http断点续传简单实现（java)

亚文隆

级别: 经院学前班

发帖: 8

铜板: 1641

人品值: 95

贡献值: 0

交易币: 0

好评度: 8

信誉值: 0

金币: 0

所在楼道

只看楼主更多操作楼层直达

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)); MNe/H\
} ZyNgG9JL]
for(int i=0;i<nEndPos.length-1;i++) RF2I_4
{ I(BJ1 8F$
nEndPos = nStartPos[i+1]; "u~` ZV(
} H*<E5^#dw
nEndPos[nEndPos.length-1] = nFileLength; ke W7pN?
} 7)#JrpTj%
} #| gh
pd:YR;
lj&\F|-i
//启动子线程 r 56~s5A
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; ~e[qh+
for(int i=0;i<nStartPos.length;i++) mpwh=
{ OzC%6;6h
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), Gy["_;+xU
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), A~E S{Zkh
nStartPos,nEndPos,i); FPK=Tr:b
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); o+}1M
fileSplitterFetch.start(); hUvA;E(qD
} g6DIWMoO=h
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), i}>EGmv m
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 1 <T|
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", yCkc3s|DA;
nEndPos = " + nFileLength); e&ZTRgYdi
// fileSplitterFetch[nPos.length-1].start(); d<OdQvW.
t6-fG/Kc
ON!Fk:-
//等待子线程结束 >HwVP.~HN
//int count = 0; fYZd:3VdC
//是否结束while循环 j<Pw0?~s6
boolean breakWhile = false; yF|yZ{
#!TlalV
~qL/P 5*+
while(!bStop) tNZZCdB
{ L5d YTLY
write_nPos(); [\Aws^fD_
Utility.sleep(500); l>i:M#z&
breakWhile = true; 8?<J,zu@AV
zJ1M$U
c@]G;>o
for(int i=0;i<nStartPos.length;i++) D2o|.e<r
{ XD!}uDZ^
if(!fileSplitterFetch.bDownOver) W95q1f#7
{ 7}c[GC)F
breakWhile = false; r0&LjH&R
break; (C`nBiL<
} {4[dHfIy
} ^-~=U^2tC
if(breakWhile) i,Jz7OX
break; q:jv9eL.O
wLO"[,
0$yHO2 f
//count++; 6+s&%io4
//if(count>4) n@C#,v#^0
// siteStop(); NX;{L#lQ
} Pq-@waH3
@LU[po1I
]5ibg"{S
System.err.println("文件下载结束！"); q~AvxO
} vu*{+YpH
catch(Exception e){e.printStackTrace ();} 7n;a_Z0s$
} drwxrZt
=''*'a-P
Bz:Hp{7&
//获得文件长度 d|UH AX
public long getFileSize() ,gkWksl9
{ b-c6.aKf|
int nFileLength = -1; h"2^` )!u
try{ vj#m#1\f
URL url = new URL(siteInfoBean.getSSiteURL()); \ sz](X
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); %>O}bdSf
httpConnection.setRequestProperty("User-Agent","NetFox"); >E,/|K*
NLgeBLB
%hBw)3;l
int responseCode=httpConnection.getResponseCode(); 9]{Ss$W3x
if(responseCode>=400) 1&=2"
{ rX`fjS*C
processErrorCode(responseCode); P=9sP:[f6
return -2; //-2 represent access is error F*:H&,
} 9/#b1NGv
geqx":gpx9
`I|Y7GoUO
String sHeader; lL'K1%{+ \
LzB*d
e5ww~%,
for(int i=1;;i++) k5)IBO
{ QX(t@VP
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); un,W{*s8*
//Utility.log(in.readLine()); hH?ke(&=f
sHeader=httpConnection.getHeaderFieldKey(i); r9-)+R J
if(sHeader!=null) `E>o:tff
{ 9<Th: t|w
if(sHeader.equals("Content-Length")) Y$3liDeL=
{ " M&zW&
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); {N-*eV9#
break; :3}K$
} R*vfp?x
} >4T7DMy
