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: [SluYmW
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CountBean.java qOyg&]7
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/* =Q % F~
* CountData.java *c\:ogd
* D[.;-4"_
* Created on 2007年1月1日, 下午4:44 {Z>OAR#
* X 8TwMt
* To change this template, choose Tools | Options and locate the template under 8 |2QJ
* the Source Creation and Management node. Right-click the template and choose ";jj`
* Open. You can then make changes to the template in the Source Editor. \r_-gn'1b
*/ O-rHfIxY
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package com.tot.count; 29]T:I1d[
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/** "=7y6bM
* xLfx/&2
* @author k79"xyXX
*/ ogt<vng
public class CountBean { R %QgOz3`
private String countType; 9{gY|2R_
int countId; 6}aIb .j
/** Creates a new instance of CountData */ "Qf X&'09
public CountBean() {} 95.m^~5
public void setCountType(String countTypes){ jU1 ([(?"
this.countType=countTypes; ?8cgQf$
} D49yV`
public void setCountId(int countIds){ ;a]2hd"6
this.countId=countIds; j@jaFsX|
} S>W_p~@
public String getCountType(){ Z.a`S~U
return countType; CzP?J36W^
} 3`ov?T(H
public int getCountId(){ jhd&\z-
return countId; b'
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} oy I8}s:
} 5iE-$,7#L
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CountCache.java 3h:"-{MW.
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/* \,YF['Qq
* CountCache.java ),#%jc2_^
* <ID/\Qx`q
* Created on 2007年1月1日, 下午5:01 MfJ;":]O!
* X.u&4SH
* To change this template, choose Tools | Options and locate the template under `XAlzI
* the Source Creation and Management node. Right-click the template and choose B}Q.Is5
* Open. You can then make changes to the template in the Source Editor. un{LwZH
*/ _9%R
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package com.tot.count; ]a4rA+NFLB
import java.util.*; 89*txYmx
/** Qh4@Nl#Ncf
* ~x:\xQti
* @author Ks|qJ3;
*/ muMb pF
public class CountCache { ZWZRG-:&H
public static LinkedList list=new LinkedList(); ZPrL)']
/** Creates a new instance of CountCache */ ~ YQC!x
public CountCache() {} Czj]jA(0f
public static void add(CountBean cb){ 7 &y'\
if(cb!=null){ D6cqON0a.
list.add(cb); [ML%u$-
} oBfh1/<<a
} "bI'XaSv
} *VJT]^_
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CountControl.java !q:[$g-@q
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/* LxWnPi ^
* CountThread.java $a^YJY^_
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* Created on 2007年1月1日, 下午4:57 &L&6y()G
* J$'Q3k
* To change this template, choose Tools | Options and locate the template under gIGyY7{(s8
* the Source Creation and Management node. Right-click the template and choose SFKfsb !C
* Open. You can then make changes to the template in the Source Editor. Q8]lz}
*/ X
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package com.tot.count; xq#YBi,
import tot.db.DBUtils; N3J T[7
import java.sql.*; uB;\nj5'D
/** z[zURj-*]
*
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* @author ]: VR3e"H
*/ mMp(
public class CountControl{ A1VbqA
private static long lastExecuteTime=0;//上次更新时间 y5" b(nb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 dD%Sbb
/** Creates a new instance of CountThread */ j2@19YXe@
public CountControl() {} /Y NV
public synchronized void executeUpdate(){ ;ps0wswX
Connection conn=null; 6N7^`ghTf
PreparedStatement ps=null; jc%
try{ %}T' 3
conn = DBUtils.getConnection(); lB7 V4
conn.setAutoCommit(false); QqpXUyHp[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); F]_w~1
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for(int i=0;i<CountCache.list.size();i++){ :Z(w,
CountBean cb=(CountBean)CountCache.list.getFirst(); oqLM-=0<}
CountCache.list.removeFirst(); dRl*rP/
ps.setInt(1, cb.getCountId()); Wt$" f
ps.executeUpdate();⑴ WA~PE` U
//ps.addBatch();⑵ PubO|Mf
} lCyBdY9n
//int [] counts = ps.executeBatch();⑶ adi^*7Q] )
conn.commit(); R^[b
I;
}catch(Exception e){ [(*ObvEF
e.printStackTrace(); &bh%>[
} finally{ <=1nr@L
try{ H1!u1k1nl
if(ps!=null) { ;nzzt~aCC
ps.clearParameters(); PWavq?SR
ps.close(); s{QS2G$5
ps=null; w;e42.\
} #*J+4aw3
}catch(SQLException e){} 2u B66i
DBUtils.closeConnection(conn); V:<NQd
} 6[\b]I\Q
} Xs,[Z2_iq
public long getLast(){ {x&"b -
return lastExecuteTime; >gj%q$@
} AeQIsrAHE
public void run(){ Ptj,9bf<\
long now = System.currentTimeMillis(); S"}G/lBx.
if ((now - lastExecuteTime) > executeSep) { @ V_@r@A
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;v}f7v '
//System.out.print(" now:"+now+"\n"); M1>2Q[h7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); z8MKGM
lastExecuteTime=now; }&E'ox<S
executeUpdate(); ]]R!MnU:$
} @<^_ _."
else{ (x+C=1,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); h;s~I/e(
} Mk:k0,z
} ^@"H(1Hxu/
} APne!
//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 D@-'<0=
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类写好了,下面是在JSP中如下调用。 \A~r~
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<% fo$5WTY
CountBean cb=new CountBean(); 58v q5j<V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >vr!3
CountCache.add(cb); S2^Ckg
out.print(CountCache.list.size()+"<br>"); IY* ~df
CountControl c=new CountControl(); 4`KQ@m
c.run(); W*S!}ZT`
out.print(CountCache.list.size()+"<br>"); ;!k{{Xndd
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