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)); :iK(JE`
} yd^{tQi
for(int i=0;i<nEndPos.length-1;i++) F<ZYh
{ \<&m&%Zs
nEndPos = nStartPos[i+1]; 0Be<X
} :I"2V
nEndPos[nEndPos.length-1] = nFileLength; xj<Rp|7&
} _- [''(E
} aB*Bz]5;E
+s"hqm
_A M*@|p,
//启动子线程 9 3U_tQ&1?
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; a_[Eh fE
for(int i=0;i<nStartPos.length;i++) 5 z~1Dw
{ N@;?CKU
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), !!qK=V|>
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), 3RiWZN
nStartPos,nEndPos,i); TIx|L
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); a:+{f&
fileSplitterFetch.start(); \@-@Y
} :Gv1?M
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), (ScxLf=]
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); ~{?_p@&n
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", JHW"-b
nEndPos = " + nFileLength); 3ovWwZ8&
// fileSplitterFetch[nPos.length-1].start(); ylUrLQ\
<z+t,<3D
yTyj'-4
//等待子线程结束 rJd,Rdt.
//int count = 0; zuP B6W^
//是否结束while循环 +QB"8-
boolean breakWhile = false; Bm.afsM;
?J'Y&
pEw"8U
while(!bStop) ke{8 ^X~#
{ uzXCIv@
write_nPos(); I\hh8abAp
Utility.sleep(500); +U:$(UV'A
breakWhile = true; hrmut*<|
6.FY0.i
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for(int i=0;i<nStartPos.length;i++) )Z[ft
{ J`^ag'
if(!fileSplitterFetch.bDownOver) xE1 eT,
{ k[0-CB
breakWhile = false; <CRP^_c
break; P<oehw'>
} PxF<\pu&
} :#2Bw]z&z
if(breakWhile) M]<?k]_p
break; UsgK
rMXN[,|v
ADZ};:]
//count++; 0,r}o
//if(count>4) ( Wa
// siteStop(); 8m5p_\&
} ot@|!V
hZ[E7=NTQ^
4f@o mAM
System.err.println("文件下载结束！"); 'AzDP;6qFI
} mt9.x
catch(Exception e){e.printStackTrace ();} Vw[6t>`
} v. %R}Pa
tc_286'x
jATI&oX
//获得文件长度 a-y+@#;2_
public long getFileSize() %R1tJ(/
{ ()tp>
int nFileLength = -1; ilK-?@u+
try{ 3Uqr,0$p
URL url = new URL(siteInfoBean.getSSiteURL()); rJFc({ 0
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 0ph{
httpConnection.setRequestProperty("User-Agent","NetFox"); ]'5;|xc9$/
|4 v0:ETb$
-yR.<KnL
int responseCode=httpConnection.getResponseCode(); qL5{f(U4<
if(responseCode>=400) b'P eH\h{
{ K6y :mJYp\
processErrorCode(responseCode); ZPc@Zr`z
return -2; //-2 represent access is error ?aC'.jH+
} MWI4Y@1bS
RZ6xdq}>
|"XPp!_uN
String sHeader; .udv"?!z
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zR `EU,
for(int i=1;;i++) _tSAI
{ ,REJt
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); xO1[>W
//Utility.log(in.readLine()); !icT/5
sHeader=httpConnection.getHeaderFieldKey(i); e2z h&j
if(sHeader!=null) uMut=ja(U
{ XGJj3-eW{
if(sHeader.equals("Content-Length")) .w> 4
{ ]BtbWKJBqe
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); OS4q5;1#
break; \ W?R
} /c"efnb!
} $BkubWM
else _2k]3z?
