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: {|7OmslC@
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CountBean.java 0,"n-5Im
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/* OTNZ!U/)j
* CountData.java d
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* I9Edw]
* Created on 2007年1月1日, 下午4:44 #um1?V
* 8zWBXV
* To change this template, choose Tools | Options and locate the template under #LrCx"_&
* the Source Creation and Management node. Right-click the template and choose @>
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* Open. You can then make changes to the template in the Source Editor. ||*&g2Y
*/ EE{#S
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package com.tot.count; @y;tk$e
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/** ,,wyydG
* lo>-}xd
* @author l b1sV
*/ =JySY@?9
public class CountBean { !Wdt:MUI8
private String countType; @6I[{{>X
int countId; "PDSqYA
/** Creates a new instance of CountData */ sGDrMAQt
public CountBean() {} a dz;N;rIY
public void setCountType(String countTypes){ "z(fBnv
this.countType=countTypes; !w;A=
} F|n$0vQ*
public void setCountId(int countIds){ eqUn8<<s
this.countId=countIds; ?:;hTY
} #S74C*'8
public String getCountType(){ gmH0-W)=
return countType; 3G0\i!*t
} |8?{JKsg
public int getCountId(){ L1w4WFWO
return countId; ;iI2K/ 3
} 9Yne=R/]
} 46JP1
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CountCache.java <5L` d}
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/* |&*rSp2iH
* CountCache.java Gi_X+os
* wA+4:CF@
* Created on 2007年1月1日, 下午5:01 g(/O)G.
* E*]L]vR
* To change this template, choose Tools | Options and locate the template under B
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* the Source Creation and Management node. Right-click the template and choose #3jZ7RqzQ
* Open. You can then make changes to the template in the Source Editor. G`K7P`m
*/ Z.f<6<gF
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package com.tot.count; l@9:VhU(
import java.util.*; u"3cSuqy
/** E0'6 !9y
* q "vT]=Y}:
* @author #.K&]OV/88
*/ _e^V\O>
public class CountCache { hIHO a
public static LinkedList list=new LinkedList(); hRiGW_t
/** Creates a new instance of CountCache */ g4932_tC
public CountCache() {} :~(^b;yhZ
public static void add(CountBean cb){ V3nv5/6
if(cb!=null){ xpo}YF'5
list.add(cb); XX+rf
} Msdwv.jM
} +1A<kJ
} B9 {DO
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CountControl.java sVf7g?
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/* ;]e"bX
* CountThread.java b?^<';,5
* U%olH >1K
* Created on 2007年1月1日, 下午4:57 {uG_)G Fr0
* Yf9L~K
* To change this template, choose Tools | Options and locate the template under 79fg%cSb
* the Source Creation and Management node. Right-click the template and choose 11'Tt!
* Open. You can then make changes to the template in the Source Editor. #.aLx$"a
*/ Mqy`j9FbL
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package com.tot.count; a+Nd%hoe
import tot.db.DBUtils; S]{Z_|h*j
import java.sql.*; <;K/Yv'{r
/** #,pLVt<
* lDXH<W?
* @author [HfFC3U
*/ sa?;D
public class CountControl{ gr7_oJ:R
private static long lastExecuteTime=0;//上次更新时间 h)8_sC
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ivk|-C'\
/** Creates a new instance of CountThread */ hkxZ=l
public CountControl() {} 'r0gqtB
public synchronized void executeUpdate(){ >?V->7QLP
Connection conn=null;
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PreparedStatement ps=null; &3. 8i%
try{ AJ}Q,E
conn = DBUtils.getConnection(); pQi -
conn.setAutoCommit(false); H9?~#GPb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b"V-!.02
for(int i=0;i<CountCache.list.size();i++){ UYUdIIoL
CountBean cb=(CountBean)CountCache.list.getFirst(); 8a{g EZT,
CountCache.list.removeFirst(); j.*}W4`Q_
ps.setInt(1, cb.getCountId()); a{=~#u8
ps.executeUpdate();⑴ vC1 `m
//ps.addBatch();⑵ |Can
} #c_ZU\"h"
//int [] counts = ps.executeBatch();⑶ aMWNZv
conn.commit(); !k)
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}catch(Exception e){ {s]eXc]K}
e.printStackTrace(); B'yrXa|P
} finally{ i|e-N?l
try{ uNjy&I:
if(ps!=null) { +X%yF{^m(
ps.clearParameters(); |BR&p)7)
ps.close(); YDJc@*D
ps=null; z#b6 aP
} |{(ynZ]R
}catch(SQLException e){} !xSGZD=AD
DBUtils.closeConnection(conn); <ZLs+|1
} T^ -RP
} \}5\^&}_
public long getLast(){ "A7tb39*
return lastExecuteTime; tQ"PCm
} P_}$|zj7
public void run(){ W-MQMHQ
long now = System.currentTimeMillis(); tfO
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if ((now - lastExecuteTime) > executeSep) { EW)]75o{QF
//System.out.print("lastExecuteTime:"+lastExecuteTime); rHznXME$wZ
//System.out.print(" now:"+now+"\n"); xYbF76B
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); />$kDe
lastExecuteTime=now; Y (Q8P{@(
executeUpdate(); g_`8K,6ln
} RAvV[QkT
else{ >i'3\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); v?}/WKe+0
} mYZH]oo
} V'8
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} 2ma.zI@^u9
//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 )57OZ
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类写好了,下面是在JSP中如下调用。 1K!7FiqY
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<%
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CountBean cb=new CountBean(); bR.T94-8y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); umc!KOkL
CountCache.add(cb); |m ~|
out.print(CountCache.list.size()+"<br>"); g\2Y605DM
CountControl c=new CountControl(); ,ua]h8
c.run(); H&I0\upd
out.print(CountCache.list.size()+"<br>"); zk?lNs
%>