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)); lBOxB/`
} eu?DSad
for(int i=0;i<nEndPos.length-1;i++) s"0Hz"[^=
{ r?=3TAA
nEndPos = nStartPos[i+1]; nbU?:=P
} biAa&
nEndPos[nEndPos.length-1] = nFileLength; 8,?*eYNjb
} QQX7p!~E
} {3\{aZ8)
XM?C7/^k
3qrjb]E%}
//启动子线程 a*Ng+~5)6
fileSplitterFetch = new FileSplitterFetch[nStartPos.length]; p/Lk'h~
for(int i=0;i<nStartPos.length;i++) *!yY7 ~#
{ ^a;412
fileSplitterFetch = new FileSplitterFetch(siteInfoBean.getSSiteURL(), :X#'ELo|
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), vN`JP`IBx
nStartPos,nEndPos,i); $Q*^c"&
Utility.log("Thread " + i + " , nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); +ZPn[|
fileSplitterFetch.start(); >SHW
} =_,j89E
// fileSplitterFetch[nPos.length-1] = new FileSplitterFetch(siteInfoBean.getSSiteURL(), E3h-?ugO'
siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(),nPos[nPos.length-1],nFileLength,nPos.length-1); 3 bll9Ey
// Utility.log("Thread " + (nPos.length-1) + " , nStartPos = " + nPos[nPos.length-1] + ", xU$15|ny
nEndPos = " + nFileLength); "$N 4S9U
// fileSplitterFetch[nPos.length-1].start(); ug9]^p/)^
JS0957K
.Wvg{ S-
//等待子线程结束 !v]~ut !p
//int count = 0; f5hf<R),A
//是否结束while循环 *^.OqbO[U
boolean breakWhile = false; fZrB!\Q
5Q@4@b{C
Ia*T*qJu
while(!bStop) -v?)E S
{ ^uWj#
write_nPos(); n.xOu`gj
Utility.sleep(500); t$b{zv9C
breakWhile = true; OT}^dPQe
+&8'@v$
1Et{lrgh f
for(int i=0;i<nStartPos.length;i++) Xa/]} B
{ \$D41_Wt|
if(!fileSplitterFetch.bDownOver) S+//g+e|f
{ #l-/!j
breakWhile = false; ? ]hS^&
break; (/3E,6gMk^
} 6yXMre)YV
} Mg=R**s1x%
if(breakWhile) GQ=Pkko
break; 8Z(\iZ5Rgj
EY'48S
5tm:|.`SQ
//count++; t-$Hti7Lk
//if(count>4) lhduK4u
// siteStop(); qre(3,VE5
} IyGW>g6_.
khfWU
oD~q/04!
System.err.println("文件下载结束！"); =FXq=x%9+
} t{Gc,S!]5
catch(Exception e){e.printStackTrace ();} \xexl1_;
} _f<#+*y
55vI^SSA
-3&mgd
//获得文件长度 +{"w5o<CO
public long getFileSize() ]`_eaW?Ua
{ RWINdJZ
int nFileLength = -1; 0;x<0P
try{ 5Z(#)sa0Og
URL url = new URL(siteInfoBean.getSSiteURL()); L QA6iZBP
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); AWz|HF#-
httpConnection.setRequestProperty("User-Agent","NetFox"); yVbyw(gS
38gEto#q
nSeb?|$D6
int responseCode=httpConnection.getResponseCode(); tz`T#9
if(responseCode>=400) F`JW&r\
{ qJT|om LY
processErrorCode(responseCode); -)Y[t Z^*`
return -2; //-2 represent access is error Dh B*k<S
} H(F9&6}
]5j1p6;(`
}X^CH2,R
String sHeader; O(YvE
s!\Gi5b
R)BH:wg"
for(int i=1;;i++) -{s9PZ3~_
{ XT~]pOE;D
//DataInputStream in = new DataInputStream(httpConnection.getInputStream ()); ~mYCXfoc{
//Utility.log(in.readLine()); {.D/MdwW;
sHeader=httpConnection.getHeaderFieldKey(i); f&L8<ASFo
if(sHeader!=null) ^?o>(K
{ +}.S:w_xQ
if(sHeader.equals("Content-Length")) [p&2k&.XYe
{ PBp+(o-
nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader)); QN OA66
break; \4roM1&[
} u^]Z{K_B
} !:9s>0';N
else Q[UYNQ0w
break; 8PwPI%Pb
} 2)47$eu
} o&U/e\zy
catch(IOException e){e.printStackTrace ();} $JZ}=\n7
catch(Exception e){e.printStackTrace ();} !t+eJj
RL~]mI!U
6SN$El 0|G
Utility.log(nFileLength); x] j&Knli
LCkaSv/[RB
\s">trXwX
return nFileLength; W#lt_2!j
} Wc!.{2
rEG!A87Zz
EawtT
//保存下载信息（文件指针位置） PHQ99&F1
private void write_nPos() pm k;5 d
{ 37nGFH`K2m
try{ \K(QE ~y'W
output = new DataOutputStream(new FileOutputStream(tmpFile)); |FxTP&8~
output.writeInt(nStartPos.length); bd@1j`i
for(int i=0;i<nStartPos.length;i++) HC/?o0
{ s.9_/cFWB
// output.writeLong(nPos); $qyST
output.writeLong(fileSplitterFetch.nStartPos); f,QBj{M,
output.writeLong(fileSplitterFetch.nEndPos); H=(Zx
} 40R7@Vaf
output.close(); FG6mh,C!