break; d}LRl"_n
} I#m-g-J
} xfy1pS.[:
catch(IOException e){e.printStackTrace ();} b8$gx:aJ>$
catch(Exception e){e.printStackTrace ();} fBgEnz/
NM]s8cK_
%YSpCI
Utility.log(nFileLength); F6o_b4l
NB\{'
'\Jj8oJQj
return nFileLength; *.~6S3}
} "]oO{'1X
"Vw m
=8r 0 (c
//保存下载信息（文件指针位置） !O.[PH(,*
private void write_nPos() {o!KhF:[
{ Zq,9&y~
try{ '"?C4mbSl
output = new DataOutputStream(new FileOutputStream(tmpFile)); >$ NDv
output.writeInt(nStartPos.length); aFe`_cnG
for(int i=0;i<nStartPos.length;i++) "Fy7K#n
{ L KCb_9
// output.writeLong(nPos); vj51 g@
output.writeLong(fileSplitterFetch.nStartPos); 6ZKsz5:=
output.writeLong(fileSplitterFetch.nEndPos); ?lbH02P{v
} L7= Q<D<
output.close(); ,g7.rEA
} VA"*6F
catch(IOException e){e.printStackTrace ();} !ALKSiSl
catch(Exception e){e.printStackTrace ();} i `s|,"0o
} s:2|c]wQ#R
HQUeWCN
Mmo6MZ^
//读取保存的下载信息（文件指针位置） ,h{A^[yl
private void read_nPos() aWwPvd3
{ U3izvM
try{ >_c5r?]SG
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); G [:N0{v5
int nCount = input.readInt(); dWXstb:[
nStartPos = new long[nCount]; bn(`O1r[(
nEndPos = new long[nCount]; QJ F=UB
for(int i=0;i<nStartPos.length;i++) {ekCQeDo
{ BnCKSg7V
nStartPos = input.readLong(); UWZa|I~:J
nEndPos = input.readLong(); mCs#.%dU
} j ,)P9V
input.close(); :-iMdtm
} nLwiCfe
catch(IOException e){e.printStackTrace ();} =\,uy8HX
catch(Exception e){e.printStackTrace ();} 5jgdbHog]
} rrnNn'
zOHypazOTq
Nrah;i+H\o
private void processErrorCode(int nErrorCode) |+:h|UIUQ
{ t ?h kL
System.err.println("Error Code : " + nErrorCode); ]&ixhW
} &(zfa&j|
mv atUe
'JZJFE7Z
//停止文件下载 ewuXpv%vwW
public void siteStop() 'q>2t}KG
{ &3v&i*DG,I
bStop = true; `e]6#iJ^
for(int i=0;i<nStartPos.length;i++) -ZW3
fileSplitterFetch.splitterStop(); <]Wlx`=/D
0Rz(|jlbS
oyk>vIZ
} R0;efD
} B51kV0
//负责部分文件的抓取 `_5GG3@Ff
**FileSplitterFetch.java J9%@VZut
*/ Fl{WAg
package NetFox; 3ta$L"a
o5Y2vmz?9
joa5|t!D9
import java.io.*; S'U@X
import java.net.*; ]h!`IX
#hL*rbpT
mxFn7.|r~
public class FileSplitterFetch extends Thread { 7m9"8
u>.y:>
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String sURL; //File URL ~2uh'e3
long nStartPos; //File Snippet Start Position Y7U&Q:5'
long nEndPos; //File Snippet End Position Qu%D
int nThreadID; //Thread's ID !q4x~G0d
boolean bDownOver = false; //Downing is over RbQ <m!A
boolean bStop = false; //Stop identical 4B-yTyO
FileAccessI fileAccessI = null; //File Access interface b X)|MiWI
:a3LS|W
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public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException qJ8-9^E,L
{ {<w +3Va
this.sURL = sURL; ^m7~:=K7WG
this.nStartPos = nStart; *]s&8/Gmb
this.nEndPos = nEnd; Xt,X_o2m|]
nThreadID = id; TYjA:d9YH
fileAccessI = new FileAccessI(sName,nStartPos);//定位 en9en=n|
} zW4O4b$T
ua 8m;>R
}fIqH4bp
public void run() j%& IL0
{ Ff"gadRXd
while(nStartPos < nEndPos && !bStop) kI*UkM-
{ tLX,+P2|
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5n:71$6[
try{ [{F%LRCo-
URL url = new URL(sURL); f\ "`7
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); sms1%%~
httpConnection.setRequestProperty("User-Agent","NetFox"); pbB2wt
String sProperty = "bytes="+nStartPos+"-"; T$b\Q
httpConnection.setRequestProperty("RANGE",sProperty); BpT"~4oV5
Utility.log(sProperty); UR>_)*
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o+)A'S
InputStream input = httpConnection.getInputStream(); ^o%_W0_r
//logResponseHead(httpConnection); =Nl5{qYz^&
z Bf;fi
kfpm=dKL
byte[] b = new byte[1024]; N+>'J23d!
int nRead; sX'U|)/pD
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) p~>_T7ze
{ Hptq,~_t
nStartPos += fileAccessI.write(b,0,nRead); sC6r.@[u8t
//if(nThreadID == 1) Pe,;MP\2
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); |[wyc!nY).
