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: (l P4D:X
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CountBean.java 0?Wf\7
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/* LLHOWD C(2
* CountData.java ;)]zv\fC
* 4qz{D"M
* Created on 2007年1月1日, 下午4:44 .z>." `
* WAa1H60VkS
* To change this template, choose Tools | Options and locate the template under w@ylRq
* the Source Creation and Management node. Right-click the template and choose f$W}d0(F;
* Open. You can then make changes to the template in the Source Editor. h8-tbHgpb
*/ !>@V#I
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package com.tot.count; WblV`"~e
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/** I64:-P[\
* (@o
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* @author }qdJ8K
*/ E0Y/N?
public class CountBean { 9la~3L_g
private String countType; (dipKs?K
int countId; ,h`D(,?X
/** Creates a new instance of CountData */ t RyGxqiG
public CountBean() {} VdOd:w
public void setCountType(String countTypes){ $q$\GOQ 9
this.countType=countTypes; >~>[}d;glw
} jTgh+j]AP
public void setCountId(int countIds){ n rB27
this.countId=countIds; RF2XJJ
} _r|ytQ)
public String getCountType(){ Xl+a@Ggtq
return countType; BrcXn@tl
} =l'_*B8
public int getCountId(){ 6ch[B`[h,
return countId; QIV~)`;
} $K5s)!
} 9qy 9
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CountCache.java cH-Zj
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/* ']Xx#U N
* CountCache.java p2vUt
* sx^? Iw,N'
* Created on 2007年1月1日, 下午5:01 9S1V!Jp
* 64>[pZF8
* To change this template, choose Tools | Options and locate the template under #=#$b _6*
* the Source Creation and Management node. Right-click the template and choose gpvj'Ri7V
* Open. You can then make changes to the template in the Source Editor. xa0%;nFKe
*/ I3$vw7}5Y
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package com.tot.count; Z_~DTO2Qg
import java.util.*; FEmlC,%
/** +5mkMZ
* CscJy0dB
* @author BmF>IQ`M?
*/ 1O7ss_E
public class CountCache { #R~NR8(z
public static LinkedList list=new LinkedList(); ^ED>{UiNI
/** Creates a new instance of CountCache */ Df3v"iCq}
public CountCache() {} h1o+7
public static void add(CountBean cb){ h#ot)m|I
if(cb!=null){ E+Mdl*
list.add(cb); $rYu4^
} m8^2k2
} =e/4Gs0*
} 0U*"OSpF
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CountControl.java
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/* {*$J&{6V
* CountThread.java HKw:fGt/o^
* F|Ihq^q
* Created on 2007年1月1日, 下午4:57 ZSt
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* B8Zd#.6]
* To change this template, choose Tools | Options and locate the template under v>!}cB/6
* the Source Creation and Management node. Right-click the template and choose ClZyQ=UAD
* Open. You can then make changes to the template in the Source Editor. ppP?1Il`kb
*/ "TJ^Z!
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package com.tot.count; {Dq51
import tot.db.DBUtils; 6l7a9IJ
import java.sql.*; bLF0MVLM
/** v[3sg2.
* i}"JCqo2
* @author D} 3fx[
*/ DP]|}8~L
public class CountControl{ n7uD(cL
private static long lastExecuteTime=0;//上次更新时间 W)hby`k
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Sd6^%YB
/** Creates a new instance of CountThread */ [KJL%u|8/
public CountControl() {} /n:fxdhe
public synchronized void executeUpdate(){ rNC3h"i\
Connection conn=null; R\amcQ
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PreparedStatement ps=null; kl"Cm`b)
try{ )d`$2D&iY
conn = DBUtils.getConnection(); O_Q,!&*6
conn.setAutoCommit(false); iH0c1}<k$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R7E"7"M10
for(int i=0;i<CountCache.list.size();i++){ gNQJ:!
CountBean cb=(CountBean)CountCache.list.getFirst(); }!Lr!eALr
CountCache.list.removeFirst(); h!~yYNQ"
ps.setInt(1, cb.getCountId()); lM,:c.R
ps.executeUpdate();⑴ x&Rp
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//ps.addBatch();⑵
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} ;f~'7RKy!G
//int [] counts = ps.executeBatch();⑶ %TgM-F,8
conn.commit(); iW~f
}catch(Exception e){ vy?YA-
e.printStackTrace(); e5KF ~0`
} finally{ #
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try{ ,_zt?o\
if(ps!=null) { CNYchE,}
ps.clearParameters(); uu.Nq*3
ps.close(); e)"cm;BJ^P
ps=null; &,7(Wab
} m
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}catch(SQLException e){} oX,M;;Yq
DBUtils.closeConnection(conn); i`L66uV
} rnE'gH(V'
} Su #1yw>
public long getLast(){ +-d>Sl (
return lastExecuteTime; RBwV+X[B
} ^yTN(\9
public void run(){ U$bM:d
long now = System.currentTimeMillis(); kzXW<V9
if ((now - lastExecuteTime) > executeSep) { R FiR)G ,
//System.out.print("lastExecuteTime:"+lastExecuteTime); |-D.
//System.out.print(" now:"+now+"\n"); N2J!7uoQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2fB@zF
lastExecuteTime=now; S5TT
executeUpdate(); e?WR={
} /]&1 XT?
else{ (p!AX<=z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -<=<T@,
} wf1DvsJQl
} 5{TF6
} Y;>'~V#R
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 8<!9mgh
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类写好了,下面是在JSP中如下调用。 yr'`~[oSCy
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<% E@KK\m
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CountBean cb=new CountBean(); a mgex$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N0C5FSH
CountCache.add(cb); rfoCYsX'
out.print(CountCache.list.size()+"<br>"); o9>X"5CmX
CountControl c=new CountControl(); 7F\g3^z9`
c.run(); I|H mbTXa
out.print(CountCache.list.size()+"<br>"); i,T{SV
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