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: Rq,Fp/
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CountBean.java
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/* }`D-]/T8.
* CountData.java Ahrtl6@AS
* -A)/CFIZ
* Created on 2007年1月1日, 下午4:44 qY|NA)E)Bp
* "<1-9CMl
* To change this template, choose Tools | Options and locate the template under Vo(V<2lw}
* the Source Creation and Management node. Right-click the template and choose _NB8>v
* Open. You can then make changes to the template in the Source Editor. G:Cgq\+R
*/
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package com.tot.count; Fu"@)xw/-q
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/** *}Nh7>d(
* !?J?R-C
* @author :B1a2Y^"
*/ 7oFA5T _
public class CountBean { ah|`),o(k
private String countType; X:d[eAu0
int countId; Qm2(Z8Gh
/** Creates a new instance of CountData */ <hzuPi@
public CountBean() {} A]AM|2 D
public void setCountType(String countTypes){ y>|AX/n
this.countType=countTypes; 06fs,!Q@
} w$FN(BfA
public void setCountId(int countIds){ >&l{_b\k
this.countId=countIds; K])|
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} 0uO<7IW9
public String getCountType(){ ky0,#ZOF
return countType; *D;VZs0O
} H'wh0K(
public int getCountId(){ 6I~{~YvB"
return countId; u,),kj<
} k=JT%
} F >co#
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CountCache.java q($fl7}Y
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/* {pM3f
* CountCache.java tqT-9sEXX.
* .aE%z/@s=
* Created on 2007年1月1日, 下午5:01 >TddKR@C
* FaA7m
* To change this template, choose Tools | Options and locate the template under i*ji
* the Source Creation and Management node. Right-click the template and choose ?Qdp#K]WX
* Open. You can then make changes to the template in the Source Editor. ]WZi +
*/ iWMgU:T
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package com.tot.count; dxF/]>t
import java.util.*; I<L<xwh1(E
/** uc-Go
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* n9r3CLb[
* @author 2mVLR;s{_
*/ ~ZXAW~a}
public class CountCache { aFV d}RO0
public static LinkedList list=new LinkedList(); >? ({
/** Creates a new instance of CountCache */ R;Gf3K
public CountCache() {} 3-$w5O3}
public static void add(CountBean cb){ HP*AN@>Kw
if(cb!=null){ |,OTGZgc
list.add(cb); Ehf3L |9
} B(U0 ~{7a
} }Q%fY(bp
} 1PdxoRa4=
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CountControl.java MtIhpTX
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/* z]F4Z'(e.
* CountThread.java 32ae? d
* P
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* Created on 2007年1月1日, 下午4:57 AC9#!#
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* mB]Y;R<
* To change this template, choose Tools | Options and locate the template under \J?5Kl[*c
* the Source Creation and Management node. Right-click the template and choose >5}jM5$
* Open. You can then make changes to the template in the Source Editor. Dt8wd,B
*/ HRZ3}8Qj
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package com.tot.count; |?
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import tot.db.DBUtils; SK_i 3?
import java.sql.*; +i.b&PF'H
/** bLpGrGJs
* ?{M!syD<
* @author 9dXtugp|
*/ /"%QIy'{
public class CountControl{ Il9pL~u
private static long lastExecuteTime=0;//上次更新时间 O`W&`B(*k
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 j2"Y{6c
/** Creates a new instance of CountThread */ 1F_ 1bAh$
public CountControl() {} zPT!Fa`
public synchronized void executeUpdate(){ %xWscA%^u
Connection conn=null; ;Z(~;D
PreparedStatement ps=null; hSyA;*)U
try{ ViG4tb
conn = DBUtils.getConnection(); M`kR2NCi
conn.setAutoCommit(false); sCF7K=a
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *|DIG{
for(int i=0;i<CountCache.list.size();i++){ `nDgwp:b"
CountBean cb=(CountBean)CountCache.list.getFirst(); 1*Ui=M4
CountCache.list.removeFirst(); >{]mN5
ps.setInt(1, cb.getCountId()); qg;fh]j%
ps.executeUpdate();⑴ %<Q?|}
//ps.addBatch();⑵ Bz#K_S
} 63?fn~0\
//int [] counts = ps.executeBatch();⑶ %7oB[2
conn.commit(); $@blP<I
}catch(Exception e){ 2o5v{W
e.printStackTrace(); K?o} B
} finally{ 4x
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try{ C^x+'. ^N
if(ps!=null) { g)Byd\DS
ps.clearParameters(); "nK(+Z
ps.close();
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ps=null; &i~AXNw
} ceu}Lp^%/
}catch(SQLException e){} \4.U.pKY
DBUtils.closeConnection(conn); T8i9
} ZP&"[_
} Q`]El<$
public long getLast(){ kFG>Km(y}
return lastExecuteTime; hp E?
} S6sw)
public void run(){ \KaWR
long now = System.currentTimeMillis(); |,ZmRW^2K
if ((now - lastExecuteTime) > executeSep) {
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//System.out.print("lastExecuteTime:"+lastExecuteTime); K"sfN~@rT[
//System.out.print(" now:"+now+"\n"); KR6*)?c`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); NgnHo\)
lastExecuteTime=now; <E|K<}W#
executeUpdate(); bTn7$EG
} L:y}
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else{ syYg, G[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Hop$w
} 3 9Ql|l$
} fFfH9 cl!
} 2>l:: 8Pp
//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 AVR9G^ce_
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类写好了,下面是在JSP中如下调用。 ~nk'ZJ
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<% $e|G#mMd-
CountBean cb=new CountBean(); OT9\K_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {q1&4U~'>O
CountCache.add(cb); S4]xxc
out.print(CountCache.list.size()+"<br>"); gq6C6
CountControl c=new CountControl(); [Pdm1]":(
c.run(); r'p;Nj.
out.print(CountCache.list.size()+"<br>"); $+<X 1
%>