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)); h1*FPsc
} 5VZjDg?
for(int i=0;i<nEndPos.length-1;i++) 7DZTQUb"
{ nd.hHQ
nEndPos = nStartPos[i+1]; 7 OWsHlU
} # M>wH`Q#
nEndPos[nEndPos.length-1] = nFileLength; ,_bp)-OG
} xh r[A
} }#bZ8tm&
GMw)*
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//启动子线程 &oEyixe
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; fbV@=(y?
for(int i=0;i<nStartPos.length;i++) ]'g:B p
{ @k9Pz<ub
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 7f r>ZY^
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 0MrN:M2B
nStartPos,nEndPos,i); (0}j]p'w
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); #D0 ~{H
fileSplitterFetch.start(); `O n(v
} G1[(F`t>
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), B!uxs
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); He<;4?:
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", +q-c8z
nEndPos = " + nFileLength); ]!faA\1
// fileSplitterFetch[nPos.length-1].start(); LQ>$>A(
`S$sQ&
t\%%d)d9
//等待子线程结束 . pP7"E4]
//int count = 0; ,cD1{T\
//是否结束while循环 5k~\or 5_
boolean breakWhile = false; m9!DOL1pl
!5~k:1=
x_W3sS]ej
while(!bStop) N<n8'XDdG
{ 4 4`WYK l
write_nPos(); |]tZ hI"3<
Utility.sleep(500); &F`L}#oL&
breakWhile = true; y!5:dvt
N iISJWk6'
`;/XK,m-
for(int i=0;i<nStartPos.length;i++) uY]T:UVk
{ ]5)"gL%H`
if(!fileSplitterFetch.bDownOver) .<.#aY;N
{ lRH0)5`
breakWhile = false; Bq{]Eh0%
break; [4\aYB9N
} u>}zm_
} t)'dF*L
if(breakWhile) nALnB1
break; 7UDq/:}Fo
4m\([EO
DJ|BM+
//count++; OfJd/D
//if(count>4) jzMg'z/@J
// siteStop(); v#F-<?Vv
} 3a^)u-9,x
mw"}8y
}<&d]N
System.err.println("文件下载结束！"); x=vK EyS@
} BUDGyl/=
catch(Exception e){e.printStackTrace ();} X|Dpt2A=
} 0e\y~#-
j/' g$
s>r ^r%uK
//获得文件长度 QoWR@u6a
public long getFileSize() Y$+QNi
{ )ji@k(x27q
int nFileLength = -1; 6Hl<,(vn
try{ o?y"]RCM
URL url = new URL(siteInfoBean.getSSiteURL()); :~erh}~ps
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); gCL{Cw
httpConnection.setRequestProperty("User-Agent","NetFox"); <r3Jf}%tT
W #47Cz
y+RRg[6|
int responseCode=httpConnection.getResponseCode(); 69iM0X!'u
if(responseCode>=400) ,(;5%+#n
{ fB7ljg
processErrorCode(responseCode); YuA7r"c
return -2; //-2 represent access is error ^}@`!ON
} ])=H
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%",ULtZ+
String sHeader; ]zcV]Qj$~
C#h76fpH
lz}llLb1
for(int i=1;;i++) Pa[?L:E
{ !-ZP*V3}h
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); 1@@y]s_.a
//Utility.log(in.readLine()); zWtj|%ts
sHeader=httpConnection.getHeaderFieldKey(i); 9cz)f\
if(sHeader!=null) zuMO1s
{ @.1Qs`pt
if(sHeader.equals("Content-Length")) >]-<uT_
{ p7$3`t6u
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); )tvc/)&A}
break; _0m}z%rI
} F^]aC98]1
} !?6.!2
else qsTq*G
break; "vsjen.K>
} V(DjF=8
} F^xaz^=`u
catch(IOException e){e.printStackTrace ();} R}hlDJ/m-
catch(Exception e){e.printStackTrace ();} 0JyqCbl
l@#b;M/
K#@K"N=
Utility.log(nFileLength); r_q~'r35_
F "!`X#
z1FL8=
return nFileLength; Bd8hJA
} nSS}%&a:LX
GRy4cb2
O'fc/cvh='
//保存下载信息（文件指针位置） C[g&F0 6
private void write_nPos() soDfi-2o3
{ Yx!n*+:J
try{ s<,"Hsh^CR
output = new DataOutputStream(new FileOutputStream(tmpFile)); QU,?}w'?d
output.writeInt(nStartPos.length); %uW<
for(int i=0;i<nStartPos.length;i++) =/m}rcDN
{ PYaOH_X.
