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: mCtS_"W
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CountBean.java h`fVQN.3
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/* DT1gy:?L
* CountData.java x%P|T3Qy5
* "(koR Q
* Created on 2007年1月1日, 下午4:44 Gn]36~)*H
* .p`4>XA
* To change this template, choose Tools | Options and locate the template under g8),$:Uw
* the Source Creation and Management node. Right-click the template and choose )^h6'h`
* Open. You can then make changes to the template in the Source Editor. cH]tZ$E`
*/ dn6B43w
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package com.tot.count; W+XWS,(
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/** zd?@xno
* j jpYg
* @author *OVB;]D3+
*/ 6 Z/`p~e
public class CountBean { ;`9f<d#\
private String countType; N!A20Bv
int countId; y!e]bvN
/** Creates a new instance of CountData */ }fpya2Xt
public CountBean() {} fGgt[f[
public void setCountType(String countTypes){ ;?6vKpj;
this.countType=countTypes; A=CeeC]}
} L\yVE
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public void setCountId(int countIds){ y>{:[L9*
this.countId=countIds; :fRXLe1=
} mp|pz%U
public String getCountType(){ -@uFRQt
return countType; b^Hrzn
}
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public int getCountId(){ QbU5FPiN
return countId; ^S#;
} yTaMlT|
} -H1=N
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CountCache.java oL4W>b )
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/* |J`EM7qMK
* CountCache.java TyxIlI4"
* :-&|QVH
* Created on 2007年1月1日, 下午5:01 -"(*'hD
* r^9l/H~$
* To change this template, choose Tools | Options and locate the template under 4.6$m
* the Source Creation and Management node. Right-click the template and choose <sdgL+&1h
* Open. You can then make changes to the template in the Source Editor. &9k~\;x
*/ urp|@WZ
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package com.tot.count; c,UJ uCZ
import java.util.*; ?0b-fL^^+l
/** 95 ;{ms[
* [ X*p
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* @author Re%[t9F&
*/ -luQbGcT3
public class CountCache { ia6 jiW x
public static LinkedList list=new LinkedList(); , ,3lH-C
/** Creates a new instance of CountCache */ PN}+LOD<t
public CountCache() {} #mH@ /6,#[
public static void add(CountBean cb){ :,BAw ,
if(cb!=null){ 5Iu5N0cn
list.add(cb); bT,:eA
} |@ mz@
} _sjS'*]
} |%_C$s%
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CountControl.java Z:b?^u4.
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/* 3CUQQ_
* CountThread.java I-v}
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* 3F9V,zWtTi
* Created on 2007年1月1日, 下午4:57 6)HmE[[F
* D)*
* To change this template, choose Tools | Options and locate the template under O5dS$[`j\p
* the Source Creation and Management node. Right-click the template and choose <H[w0Z$
* Open. You can then make changes to the template in the Source Editor. \u=d`}E
*/ `At.$3B
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package com.tot.count; vz^ ] g
import tot.db.DBUtils; %wD#[<BGn>
import java.sql.*; yCX5
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/**
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* 37bMe@W
* @author Iil2R}1
*/ WR+j?Fcf
public class CountControl{ !0
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private static long lastExecuteTime=0;//上次更新时间 d[9,J?'OQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 s"L&y <?)
/** Creates a new instance of CountThread */ .Xg.,kW
public CountControl() {} >OG189O
public synchronized void executeUpdate(){ z%&FLdXgW+
Connection conn=null; o$_0Qs$
PreparedStatement ps=null; GT>'|~e
try{ <J%qzt}
conn = DBUtils.getConnection(); T/$gnn
conn.setAutoCommit(false); w+$$uz
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); i Ad&o`C
for(int i=0;i<CountCache.list.size();i++){ 2w>%-_]u+
CountBean cb=(CountBean)CountCache.list.getFirst(); W 4{ T<
CountCache.list.removeFirst(); ET*A0rt
ps.setInt(1, cb.getCountId()); YV>a 3
ps.executeUpdate();⑴ FT).$h~+4
//ps.addBatch();⑵ iIfiv<(ChM
} IPot][ N>
//int [] counts = ps.executeBatch();⑶ +Z#=z,.^
conn.commit(); K5>3
}catch(Exception e){ eAHY/Y!
e.printStackTrace(); o.s'0xP]
} finally{ (6,:X
try{ AvL /gt:
if(ps!=null) { %$BRQ-O
ps.clearParameters(); 7uBx
ps.close(); j
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ps=null; K'OG-fn;
} 8lQ/cGAc
}catch(SQLException e){} hzD)yf
DBUtils.closeConnection(conn); a %go[_w
} B'/U#>/
} |N,^*xP(6
public long getLast(){ 4+olyBht
return lastExecuteTime; pEB3qGA
} 8X;?fjl`"
public void run(){ !~^2Mu(X
long now = System.currentTimeMillis(); g |)>65v
if ((now - lastExecuteTime) > executeSep) { gx\V)8Zr
//System.out.print("lastExecuteTime:"+lastExecuteTime); "|\hTRQ
//System.out.print(" now:"+now+"\n"); +U
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); UMcM&yu-
lastExecuteTime=now; 3 s\UU2yr
executeUpdate(); ]0i[=
} L03I:IJ
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Aez2n(yac
} vuQA-w7
} hB?#b`i^
} ;NP-tA)
//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 0jp].''RK\
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类写好了,下面是在JSP中如下调用。 l&& i`
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<% >^8O :.
CountBean cb=new CountBean(); kV-<[5AWW
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Z<U,]iZB
CountCache.add(cb); 8~ y!X0Ov!
out.print(CountCache.list.size()+"<br>"); 6Ga'_P:
CountControl c=new CountControl(); lw=kTYbq
c.run(); LcKc#)'EE
out.print(CountCache.list.size()+"<br>"); g}9,U&$]y
%>