else =D 5!Xq'|
break; Zk gj_
} lg jY\?
} iW?NxP
catch(IOException e){e.printStackTrace ();} kf)s3I/`(
catch(Exception e){e.printStackTrace ();} *b1NVN$
:\1vy5 _
F2=#\U$
Utility.log(nFileLength); 0@#d($'1?Z
%U97{y
_x7>d:C
return nFileLength; _1\H{x
} /Dk`?
LkXF~
??P>HVx
//保存下载信息（文件指针位置） *>j4tA{b@v
private void write_nPos() TrHUM4
{ @v}M\$N?
try{ .-p?skm=a
output = new DataOutputStream(new FileOutputStream(tmpFile)); j 2Jew
output.writeInt(nStartPos.length); y;LZX-Z-
for(int i=0;i<nStartPos.length;i++) ~eGtoEY
{ PF;`mdi-,
// output.writeLong(nPos); W4AFa>h
output.writeLong(fileSplitterFetch.nStartPos); YccD^w[`B
output.writeLong(fileSplitterFetch.nEndPos); lN::veD
} p:|p?
output.close(); N5fMMi(O
} 0OVxx>p/x
catch(IOException e){e.printStackTrace ();} `ve5>aw0_Y
catch(Exception e){e.printStackTrace ();} n11eJEtm
} %|?PG i@5
MqswYK-s
()@+QE$
//读取保存的下载信息（文件指针位置） zDA;FKZPp
private void read_nPos() ,W;2A0A?X
{ ^G(+sb[t
try{ #c2JWDH1F
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); uTUkRqtD!
int nCount = input.readInt(); N6S}u@{J~N
nStartPos = new long[nCount]; ;KW}F|
nEndPos = new long[nCount]; fYZ)5xnj
for(int i=0;i<nStartPos.length;i++) km!jxs
{ <UO'&?G
nStartPos = input.readLong(); +Tp>3Jh2
nEndPos = input.readLong(); \Ot,&Z k2
} p%y|w
input.close(); \RyW#[(
} A!!W\Jt
catch(IOException e){e.printStackTrace ();} t[^68]
catch(Exception e){e.printStackTrace ();} e?!A]2
} "zBYhZr
FDO$(&
D7b] ;Nf\
private void processErrorCode(int nErrorCode) Ja#ti y
{ o8ADAU"
System.err.println("Error Code : " + nErrorCode); c27A)`
} ,Tc598D
dJd(m&.|N
wloQk(T<W
//停止文件下载 xD<:'-ri>
public void siteStop() '0>w_ge4
{ ibskce{H
bStop = true; JN-wToOF
for(int i=0;i<nStartPos.length;i++) V,)bw
fileSplitterFetch.splitterStop(); F2RU7o'f.
:Sd iG=t
?Dk&5d^d
} x0_$,Tz@
} }*I:0"WH
//负责部分文件的抓取 sKI{AHJ?X
**FileSplitterFetch.java rXlJW]i
*/ W-+~r
package NetFox; \>*B
ril4*$e7^\
&]Q\@;]Aq
import java.io.*; StJ&YYdD
import java.net.*; \sZ!F&a~
U(cV#@Y
A296f(
public class FileSplitterFetch extends Thread { 4r'f/s8"#
qkN{l88
B'Ll\<mq@
String sURL; //File URL c>%+y+b{
long nStartPos; //File Snippet Start Position V.*0k~
long nEndPos; //File Snippet End Position xr*hmp1
int nThreadID; //Thread's ID `Al( AT(p
boolean bDownOver = false; //Downing is over 3jB5F0^r1
boolean bStop = false; //Stop identical k-&fPEjG
FileAccessI fileAccessI = null; //File Access interface 2'zYrdem
+5:oW~ ;
IirXF?&t
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException yBwgLn
{ Td !7Rx _
this.sURL = sURL; g~JN"ap
this.nStartPos = nStart; syYe0~
this.nEndPos = nEnd; <k0$3&D
nThreadID = id; s<t*g]0`/
fileAccessI = new FileAccessI(sName,nStartPos);//定位 9$pQ|e0tJ
} ^%V^\DK
El$yM.M"
:NJ(QkTZv
public void run() xM3T7PV9
{ 3~7X2}qU
while(nStartPos < nEndPos && !bStop) 7]w]i5
{ 11s*C #
