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)); qKXn=J/0tA
} s,=^V/c
for(int i=0;i<nEndPos.length-1;i++) 7va%-&.&t
{ fk_i~K
nEndPos = nStartPos[i+1]; .l!Z=n|
} ^ TS\x/P
nEndPos[nEndPos.length-1] = nFileLength; hCrgN?Mz
} uq_SF.a'v
} /:)4tIV
*@Z'{V\
Z9y:}:j"
//启动子线程 {zcjTJ=Zt8
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; .j },
for(int i=0;i<nStartPos.length;i++) hB4.tMgZ
{ bBf+z7iyc
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), |m%&Qb
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), g}7B0 yo
nStartPos,nEndPos,i); 0%GWc}o
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); uB?YJf .T@
fileSplitterFetch.start(); TnrMR1Zx
} JP]K\nQx'
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), H+Wd#7l,
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); .0 K8h:I
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", 0 N(2[s_A
nEndPos = " + nFileLength); -$rfu
// fileSplitterFetch[nPos.length-1].start(); {_JLmyaerZ
&+sN=J.x
=G`m7!Q)
//等待子线程结束 qi$8GX=~r
//int count = 0; r_",E=e
//是否结束while循环 ~*qGH
boolean breakWhile = false; E*$:~w
spf}{o
,o`qB81
while(!bStop) RL%{VE
{ OkM>
write_nPos(); -llujB%;,e
Utility.sleep(500); ~Hq 2'
breakWhile = true; l#Tm`br
r]yq #T`z
,^(T^ -
for(int i=0;i<nStartPos.length;i++) 3y!CkJKv
{ YY9q'x,w
if(!fileSplitterFetch.bDownOver) TFhj]r^{
{ UTz;Sw?~hw
breakWhile = false; U8dwb
break; S70ERRk
} BsAglem
} @UA>6F
if(breakWhile) :5(TOF
break; LLMkv!%D
Y+N87C<
sr\MQ?\fB
//count++; DmYm~hzJ
//if(count>4) `i}\k
// siteStop(); Mm5l>D'c
} *VpQ("
X*sF-T$.
fAK
System.err.println("文件下载结束！"); ?'%&2M zM
} }5gQZ'ys'
catch(Exception e){e.printStackTrace ();} )\e_I\-
} 9/{g%40B^
O=fT;&%.
.'4*'i:
//获得文件长度 TF'ssD
public long getFileSize() 5]{YERa'
{ C'Ymz`iQ
int nFileLength = -1; `:2C9,Xu
try{ Vo\d&}Q
URL url = new URL(siteInfoBean.getSSiteURL()); +$9w[ARN+
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); }K/[3X=B
httpConnection.setRequestProperty("User-Agent","NetFox"); -vMP{,
'K`)q6m
#X)s=Y&5!T
int responseCode=httpConnection.getResponseCode(); V3-LVgM%
if(responseCode>=400) a'|0e]
{ k;)L-ge9
processErrorCode(responseCode); \l:n
return -2; //-2 represent access is error f?]cW h%
} )z aMycW
Vq*p?cF .
Ai/#C$MY$
String sHeader; (GeJBw,Q
NT/}}vES
qAU]}Et/
for(int i=1;;i++) f7`y*9^
{ sU8D;ML7
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); \nLO.,
//Utility.log(in.readLine()); \3KCZ
sHeader=httpConnection.getHeaderFieldKey(i); `@ObM[0p(
if(sHeader!=null) {>i'Pb0mG|
{ v4&*iT
if(sHeader.equals("Content-Length")) f; 22viE
{ ~6OdPD
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); NENbr$,G
break; {\%x{
} .VI2V-Q
} Un<~P@T%
else 'HC4Q{b`
break; 4fN<pG,
} jQc0_F\
} ?O_;{(F_
catch(IOException e){e.printStackTrace ();} H1X6f7`
catch(Exception e){e.printStackTrace ();} Y-Z.AA,
l-mUc1.S
q3;HfZ
Utility.log(nFileLength); V7&L+]!