// output.writeLong(nPos); }^Z< dbt
output.writeLong(fileSplitterFetch.nStartPos); t:disL&!E
output.writeLong(fileSplitterFetch.nEndPos); 6kC)\uy
} `u$24h'!
output.close(); A>5S]
} f)WPOTEY
catch(IOException e){e.printStackTrace ();} kHZKj!!R
catch(Exception e){e.printStackTrace ();} so'eZ"A:
} aC4m{F[
pIL`WE1'
ijg,'a~3E
//读取保存的下载信息（文件指针位置） hl}dgp((
private void read_nPos() [-QK$~[ g
{ x7Eeb!s0f,
try{ noFh p
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); WVj&0
int nCount = input.readInt(); ^T=5zqRD
nStartPos = new long[nCount]; bnIf}ut-G
nEndPos = new long[nCount]; ,I=O"z>9
for(int i=0;i<nStartPos.length;i++) oUCVd}wH
{ :%pw`b, =V
nStartPos = input.readLong(); [&fWF~D-p<
nEndPos = input.readLong(); =g1D;
} 1/!nV
input.close(); Qve`k<Cj"
} K:C+/O
catch(IOException e){e.printStackTrace ();} b\H/-7<
catch(Exception e){e.printStackTrace ();} /oBK&r[(
} H_v/}DEG
gr[D!D>
i;gw=Be
private void processErrorCode(int nErrorCode) ;wfH^2HxE)
{ :LG}yq^
System.err.println("Error Code : " + nErrorCode); YK7gd|LR]
} Ed4_<:
5QNBB|X@
S".owe$\
//停止文件下载 A-}PpH~.Z
public void siteStop() +ESX.Vel
{ CRP7U
bStop = true; [@jp9D H
for(int i=0;i<nStartPos.length;i++) i_'|:Uy*F
fileSplitterFetch.splitterStop(); !N@Yh"c
^a: Saq-}
ikeJDKSG
} X+fuhcn
} K%o6hBlk_
//负责部分文件的抓取 T "ZQPLg
**FileSplitterFetch.java @DRfNJ}
*/ \3,$YlG
package NetFox; %jYQ
8.6no
9N`+ O
import java.io.*; Z1E`I89<
import java.net.*; Q3'(f9 x
] `b<"
[J(@$Qix
public class FileSplitterFetch extends Thread { o%y+Y;|?J
bL6L-S
|E>v~qD8I
String sURL; //File URL ;))[P_$zB
long nStartPos; //File Snippet Start Position dfYYyE
long nEndPos; //File Snippet End Position h'z+8X_t
int nThreadID; //Thread's ID OLhWkN,qA
boolean bDownOver = false; //Downing is over v)X[gt tf
boolean bStop = false; //Stop identical +-xSuR,
FileAccessI fileAccessI = null; //File Access interface '` BjRg57]
A?%XO %
TW;|G'}$
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException `Pz!SJ|
{ 5pN08+
this.sURL = sURL; Off: ~
this.nStartPos = nStart; E1mI Xd;.
this.nEndPos = nEnd; A=\'r<:
nThreadID = id; Ep#<$6>
fileAccessI = new FileAccessI(sName,nStartPos);//定位 p0%6@_FT~
} 4DG 9`5.
A,-[/Z K/
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public void run() sYW1T @
{ 4okHAv8;
while(nStartPos < nEndPos && !bStop) LrmtPnL
{ dT*f-W
8 RzF].)
v ](G?L9b
try{ |TNiKy
URL url = new URL(sURL); &Nj:XX;X
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); Gx~"iM
httpConnection.setRequestProperty("User-Agent","NetFox"); Cv?<}q
String sProperty = "bytes="+nStartPos+"-"; +qu@dU0\`|
httpConnection.setRequestProperty("RANGE",sProperty); x _YV{
Utility.log(sProperty); 9/8@
[5}cU{M
wd2P/y42;;
InputStream input = httpConnection.getInputStream(); W? 6
//logResponseHead(httpConnection); @5dBb+0J
A1=$kzw{UH
[xp~@5r'
byte[] b = new byte[1024]; <*b]JY V@
int nRead; iPtm@f,bI
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) CU7iva
{ j|VlHDqR
nStartPos += fileAccessI.write(b,0,nRead); eX]9mQ]E
//if(nThreadID == 1) ,&O:/|c E
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); T^-H_|/M
} ,i$(yx?
