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)); ~3h-jK?
} pY8q=Kl
for(int i=0;i<nEndPos.length-1;i++) JWP*>\P
{ V:NI4dv/R
nEndPos = nStartPos[i+1]; XJ0{
} FE7)E.U
nEndPos[nEndPos.length-1] = nFileLength; nQK|n^AU/
} hv$yV%.`
} E .6HpIx
4A`NJ
"I- w
//启动子线程 #!J(4tXny
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ^cvl:HOog
for(int i=0;i<nStartPos.length;i++) 'fwU]Hm
{ &sVvWNO#2
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), {Z;t ^:s#
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), @gGRm
nStartPos,nEndPos,i); 6~meM@
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); DrW#v-d
fileSplitterFetch.start(); [|`U6 8}u
} -_VG;$,jE
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), M.}7pJ7f
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); #b0{#^S:
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", _1Z=q.sC
nEndPos = " + nFileLength); lt'I,Xt
// fileSplitterFetch[nPos.length-1].start(); Eu<1Bse;
>"3>s%
#Sg\q8(O
//等待子线程结束 L?&'xzt B
//int count = 0; s$h] G[x
//是否结束while循环 !7B\Xl'S
boolean breakWhile = false; )o _j]K+xI
+0z 7KO%^^
_cDF{E+;
while(!bStop) _+f+`]iM
{ }}{!u0N},V
write_nPos(); 6"j_iB
Utility.sleep(500); {.e=qQ%P5)
breakWhile = true; "R #k~R
woH)0v
w[Gh+L30=5
for(int i=0;i<nStartPos.length;i++) 72oWhX=M%
{ 1m<RwI3s
if(!fileSplitterFetch.bDownOver) qUF'{K
{ eKZ%2|+j!7
breakWhile = false; v*hRz;
break; .]4W!])9
} RWq{Ff}Hk
} /G{_7cb
if(breakWhile) Wa/g`}
break; 3M*Bwt;F_
P3tx|:gV
G1T^a>tj4
//count++; Q'apG)0I
//if(count>4) 8 }'|]JK
// siteStop(); 3. WF}8
} =H7xD"'%R
`rY2up#%
jLg@FDb~
System.err.println("文件下载结束！"); -#`c5y}P
} ;a"q'5+Ne
catch(Exception e){e.printStackTrace ();} Nw J:!
} aiCFH_H4;L
]bCq=6ZKR
] 7;f?+
//获得文件长度 l":c
public long getFileSize() )bOBQbj
{ 5R MS(
int nFileLength = -1; cRvvzX
try{ 2R-A@UE2
URL url = new URL(siteInfoBean.getSSiteURL()); Tq<2`*Qs
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); [}mA`5
httpConnection.setRequestProperty("User-Agent","NetFox"); @* 1U{`
TrVWv
=#5D(0Ab
int responseCode=httpConnection.getResponseCode(); <T?oKOD ]
if(responseCode>=400) OqhD7 +
{ @pV5}N[]
processErrorCode(responseCode); z(RL<N%
return -2; //-2 represent access is error ~K_Uq*dCE
} 7;`o( [N
D8K-K]W@
;_kzcK!l
String sHeader; &UHPX?x
_=6 rE
z|R,&~:
for(int i=1;;i++) w [>;a.$
{ "pxzntY|
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); &YP#M|
//Utility.log(in.readLine()); #eP LOR&q
sHeader=httpConnection.getHeaderFieldKey(i); 2B~wHv
if(sHeader!=null) Kz8:UG(
{ "kMzmo=Pv5
if(sHeader.equals("Content-Length")) =64r:E
{ Eq%@"-mo
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); D,l,`jv*
break; $L4/I!Yf
} 5vzceQE}
} wHjLd$ +o
else FwKj+f"
break; =Yo1v=wxN
} eS/B24;*
} {X]R-1>
catch(IOException e){e.printStackTrace ();} 9Vuq,dv
catch(Exception e){e.printStackTrace ();} _gNz9$S
2U kK0ls
,"-Rf<q/
Utility.log(nFileLength); G%p~m%zIK
&>WWzikB*
2Tav;LKX
return nFileLength; pVp:@0h
} 5`/@N{e
.@ C{3$,VG
Rn%N&1 Ef
//保存下载信息（文件指针位置） Ko>&)%))$X
private void write_nPos() cNpe_LvW
{ 4o:hyh
try{ wbyE;W
output = new DataOutputStream(new FileOutputStream(tmpFile)); '&O/g<Z}q
output.writeInt(nStartPos.length); ^(}585b
for(int i=0;i<nStartPos.length;i++) NMO-u3<6.
