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: bZwnaM4"F
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CountBean.java IVxWxM*N<
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/* X@A1#z+s0]
* CountData.java %eWqQ3{P]
* ){;02^tX
* Created on 2007年1月1日, 下午4:44 kL*0M<0 (
* qdD)e$XW,
* To change this template, choose Tools | Options and locate the template under JCniN";r[
* the Source Creation and Management node. Right-click the template and choose 9WG{p[
* Open. You can then make changes to the template in the Source Editor. rSXzBi{
*/ (8a#\Y[b
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package com.tot.count; 1 jb/o5n;
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/** ;3'NMk
* J>vMo@
* @author <'U]`Lp
*/ Qx3eLfm
public class CountBean { |bv,2uW z
private String countType; bCv {1]RC2
int countId; E2wz(,@
/** Creates a new instance of CountData */ n$L51#'
public CountBean() {} ;t#]2<d*
public void setCountType(String countTypes){ LJlZ^kh
this.countType=countTypes; aBuoHdg;
} V&{MQWy
public void setCountId(int countIds){ rJyCw+N0
this.countId=countIds; >h~IfZU1
} ]3{0J
public String getCountType(){ :3h{ A`u
return countType; JH,/jR
} RzKb{>
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public int getCountId(){ /u<nLj 1
return countId; z,SYw &S
} C@\{ehG
} W~n.Xeu{C
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CountCache.java 7j<e)"
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/* "8f?h%t
* CountCache.java ;U=q-tb
* OTWkUB{
* Created on 2007年1月1日, 下午5:01 5f'DoT
* alMYk
* To change this template, choose Tools | Options and locate the template under l~s7Ae
* the Source Creation and Management node. Right-click the template and choose lJ;J~>
* Open. You can then make changes to the template in the Source Editor. EV M7Q>
*/ NcS.49
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package com.tot.count; ff?t[GS
import java.util.*; Rg&-0b
/** )}v3q6?_
* R9vT[{!i
* @author )EM7,xMz
*/ +!t}
public class CountCache { }CL"S_>1
public static LinkedList list=new LinkedList(); &jA\hg#9
/** Creates a new instance of CountCache */ *hhmTc#
public CountCache() {} /hW d/H]
public static void add(CountBean cb){ E8\XNG)V4
if(cb!=null){ pE]?x$5U
list.add(cb); ,V]
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} qeL pXe0c
} Ji'(`9F&a
} F'PQqb {
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CountControl.java g:ErZ;[
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/* Nt`b;X&
* CountThread.java S:Q! "U
* ~^I>#Dd
* Created on 2007年1月1日, 下午4:57 : 9!%ZD
* "bQ[CD
* To change this template, choose Tools | Options and locate the template under FjfN3#qlg
* the Source Creation and Management node. Right-click the template and choose 9W7#u}Z
* Open. You can then make changes to the template in the Source Editor. j|fd-<ng
*/ t
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package com.tot.count; Fqq6^um
import tot.db.DBUtils; n^(A=G
import java.sql.*; km5~Gc}
/** qNgd33u1
* %y[1H5)3<
* @author A?!I/|E^;
*/ WKM)*@#,
public class CountControl{ "@3@/I
private static long lastExecuteTime=0;//上次更新时间 .9G<y 4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4R%*Z~
/** Creates a new instance of CountThread */ \YJy#2K
public CountControl() {} t q50fq'
public synchronized void executeUpdate(){ l;X|=eu'
Connection conn=null; ?9MVM~$
PreparedStatement ps=null; Ds8
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try{ sRHA."A!8
conn = DBUtils.getConnection(); 'XOX@UH d
conn.setAutoCommit(false); 8iQ[9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Cr/`keR
for(int i=0;i<CountCache.list.size();i++){ EOKzzX7 S
CountBean cb=(CountBean)CountCache.list.getFirst(); b4 #R!
CountCache.list.removeFirst(); f&@BKx
ps.setInt(1, cb.getCountId()); -<_$m6x"A
ps.executeUpdate();⑴ a~LC+8|JW
//ps.addBatch();⑵ @DAF 6ygs
} <G8w[hs
//int [] counts = ps.executeBatch();⑶ Rf %HIAVE
conn.commit(); hjx)D
}catch(Exception e){ NtGn88='{
e.printStackTrace();
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} finally{ w) ]H ^6
try{ 4 {GU6v)f
if(ps!=null) { >-<8N-@"n
ps.clearParameters(); q6P
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ps.close(); hIv@i\`
ps=null; zzGYiF?
} I8Vb-YeS
}catch(SQLException e){} <3X7T6_:@
DBUtils.closeConnection(conn); Rhzn/\)|
} T5Eseesp
} iX{G]< n
public long getLast(){ 1t[j"CG(o
return lastExecuteTime; :VmHfOO
} kdx
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public void run(){ f3*?MXxb16
long now = System.currentTimeMillis(); K!AAGj`
if ((now - lastExecuteTime) > executeSep) { /(C~~XP)
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7sNw
//System.out.print(" now:"+now+"\n"); 1YxgR}7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H&}ipaDO
lastExecuteTime=now; $K~LM8_CKy
executeUpdate(); oT95^y\9
} E N^Uki`
else{ m(OvD!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); r} _c
} 'Yy&G\S
} { >{B`e`$
} )
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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 p\vMc\
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类写好了,下面是在JSP中如下调用。 ]1-z!B 4K
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<% tCF&OOI4`
CountBean cb=new CountBean(); 0"k|H&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [p r"ZQ]
CountCache.add(cb); [t]X/O3<
out.print(CountCache.list.size()+"<br>"); f2)XP$:
CountControl c=new CountControl(); he3SR@\T
c.run(); `ejUs]SR
out.print(CountCache.list.size()+"<br>"); y?
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