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: irvd>^&jDC
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CountBean.java 6QJ.=.>b
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/* sAPQbTSM
* CountData.java [qxU
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* Vf.*!`UH
* Created on 2007年1月1日, 下午4:44 Bp@\p)P(
* s: iBl/N}
* To change this template, choose Tools | Options and locate the template under R4T@ ]l&W
* the Source Creation and Management node. Right-click the template and choose +FAxqCkA
* Open. You can then make changes to the template in the Source Editor. 8B]\;m
*/ 2(x|
%
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package com.tot.count; 4q:8<*W=
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#
/** Om;aE1sW
* _n!>*A!
* @author N=7iQ@{1
*/ uMpuS1
public class CountBean { _ker,;{9C
private String countType; q@~{g[
int countId; wjZ Q.T!
/** Creates a new instance of CountData */ GmE`YW
public CountBean() {} s$,G5Feub
public void setCountType(String countTypes){ 9+$IulOvk
this.countType=countTypes; HG< z,gE
2
} VbMud]40F
public void setCountId(int countIds){ isdNW l
this.countId=countIds; Q+wO\TtE
} b:r8r}49
public String getCountType(){ Xit@.:a;
return countType; fI2y(p{?
} S8+l!$7
public int getCountId(){ \jV2":[%c
return countId; DU)q]'[u
} k3e6y
} &<_q00F
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CountCache.java N`$F>E,T%
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/* 6J#R1.h
* CountCache.java wq,&0P-v
* .qKfhHJ
* Created on 2007年1月1日, 下午5:01 :8`$BbV
* R,["w98a
* To change this template, choose Tools | Options and locate the template under TQ:e!
32
* the Source Creation and Management node. Right-click the template and choose I Z*)
* Open. You can then make changes to the template in the Source Editor. $T:;KcW)
*/
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package com.tot.count; ?u;m
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import java.util.*; _Ve)M%
/** $)c[FR~a
* BNA1"@9q
* @author 4p+Veo6B
*/ "PWGtM:L8Y
public class CountCache { ZR0 OqSp]
public static LinkedList list=new LinkedList(); Rq e|7/As
/** Creates a new instance of CountCache */ @%*@Rar
public CountCache() {} n%RaEL
public static void add(CountBean cb){ u|.|dv'mbp
if(cb!=null){ :xq{\"r
list.add(cb); "VHT5k
} ~`^kP.()
} BB9eQ:
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} =sv?))b`
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CountControl.java 2M\7j
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/* #O,w{S
* CountThread.java )c1Pj#|
* 5D?{dA:Rq
* Created on 2007年1月1日, 下午4:57 $I/ !vV
* CS*lk!C
* To change this template, choose Tools | Options and locate the template under d8R|0RZ
* the Source Creation and Management node. Right-click the template and choose d(d3@b4Ta
* Open. You can then make changes to the template in the Source Editor. m@*aA}69
*/ \I/"W#\SJo
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package com.tot.count; VKu_l
import tot.db.DBUtils; pFiE2V_aS
import java.sql.*; lA4J#
/** Mh3L(z]/E
* w8cnSO
* @author N>sT@ >
)
*/ "Wk K1u
public class CountControl{ 8'fF{C
private static long lastExecuteTime=0;//上次更新时间 RtxAIMzh?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ PR(KDwsT&l
public CountControl() {} [I'q"yRu]i
public synchronized void executeUpdate(){ 1|G5 W:
Connection conn=null; p14$XV
PreparedStatement ps=null; k%-UW%
try{ ?$<~cD" Sw
conn = DBUtils.getConnection(); CI \O)iB
conn.setAutoCommit(false); Bd;EI)JT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $:-C9N29
for(int i=0;i<CountCache.list.size();i++){ ,,IK}
CountBean cb=(CountBean)CountCache.list.getFirst(); RLLL=?W@
CountCache.list.removeFirst(); 6 !fq658
ps.setInt(1, cb.getCountId()); )[&j&AI
ps.executeUpdate();⑴ /Jc^XWf
//ps.addBatch();⑵ [!} uj`e
} 8F)9.s,*
//int [] counts = ps.executeBatch();⑶ ntL%&wY
conn.commit(); ww%4MHPp8
}catch(Exception e){ _x`:Ne?
e.printStackTrace(); yd45y}uS;F
} finally{ _jxysFl=
try{ ,s@S`KS0
if(ps!=null) { Tn38]UL
ps.clearParameters(); 8jLO-^X<<
ps.close(); NB( GE
ps=null; ?iaO6HD
} :
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}catch(SQLException e){} "68=dC
DBUtils.closeConnection(conn); RcI0n"Gi_
} w%6 L"
} IY2f$YV
public long getLast(){ (51;cj>J
return lastExecuteTime; gJ$m'kC;
} x_4{MD^%
public void run(){ ty9(mtH+
long now = System.currentTimeMillis(); L'>0E(D
if ((now - lastExecuteTime) > executeSep) { -#AO4xpI
//System.out.print("lastExecuteTime:"+lastExecuteTime); o 7 &q
//System.out.print(" now:"+now+"\n"); R_:-Z.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4&`d$K
lastExecuteTime=now; S8]YS@@D
executeUpdate(); `M_w^&6+n
} &v+Hl^
else{ 9v}vCg
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); f{D~ZC.*
} v(jZ[{x@
} %Vsg4DRy
} SR9M:%dga
//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 8RVeKnpXTV
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类写好了,下面是在JSP中如下调用。 U }}E
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<% '494^1"io
CountBean cb=new CountBean(); qNbgN{4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); hB]<li)"C
CountCache.add(cb); uF-Rl##
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out.print(CountCache.list.size()+"<br>"); LO,k'gg<
CountControl c=new CountControl(); 0av2w5>af
c.run(); NUX2{8gs
out.print(CountCache.list.size()+"<br>"); BUEV+SZ4
%>