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: .<Z7K @
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CountBean.java NrvS/cI!t
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/* ilK8V4k<T)
* CountData.java |PN-,f{ -
* |xzqYu?o
* Created on 2007年1月1日, 下午4:44 +!POKr
* 6,G^iv6H
* To change this template, choose Tools | Options and locate the template under ,Ucb)8a
* the Source Creation and Management node. Right-click the template and choose HZQ I |
* Open. You can then make changes to the template in the Source Editor. }jd[>zk
*/ eEsEW<su
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package com.tot.count; HqgTu`
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/** if5Y!Tx?G
* z@y*
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* @author $#4z>~0
*/ [v-?MS
public class CountBean { 6@2p@eYo
private String countType; }sy3Mrb
int countId; LWbWj ^
/** Creates a new instance of CountData */ MC#bo{Bq3-
public CountBean() {} gb(\c:yg1R
public void setCountType(String countTypes){ v03~=(
this.countType=countTypes; tBBN62^X
} (XqeX(s
public void setCountId(int countIds){ Cu;X{F'H
this.countId=countIds; q1dYiG.-Z
} <O$'3_S"D
public String getCountType(){ l%Sz6
return countType; tzpGKhrk6
} wX 41R]pF
public int getCountId(){ 6X|KKsPzX
return countId; $
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} mKpUEJ<a
} k5-mK{RZ
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CountCache.java qUtVqS
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/* D3.sR\Hxf
* CountCache.java %n}.E304
* oU~V0{7g
* Created on 2007年1月1日, 下午5:01 !+)$;`
* `*oLEXYN
* To change this template, choose Tools | Options and locate the template under n^Z?u9VR
* the Source Creation and Management node. Right-click the template and choose bT{P1nUu
* Open. You can then make changes to the template in the Source Editor. ^J%
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*/ YSrFHVq
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package com.tot.count; xC;$/u%'
import java.util.*; n;rOH[P
/** tW=0AtZl]
* Kg](kP
* @author 95]%j\
*/ R&xD|w8UjM
public class CountCache { Jy|Mfl%d
public static LinkedList list=new LinkedList(); .j&jf^a5
/** Creates a new instance of CountCache */ 2:DpnLU5
public CountCache() {} g"Ii'JZ?
public static void add(CountBean cb){ wFqz.HoB
if(cb!=null){ mOX I"q]p
list.add(cb); b1*6)
} oub4/0tN,~
} D 0n2r
} &tRnI$D
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CountControl.java 8%xtb6#7M
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/* !-MG"\#Wq
* CountThread.java RmNF]"3%
* vY;Lc
* Created on 2007年1月1日, 下午4:57 _^'k_a
* ;%k%AXw
* To change this template, choose Tools | Options and locate the template under Z#J{tXZc
* the Source Creation and Management node. Right-click the template and choose 'xi..
* Open. You can then make changes to the template in the Source Editor. '6WDs]\
*/ rLKDeB
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package com.tot.count; wUV%NZB
import tot.db.DBUtils; LB{a&I LG
import java.sql.*; 8 Zj>|u
/** 6nq.~f2`
* ', &MYm\
* @author !< X_XA
*/ EEo+#
public class CountControl{ .A `:o
private static long lastExecuteTime=0;//上次更新时间 $\K(EBi#G
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 x4( fW\
/** Creates a new instance of CountThread */ & {/u>,
public CountControl() {} <%Rr-,
public synchronized void executeUpdate(){ Fh/C{cX9g
Connection conn=null; # xoFIH
PreparedStatement ps=null; (@#Lk"B
try{ +es6c')
conn = DBUtils.getConnection(); $7bmUQ|
conn.setAutoCommit(false); CKR9APkv
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P<(mH=K
for(int i=0;i<CountCache.list.size();i++){ .z4FuG,R
CountBean cb=(CountBean)CountCache.list.getFirst(); !*ucVv;
CountCache.list.removeFirst(); )I$Mh@F
ps.setInt(1, cb.getCountId()); O0l;Qi
ps.executeUpdate();⑴ ixH7oWH#
//ps.addBatch();⑵ K*}j1A
} W2B=%`sC
//int [] counts = ps.executeBatch();⑶ *Xnq1_K}
conn.commit(); f
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}catch(Exception e){ ^R$dG[Qf
e.printStackTrace(); DtN6.9H2`
} finally{ F>Oh)VL,Ev
try{ ~VGK#'X:
if(ps!=null) { sI'HS+~pU
ps.clearParameters(); 5.E 2fX
ps.close(); $G}Q}f
ps=null; W P&zF$
} "|%fAE
}catch(SQLException e){} E4.IS=4S
DBUtils.closeConnection(conn); +]zP $5_e
} CKur$$B
} O^$Zz<
public long getLast(){ yLX#:
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return lastExecuteTime; .WPqK>79|
} Bx)&MYY}[[
public void run(){ LYFvzw>M
long now = System.currentTimeMillis(); -XyuA:pxx
if ((now - lastExecuteTime) > executeSep) { H}~^,B2;
//System.out.print("lastExecuteTime:"+lastExecuteTime); OE"Bb
//System.out.print(" now:"+now+"\n"); ?!66yn
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `qgJE_GC
lastExecuteTime=now; O gnpzN
executeUpdate(); 7L6M#B[)e5
} ?n+\T'f!
else{ q<8HG_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2fk
} OY#_0p)i
} z~5'p(|@f
} pk4&-iu9
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Jp#cFUa t
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类写好了,下面是在JSP中如下调用。 E=QQZ\w
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<% 5b'S~Qj#r$
CountBean cb=new CountBean(); qsRh ihPX
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Sx"I]N
CountCache.add(cb); d!:SoZ
out.print(CountCache.list.size()+"<br>"); 4{g|$@s(
CountControl c=new CountControl(); qh 3f
c.run(); >KFJ1}b|3
out.print(CountCache.list.size()+"<br>"); "LWuN>
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