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)); LKY4rY!|@d
} 2;.7c+r0
for(int i=0;i<nEndPos.length-1;i++) D8slSX`6j
{ 6d"dJV.\
nEndPos = nStartPos[i+1]; 8m1@l$
} ^dH#n~Wx0
nEndPos[nEndPos.length-1] = nFileLength; 9ET2uDZpL
} Wfkm'BnV
} Lhu2;F\/
1eI>Yy>}
\tLJ( <8
//启动子线程 GEfX,9LF&
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; KbVV[ *
for(int i=0;i<nStartPos.length;i++) y!GjC]/
{ *ghkw9/
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Zu:cF+hl
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), Ta?#o
nStartPos,nEndPos,i); t*y4)I !gR
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 2fTkHBhn&
fileSplitterFetch.start(); +pc_KR
} ]oP2T:A
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), 3Gf^IV-
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); yAR''>
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", +jO1?:Lr
nEndPos = " + nFileLength); eV^@kI4
// fileSplitterFetch[nPos.length-1].start(); 6%C:k,Cx{d
Ki}PO`s
RfDIwkpp
//等待子线程结束 1K^blOLXe
//int count = 0; `rW{zQYM
//是否结束while循环 kmNY ;b6Y$
boolean breakWhile = false; hE-`N,i}
9c8zH{T_{
|M`B
while(!bStop) jJ?MT#v
{ IV;juFw}G
write_nPos(); ?(>7v[=iT
Utility.sleep(500); _)p@;vGV
breakWhile = true; f( hK>H
T,Cq;|g5E
6Bmv1n[X^h
for(int i=0;i<nStartPos.length;i++) a+)Yk8%KY
{ Usk@{
if(!fileSplitterFetch.bDownOver) pK1P-!c
{ f'\I52;FB
breakWhile = false; 5|NM]8^^0[
break; LPb43
} k7>*fQ89@
} B{H;3{0
if(breakWhile) R}llj$?
break; BRG1/f d
- 4'yp
I?J$";A
//count++; wWY6DQQB
//if(count>4) D(Zux8l
// siteStop(); })T}e7>T
} Ig"Krz
"'94E,W
}C"EkT!F
System.err.println("文件下载结束！"); SEr\ u#
} kWjCSC>jA
catch(Exception e){e.printStackTrace ();} (NOAHV0H
} [X#bDO<t
{G&K_~Vj
]n${j/x
//获得文件长度 '1~mnmiP
public long getFileSize() !ceuljd]
{ uh\I'
int nFileLength = -1; r&A#h;EQX2
try{ D`3}j
URL url = new URL(siteInfoBean.getSSiteURL()); aN).G1
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); W!4GL>9m}A
httpConnection.setRequestProperty("User-Agent","NetFox"); ']u w,b
v#IW;Rj8
Os*,@N3t
int responseCode=httpConnection.getResponseCode(); L'J$jB5cP
if(responseCode>=400) szF[LRb
{ c;Hf+n
processErrorCode(responseCode); MkC25
return -2; //-2 represent access is error ?:s`}b
} /_xwHiA
G<4H~1?P
%3KWc-
String sHeader; ]Q-ON&/
-869$
ul(1)q^
for(int i=1;;i++) (jPN+yQ
{ j()_ VoB1
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); zY(w`Hm2
//Utility.log(in.readLine()); Fq&@dxN3
sHeader=httpConnection.getHeaderFieldKey(i); 1e'-rm F
if(sHeader!=null) ym2\o_^(
{ rxI?|}4
if(sHeader.equals("Content-Length")) fH`P8?](x
{ 2xni! *T+
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); `;(/Wh
break; Um9!<G=;
} y{? 6U>_
} |LcN_,}6
else v8y77:
break; 5[al^'y
} d}>Nl$
} HOsq _)K
catch(IOException e){e.printStackTrace ();} :?RooJ~#
catch(Exception e){e.printStackTrace ();} |}QDC/
.J%}ROm
cI?dvfU?
