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: M%#e1"n
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CountBean.java Kpp_|2|@<
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/* >sbu<|]a
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* CountData.java S>{~nOYt-`
* q(}bfIf
* Created on 2007年1月1日, 下午4:44 'q.!|G2U
* B<-Wea
* To change this template, choose Tools | Options and locate the template under (.,G=\!
* the Source Creation and Management node. Right-click the template and choose >3bCTE
* Open. You can then make changes to the template in the Source Editor. ,?3G;-
*/ z{>Rc"%\
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package com.tot.count; 8>V5dEbx'
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/** I:.s_8mH}
* %znc##j)q
* @author v,t:+
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*/ ]R *A
public class CountBean { @PU [:;
private String countType; s`UJ1eJ
int countId; _*zt=zn>
/** Creates a new instance of CountData */ vv7I_nK?
public CountBean() {} OJxl<Q=z
public void setCountType(String countTypes){ }\LQ3y"[
this.countType=countTypes; 8i pez/
} Debv4Gr;^
public void setCountId(int countIds){ $8FUfJ1@
this.countId=countIds; snJ129}A
} 7o4\oRGV
public String getCountType(){ 3a|\dav%
return countType; m kexc~l
} oU/5 a>9~
public int getCountId(){ cNH7C"@GVu
return countId; _G0x3
} 54/=G(F
} (w{j6).3Dj
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CountCache.java -HuA
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/* wS*E(IAl
* CountCache.java Y ay?=Y{
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* Created on 2007年1月1日, 下午5:01 N;gfbh]
* ;\]@K6m/Ap
* To change this template, choose Tools | Options and locate the template under 9VT;ep
* the Source Creation and Management node. Right-click the template and choose Je{ykL?N
* Open. You can then make changes to the template in the Source Editor. ME dWLFf
*/ ww/Uzv
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package com.tot.count; u4j5w
import java.util.*; Q20%"&Xp]
/** P%zK;#8V
* CWlw0X
* @author M`>E|"<
*/ 1"g<0
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public class CountCache { >V~E]P%@
public static LinkedList list=new LinkedList(); :-'qC8C
/** Creates a new instance of CountCache */ ]{iQ21`a-
public CountCache() {} #*}+J3/
public static void add(CountBean cb){ "}!G!k:
if(cb!=null){ HV.t6@\};
list.add(cb); &NWEqBz*2
} nK,w]{<wG!
} hQi2U
} }*-@!wc-N
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CountControl.java Uv.)?YeGh
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/* %LV9=!w
* CountThread.java ..qCPlK;
*
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* Created on 2007年1月1日, 下午4:57 G?ZXWu.
* Y7aqO5
* To change this template, choose Tools | Options and locate the template under /NlGFO*Z
* the Source Creation and Management node. Right-click the template and choose yw!{MO
* Open. You can then make changes to the template in the Source Editor. ]3gSQ7
*/ Qd-A.{[h
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package com.tot.count; dscgj5b1~
import tot.db.DBUtils; ,^:.dFH6
import java.sql.*; [~^0gAlQC
/** ;I*o@x_
* T|p"0b A
* @author ]q.0!lh+WL
*/ ZEQ Ex]Y
public class CountControl{ s>en
private static long lastExecuteTime=0;//上次更新时间 H. c7Nle
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 25T18&R
/** Creates a new instance of CountThread */ G"6 !{4g
public CountControl() {} O}P`P'Y|'
public synchronized void executeUpdate(){ *fdTpXa
Connection conn=null; KP"+e:a%
PreparedStatement ps=null; Rv=YFo[B
try{ Vj-h;rB0z
conn = DBUtils.getConnection(); Th%zn2R B
conn.setAutoCommit(false); <[phnU^
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); yuVs
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for(int i=0;i<CountCache.list.size();i++){ GmG5[?)
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); y(&Ac[foS}
ps.setInt(1, cb.getCountId()); 6mE\OS-I
ps.executeUpdate();⑴ y2v^-q3
//ps.addBatch();⑵ iwq!w6+
} TV:9bn?r)
//int [] counts = ps.executeBatch();⑶ GeqPRah
conn.commit(); :Al!1BJQ
}catch(Exception e){ O8o3O
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e.printStackTrace(); cR{#V1Z
} finally{ u!s2BC0}N
try{ .6> w'F{>
if(ps!=null) { z{6Z
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ps.clearParameters(); %C0Dw\A*:
ps.close(); ibw;}^m(
ps=null; L-Lvp%%
} >usL*b0%
}catch(SQLException e){} =v\.h=~~
DBUtils.closeConnection(conn); LscGTs,
} *R"/ |Ka
} O<I-
public long getLast(){ lFkR=!?=
return lastExecuteTime; 0%B/,/PxD
} s*4dxnS_8
public void run(){ 3
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long now = System.currentTimeMillis(); <$YlH@;)`a
if ((now - lastExecuteTime) > executeSep) { vIvIfE
//System.out.print("lastExecuteTime:"+lastExecuteTime); "N;EL0=
//System.out.print(" now:"+now+"\n"); >ef6{URy<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6LZCgdS{
lastExecuteTime=now; H+#FSdy#
executeUpdate(); t7pFW^&
} &[9709 (=
else{ r^ XVB`v
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); jCY%|
} :]"V-1#}
} {I((p_
} _GPe<H
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 <%^&2UMg
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类写好了,下面是在JSP中如下调用。 xLE)/}y_7H
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<% 7^Uv7<pw
CountBean cb=new CountBean(); SJLis"8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); sT.ss$HY9,
CountCache.add(cb); TvM~y\s
out.print(CountCache.list.size()+"<br>"); 2eogY#
CountControl c=new CountControl(); q)GdD==
c.run(); :3PH8TL
out.print(CountCache.list.size()+"<br>"); +t.b` U`-
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