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: kdYl>M
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CountBean.java 4l`gAE$
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/* o"1us75P
* CountData.java #Aan v
* 4COf H7Al9
* Created on 2007年1月1日, 下午4:44 ^&rbI,D
* ;W*$<~_
* To change this template, choose Tools | Options and locate the template under +tN-X'u##
* the Source Creation and Management node. Right-click the template and choose 6HqK%(
* Open. You can then make changes to the template in the Source Editor. 8c|IGC
*/ e #OU {2X
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package com.tot.count; er#=xqUY
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/** t2SZ]|C
* HYH!;
* @author q%vUEQLBp
*/ 5k(#kyP
public class CountBean { 0Yjy
private String countType; 5~X%*_[],
int countId; mHMej@
/** Creates a new instance of CountData */ "}EbA3
public CountBean() {} yN o8R[M
public void setCountType(String countTypes){ >lW*%{|b$^
this.countType=countTypes; z} \9/`
} @&W?e?O ~G
public void setCountId(int countIds){ [Bh]\I'
this.countId=countIds; ]x G4T>S
} o%5bg(
public String getCountType(){ .2P?1HpK
return countType; ybG)=0
} ;~bn@T-
public int getCountId(){ gZUy0`E
return countId; FTfA\/tl(;
} ES2qX]I
} V"ZbKV+[
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CountCache.java ezvaAhd{
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/* K5lp-F
* CountCache.java ]`XuE-Uh
* @^%_ir(
* Created on 2007年1月1日, 下午5:01 k#(cZ
* M::iU_
* To change this template, choose Tools | Options and locate the template under "/fs%F
* the Source Creation and Management node. Right-click the template and choose hI8C XG
* Open. You can then make changes to the template in the Source Editor. j#f&!&G5<&
*/ ,]mwk~HeF
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package com.tot.count; }$1;<
import java.util.*; +_dYfux
/** N0[I2'^.
* c1J)yv1y
* @author o
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*/ He!!oKK>
public class CountCache { ELF`uWGE
public static LinkedList list=new LinkedList(); ek)(pJ(+#
/** Creates a new instance of CountCache */ I uj=d~|>
public CountCache() {} ?ljod6
public static void add(CountBean cb){ *h:EE6|
if(cb!=null){ !nq\x8nU
list.add(cb); c$kb0VR
} 0s""%MhFI
} R?~h7 d
} O)uM&B=
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CountControl.java 5I1J)K;
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/* vGwD~R
* CountThread.java Gc!8v}[7J
* JlQT5k
* Created on 2007年1月1日, 下午4:57 !muYn-4M
* y!N)@y4
* To change this template, choose Tools | Options and locate the template under aSkx#mV
* the Source Creation and Management node. Right-click the template and choose l\;mP.!
* Open. You can then make changes to the template in the Source Editor. aiZo{j<6
*/ Df~p'N-$
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package com.tot.count; u?;Vxh3@|
import tot.db.DBUtils; G+ v, Hi1
import java.sql.*; ` u\z!x'
/** Y\e]2
* prEu9$:t
* @author g~c|~u(W
*/ $l,Zd6<1q
public class CountControl{ `XSc >
private static long lastExecuteTime=0;//上次更新时间 mzE$aFu8
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 n_aNs]C9R
/** Creates a new instance of CountThread */ H<Kkj
public CountControl() {} XyM(@6,'
public synchronized void executeUpdate(){ [s{r$!Gl
Connection conn=null; Sci4EGc
PreparedStatement ps=null; fb"J Bc}X
try{ sh(kRrdY3
conn = DBUtils.getConnection(); Sm$j:xw<
conn.setAutoCommit(false); C8qTz".5$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); M_!u@\
for(int i=0;i<CountCache.list.size();i++){ qE`:b0FT
CountBean cb=(CountBean)CountCache.list.getFirst(); =Esbeb7P
CountCache.list.removeFirst(); ri<'-w i
ps.setInt(1, cb.getCountId()); 9R@abm,I
ps.executeUpdate();⑴ @0ov!9]Rw-
//ps.addBatch();⑵ BLwfm+ m"
} 3aO;@GNJ
//int [] counts = ps.executeBatch();⑶ VXkAFgO
conn.commit(); nEd
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}catch(Exception e){ eMN+qkvH
e.printStackTrace(); ~)wwX:;B_
} finally{ s`#ntset0
try{ r}R^<y@I
if(ps!=null) { u%=bHg
ps.clearParameters(); P(pd0,%i;a
ps.close(); NqT1buU#
ps=null; 3q#"i&
} np-T&Pz2
}catch(SQLException e){} Ehb?CnV#J
DBUtils.closeConnection(conn); t&R!5^R
} <Spr6U9p7
} Lf^5Eo/
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public long getLast(){ 'f-
return lastExecuteTime; wX)efLmyhY
} 0{0;1.ZP
public void run(){ ka2F!
long now = System.currentTimeMillis(); ezcS[r
if ((now - lastExecuteTime) > executeSep) { $R%+*
//System.out.print("lastExecuteTime:"+lastExecuteTime); OgEUq''
//System.out.print(" now:"+now+"\n"); ?CH?kP
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); E\R raPkQT
lastExecuteTime=now; _kn]#^ucCe
executeUpdate(); 20rN,@2<
} "H5&3sF2
else{ n 5~=qQK2
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); hz<|W5
} 7<EJo$-j
} OM20-KDc5
} a?zR8$t|
//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 5R,la\!bQ
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类写好了,下面是在JSP中如下调用。 z@!^ow)`J
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<% <^#P6
CountBean cb=new CountBean(); R'G'&H{N
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @<vF]\Ce
CountCache.add(cb); Z,0O/RFJ.q
out.print(CountCache.list.size()+"<br>"); X,>(Y8
CountControl c=new CountControl(); 5{')GTdX>
c.run(); &bB6}H(
out.print(CountCache.list.size()+"<br>"); $!a?i@
%>