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: kYxS~Kd<
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CountBean.java 396R$\q
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/* qSO*$1i
* CountData.java czBi Dk4
* }1%r%TikY
* Created on 2007年1月1日, 下午4:44 s([Wn)I
* *[kx F*^
* To change this template, choose Tools | Options and locate the template under %>XN%t'6aT
* the Source Creation and Management node. Right-click the template and choose c/u_KJFF-n
* Open. You can then make changes to the template in the Source Editor. (3EUy"z-
*/ hPufzhT
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package com.tot.count; C 7nKk/r
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/** Z-|li}lDr
* Wtv#h~jy9
* @author ^@}#me@
*/ {&nV4c$v
public class CountBean { B[xR-6phW
private String countType; H|+tC=]4IZ
int countId; ?B4#f!X
/** Creates a new instance of CountData */ C;sgK
public CountBean() {} 6d{j0?mM
public void setCountType(String countTypes){ DA
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this.countType=countTypes; GFR!n1Hv
} *e<_; Kr?
public void setCountId(int countIds){ V8'`nuC+
this.countId=countIds; 3B,QJ&
} *:arva5
public String getCountType(){ t]TyXAr~
return countType; ]A!.9Ko}u
}
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public int getCountId(){ cjg=nTsBA
return countId; aW@oE
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} YMAQ+A!
} w<d*#$[,*
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CountCache.java DM2Q1Dh3
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/* )Z:m)k>r;
* CountCache.java fSV5
* {mYx
* Created on 2007年1月1日, 下午5:01 f8!l7{2%q
* ~_}4jnC
* To change this template, choose Tools | Options and locate the template under 5<r)+?!n
* the Source Creation and Management node. Right-click the template and choose _5h0@^m7y
* Open. You can then make changes to the template in the Source Editor. X RRJ)}P
*/ \G=bj;&eF
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package com.tot.count;
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import java.util.*; Q2$/e+
/** m~Me^yt>}
* td/5Bmj
* @author QX/]gX
*/ B'/Icg.T
public class CountCache { x9\J1\
public static LinkedList list=new LinkedList(); h*l4Y!7
/** Creates a new instance of CountCache */ Wy,"cT
public CountCache() {} 1Q_ ``.M
public static void add(CountBean cb){ ws().IZ
if(cb!=null){ sKCGuw(mh
list.add(cb);
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} +cw{aI`a8
} j%GbgJ
} :b,o B==%
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CountControl.java bN4d:0 Y
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/* !
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* CountThread.java =jBL'|k5
* 5#BF,-Jv
* Created on 2007年1月1日, 下午4:57 0c-QIr}m
* _AAx
)
* To change this template, choose Tools | Options and locate the template under >T(M0Tkt
* the Source Creation and Management node. Right-click the template and choose 1S^'C2/b
* Open. You can then make changes to the template in the Source Editor. |H<|{{E
*/ }7&\eV{qU
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package com.tot.count; taBO4LV
import tot.db.DBUtils; e8 v; D
import java.sql.*; zAu}hVcW
/** Vzk cZK
* I_K[!4~Kn
* @author r \9:<i8
*/ }1@n(#|c
public class CountControl{ %pd5w~VP
private static long lastExecuteTime=0;//上次更新时间 S q.9-h%5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 IZ|c<#r6
/** Creates a new instance of CountThread */ E#8J+7
public CountControl() {} MyK^i2eD
public synchronized void executeUpdate(){ a_xQ~:H
Connection conn=null; M3)v-"
PreparedStatement ps=null; |c]> Q
try{ o&WRta>VP
conn = DBUtils.getConnection(); 9#s,K! !3{
conn.setAutoCommit(false); }#YIl@E
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); g2!0vB>
for(int i=0;i<CountCache.list.size();i++){ (di)`D5Q
CountBean cb=(CountBean)CountCache.list.getFirst(); Cq
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CountCache.list.removeFirst(); 7^`RP e^a+
ps.setInt(1, cb.getCountId()); aS3P(s L
ps.executeUpdate();⑴ :17ee
//ps.addBatch();⑵ 7 _X&5ni
} 9Kq<\"7Bmz
//int [] counts = ps.executeBatch();⑶ pq%t@j(X
conn.commit(); &8R-C[A
}catch(Exception e){ ;:-}z.7Y
e.printStackTrace(); Oz_b3r
} finally{ <m-Ni
try{ n5/ZJur
if(ps!=null) { X%RQB$
ps.clearParameters(); pb,{$A
ps.close(); >1_Dk7E0D
ps=null; 8JQ<LrIt9
} l6r%nHP@
}catch(SQLException e){} [~zE,!
DBUtils.closeConnection(conn); 2
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} y}3
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} BBaHMsr
public long getLast(){ B3ohHxHu
return lastExecuteTime; C@l +\M(
} 0Og/47dO.2
public void run(){ Lh8#I&x
long now = System.currentTimeMillis(); ~hxeD" w
if ((now - lastExecuteTime) > executeSep) { +]aD^N9['
//System.out.print("lastExecuteTime:"+lastExecuteTime); ua6*zop
//System.out.print(" now:"+now+"\n"); MVu[gB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !XG/,)A
lastExecuteTime=now; tSw~_s_V
executeUpdate(); $i5G7b
} O&gy(
else{ *,Aa9wa{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L%=BCmMx
} bCe[nmE2
} [qc6Q:
} g[uE@Gaj&
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ,cl"1>lp
C/grrw
类写好了,下面是在JSP中如下调用。 Y6[] wUJ
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<% T`0`]z !~
CountBean cb=new CountBean(); \Ho#[k=y*/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 'RN"yMv7l
CountCache.add(cb); Hf`&&
out.print(CountCache.list.size()+"<br>"); /eI,]CB'z
CountControl c=new CountControl(); b W`)CWd
c.run(); g]TI8&tP!L
out.print(CountCache.list.size()+"<br>"); .5$V7t.t$\
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