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: U N9hZ>9
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CountBean.java tqGrhOt
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/* w>%@Ug["
* CountData.java wh8';LZ>R
* Y %"Ji[
* Created on 2007年1月1日, 下午4:44 j7~FR{:j
* h:?^0b!@
* To change this template, choose Tools | Options and locate the template under U] LDi8
* the Source Creation and Management node. Right-click the template and choose 5'} V`?S
* Open. You can then make changes to the template in the Source Editor. 1F@j?)(
*/ pE5v~~9Ikv
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package com.tot.count; `L'g<VK;
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/** yix[zfQt0
* BX >L7 n
* @author sey,J5?
*/ %k!CjW3
public class CountBean { a`!Jq'
private String countType; = s&Rk~2b/
int countId; xa~]t<2
/** Creates a new instance of CountData */ +hyOc|5
public CountBean() {} mJSfn"b}K
public void setCountType(String countTypes){ c#n
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this.countType=countTypes; }s~c(sL?;
} %fj5;}E.
public void setCountId(int countIds){ 6cH8Jr _
this.countId=countIds; ORExI.<`W
} rW{!8FhI
public String getCountType(){ 0pZvW
return countType; 1R2IlUlzFr
} &9yZfp
public int getCountId(){ QUrPV[JQ
return countId; F$7!j$
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} V(7,N(
} P%3pM*.
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CountCache.java @aIgif+v
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/* }Le]qR9Y]
* CountCache.java U$OZkHA[
* +,76|oMsQ%
* Created on 2007年1月1日, 下午5:01 `b?uQ\#-M
* 7UfNz60+~
* To change this template, choose Tools | Options and locate the template under ZVjB$-do
* the Source Creation and Management node. Right-click the template and choose ;*(-8R/
* Open. You can then make changes to the template in the Source Editor. 7~7L5PRW
*/ QN:v4,$d
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package com.tot.count; w#"\*SKK
import java.util.*; ^tB1Nu%
/** "aJHCi~l
* UL+Txc
* @author &hOz(825r
*/ -%asHDQ{
public class CountCache { p*
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public static LinkedList list=new LinkedList(); QaWS%0go
/** Creates a new instance of CountCache */ 1JJsYX
public CountCache() {}
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public static void add(CountBean cb){ $dL..QH^K
if(cb!=null){ y*
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list.add(cb); yXJhOCa
} W2vL<
} DR#" 3
} 2\xw2VQ@P
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CountControl.java *8}b&4O~
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/* :Jd7q.
* CountThread.java ^6s im 2
* c!6D{(sfh
* Created on 2007年1月1日, 下午4:57 Itl8#LpLM
* n]4E>/\
* To change this template, choose Tools | Options and locate the template under Uj!3MF
* the Source Creation and Management node. Right-click the template and choose o@:"3s
* Open. You can then make changes to the template in the Source Editor. cn'>dz3v
*/ m:H^m/g
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package com.tot.count; 384n1?
import tot.db.DBUtils; Blpk
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import java.sql.*; xTHD_?d
/** yJA~4
* +}:Z9AAMy
* @author :/5m
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*/ }`tSRB7
public class CountControl{ sZ `Tv[
private static long lastExecuteTime=0;//上次更新时间 AxEyXT( h5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &G{GLP?H
/** Creates a new instance of CountThread */ &W<7!U:2m
public CountControl() {} #ArrQeO 5_
public synchronized void executeUpdate(){ T+Oqd\05.+
Connection conn=null; d ^bSV4
PreparedStatement ps=null; HbTVuf o
try{ fM=o?w6v
conn = DBUtils.getConnection(); MxE]EJZ
conn.setAutoCommit(false); D!j/a!MaKk
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); xl}rdnf}
for(int i=0;i<CountCache.list.size();i++){ S=@+qcI
CountBean cb=(CountBean)CountCache.list.getFirst(); cx\"r
CountCache.list.removeFirst(); .;? Bni
ps.setInt(1, cb.getCountId()); 1By tu >2
ps.executeUpdate();⑴ A
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//ps.addBatch();⑵ x YS81
} ~A0]vcP
//int [] counts = ps.executeBatch();⑶ {[y6qQm
conn.commit(); 5!c/J:z
}catch(Exception e){ v">?`8V
e.printStackTrace(); xR+vu>f
} finally{ N`8K1{>BH
try{ ]2AOW}=
if(ps!=null) { @Z5q2Q
ps.clearParameters(); k/K)nH@)
ps.close(); s QDgNJbU
ps=null; 'HA{6v,y
} #6 M]tr
}catch(SQLException e){} 5y#,z`S
DBUtils.closeConnection(conn); M8},RR@{
} )GP;KUVae
} \/
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public long getLast(){ J
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return lastExecuteTime; %cF`x_h[j
} ~D52b1f
public void run(){ P\U<,f
long now = System.currentTimeMillis(); qt8Y3:=8l
if ((now - lastExecuteTime) > executeSep) { >AJ/!{jD*
//System.out.print("lastExecuteTime:"+lastExecuteTime); QkrQM&Im
//System.out.print(" now:"+now+"\n"); 3",gjXmBu
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >* -IIo
lastExecuteTime=now; ni;_Un~
executeUpdate(); K~(RV4oF8B
} DUOoTlp
else{ ~ k*]Z8Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [ 8Ohg
} /!6 'K
} 66=[6U9 *
} %4~"$kE
//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 Jqoo&T")
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类写好了,下面是在JSP中如下调用。 QV|6"4\
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<% DV5hTw0
CountBean cb=new CountBean(); Q'<AV1<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .S` q2C\
CountCache.add(cb); k+QGvgP[4@
out.print(CountCache.list.size()+"<br>"); }">r0v!3
CountControl c=new CountControl(); Ycr3$n]e
c.run(); k!c7eP"%8^
out.print(CountCache.list.size()+"<br>"); ~&?([}A
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