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: ?BXP}]
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CountBean.java AW]("pt
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/* s=3EBh
* CountData.java ^?81.b|qb
* #wq;^)>
* Created on 2007年1月1日, 下午4:44 vK[v
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* <x.]OZgO
* To change this template, choose Tools | Options and locate the template under Sj,4=a
* the Source Creation and Management node. Right-click the template and choose eimA *0Cq
* Open. You can then make changes to the template in the Source Editor. U1OLI]P
*/ VGkW3Nt0
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package com.tot.count; W ??;4
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/** 6~>^pkV
* (UbR%A|v;
* @author z{7,.S
u
*/ 9}? 5p]%
public class CountBean { @$K![]oD
private String countType; D>!v_v6
int countId; ]l9,t5Y
/** Creates a new instance of CountData */ btr x?k(
public CountBean() {} ,3g]=f
public void setCountType(String countTypes){ 6x`\
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this.countType=countTypes; n0
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}
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public void setCountId(int countIds){ @k#z&@b
this.countId=countIds; o3(|FN
} &@`H^8
public String getCountType(){
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return countType; r!-L`GUm
} uv_P{%TK
public int getCountId(){ noB}p4
return countId; 1.ugXD
} U)T/.L{0i
} 3XYIb Xnk
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CountCache.java tCF0Ah
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/* e!L sc3@
* CountCache.java Bm2}\KOI
* U:T5o]P<
* Created on 2007年1月1日, 下午5:01 %\s#e
* l[!C-Tq
* To change this template, choose Tools | Options and locate the template under Hme@9(zD.
* the Source Creation and Management node. Right-click the template and choose 7lBQd (
* Open. You can then make changes to the template in the Source Editor. ?><
*/ ix_$Ok
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package com.tot.count; ^LQ lfd
import java.util.*; "KQ\F0/
/** -
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* *+1"S ]YF
* @author Lqf#,J
*/ ]#Z$jq{,
public class CountCache { O(WMTa'%
public static LinkedList list=new LinkedList(); Dv\:b*
/** Creates a new instance of CountCache */ @,f,tk=\S
public CountCache() {} i}&mz~
public static void add(CountBean cb){ DIcyXZH<
if(cb!=null){ 2L{:H
list.add(cb); CI3_lWax%
} Fw8X$SE"
} /hj9Q!
} 2%No>w}/2
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CountControl.java )]e d;V
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/* ?PU(<A+
* CountThread.java `^4>^
* }5c'ui!3H
* Created on 2007年1月1日, 下午4:57 &>^Ympr
* '_yk_[/
* To change this template, choose Tools | Options and locate the template under B0?@k
* the Source Creation and Management node. Right-click the template and choose 1)kl
* Open. You can then make changes to the template in the Source Editor. 9!/1F !
*/ =v#A&IPA'
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package com.tot.count; JbD)}(G;
import tot.db.DBUtils; MxvxY,~{0
import java.sql.*; 1:l&&/Wy
/** [T?6~^m=
* ?+JxQlVDt-
* @author }n&JZ`8<s
*/ Q9'V&jm
public class CountControl{ [q|Q]O0
private static long lastExecuteTime=0;//上次更新时间 ,i((;/O6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8X~vJ^X9@y
/** Creates a new instance of CountThread */ ^xu)~:} i
public CountControl() {} ~$&r(9P
public synchronized void executeUpdate(){ /01(9(
Connection conn=null; dZ81\jdYv
PreparedStatement ps=null; =+#RyV
try{ \kRJUX!s
conn = DBUtils.getConnection(); 5T@'2)BI=
conn.setAutoCommit(false); :s5<AT Q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Ku,A}5-6
for(int i=0;i<CountCache.list.size();i++){ Tqh Rs
CountBean cb=(CountBean)CountCache.list.getFirst(); _EBDv0s
CountCache.list.removeFirst(); -VT?/=Y
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ps.setInt(1, cb.getCountId()); xM"XNT6b
ps.executeUpdate();⑴ jc.Uh9Kc
//ps.addBatch();⑵ YY>Uf1}*9
} Dve5m=
//int [] counts = ps.executeBatch();⑶ p:n^c5
conn.commit(); xI),0db
}catch(Exception e){ ;,hoX6D$
e.printStackTrace(); ,]N%(>ot
} finally{ SPm5tU
try{ #AnSjl
if(ps!=null) { *LQY6=H
ps.clearParameters(); 'r <BaL
ps.close(); u\;dUnr
ps=null; OmuZ0@.
} 5}aC'j\
}catch(SQLException e){} ?{Z0g+B1
DBUtils.closeConnection(conn); H%gD[!^
} -L<Pm(v&
} fmN)~-DV9`
public long getLast(){ -H;y_^2
return lastExecuteTime; I,uu>-
} u(a&x|WY
public void run(){ 8-l Y6M\R\
long now = System.currentTimeMillis(); :QSW^x
if ((now - lastExecuteTime) > executeSep) { ;;H:$lx
//System.out.print("lastExecuteTime:"+lastExecuteTime); *F&&rsb
//System.out.print(" now:"+now+"\n"); a<36`#N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &;3z 1s/
lastExecuteTime=now; "x^bl+_"
executeUpdate(); 7C
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} zQ_[wM-
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); aRP+?}b">
} p~co!d.q/}
} *[YN|
} J8DbAB4X
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 '$^ F.2
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类写好了,下面是在JSP中如下调用。 PFw"ICs
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<% 4!qDG+m
CountBean cb=new CountBean(); 7y7y<`)I5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Qq`\C0RZ
CountCache.add(cb); Oei2,3l,?
out.print(CountCache.list.size()+"<br>"); 8;NO>L/J]i
CountControl c=new CountControl(); c!T{|'?
c.run(); @>j \~<%
out.print(CountCache.list.size()+"<br>"); Q7%#3ML
%>