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)); ]MTbW=*}ED
} 5g ;ac~g
for(int i=0;i<nEndPos.length-1;i++) /VTM 9)u
{ 8v92Ng7
nEndPos = nStartPos[i+1]; [rYT
} &#m"/g7w4N
nEndPos[nEndPos.length-1] = nFileLength; 2#5,MP~r
} tj1JB%
} E^Gg '1
`,Vv["^PB
<vc`^Q&4B
//启动子线程 #Gf+=G
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; M8;lLcgu.
for(int i=0;i<nStartPos.length;i++) xFFr
{ 3Rv7Qx
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), {rH9grb
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), HZ"Evl|n
nStartPos,nEndPos,i); kODK@w V-
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 8Jr?ZDf`
fileSplitterFetch.start(); d^Di*&X
} LXfCmc9|Z
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), pa]"iZz
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 5z/Er".P
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", i%{X9!*%TX
nEndPos = " + nFileLength); sq0 PBEqq
// fileSplitterFetch[nPos.length-1].start(); ]]iPEm"@
L2z2}U=<
9@VO+E$7L
//等待子线程结束 P9Q2gVGAO{
//int count = 0; (!K_Fy@
//是否结束while循环 ^>$P)=O:v
boolean breakWhile = false; ^HA %q8| n
U9d:@9Y
oR#:NtX@
while(!bStop) H=MCjh&$q
{ %b!-~ Y.
write_nPos(); le>Wm&E
Utility.sleep(500); )M<vAUF
breakWhile = true; $&P?l=UG
MBr:?PE7
{bNXedZ\
for(int i=0;i<nStartPos.length;i++) ]`=X'fED
{ S01wwZ
if(!fileSplitterFetch.bDownOver) h5zVGr
{ %"$@%"8;3
breakWhile = false; -e@!
break; )9nElb2
} !Jfs?Hy
} \l#>dq"Y
if(breakWhile) *wbZ;rfF
break; sKaE-sbJY
W 0[N0c
/\d$/~BFi
//count++; $a;]_Y
//if(count>4) xyHejE}
// siteStop(); adEJk
} q }C+tn"\
\>/M .2
-`c:}m
System.err.println("文件下载结束！"); xycH~ ?
} |BU+:+
catch(Exception e){e.printStackTrace ();} y6HuN
} D$eB ,~
J]/}ojW3
u62)QJE
//获得文件长度 @Cq? :o<
public long getFileSize() bMoAD.}
{ 5"Kx9n|
int nFileLength = -1; _Tm0x>EM
try{ [\ )Ge
URL url = new URL(siteInfoBean.getSSiteURL()); @]CF&: P A
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); I=DLPgzO9
httpConnection.setRequestProperty("User-Agent","NetFox"); dx_6X!=.J
l0]d
{OMgd3%14
int responseCode=httpConnection.getResponseCode(); ),^eA
if(responseCode>=400) w2gf&Lc\
{ W=}Okq)x9I
processErrorCode(responseCode); XFZ~ #DT&
return -2; //-2 represent access is error B33$ u3d
} <|6%9@
y7u^zH6wj
WV<tyx9Z
String sHeader; _uxPx21g}
+RZ~LA\+
6)RbPPeE
for(int i=1;;i++) P<dy3;
{ i\}:hU-U
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); J@"utY6N
//Utility.log(in.readLine()); IfdI|ya
sHeader=httpConnection.getHeaderFieldKey(i); 2i=H"('G)+
if(sHeader!=null) dXvt6kF
{ ~XM[>M\qB
if(sHeader.equals("Content-Length")) JyBp-ii
{ FY0%XW
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); %FkLQ+v/<
break; $ACx*e%
} RNJFSD.
