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: k t#fMd$
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CountBean.java /8'NG6"H`
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/* q>_.[+6
* CountData.java XSB"{H>&
* 6_o*y8s.
* Created on 2007年1月1日, 下午4:44 5vQHhwO50k
* s[>,X#7 y
* To change this template, choose Tools | Options and locate the template under mthA4sz
* the Source Creation and Management node. Right-click the template and choose n&4N[Qlv,
* Open. You can then make changes to the template in the Source Editor. CZwXTHe
*/ XX TL..
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package com.tot.count; #lo6c;*m5
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/** 0],r0
* NG=-NxEcN
* @author :`#d:.@]o@
*/ QO:!p5^:
public class CountBean { /{J4:N'B>
private String countType; d'gfQlDny
int countId; F~vuM$+d
/** Creates a new instance of CountData */ R_cA:3qc~
public CountBean() {} x;KOqfawv
public void setCountType(String countTypes){ AR%4D3Dma
this.countType=countTypes; Tk[ $5u*,
} p$c6<'UqH
public void setCountId(int countIds){ Dj?> <@
this.countId=countIds; [85spub&}
} ($MlX BI
public String getCountType(){ @gEUm_#HTs
return countType; D/gw .XYL
} .hb:s,0mP
public int getCountId(){ 5V~oIL
return countId; C
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} Qy<P463A(l
} 8FK/~,I
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CountCache.java $rBq"u=,0+
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/* 05#1w#i
* CountCache.java F,F4nw<W
* qA7>vi%
* Created on 2007年1月1日, 下午5:01 k"%~"9
* 2zA4vZkbcw
* To change this template, choose Tools | Options and locate the template under |Zpfq63W
* the Source Creation and Management node. Right-click the template and choose *;slV3
* Open. You can then make changes to the template in the Source Editor. +o{R _
*/ M/'sl;
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package com.tot.count; O63<AY@
import java.util.*; 2wg5#i
/** )EuvRLo{S7
* I_#kgp
* @author ^/>(6>S^M
*/
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public class CountCache { mDABH@R
public static LinkedList list=new LinkedList(); #G|RnV%t$~
/** Creates a new instance of CountCache */ =o(5_S.u;
public CountCache() {} 9&2O9Nz6
public static void add(CountBean cb){ X7MM2V
if(cb!=null){ lv<*7BCp
list.add(cb); 0S_~ \t
} dL 1tl
} 4[r0G+
} myQagqRx
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CountControl.java nNV'O(x}
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/* Fnv;^}\z
* CountThread.java %N6A+5H
* ~
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* Created on 2007年1月1日, 下午4:57 ~$cV:O7
* Lx1FpHo
* To change this template, choose Tools | Options and locate the template under ,kGc]{'W
* the Source Creation and Management node. Right-click the template and choose `2WFk8) F
* Open. You can then make changes to the template in the Source Editor. )[6U^j4
*/ ZY= {8T@
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package com.tot.count; #U4F0BdA
import tot.db.DBUtils; Gr'
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import java.sql.*; L#?Ek-
/** h 8S. x)
* 4r#= *
* @author hbDXo:
*/ -HbC!wv
public class CountControl{ [A~xy'T
private static long lastExecuteTime=0;//上次更新时间 iRbT/cc{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -#[a7',Z;
/** Creates a new instance of CountThread */ 6dt]`zv/
public CountControl() {} z+wA
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public synchronized void executeUpdate(){ G@\1E+Ip
Connection conn=null; }5[qo`M
PreparedStatement ps=null; / }X1W
try{ '~<m~UXvD#
conn = DBUtils.getConnection(); #aJ(m&
conn.setAutoCommit(false); sN*N&XG
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); . B9iLI
for(int i=0;i<CountCache.list.size();i++){ LVfF[
CountBean cb=(CountBean)CountCache.list.getFirst(); Ecefi
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CountCache.list.removeFirst(); &K.d'$q
ps.setInt(1, cb.getCountId()); m+R[#GE8#
ps.executeUpdate();⑴ 3?9IJ5p
//ps.addBatch();⑵ B$ PP&/
} J.b9F:&}
//int [] counts = ps.executeBatch();⑶ t;Sb/ 3
conn.commit(); NjScc%@y
}catch(Exception e){ 5"@*?X K^
e.printStackTrace(); 0B/,/KX
} finally{ Su7?;Oh/yI
try{ $\BE&4g
if(ps!=null) { S(I{NL}=$
ps.clearParameters(); ]EBxl=C}D
ps.close(); .-c4wm}
ps=null; =E4LRKn
} u#$]?($}d
}catch(SQLException e){} "Mn6U-
DBUtils.closeConnection(conn); H>IMf/%5N-
} ay
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} u@UMP@"#
public long getLast(){ =,=A,kI[;
return lastExecuteTime; 61>.vT8P
} EStB#V^
public void run(){ g`' !HGY
long now = System.currentTimeMillis(); oXh#a8
if ((now - lastExecuteTime) > executeSep) { C.yQ=\U2
//System.out.print("lastExecuteTime:"+lastExecuteTime); HGs $*
//System.out.print(" now:"+now+"\n"); 9igiZmM
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4y?n
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lastExecuteTime=now; u(>^3PJ+
executeUpdate(); p!7FpxZY
} XB^'K2
else{ Vpz\.]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <I\/n<*
} Uw. `7b>B
} 8,4"uuI
} { ]{/t-=
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 /<=u\e'rE
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类写好了,下面是在JSP中如下调用。 ]Ji.Zk
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<% vXf!G`D
CountBean cb=new CountBean(); feDlH[$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t ;;U}
CountCache.add(cb); |O|V-f{l
out.print(CountCache.list.size()+"<br>"); v6bGjVK[
CountControl c=new CountControl(); uK"=i8rs4
c.run(); !Vn\u
out.print(CountCache.list.size()+"<br>"); ghG**3xr
%>