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: 6k-
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CountBean.java 2Mo oqJp
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/* Hru~Y}V
* CountData.java (@&+?A"6`
* QRKr2:o{
* Created on 2007年1月1日, 下午4:44 64R~ $km
* ly~tB LH}
* To change this template, choose Tools | Options and locate the template under 1@S(v L3a
* the Source Creation and Management node. Right-click the template and choose NwbX]pDT
* Open. You can then make changes to the template in the Source Editor. r&_bk
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*/ VkJBqRzBOa
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package com.tot.count; f5o##ia7:
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/** .:/[%q{k
* dlJc~|
* @author G~nQR
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*/ KqhE=2,
public class CountBean { i_<GSUTTr/
private String countType; vg;9"A!(
int countId; jH~VjE>
/** Creates a new instance of CountData */ *)u%KYGr
public CountBean() {} RHv|ijYy
public void setCountType(String countTypes){ DT#F?@LG(
this.countType=countTypes; m:x<maP#E
} mP[Z lS~"
public void setCountId(int countIds){ /JbO $A
this.countId=countIds; q)rxv7Iu\
} ]7DS>%mY(
public String getCountType(){ Yx"un4
return countType; ]b'"l
} Bb9/nsbE
public int getCountId(){ #L`'<ge'g*
return countId; P5Is#7udN8
} m4~>n(
} u #Y#,:{
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CountCache.java `*-rz<G
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/* >\4"k4d}
* CountCache.java R8N*. [
* Of.%rpgy
* Created on 2007年1月1日, 下午5:01 bBg=X}9
* 7Q>bJ Ek7
* To change this template, choose Tools | Options and locate the template under /:-Y7M*
* the Source Creation and Management node. Right-click the template and choose 1.IEs:(;
* Open. You can then make changes to the template in the Source Editor. He)vl.
*/ tLSM]Q
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package com.tot.count; y^[?F>wB
import java.util.*; :[d*
/** GMOnp$@H^s
* =" ;G&)H-
* @author 2`P=ekF]
*/ `PS^o#
public class CountCache { v4Mn@e_#c
public static LinkedList list=new LinkedList(); aaRc?b'/
/** Creates a new instance of CountCache */ uRCZGg&V?#
public CountCache() {} 4#Cm5xAt6
public static void add(CountBean cb){ 1WUlBr/k
if(cb!=null){ pKNrEq
list.add(cb); -F`uz,wZ
} /5N`Euw
} p,K!'\
} JDP /vNq
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CountControl.java
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/* ;GV~MH-F
* CountThread.java [5i}C
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* Q/]t$
* Created on 2007年1月1日, 下午4:57 MHPh!
* hp3
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* To change this template, choose Tools | Options and locate the template under hOj(*7__
* the Source Creation and Management node. Right-click the template and choose O/Mx$Q3re
* Open. You can then make changes to the template in the Source Editor. JyDg=%-$2
*/ N:~CN1
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package com.tot.count; fjh,e
import tot.db.DBUtils; nh*hw[Ord
import java.sql.*; <*[D30<
/** ,~*pPhQ8m
* 0dCg/wJx
* @author p-f"4vH
*/ 'n/L1Fn
public class CountControl{ `EWQ>m+
private static long lastExecuteTime=0;//上次更新时间 BFvRU5&Sz
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Pq3m(+gf
/** Creates a new instance of CountThread */ %4^NX@1jV
public CountControl() {} |3P dlIbO
public synchronized void executeUpdate(){ 0P l>k'9
Connection conn=null; 7p_B?r
PreparedStatement ps=null; ^,{ r[}
try{ 3A!Qu$r9
conn = DBUtils.getConnection(); TrR=3_;.7
conn.setAutoCommit(false); cm17hPe`}n
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); e N^6gub
for(int i=0;i<CountCache.list.size();i++){ K9QC$b9(
CountBean cb=(CountBean)CountCache.list.getFirst(); |32uC3?o
CountCache.list.removeFirst(); 2g
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ps.setInt(1, cb.getCountId()); -(JBgM"
ps.executeUpdate();⑴ g27)$0&0
//ps.addBatch();⑵ RYZM_@5$t
} s_
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//int [] counts = ps.executeBatch();⑶ a_(T9pr
conn.commit(); iyTKy+3A
}catch(Exception e){ 'cPE7uNT
e.printStackTrace(); !EOYqD
} finally{ JmF:8Q3H
try{
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if(ps!=null) { wo5fGQJ
ps.clearParameters(); ~nRbb;M
ps.close(); i;fU],aK!
ps=null; nO
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} b^R_8x
}catch(SQLException e){} =4#p|OZP
DBUtils.closeConnection(conn); l5FKw;=K}:
} IiM=Z=2
} 3XcFBFE
public long getLast(){ &~V6g(9
return lastExecuteTime; MuF{STE>->
} X86r`}
public void run(){ ZZrvl4h
long now = System.currentTimeMillis(); ~S~4pK
if ((now - lastExecuteTime) > executeSep) { h
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//System.out.print("lastExecuteTime:"+lastExecuteTime); _g%,/y 9y
//System.out.print(" now:"+now+"\n"); D_M73s!U
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Kb~i9x&
lastExecuteTime=now; #k|f%!-Vo
executeUpdate(); irF+(&q]jh
} FZ5
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else{ ~n;U5hcB
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); O"9Or3w
} Bmv5yc+;
} Y*0j/91
} 6kHuKxY,
//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 hxkwT
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类写好了,下面是在JSP中如下调用。
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<% AHet,N
CountBean cb=new CountBean(); -=GmI1:=$4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); n'83P%x
CountCache.add(cb); `{H!V~42
out.print(CountCache.list.size()+"<br>"); Ntlbn&lc;D
CountControl c=new CountControl(); i|!W;2KL5
c.run(); qlC4&82=Q
out.print(CountCache.list.size()+"<br>"); .o)
%>