} ipn0WQG
catch(IOException e){e.printStackTrace ();} #x[3@zP.
catch(Exception e){e.printStackTrace ();} h$rk]UM/Q
} w@&(=C
AG(Gtvw
i+eDBg6
//读取保存的下载信息（文件指针位置） 4'BZ+A,p
private void read_nPos() pQ yH`
{ "?#O*x
try{ Q9NKQuSu
DataInputStream input = new DataInputStream(new FileInputStream(tmpFile)); -VhxnhS
int nCount = input.readInt(); Y<9]7R(\;
nStartPos = new long[nCount]; UZb!tO2
nEndPos = new long[nCount]; d0 qc%.s
for(int i=0;i<nStartPos.length;i++) ^A' Bghy
{ ;J&9l >
nStartPos = input.readLong(); <A@qN95m
nEndPos = input.readLong(); .YxcXe3#
} a5@XD_b
input.close(); U((mOm6
} I2^Eo5'
catch(IOException e){e.printStackTrace ();} @bO/5"X,
catch(Exception e){e.printStackTrace ();} Y!w {,\3
} fi;00>y
Tg\wBhJr|
%:/?eZ
private void processErrorCode(int nErrorCode) 1@{qPmf^
{ J!@`tR-
System.err.println("Error Code : " + nErrorCode); :zLeS-
} W:* {7qJ
U<jAZU[L
QTT2P(Pz
//停止文件下载 GBo'=
public void siteStop() A~%h*nZc%I
{ +w'He9n
bStop = true; %m?$"<q_K
for(int i=0;i<nStartPos.length;i++) ]iE)8X
fileSplitterFetch.splitterStop(); *#g[ jl4
Ft^+P*
\:|"qk
} @w{"6xc%a
} &JHqUVs^
//负责部分文件的抓取 ypV>*
**FileSplitterFetch.java '7(oCab"_
*/ *nc9u"
package NetFox; $KMxq=
6h3TU,$r
fs;pX/:FR
import java.io.*; 4NxI:d$&*
import java.net.*; ePxwN?
.}x:yKyi@
9 Z79
public class FileSplitterFetch extends Thread { do&0m[x%
c3q @]|aI
[2Ot=t6]
String sURL; //File URL D;QV`Z%I
long nStartPos; //File Snippet Start Position v!77dj 6I
long nEndPos; //File Snippet End Position M&~cU{9c
int nThreadID; //Thread's ID n+%tu"e
boolean bDownOver = false; //Downing is over <Pg<F[eDM
boolean bStop = false; //Stop identical Kb,#Ot
FileAccessI fileAccessI = null; //File Access interface (Q~(t
6*tbil_G+
&=`6- J
public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException z)0%gd|
{ $mLiEsJ
this.sURL = sURL; v7@O ,%
this.nStartPos = nStart; @1^:V-=
this.nEndPos = nEnd; E!zAUEVQm[
nThreadID = id; T,SCK^
fileAccessI = new FileAccessI(sName,nStartPos);//定位 PuoN<9 #
} ZKco
?Y|*EH
C:$pAE(
public void run() TB(!*t
{ VaLl$w
while(nStartPos < nEndPos && !bStop) f%cbBx^;
{ IM9P5?kJ ?
