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: oVoTnGNM6
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CountBean.java ,"h$!k"$g
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/* ^Xa-)Pu
* CountData.java jXZKR(L
* J4`08,
* Created on 2007年1月1日, 下午4:44 hJFQ/(
* qf)]!wU9
* To change this template, choose Tools | Options and locate the template under 7:x.08
* the Source Creation and Management node. Right-click the template and choose @D0Ut9)
* Open. You can then make changes to the template in the Source Editor. 14oD^`-t
*/ ,Oxdqx u7
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package com.tot.count; >#!n"i;
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/** ?[XH`c,
* $9W9* WQL
* @author YnJ=&21
*/ = @3Qsd
public class CountBean { e#_xDR:
private String countType; jS R:ltd
int countId; yjN|PqtSV
/** Creates a new instance of CountData */ :IS]|3wD
public CountBean() {} )zen"](cze
public void setCountType(String countTypes){ 5H?`a7q N
this.countType=countTypes; xB
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} [}d
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public void setCountId(int countIds){ 1LcQ*d
this.countId=countIds; SOeL@!_
} kqv>rA3
public String getCountType(){ f@>27&'WV
return countType; W^al`lg+y
} DhkzVp_
public int getCountId(){ zD2Bhta y
return countId; f,PFvT$5e
} }%_x T
} H}JH339
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CountCache.java 9k2HP]8=[{
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/* )SUT+x(DU
* CountCache.java UHweV:(|T
* pD.7ib^
* Created on 2007年1月1日, 下午5:01 F]SexP4:A
* $5cLhi"`
* To change this template, choose Tools | Options and locate the template under 9 `J `(
* the Source Creation and Management node. Right-click the template and choose =^=9z'u"=
* Open. You can then make changes to the template in the Source Editor. 3vmLftZE}
*/ ?$F:S%eH
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package com.tot.count; [*8wv^
import java.util.*; wdoA>a?q
/** }"Y]GH4Y
* ZK3?"|vhC
* @author yIqsZJj
*/ rb&^ ei9B
public class CountCache { <}N0y*m
public static LinkedList list=new LinkedList(); g8!!:fdu
/** Creates a new instance of CountCache */ "uqa~R{
public CountCache() {} |5$9l#e
public static void add(CountBean cb){ )^g}'V=vIr
if(cb!=null){ VLu_SXlo*
list.add(cb); M_$pqVm
} Mz+|~'R
} C6CX{IA]
} BxO2w1G
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CountControl.java ;^O^&<
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/* 6i%LM`8GEk
* CountThread.java fC]+C(*d
* cV)fe`Gg
* Created on 2007年1月1日, 下午4:57
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* !z58,hv
* To change this template, choose Tools | Options and locate the template under 0!_D M^3
* the Source Creation and Management node. Right-click the template and choose U7tT
* Open. You can then make changes to the template in the Source Editor. 8Tv;,a
*/ VH,k EbJ
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package com.tot.count; dq"b_pr;
import tot.db.DBUtils; f![x7D$
import java.sql.*; ~ E>D0o
/** c@5fiRPv!
* ^X"G~#v=q
* @author ;&;coH8`
*/ \qV5mD]"M
public class CountControl{ Nd^9.6,JU
private static long lastExecuteTime=0;//上次更新时间 .I
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 </:f-J%U/
/** Creates a new instance of CountThread */ CHN!o9f
public CountControl() {} ;7tOFsV
public synchronized void executeUpdate(){ 5}e-\:J>B
Connection conn=null; MvL%*("4b
PreparedStatement ps=null; 1fViW^l_
try{ C[n,j#Mvje
conn = DBUtils.getConnection(); p^5B_r:
conn.setAutoCommit(false); ?n\~&n'C
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {nm#aA%,
for(int i=0;i<CountCache.list.size();i++){ =qCVy:RL4
CountBean cb=(CountBean)CountCache.list.getFirst(); s3/->1#i
CountCache.list.removeFirst(); ItC*[
ps.setInt(1, cb.getCountId()); uC 5mxZ
ps.executeUpdate();⑴ *G'zES0x
//ps.addBatch();⑵ ;T-i+_
} W(~G^Xu
//int [] counts = ps.executeBatch();⑶ _+z@Qn?#6h
conn.commit(); *=~
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}catch(Exception e){ *~prI1e(
e.printStackTrace(); f*2V
} finally{ Y]&HU) u
try{ JEU?@J71O
if(ps!=null) { rTDx|pvYx
ps.clearParameters(); >pG]#Z g
ps.close(); qI:}3b;T
ps=null; 1S
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} y 9/27yWB
}catch(SQLException e){} ^^3
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DBUtils.closeConnection(conn); TnPd pynP
} a!Z,~ V8
} \hv*`ukF
public long getLast(){ i. `S0
return lastExecuteTime; /LPSI^l!m
} '#u|RsZ
public void run(){
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long now = System.currentTimeMillis(); 3::DURkjf
if ((now - lastExecuteTime) > executeSep) { 1i2jYDB"
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); Fg5>CppH
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Eq~&d.j
lastExecuteTime=now; amlE5GK;
executeUpdate(); Ks8S^77
} niqi DT/
else{ $LF zpg
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .OXvv _?<
} 1 /7H` O?
} fo4j^,`
} lwQI
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//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 {j ${i
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类写好了,下面是在JSP中如下调用。 Z3~$"V*ZB{
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<% ?J%$;"q
CountBean cb=new CountBean(); !OPa
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [=S@lURzm@
CountCache.add(cb); xwTN\7f>
out.print(CountCache.list.size()+"<br>"); A4Q8^^byY
CountControl c=new CountControl(); h1FM)n[E7
c.run(); `:-{8Vo7
out.print(CountCache.list.size()+"<br>"); qyp"q{k0
%>