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: %hN(79:g
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CountBean.java vq.o;q /
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/* tQRbNY#}Z
* CountData.java B9[vv;lzu
* _KKux3a
* Created on 2007年1月1日, 下午4:44 |&xaV-b9W
* Nsq=1)
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* To change this template, choose Tools | Options and locate the template under Ph%ylS/T{
* the Source Creation and Management node. Right-click the template and choose S7WHOr9XMV
* Open. You can then make changes to the template in the Source Editor. [[]yQ
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*/ Pz[UAJ
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package com.tot.count; \!30t1EZ
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/** 5z9hcQAS
* &WLN
* @author Z.!<YfA)
*/ wr:W}Z@pL
public class CountBean { I4+1P1z
private String countType; 38m9t'
int countId; 5._QI/d)'J
/** Creates a new instance of CountData */ aMGh$\Pg
public CountBean() {} 0^Vw^]w
public void setCountType(String countTypes){ SP<Sv8Okj
this.countType=countTypes; m1jEky(
} u{&=$[;
public void setCountId(int countIds){ lhJY]tQt/
this.countId=countIds; @%2crJnkS
} )m3emMO2
public String getCountType(){ WRkuPj2
return countType; ,mvFeo;@f
} -zMvpe-am&
public int getCountId(){ ~PQR_?1
return countId; IKnf
} #o[n.
} Sin)]zG~0
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CountCache.java m<z?6VC
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/* ;`c:Law4
* CountCache.java ewN|">WXQ
* 17c`c.yP
* Created on 2007年1月1日, 下午5:01 0%,W5w
* 87 B$
* To change this template, choose Tools | Options and locate the template under 2-qWR<E
* the Source Creation and Management node. Right-click the template and choose .t>SbGC
* Open. You can then make changes to the template in the Source Editor. c)N_"#&
*/ bA Yp }
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package com.tot.count; |x1Ttr,
import java.util.*; uEr.LCAS
/** h(}#s1Fzq
* %La/E#
* @author zA$ Y@f
*/ z=>P jIW
public class CountCache { s0vcGh#w
public static LinkedList list=new LinkedList(); k5tyOk
/** Creates a new instance of CountCache */ rfQs
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public CountCache() {} y
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public static void add(CountBean cb){ v,N!cp1
if(cb!=null){ &WAU[{4W
list.add(cb); [:e>FXV
} Wt!;Y,1s
} `WC4:8
} !IC
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CountControl.java @q]!C5
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/* K^GvU 0\
* CountThread.java d/3&3>/
* HlkjyD8
* Created on 2007年1月1日, 下午4:57 gGA5xkA
* ;YQ6X>
* To change this template, choose Tools | Options and locate the template under cw~GH
* the Source Creation and Management node. Right-click the template and choose X,o ]tgg=
* Open. You can then make changes to the template in the Source Editor. =8p[ (<F=
*/ kaR55
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package com.tot.count; 6OPNP0@r
import tot.db.DBUtils; lu.xv6+
import java.sql.*; hN1[*cF
/** DX3jE p2
* 7|"G
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* @author (lYC2i_b#
*/ V)`Q0}
public class CountControl{ D,-L!P
private static long lastExecuteTime=0;//上次更新时间 [czWUD
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }!s$
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/** Creates a new instance of CountThread */ O,J,Q|`H&
public CountControl() {} ;yZY2)L
public synchronized void executeUpdate(){ <bv9X?U
Connection conn=null; .fhfO @
PreparedStatement ps=null; GBd
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try{ /~<Przw
conn = DBUtils.getConnection(); iHo0:J~
conn.setAutoCommit(false); }zeKf/?'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )5;|mV
for(int i=0;i<CountCache.list.size();i++){ X)9|ZF2`
CountBean cb=(CountBean)CountCache.list.getFirst(); )s 1
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CountCache.list.removeFirst(); Dp@m"_1`+
ps.setInt(1, cb.getCountId()); 2PSv3?".
ps.executeUpdate();⑴ cetlr
//ps.addBatch();⑵ ,Qe`(vU*s
} Gn10)Uf8X
//int [] counts = ps.executeBatch();⑶ dUceZmAl
conn.commit(); aMJ9U)wnK
}catch(Exception e){ wLQM]$O
e.printStackTrace(); 3URrK[%x`
} finally{ /dVcNo3"
try{ ,}Ic($To
if(ps!=null) { d
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ps.clearParameters(); hJ V*
ps.close(); :Sk<0VVd7
ps=null; ~BI! l
} ,76nDXy`
}catch(SQLException e){} N_.`5I;e
DBUtils.closeConnection(conn); 9>5]y}.{
} -32.g\]
} !{oP'8Ax$
public long getLast(){ >LR+dShG
return lastExecuteTime; kca Y
} =(5}0}j
public void run(){ hN:2(x
long now = System.currentTimeMillis(); ~x+24/qT
if ((now - lastExecuteTime) > executeSep) { jZ69sDhE
//System.out.print("lastExecuteTime:"+lastExecuteTime); @/?$ ZX/e[
//System.out.print(" now:"+now+"\n"); 2)
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ga91#NWgK
lastExecuteTime=now; C?b_E
executeUpdate(); W&a<Q)o*I
} ( e(<4-&
else{ <.6$zcW
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); "[]72PC
} *
@j#13.
} <H!;/p/S
} uwb>q"M
//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 RD p(Ci
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类写好了,下面是在JSP中如下调用。 V|dKKb[Lve
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<% BhJ~ jV"
CountBean cb=new CountBean(); T k>N4yq
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); FY]z*=
CountCache.add(cb); ldm=uW
out.print(CountCache.list.size()+"<br>"); qdVExO&
CountControl c=new CountControl(); ~x}=lK N
c.run(); #9Dixsl*Q
out.print(CountCache.list.size()+"<br>"); Fop"m/
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