G~_dSa@g G
u^`B#b'
return nFileLength; # OJD<=")
} \dP2xou=
rsP1?Hxq
zRz3ot,|
//保存下载信息（文件指针位置） ci$o~b6V
private void write_nPos() q H+~rj
{ |ey6Czm
try{ 7==Uoy*O
output = new DataOutputStream(new FileOutputStream(tmpFile)); 4g6d6~098;
output.writeInt(nStartPos.length); eX=W+&lj
for(int i=0;i<nStartPos.length;i++) AttDD{Ta
{ Q%85,L^U
// output.writeLong(nPos); lwK Au!l
output.writeLong(fileSplitterFetch.nStartPos); I|p(8R!
output.writeLong(fileSplitterFetch.nEndPos); nJ6bC^*)U
} ^rx]Y;
output.close(); UCl,sn
} Q4UaqiL
catch(IOException e){e.printStackTrace ();} O*30|[
catch(Exception e){e.printStackTrace ();} N~a?0x
} d9E:LZy
YS;Ql\4
nY6^DE2f
//读取保存的下载信息（文件指针位置） gn'. 9";j
private void read_nPos() 1(m89C[
{ <%|2yPb]
try{ ~*H!zKIx
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); :HwB+Bjy
int nCount = input.readInt(); 9XS'5AXN
nStartPos = new long[nCount]; |n~-LH++
nEndPos = new long[nCount]; pN?
for(int i=0;i<nStartPos.length;i++) VG)kPKoi
{ .aNy)Yu8
nStartPos = input.readLong(); @k6>&PS
nEndPos = input.readLong(); O)W1.]GMbf
} dC)@v]#h
input.close(); GUMO;rZs
} ?-6oh~W<
catch(IOException e){e.printStackTrace ();} mio\}SA
catch(Exception e){e.printStackTrace ();} Ru2kC} Dx!
} ;Lz96R@}
@c5TSHSL.
LA1UD+S
private void processErrorCode(int nErrorCode) ^f@EDG8
{ ^'#vUj:"
System.err.println("Error Code : " + nErrorCode); @dw0oRF
} O{Wy;7i
kvKbl;<&#
z`'{l{
//停止文件下载 @'dtlY5;
public void siteStop() I>:M1Yc0
{ f~t*8rG~m
bStop = true; WOquG
for(int i=0;i<nStartPos.length;i++) RHeql*`
fileSplitterFetch.splitterStop(); $O=m/l$
^hLAMaR
`O*+%/(
} yyG:Kl
} G9d@vu
//负责部分文件的抓取 E7ixl~
**FileSplitterFetch.java U }xRvNz
*/ tvavI9
package NetFox; '`^`NI`
iku) otUc
aO6w:IO
import java.io.*; {4\(HrGNk
import java.net.*; .t$~>e .
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bfhap(F~(e
public class FileSplitterFetch extends Thread { ~:v" TuuK
n YWS'i@
]|'Mf;
String sURL; //File URL Qn6'E
long nStartPos; //File Snippet Start Position i#=s_v8
long nEndPos; //File Snippet End Position ?o?~Df&
int nThreadID; //Thread's ID "1yXOy^2
boolean bDownOver = false; //Downing is over Fn1|Wt*
boolean bStop = false; //Stop identical 1r'skmxq
FileAccessI fileAccessI = null; //File Access interface "'~55bG
8 Zhx&
>Ta|#]{
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException {L4ta~2/T
{ ]gx]7
this.sURL = sURL; CM|?;PBuv
this.nStartPos = nStart; c/%i,N\5
this.nEndPos = nEnd; cba~
nThreadID = id; 6O>NDTd%
fileAccessI = new FileAccessI(sName,nStartPos);//定位 -lAX-W0
} h`;w/+/Zr
?%(:
j&(aoGl@
public void run() $GB/}$fd&
{ AT+7!UGL
while(nStartPos < nEndPos && !bStop) 3]$qY_|7
{ .0}]/%al
tUaDwIu#
2= S;<J
try{ Db3#;
URL url = new URL(sURL); <xv@us7
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 3+ JkV\AF
httpConnection.setRequestProperty("User-Agent","NetFox"); H$^IT#
String sProperty = "bytes="+nStartPos+"-"; -T$%MX
httpConnection.setRequestProperty("RANGE",sProperty); Xt& rYv
Utility.log(sProperty); .?|pv}V
^M_0M
A0~uv4MC
InputStream input = httpConnection.getInputStream(); g]%sX6T
//logResponseHead(httpConnection); .EpcMXT%
mO%F {'
qy|[V
byte[] b = new byte[1024]; FX}kH]
int nRead; =Kqb V{!