9i*Xd$ G
i8H!4l
try{ =V*4&OU
URL url = new URL(sURL); R'1L%srTM+
HttpURLConnection httpConnection = (HttpURLConnection)url.openConnection (); 5KvqZ1L
httpConnection.setRequestProperty("User-Agent","NetFox"); 2z615?2_U
String sProperty = "bytes="+nStartPos+"-"; #uillSV
httpConnection.setRequestProperty("RANGE",sProperty); DY6ra% T
Utility.log(sProperty); (D <o=Q
fS?fNtD6<
Od@<L
InputStream input = httpConnection.getInputStream(); &j_:VP
//logResponseHead(httpConnection); #7yy7Y5
AagWswv{Bf
("-`Y'"K
byte[] b = new byte[1024]; nps"nggk
int nRead; 5X=ik7m^
while((nRead=input.read(b,0,1024)) > 0 && nStartPos < nEndPos && !bStop) @#W$7Gwf0
{ k>mqKzT0$+
nStartPos += fileAccessI.write(b,0,nRead); CKgbb4;<m[
//if(nThreadID == 1) -|x YT+?%
// Utility.log("nStartPos = " + nStartPos + ", nEndPos = " + nEndPos); OJ2I (8P
} bJ6@ B<
bhg OLh#
Xsit4Ma
Utility.log("Thread " + nThreadID + " is over!"); 4[^lE?+
bDownOver = true; >W7IWhm3
//nPos = fileAccessI.write (b,0,nRead); Wk*t-
} "Ir.1FN
catch(Exception e){e.printStackTrace ();} Mh;rhQ
} g1zX^^nd,V
} "}'Sk(
Q]NGd 0J
^tY$pPA
//打印回应的头信息 96.Vm*/7
public void logResponseHead(HttpURLConnection con) 5*31nMP\
{ cAAyyc"yJ
for(int i=1;;i++) wc6v:,&
{ Pu7cL
String header=con.getHeaderFieldKey(i); At=l>
if(header!=null) 2W]y9)<c
//responseHeaders.put(header,httpConnection.getHeaderField(header)); qtLXdSc
Utility.log(header+" : "+con.getHeaderField(header)); jYi{[**
else iJD_qhd7
break; 6*r3T:u3
} `.8#q^
} k9iXVYQ.;r
baL-~`(T
e+=IGYC
public void splitterStop() "=r"c$xou
{ -yn;Jo2-
bStop = true; Up|>)WFw"
} | *J-9
#v QyECf
,H+LE$=
} &}/h[v_#'
oy!Dm4F
%/(>>*}Kw|
/* \r+8}8
**FileAccess.java G oJ\6&"
*//文件访问(定位，写) bu|ecv
package NetFox; sBfPhBT|
import java.io.*; en6oFPG
L4,Ke
b 7%O[
public class FileAccessI implements Serializable{ <DjFMTCN
"TgE@bC
//RandomAccessFile类用于在任意一个文件的特定位置上读/写字节 rJ UXA<:2
RandomAccessFile oSavedFile; ]A2l%V_7
long nPos; V*U*_Y
:*wjC.Z
u/2!v(
public FileAccessI() throws IOException s*0PJ\E2
{ }|7y.*
this("",0); i`2X[kc
} l[J'FR:
z nc'
T)NnWEB
public FileAccessI(String sName,long nPos) throws IOException &@MiR8
{ c#6g[TE@
oSavedFile = new RandomAccessFile(sName,"rw"); *1[v08?!
this.nPos = nPos; `/z6Q"
oSavedFile.seek(nPos); <_tkd3t#W
} 7~V,=WEe
dq{wFI)
AqzPwO^
public synchronized int write(byte[] b,int nStart,int nLen) }`,}e259
{ '~ {xn
int n = -1; < <vE.