} ,32xcj}j)r
else ks(SjEF
break; a=}*mF[ug
} Wsz0yHD[`
} *dE^-dm#
catch(IOException e){e.printStackTrace ();} D>ef
catch(Exception e){e.printStackTrace ();} -$8.3\6h
D9ufoa&ua
mX# "+X|
Utility.log(nFileLength); LgqGVh3\s
$n=lsDnhQ
HD`>-E#
return nFileLength; 3Kq`<B~%
} M].8HwC+
w<wV]F*
,{}#8r`+*
//保存下载信息（文件指针位置） =yiOJyx
private void write_nPos() >>'C :7+Y
{ Q\_{d0 0
try{ 59 2;W-y
output = new DataOutputStream(new FileOutputStream(tmpFile)); x"B'zP
output.writeInt(nStartPos.length); v|t{1[C
for(int i=0;i<nStartPos.length;i++) ISqfU]>[
{ 'ig, ATY
// output.writeLong(nPos); |7F*MP
output.writeLong(fileSplitterFetch.nStartPos); 649 !=
output.writeLong(fileSplitterFetch.nEndPos); [Eq<":)
} a+z2Zd!u\x
output.close(); /p`&;/V|
} ? Nj)6_&
catch(IOException e){e.printStackTrace ();} zmFws-+A
catch(Exception e){e.printStackTrace ();} mV\$q@sII
} n'w,n1z7
&y.dmW
)C]x?R([m
//读取保存的下载信息（文件指针位置） ?[1SiJT
private void read_nPos() .Ao0;:;(2-
{ )iE"Tl
try{ D'i6",Z>
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); !C&%T]
int nCount = input.readInt(); 'CV^M(o'9
nStartPos = new long[nCount]; 7>.OVh<
nEndPos = new long[nCount]; J\`^:tcG
for(int i=0;i<nStartPos.length;i++) I0w%8bs
{ KCqqJ}G
nStartPos = input.readLong(); &d^=siL
nEndPos = input.readLong(); S7sb7c'4 k
} ^X?D#\
input.close(); szq+@2:
} YMzBAf
catch(IOException e){e.printStackTrace ();} (F5ttQPh
catch(Exception e){e.printStackTrace ();} o}D![/
} otriif@+Z
Da,Tav%b
VWa|Y@Dc]
private void processErrorCode(int nErrorCode) B@cz ?%]
{ \+B?}P8N*l
System.err.println("Error Code : " + nErrorCode); WmVVR>0V|
} l)Mh2lA,=
&?<AwtNN
I'_v{k5ZI
//停止文件下载 lo:~aJ8
public void siteStop() f%Ke8'&
{ d6b.zP
bStop = true; /~hbOs/ L
for(int i=0;i<nStartPos.length;i++) lX;mhJj!
fileSplitterFetch.splitterStop(); g [L
e-6(F4
myvh@@N
} kK?zVH-!
} " i`8l.Lc
//负责部分文件的抓取 6VR[)T%
**FileSplitterFetch.java 'lQYJ0
*/ L8P36]>
package NetFox; l9Pu&M?5
K-@bwB7~s
Bl4 dhBZoO
import java.io.*; jgRCs.6
import java.net.*; 9ECS,r*B
chLeq
#s^s_8#&e
public class FileSplitterFetch extends Thread { .<w)Bmh
:~-i&KNk
<!!nI%NC
String sURL; //File URL AU`OESSI
long nStartPos; //File Snippet Start Position NbDda/7ki
long nEndPos; //File Snippet End Position B9W/bJ6%
int nThreadID; //Thread's ID jtLnj@,
boolean bDownOver = false; //Downing is over .0 X$rX=
boolean bStop = false; //Stop identical $rB!Ex{@ac
FileAccessI fileAccessI = null; //File Access interface FO^24p
8MQbLj'H
?N_)>&b
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException 1ypjyu
{ ,\>g
this.sURL = sURL; m3"c (L`B
this.nStartPos = nStart; I~k=3,7<
this.nEndPos = nEnd; sL mW\\kA>
nThreadID = id; sD2Qm
fileAccessI = new FileAccessI(sName,nStartPos);//定位 T#N80BH[
} 6vWii)O.D
l#ygb|=x
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public void run() +{^'i P
{ FvA|1c
while(nStartPos < nEndPos && !bStop) =W|vOfy
{ Bxt_a.LthH
Gl"wEL*
w= B
try{ v?{vg?vI
URL url = new URL(sURL); vVdxi9yk
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); !xH,y
httpConnection.setRequestProperty("User-Agent","NetFox"); 8E=vR 8
String sProperty = "bytes="+nStartPos+"-"; ~=Fk/
httpConnection.setRequestProperty("RANGE",sProperty); o[imNy~~
Utility.log(sProperty); *V<)p%l.