} a"qR J-@
u&3EPu
m'.T2e.u
Utility.log("Thread " + nThreadID + " is over!"); fu>Qi)@6a1
bDownOver = true; FrR9{YTA.
//nPos = fileAccessI.write (b,0,nRead); U2&HSE|2J
} e 2*F;.)
catch(Exception e){e.printStackTrace ();} -M`D>
} Gmgeve
} b3^R,6]x&
x[}06k'
z\h,SX<U
//打印回应的头信息 z[FI2jl
public void logResponseHead(HttpURLConnection con) ;zm ks]
{ tBTJmih"
for(int i=1;;i++) NV(fN-L
{ 49y*xMn
String header=con.getHeaderFieldKey(i); ?7rD42\8H
if(header!=null) 6 <r2*`
//responseHeaders.put(header,httpConnection.getHeaderField(header)); iiehrK&T!
Utility.log(header+" : "+con.getHeaderField(header)); _}z_yu#jY
else wjg}[R@!
break; g(aNyn
} L+(C5L93}
} Z3I L8
B^Bbso'{1
8q{1E];:q
public void splitterStop() yj]ML:n
{ dd19z%
bStop = true; wC(XRqlE
} ^VC7C~NZ!M
6BR\iZ
"?`JA7~g
} 5@CpP-W#
+0dQORo
kkHTbn=!
/* 3[iSF5%V*p
**FileAccess.java )fy<P;g
*//文件访问(定位，写) dqL-'
package NetFox; 3[,wMy"
import java.io.*; e%'z=%(
%h3L
@-}D7?
public class FileAccessI implements Serializable{ %f>X-*}NI-
v hR twi
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 Ny]'RS-
RandomAccessFile oSavedFile; <8g *O2
long nPos; XX*'N+
DBLA% {05
p6B .s_G4
public FileAccessI() throws IOException :,urb*
{ :Pj W:]
this("",0); r.Y*{!t
} h85(N
l7!U),x%/U
>cBGw'S
public FileAccessI(String sName,long nPos) throws IOException 7=$+k]U8
{ J(3gT}z-
oSavedFile = new RandomAccessFile(sName,"rw"); `wP/Zp{Hy
this.nPos = nPos; 8=lHUn9l
oSavedFile.seek(nPos); N8Rm})
} bbfDt^
bbE bf !E
?Ry%c6(}
public synchronized int write(byte[] b,int nStart,int nLen) iSSc5ek4
{ ?|%\<h@;
int n = -1; ckH$E%j
try{ K> c8r8!
oSavedFile.write(b,nStart,nLen); x`};{oz;
n = nLen; q[PD
} OqEg{o5 a&
catch(IOException e) owfp^hla
{ $[HcHnf
e.printStackTrace (); "N?%mCPI
} B[) [fE
6Tm Rc
`<l/GwtAJ
return n; n"^/UQ|#j
} lpM>}0v
]Ssw32yn
Q:-%3)g<<
} y(aAp.S>
@2GhN&=
s2(w#n)
/* O<eWq]
**SiteInfoBean.java Mp^OL7p^^
*/ l0:e=q2Ax
package NetFox; AHp830\
.-O@UQx.I
p]1yd;Jt
public class SiteInfoBean { d'Ik@D]I
T!^?d5uW#
t?du+:
private String sSiteURL; //Site's URL 8xD<A|
private String sFilePath; //Saved File's Path .b_0k<M!p
private String sFileName; //Saved File's Name =ELDJt
private int nSplitter; //Count of Splited Downloading File )JY_eG&2Dx
oPBg+Bh*
lgv-)5|O+H
public SiteInfoBean() ,E/Y@sajn+
{//nSplitter的缺省值为5 |5<&r]xN
//default value of nSplitter is 5 P*0nT
this("","","",5); NSxPN:
} </+%R"`
w$(0V$l_
H/p-YtY
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) &k_wqV
{ @qO8Jg"Q
sSiteURL= sURL; #^4>U&?
sFilePath = sPath; Zy!)8<Cgm'
sFileName = sName; 5E\<r/FeJ
this.nSplitter = nSpiltter; R+kZLOE
['}^;Y?*o
@ (u?=x;
} O yH!V&w
z|DA _dG
Y|0-m#1F#
public String getSSiteURL() O{i_?V_
{ >Xh(`^}SQ*
return sSiteURL; avxn}*:X.
