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: :O_<K&
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CountBean.java P St|!GST
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/* ;/]c^y
* CountData.java _{@}Fd?o
* 1OJD\wc
* Created on 2007年1月1日, 下午4:44 \H'CFAuF
* ~wQ WWRk
* To change this template, choose Tools | Options and locate the template under bB[*\
* the Source Creation and Management node. Right-click the template and choose vU=k8
* Open. You can then make changes to the template in the Source Editor. 7dL=E"WL
*/ p>hCh5
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package com.tot.count; )SO1P6
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/** j$/uJ`
* X/C54%T ~
* @author 1pBsr(
*/ 3 %{'Uh,
public class CountBean { %nK15(
private String countType; ?&t|?@
int countId; ) a2m<"
/** Creates a new instance of CountData */ GA*Khqdid
public CountBean() {} & ;x1Rx
public void setCountType(String countTypes){ &|,qsDK(
this.countType=countTypes; OEq e^``!
} 97@?QI}
public void setCountId(int countIds){ QSQ\@h;E
this.countId=countIds; k>@^M]%
} MyS7AL
public String getCountType(){ 'c\TMb.
return countType; mf_9O
} \|4MU"ri
public int getCountId(){ (VF4]
return countId; j~<iTLM
} 4)S?Y"Bs
} x>/@Z6Wxz
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CountCache.java Yka yT0!
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/* 4% .2=
* CountCache.java yeh adm\
* k*+ZLrT
* Created on 2007年1月1日, 下午5:01 G"R>a w
* `x^,k%
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* To change this template, choose Tools | Options and locate the template under 6xQe!d3>s3
* the Source Creation and Management node. Right-click the template and choose fP4IOlHkE
* Open. You can then make changes to the template in the Source Editor. a5g{.:NfO
*/ RwLdV+2\R`
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package com.tot.count; ,lG wW8$R
import java.util.*; ?;kc%Rz
/** =kkA
* 0BZOr-i
* @author #~qp8
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*/ D&lXi~Z%.
public class CountCache { -D':7!@
public static LinkedList list=new LinkedList(); 9fLP&v
/** Creates a new instance of CountCache */ h 7P?n.K
public CountCache() {} +as\>"Cj+2
public static void add(CountBean cb){ fv7g93
if(cb!=null){ Hu!>RSg,,2
list.add(cb); n\NDi22
} xa axj
} 5nw9zW
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} [ESQD5&
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CountControl.java
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/* JA2}
* CountThread.java ^bw~$*"j#
*
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* Created on 2007年1月1日, 下午4:57 ap_+C~%+
* ^ x#RUv
* To change this template, choose Tools | Options and locate the template under KTREOOu .t
* the Source Creation and Management node. Right-click the template and choose S~9kp?kR$
* Open. You can then make changes to the template in the Source Editor. w3hL.Z,kV
*/ G+yz8@
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package com.tot.count; @Bwl)G!|
import tot.db.DBUtils; !a&F:Fbm
import java.sql.*; <%5uzlp
/** 545xs`Q_
* ~}l,H:jk@
* @author `I:,[3_/
*/ +0042Yi
public class CountControl{ LOo#
private static long lastExecuteTime=0;//上次更新时间 WY UU-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 s8O+&^(U
/** Creates a new instance of CountThread */ WkmS
public CountControl() {} :Fk&2WsW:
public synchronized void executeUpdate(){ U}h
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Connection conn=null; yUlQPrNX
PreparedStatement ps=null; r>eXw5Pr7
try{ XfDQx!gJ
conn = DBUtils.getConnection(); <]`2H}*U'
conn.setAutoCommit(false); <GR: 5pJ%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); r+yLK(<zp
for(int i=0;i<CountCache.list.size();i++){ .Cd$=v6
CountBean cb=(CountBean)CountCache.list.getFirst(); HC}C_Q5c91
CountCache.list.removeFirst(); `215Llzk;
ps.setInt(1, cb.getCountId()); yXmp]9$
ps.executeUpdate();⑴ %'<
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//ps.addBatch();⑵ P Qay
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} +u.L6GcB
//int [] counts = ps.executeBatch();⑶ f%l#g ]]
conn.commit(); :
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}catch(Exception e){ FkkB#Jk4
e.printStackTrace();
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} finally{ D(GHkS*0q
try{ 6lFs N2
if(ps!=null) { K 6Ua~N^
ps.clearParameters(); >,1LBM|0u
ps.close(); [K QZHIe
ps=null; T!E LH!
} (]dZ+"O{
}catch(SQLException e){} <H#K `|Ag
DBUtils.closeConnection(conn); 'D{abm0
} k}gs;|_
} 7 4UE-H)
public long getLast(){ XcneH jpR
return lastExecuteTime; );LwWKa
} PUArKBYM-
public void run(){ 1(a\$Di
long now = System.currentTimeMillis(); {S~$\4vC!
if ((now - lastExecuteTime) > executeSep) { Fb-TCq1y#
//System.out.print("lastExecuteTime:"+lastExecuteTime); >iV(8EgBS
//System.out.print(" now:"+now+"\n"); IA!Kpg
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); W5{e.eI}|
lastExecuteTime=now; n&JP/P3Y
executeUpdate(); dy'?@Lj;
} b@Cvs4
else{ 8tk`1E8!j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); HDxw2nz*R
} )I9(WVx!]
} }(6k7{,Gw,
} mer{Jys
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Rl8-a8j$f.
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类写好了,下面是在JSP中如下调用。 Q0q$ZK6C
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<% W=:+f)D
CountBean cb=new CountBean(); } U.B$4Q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); tDVdl^#
CountCache.add(cb); Uk4">]oct
out.print(CountCache.list.size()+"<br>"); 8&bj7w,K
CountControl c=new CountControl(); #U6qM(J
c.run(); ;C%EF
out.print(CountCache.list.size()+"<br>"); 1C{n\_hR
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