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: CoV@{Pi
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CountBean.java 0R;`)V\^
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/* Hp@cBj_@P2
* CountData.java ~ujg250.L
* X{iidTW`xv
* Created on 2007年1月1日, 下午4:44 @ev^e!B
* +&*>FeJY
* To change this template, choose Tools | Options and locate the template under a
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* the Source Creation and Management node. Right-click the template and choose iZ0.rcQj'o
* Open. You can then make changes to the template in the Source Editor. KP!7hJhw
*/ O]l-4X#8F
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package com.tot.count; Q'[~$~&`
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/** w$`u_P|@E:
* I.o3Old
* @author ltHuN;C\
*/ n.A*(@noe
public class CountBean { ;1k_J~Qei
private String countType; xM>dv5<E
int countId; [-\DC*6
/** Creates a new instance of CountData */ jRp @-S#V
public CountBean() {} sA
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public void setCountType(String countTypes){ Cyud)BZvm
this.countType=countTypes; G
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} hysxHOL
public void setCountId(int countIds){ \\/
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this.countId=countIds; nTsPX Tat
} 3]>YBbXvE
public String getCountType(){ P.~sNd oJ
return countType; {h;i x
} `KE(R8y
public int getCountId(){ 7>gW2m
return countId; Si|8xq$E;
} t5QGXj
} O>ZJOKe
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CountCache.java hG3RZN#ejq
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/* gIcPKj"8${
* CountCache.java ]xhH:kW4
* %Jn5M(myC
* Created on 2007年1月1日, 下午5:01 d_98%U+u
* 5hB2:$C
* To change this template, choose Tools | Options and locate the template under DE?@8k
* the Source Creation and Management node. Right-click the template and choose b{W ,wn
* Open. You can then make changes to the template in the Source Editor. 7.C]ZcU
*/ ^Cg@'R9
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package com.tot.count; ,->
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import java.util.*; 7wqD_Xr
/** Z8pZm`g)T
* Kw>gg
* @author E}]SGU"
*/ #elaz8 5
public class CountCache { E
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public static LinkedList list=new LinkedList(); *1}vn%wvn
/** Creates a new instance of CountCache */ ^N~Jm&I
public CountCache() {} :wJ!rn,4
public static void add(CountBean cb){ m>b
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if(cb!=null){ W*D*\E
list.add(cb); F#{PJ#
} 9a.[>4}
} q{.~=~
} taOsC!Bp
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CountControl.java x[%% )[d
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/* ,@2d4eg4
* CountThread.java Vs[!WJ
7
* \y/+H
* Created on 2007年1月1日, 下午4:57 JDC,]
* 5TdI
* To change this template, choose Tools | Options and locate the template under W&^2Fb
* the Source Creation and Management node. Right-click the template and choose M~!LjJg;
* Open. You can then make changes to the template in the Source Editor. B?_ujH80m
*/ m<22E0=g
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package com.tot.count; @aGS~^Uh
import tot.db.DBUtils; Mq,_DQ
import java.sql.*; vGPaW YV
/** )5bdWJ>l
* ,#-^
* @author 9a_(_g>S
*/ /t?(IcP5
public class CountControl{ @i:_JOl
private static long lastExecuteTime=0;//上次更新时间 or]s
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 on1mu't_;
/** Creates a new instance of CountThread */ <kor;exeJ
public CountControl() {} %u|qAF2uS
public synchronized void executeUpdate(){ ~LzTqMHM
Connection conn=null; k)USLA
PreparedStatement ps=null; r,dxW5v.
try{ 8%#uZG\}
conn = DBUtils.getConnection(); BF6H_g
conn.setAutoCommit(false); ihhnB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 3'2}F%!Mv
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); s/'gl
CountCache.list.removeFirst(); & ~[%N
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ps.setInt(1, cb.getCountId()); Wkv**X}
ps.executeUpdate();⑴ dUJNr_
//ps.addBatch();⑵ g@"6QAP
} h Tn^:%(
//int [] counts = ps.executeBatch();⑶ )O%lh
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conn.commit(); 9uREbip
}catch(Exception e){ -nT+!3A8
e.printStackTrace(); 3/@'tLtN
} finally{ cWM|COXL+
try{ I@q>ES!1H
if(ps!=null) { O"9f^y*
ps.clearParameters(); Z_Ma|V?6
ps.close(); }Mo9r4}
ps=null; %jM|*^\%
} L7%'Y}1e.
}catch(SQLException e){} z:R2Wksg
DBUtils.closeConnection(conn); 4%j&]PASa1
} HwSPOII|8K
} n*6',BY
public long getLast(){ fhn0^Qc"+
return lastExecuteTime; Tm^zoVi
} AjANuyUaP
public void run(){ Fk(0q/b
long now = System.currentTimeMillis(); z_l3=7R
if ((now - lastExecuteTime) > executeSep) { E(U}$Zey
//System.out.print("lastExecuteTime:"+lastExecuteTime); ddHIP`wb
//System.out.print(" now:"+now+"\n"); qkUr5^1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); JT^E`<nn
lastExecuteTime=now; c)E[K-u
executeUpdate(); I}v'n{5(
} j)IK
else{ n7q-)Dv_U
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ?3z+|;t6C
} IL:"]`f*
} A1ebXXD)
} \a]\jZb
//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 t1Khf
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类写好了,下面是在JSP中如下调用。 0XYO2k
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<% X-{:.9
CountBean cb=new CountBean(); BK d(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \
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CountCache.add(cb); EJtU(HmW
out.print(CountCache.list.size()+"<br>"); Z#MODf0H@
CountControl c=new CountControl(); BtHvfoT
c.run(); AYZds >#Q
out.print(CountCache.list.size()+"<br>"); LMG\jc?,
%>