{ w JwX[\
// output.writeLong(nPos); $Kj&)&M
output.writeLong(fileSplitterFetch.nStartPos); %b.UPS@I
output.writeLong(fileSplitterFetch.nEndPos); fBtm%f
} 8{U-m0v
output.close(); ~%u|[$
} $S*4r&8ZD
catch(IOException e){e.printStackTrace ();} hlZ@Dq%f
catch(Exception e){e.printStackTrace ();} UAF<m1
} $$Vt7"F
rtJl _0`
tqPx$s
//读取保存的下载信息（文件指针位置） q}uHFp/J
private void read_nPos() W_O)~u8
{ +Z2MIC|Ud
try{ 3 vP(SIF
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); 5M]z5}n/
int nCount = input.readInt(); {MAQ/5
nStartPos = new long[nCount]; ;32#t[ib
nEndPos = new long[nCount]; y@bcYOh3
for(int i=0;i<nStartPos.length;i++) pb60R|k
{ (<t_Pru
nStartPos = input.readLong(); /e\{
nEndPos = input.readLong(); z!QDTIb
} `+lHeLz':
input.close(); =bh*[,-
} ~H)4)r^
catch(IOException e){e.printStackTrace ();} "i.r@<)S
catch(Exception e){e.printStackTrace ();} nm$Dd~mxW1
} Thy=yz;p
SQsSa1
bok.j
private void processErrorCode(int nErrorCode) <BWkUZz\P|
{ pZZgIw}aS
System.err.println("Error Code : " + nErrorCode); LgmvKW|
} &MR/6"/s
z9 u$~
D;GD<zC]
//停止文件下载 qVjWV$j
public void siteStop() 5lKJll^2:
{ FFhtj(hVgc
bStop = true; 1 "TVRb
for(int i=0;i<nStartPos.length;i++) =6FUNvP#8
fileSplitterFetch.splitterStop(); gV1[3dW
?71+f{s
&Wp8u#4L
} S,fCV~Cio?
} z@s5m}
//负责部分文件的抓取 O40+M)e]
**FileSplitterFetch.java 1:C:?ZC#c
*/ n6WY&1ZE~
package NetFox; 3OyS8`
+`mGK:>
ymY1o$qWB}
import java.io.*; =+5,B\~q@C
import java.net.*; ,?UM;^
Eu}b8c
5/",<1
public class FileSplitterFetch extends Thread { 6[qA`x#
pN6%&@) =
x"kjs.d7[<
String sURL; //File URL }*]B-\>
long nStartPos; //File Snippet Start Position v1U?&C
long nEndPos; //File Snippet End Position )/ Ud^wi
int nThreadID; //Thread's ID Rx07trfN
boolean bDownOver = false; //Downing is over =*BIB5
boolean bStop = false; //Stop identical e;bYaM4UX
FileAccessI fileAccessI = null; //File Access interface Mpue
8rZ!ia!
CF!Sa6
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException MmPU7Nl%X
{ seFGJfN\?f
this.sURL = sURL; =-cwXo{Q.O
this.nStartPos = nStart; l@j.hTO<
this.nEndPos = nEnd; vgIpj3u
nThreadID = id; A*h{Lsx;
fileAccessI = new FileAccessI(sName,nStartPos);//定位 i LBvGZ<9
} +.B<Hd
U=Y)V%
1[F3 Z
public void run() HysS_/t~
{ Z#d&|5Xj
while(nStartPos < nEndPos && !bStop) ?rVy2!