2yQ;lQ`
nFf\tf%8
Utility.log("Thread " + nThreadID + " is over!"); Sf.8Ibw
bDownOver = true; T{v<
//nPos = fileAccessI.write (b,0,nRead); 9 up*g
} HCe-]nMd
catch(Exception e){e.printStackTrace ();} o+6^|RP
} J T0,Z
} !@]h@MC$7
K_w0+oY a
*6\`A!C
//打印回应的头信息 3ec==.
public void logResponseHead(HttpURLConnection con) Nsy9 h}+A
{ z?b(|f\!
for(int i=1;;i++) d/-]y:`f`
{ sL[(cX?;2
String header=con.getHeaderFieldKey(i); aS1P]&
if(header!=null) >x_:=%Wr+
//responseHeaders.put(header,httpConnection.getHeaderField(header)); G3^n_]Jb
Utility.log(header+" : "+con.getHeaderField(header)); 2=UTH%1D
else tr67ofld|
break; /i]=ndAk
} F6neG~Y
} %(wsGNd
dA MilTo
7HR%rO?'
public void splitterStop() Kw5+4R(5
{ *F4G qX3
bStop = true; 6u]OXPA|
} 80l3.z,:
vCH v
(/rIodHJO
} 3 v,ae7$U&
F" #3s=
ju2X*
/* L^ jC& dF
**FileAccess.java X:} 5L>'
*//文件访问(定位，写) SJ|.% gn
package NetFox; 5IF~]5s
import java.io.*; BX)cV
6[Pr<4J
1wH/#K
public class FileAccessI implements Serializable{ HU.6L'H*
Ul~}@^m]4}
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 Ivgwm6M
RandomAccessFile oSavedFile; V44sNi
long nPos; J Wyoh|
P A+e= %
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public FileAccessI() throws IOException gV.Pg[[1
{ 4>ce,*B1
this("",0); ]V]@Zna@g
} ~6kA<(x
pQm!Bt L
]C:Ifh~
public FileAccessI(String sName,long nPos) throws IOException 0R!}}*Ee>q
{ gu%'M:Xe
oSavedFile = new RandomAccessFile(sName,"rw"); /n3&e
this.nPos = nPos; 0o'ML""j
oSavedFile.seek(nPos); Jtk.v49Ad>
} f`";Q/rG
+`vZg^_c`
qZ]VS/5A
public synchronized int write(byte[] b,int nStart,int nLen) / )u,Oa
{ Q8/0Cb/
int n = -1; D@vvy6>~s
try{ ';L^mxh
oSavedFile.write(b,nStart,nLen); LyPBFo[?
n = nLen; ?Dp^dR
} |h~/Zz=
catch(IOException e) RlPByG5K
{ a0W\?
