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: -LyIu#
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CountBean.java {#vo^& B
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/* -8IiQRS
* CountData.java P1t5-q
* 4:.M*Dz
* Created on 2007年1月1日, 下午4:44
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* &~i1 @\]
* To change this template, choose Tools | Options and locate the template under $Ix^Rm9c
* the Source Creation and Management node. Right-click the template and choose }^H_|;e1p
* Open. You can then make changes to the template in the Source Editor. *b&|
*/ 7%hMf$KQ
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package com.tot.count; 7$ 'ja
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/** >_@J&vC
* FW2} 9#R
* @author }5K\l
*/ {S?.bT%&
public class CountBean { %\A~w3 E
private String countType; H_{Yr+p
int countId; BsJClKp/
/** Creates a new instance of CountData */ uZfo[_g0S
public CountBean() {} j0J6ySlY
public void setCountType(String countTypes){ %n^]1R#
this.countType=countTypes; fIu/*PFPVY
} d/MMPge3
public void setCountId(int countIds){ R7#B_^ $
this.countId=countIds; 7*sB"_U2
} +p2)uXqW
public String getCountType(){ .L}ar7
return countType; WaYT\CG7y
} zQ6otDZx
public int getCountId(){ %NvY~,
return countId; *p"%cas
} %
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} k3&Wv
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CountCache.java [,VD^\
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/* nk[ixVc
* CountCache.java zJPzI{-w|
* \QVL%,.%M
* Created on 2007年1月1日, 下午5:01 T!8,R{V]4
* *cf#:5Nl
* To change this template, choose Tools | Options and locate the template under SO|$X
* the Source Creation and Management node. Right-click the template and choose p?5zwdX+`
* Open. You can then make changes to the template in the Source Editor. "_lSw3
*/ ?Pa5skqR
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package com.tot.count; `U(FdT
import java.util.*; kxh
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/** KcHW>IBxdv
* ]`LMyt0
* @author YM-,L-HMA
*/ -Wf 2m6t
public class CountCache { )<%GHDWL
public static LinkedList list=new LinkedList(); T{Av[>M
/** Creates a new instance of CountCache */ LBTf}T\
public CountCache() {} iNcB6,++
public static void add(CountBean cb){ 06ZyR@.@v
if(cb!=null){ uT_bA0jK
list.add(cb); lwSA!W
} k/>k&^?
} Z<`QDBN"4
} 3qP!
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CountControl.java yN9/'c~
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/* +d<o2n4!
* CountThread.java t\ ym4`"
* s~3"*,3@
* Created on 2007年1月1日, 下午4:57 'bTtdFvJ
* q>t#5Z81
* To change this template, choose Tools | Options and locate the template under b}WU
* the Source Creation and Management node. Right-click the template and choose @u?m4v{
* Open. You can then make changes to the template in the Source Editor. qeypa!
*/ nPE{Gp) }
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package com.tot.count; ta%yQd7
import tot.db.DBUtils; u{J$]%C
import java.sql.*; F8nR.|
/** *y0TtEd;
* &=~Jw5WK
* @author f-^JI*hj
*/ _vm ~yKId
public class CountControl{ p[>!;qI
private static long lastExecuteTime=0;//上次更新时间 }Ge$?ZFH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 RGsgT ^
/** Creates a new instance of CountThread */ a0~LZQ?
public CountControl() {} 3v\}4)A[
public synchronized void executeUpdate(){ 0
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Connection conn=null; ]v=A}}kS
PreparedStatement ps=null; PY[nnoF"|
try{ 0l;TZf=H
conn = DBUtils.getConnection(); P`^nNX]x+,
conn.setAutoCommit(false); kZ$2Uss
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @cukoLAn
for(int i=0;i<CountCache.list.size();i++){ >4
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CountBean cb=(CountBean)CountCache.list.getFirst(); 8u6*;*o
CountCache.list.removeFirst(); G0)}?5L1J
ps.setInt(1, cb.getCountId()); ;0FfP
ps.executeUpdate();⑴ ,N93 H3(
//ps.addBatch();⑵ $i1$nc8
} wNtC5
//int [] counts = ps.executeBatch();⑶ :<hM@>eFn
conn.commit(); ^M0
}catch(Exception e){ ]jjHIFX
e.printStackTrace(); zc K`hS
} finally{ *PM#ngLX}r
try{ }]<0!q &xB
if(ps!=null) { DHQS7%)f`
ps.clearParameters(); xa8;"Y~"bg
ps.close(); VYbH:4K@%
ps=null; ^,}1^?*
} gamE^Ee
}catch(SQLException e){} a`I
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DBUtils.closeConnection(conn); XlLG/N
} a@!(o )>
} o, PpD,,
public long getLast(){ ?.Q$@Ih0
return lastExecuteTime; \(_(pcl
} /*P) C'_M
public void run(){ $O3.ex V
long now = System.currentTimeMillis(); gWQ(B
if ((now - lastExecuteTime) > executeSep) { `3g5n:"g\
//System.out.print("lastExecuteTime:"+lastExecuteTime); }k;wSp[3
//System.out.print(" now:"+now+"\n"); 0RgE~x!hI
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [4w*<({*
lastExecuteTime=now; zG{P5@:.R
executeUpdate(); xqs ,4bcbY
} ox*1F+Xri
else{ .J<t]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0CO@@`~4
} 9HB+4q[
} xpX<iT>5u
} ~y{_NgMo
//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 ;* QK^ #
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类写好了,下面是在JSP中如下调用。 >
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<% 4O<sE@X
CountBean cb=new CountBean(); 4M#i_.`z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); h+=IxF4
CountCache.add(cb); ":0u%E?s
out.print(CountCache.list.size()+"<br>"); 3^[P
CountControl c=new CountControl(); =^1jVaAL
c.run(); EQN)y27poW
out.print(CountCache.list.size()+"<br>"); tk]D)+{u&c
%>