{ F~#zxwd
6dH }]~a
h!@|RW&}qX
try{ #qU-j/Qf
URL url = new URL(sURL); gbOpj3
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); DF]9@{
httpConnection.setRequestProperty("User-Agent","NetFox"); E"iUq
String sProperty = "bytes="+nStartPos+"-"; &adI (s~
httpConnection.setRequestProperty("RANGE",sProperty); d9*hBm
Utility.log(sProperty); uf<@ruN
KT|RF
mpC`Yk
InputStream input = httpConnection.getInputStream(); }uHrto3M
//logResponseHead(httpConnection); iF5'ygR-Z
GY3Wj
;rI@*An
byte[] b = new byte[1024]; 5V[oE\B
int nRead; 5la>a}+!!h
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) .JX EK
{ +=Jir1SLV
nStartPos += fileAccessI.write(b,0,nRead); ,&PE6hn
//if(nThreadID == 1) VLsxdwHgb
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); C,V%B
} 7`vEe'qz
O-]mebTvw
G2 ]H6G$M
Utility.log("Thread " + nThreadID + " is over!"); !J1rRPV
bDownOver = true; _cTh#t ^
//nPos = fileAccessI.write (b,0,nRead); 'oNO-)p\#!
} DBLk!~IF
catch(Exception e){e.printStackTrace ();} *,C(\!b !?
} _$NIp `d
} q>f<u&
(z7vl~D
rt3qdk5U
//打印回应的头信息 # ?1Sm/5k`
public void logResponseHead(HttpURLConnection con) [P zv4+
{ rD?L
for(int i=1;;i++) 2n><RZ/9
{ =@Dwlze
String header=con.getHeaderFieldKey(i); I4;A8I
if(header!=null) 3K&4i'}V
//responseHeaders.put(header,httpConnection.getHeaderField(header)); B!{d-gb
Utility.log(header+" : "+con.getHeaderField(header)); @J{m@ji{
else 6K cD&S/
break; 'ckQg=zPR
} ,y4I[[
} #Lsnr.80
O1%pxX'`S
sb:d>6
public void splitterStop() Y3kA?p0
{ r`&-9"+
bStop = true; ?1L.:CS
} 7*j (*
eD$M<Eu
L!/\8-&$P
} 4${jr\q]
V^y^ ;0I}[
')a(.f
/* T@}|zDC#
**FileAccess.java .)1_Ew
*//文件访问(定位，写) _(J&aY\
package NetFox; g&dPd7
import java.io.*; IcP)FB4
hLJM%on
_0+0#! J!
public class FileAccessI implements Serializable{ 6s,uXn
^@P1 JNe
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 I8oo~2Qw
RandomAccessFile oSavedFile; f)]%.>
long nPos; AV 8n(
_'4A|-9
NmK8<9`u
public FileAccessI() throws IOException 01!s"wjf
{ V)Z70J<'
this("",0); d]9U^iy
} Iff9'TE
'65LKD
I%|>2}-_U
public FileAccessI(String sName,long nPos) throws IOException ntNI]~z&
{ f}guv~K
oSavedFile = new RandomAccessFile(sName,"rw"); =U|N=/y#hJ
this.nPos = nPos; 1+b{}d
oSavedFile.seek(nPos); ' |-JWH
} e\O/H<
TJE\A)|>g
!+u"3;%h
public synchronized int write(byte[] b,int nStart,int nLen) .4.b*5
{ 5cx#SD&5/
int n = -1; }@if6(0
try{ Qf@I)4'
oSavedFile.write(b,nStart,nLen); &d7Z6P'`G
n = nLen; A^Kbsc
} +cb6??H
catch(IOException e) .q+0pj
{ zByT$P-
e.printStackTrace (); ceNix!P
} :Hxv6
.^J2.>.
MX>[^}n
return n; `1:{0p2q
} *<1r3!
@aJ!PV'ms
t6v/sZ{F
} ]v+31vdf:O
<dyewy*.L
12Y
/* 1+?^0%AC
**SiteInfoBean.java hsu{eyp
*/ fnx-s{c?