Utility.log(nFileLength); 6}L[7~1
:&2RV_$>=
:QUZ7^u
return nFileLength; UI<'T3b
} MGX,JW>L
[@rZ.Hsl
HzQ6KYAMq
//保存下载信息（文件指针位置） kR-N9|>i
private void write_nPos() _Y|k \|'
{ yHCQY4/
try{ RT)0I;
output = new DataOutputStream(new FileOutputStream(tmpFile)); W5 fO1F
output.writeInt(nStartPos.length); G&/}P$
for(int i=0;i<nStartPos.length;i++) nvu|V3B0
{ q}ZZqYk
// output.writeLong(nPos); P;MS%32
output.writeLong(fileSplitterFetch.nStartPos); uEVRk9nb
output.writeLong(fileSplitterFetch.nEndPos); qk~QcVg
} ^5 F-7R8Q
output.close(); 9C|T/+R
} z\_q`43U7
catch(IOException e){e.printStackTrace ();} 7Q0M3m
catch(Exception e){e.printStackTrace ();} E0ud<'3<
} Ca@[]-_H
p tv
WYRTt2(+%
//读取保存的下载信息（文件指针位置） &5(|a"5+G
private void read_nPos() Ea!}r|~]0
{ asQ pVP
try{ : 60PO
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); u5V<f;
int nCount = input.readInt(); baR{
nStartPos = new long[nCount]; S &s7]
nEndPos = new long[nCount]; r$k *:A$%
for(int i=0;i<nStartPos.length;i++) |rW}s+Kcr
{ JF: QQ\
nStartPos = input.readLong(); n_$lRX5
nEndPos = input.readLong(); LP@Q8{'
} 9@QP?=\Y
input.close(); nLto=tNUO
} |oSyyDYWP
catch(IOException e){e.printStackTrace ();} v :6`(5
catch(Exception e){e.printStackTrace ();} *r:8=^C7S
} y"e'Gg2
4)JrOe&k
MyCX6+Ci)
private void processErrorCode(int nErrorCode) 9S=9m[#y'
{ ^CZn<$
System.err.println("Error Code : " + nErrorCode); [g=yuVXNZZ
} nHD4J;l
&1]}^/u2
~S"G~a(&j
//停止文件下载 swi|
public void siteStop() K`(STvtM
{ )P:TVe9`
bStop = true; J^n(WnM*F
for(int i=0;i<nStartPos.length;i++) kn+`2-0
fileSplitterFetch.splitterStop(); 5y}}?6n+
7k+UCiu>
)w;XicT
} #jA|04w
} 6D{|!i|r4
//负责部分文件的抓取 L)8;96
**FileSplitterFetch.java lG%oqxJ+ L
*/ )3h=V^rm
package NetFox; Uk|Xs~@#E
{r[*}Bv
sKn>K/4JZ
import java.io.*; ^4B6IF*
import java.net.*; :ozHuHJ#
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F~W*"i+EZ
public class FileSplitterFetch extends Thread { #^!oP$>1
(zk'i13#6
Pa0tf:
String sURL; //File URL >/5D/}4
long nStartPos; //File Snippet Start Position .LnXKRd{
long nEndPos; //File Snippet End Position S U2`H7C*
int nThreadID; //Thread's ID "^22Y}VB
boolean bDownOver = false; //Downing is over =J0FT2 d
boolean bStop = false; //Stop identical #mx;t3ja7
FileAccessI fileAccessI = null; //File Access interface Gp@Y=mU
Gxm+5q
[gIStKe
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException akJ{-
{ +;FF0_
this.sURL = sURL; 6S"bW)O
this.nStartPos = nStart; !Aunwq^
this.nEndPos = nEnd; L_)?5IOJ$
nThreadID = id; yq6!8OkF
fileAccessI = new FileAccessI(sName,nStartPos);//定位 W%0-SR
} 3w!oJB
7D9R^\K
oUltr
public void run() /\ ~{
{ ~NU~jmT2
while(nStartPos < nEndPos && !bStop) w>/KQ> \"
{ cpu+"/\
<0v'IHlZ8
4zJ9bF4
try{ iO<O2A.F
URL url = new URL(sURL); "i_tO+
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); D!qtb6<.
httpConnection.setRequestProperty("User-Agent","NetFox"); RDzL@xCcn
String sProperty = "bytes="+nStartPos+"-"; -lb}}z+/
httpConnection.setRequestProperty("RANGE",sProperty); Og30&a!~F
Utility.log(sProperty); mc!3FJ
9FPl
Srol0D I
InputStream input = httpConnection.getInputStream(); dn%/SJC
//logResponseHead(httpConnection); I0Wn?Qq=@
LT'#0dCC
Pvbw>k;
byte[] b = new byte[1024]; e|+uLbN&;c
int nRead; d{ OY
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) "UVV/&`o
{ Jv7 @[<$
nStartPos += fileAccessI.write(b,0,nRead); DU}q4u@)
//if(nThreadID == 1) sI*( MhU
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); :*}tkr4&eh
} e5veq!*C?