#4lHaFq
Sy:K:Z|[U
InputStream input = httpConnection.getInputStream(); \`&xprqAw
//logResponseHead(httpConnection); qs "s/$
"V:XhBG?
@21u I{
byte[] b = new byte[1024]; n }TTq6B
int nRead; KG-UW
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) yq!CWXZ2
{ x6jm-n
nStartPos += fileAccessI.write(b,0,nRead); O/nqNQ?<
//if(nThreadID == 1) WEps.]s
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 7Z VVR*n|
} ^`/V i
z3ZuC{
65uZLsQ
Utility.log("Thread " + nThreadID + " is over!"); >*Sv0#
bDownOver = true; ?3n=m%W,J*
//nPos = fileAccessI.write (b,0,nRead); j#CuR7m
} 0NVG"-Q
catch(Exception e){e.printStackTrace ();} &8zk3
} ~xP Szf
} 2k%Bl+I
fO0-N>W'P
Q4#\{" N!
//打印回应的头信息 Cx$9#3\
public void logResponseHead(HttpURLConnection con) zkH<aLRB
{ <.: 5Vx(Aw
for(int i=1;;i++) T3 =)F%
{ gq=0L:
String header=con.getHeaderFieldKey(i); 69N1 mP
if(header!=null) {E3;r7
//responseHeaders.put(header,httpConnection.getHeaderField(header)); 4 3}qaf[
Utility.log(header+" : "+con.getHeaderField(header)); TeOFAIU
else #@IQlqJfY7
break; M_yZR^;^-
} o@Dk%LxP
} VOD1xWrb
#d3[uF]OmW
L!`*R)I45
public void splitterStop() :Xb*m85y
{ % E<FB;h
bStop = true; =#7s+d-
} ;]|m((15G
T@2f&Un^
Ufyxw5u5F
} S^*(ALFPj
}Ox2olUX
avF&F
/* *9\oD~2Y
**FileAccess.java e,PQ)1
*//文件访问(定位，写) NHst7$Y<
package NetFox; =f/avGX
import java.io.*; wI|bBfd(
6,sRavs
7N&3FER
public class FileAccessI implements Serializable{ ,:\zXESy4
ZYpD8u6U
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 ]IN-
RandomAccessFile oSavedFile; aTmX!!
long nPos; BN bb&]
DR#3njjEC
;tZ}i4Ud
public FileAccessI() throws IOException lk5_s@V l
{ &@Ji+
this("",0); J~PTVR
} /jn:e"0~
Br?++\
&k {t0>
public FileAccessI(String sName,long nPos) throws IOException ?Vb=4B{~
{ 5cv, >{~5
oSavedFile = new RandomAccessFile(sName,"rw"); t/4/G']W
this.nPos = nPos; zXA= se0U
oSavedFile.seek(nPos); lUm}nsp=X
} 0:nt#n~_
U/~Zk@3j
^$^Vd@t>a
public synchronized int write(byte[] b,int nStart,int nLen) #oS
{ >Kqj{/SWK
int n = -1; eFeCS{LV+
try{ l%3Q=c
oSavedFile.write(b,nStart,nLen); 60SenHKles
n = nLen; w^vK7Z 1$
} MzA
catch(IOException e) xfZ9&g
{ rSzXa4m(
e.printStackTrace (); Q}`2Y^.
} h_}BmJh_
lqwJ F &
ce-m)o/
return n; %QlBFl0a
} +=lcN~U2
omDi<-
#6#BSZ E
} =&<$I
&dHm!b
pu m9x)y1
/* RI<Yg#
**SiteInfoBean.java 5<>R dLo
*/ Xj&~N;Ysb
package NetFox; D=Yag!1
LxYM"_1A;
e&VR>VJEA
public class SiteInfoBean { T[2f6[#[_
WG!;,~f>o
~dX@5+Gd
private String sSiteURL; //Site's URL Z!BQtICs
private String sFilePath; //Saved File's Path sfBjA
private String sFileName; //Saved File's Name /A`zy
private int nSplitter; //Count of Splited Downloading File =<27qj
Eo3Aak o
z jNjmC!W
public SiteInfoBean() Hi 0df3t
{//nSplitter的缺省值为5 ]9l%
//default value of nSplitter is 5 $9u
this("","","",5); "vHAp55B{
} %BP)m(S7
e"8m+]
"oGM>@q=B
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) pkMON}"mj
{ x;b+gIz*
sSiteURL= sURL; lPSDY&`P
sFilePath = sPath; }R] }@i~i
sFileName = sName; $oBZe>s.
