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: f{} zqCK
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CountBean.java Aqc
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/* hkK+BmMj\
* CountData.java xK8n~.T('
* n$jOk
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* Created on 2007年1月1日, 下午4:44 MS_@
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* mKsTA;
* To change this template, choose Tools | Options and locate the template under F5*NK!U
* the Source Creation and Management node. Right-click the template and choose F"#8`Ps>
* Open. You can then make changes to the template in the Source Editor. efK3{
*/ C(ay7
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package com.tot.count; T)!$-qdz/
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/** YY&3M
* 3@d{C^\
* @author !I7bxDzK$
*/ +PCsp'D
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public class CountBean { Usa
private String countType; eHjna\ C
int countId; 't3@dz_dG
/** Creates a new instance of CountData */ 0v~Eu>Rg
public CountBean() {} '1$#onx
public void setCountType(String countTypes){ n@hf{hA[a
this.countType=countTypes; Fj0a+r,h!
} `]+-z+
public void setCountId(int countIds){ H1FD|Q3
this.countId=countIds; r35'U#VMk?
} ~miRnW*x
public String getCountType(){ o(2tRDT\_b
return countType; FXAP]iqo
} 7]i=eD8
public int getCountId(){ X_j=u1*5
return countId; j:JM v
} vlHE\%{
} 4f}:)M$5
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CountCache.java *=6,}rX"I
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/* A3\%t@y
* CountCache.java fP6]zy^*
* &oA p[]
* Created on 2007年1月1日, 下午5:01 __FhuP P
* ;}=4z^^5
* To change this template, choose Tools | Options and locate the template under !Q`vOVSUD
* the Source Creation and Management node. Right-click the template and choose z_Nw%V4kr
* Open. You can then make changes to the template in the Source Editor. 3#IU^6l:1S
*/ ^kS44pr\Q
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package com.tot.count; yf2I%\p}
import java.util.*; d1MVhE
/** *jBn
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* R^fk :3
* @author AADvk_R
*/ :4{;^|RgU
public class CountCache { Uf:G,%OYi
public static LinkedList list=new LinkedList(); ^G(/;c*=
/** Creates a new instance of CountCache */ 97$1na3gq
public CountCache() {} #WOb&h
public static void add(CountBean cb){ a^9-9*
if(cb!=null){ A?
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list.add(cb); !k=>Wb8n2
} $U uSrX&
} Ik9 2='Z
} dIOj]5H3F
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CountControl.java LPg1 G+e
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/* m&'z|eN
* CountThread.java ^'g1? F$_
* QQd%V#M?
* Created on 2007年1月1日, 下午4:57 12NV
* ~)RKpRga\p
* To change this template, choose Tools | Options and locate the template under 4_#yl9+
* the Source Creation and Management node. Right-click the template and choose " <GDOL
* Open. You can then make changes to the template in the Source Editor. +O@v|}9"w3
*/ x8]9Xe:_>O
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package com.tot.count; STC'j1U
import tot.db.DBUtils; F-^#EkEGe
import java.sql.*; ,W'?F9Y\
/** {kLL&`ii
* WsA(8Ck<
* @author ^:b%QO
*/ %cDTy]ILu
public class CountControl{ )N) "O? W9
private static long lastExecuteTime=0;//上次更新时间 c'9-SY1'~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 HMUn+kk+
/** Creates a new instance of CountThread */ .js@F/Hp
public CountControl() {} Jy,Dcl
public synchronized void executeUpdate(){ nly`\0C
Connection conn=null; R+c
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PreparedStatement ps=null; 6j]pJ]F6
try{ W^c> (d</
conn = DBUtils.getConnection(); >5i(U_`l
conn.setAutoCommit(false); zUw9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =xs{Ov=
for(int i=0;i<CountCache.list.size();i++){ +OUYQM mM
CountBean cb=(CountBean)CountCache.list.getFirst(); (5l5@MN
CountCache.list.removeFirst(); 0FDfB;
ps.setInt(1, cb.getCountId()); a\wpJ|3{=T
ps.executeUpdate();⑴ [6bK>w"v
//ps.addBatch();⑵ |JpLMUG
} w3^>{2iqq
//int [] counts = ps.executeBatch();⑶ ;tS 4h
conn.commit(); mSWh'1]b.~
}catch(Exception e){ fbbk;Rq.'3
e.printStackTrace(); x)X=sX.
} finally{ H8>u:
try{ w$JG:y#
if(ps!=null) { ))M; .b.D
ps.clearParameters(); Pkr0|bs*
ps.close(); 1|za>N6[yu
ps=null; _T\~AwVc<
} YN\!I
}catch(SQLException e){} rb+&]
DBUtils.closeConnection(conn); 2:(h17So
} ^&o38=70*
} =] R_6#
public long getLast(){ a0Y/,S*K
return lastExecuteTime; ! H)D@,@ &
} !6t
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public void run(){ N'L3Oa\%
long now = System.currentTimeMillis(); @"*8nV#
if ((now - lastExecuteTime) > executeSep) { x(e=@/qp
//System.out.print("lastExecuteTime:"+lastExecuteTime); OzFA>FK0f;
//System.out.print(" now:"+now+"\n"); WJG& `PP
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); yqpb_h9
lastExecuteTime=now; EJ*
executeUpdate(); x,Im%!h
} PvzB, 2":
else{ *D: wwJ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} q?x.P2
} *QzoBpO<
} i,=CnZCh
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 b|i94y(
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类写好了,下面是在JSP中如下调用。 QdM&M^
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<% /aepE~T
CountBean cb=new CountBean(); 90%alG1>y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )v!>U<eprD
CountCache.add(cb); D`=hP(y^
out.print(CountCache.list.size()+"<br>"); QI@!QU$K&
CountControl c=new CountControl(); 9JHu{r"M
c.run(); 6?U2Et
out.print(CountCache.list.size()+"<br>"); .P[
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