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: Sf/W9Jw
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CountBean.java R=86w_
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/* Y_lCcu#OA
* CountData.java R `Q?J[e
* 0 r3N^_}
* Created on 2007年1月1日, 下午4:44 /MxCvEE
* W_D%|Ub2X
* To change this template, choose Tools | Options and locate the template under C~_q^fXJt
* the Source Creation and Management node. Right-click the template and choose hvcR.f)C>
* Open. You can then make changes to the template in the Source Editor. YiNo#M91
*/ c#x7N9;"!
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package com.tot.count; ] - h|]
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/** -;S3|
* F]SIT\kBm
* @author c8\g"T
*/ skSNzF7'
public class CountBean { 3H <`Z4;
private String countType; gQCC>8
int countId; C=EhY+5
/** Creates a new instance of CountData */ qKx59
public CountBean() {} Oo$%Yh51~
public void setCountType(String countTypes){ SmvwhX
this.countType=countTypes; MHn&;
A]
} bY&YSlO
public void setCountId(int countIds){ `7$Oh{67
this.countId=countIds; v6(,Ax&
} ^EUQ449<p
public String getCountType(){ ^CX,nj_(
return countType; EKJH_!%
} IjgBa-o/V
public int getCountId(){ jaNH](V
return countId; '[xut1{
} {cX7<7N
} B8>FCF&}E
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CountCache.java "$4hv6 s
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/* B~e7w 4
* CountCache.java U(8I+xZ
* su%Z{f)#
* Created on 2007年1月1日, 下午5:01 _"`uqW79
* Z#[>N,P
* To change this template, choose Tools | Options and locate the template under v@]6<e$
* the Source Creation and Management node. Right-click the template and choose uvNnW}G4
* Open. You can then make changes to the template in the Source Editor. {<~s&EPd
*/ W *|OOa'
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package com.tot.count; BD?F`%-x
import java.util.*; 9EjjkJ%)q
/** HMFl/%z
* YU*46 hA1B
* @author r)(i{:@r`
*/ s2wwmtUCN
public class CountCache { _{3k+DQ
public static LinkedList list=new LinkedList(); .v$ue`
/** Creates a new instance of CountCache */ IcO9V<Q|
public CountCache() {} &0FpP&Z(
public static void add(CountBean cb){ h^Arb=I
if(cb!=null){ Sk!v,gx
list.add(cb); =/M$
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} zww?
} cRjL3
} !~Ax
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CountControl.java i:AjWC@]
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/* H,/~=d:
^
* CountThread.java /{49I,
* [%7IQ4`{
* Created on 2007年1月1日, 下午4:57 60(}_%
* 8UjCX[v
* To change this template, choose Tools | Options and locate the template under t
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* 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. ~mHXz
*/ ^ON-#
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package com.tot.count; CvgPIrl
import tot.db.DBUtils; MM/BJ
import java.sql.*; /5a$@%
/** tP/GDC;
* cob9hj#&7
* @author mNGb}
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*/ eimA *0Cq
public class CountControl{ U1OLI]P
private static long lastExecuteTime=0;//上次更新时间 }6yxt9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 q{jk.:;'
/** Creates a new instance of CountThread */ 5EVB27k
public CountControl() {} }39M_4a&
public synchronized void executeUpdate(){ DtI%-I.
Connection conn=null; rin >r0o
PreparedStatement ps=null; iA5*
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try{ 1gf/#+$\
conn = DBUtils.getConnection(); ]Hv*^Bak
conn.setAutoCommit(false); e2,<,~_K6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;D%5 nnr
for(int i=0;i<CountCache.list.size();i++){ [)T$91
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CountBean cb=(CountBean)CountCache.list.getFirst(); :*^(OnIe
CountCache.list.removeFirst(); i2`.#YJ&v
ps.setInt(1, cb.getCountId()); )dUd `g
ps.executeUpdate();⑴ ;+aDjO2(
//ps.addBatch();⑵ PprQq_j
} /zDSlj<c
//int [] counts = ps.executeBatch();⑶ YA1{-7'Q
conn.commit(); q(w1VcLZ
}catch(Exception e){ q[Sp|C6x
e.printStackTrace(); N6-2*ES
} finally{ Ae,2Xi
try{ ?];~N5<'
if(ps!=null) { )w3XN A_V
ps.clearParameters(); i2\\!s
ps.close(); x);?jxd
ps=null; /cn/[O9
} 3P=Eb!qtdD
}catch(SQLException e){} ba8-XA_~U
DBUtils.closeConnection(conn); T-<> )N5y
} uv_P{%TK
} ;mM\,
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public long getLast(){ 6+{ nw}e8
return lastExecuteTime; ={wjeRp
} O(:u( U7e
public void run(){ #I*ht0++
long now = System.currentTimeMillis(); 7csl1|U
if ((now - lastExecuteTime) > executeSep) { 7,&3=R<
//System.out.print("lastExecuteTime:"+lastExecuteTime); z}Mb4{d1
//System.out.print(" now:"+now+"\n"); '/]fZ|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #Fb0;H9`
lastExecuteTime=now; [|P]St-
executeUpdate(); } SWA|x
} ZJ{+_ax0K
else{ cfO^CC
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); )f_"`FH0d
} k[^}ld[
}
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} "O"^\f
//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 d-K5nRyI
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类写好了,下面是在JSP中如下调用。 cl9;2D"Zm!
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<% R`<{W(J;r
CountBean cb=new CountBean(); $`+~QR!h
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); BGk<NEzH
CountCache.add(cb); 2EI m
out.print(CountCache.list.size()+"<br>"); {f6A[ZO; J
CountControl c=new CountControl(); ^LQ lfd
c.run(); )H=[NB6J8
out.print(CountCache.list.size()+"<br>"); 'f$?/5@@
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