this.nSplitter = nSpiltter; "a_D]D(d5
XQoT},C
7Mbt*[n
} ""KN?qh9
)|1JcnNSa
!/lYq;$R
public String getSSiteURL() oL/^[TXjH
{ H\>I&gC'
return sSiteURL; A2FU}Ym0=
} #YMp,i
^T1-dw(
blkJm9]v
public void setSSiteURL(String value) ~0$F V
{ >WS&w;G
sSiteURL = value; NqfDY
} g.sV$.T2K
=id $
:[rKSA]@
public String getSFilePath() $Lbe5d?\
{ 0\<-R
return sFilePath; aC6b})^
} JBJ7k19;
~O7(0RsCN
9<r}s
public void setSFilePath(String value) -"tgEC\tD
{ -ZON']|<}k
sFilePath = value; YD.^\E4o
} 1^>g>bn_"
%hb5C 4q
"4AQpD
public String getSFileName() "8 mulE,
{ QYb?;Z
return sFileName; Bj[/tQ
} |6Z MxY
=8D4:Ds
F|K4zhK
public void setSFileName(String value) +E[)@;T
{ :P1c>:j[
sFileName = value; bbkI}d%(Ng
} Ax*~[$$~%
z$5C(!)
.O.R
public int getNSplitter() E\N=p&g$
{ vp9<.*h
return nSplitter; ?0%TE\I8
} LkB!:+v |B
/~5YTe(F
.u?$h0u5
public void setNSplitter(int nCount) x7@HPf
{ ,LO-!\L
nSplitter = nCount; mcG$V0D <{
} cN>i3}fq
} W-QPO
5/ju it
,RO(k4
/* >MrU^t
**Utility.java IW_D$pq
*/ (W!$6+GT
package NetFox; VrxH6Y
Acv{XnB
R |%
public class Utility { Z?mg1;Q
A$6b=2hc>
Af<>O$$6
public Utility() n82Q.M-H
{ V~Lq,oth
D|:sSld @
f|0QN#$
} LS;anNk@.}
]l%.X7M9
//线程睡眠 Ti'kn{ Zv
public static void sleep(int nSecond) vDvGT<d
{ <DS6-y
try{ 3>Snd9Q
Thread.sleep(nSecond); n<*]`do,w
} N@)~j+Pz
catch(Exception e) 3fTI&2:
{ 3kY4V*9@-
e.printStackTrace (); NkI:
} ]'/]j
} hM w`e
Am4(WXVQ
//日志 p\S3A(
public static void log(String sMsg) x~eEaD5m%J
{ W<o0Z OO
System.err.println(sMsg); eS:e#>(
} DA~ELje^j
|vzWSm
nUHVPuQ/'T
public static void log(int sMsg) & jvG]>CS'
{ EQC
System.err.println(sMsg); GYxI$y0:
} ze N!*VG
} Iq\oB
uD5yw#`
G9Tix\SpF
/* 12dW:#[
**TestMethod.java x$DJ
*/ faX#KRpfd
package NetFox; 2"mj=}y6
7+4"+CA
o#/iR]3
public class TestMethod { 1H7Q[ 2E
^#se4qQ
mC(t;{
public TestMethod() DjvgKy=Jr_
{ ///xx/weblogic60b2_win.exe 38i,\@p`9$
try{ k]pD3.QJ
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); v"~I( kf$
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); u_=y,~s
SiteFileFetch fileFetch = new SiteFileFetch(bean); s;$TX304
fileFetch.start(); pUGfm
} Z]\^.x9S
catch(Exception e){e.printStackTrace ();} =A6O}0z
d<nB=r!*
/j@ `aG(a
} {`CWzk?
~')t1Ays
>Fk`h=Wd
public static void main(String[] args) |9Ks13?Ck
{ Qp&ySU8
new TestMethod(); Uy|=A7Ad c
} wJ*-K-
} w{x(YVSH
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