D@5AI ](
~al4`:rRx1
try{ Rh:edQ#
URL url = new URL(sURL); <V-D
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); GDgq 4vfj
httpConnection.setRequestProperty("User-Agent","NetFox"); dd +%d
String sProperty = "bytes="+nStartPos+"-"; %\5d?;
httpConnection.setRequestProperty("RANGE",sProperty); z+>FKAF
Utility.log(sProperty); '7UW\KEB[}
al9L+ruR
;-:Nw6 E
InputStream input = httpConnection.getInputStream(); n-P)X<\
//logResponseHead(httpConnection); I$7#Z!P6|
jU~ !*]
4PwjG;!K
byte[] b = new byte[1024]; $y\\?
int nRead; ^x8yWbrE
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) tiI:yq0
{ $d]3ek/
nStartPos += fileAccessI.write(b,0,nRead); +5|wd6
//if(nThreadID == 1) J_]B,' 6
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); h#ogL-UU
} 'w^Md
Hp2ysU
"Cz8nG
Utility.log("Thread " + nThreadID + " is over!"); '+6SkZ
bDownOver = true; 6tC0F=
//nPos = fileAccessI.write (b,0,nRead); ai!zb2j!E
} Hy _ (
catch(Exception e){e.printStackTrace ();} 8cV3VapF
} Flrpk`4
} HB}!Lf#*P
.""?k[f5Q
$wgHaSni
//打印回应的头信息 Sz.sX w;
public void logResponseHead(HttpURLConnection con) |;XkU`G
{ uTgvMkO
for(int i=1;;i++) MCBZq\c
{ Dp)5u@I
String header=con.getHeaderFieldKey(i); o(=\FNe
if(header!=null) %s}c#n)N
//responseHeaders.put(header,httpConnection.getHeaderField(header)); %|&WcpQR
Utility.log(header+" : "+con.getHeaderField(header)); 9ZbT41
else .DzFtc
break; W+v7OSd92
} ZK1H%&P=R
} _O76Aw-@l
Sm@T/+uG:
n-/{H4\
public void splitterStop() cO]_5@#f'8
{ $e bx
bStop = true; |yqL0x0\l
} 'G6g yO/K
I\%a<
S?ypka"L
} '&XL|_Iq
w}wABO
}Zs y&K
/* '<}N`PS#N
**FileAccess.java /i'dhiG
*//文件访问(定位，写) `QpkD8
package NetFox; T$p!IRPt
import java.io.*; kj$Ks2!W
0X.(BRI~6p
LHQ$0LVt>T
public class FileAccessI implements Serializable{ !'y9/
2pKkg>/S
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 :gD=F&V
RandomAccessFile oSavedFile; rb"J{^
long nPos; =;hz,+
it Byw1/
us/}_r74N*
public FileAccessI() throws IOException ULqFJ*nla
{ ljr?Z,R4
this("",0); %25GplMT
} xL-]gwq
.uo9VL<
V 6DWYs>
public FileAccessI(String sName,long nPos) throws IOException zSJSus
{ J>@T'#
oSavedFile = new RandomAccessFile(sName,"rw"); )=~OP>7B
this.nPos = nPos; c#-o@`Po
oSavedFile.seek(nPos); v- 793pr
} oGtz*AP%
~Ox !7Lp
}Kt`du=
public synchronized int write(byte[] b,int nStart,int nLen) -rn%ASye
{ QD2;JI2
int n = -1; ]0Y5 Z)3:z
try{ O,a1?_m8
oSavedFile.write(b,nStart,nLen); -2o_ L?
n = nLen; xaPaK-
} [:CV5k~xc
catch(IOException e) S2;u!f
{ 8)Z)pCN
e.printStackTrace (); +D3w2C
} bS1?I@
_Se0,Uns
(uW$ch@2K
return n; "!g}Q*
} yi29+T7j4S
UrMEL;@g
n+'gVEBA
} IqA'Vz,lL
b.N$eJlQ&
[}mx4i
/* JZl"k
**SiteInfoBean.java i9RAbtQ}
*/ ;2k!KW@
package NetFox; y7X2|$9z-
4X}.aZO&b
^\(<s
public class SiteInfoBean { ;4%Co)Rw
e+TSjm
^t2b`n60
private String sSiteURL; //Site's URL 6E)emFkQ
