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: /^`do3a}
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CountBean.java 880T'5}S
:
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/* \M*c3\&~,e
* CountData.java gi8f)MNP?~
* f;bfR&v
* Created on 2007年1月1日, 下午4:44 5+/XO>P1m|
* :]8!G- Z
* To change this template, choose Tools | Options and locate the template under 2HDWlUTNVO
* the Source Creation and Management node. Right-click the template and choose yz%o?%@
* Open. You can then make changes to the template in the Source Editor. Yb'%J@T}
*/ '.I0n
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package com.tot.count; Q776cj^L
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/** fD2 N}
* 2>xEE
* @author H$6;{IUz~
*/ M4t:)!dji?
public class CountBean { pwNF\ ={
private String countType; Z5"5Ge-M
int countId; ,fhK
/** Creates a new instance of CountData */ RZ?abE8
public CountBean() {} =V:Al
public void setCountType(String countTypes){ <{z-<D;
this.countType=countTypes; N\fj[?f[
} Wyb+K)Tg
public void setCountId(int countIds){ z#d*Odc
this.countId=countIds; -s7a\H{~
} zo1fUsK?
public String getCountType(){ >ni0:^vp
return countType; w`F'loUEt
} gdg
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public int getCountId(){ >Xxi2Vy
return countId; SjvSnb_3
} dfXBgsc6i
} :\%ZTBLL
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CountCache.java i`!>zl+D
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/* p,3}A(>
* CountCache.java 352RJC
* ;/!o0:m^I
* Created on 2007年1月1日, 下午5:01 3E!3kSh|
* bMqFrG
* To change this template, choose Tools | Options and locate the template under {wf5HA
* the Source Creation and Management node. Right-click the template and choose u/J1Z>0
* Open. You can then make changes to the template in the Source Editor. RvyCc!d
*/ HgTBON(
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package com.tot.count; Y,-!QFS#
import java.util.*; @={
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/** pwA~?$B1
* =TA8]7S~U
* @author 7LiyA<
*/ a._>?rVy
public class CountCache { vJ>o9:(6
public static LinkedList list=new LinkedList(); ((6?b5[
/** Creates a new instance of CountCache */ {v2[x W
public CountCache() {} Ys<z%
public static void add(CountBean cb){ )hD77(c
if(cb!=null){ s@*i
list.add(cb); {O4&HW%
} Xc<Hm
} !^Q4ZL,-
} ;Ao`yC2(v
sRC?l_n;
CountControl.java S) `@)sr
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/* n9V8A[QJ
* CountThread.java 5e^z]j1Yv
* 5a:YzQ4
* Created on 2007年1月1日, 下午4:57 OUy}1%HY
* 9 6%N
* To change this template, choose Tools | Options and locate the template under n
m.5!.
* the Source Creation and Management node. Right-click the template and choose WdbHT|.Aj
* Open. You can then make changes to the template in the Source Editor. [f]:hJi
*/ !j9(%,PR
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package com.tot.count; Qa"4^s
import tot.db.DBUtils; "J2v8c
import java.sql.*; &
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/** dA0o{[o=
* pbGv\SF
* @author tQ)l4Y 8
*/ >KJE *X@s
public class CountControl{ A"IaFXB
private static long lastExecuteTime=0;//上次更新时间 S"@@BQ#mf
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &Zo+F]3d
/** Creates a new instance of CountThread */ D 75;Y;E
public CountControl() {} %z-n2%
public synchronized void executeUpdate(){ Wli!s~c5Fo
Connection conn=null; w^[:wzF0
PreparedStatement ps=null; p@wtT"Y
try{ GYV%RD #
conn = DBUtils.getConnection(); xiF}{25a
conn.setAutoCommit(false); v3cLU7bi?2
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /Y[ b8f
for(int i=0;i<CountCache.list.size();i++){ $I9U.~*
CountBean cb=(CountBean)CountCache.list.getFirst(); nQG<OVRClS
CountCache.list.removeFirst(); yjM!M|
ps.setInt(1, cb.getCountId()); 8L*#zaSAf
ps.executeUpdate();⑴ ~31-)*tJ]
//ps.addBatch();⑵ 4\ny]A:~
} ?_.
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//int [] counts = ps.executeBatch();⑶ Pxgal4{6
conn.commit(); 8Y;2.Z`Rz
}catch(Exception e){ g>{t>B%v^K
e.printStackTrace(); j+2-Xy'
} finally{
g ~%IA.$c
try{ Or-LQ^~
if(ps!=null) { qKs"L^b
ps.clearParameters(); n.1$p
ps.close(); uIR
ps=null; u\)q.`
} ZpZoOdjslV
}catch(SQLException e){} 1czU$!MV
DBUtils.closeConnection(conn); 7Kti&T
} a)!R4
} *]ME]2qP
public long getLast(){ 8x9;3{R
return lastExecuteTime; #y1M1O g
} Jjh=zxR>
public void run(){ $LtCI
long now = System.currentTimeMillis(); >n%ckL|rG
if ((now - lastExecuteTime) > executeSep) { Kp6%=JjO
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3Q_)Xs
r`
//System.out.print(" now:"+now+"\n"); )b,FE}YX
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); hO(A_Bw
lastExecuteTime=now; 8*eVP*g
executeUpdate(); +>:[irf
} (lvp-<*
else{ _SQ]\Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); )~#3A@
} F`o"t]AD-a
} unyU|B
} \3O1o#=(
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ,N8SP
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类写好了,下面是在JSP中如下调用。 ;B;wU.Y"
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<% ~ _ko$(;A
CountBean cb=new CountBean(); && WEBQ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); r`PD}6\
CountCache.add(cb); +SkfT4*U
out.print(CountCache.list.size()+"<br>"); ePTxuCf>
CountControl c=new CountControl(); >vNE3S_
c.run(); $Eo-58<q
out.print(CountCache.list.size()+"<br>"); s2 $w>L
%>