try{ lV0\UySH
oSavedFile.write(b,nStart,nLen); NHCdf*
n = nLen; -OS&(7
} u0(PWCi2
catch(IOException e) d* 6 lJT
{ lbtVQW0V;o
e.printStackTrace (); krC4O2Fkj
} ?5<Q+G0r
UA|A>c
x1}7c9nK
return n; u0@i3Po
} ZE*m;
(IXe555
Q/,bEDc&
} =k1 ,jn+
d,G:+
vNhi5EU
/* <?UIux
**SiteInfoBean.java KnC;j-j
*/ /@<Pn&Rq
package NetFox; z3 lZ3
L]goHs
Qw ukhD7
public class SiteInfoBean { &O'6va
gqje]Zc<
lKMOsr@l
private String sSiteURL; //Site's URL ;:a>#{N
private String sFilePath; //Saved File's Path @k!J}O K
private String sFileName; //Saved File's Name oT4A|M
private int nSplitter; //Count of Splited Downloading File fq.ui3lP)
4X@ <PX5
0z2A!ap
public SiteInfoBean() <J`",h
{//nSplitter的缺省值为5 3+_ .I{
//default value of nSplitter is 5 d_j% ,1-#
this("","","",5); /-qSYS(
} :[1^IH(sb
)5}=^aqd
Nd.+Rs
public SiteInfoBean(String sURL,String sPath,String sName,int nSpiltter) gJ_{V;R
{ -Cjc~{B>7X
sSiteURL= sURL; 2Qqk?;^1
sFilePath = sPath; }hralef #N
sFileName = sName; UvSvgDMl
this.nSplitter = nSpiltter; )")_aA
>xU$)uE&
)x/Spb
} UJXRL
p9;Oe,Il
}dl[~iKW
public String getSSiteURL() |D %m>M6
{ +0016UgS#
return sSiteURL; NW'rqgG
} Q2c|sK8
W)dQyZ>J
ad "yo=%1
public void setSSiteURL(String value) )Jx+R;Z
{ )T1U!n?^x
sSiteURL = value; 8,Jjv*
} Une,Y4{u
gBzg'Z
o~#cpU4{o
public String getSFilePath() sw.cw}1
{ b]'Uv8fbF
return sFilePath; *{qW7x.6h
} TBN0uk
hjVct r
GJ:65)KU
public void setSFilePath(String value) @5!Mr5;
{ y9cDPwi:b
sFilePath = value; }fps~R
} CbmT aEaP
/DG+8u
?v4-<ewD
public String getSFileName() ~s@PP'!
{ -a``
return sFileName; eSNwAExm
} }Ut*Y*
Lo^0VD!O
|H`}w2U[j
public void setSFileName(String value) "|?zQ?E
{ cFcn61x-
sFileName = value; rBd}u+:*
} 5OUGln5
"~R,%sYb(
f}JiYZ
public int getNSplitter() h0}=C_.^
{ D#ZzhHHP
return nSplitter; ;GW[Yw>Rz
} i6L>,^Dg
`nAR/Ye
;JM%O8
public void setNSplitter(int nCount) q\2q3}n
{ RRW/.y
nSplitter = nCount; 'R&Y pR
} X]^FHYjhS
} BI\ )vr$
]JQ7x[
{BkTJQ)
/* $#3O:aW
**Utility.java {}r#s>
*/ v6Vieo=
package NetFox; J!O{.v
]ow$VF{y
dNH6%1(s]0
public class Utility { VRuY8<E
bC_qoI<
K(&I8vAp
public Utility() KIY/nu
{ tPv3nh
dQX<X}
97/"5i9
} =:)p\{B
}HO3D.HE^
//线程睡眠 ,8~qnLy9
public static void sleep(int nSecond) 'Z(KE2&?
{ ?T]` X
try{ 6n[O8^
Thread.sleep(nSecond); EW$.,%b1
} ,"MRA
catch(Exception e) |;~kHc$W
{ <SK%W=
e.printStackTrace (); O*;$))<wX
} ZDMv8BP7
} Ri[ v(Zf
'o D31\@I
//日志 up(6/-/.7
public static void log(String sMsg) 7Cx*Ts$
{ DGR[2C)@N
System.err.println(sMsg); 8>U{>]WG
} g+g0iS
D8Ntzsr6
c[p>*FnP
public static void log(int sMsg) =t[hsl
{ nK95v}p}Y
System.err.println(sMsg); Gi=sJV
} Ue:LKK1Gsr
} vBFMne1h
y {&"g
/wt!c?wR
/* vy:-a G
**TestMethod.java GSHJ?}U,
*/ %pikt7,Z~
package NetFox; (8JL/S;Z$
Lek!5Ug
7D5[ L
public class TestMethod { 2O|jVGap5x
f*Z8C9)
OTgctw1s
public TestMethod() cSbyVC[r
{ ///xx/weblogic60b2_win.exe HPGIz!o
try{ y7f,]<%e_
SiteInfoBean bean = new SiteInfoBean("http://localhost/xx/weblogic60b2_win.exe","L:\\temp","weblogic60b2_win.exe",5); c(@(j8@S
//SiteInfoBean bean = new SiteInfoBean("http://localhost:8080/down.zip","L:\\temp","weblogic60b2_win.exe",5); s5`CV$bz
SiteFileFetch fileFetch = new SiteFileFetch(bean); &c?q#-^)\+
fileFetch.start(); a ~
} !?AgAsSmc
catch(Exception e){e.printStackTrace ();} U?@ s`.
FfeX;pi
6_G[&
} yj:<3_-C*
/$z(BX/
/nPNHO>U
public static void main(String[] args) xbVvK+
{ 8fI]QW
new TestMethod(); L<7KmN4VX
} -0I]Sm;$
} Rcn6puZt
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