='soSnT
.JQR5R |Q
Utility.log("Thread " + nThreadID + " is over!"); _ogT(uYyr
bDownOver = true; $JX_e
//nPos = fileAccessI.write (b,0,nRead); J8/>b{Y
} 0FEb[+N
catch(Exception e){e.printStackTrace ();} Hej0l^
} dQ;rO$co
} 9;h1;9sC|
^0X86
3@6f%Dyj
//打印回应的头信息 @jwUH8g1
public void logResponseHead(HttpURLConnection con) 6 D!,vu
{ ;]<$p[m
for(int i=1;;i++) mRQ F5W6
{ .0\Wu+
String header=con.getHeaderFieldKey(i); y6:=2(]w<p
if(header!=null) `@Kh>K
//responseHeaders.put(header,httpConnection.getHeaderField(header)); {/#?n["
Utility.log(header+" : "+con.getHeaderField(header)); tk1qgjE(?
else |mmIu_
break; 3y 0`G8P'h
} ?*}V>h 8m)
} W&+UF'F2
]IyC
-*?a*q/#nQ
public void splitterStop() $lV0TCgba8
{ 7F+w o
bStop = true; >@ge[MuS
} tYmWze.j
C7qbofoV
}>)"!p;t_
} `' 6]Z*
Y\9uR!0
Gi;eDrgj~
/* >@TZYdl
**FileAccess.java E;-R<X5n
*//文件访问(定位，写) T(3"bS.,
package NetFox; 2v%~KV
import java.io.*; S=M$g#X`5
w6#hsRq[C
i~l0XjQbs
public class FileAccessI implements Serializable{ fE_QB=9 cz
`wk#5[Y_
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 C/ ;f)k<
RandomAccessFile oSavedFile; ,v)@&1Wh:
long nPos; p^~lQ8t
KY4|C05,
m=j7 vb
public FileAccessI() throws IOException +s_@964
{ \Sg&Qv`
this("",0); s*(Y<Ap7d
} my*UN_]
.c~;/@{
6,s@>8n
public FileAccessI(String sName,long nPos) throws IOException ogjm6;
{ N}\$i&Vi
oSavedFile = new RandomAccessFile(sName,"rw"); VA2%2g2n{
this.nPos = nPos; \{NeDv{A
oSavedFile.seek(nPos); #7gOtP#{
} [ &R-YQ@
WWq)CwR
w*Kw#m'U
public synchronized int write(byte[] b,int nStart,int nLen) ;:"~utL7
{ f9OVylm
int n = -1; oPre$YT}h
try{ 6RzTSb
oSavedFile.write(b,nStart,nLen); Zf(ucAhL
n = nLen; %2/WyD$U
} f+L )x
catch(IOException e) B.{0,bW?
{ VWbgusxJ
e.printStackTrace (); 80:na7$)#
} $,'r} %
b/ ~&M+)
#pOW2 Uj8\
return n; H(n_g QAX
} uXK$5"
t{x&|%u
G0a UZCw
} |@V<}2zCZ
kk^KaD4dA
&b{L|I'KYT
/* JX>_imo
**SiteInfoBean.java #gi&pR'$
*/ ZTHrjW1
package NetFox; =Z%&jul
?vM{9!M
<3ovCqa
public class SiteInfoBean { O:k@'&
TLO-$>h
MUVp8!*@
private String sSiteURL; //Site's URL /UM9g+Bb
private String sFilePath; //Saved File's Path //|9J(B]
private String sFileName; //Saved File's Name +gK7`:v4O*
private int nSplitter; //Count of Splited Downloading File %Z.>)R4
[R& P.E7w'
X8?|5$Ey
public SiteInfoBean() ]Alu~Dw
{//nSplitter的缺省值为5 [Zgy,j\\
//default value of nSplitter is 5 &5C%5C~ch
this("","","",5); I,t 0X)
} 8Ck:c45v
fZXd<Fg+
N=:yl/M
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) GawLQst[+
{ 1~ZDHfd5
sSiteURL= sURL; Q_M2!qj
sFilePath = sPath; P_Po g^
sFileName = sName; B/pNM81(
this.nSplitter = nSpiltter; hLJO\=0rJz
W6~<7
&X +@,!
