Y7
e.printStackTrace (); h$p}/A
} oz7=1;r
qoEZ>
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return n; tg7QX/KX
} _o==
TWdhl9Ot
A@e!~
} u/%Z0`X
a\KM^jrCD
"g5MltH
/* NT{'BJ
**SiteInfoBean.java izLB4pk$
*/ #)4p,H
package NetFox; S~M/!Xb
ps*iE=D
umt(e:3f5
public class SiteInfoBean { -/_hO$|W
vd/BO
8L[\(~Zf
private String sSiteURL; //Site's URL #4V->I
private String sFilePath; //Saved File's Path d}wE4(]b
private String sFileName; //Saved File's Name EjP)e;
private int nSplitter; //Count of Splited Downloading File (^m~UN2@~m
eF?jNO3
K6,d{n
public SiteInfoBean() !8tqYY?>@\
{//nSplitter的缺省值为5 VUD9ZyPw
//default value of nSplitter is 5 " s/ws
this("","","",5); &:~9'-O
} /*Gbl
d"S\j@
QV -ZP'e^
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) m?=J;r"Re
{ P`y.3aK
sSiteURL= sURL; (]-RL A>
sFilePath = sPath; ES)_X:\X?V
sFileName = sName; \"d\b><R
this.nSplitter = nSpiltter; uCgJF@
be [E^%
D8`SI21P
} Nj +^;Y
DIgur}q)@
A(z m
public String getSSiteURL() QiaBZAol
{ 7gREcL2
return sSiteURL; @B!gxW\C
} >^g\s]c[
.-1'#Z1T
oAvLSFn
public void setSSiteURL(String value) eTI?Mu>C
{ Ac\e>N
sSiteURL = value; lInf,Q7W
} i0~Af`v
$p*.[)
`2y?(BJp
public String getSFilePath() I")mg~f
{ 0Kg?X
return sFilePath; 6Q_ZP#oAV
} &td
f67t.6Vw2+
Su<>UsdUC
public void setSFilePath(String value) 0iKAg
{ xEufbFAN?
sFilePath = value; b`;Cm)@X!)
} GyfKSj;
O"wo&5b_
HIda%D
public String getSFileName() ?>My&yB
{ %0'7J@W
return sFileName; {D8yqO A}
} Ged} qXn
"oh;?gQ.
)!FheoR
public void setSFileName(String value) y s[z[
{ znAo]F9=J"
sFileName = value; SQ<{X/5
} B[d%?L_
F:AVik
z Ece>=C
public int getNSplitter() }taG/kE62
{ 7@&kPh}PG
return nSplitter; pk6<wAs*?#
} A>)Ced!
RQ4+EW1G
|gU)6}V@
public void setNSplitter(int nCount) CD4@0Z+
{ Z_mQpt|y
nSplitter = nCount; 24\^{3nOK
} cI-@nV
} *DvQnj
#VsS C1
1/%5pb2\
/* onm"7JsO'
**Utility.java Ql"~ z^L
*/ CtZOIx.;|
package NetFox; \5j#ad
#$l:%
-]G=Q1 1
public class Utility { X2{Aa T*M
)[ejb?{d
8[#EC3
public Utility() TgKSE1
{ V;hO1xfR3&
Uy@:-NC)kn
z`,dEGfh^
} un}!&*+
D'#,%4P,e\
//线程睡眠 `rV-,-r@
public static void sleep(int nSecond) ^?|d< J:{
{ U|8?$/*\
try{ |o@U L
Thread.sleep(nSecond); 7Dw.9EQ
} SAE'y2B*
catch(Exception e) z'\BZ5riX<
{ j|{ n?
e.printStackTrace (); 5Ha(i [d
} $"va8,
} yh'*eli
^2i$AM1t
//日志 AYDAt5K_
public static void log(String sMsg) }|)T<|Y;
{ *\*]:BIe&v
System.err.println(sMsg); `/<f([w
} hsJGly5H
)~IOsTjI
X_)x Fg'k
public static void log(int sMsg) >)k[085t
{ ""IPaNHQ
System.err.println(sMsg); w=^~M[%w
} )(pgJLW
} L]l?_#*x
]ZH6 .@|
HcrlcxwM\i
/* 4\j1+&W
**TestMethod.java 1B$8<NCQ=?
*/ mRN[lj
package NetFox; # wyjb:Ql
[}4\CWM
l-5O5|C
public class TestMethod { rl-#Ez
cfy9wD
]hRs -x
public TestMethod() L@J$kqWY
{ ///xx/weblogic60b2_win.exe _qH]OSo
try{ @c}Gw;e
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); iF_u/#
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); YoZd,} i
SiteFileFetch fileFetch = new SiteFileFetch(bean); C~PP}|<~V
fileFetch.start(); %&J`mq
} #%{
catch(Exception e){e.printStackTrace ();} _>^Y0C[?5
BM5)SgK
~+PKWs'}F
} lB7/oa1]>
iz+,,UH
}4Q3S1|U
public static void main(String[] args) v!=e]w6{
{ Z1p%6f`
new TestMethod(); w9Nk8OsL
} &SPIu,
} M #%V%<
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