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: OHp 121
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CountBean.java
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/* afGb}8
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* CountData.java t#6gjfIi
* {B\ar+ 9>
* Created on 2007年1月1日, 下午4:44 Y]B2-wt-
* fCO!M1 t
* To change this template, choose Tools | Options and locate the template under ~?[%uGI0h
* the Source Creation and Management node. Right-click the template and choose 7!Ym~M=
* Open. You can then make changes to the template in the Source Editor. SZK~<@q5
*/ 5c3)p^]g
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package com.tot.count; fo4j^,`
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/** A5!f#
* wKXKc\r
* @author Z fL\3Mn
*/ Co[ rhs
public class CountBean { J@p[v3W
private String countType; xh_6@}D2J
int countId; MFiX8zwhx+
/** Creates a new instance of CountData */ {p
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public CountBean() {} iN<&
public void setCountType(String countTypes){ pWw aN4
this.countType=countTypes; \iSaxwU_
} aoI{<,(
public void setCountId(int countIds){ 7MOjZD4?
this.countId=countIds; >9uDY+70I3
} 6b6}HO
public String getCountType(){ w[~$.FM/
return countType; k8 ,.~HkU
} HGh`O\f8
public int getCountId(){ QVb@/
return countId; F1w~f
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} F4YCU$V
} ~BD VmQa
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CountCache.java jF_K*:gQ
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/* ;ZFn~!V
* CountCache.java t
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* H}dsd=yO
* Created on 2007年1月1日, 下午5:01 Hh$x8ADf
* ^ :6v-
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* To change this template, choose Tools | Options and locate the template under 5d*k[fZ
* the Source Creation and Management node. Right-click the template and choose s'tmak-}|
* Open. You can then make changes to the template in the Source Editor. vp[~%~1(
*/ hGcOk[m 4
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package com.tot.count; =V/$&96Q
import java.util.*; _^0yE_ili
/** YaFQy0t%/5
* D?)"Z$
* @author "m3u}!`3
*/ H9xxId?3u
public class CountCache { &b i Bm
public static LinkedList list=new LinkedList(); n^UrHHOL
/** Creates a new instance of CountCache */ kbI:}b7H
public CountCache() {} <q~&g
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public static void add(CountBean cb){ =L
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if(cb!=null){ ]O,!B''8k
list.add(cb); "qu%$L
} g%4-QCZ,
} I8Y[d$z
} .o]vjNrd/
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CountControl.java V#ZF0a]
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/* $f7#p4;}(
* CountThread.java =SRp
* c#<v:b
* Created on 2007年1月1日, 下午4:57 94 H\,}i8
*
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* To change this template, choose Tools | Options and locate the template under S=U*is
* the Source Creation and Management node. Right-click the template and choose %A,4vLe~6
* Open. You can then make changes to the template in the Source Editor. HH&`f3
*/ R.Ao%VT
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package com.tot.count; R Q X
import tot.db.DBUtils; u `1cXL['
import java.sql.*; f[6;)ZA
/** $A`D p{e"
* 5)wz `OS
* @author t,]r%
*/ .,)NDG4Q
public class CountControl{ +?),BRCce
private static long lastExecuteTime=0;//上次更新时间 fLa 7d?4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 c_s=>z
/** Creates a new instance of CountThread */ ,P3nZ
public CountControl() {} GPy+\P`
public synchronized void executeUpdate(){ AMp[f%X
Connection conn=null; U]riBlg>
PreparedStatement ps=null; fil'._
try{ ^w5`YI4<
conn = DBUtils.getConnection(); zqh.U@
conn.setAutoCommit(false); ow,I|A
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ypM0}pdvTp
for(int i=0;i<CountCache.list.size();i++){ oyZ}JTl(Q
CountBean cb=(CountBean)CountCache.list.getFirst(); $vnshU8/v
CountCache.list.removeFirst(); (]n^_G#-$
ps.setInt(1, cb.getCountId()); 9+)5 #!0
ps.executeUpdate();⑴ _w/w~;7
//ps.addBatch();⑵ .uG|Vq1v
} CvW*/d
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//int [] counts = ps.executeBatch();⑶ J+r\EN^9
conn.commit(); R#.FfWTZ
}catch(Exception e){ PJA%aRP,:
e.printStackTrace(); $TyV<
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} finally{ bnt>j0E
try{ ZT:&j4A|0
if(ps!=null) { ~:~-AXaMT
ps.clearParameters(); g)c<\%
ps.close();
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ps=null; *^e06xc:
} bq#*XCt#
}catch(SQLException e){} G9J+D?'hH
DBUtils.closeConnection(conn); l ?RsXC
} 2{:bv~*I0F
} ~UA:_7#\M
public long getLast(){ ,)^4H>~V
return lastExecuteTime; MwMv[];I
} ejP273*ah
public void run(){ xp<\7m_N
long now = System.currentTimeMillis(); tfW*(oU
if ((now - lastExecuteTime) > executeSep) { {WfZE&B
//System.out.print("lastExecuteTime:"+lastExecuteTime); \6~(#y
//System.out.print(" now:"+now+"\n"); y,e#e`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3m:[o`L
lastExecuteTime=now; r!A1Sfo4P
executeUpdate(); L6S!?t.{Yv
} :%-xiv
else{ Y|$3%t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X&R,-^
} (|H1zO
} F*Lm=^:
} hZ6CiEJB
//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 ?[{_*qh
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类写好了,下面是在JSP中如下调用。 }Fy~DsQ
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<% v53qpqc
CountBean cb=new CountBean(); )1f8
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /sHWJ?`&/,
CountCache.add(cb); gYb}<[O!
out.print(CountCache.list.size()+"<br>"); t*X
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CountControl c=new CountControl(); +*/XfPlr|
c.run(); o ;nw;]oR
out.print(CountCache.list.size()+"<br>"); ,.Xqb~
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