} J& yDX>
:i?Z1x1`
b!_l(2
public String getSSiteURL() Y5Ey%Mm6
{ ZhM-F0;`
return sSiteURL; ?CM,k0
} gY;N>Yq,C
0D0#*J
9Q].cDe[
public void setSSiteURL(String value) yvNYYp2r
{ VJuPC
sSiteURL = value; `4l>%S8y:
} cCWOGd
;41s&~eR
("mW=Ln
public String getSFilePath() _czLKbcF
{ H${Ym BG
return sFilePath; c3oI\lU
} OJkPlDym
0qJ 3@d
_v]I6<!5U
public void setSFilePath(String value) &tp5y}=n
{ Wpj.G
sFilePath = value; "P0o)g+{
} yf_<o
0@3g'TGl
w_A-:S 5C
public String getSFileName() t}NxD`8
{ bFJmXx&
return sFileName; {jlm]<:&Z
} o&I0*~sN
=U|J{^ >I
zIRa%%.i<
public void setSFileName(String value) <J`_Qc8C
{ zse!t
sFileName = value; 0Dh a1[=
} unjo&
G++kUo<
]l+2Ca:-[j
public int getNSplitter() X,T^(p
{ MQ,$'Y5~H
return nSplitter; XXe7w3x{
} 2LD4f[a;
_k6N(c2Nd
HjnHl-
public void setNSplitter(int nCount) zU1rjhv+
{ f_;3|i
nSplitter = nCount; T5Pc2R
} 4.??U!r>KI
} ~zYp(#0op
73N%_8DH
xx/DD%IZ
/* 1 4(?mM3
**Utility.java |fRajuA;
*/ Vvv -f
package NetFox; QKHmOVh]
Qj3UO]>
sU+~#K$b
public class Utility { 5{cAawU.
.dM 0
p4aM`PW8>=
public Utility() j}h50*6KO
{ mP:mzmUw
@6t3Us~/
$,6=.YuY
} Zvr(c|Q
u&pLF%'EQ
//线程睡眠 :%!SzI?
public static void sleep(int nSecond) >1joCG~
{ sy>Pn
try{ 3c-ve$8u~
Thread.sleep(nSecond); M_*w)<
} drb_GT
catch(Exception e) kMwt&6wS
{ ",~3&wx
e.printStackTrace (); %e1<N8E4
} R@"N{ [9
} &s] s]V)
>n` OLHg;
//日志 iB]kn(2C
public static void log(String sMsg) .cu5h
{ nq6]?ZJ
System.err.println(sMsg); %*jpQOw
} [Q^kO;
IM +Dm
e3(0L I
public static void log(int sMsg) &4{%3w_/
{ 4J I;NN
System.err.println(sMsg); 0Fi7|
} Sb,{+Wk
} +mF}j=k
T /]ayc:
\Dt0 } ?;k
/* YY]LK%-
**TestMethod.java "BzRLg!J
*/ # ^%'*/z
package NetFox; 5[Q44$a{
<|m"Q!f
kdoE)C
public class TestMethod { IE,g
_L: /2
LW2Sko?Yo
public TestMethod() 1) @Wcc.
{ ///xx/weblogic60b2_win.exe [&Qrk8EN
try{ 'nCBLc8
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); y"){?
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); g5Hs=c5=\
SiteFileFetch fileFetch = new SiteFileFetch(bean); M8g=t[\
fileFetch.start(); Ay2|@1e
} vn kktD'n
catch(Exception e){e.printStackTrace ();} dXdU4YJX
31bKgU{
#}B~V3UD
} b$B5sKQ
\x|(`;{
2 3>lE}^G
public static void main(String[] args) ~xXB !K~C
{ H9 't;Do
new TestMethod(); np)-Yzr
} 4q~l?*S
} %K/rPhU
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