private String sFilePath; //Saved File's Path TJO?BX_9
private String sFileName; //Saved File's Name GJ9'i-\*\
private int nSplitter; //Count of Splited Downloading File `K%f"by
a'Vz|SG
?LwBF;Y
public SiteInfoBean() H(QbH)S$6
{//nSplitter的缺省值为5 ^oLMgz
//default value of nSplitter is 5 at )m*
this("","","",5); X21k7 Ls
} B-1Kfc
CVAX?c{
ZL7#44
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) t+l{D#?a
{ b_&KL_vo{|
sSiteURL= sURL; ] >4CBm$
sFilePath = sPath; Fd1t/B,
sFileName = sName; |uIgZ|7[
this.nSplitter = nSpiltter; ,SF>$ .
)Y](Mj!D
EK%J%NY
} ~_]i'ii8
3nbTK3,
l:.q1UV
public String getSSiteURL() Ai*+LSG
{ HOr.(gL!
return sSiteURL; hU~up a<dD
} 4}r.g0L
h`@z61UI
nw
public void setSSiteURL(String value) wqasI@vyu
{ kZK1{
sSiteURL = value; )4;$;a1
} ?X'l&k>
sLOkLz"x
cl{kCSZo.z
public String getSFilePath() Swxur+hfH
{ -%_vb6u
return sFilePath; -\[&<o@/D
} nkO4~p
n.b_fkZNr
sHPK8Wsg
public void setSFilePath(String value) b^'>XT~1J&
{ (o2.*x
sFilePath = value; d9.I83SS
} w\}Q.$@
wu;^fL
M!b-;{;'
public String getSFileName() W5(.Hub}
{ m0,TH[HWGF
return sFileName; ~(-df>
} tpn.\z%
KPxf
qM(@wFg
public void setSFileName(String value) Rebo.6rG
{ _X~xfmU
sFileName = value; !a7YM4D
} Fvr$K*u
^5Ob(FvU
4CK$W`V
public int getNSplitter() A,;[9J2\&
{ m~`f0
return nSplitter; 4Jk[X>I~
} o<L=l Q
_}l7f
X_(n
public void setNSplitter(int nCount) jMP;$w
{ IQyw>_~]
nSplitter = nCount; m/"}Y]n!
} <.U(%`|
} /&o<kY
|5(un/-C
4p&YhV7j)o
/* uX8G<7O^
**Utility.java }_h2:^n
*/ yhxZ^(I
package NetFox; Gf<%bQE
;edt["Eu
7xfN}iHG
public class Utility { zC WN,K`
MmW]U24s
%5Zhq>
public Utility() R[!%d6jDE
{ B18?)LA
nzl3<Ar
8M6Qn7{L
} c#T0n !}
x-HR[{C
//线程睡眠 %!V=noo
public static void sleep(int nSecond) T-.Bof(?w
{ ^dRgYi"(A
try{ wQrD(Dv(yA
Thread.sleep(nSecond); wiM-TFT~
} 7DB!s@"
catch(Exception e) Yzih-$g
{ VRvX^w0
e.printStackTrace (); vve[.Lud'
} f= 33+8I
} B0ZLGB
f4+}k GJN
//日志 d^G5Pq
public static void log(String sMsg) =f=,YcRn+
{ `E5vO1Pl
System.err.println(sMsg); FSyeDC^@
} giu8EjzK
1fcyGZq
OIrr'uNH
public static void log(int sMsg) l~$Od jf
{ #yR@.&P
System.err.println(sMsg); H >1mi_1
} ~.TKzh'eB
} Ku;8Mx{
<'92\O
=d1i<iw?-
/* k4BiH5\hA
**TestMethod.java IjrjLp[z$
*/ AGgL`sP
package NetFox; .6y(ox|LL
U66zm9 3&
?KXgG'!!
public class TestMethod { o>ZlA3tv
=f-.aq(G/
mx")cGGQ
public TestMethod() nY=]KU
{ ///xx/weblogic60b2_win.exe a3(q;^v
try{ H_+!.
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); Tp fC
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); }Oh@`xTxt
SiteFileFetch fileFetch = new SiteFileFetch(bean); TF;}NQ
fileFetch.start(); '/K-i.8F
} 7|$ H}$
catch(Exception e){e.printStackTrace ();} sp&)1?!M
P1}Fn:Xe%7
Odj4)
} 7d'gG[Z^^
<P)0Yu
zFGZ;?i
public static void main(String[] args) SBqx_4}
{ *<T,Fyc|
new TestMethod(); K)8N8Js(
} 8A3!XA
} eWwI@ASaA
点击下载更多相关资料