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: o!W(
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CountBean.java =&roL7ps
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/* zAH6SaI$
* CountData.java |?4NlB6
* "WzD+<oL
* Created on 2007年1月1日, 下午4:44 -nDY3$U/
* Gm-V/[29R
* To change this template, choose Tools | Options and locate the template under z^\-x9vL
* the Source Creation and Management node. Right-click the template and choose q:u,)6
* Open. You can then make changes to the template in the Source Editor. 8Cw3b\ne
*/ Tx|y!uHh
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package com.tot.count; ZMO ym=
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/** 40HhMTZ0-
* #;/ob-
* @author ,#K{+1z:
*/ d VyT `
public class CountBean { 3U%kf<m=
private String countType; R 0YWe
int countId; K#xL-
/** Creates a new instance of CountData */ /-Z}=
public CountBean() {} e$o]f"(
public void setCountType(String countTypes){ arN=OB
this.countType=countTypes; % !Ih=DZ
} - |4 Oq
public void setCountId(int countIds){ R$i-%3
this.countId=countIds; e@7UL|12
} du_~P"[
public String getCountType(){ *1,4#8tB
return countType; 2 :wgt
} %BF,;(P
public int getCountId(){ z['2
return countId; Lwn
} bL/DjsZ@
} 8yk4#CZ
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CountCache.java XvVi)`8!u
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/* c/E'GG%Q%
* CountCache.java _RE;}1rb,
* st)qw]Dn;Y
* Created on 2007年1月1日, 下午5:01 i@mS8%|l
* i(>
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* To change this template, choose Tools | Options and locate the template under 3!vnSX(iv
* the Source Creation and Management node. Right-click the template and choose U'@ ![Fp
* Open. You can then make changes to the template in the Source Editor. z! :0%qu
*/ WV}HN
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package com.tot.count; C=qL0
import java.util.*; ch33+~Nn
/** a9NIK/9
* "EwzuM8f
* @author 8J:=@X^}
*/ % _nmv
public class CountCache { D~ n-;T
public static LinkedList list=new LinkedList(); d .%2QkL
/** Creates a new instance of CountCache */ /QT>"
public CountCache() {} _ Y7Um
public static void add(CountBean cb){ g)7@EU2
if(cb!=null){ X0]{8v%
list.add(cb); ~ +h4i'
} G|u)eW
} wsB
} .q1y)l-^Z
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CountControl.java a(X V~o
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/* ,0{x-S0jX<
* CountThread.java <<R2
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* w |abaMam
* Created on 2007年1月1日, 下午4:57 7^tYtMm|U
* $PRUzFZ
* To change this template, choose Tools | Options and locate the template under i|m8#*Hd
* the Source Creation and Management node. Right-click the template and choose @0(%ayi2Y
* Open. You can then make changes to the template in the Source Editor. LXaq
*/ u U%Z%O
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package com.tot.count; >Y(JC#M;
import tot.db.DBUtils; o`G6!
import java.sql.*; TbLU[(m-n
/** H3 -?cy
* uIBN
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* @author m |+zMf&
*/ iK'A m.o+
public class CountControl{ kaR55
private static long lastExecuteTime=0;//上次更新时间 p>pAU$k{O
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 s%>u[-9U
/** Creates a new instance of CountThread */ kaEu\@%n
public CountControl() {} 5qqU8I
public synchronized void executeUpdate(){ "4smW>f:%
Connection conn=null; e1bV&
PreparedStatement ps=null; e2;=OoBK
try{ l<sWM$ez
conn = DBUtils.getConnection(); [vY)y\W{
conn.setAutoCommit(false); p"cY/2w:j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); WwSyw?T
for(int i=0;i<CountCache.list.size();i++){ @.`HvS
CountBean cb=(CountBean)CountCache.list.getFirst(); hdM?Uoo(4a
CountCache.list.removeFirst(); *x2u
ps.setInt(1, cb.getCountId()); 3+U2oI:I
ps.executeUpdate();⑴ X88I|Z'HIh
//ps.addBatch();⑵ r[j@@[)"
} Cd p_niF
//int [] counts = ps.executeBatch();⑶ !g>mjD
conn.commit(); 5=8_Le
}catch(Exception e){ hiR+cPSF
e.printStackTrace(); u6\W"LW
} finally{ \vj xCkg{
try{ =PLy^%
if(ps!=null) { ;4oKF7]
ps.clearParameters(); a,M/i&.e`
ps.close(); mn{R>
ps=null; Xa>c]j
} X)[QEq^
}catch(SQLException e){} ;%u)~3B$JK
DBUtils.closeConnection(conn); dwzk+@]8
} V+*1?5w
} kwt;pxp i
public long getLast(){ ?0s&Kz4B
return lastExecuteTime; SnO,-Rg
} GCcSI;w
public void run(){ J/ vcP
long now = System.currentTimeMillis(); EJaO"9
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if ((now - lastExecuteTime) > executeSep) { Gn10)Uf8X
//System.out.print("lastExecuteTime:"+lastExecuteTime); A#79$[>w
//System.out.print(" now:"+now+"\n"); N *n?hN
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ><6g-+*k
lastExecuteTime=now; 1b!5h
executeUpdate(); Y3hudjhLl
} ,?GAFgK:
else{ #:
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <lSo7NkR
} DB] ]6
} d
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} [vCZD8"Y8
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 U:IeMf-;
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类写好了,下面是在JSP中如下调用。 y=}a55:qE
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<% a>nV!b\n5
CountBean cb=new CountBean(); 9>5]y}.{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ve=1y)
CountCache.add(cb); {y:+rh&
out.print(CountCache.list.size()+"<br>"); !{oP'8Ax$
CountControl c=new CountControl(); UFa 00t^5
c.run(); !P _'n
out.print(CountCache.list.size()+"<br>"); <{1 3Nd'o
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