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: (SCZ.G(>
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CountBean.java bo??91B^7
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/* 5>:p'zI
* CountData.java uG/b Cb+V
* KkJE-k*D+w
* Created on 2007年1月1日, 下午4:44 Oiw!d6"Ovq
* Ko!a`I2M}
* To change this template, choose Tools | Options and locate the template under ]E*xn
* the Source Creation and Management node. Right-click the template and choose 6J965eM'[
* Open. You can then make changes to the template in the Source Editor. cef:>>6_
*/ <899r \
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package com.tot.count; SbobXTbG
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/** }5d|y*
* :2lM7|@/
* @author Of
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*/ m:g%5'qDZ
public class CountBean { zR%)@wh
private String countType; 9S?b &]
int countId; ^fU,9
/** Creates a new instance of CountData */ xw*/8.Md6f
public CountBean() {} 0a+U >S#
public void setCountType(String countTypes){ C?rb}(m
this.countType=countTypes; r3YfY\
} QaOFl`i
public void setCountId(int countIds){ kqCUr|M.P
this.countId=countIds; m.U&O=]5
} 5(DnE?}vo
public String getCountType(){ rD>q/,X=\
return countType; /b{Ufo3v
} [5]*
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public int getCountId(){ Ct0%3]<J
return countId; G)=+Nt\*
} NV^n}]ci
} ?o d*"M
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CountCache.java 5?TjuGc
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/* v8THJf
* CountCache.java UmCIjwk
* 6 w0r)
* Created on 2007年1月1日, 下午5:01 ~gEd(
* {z# W-
* To change this template, choose Tools | Options and locate the template under PR>%@-Vgj
* the Source Creation and Management node. Right-click the template and choose mTa^At"
* Open. You can then make changes to the template in the Source Editor. P1ynCe
*/ w.Kp[
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package com.tot.count; ZQ~EaI9R
import java.util.*; =YR+`[bfI
/** Wp=:|J
* jE$]Z(Ab
* @author =l$qwcfbo
*/ (<yQA. M
public class CountCache { o &E2ds3
public static LinkedList list=new LinkedList(); <-|g>
/** Creates a new instance of CountCache */ j2:A@a6
public CountCache() {} i^/D_L.
public static void add(CountBean cb){ zQx7qx
if(cb!=null){ WtbOm
list.add(cb); g@S?5S.Av
} cs)z!
} p B79#4
} oSoU9_W
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CountControl.java I=V]_Ik4N
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/* W.<I:q`eO
* CountThread.java J]Qbg7|
* [M:BJ%*
* Created on 2007年1月1日, 下午4:57 !%YV0O0
* :;Wh!8+j
* To change this template, choose Tools | Options and locate the template under "cX*GTNi8
* the Source Creation and Management node. Right-click the template and choose V,
e
* Open. You can then make changes to the template in the Source Editor. p:qj.ukw
*/ j=w`%nh4"f
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package com.tot.count; QLyBP!X-
import tot.db.DBUtils; PF-"^2&_
import java.sql.*; ON$-g_s>)
/** Z65]|
* O0>^?dsL
* @author _ 6'HBE
*/ _qhYG1t
public class CountControl{ CFx$r_!~
private static long lastExecuteTime=0;//上次更新时间 4K$d%
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 w24@KaKFo
/** Creates a new instance of CountThread */ lmr:PX
public CountControl() {} (~n0,$
public synchronized void executeUpdate(){ iLG~_Ob:
Connection conn=null; 0t}&32lL&
PreparedStatement ps=null; Amvl/bO
try{ KfLp cV
conn = DBUtils.getConnection(); WUqfY?5
conn.setAutoCommit(false); )WazbT@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); XDq*nA8#5B
for(int i=0;i<CountCache.list.size();i++){ l050n9#9p
CountBean cb=(CountBean)CountCache.list.getFirst(); xn4-^2
CountCache.list.removeFirst(); hlTM<E
ps.setInt(1, cb.getCountId()); b$'}IWNV
ps.executeUpdate();⑴ a(`@u&]WZ
//ps.addBatch();⑵ J;7O`5J
} mGqT_
//int [] counts = ps.executeBatch();⑶ fRd^@@,[
conn.commit(); v/WvT!6V`
}catch(Exception e){ Gd%E337d
e.printStackTrace(); ~!W{C_*N
} finally{ _8"%nV
try{ AIFI@#3
if(ps!=null) { 6'qC *r
ps.clearParameters(); B@2VI
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ps.close(); >~k"C,6
ps=null; Kdwt^8Umh
} X
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}catch(SQLException e){} 2N:|B O>
DBUtils.closeConnection(conn); cp>1b8l6?
} Q'S"$^~{
} k\a&4v
public long getLast(){ r+%}XS%;h
return lastExecuteTime; X,8]g.<
} :;]iUjiC8
public void run(){ lZ9rB^!
long now = System.currentTimeMillis(); P>3
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if ((now - lastExecuteTime) > executeSep) { G\ht)7SGgf
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~1v5H]T{
//System.out.print(" now:"+now+"\n"); K=82fF(-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +1%7*2q,
lastExecuteTime=now; Cl5l+I\1
executeUpdate(); &I$MV5)u
} ("B[P/
else{ 3ud_d>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Wc+)EX~KS
} $kef_*BQg
} kKqb:
} Vyqj)1Z8>
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 P6ztP$M(
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类写好了,下面是在JSP中如下调用。 hf~'EdU
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<% o1kY|cnGH
CountBean cb=new CountBean(); i7/I8y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 09S LQVo
CountCache.add(cb); ``Wf%~
out.print(CountCache.list.size()+"<br>"); |8m;}&r$
CountControl c=new CountControl(); s8/y|HN^
c.run(); ;NHZD
out.print(CountCache.list.size()+"<br>"); !w8t`Z['
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