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) <#HQU<
{ rY yB"|
nStartPos += fileAccessI.write(b,0,nRead); Vz[tgb]-
//if(nThreadID == 1) X+dLk(jI`u
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); 1g<jr.
} -!4Mmp"2@u
1<766
h0ml#A`h
Utility.log("Thread " + nThreadID + " is over!"); U|yXJ.Z3
bDownOver = true; F`))qCgg]
//nPos = fileAccessI.write (b,0,nRead); F8Y_L\q
} dPvRbwH<
catch(Exception e){e.printStackTrace ();} M5\$+Tu
} 'ONCz
} p`N+9t&I4
fXD9w1
>JVdL\3
//打印回应的头信息 ~$w9L998+
public void logResponseHead(HttpURLConnection con) zp.-=)D4e
{ #O<,
for(int i=1;;i++) ;D'6sd"
{ >x'R7z23
String header=con.getHeaderFieldKey(i); N5K\h}'%
if(header!=null) Z8 eB5!$
//responseHeaders.put(header,httpConnection.getHeaderField(header)); IPHZ~'M
Utility.log(header+" : "+con.getHeaderField(header)); ,y5,+:Y ~
else P-]u&m/6
break; bSJ@ 5qS
} ,#?iu?i/
} [0>I6Jl
Z/G`8|A
7F$G.LhMw
public void splitterStop() 2;2FyKF(
{ h$`zuz
bStop = true; 05SK$ Y<<
} h[*:\P`
F .hA.E
v=8sj{g3,3
} HAKB@h)
[[FDt[ l4
r&rip^40
/* ?cur}`
**FileAccess.java !a9`]c
*//文件访问(定位，写) 4J5 RtK
package NetFox; ?q{HS&k
import java.io.*; 1buVV]*~
\Dlmrke
1Y+g^Z;G
public class FileAccessI implements Serializable{ A r,fmq
0#y i5U
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 &) qs0
RandomAccessFile oSavedFile; 6Cj$x.-K
long nPos; nF1}?
W#Eg\nT
[%LIW%t|
public FileAccessI() throws IOException 0&Z+P?Wb4
{ a'!p^/6?
this("",0); T"_f9?
} 3q-Xj:FP
BG/Q7s-?K
SPu+t3
public FileAccessI(String sName,long nPos) throws IOException eHE?#r16Z
{ XP%/*am
oSavedFile = new RandomAccessFile(sName,"rw"); (/$a*$
this.nPos = nPos; Bcl6n@{2f
oSavedFile.seek(nPos); ,hSTR)
} :q34KP
WJU[+|J
JavSR1_
public synchronized int write(byte[] b,int nStart,int nLen) N!lQ;o'
{ Wj INY
int n = -1; s:zz8oN
try{ 5}Z_A?gy
oSavedFile.write(b,nStart,nLen); 6<SX%Bc~
n = nLen; 2 Q}^<^r
} '5etZ!:
catch(IOException e) 1fMl8[!JLu
{ D}T+X;u)K
e.printStackTrace (); b|Sjh;
} 3]rd!Gp=*
S;tv4JY
lvp8{]I<
return n; >Q#\X=a>
} zvOSQxGQ
+'V ,z
HDHC9E6
} }cO}H2m
,V &RpKek
\Z8:^ct.P
/* _Gtq]`y
**SiteInfoBean.java UFPSQ
*/ Z/oP?2/Afh
package NetFox; vYNu=vnM
|2!cPf^8
*\#?)q
public class SiteInfoBean { WfH4*e
f#3!Q!C^
m{?uR.O
private String sSiteURL; //Site's URL U2CCjAgRs
private String sFilePath; //Saved File's Path yL#2|t(
private String sFileName; //Saved File's Name kWZ/O
private int nSplitter; //Count of Splited Downloading File i%# <Hi7
dOFK;
M/evZ?uis
public SiteInfoBean() "JpnmE[`
{//nSplitter的缺省值为5 9jf2b
//default value of nSplitter is 5 NR.YeKsBq
this("","","",5); q[5&
} f9a_:]F
><w=
cz;gz4d8
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) T:0#se
{ F.$NYr/|y
sSiteURL= sURL; }%Vx2Q
sFilePath = sPath; RxUzJ
sFileName = sName; Sp\ 7
this.nSplitter = nSpiltter; {GhM,-%e
d: LP8
:<PwG]LO
} [DSD[[ z[
!g7bkA
0oPcZ""X]
public String getSSiteURL() ZUK'z
{ )uazB!X
return sSiteURL; )^]1j$N=3
} Np2.X+
l~'NqmXe
cIOM}/gqv
public void setSSiteURL(String value) Rd:wMy$
{ L@x#:s=
sSiteURL = value; &pN/+,0E
} WmTg`[
fl*>m,
MD,+>kh
public String getSFilePath() n]a/nv
{ w6G<&1iH
return sFilePath; |YWX.-aeo
} ]vUTb9>{?
