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: *=G~26*!V
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CountBean.java ?a)X)#lQ
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/* ,orq*Wd
* CountData.java kT7x
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* <HYK9{Q
* Created on 2007年1月1日, 下午4:44
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* SNLZU%jan
* To change this template, choose Tools | Options and locate the template under sd(Yr6~..
* the Source Creation and Management node. Right-click the template and choose Z]L_{=*
* Open. You can then make changes to the template in the Source Editor. C1V:_-
*/ (i3V[H
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package com.tot.count; R\i8O^[
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/** sGBm[lplz
* A=N &(k
* @author He&7(mQ0^
*/ 4c})LAwd&
public class CountBean { *:r6E
private String countType; *yx5G-#?
int countId; YJ6y]r
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/** Creates a new instance of CountData */ v3zd>fDnRp
public CountBean() {} vw.rkAGY
public void setCountType(String countTypes){ oc|%|pmRd<
this.countType=countTypes; .$ o0$`}
} %R?B=W7;Q
public void setCountId(int countIds){ K[,d9j`^
this.countId=countIds; _1>Xk_
} adCTo
public String getCountType(){ "c+j2f'f
return countType; jRn5)u
} ~ShoU
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public int getCountId(){ N*^iOm]Y
return countId; hq[:U?!Tt
} kU75
} rnOg;|u8
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CountCache.java YGdzA]3>
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/* Xa,d"R~
* CountCache.java >]ghme
* \`kH2`
* Created on 2007年1月1日, 下午5:01 s%cfJe_k
* /
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* To change this template, choose Tools | Options and locate the template under 7O.?I#
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* the Source Creation and Management node. Right-click the template and choose t[r<&1[&
* Open. You can then make changes to the template in the Source Editor. ^X?D4a|;#g
*/ uT
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package com.tot.count; *A^`[_y
import java.util.*; T'W@fif
/** W5)R{w0`GD
* vk1E!T9X
* @author B@+&?%ub:
*/ /r8'stRzv
public class CountCache { og?>Q i Tr
public static LinkedList list=new LinkedList(); #7*{ $v
/** Creates a new instance of CountCache */ $.5f-vQp
public CountCache() {} c4Leh"ry
public static void add(CountBean cb){ :cE6-Fv
if(cb!=null){ )qID<j#
list.add(cb); D4G*Wz8
} 8h?):e
} ~dtS
} HL`=zB%
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CountControl.java |_h$}~;
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/* Nn/f*GDvK
* CountThread.java HxAN&g*:
* 39yp1
* Created on 2007年1月1日, 下午4:57 #/,Wgs AC
* TXWYQ~]3w
* To change this template, choose Tools | Options and locate the template under mVs<XnA47
* the Source Creation and Management node. Right-click the template and choose &i5MRw_]]
* Open. You can then make changes to the template in the Source Editor. sw\O\%^
*/ u3k{s
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package com.tot.count; Gi+ZI{)
import tot.db.DBUtils; W2`/z)[*>
import java.sql.*; yKhN1kY
/** /cXVJ(#j
* {CaTu5\
* @author ZzO^IZKlC
*/ fep8hf B;
public class CountControl{ fxOa(mt
private static long lastExecuteTime=0;//上次更新时间 RxB9c(s^@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 C$x
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/** Creates a new instance of CountThread */ $[6] Ly(F)
public CountControl() {} J$>9UCk7B
public synchronized void executeUpdate(){ k|r|*|8
Connection conn=null; >qL-a*w:a
PreparedStatement ps=null; tb1w 6jaU
try{ #,5v#|u|7
conn = DBUtils.getConnection(); q(XO_1W0V
conn.setAutoCommit(false); n85d
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +oRBSAg -
for(int i=0;i<CountCache.list.size();i++){ +FBUB
CountBean cb=(CountBean)CountCache.list.getFirst(); U3tA"X.K
CountCache.list.removeFirst(); R^f-j-$o]
ps.setInt(1, cb.getCountId()); cYx.<b
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ps.executeUpdate();⑴ z#u<]] 5
//ps.addBatch();⑵ (X?et
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} xV\mS+#
//int [] counts = ps.executeBatch();⑶ c?t,,\o(}
conn.commit(); ]w5j?h"b
}catch(Exception e){ 5<77o|
e.printStackTrace(); +d289"
} finally{ *Z}9S9YtN
try{ gNaB^IY
if(ps!=null) { 8r\;8all
ps.clearParameters(); Y7GHIzX
ps.close(); @\?QZX(H
ps=null; "~,3gNTzV
} 2S@aG%-)
}catch(SQLException e){} gw_]Y^U
DBUtils.closeConnection(conn); ;8iK] ;^
} f2]O5rXp
} TD^w|U.
public long getLast(){ !WgVk7aP`
return lastExecuteTime; C#oH7o+_.
} P+gYLX8
public void run(){ N6<G`k,
long now = System.currentTimeMillis(); \ sc's7
if ((now - lastExecuteTime) > executeSep) { >mCS`D8
//System.out.print("lastExecuteTime:"+lastExecuteTime); egn9O
//System.out.print(" now:"+now+"\n"); iZ;y(
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m[$pj~<\
lastExecuteTime=now; %<yH6h*u
executeUpdate(); }HLV'^"k
} )Q5ja}-{V
else{ |HfN<4NL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); eZvG
} uD8,E!\
} %$ ^eY'-'
} }pOJ M&I
//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 qu+Zl1~$]
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类写好了,下面是在JSP中如下调用。 S&z8-D=8k
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<% ?@iGECll
CountBean cb=new CountBean(); lr~c w#h*
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?Vo/mtbY5X
CountCache.add(cb); W_FN*Er
out.print(CountCache.list.size()+"<br>"); !K8V":1du#
CountControl c=new CountControl(); )ad6>Y
c.run(); $guaUe[x
out.print(CountCache.list.size()+"<br>"); a[hQ<@1O
%>