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)); *oh,Va
} dL1{i,M
for(int i=0;i<nEndPos.length-1;i++) M pz9}[`3g
{ ZpwFC7LW
nEndPos = nStartPos[i+1]; !<h-2YF<M
} XWB#7;,R
nEndPos[nEndPos.length-1] = nFileLength; _?Ly7*UML
} 90=gP
} A`I1G9s
A#F6~QX(.9
u3jLe=Y'\
//启动子线程 ++|e z{
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; btDTC9O
for(int i=0;i<nStartPos.length;i++) Izfq`zS+\s
{ O4^' H}*
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), b: I0Zv6
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), tCj\U+;
nStartPos,nEndPos,i); |uJjO>8]|
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); nbDjoZZ4
fileSplitterFetch.start(); IY@N
} ny<D1>{90
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), M'NOM>8
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); &o`LT|*m
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 1CUI6@Cz)
nEndPos = " + nFileLength); @G|z_
// fileSplitterFetch[nPos.length-1].start(); 8K\S]SZ
ogdgLTi
a{.-qp
//等待子线程结束 }C JK9*Z
//int count = 0; 0/~{,
//是否结束while循环 oSO~72
boolean breakWhile = false; g(o^'f
WjvgDNk
6x16?x
while(!bStop) x*:"G'zT
{ u*T#? W?
write_nPos(); <.lt?!.ZH
Utility.sleep(500); :4Y5
breakWhile = true; R{9G$b1Due
^jk-GRD*
rFW,x_*_vP
for(int i=0;i<nStartPos.length;i++) WvcPOt8Bp>
{ QghL=
if(!fileSplitterFetch.bDownOver) @Fb 2c0?Y
{ D@ BP<
breakWhile = false; \.=,}sV2Z
break; L~Xzo
} :M@#.
} c$;Cpt@-j
if(breakWhile) byk9"QeY\
break; Se!B,'C%
0.^67'
aOmQ<N]a
//count++; %^iBTfq2hc
//if(count>4) aM\Ph&c7e'
// siteStop(); |O*?[|`H
} 5^N`~
WG&WPV/p
VE^IA\J x
System.err.println("文件下载结束！"); X/D% cQ6
} NLev(B:OQH
catch(Exception e){e.printStackTrace ();} O7f"8|=HX
} *3y_FTh8ra
YG#{/;^nm)
kM76?M
//获得文件长度 |u[@g`Z
public long getFileSize() Fw%S%*B8g
{ e#ne5
int nFileLength = -1; 1@q"rPE^
try{ 6^z):d#u
URL url = new URL(siteInfoBean.getSSiteURL()); !*,m=*[3
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); N1dM,H
httpConnection.setRequestProperty("User-Agent","NetFox"); E$4Ik.k
T?{F7
i >BQRbU
int responseCode=httpConnection.getResponseCode(); p'=XW#2 >
if(responseCode>=400) R1Q~UX]d=
{ + ;B K|([#
processErrorCode(responseCode); F^cu!-L
return -2; //-2 represent access is error w#>CYP`0k6
} OB+QVYk"
J/c5)IB|
.R&jRtb/E
String sHeader; ^B(:Hv}G(:
Z07SK 'U
oox;8d4}y
for(int i=1;;i++) ezhK[/E=
{ }t1J`+x%
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ({hW
//Utility.log(in.readLine()); Ka8Bed3
sHeader=httpConnection.getHeaderFieldKey(i); KY9@2JG
if(sHeader!=null) &hIr@Gi@ch
{ -8sB\E
if(sHeader.equals("Content-Length")) _TVKvRh
{ if+97^Oy
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); b2hXFwPe
break; Ne}x(uRn
} h?vt6t9
} bO }9/Ay
else rG'W#!^*
break; #mRT>]di`D
} *,e`.
} ifadnl26 s
catch(IOException e){e.printStackTrace ();} Gp1?drF6
catch(Exception e){e.printStackTrace ();} eMUt%zvb
BBj>ML\X
3Sn# M{wH
Utility.log(nFileLength); w[/m:R?eX
DhiIKd9W
lR5k1J1n
return nFileLength; 'CvV Ktk
} 2Gn26L5
B\quXE)
1j!{?t?
