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: F3 wRHq
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CountBean.java )rj.WK.
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/* n1$##=wK]
* CountData.java SxQ|1:i%
* R[#5E|` `9
* Created on 2007年1月1日, 下午4:44 \ iP[iE=
* _NZ)
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* To change this template, choose Tools | Options and locate the template under s"a*S\a;b
* the Source Creation and Management node. Right-click the template and choose 2%WZ-l!i
* Open. You can then make changes to the template in the Source Editor. eKu&_q
*/ iUl{_vb
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package com.tot.count; /$q;-/DnTZ
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/** ;tKL/eI
* W#??fae
* @author kZn!]TseN
*/ }Efp{E
public class CountBean { vTB*J,6.
private String countType; dQizM^j
int countId; bfa5X<8
/** Creates a new instance of CountData */ S
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public CountBean() {} DJ<e=F!
public void setCountType(String countTypes){ kXG+zsT
this.countType=countTypes; ^,`Lt *
} 8q0f#/`v
public void setCountId(int countIds){ I>P</TE7
this.countId=countIds; =z@'vu$Fh
} ";>D0h^D
public String getCountType(){ t_j.@|/FZ
return countType; ;$0za]x
} DR =>la}!
public int getCountId(){ /CZOO)n
return countId; Pu*st=KGB
} t+h"YiT
} J(l6(+8
+)7NWR\
CountCache.java {0QA+[Yd&!
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/* gi"v${R
* CountCache.java 4CN8>J'-
* zu;Yw=cM)
* Created on 2007年1月1日, 下午5:01 +rql7D0st
* B:^U~s R
* To change this template, choose Tools | Options and locate the template under bH,Jddc
* the Source Creation and Management node. Right-click the template and choose Je?V']lm
* Open. You can then make changes to the template in the Source Editor. NgH%
*/ C-2n2OM.
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package com.tot.count; .b]oB_
import java.util.*; bz>#}P=58G
/** 4/d#)6
* 'ugG^2Y
* @author W C`1;(#G
*/ 4Uwt--KtFh
public class CountCache { h@Hmo^!9J
public static LinkedList list=new LinkedList(); C{>?~@z&5
/** Creates a new instance of CountCache */ TbXZU$[c
public CountCache() {} zZE?G:isR
public static void add(CountBean cb){ -R\}Q"
if(cb!=null){ ?2G^6>O`
list.add(cb); !$d:k|b
} 0,/[r/=jT
} {'X "9@
} b,K1EEJ
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CountControl.java -eNi;u
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/* 2.:b
* CountThread.java w]%r]PwU+
* |L+GM"hg
* Created on 2007年1月1日, 下午4:57 &V2G<gm0
* OPjscc5
* To change this template, choose Tools | Options and locate the template under |]B]0J#_
* the Source Creation and Management node. Right-click the template and choose tdt6*
* Open. You can then make changes to the template in the Source Editor. U O[p
*/ C3memimN
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package com.tot.count; %EVg.k$
import tot.db.DBUtils; %?
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import java.sql.*; ,f1+jC
/** Gge"`AT
* xbmOch}j6
* @author CiMN J
*/ <LLSUk/
public class CountControl{ M.l;!U!}
private static long lastExecuteTime=0;//上次更新时间 FEP\5d>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 x t-;7
/** Creates a new instance of CountThread */ 'i@Y #F%D
public CountControl() {} 1`)R#$h
public synchronized void executeUpdate(){ 7*4F-5G/
Connection conn=null; *J$=UG,u
PreparedStatement ps=null; 2s(K4~e e
try{ JEAqSZak#
conn = DBUtils.getConnection(); aH>.o 1;
conn.setAutoCommit(false); ~7Jc;y&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,Wdyg8&.
for(int i=0;i<CountCache.list.size();i++){ ?}Mv5SO
CountBean cb=(CountBean)CountCache.list.getFirst(); oZzE.Q1T
CountCache.list.removeFirst(); BzgDhDj
ps.setInt(1, cb.getCountId()); W:tE ?Hu
ps.executeUpdate();⑴ K1C#
//ps.addBatch();⑵ 9PGSr4V1
} E@N_~1
//int [] counts = ps.executeBatch();⑶ z3$PrK%
conn.commit(); XFX:)l#o
}catch(Exception e){ 6Es-{u(,
e.printStackTrace(); M`5^v0,C
} finally{ +V0uHpm
try{ c8u&ev.U
if(ps!=null) { T[7-3[w<)
ps.clearParameters(); Aimgfxag
ps.close(); mM95BUB
ps=null; V 1Fdt+#
}
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}catch(SQLException e){} t<`BaU
DBUtils.closeConnection(conn); _Fer-nQ2R
} Cx@, J\rsQ
} sNNt0q(
public long getLast(){ k!!o!r BS
return lastExecuteTime; L1 J"_.=P
} T{ojla(
public void run(){ rA_e3L@v#[
long now = System.currentTimeMillis(); K~Xt`
if ((now - lastExecuteTime) > executeSep) { bS0LjvY9g
//System.out.print("lastExecuteTime:"+lastExecuteTime); W"~G]a+
//System.out.print(" now:"+now+"\n"); 8ayB<b>+]"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); rfK%%-
lastExecuteTime=now; gE%- Pf~
executeUpdate(); )!OEa]
} '|6j1i0x
else{ Y pp>7J/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {o;J'yjre1
} f^',J@9@
} qf'uXH
} Hm*n,8_
//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 Gm_Cq2PD(
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类写好了,下面是在JSP中如下调用。 dhV=;'
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<% o^lKM?t
CountBean cb=new CountBean(); F|Ou5WD
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); p>!`JU`{?
CountCache.add(cb); (m@({
out.print(CountCache.list.size()+"<br>"); 6Si z9
CountControl c=new CountControl(); *)"`v]
c.run(); (LGx;9S?
out.print(CountCache.list.size()+"<br>"); "Z#&A
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