e.printStackTrace (); arH\QPaka'
} J,M5<s[Xqt
oP`M\KXau
I z=w2\r
return n; Xs,PT
} F>-@LOqHy
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FoXQ]X7"
} *L8HC8IbH
HkB<RsS$p_
C- Rie[
/* }c#/1J7
**SiteInfoBean.java 9TN5|x
*/ ML"P"&~u6
package NetFox; f?I *`~k
&``oZvuB
Jt, 4@
public class SiteInfoBean { s=@CeV@4W
Ewsg&CCN
E&tmWOMj>
private String sSiteURL; //Site's URL DWxh{h">
private String sFilePath; //Saved File's Path } K-[/;
private String sFileName; //Saved File's Name pPoC61F
private int nSplitter; //Count of Splited Downloading File Z!l!3(<G.f
2}C>{*}yQ
J0W).mD_H
public SiteInfoBean() Ck a]F2,
{//nSplitter的缺省值为5 c89vx 9
//default value of nSplitter is 5 L;t~rW!1
this("","","",5); "LaX_0t)
} 29DWRJU
X',0MBQ0
q _|5,_a
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) ?v~3zHK
{ *pUV-^uo
sSiteURL= sURL; xVX||rrh
sFilePath = sPath; ^aWNtY' :
sFileName = sName; nL20}"$E
this.nSplitter = nSpiltter; O;t?@!_
D)Rf
0lh6b3tdP
} yC*BOJS
1)r_h(
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public String getSSiteURL() cyeDZ)
{ zFQkUgb
return sSiteURL; Y rnqi-P
} |^{" 2l"j
/\I%)B47^9
l#.,wOO{
public void setSSiteURL(String value) RteTz_z{
{ r@UY$z
sSiteURL = value; M.^A`
} `bF;Ew;
2![W N*N>O
&bK$!8Z
public String getSFilePath() rM.<Gi05Qe
{ cHct|Z u
return sFilePath; *lF%8k"Al
} 3(p6ak2lv
Q8:ocEhR
o_m.MMEU
public void setSFilePath(String value) x}j41E}
{ ^i1:PlW]
sFilePath = value; dph6aN(49
} *lO+^\HXD
TBT*j&!L
DQnWLC"u
public String getSFileName() !\4FIs&Qv
{ Pk_{{Z(1o
return sFileName; J :(\o=5 5
} YcZ4y@6"
MX\-)e#
W/Q%%)J
public void setSFileName(String value) N)Kr4GC
{ @ xr
sFileName = value; 4 Z)]Cq*3
} XnOl*#P
U# B
R/|{?:r?:x
public int getNSplitter() AE _~DZ:%c
{ HE'8
return nSplitter; y@JYkp>I
} XjU;oh4:.
>L4$DKO
/MtacR
public void setNSplitter(int nCount) ^SCWT\E
{ )zV5KC{{
nSplitter = nCount; FR"^?z?}p
} Xy&#}S}9
} $c47cJO)W
[.,6~=}vP
-y<uAI g
/* 4gENV{L
**Utility.java x0GZ2*vfsb
*/ e84TLU?~
package NetFox; DL_\luh
Ts6X:D4,
czRh.kz,
public class Utility { AFED YRX
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&N;6G`3
public Utility() 4*W7{MPY
{ 4iW2hV@m
[_@OCiV5)
bnQO}G
} .5xg;Qg\Y
*JXJ 2
//线程睡眠 P s;:g0
public static void sleep(int nSecond) k3XtKPO
{ g2q=&eI"
try{ =p6xc}N
Thread.sleep(nSecond); (J*0/7 eX
} cqp#1oM4M
catch(Exception e) ]plC
{ RoZV6U~
e.printStackTrace (); JM%#L*;
} +dv@N3GV
} _: K\v8
CG;D(AWR;
//日志 A>puk2s
public static void log(String sMsg) .YRSd
{ ,L G&sa"
System.err.println(sMsg); swrd
} M-gjS6c\3
8>9+w/DL
Ui&$/%Z|
public static void log(int sMsg) X;NTz75
{ %Z4=3?5B"9
System.err.println(sMsg); ~T~v*'_h
} #v-!GK_<
} ./'n2$^3
!TFVBK
IpxjP\
/* kZNZ?A<D
**TestMethod.java b&1@rE-
*/ S)%x22sqf
package NetFox; t/g}cR^Q
(1^(V)@
X'm2uOEj
public class TestMethod { x?IT#ty
*&D=]fG
9':$!Eoq
public TestMethod() T2{+fRvN
{ ///xx/weblogic60b2_win.exe KX`,7-
try{ e j9G[
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); |.A>0-']M
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); ?H&p zY~H
SiteFileFetch fileFetch = new SiteFileFetch(bean); `O/)q^m1L
fileFetch.start(); L/I-(08!Y:
} 0bE_iu>f'
catch(Exception e){e.printStackTrace ();} _f`m/l
nq=fSK(
YaU A}0cW
} 6_Kz}PQ
q}jf&xUWzH
bBX~ZWw
public static void main(String[] args) jVz1`\Nje
{ '<Gqu_-
new TestMethod(); @j6D#./7j
} Ar==@777j
} xph60T
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