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: OZb-:!m*
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CountBean.java CmP9Q2
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/* G)AqbY
* CountData.java %^)fmu
* L\6M^r
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* Created on 2007年1月1日, 下午4:44 JK7G/]j+Ez
* A9KET$i@v
* To change this template, choose Tools | Options and locate the template under .Yamc#A-
* the Source Creation and Management node. Right-click the template and choose :(E@Gf
* Open. You can then make changes to the template in the Source Editor. 5N#aXG^9
*/ A]_7}<<N
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package com.tot.count; 2jA {SY-
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/** qJf?o.Pv
* poc`q5i+
* @author -mbt4w
*/ w1FcB$
public class CountBean { +r
private String countType; u4*BX&
int countId; U45e2~1!O
/** Creates a new instance of CountData */ Yj<a"
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public CountBean() {} k90YV(
public void setCountType(String countTypes){ iOf<$f
this.countType=countTypes; vOH4#
} XnH05LQ
public void setCountId(int countIds){ 3p$?,0ELH
this.countId=countIds; i7CX65&b
} u%GEqruo[
public String getCountType(){ %HhBt5w
return countType; ,5P0S0*{
} [CTnXb
public int getCountId(){ +WZX.D
return countId; k`cfG\;r
} ^L,K& Jd
} =bAx,,D#
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CountCache.java +X\FBvP&
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/* vJLK,[
* CountCache.java s2a{>II6
* {Ea
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* Created on 2007年1月1日, 下午5:01 xf'V{9*
* bS{bkE>
* To change this template, choose Tools | Options and locate the template under W Tcw4
* the Source Creation and Management node. Right-click the template and choose ;_XFo&@
* Open. You can then make changes to the template in the Source Editor. nd`1m[7MNu
*/ PioZIb/{
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package com.tot.count; av(6wht8
import java.util.*; 3RUy,s
/** fQ7V/x!
* 7kC^
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* @author +Z,;,5'5G
*/ Hkg2P,2
public class CountCache { #QZe,"C9`
public static LinkedList list=new LinkedList(); 5f rX
/** Creates a new instance of CountCache */ 9v#CE!
public CountCache() {} k<z)WNBf
public static void add(CountBean cb){ b8H{8{wi|
if(cb!=null){ 5G}?fSQ>
list.add(cb); Q1lyj7c#x
} V~qNyOtA]
} ~\r*
} ),_@WW;k
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CountControl.java n5|fHk^s
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/* "BAK !N$9
* CountThread.java xKbXt;l2
* SA:Zc^aV
* Created on 2007年1月1日, 下午4:57 r[e##M
* (xycJ`N
* To change this template, choose Tools | Options and locate the template under ?C]vS_jAh
* the Source Creation and Management node. Right-click the template and choose 6dHOf,zjm
* Open. You can then make changes to the template in the Source Editor. pG_;$8Hc
*/ k``_EiV4t
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package com.tot.count; iG$!6;w<
import tot.db.DBUtils; `4r 3l S
import java.sql.*; {.`vs;U
/** @?ebuj5{e
* ]IaMp788
* @author zg>zUe
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*/ "2!&5s,1p
public class CountControl{ C-xr"]#]
private static long lastExecuteTime=0;//上次更新时间 @b\$ yB@z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `&qL(66
/** Creates a new instance of CountThread */ W@>% {eE
public CountControl() {} &{5,:%PXw
public synchronized void executeUpdate(){ VCYwzB
Connection conn=null; bt SRtf
PreparedStatement ps=null; Y!xF;a
try{ Fk7?xc
conn = DBUtils.getConnection(); "> ypIR<
conn.setAutoCommit(false); .Cv6kgB@c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8H[<X_/ke
for(int i=0;i<CountCache.list.size();i++){ Y+pHd\$-4
CountBean cb=(CountBean)CountCache.list.getFirst(); TT%M'5&
CountCache.list.removeFirst(); _IMW{
ps.setInt(1, cb.getCountId()); YO`]UQ|dc
ps.executeUpdate();⑴ qfF~D0}
//ps.addBatch();⑵ D'>_I.
} cbjs9bu
//int [] counts = ps.executeBatch();⑶ H.P_]3f
conn.commit(); #&+{mCjs
}catch(Exception e){ 3=#<X-);
e.printStackTrace(); E#RDqL*J
} finally{ xH4m|
try{ xa'*P=<)C'
if(ps!=null) { F-Qzrqu S
ps.clearParameters(); Xxj-
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ps.close(); 8bGd} (
ps=null; Mc
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} ]2A^1Del
}catch(SQLException e){} ;7*[Bcj.
DBUtils.closeConnection(conn); >fG3K`
} 6{K,c@VFd
} _`$qBw.Nx
public long getLast(){ U)TUOwF
return lastExecuteTime; 299H$$WS,Z
} !vi>U|rh
public void run(){ D_ 2:k'4
long now = System.currentTimeMillis(); ]|pe>:gf'
if ((now - lastExecuteTime) > executeSep) { _oL?*ks
//System.out.print("lastExecuteTime:"+lastExecuteTime); umBICC]CU
//System.out.print(" now:"+now+"\n"); W ~<^L\Lu
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); y8y5*e~A-)
lastExecuteTime=now; 1dY}\Sp
executeUpdate(); K`eCDvlH
} %fZJRu
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else{ ';Ea?ID
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); UBKu/@[f@
} n6=By|jRh
} D>r&}6<
} &A/]pi-\
//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 0q
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类写好了,下面是在JSP中如下调用。 0|q AxR-
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<%
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CountBean cb=new CountBean(); ;<Sd~M4f
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )6MfRw
CountCache.add(cb); ?PxP% $hS
out.print(CountCache.list.size()+"<br>"); ~hH REI&
CountControl c=new CountControl(); ;1W6G=m
c.run(); <V'@ks%
out.print(CountCache.list.size()+"<br>"); L- iy
%>