//保存下载信息（文件指针位置） ;sY n=r
private void write_nPos() k}e~xbh-y
{ #6 M3BF
try{ 9*? i89T
output = new DataOutputStream(new FileOutputStream(tmpFile)); |GP1[Q{
output.writeInt(nStartPos.length); D3C3_ @*
for(int i=0;i<nStartPos.length;i++) G]gc*\4
{ pUeok+k_
// output.writeLong(nPos); p u[S
output.writeLong(fileSplitterFetch.nStartPos); G4J)o?:m@
output.writeLong(fileSplitterFetch.nEndPos); DP!~WkU~
} U;FJSy
output.close(); ?PU7xO;_
} J|DY /v
catch(IOException e){e.printStackTrace ();} LDj*~\vsq
catch(Exception e){e.printStackTrace ();} 1raq;^e9
} luCwP
7~nuFJaTI
vm8ER,IW)
//读取保存的下载信息（文件指针位置） 6Vu)
private void read_nPos() VB}^&{t)!
{ A%.ZesjAx
try{ :[ll$5E.
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); K8fC>iNbH
int nCount = input.readInt(); uS5ADh
nStartPos = new long[nCount]; /2:s g1
nEndPos = new long[nCount]; 0uJ??4N9
for(int i=0;i<nStartPos.length;i++) l|K$6>80
{ &Yd6w}8
nStartPos = input.readLong(); B$_-1^L e
nEndPos = input.readLong(); @ [%K D
} !iU$-/,1e
input.close(); x+,:k=JMT
} M,oRi;V
catch(IOException e){e.printStackTrace ();} V6fJaZ
catch(Exception e){e.printStackTrace ();} oe[f2?-
} 8Bx58$xRq
F?b"Rv
pLtK:Z
private void processErrorCode(int nErrorCode) 3shd0q<
{ ricL.[v9S
System.err.println("Error Code : " + nErrorCode); 'm.+S8
} rYrvd[/*&(
FM<`\d'
)&93YrHgC
//停止文件下载 a.fdCI]%
public void siteStop() YhL^kM@c
{ L`"V_ "Q#0
bStop = true; zB'_YwW
for(int i=0;i<nStartPos.length;i++) O[F
fileSplitterFetch.splitterStop(); d^d+8R
UD ;UdehC
z+<ofZ(.
} aq- |
} TEi1,yc
//负责部分文件的抓取 =-/sB>-C
**FileSplitterFetch.java lg*?w/JX+
*/ ]E#W[6'VtB
package NetFox; iKG,"
z[0tM&pv
g1)ZjABV
import java.io.*; bfI= =
import java.net.*; $>rKm
uj+{ tc
^;wz+u4^l
public class FileSplitterFetch extends Thread { \f@obp
Bv#?.0Ez;
-@.FnFa
String sURL; //File URL a&u!KAQ
long nStartPos; //File Snippet Start Position ywA7hm
long nEndPos; //File Snippet End Position L9d|7.b
int nThreadID; //Thread's ID -?NAA]P5c@
boolean bDownOver = false; //Downing is over Ugme>60`'k
boolean bStop = false; //Stop identical kc<5wY_t
FileAccessI fileAccessI = null; //File Access interface $4hi D;n
gi$'x^]#
v1=N?8Hz1
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException #szIYyk
{ M9?f`9
this.sURL = sURL; WAJKP"
this.nStartPos = nStart; d '\^S}
this.nEndPos = nEnd; nK#%Od{GF
nThreadID = id; iqKs:v@+x
fileAccessI = new FileAccessI(sName,nStartPos);//定位 S_38U
} xXSfYW
<,Mf[R2N>
p$cb&NNh*H
public void run() 3gtKD9RL:
{ $GYy[8{:V
while(nStartPos < nEndPos && !bStop) m$7C{Mr'
{ 8Yo;oHk7
MHJRBn{}
03"FK"2S
try{ XW~a4If
URL url = new URL(sURL); Hz%<V*\{
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); D;[%*q*
httpConnection.setRequestProperty("User-Agent","NetFox"); tJA"BP3f
String sProperty = "bytes="+nStartPos+"-"; Y(gai?
