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: 9&`";dg
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CountBean.java ~UNha/nt
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/* )|k#cT{=M
* CountData.java 3]9Rmx
* yG7H>LF?8
* Created on 2007年1月1日, 下午4:44 [6_.Y*}N
* dC-~=}HR^
* To change this template, choose Tools | Options and locate the template under 4#]g852
* the Source Creation and Management node. Right-click the template and choose 1@h8.ym<"
* Open. You can then make changes to the template in the Source Editor. .y3E@0a
*/ A*81}P_
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package com.tot.count; #=33TvprR2
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/** jWi~Q o+
* |O oczYf
* @author WWZ<[[ >
*/ o$+R
public class CountBean { T6=|)UTe1
private String countType; g}gGm[1SUo
int countId; cg17e
/** Creates a new instance of CountData */ ?b{y#du2a
public CountBean() {} d,(q3
public void setCountType(String countTypes){ _X;,,VEV!
this.countType=countTypes; SG|AJ9
} =N{?ll6x7g
public void setCountId(int countIds){ fHEIys,{
this.countId=countIds; yUpN`;
} X';qcn_^
public String getCountType(){ Us'JMZ~
return countType; xR&:]M[Vg
} A46q`l9B
public int getCountId(){ 3C%|src
return countId; 3'` &D/n
} ht ]n*
} ?hc=w 2Ci
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CountCache.java .d^8?vo
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/* ^\Q,ACkZb
* CountCache.java QK0]9
* y] D\i5Xv
* Created on 2007年1月1日, 下午5:01 wzwv>@}
* XE<5(
* To change this template, choose Tools | Options and locate the template under Dbj?l;'1
* the Source Creation and Management node. Right-click the template and choose ||pOiR5
* Open. You can then make changes to the template in the Source Editor. )z@
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*/ U2<q dknB
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package com.tot.count; ov,
import java.util.*; ~qL/P 5*+
/** :si&A;k
* UHfE.mTjM
* @author G;/>
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*/ +[i r7?Y.
public class CountCache { 5HbJE'
public static LinkedList list=new LinkedList(); A`(Cuw-o
/** Creates a new instance of CountCache */ oGeV!hD
public CountCache() {} 9w&CHg7D
i
public static void add(CountBean cb){ }>,%El/
if(cb!=null){ 7bGt'gvv
list.add(cb); bqF?!t<B
} (C`nBiL<
} %t9Kc9u3p
} +",`Mb
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CountControl.java 9"B;o
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/* lQ[JA[
* CountThread.java K'"s9b8
* Mjl,/-0 w
* Created on 2007年1月1日, 下午4:57 qnd] UUA^
* "<&o;x<
* To change this template, choose Tools | Options and locate the template under n@C#,v#^0
* the Source Creation and Management node. Right-click the template and choose 1UrkDz?X
* Open. You can then make changes to the template in the Source Editor. 91a);d
*/ f<<$!]\
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package com.tot.count; f::^zAV
import tot.db.DBUtils; T2|<YJ=
import java.sql.*; $'#}f?
/** :=q9ay
* B<@a&QBTg
* @author wc}x
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*/ 0f+]I=1\
public class CountControl{ ,gkWksl9
private static long lastExecuteTime=0;//上次更新时间 Qd?S~3XT
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %.uN|o&n
/** Creates a new instance of CountThread */ I;$tBgOWq
public CountControl() {} GV9pet89yu
public synchronized void executeUpdate(){ >A6PH*x
Connection conn=null; VWCC(YRU|$
PreparedStatement ps=null; 7
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try{ q}g0-Da
conn = DBUtils.getConnection(); VF7H0XR/k5
conn.setAutoCommit(false); wmP[\^c%$j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `"iPJw14
for(int i=0;i<CountCache.list.size();i++){ aH500
CountBean cb=(CountBean)CountCache.list.getFirst(); LzB*d
CountCache.list.removeFirst(); jM'Fb.>~
ps.setInt(1, cb.getCountId()); D2:ShyYAS
ps.executeUpdate();⑴ k5)IBO
//ps.addBatch();⑵ 3VQmo\li
} oye/tEMG
//int [] counts = ps.executeBatch();⑶ d;r,?/C
conn.commit(); Z\)P|#L$
}catch(Exception e){ yW"}%)
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e.printStackTrace(); _B}QS"A
} finally{ oJ=u
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try{ diw5h};W
if(ps!=null) { GL&rT&
ps.clearParameters(); p1ER<_fp
ps.close(); o3OJI_
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ps=null; W;,RU8\f
} w;Pe_m7\EO
}catch(SQLException e){} `-rtU
DBUtils.closeConnection(conn); H[r6 4~Sth
} $T2zs$
} I=K<%.
public long getLast(){ MY&?*pV)
return lastExecuteTime; V5I xZn%
} iW?NxP
public void run(){ JQ\o[t
long now = System.currentTimeMillis(); 2
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if ((now - lastExecuteTime) > executeSep) { @c,=c+-
//System.out.print("lastExecuteTime:"+lastExecuteTime); @oMl^UYM=
//System.out.print(" now:"+now+"\n"); mj2sbRiSR=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; q1%xk=8
executeUpdate(); Sa6YqOel@
} X=JAyxY
else{ KH[Oqd
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); J8`vk#5
} f%STkL)
} IS!]!s'EI
} Lb2/ Te*
//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 *>j4tA{b@v
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类写好了,下面是在JSP中如下调用。 @ v}M\$N?
T!5g:;~y >
<% .lppT)P
CountBean cb=new CountBean(); !AL?bW
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _3_o/I
CountCache.add(cb); (Z>vbi%
out.print(CountCache.list.size()+"<br>"); !z?:Y#P3
CountControl c=new CountControl(); ZpU4"x>
c.run(); ?eR^\-e
out.print(CountCache.list.size()+"<br>"); `&A-m8X
%>