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: rr#nBhh8
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CountBean.java 0 C4eer+D
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/*
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* CountData.java U[C>Aoze
* 5|*{~O|
* Created on 2007年1月1日, 下午4:44 %
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* -K|1w'E
* To change this template, choose Tools | Options and locate the template under MQ,K%_m8
* the Source Creation and Management node. Right-click the template and choose IQ&PPC
* Open. You can then make changes to the template in the Source Editor. WNR]GI
*/ Vr2A7kq
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package com.tot.count;
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/** "FHJ_$!
* Q,?_;,I}
* @author xG!~TQ
*/ ^ ` LqNG
public class CountBean { h<9vm[ .
private String countType; 7FH(C`uKi
int countId; _k:8ib2TQ
/** Creates a new instance of CountData */ !}Xoqamm
public CountBean() {} 8}n<3_
public void setCountType(String countTypes){ 0zW*JJxV
this.countType=countTypes; |5u~L#P
} KL \>-
public void setCountId(int countIds){ rLTBBvV
this.countId=countIds; \$ 9C1@B@
} 2 "&GH1
public String getCountType(){ 7@@g|l]
return countType; gvP-doA7W
} N~/'EaO
public int getCountId(){ =3-=p&*
return countId; 3IYFvq~
} ^E}?YgNp
} h,/Aq
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CountCache.java =lAjQt
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/* L{/%
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* CountCache.java O Z
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* eT
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* Created on 2007年1月1日, 下午5:01 Pmv@
* BX/3{5Y>{
* To change this template, choose Tools | Options and locate the template under nDnJ}`k
* the Source Creation and Management node. Right-click the template and choose luP;P&
* Open. You can then make changes to the template in the Source Editor. uV:R3#^
*/ IiE6i43
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package com.tot.count; $;5Q
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import java.util.*; tW/k
/** EE9w^.3a
* V$ZclV2:Ih
* @author N.*)-O
*/ Kq[4I[+R
public class CountCache { 5 `1
public static LinkedList list=new LinkedList(); gnJ8tuS
/** Creates a new instance of CountCache */ a0NiVF-m%
public CountCache() {} jG>W+lq
public static void add(CountBean cb){ 9#9 UzKX#
if(cb!=null){ 8-#kY}d.
list.add(cb); 3ijPm<wn
} !hVbx#bXl
} DS?.'"n[u
} Pn!~U] A$%
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CountControl.java MpOU>\
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/* N
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* CountThread.java g8O6
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* W
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* Created on 2007年1月1日, 下午4:57 <,CrE5Pl
* U:8[%a
* To change this template, choose Tools | Options and locate the template under t7by OMC
* the Source Creation and Management node. Right-click the template and choose G*z\
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* Open. You can then make changes to the template in the Source Editor. 'K4FS(q
*/ hywcj\[
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package com.tot.count; xM%4/QE+
import tot.db.DBUtils; tp`1S+'~j
import java.sql.*; ROFZ*@CH<
/** .D@J\<,+l
* q-! H7o
* @author >'4A[$$4mM
*/ Ki><~!L
public class CountControl{ ]5'$EAsuW
private static long lastExecuteTime=0;//上次更新时间 8 m"k3:e^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3(c-o0M
/** Creates a new instance of CountThread */ (;#c[eKy
public CountControl() {} 8>YF}\D V
public synchronized void executeUpdate(){ 1<ag=D`F_"
Connection conn=null; )-
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PreparedStatement ps=null; zT>!xGTu7~
try{ AW5iwq6p
conn = DBUtils.getConnection(); ET.jjV
conn.setAutoCommit(false); c)#P}Ai
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); l5-[a
for(int i=0;i<CountCache.list.size();i++){ !<M
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CountBean cb=(CountBean)CountCache.list.getFirst(); )JzY%a SP
CountCache.list.removeFirst(); uzdPA'u
ps.setInt(1, cb.getCountId()); oPi>]#X
ps.executeUpdate();⑴ 1Ms]\<^j
//ps.addBatch();⑵ g-qXS]y7
} CM?:\$ 4
//int [] counts = ps.executeBatch();⑶ i}vJI}S.$
conn.commit(); f\_RW;y|m
}catch(Exception e){ B@F@,?K4%
e.printStackTrace(); FJeh=\
} finally{ 9JFN8Gf*)
try{ m?kiGC&m
if(ps!=null) { ! AwMD
ps.clearParameters(); uG\~Hxqw7O
ps.close(); *I 1 H
ps=null; X%b1KG|#(
} %mC@}
}catch(SQLException e){} ny{C,1QG
DBUtils.closeConnection(conn); Om*QN]lGq
} $e+sqgU
} ILm+o$o~
public long getLast(){ Vg'R=+Wb
return lastExecuteTime; 7Bj,{9^aJ
} MhN;GMH
public void run(){ -,")GA+[7
long now = System.currentTimeMillis(); t^'nh
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if ((now - lastExecuteTime) > executeSep) { E !!,JnU
//System.out.print("lastExecuteTime:"+lastExecuteTime); `/sNX<mp
//System.out.print(" now:"+now+"\n"); &D3]O9a0;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); cUq]PC$|
lastExecuteTime=now; P3"R2-
executeUpdate(); @bg9
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} !@& 3q|
else{ h~>1-T8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }StzhV{GS
} akvi^]x
} m]jA(
} EL~$7 J
//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 IWE([<i}i[
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类写好了,下面是在JSP中如下调用。 rDFrreQP
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<% aMI;;iL^
CountBean cb=new CountBean(); +RJ{)Nec
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0%bCP/
CountCache.add(cb); NQqw|3
out.print(CountCache.list.size()+"<br>"); l>\EkUT
CountControl c=new CountControl(); ^BF}wQb:j
c.run(); &ZD@-"@
out.print(CountCache.list.size()+"<br>"); ]r;rAOWVV
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