httpConnection.setRequestProperty("RANGE",sProperty); z<gII~%
Utility.log(sProperty); u#NX`_
N1"p ;czK
{7%(m|(
InputStream input = httpConnection.getInputStream(); Q:Ma3El\
//logResponseHead(httpConnection); g!OcWy)7
t%Bh'HkG
UhJ!7Ws$
byte[] b = new byte[1024]; `qRyh}Ax"
int nRead; q*kLi~Oe
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) q/ (h{cq
{ $k`j";8uR
nStartPos += fileAccessI.write(b,0,nRead); =Aw`0
//if(nThreadID == 1) }aQ*1Vcj
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); +O^} t
} P)LOAe1'
3*\hGt,ZP
.&I!2F
Utility.log("Thread " + nThreadID + " is over!"); X*9-P9x(6
bDownOver = true; {ft |*
//nPos = fileAccessI.write (b,0,nRead); ^f9@=I
} 9$D}j"
catch(Exception e){e.printStackTrace ();} <p-@XzyE
} q_98=fyE6
} pl$wy}W-
1 1(GCu
&3 Ki
//打印回应的头信息 *9aI\#}
public void logResponseHead(HttpURLConnection con) Rt5pl,Nf
{ T#i~/
for(int i=1;;i++) 7|jy:F,w%
{ z?F`)}
String header=con.getHeaderFieldKey(i); :))&"GY
if(header!=null) 2EYWX!Bx
//responseHeaders.put(header,httpConnection.getHeaderField(header)); J:O&2g"g
Utility.log(header+" : "+con.getHeaderField(header)); #lMC#Ld
else >[:qJ|i%
break; P1Eg%Y6
} Q2:rWE{K!
} 5evk_f
)>"pm{g2
J^S!GG'gb
public void splitterStop() ,Q.[Lc=w
{ QpRk5NeLe
bStop = true; 8&3&^!I
} GG-b)64h`
RLzqpE<rJ
(ti!Y"e2
} +5 gX6V\
g3^:)$m
Q7{{r&|t&
/* mAET`B "
**FileAccess.java s@GE(Pu7
*//文件访问(定位，写) :ln?PT
package NetFox; 7oc Ng
import java.io.*; /-t!)_zvw
2I& dTxIa
X.FoX
public class FileAccessI implements Serializable{ 0c1=M|2
9I$}=&"
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 BwGOn)KL
RandomAccessFile oSavedFile; EyA(W;r.
long nPos; B&<5VjZ\
+nim47
*5?Qam3
public FileAccessI() throws IOException XD|Xd|/ {
{ Cbl>eKw
this("",0); Z;BEUtR c
} jTZi< Y:bB
@<X[,Mj
q?)5yukeF
public FileAccessI(String sName,long nPos) throws IOException _qpIdQBo
{ x]?V*Jz
oSavedFile = new RandomAccessFile(sName,"rw"); }NRt:JC
this.nPos = nPos; qm'@o -[
oSavedFile.seek(nPos); y4aT-^C'
} mG\9Qkom|
59v=\; UI
RlU?F
public synchronized int write(byte[] b,int nStart,int nLen) ?I:_FT
{ r'_#rl
int n = -1; vpOGyvI
try{ SG&H^V8
oSavedFile.write(b,nStart,nLen); i_+e&Bjd4j
n = nLen; xDSiTp=)O
} lw?C:-m
catch(IOException e) RBg2iG$8|
{ ;`kOFg#`)c
e.printStackTrace (); "LW\osjen
} TDy)A2Z
zf5%|7o
sSD&'K=lq
return n; w^n&S=E E~
} RdL5VAD
,?Vxcr
xaV3N[Zd
} !=yO72dgLY
\$t{K
p]Qe5@NT
/* e8egxm
**SiteInfoBean.java Qy=tkCN
*/ %u<r_^w5
package NetFox; ;j(*:Nt1
wN6sica|
`/wXx5n5<
public class SiteInfoBean { ?duw0SZ
B>z^W+Unyn
sk0/3X*Q%
private String sSiteURL; //Site's URL Q&%gpa).W
private String sFilePath; //Saved File's Path 7)Tix7:9S;
private String sFileName; //Saved File's Name \,:7=
private int nSplitter; //Count of Splited Downloading File #>BC|/P}
0TICv2l!
