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: $`x4|a8-
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CountBean.java )U e9:e
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/* aGx`ec*t
* CountData.java 3J~Q pw0<
* ` *x;&.&v
* Created on 2007年1月1日, 下午4:44 I/rq@27o
* *Ibl+
* To change this template, choose Tools | Options and locate the template under $0V<wsVM
* the Source Creation and Management node. Right-click the template and choose g:`V:kbY$
* Open. You can then make changes to the template in the Source Editor. Wcl@H @
*/ tM <6c+
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package com.tot.count; G+[hE|L~y
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/** E(*RtOC<W
* l_FttN
* @author 3i=+ [
*/ fmY=SqQG-
public class CountBean { p]:5S_$
private String countType; #GT/Q3{C
int countId; u) y6 $
/** Creates a new instance of CountData */ J,%v`A ~N
public CountBean() {} yYwZZa1
public void setCountType(String countTypes){ fB|rW~!v
this.countType=countTypes; cU?A|'
} r ,D
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public void setCountId(int countIds){ 2G<\Wz
this.countId=countIds; =o;8xKj
} &]3_ .C
public String getCountType(){ $(K[W}
return countType; puA~}6C
} h7f&7v
public int getCountId(){ b=horvs/!
return countId; d4t%/ Uh
} }&Ngh4/
} }p$>V,u
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CountCache.java xDG8C39qrs
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/* b/HhGA0
* CountCache.java D/^yAfI
* ZH;VEX
* Created on 2007年1月1日, 下午5:01 kL\
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* S*VG;m#
* To change this template, choose Tools | Options and locate the template under ?%dsY\
* the Source Creation and Management node. Right-click the template and choose ET;YAa*
* Open. You can then make changes to the template in the Source Editor. Xd@ -
*/ <0g.<n,
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package com.tot.count; @{3$H^
import java.util.*; !f[LFQD
/** FJomUVR .
* rg64f'+Eug
* @author Y|FF
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*/ q}p&<k
public class CountCache { #kjN!S*=
public static LinkedList list=new LinkedList(); A-x; ai]
/** Creates a new instance of CountCache */ $OB 2ZS"
public CountCache() {} 1`J-|eH=Q
public static void add(CountBean cb){ XFKe6:
if(cb!=null){ 3cfW|J
list.add(cb); uMKO^D
} :6~Nq/hZB
} I },.U&r
} #pO=\lJ,
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CountControl.java 89o&KF]
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/* &~)PB
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* CountThread.java zrVw l\&
* ,r^zDlS<q
* Created on 2007年1月1日, 下午4:57 KM
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* EK`}?>'
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose ea[vzD]
* Open. You can then make changes to the template in the Source Editor. -d5b,leC^
*/ p)v|t/7
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package com.tot.count; Ey96XJV
import tot.db.DBUtils; F|pM$Kd`
import java.sql.*; ~A^E_
/** " O0p.o
* EZnXS"z
* @author U|SF;T
.
*/ n'*4zxAA
public class CountControl{ 2q]y(kW+
private static long lastExecuteTime=0;//上次更新时间 @
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 U[7 &
/** Creates a new instance of CountThread */ Sv3O${B|
public CountControl() {} w3l2u1u
public synchronized void executeUpdate(){ m#6RJbEz
Connection conn=null; *g7BR`Bt]z
PreparedStatement ps=null; Y\s ge
try{ EMy>X
conn = DBUtils.getConnection(); @'n075)h
conn.setAutoCommit(false); h|~I'M]*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); jMUd,j`Opx
for(int i=0;i<CountCache.list.size();i++){ d8D0 28d
CountBean cb=(CountBean)CountCache.list.getFirst(); "[h9hoN
CountCache.list.removeFirst(); t Sibzl~
ps.setInt(1, cb.getCountId()); "y~tAg
ps.executeUpdate();⑴ fghw\\]3
//ps.addBatch();⑵ )&/ecx"2Q
} oP>+2.i
//int [] counts = ps.executeBatch();⑶ $fifx>!
conn.commit(); 7p1f*N[X
}catch(Exception e){ !UHWCJ<
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e.printStackTrace(); qFQO1"mu
} finally{ bmCp:6
try{ m8[XA!,
if(ps!=null) { xf2|9Tqt
ps.clearParameters(); FgwIOpqE*
ps.close(); $[f-{B{>*
ps=null; 1N\/61+aA
} Cp"a,% b6u
}catch(SQLException e){} WSEw:pln
DBUtils.closeConnection(conn); )+GwYt
} )?`G"(y
} Y#e,NN
public long getLast(){ LH}]& >F
return lastExecuteTime; '#<4oW\]
} kg&R
public void run(){ Ymvd3> _
long now = System.currentTimeMillis(); a+mrsyM
if ((now - lastExecuteTime) > executeSep) { w?#s)z4}g
//System.out.print("lastExecuteTime:"+lastExecuteTime); Cb}I-GtO
//System.out.print(" now:"+now+"\n"); ehTrjb3k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); KC+jHk
lastExecuteTime=now; '
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executeUpdate(); ~fnu;'fN
} N 2XL5<
else{ 4og/y0n,l"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JjMa
} i}Q"'?
} W6c]a/
} njxfBA:
//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 9{*$[%d1
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类写好了,下面是在JSP中如下调用。 0RZ[]:(
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<% VW`SqUl
CountBean cb=new CountBean(); = Ed0vw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); X 0vcBHh
CountCache.add(cb); g1kYL$ o4
out.print(CountCache.list.size()+"<br>"); %T6
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CountControl c=new CountControl(); ,A%p9
c.run(); OLS/3c
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out.print(CountCache.list.size()+"<br>"); X
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%>