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: :'fK`G
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CountBean.java **6X9ZIX[
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/* XC390t
* CountData.java y|9 LtQ
* G&M)n*o
* Created on 2007年1月1日, 下午4:44 >%_i#|dE>
* ]i
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* To change this template, choose Tools | Options and locate the template under rXe+#`m2
* the Source Creation and Management node. Right-click the template and choose chE}`I?
* Open. You can then make changes to the template in the Source Editor. P;&U3i
*/ NX]6RZr-
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package com.tot.count; 3rX8H`R
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/** ,S, R6#3G
* V|nJ%G\
* @author xFp9H'j{
*/ "68=dC
public class CountBean { A/j'{X!z
private String countType; ,p..h+l
int countId; O7,:-5h0
/** Creates a new instance of CountData */ ?DNeL;6
public CountBean() {} E`iE]O
public void setCountType(String countTypes){ lx82:_
this.countType=countTypes; y] $-:^
} ,qdZ6bv,]|
public void setCountId(int countIds){ H
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this.countId=countIds; f-}_
} >Y:veEa6v6
public String getCountType(){ (1Jc-`
return countType; KDDx[]1Q
} 0=OvVU;P
public int getCountId(){ o 7 &q
return countId; f_QZql
} HNfd[#gV
} ~@D!E/hZx
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CountCache.java Y3'dV)
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/* 2-"`%rE
* CountCache.java MPsm)jqX
* 9v}vCg
* Created on 2007年1月1日, 下午5:01 fEyc3K'5V
* h&bs`
* To change this template, choose Tools | Options and locate the template under ^"$~&\+x5
* the Source Creation and Management node. Right-click the template and choose ;,u7)
* Open. You can then make changes to the template in the Source Editor. x&FBh!5H
*/ <L3ig%#B
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package com.tot.count; F;Ubdxwwl
import java.util.*; `{S4_'
/** _#o75*42tT
* r9^~I
* @author TIP H#W:v
*/ ? ~_h3bHH
public class CountCache { Vvl8P|x.<
public static LinkedList list=new LinkedList(); byj7c(
/** Creates a new instance of CountCache */ YzAGhAyw
public CountCache() {} hB]<li)"C
public static void add(CountBean cb){ Ng1[y4R}
if(cb!=null){ X.ZY1vO
list.add(cb); UTuOean ]'
} 62/tg*)
} sRGIHT#
} V"sm+0J
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CountControl.java k=5v
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/* l`AA<Rj*O-
* CountThread.java Be0v&Q_NK
* |DoD.?v
* Created on 2007年1月1日, 下午4:57 5'3H$%dC
* T4"*w
* To change this template, choose Tools | Options and locate the template under x*F_XE1#M
* the Source Creation and Management node. Right-click the template and choose jX91=78d
* Open. You can then make changes to the template in the Source Editor. M4}zRr([.5
*/ &uu69)u
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package com.tot.count; At8^yF
import tot.db.DBUtils; #TY[\$BHs
import java.sql.*; d0 yZ9-t
/** [~IFg~*,
* .^?Z3iA",
* @author 1`EkN0iZ
*/ + WFa4NZ
public class CountControl{ @)S d3xw[
private static long lastExecuteTime=0;//上次更新时间 0[SrRpD
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 BQ77n2(@
/** Creates a new instance of CountThread */ tumYZ)nW
public CountControl() {} P;lDri
public synchronized void executeUpdate(){ >]l7AZ:,
Connection conn=null; u=!n9W~"
PreparedStatement ps=null; <o&\/uO~H
try{ $PKUcT0N9
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); uF\f>E)/N%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ %KmhR2v
CountBean cb=(CountBean)CountCache.list.getFirst(); )u_[cEJHO
CountCache.list.removeFirst(); *[wj )
ps.setInt(1, cb.getCountId()); L@LT *M
ps.executeUpdate();⑴ 83YQ c
//ps.addBatch();⑵ V]A*' ke/
} 1ba* U~OEg
//int [] counts = ps.executeBatch();⑶ ?O#,|\v?]
conn.commit(); V']1j
}catch(Exception e){ $3 ~/H"K
e.printStackTrace(); !5h@uar
} finally{ /7XVr"R
try{ u1i
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if(ps!=null) { ++M%PF [
{
ps.clearParameters(); }h`ddo
ps.close(); bjGQ04da
ps=null; _^u^@.Q'i<
} {'eF;!!Dy
}catch(SQLException e){} ]5i]2r1
DBUtils.closeConnection(conn); m^ [VM&%
} S?LUSb
} e.pq6D5
public long getLast(){ i?pC[Ao-_
return lastExecuteTime; Z%O>|ozpq
} .2:S0=xt<
public void run(){ XYsU)(;j
long now = System.currentTimeMillis(); ]h_V5rdX@
if ((now - lastExecuteTime) > executeSep) { 8n)3'ok
//System.out.print("lastExecuteTime:"+lastExecuteTime); Nc[V kJ]
//System.out.print(" now:"+now+"\n"); ` z!?!"=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); _i+7O^=d6X
lastExecuteTime=now; qx\P(dOUf
executeUpdate(); ;tu2}1#r
} ?>o|H-R~5Z
else{ +c_8~C
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [}bPkD
} 7FD.3/
} p*S;4+>#
} Z:s:NvFX
//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 Pi:=0,"XOp
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类写好了,下面是在JSP中如下调用。 |F^h>^
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<% >^hy@m
CountBean cb=new CountBean(); S k&l8"
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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CountCache.add(cb); #^oF^!
out.print(CountCache.list.size()+"<br>"); (qXl=e8
CountControl c=new CountControl(); eMV@er|
c.run(); 8|iMD1
out.print(CountCache.list.size()+"<br>"); sz+Uq]Mn
%>