有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: .s*N1
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CountBean.java xj>P5\mW#
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/* KQNQ<OE4
* CountData.java *O~y6|U?
* 4@{cK|
* Created on 2007年1月1日, 下午4:44 d/Q#Z
* t2(X
* To change this template, choose Tools | Options and locate the template under .))jR:{3
* the Source Creation and Management node. Right-click the template and choose 3&^hf^yg
* Open. You can then make changes to the template in the Source Editor. vY m:V:7Y2
*/ "@eGgQ
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package com.tot.count; Q/4-7
@c]KHWI
/** Gg'!(]v
* .T9$O]:o
* @author m1pA]}Y/5o
*/ A,<5W }
public class CountBean { {wz)^A
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private String countType; 0>BxS9?w
int countId; y2_rm
/** Creates a new instance of CountData */ @^UgdD,BS,
public CountBean() {} IAH"vHM
public void setCountType(String countTypes){ }S uj=oFp
this.countType=countTypes; MrHJ)x"hy
} Pl:4`oY3
public void setCountId(int countIds){ %@Gy<t,
this.countId=countIds; \s*UUODWK
} B.r^'>jQ
public String getCountType(){ spfW)v/T!
return countType; dXh[Ea^
} vYV!8o.I
public int getCountId(){ BrE#.g Jq
return countId; 6v3l^~kc'
} @@oJ@;
} ?0/$RpFEM#
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CountCache.java $UH:r
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/* i|1*bZ6'
* CountCache.java >SDQ@63E?
* (Ut8pa+yX
* Created on 2007年1月1日, 下午5:01 ;Yee0O!d4
* !y b06Z\f
* To change this template, choose Tools | Options and locate the template under B8Fb$
* the Source Creation and Management node. Right-click the template and choose aG
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* Open. You can then make changes to the template in the Source Editor. /(JG\Ut
*/ e&z@yy$
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package com.tot.count; 2X\Pw
import java.util.*; -H6[{WVW!
/** BwWSztJ+B
* MTtx|L\4
* @author )%@7tx
*/ %JE>Z]
public class CountCache { 4}m9,
public static LinkedList list=new LinkedList(); N4+Cg t(
/** Creates a new instance of CountCache */ IrL%0&*hS
public CountCache() {} 2V)+ba|+
public static void add(CountBean cb){ g9" wX?*
if(cb!=null){ F9o7=5WAb
list.add(cb); Xb%Q%"?~
} vWoppt
} !ddyJJ^a
} Q[#}Oh6$
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CountControl.java ({j8|{)+
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/* dHIk3j-!
* CountThread.java S3Y.+. 0U
* GmR3
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* Created on 2007年1月1日, 下午4:57 nnj<k5
* H7tviSTd
* To change this template, choose Tools | Options and locate the template under (U&
* the Source Creation and Management node. Right-click the template and choose -SM_JR3<
* Open. You can then make changes to the template in the Source Editor. $$m0mK
*/ i6KfH\{N
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package com.tot.count; N 5*Qnb8
import tot.db.DBUtils; 4tCM2it%
import java.sql.*; a|z-EKV
/** v]( Y n)#
* |qMG@
* @author FJZ'P;3
*/ *Mhirz%iD
public class CountControl{ ~".@mubt1$
private static long lastExecuteTime=0;//上次更新时间 g{DehBM
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 LXo$\~M8G8
/** Creates a new instance of CountThread */ s0' haU
public CountControl() {} 32 i6j
public synchronized void executeUpdate(){ 7{}E{/
Connection conn=null; C^"zU>W_
PreparedStatement ps=null; eY :"\c3
try{ rByth,|
conn = DBUtils.getConnection(); vIJ5iLF
conn.setAutoCommit(false); N-upNuv
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [<53_2]~
for(int i=0;i<CountCache.list.size();i++){ >Y08/OAI.2
CountBean cb=(CountBean)CountCache.list.getFirst(); j_2g*lQ7a
CountCache.list.removeFirst(); V#w$|2
ps.setInt(1, cb.getCountId()); _+By=B.'
ps.executeUpdate();⑴ P#hRqETw
//ps.addBatch();⑵ \eKXsO"d
} 1 .+O2qB
//int [] counts = ps.executeBatch();⑶ >}* W$i
conn.commit(); :o8`2Z *g
}catch(Exception e){ nz?[
e.printStackTrace(); UAF$bR
} finally{ #S?^?3d
try{ ;F258/J
if(ps!=null) { "BSY1?k{
ps.clearParameters(); #<)[{+f[t
ps.close(); /GGyM]k3
ps=null; UH>~Y
N
} 72Bc0Wg
}catch(SQLException e){} "?zWCH
DBUtils.closeConnection(conn); zj r($?
} eV*QUjS~
} rtS cQ
public long getLast(){ ,<L4tp+y0
return lastExecuteTime; r[!~~yu/o
} )58O9b
public void run(){ 06&;GW!-
long now = System.currentTimeMillis(); \]<R`YMV
if ((now - lastExecuteTime) > executeSep) { `e,}7zGR
//System.out.print("lastExecuteTime:"+lastExecuteTime); m
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//System.out.print(" now:"+now+"\n"); dnLjcHFj&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 90}vFoy
lastExecuteTime=now; }oZ8esZU2
executeUpdate(); AF#:*<Ev
} ysOf=~1
else{ ZFtR#r(~41
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4N,[Gs<7
} *Vl#]81~
} Ij(<(y{?Q1
} 1TTS@\
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 +1T>Ob;hk
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类写好了,下面是在JSP中如下调用。 LKvX~68
@LI;q
<% 6c]4(%8
CountBean cb=new CountBean(); @;eH~3P
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); h/tCve3Z
CountCache.add(cb); G06;x
out.print(CountCache.list.size()+"<br>"); nqH[
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CountControl c=new CountControl(); ]z'L1vQl7
c.run(); \L(jNN0_R
out.print(CountCache.list.size()+"<br>"); bWA_a]G
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