,'l.u?SKyd
public SiteInfoBean() 20`XklV
{//nSplitter的缺省值为5 6(1 &6|o3
//default value of nSplitter is 5 ,.gJ8p(0x
this("","","",5); !VrBoU4<d
} !ueh%V Ky
|L-- j
C)9-{Yp
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) oW(8bd)
{ 0&r}'f?
sSiteURL= sURL; \S~<C[P
sFilePath = sPath; CaoQPb*
sFileName = sName; f)Z'#[A*t7
this.nSplitter = nSpiltter; T).}~i;!
(.{."
uHDUuK:Ur
} lb"T'}q
I4c%>R
L9whgXD
public String getSSiteURL() *1>Tc,mb
{ WFqOVI*l
return sSiteURL; ~n/:a
} : R8+jO
bs?4|#[K
jar?"o
public void setSSiteURL(String value) R/^;,.
{ W}wd?WIps
sSiteURL = value; 91#n Aj%
} rj5)b:c}
BTE&7/i21
rmI@ #'
public String getSFilePath() }yCgd 5+_
{ mFIIqkUAL
return sFilePath; M49Hm[0(
} >rh<%55P`
er!+QD,EM
uQWd`7
public void setSFilePath(String value) .+^o{b
{ $g#d1u0q
sFilePath = value; rO1.8KKJ
} r1$x}I#Zv
<5sfII
-%t8a42
public String getSFileName() 6AmFl<
{ )#Y:Bj7H@2
return sFileName; ;Y(~'KF
} +T7FG_
,k/<Nv;
An !i
public void setSFileName(String value) +Nka,C^O"
{ i"hn%u$V
sFileName = value; nSU7,K`PM
} u\UI6/
5d82Ms
E__A1j*gd
public int getNSplitter() Wy$Q!R=i
{ Cd7d-'EQn
return nSplitter; k:zGv
} Xc]Q_70O
;V1e>?3
e9?y0vT//
public void setNSplitter(int nCount) yAVt[+0
{ ;4]l P
nSplitter = nCount; <4Cy U j
} W-ECmw(
} woK?td|/
ia/_61%
p&;,$KDA
/* <i1P~
**Utility.java <8/lHQ^\)
*/ <3Hu(Jx<O
package NetFox; aw/5#(1R
Tk4"qGC.
=").W\,
public class Utility { bjq2XP?LL
u@zBE? g
$(%t^8{a~G
public Utility() ^zaN?0%S33
{ $rE_rZ+]="
v|mZcAz
hC=="4 -
} m,]M_y\u
7gQ~"Q
//线程睡眠 b}r3x&)
public static void sleep(int nSecond) [t`QV2um
{ \6${Na'\
try{ ) 4'@=q
Thread.sleep(nSecond); ysiBru[u
} ];go?.*C
catch(Exception e) "$BWP
{ WChJ <[]W
e.printStackTrace (); -.E<~(fad
} Z`b{r;`m8
} F 'U Gp
u-. _;
//日志 5q?ZuAAA
public static void log(String sMsg) <[7.+{qfW
{ fm\IQqIK%
System.err.println(sMsg); aNCIh@m~
} fW4N+2
Hd)4_ uBt
y85/qg)H^
public static void log(int sMsg) #\$R^u]!
{ m>6,{g)
System.err.println(sMsg); puz~Rfn#*
} Vj"B#
} e? fFh,a
!285=cxz
i4N'[ P}
/* X&6p_Lo
**TestMethod.java fgP_NYfOj
*/ MI@id
package NetFox; m$:o+IH/
,P<n\(DQ
Jx@3zl
public class TestMethod { Nd*zSsVlq
oToUpkAI
-lm\~VZT3
public TestMethod() ;X!sTs
{ ///xx/weblogic60b2_win.exe {ls$#a+d
try{ BXVmt!S5F
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Z*QsDS
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); V3-5:z
SiteFileFetch fileFetch = new SiteFileFetch(bean); 5dS5,
fileFetch.start(); ZO+c-!%[(
} EOjo>w>
catch(Exception e){e.printStackTrace ();} 2*5Z| 3aX
ayuj)]b
a="Z]JGk
} m6)8L?B
1_!*R]aq
mV} peb
public static void main(String[] args) |Gb"%5YD
{ HP2]b?C
new TestMethod(); ` IiAtS
} U&|=dH]-
} ";cWK29\f
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