package NetFox; fdONP>K[E
UMX@7a,[3
(a9d/3M
public class SiteInfoBean { \.M*lqI
TLehdZ>^
bLt.O(T}
private String sSiteURL; //Site's URL boG_f@dv(
private String sFilePath; //Saved File's Path 1+?N#Fh
private String sFileName; //Saved File's Name ~ T>U
private int nSplitter; //Count of Splited Downloading File phO;c;y}
E*i#?u
hy|b6wF&
public SiteInfoBean() `est|C '+
{//nSplitter的缺省值为5 e<r,&U$
//default value of nSplitter is 5 F;^F+H
this("","","",5); e%W$*f
} yCCrK@{oo
F5S@I;
4&l10fR5
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) B=|cS;bM$3
{ /dnCwFXf
sSiteURL= sURL; {k rswh3
sFilePath = sPath; ;#Q%j%J
sFileName = sName; 3_A *$
this.nSplitter = nSpiltter; hMtf.3S7c
s+>:,U<A
n]he-NHP
} L5MzLE&~
sVex (X
b86}% FM
public String getSSiteURL() k{t`|BnPKB
{ I}R0q
return sSiteURL; P;4w*((} ~
} w&ak"GgV
[=~pe|8:
o6$4/I
public void setSSiteURL(String value) sH\5/'?
{ o.I6ulY8
sSiteURL = value; l&?ii68/
} )=Jk@yj8x
y( y8+ZT
B#9{-t3Vf
public String getSFilePath() 5h;+Ky!I
{ ~Jf{4*>y
return sFilePath; k1Q?'<`
} j&k6O1_
0Fu~%~#E$
4>J
public void setSFilePath(String value) 2WG>, 4W2
{ .YuJJJv
sFilePath = value; "Wx]RN:
} ~g.$|^,.O/
5xL~`-IA&v
0Lb4'25.
public String getSFileName() Jec'`,Y
{ K#.
return sFileName; zP<pEI
} R4-~jgzx
tsk)zP,<
++E3]X|
public void setSFileName(String value) qgrg CJ
{ $q 2D+_
sFileName = value; q:g2Zc'Y~W
} )vxUT{;sH
i&n'N8D@
O+ICol
public int getNSplitter() t%8d-+$
{ j1(D]Z=\
return nSplitter; o6p98Dpg
} ?Q&yEGm(
_Zr.ba
A@Dw<.&_I
public void setNSplitter(int nCount) sq'Pyz[[
{ i7ly[6{^pr
nSplitter = nCount; VH:]@x//{
} yDGVrc'
} GAAm0;
)rixMl &[
edPUG N
/* H$6`{lx,
**Utility.java r hfb ftw
*/ 0Zg%+)iy@
package NetFox; '}9JCJ
//aF5:Y#
Gw1@KKg
public class Utility { =)7s$ p
LcE+GC
"]G\9b)
public Utility() AQ='|%
{ 0P]E6hWgg
wm^J;<T[
.rf" (lM
} y8DhOlewQ
ZIF49`Y4TF
//线程睡眠 }[xs~!2F
public static void sleep(int nSecond) <'g:T(t
{ ?C/Te)
try{ JwXT%op9RP
Thread.sleep(nSecond); `[n("7,
} %$DI^yS
catch(Exception e) +[tP_%/r'^
{ uyY|v$FM
e.printStackTrace (); &@3H%DP}Ql
} |p-t%xDdr
} |ely|U. Tf
vEn4L0D
//日志 {,L+1h
public static void log(String sMsg) t N2Md}@e
{ wT{nu[=GH*
System.err.println(sMsg); ZGd!IghL
} p*P)KP
&/Q0
u#@Q:tnN_
public static void log(int sMsg) q?ix$nKOv
{ NhYLtw^u
System.err.println(sMsg); ny54XjtG,
} Ct%x&m:
} G2FXrkU
J^g!++|2P
dYgXtl=#j
/* T|6a("RL
**TestMethod.java &sd}ulEg`
*/ G}G#i`6o
package NetFox; W='>:H
U,.![TP
z+>}RT]
public class TestMethod { ,zTy?OQ
(zFi$
k Zq!&
public TestMethod() &EnuE0BD
{ ///xx/weblogic60b2_win.exe ^) s2$A:L
try{ L{`JRu
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); E)fglYWs2
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); s91JBP|B7
SiteFileFetch fileFetch = new SiteFileFetch(bean); UMcgdJB
fileFetch.start(); z.I9wQ]X[
} mOlI#5H
catch(Exception e){e.printStackTrace ();} '3 ^+{=q
RnDt)3
5O6hxcMjT
} ,1"KHv
_"w2Uq
"l*`>5Nn9
public static void main(String[] args) *v3]}g[<
{ ` 5C~
new TestMethod(); D= h)&
} =%BZ9,l
} ~7Tc$ "I
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