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: b&pL}o?/k
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CountBean.java ~@D!E/hZx
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/* Y3'dV)
* CountData.java oYeFOw`
* lJ4/bL2I/
* Created on 2007年1月1日, 下午4:44 lstnxi%x
* >LEp EMJ\
* To change this template, choose Tools | Options and locate the template under S?~/
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* the Source Creation and Management node. Right-click the template and choose 7{f{SIB
* Open. You can then make changes to the template in the Source Editor. (*!4O>]
*/ r`:dUCFE
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package com.tot.count; DJR r
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/** 6wyhL-{:
* 42DB0+_wz
* @author ob(~4H-
*/ k@2@%02o9C
public class CountBean { ]5eZLXM
private String countType; yfe4}0}
int countId; [>kzQYT[
/** Creates a new instance of CountData */ Yb>A?@S
public CountBean() {} bLz('mUY
public void setCountType(String countTypes){ v,c:cKj
this.countType=countTypes; `%0k\,}V
} 8uetv
public void setCountId(int countIds){ ,aSK L1
this.countId=countIds; >vQKCc|93
} lMXLd91
public String getCountType(){ QPsvc6ds
return countType; k=5v
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} t$U eks
public int getCountId(){ l`AA<Rj*O-
return countId; Be0v&Q_NK
} |DoD.?v
} ,#80`&\%
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CountCache.java Pill |4 c<
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/* LGC3"z\=
* CountCache.java AjO|@6
* &uu69)u
* Created on 2007年1月1日, 下午5:01 f1/if:~6
* At8^yF
* To change this template, choose Tools | Options and locate the template under 6b=7{nLF
* the Source Creation and Management node. Right-click the template and choose >zcp(M98
* Open. You can then make changes to the template in the Source Editor. ,6^V)F
*/ ]4-t*Em
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package com.tot.count; )%(H'omvl
import java.util.*; TZ@S?r>^
/** uB3Yl=P
* @>hXh
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* @author >U[YSsFt6
*/ je~gk6}Y
public class CountCache { VxGR[kq$]
public static LinkedList list=new LinkedList(); =:v5`
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/** Creates a new instance of CountCache */ gS^Y?
public CountCache() {} \>|:URnD
public static void add(CountBean cb){ C Z/:(sOJ
if(cb!=null){ fhQ}Z%$
list.add(cb); ?N!.:~~k
} ;!/g`*?
} >U'gQS?\]
} L@LT *M
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CountControl.java U~[ tp1Z)
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/* zRF+D+
* CountThread.java $8Y|&P
* wg 6
* Created on 2007年1月1日, 下午4:57 -Mufo.Jz1o
* a6.0$'
* To change this template, choose Tools | Options and locate the template under ^>!~%Vv7!
* the Source Creation and Management node. Right-click the template and choose &$E.rgtg
* Open. You can then make changes to the template in the Source Editor. )u(Dq u\t
*/ bmGtYv
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package com.tot.count; 8AVG pL
import tot.db.DBUtils; :l?/]K
import java.sql.*; 5Lm<3:7Q+
/** 3r,^is
* @
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* @author 91j.%#[v'
*/ t_ZWd#x+;
public class CountControl{ RkXW(T`
private static long lastExecuteTime=0;//上次更新时间 [^E{Yz=8,
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `?xE-S
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/** Creates a new instance of CountThread */ 8&KqrA86
public CountControl() {} 8n)3'ok
public synchronized void executeUpdate(){ Nc[V kJ]
Connection conn=null; ` z!?!"=
PreparedStatement ps=null; _i+7O^=d6X
try{ qx\P(dOUf
conn = DBUtils.getConnection(); ;tu2}1#r
conn.setAutoCommit(false); lC(g&(\{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +c_8~C
for(int i=0;i<CountCache.list.size();i++){ B< BS>(Nr>
CountBean cb=(CountBean)CountCache.list.getFirst(); >4eZ%</D5
CountCache.list.removeFirst(); R?GF,s<j
ps.setInt(1, cb.getCountId()); : yC|Q)
ps.executeUpdate();⑴ WL/9r
*jW
//ps.addBatch();⑵ "f<+~
} j*}2AI
//int [] counts = ps.executeBatch();⑶ "jG-)k`a
conn.commit(); ,}_uk]AQ
}catch(Exception e){ \Z ms
e.printStackTrace(); #mcU);s
} finally{ Kf-rthO
try{ AT]Ty
if(ps!=null) { JPfE`NZ
ps.clearParameters(); 9J'3b <
ps.close(); h9L/.>CX
ps=null; >n^[-SWJCT
} X-=J7G`\h#
}catch(SQLException e){} 1(12`3
DBUtils.closeConnection(conn); ;Q} H'Wg,
} 4Gm (P~N
} N:Zf4
public long getLast(){ gR:21*&cz
return lastExecuteTime; |Zrkk>GW:
} R~&i8n.
public void run(){ -6u#:pVpU
long now = System.currentTimeMillis(); qo" _w%{
if ((now - lastExecuteTime) > executeSep) { z("Fy
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0al8%z9e@
//System.out.print(" now:"+now+"\n"); GcYT<pwN6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :Y ;\1J<b1
lastExecuteTime=now; 6$^dOJ_"
executeUpdate(); H0 .,h;
} }8cX0mZ1j
else{ $1$T2'C~+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;BMm47<
} rCa2$#Z
} z7P]g
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} =q-HR+
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Rr>h8Ni <
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类写好了,下面是在JSP中如下调用。 Du2v,n5@
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<% P?P))UB5
CountBean cb=new CountBean(); Ho:X.Z9A^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !1\jD
CountCache.add(cb); T{%'"mm;
out.print(CountCache.list.size()+"<br>"); d(-$ {
c
CountControl c=new CountControl(); |6.1uRF E2
c.run(); :'LG%E:b
out.print(CountCache.list.size()+"<br>"); =wy 3h0k^
%>