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: %S^:5#9
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CountBean.java
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/* I8|"h8\
* CountData.java >
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* +BE_t(%p"
* Created on 2007年1月1日, 下午4:44 n4.\}%=z
* HkY#i;%N
* To change this template, choose Tools | Options and locate the template under i-.AD4
* the Source Creation and Management node. Right-click the template and choose 2b Fr8FUt-
* Open. You can then make changes to the template in the Source Editor. VxE;tJ>1
*/ ~du U& \
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package com.tot.count; 5mZwg(si
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/** TP/bX&bjCy
* {XV'C@B
* @author !_oR/)
*/ (M{>9rk8
public class CountBean { . BX*C
private String countType; TaF;PGjVw
int countId; &8I*N6p:%/
/** Creates a new instance of CountData */ _C19eW'
public CountBean() {} 5W=Jn?y2
public void setCountType(String countTypes){ W$W w/mcl+
this.countType=countTypes; UID`3X
} xrI9t?QaCb
public void setCountId(int countIds){ \ 7IT[<Se
this.countId=countIds; (iIzoEpb8W
} x:h)\%Dg<
public String getCountType(){ =J]M#6N0
return countType; 9W-1P}e,
} oE2VJKs<B
public int getCountId(){ 1H-~+lf
return countId; 4J?\JcGs
} /2MZH
} .v-2A);I
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CountCache.java tI5*0
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/* EVE"F'Ww,_
* CountCache.java (*,R21<%
* e_g&L)
* Created on 2007年1月1日, 下午5:01 ux,eY
* SLp nVD:'1
* To change this template, choose Tools | Options and locate the template under U#<{RqY
* the Source Creation and Management node. Right-click the template and choose F`,Hf Cb\
* Open. You can then make changes to the template in the Source Editor. Nq|y\3]
*/ `?f<hIJoz
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package com.tot.count; p#3G=FV
import java.util.*; f1?%p)C
/** F?ps?
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* T_#8i^;D
* @author S~&9DQNj
*/ >/NegJh'F}
public class CountCache { t~BWN
public static LinkedList list=new LinkedList(); vsQvJDna~
/** Creates a new instance of CountCache */ _>r(T4}]
public CountCache() {} jhBfy|Ftu
public static void add(CountBean cb){ *pAB dP+
if(cb!=null){ Z`|\%D%
list.add(cb); (cV1Pmn
} -Owb@Nw
} P#
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} lHHx D
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CountControl.java N/<c;"o
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/* :nfy=*M#
* CountThread.java ~yV?*"Hi
* 1=ZQRJW0B
* Created on 2007年1月1日, 下午4:57 k_?~@G[I
* `tcX[(`
* To change this template, choose Tools | Options and locate the template under ]24]id
* the Source Creation and Management node. Right-click the template and choose F+j"bhe
* Open. You can then make changes to the template in the Source Editor. B~J63Os/
*/ 7|"$YV'DM
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package com.tot.count; L$@+'Qn@:
import tot.db.DBUtils; )@!T_#
import java.sql.*; J3B+WD]
/** 1]vDM&9
* ?_v_*+b_
* @author $ f||!g
*/ f9+6gY
public class CountControl{ S,f#g?V
private static long lastExecuteTime=0;//上次更新时间 woF{O)~X
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )J2UNIgN
/** Creates a new instance of CountThread */ 1/6}E]-F
public CountControl() {} DF-.|-^9I
public synchronized void executeUpdate(){ B}K<L\S
Connection conn=null; J,s:CBCGL
PreparedStatement ps=null; FMzG6nrdBN
try{ " BLJh)i
conn = DBUtils.getConnection(); NbCIL8f]
conn.setAutoCommit(false); KT AQ6k
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2 zG;91^
for(int i=0;i<CountCache.list.size();i++){ fu-,<m{
CountBean cb=(CountBean)CountCache.list.getFirst(); K4I/a#S'@6
CountCache.list.removeFirst(); 2L51H(
ps.setInt(1, cb.getCountId()); I1s$\NZ~]
ps.executeUpdate();⑴ yS3or(K
//ps.addBatch();⑵ #\O'*mz
} h##U=`x3
//int [] counts = ps.executeBatch();⑶ n</Rd=
conn.commit(); =}Q|#C
}catch(Exception e){ =Lnip<t>ja
e.printStackTrace(); sM%l:Fv
} finally{ 7Jz9%iP
try{ 2 gca*
if(ps!=null) { DbtkWq%
ps.clearParameters(); j0 w@ \gO<
ps.close(); KuL+~
ps=null; mX?t|:[b
} OKk"S_`
}catch(SQLException e){} x5rLGt
DBUtils.closeConnection(conn); Lf%}\0:
} -8dz`o}
} ml!c0<
public long getLast(){ ZCMH?>
return lastExecuteTime; 6z:/ma^
} @xBO[v
public void run(){ fvV"H{V,
long now = System.currentTimeMillis(); %|>D{q6C
if ((now - lastExecuteTime) > executeSep) { Q
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//System.out.print("lastExecuteTime:"+lastExecuteTime); 6#\:J0
//System.out.print(" now:"+now+"\n"); 9}tl@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3\C+g{}e
lastExecuteTime=now; 2!9Zw$
executeUpdate(); w@n}DCFt
} eZ0-O /_i
else{ EB6X
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7@m+y
} _A0X[}^K
} nE2?3 S>
} BN&}g}N
//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 |ZXz&Xor
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类写好了,下面是在JSP中如下调用。 !\O!Du
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<% 7KJ0>0~Et
CountBean cb=new CountBean(); Kb1@ +
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); r:4]:NKCi
CountCache.add(cb); ]KG.-o30
out.print(CountCache.list.size()+"<br>"); h~z}NP
CountControl c=new CountControl(); u0g"x_3
c.run(); dJdOh#8+Xi
out.print(CountCache.list.size()+"<br>"); yNU}1_oK
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