cwBf((~
J`[He$7)
public void setSFilePath(String value) I3" GGp3L
{ |P`:NAf2
sFilePath = value; dZ{yNh.]
} ,+o*>fD
TW!>~|U)y
%Kc2n9W
public String getSFileName() {i|$^A3
{ b$/'dnx
return sFileName; ST25RJC
} 0k6S`e9gI
>?)Df(n(9
@DniYt/
public void setSFileName(String value) FWl'='5L
{ m8NKuhu
sFileName = value; :uQ~?amM
} MtXTh*4
xyPz_9
C?fa-i0l^
public int getNSplitter() xSL%1>MrN
{ lbnH|;`$]m
return nSplitter; G !;<#|a
} {/K_NSg+h
~[3B<^e
m\;@~o'k
public void setNSplitter(int nCount) vj4n=F,Z
{ WN9K*Tt~o&
nSplitter = nCount; C ]+J
} | x/Z qY
} ylPDM7Ka
THf*<|
\%$z!]S>
/* 6rg?0\A<
**Utility.java KQ2jeJ/pj
*/ \K%A}gnHe
package NetFox; JVt(!%K}&
nWb0S
qgk6 \&K[
public class Utility { %eQw\o,a
`AcT}.u
W=ar&O~}n
public Utility() ;=F]{w]$+
{ VtzX I2.2
4pC.mRu 0
>Z&Y!w'A|u
} *\T ]Z&E"
FCPiU3
//线程睡眠 (|_N2R!
public static void sleep(int nSecond) ' Y cVFi
{ $*z>t*{7
try{ #t?tt,nc}
Thread.sleep(nSecond); j/PNi@
} iw?*Wp25
catch(Exception e) 3lT>C'qq
{ XXA1%Lw%
e.printStackTrace (); cr"AK"TQ
} g1B[RSWv
} '/v@q]!
@WfX{485
//日志 1GI/gc\
public static void log(String sMsg) k.("<)
{ *9I/h~I
System.err.println(sMsg); <{kr5<
} kZJ.G
)ND%MYJSq
g}Esj"7
public static void log(int sMsg) P8=!/L2?
{ r'~^BLT`#
System.err.println(sMsg); ExJexjOWI^
} T~JE.Y3B3
} 1@vlbgLr@
/`vn/X^?^
F3pBk)>a\
/* ">hOD'PG
**TestMethod.java b%"Lwqdr7
*/ TX7]$Wj
package NetFox; M->$'Zgh`
AV:P/M^B
5\\a49k.p
public class TestMethod { R1lC_G]
YNV4'
LH]<+Zren
public TestMethod() iw)^;8q
{ ///xx/weblogic60b2_win.exe }vspjplk^
try{ %jnSJjcq
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); i |IG
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); @$ggPrs
SiteFileFetch fileFetch = new SiteFileFetch(bean); AHl1{* [
fileFetch.start(); LCf)b>C*
} Z[pMlg6Z
catch(Exception e){e.printStackTrace ();} /Xo8 kC
N6wCCXd
]> 36{k]&
} ic]b"ItD
0}d^UGD
>Qg 9KGk'
public static void main(String[] args) W]U},g8Z
{ @Wb_Sz4`
new TestMethod(); 2qkZ B0[
} o2vBY]Tj
} Fy8$'oc
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