} zI2KIXcc
CyK$XDHa
@aiLGwh
public void setSSiteURL(String value) }x#P<d(
{ !OZhfMVd
sSiteURL = value; &x0TnW"g
} +U_-Lq )
<zDw&s2
{Y*]Qc
public String getSFilePath() ^;k _
{ Lx:N!RDw
return sFilePath; U38wGSG
} _E&vE5<-$
"!6 B5Oz
oRbYna?J
public void setSFilePath(String value) iQ]c k-
{ /o1)ZC$
sFilePath = value; 0h@%q;g
} s[B6%DI/5
SJ[@fUxO)
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public String getSFileName() |phWK^
{ +|"n4iZ!)
return sFileName; :D+SY
} CMG`'gT
ma-Y'
UWWD8~:
public void setSFileName(String value) ;gW|qb+#)j
{ K7O?{/
sFileName = value; ?-F'0-t4%
} ]qza*ba
rDx],O _
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public int getNSplitter() &?g!}Ky \
{ !zkEh9G
return nSplitter; ^57fHlw
} OO wA{]gK
T17LYHIT
OI}HvgV^!
public void setNSplitter(int nCount) !g&B)0u]*
{ So 6cm|{
nSplitter = nCount; UlN|Oy,
} VUv.Tx]Z[
} ZznWs+
Ng39D#_)
+}0*_VW
/* ,h`D(,?X
**Utility.java BBJ]>lQ
*/ m.a1
package NetFox; 2b,TkG8K
RF2XJJ
kpw4Mq@
public class Utility { hPpXB:(-0
d1La7|43u
E=*Q\3G~
public Utility() <~X6D?
{ 1sLfjH hv
?N*@o.
=<h=">}5'
} "K!BJQ
|M>k &p,B-
//线程睡眠 a&VJYAB
public static void sleep(int nSecond) *dTf(J
{ Z_~DTO2Qg
try{ jeFl+K'1
Thread.sleep(nSecond); DmPsltpzQ
} 3D dG$@
catch(Exception e) k$_]b0D{4
{ L5uI31
e.printStackTrace (); 3'e 4{
} I_*>EA
} ,VsCRp
, tj7'c$0
//日志 OBSJbDqT
public static void log(String sMsg) DkKD~
{ qM !q,Q
System.err.println(sMsg); F|Ihq^q
} Q^w]Nj(e_
oXkhj,{y5
X}Z%@tL
public static void log(int sMsg) IfCqezd
{ 6&0a?Xu
System.err.println(sMsg); .WE0T|qDX
} s7} )4.vO
} DP]|}8~L
e'VXyf
OR8o%AxL7
/* /n:fxdhe
**TestMethod.java AR3=G>hO,
*/ xyz86r ^u
package NetFox; O_Q,!&*6
k8V0-.UL}
IpmREl$j
public class TestMethod { 9ksrr{tW
=oDrN7`,B
0pOha(,~
public TestMethod() )^sfEYoA
{ ///xx/weblogic60b2_win.exe O8o18m8UH
try{ P[i/o#
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); e)"cm;BJ^P
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); v4aGL<SO
SiteFileFetch fileFetch = new SiteFileFetch(bean); a$8?0`(
fileFetch.start(); {rLOAewr
} B=|sLs`I
catch(Exception e){e.printStackTrace ();} IPR396J+-
Yg.u8{H
R FiR)G ,
} <~w#sIh
PX)qA=4q
h%S#+t(Bf
public static void main(String[] args) (p!AX<=z
{ +Wc[$,vk
new TestMethod(); iwJgU b
} -NeF6
} FG\?_G
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