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:
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CountBean.java fjo{av~]y
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/* pi( -A
* CountData.java LVIAF0kX
* MOn,Db$
* Created on 2007年1月1日, 下午4:44 4:3rc7_
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* pN6%&@) =
* To change this template, choose Tools | Options and locate the template under 2 gq$C"
* the Source Creation and Management node. Right-click the template and choose s6*ilq1
* Open. You can then make changes to the template in the Source Editor. os3 8u!3-
*/ dCYCHHHF
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package com.tot.count; RhI;;Y#@
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/** EqiFy"H
* snM Z0W
* @author )O+}T5c=
*/ t9gfU5?
public class CountBean { a`9L,8Ve
private String countType; )"(] Lf's
int countId; ! hd</_#
/** Creates a new instance of CountData */ !{et8F@d|
public CountBean() {} 8VG!TpX/B
public void setCountType(String countTypes){ <`X"}I3ba
this.countType=countTypes; "eWk#/
} c:S] R"
public void setCountId(int countIds){ ',3HlOJ:
this.countId=countIds; ~9^)wCM+
} VLsxdwHgb
public String getCountType(){ 'X).y1'
return countType; %R#L
} X5fmz%VK@
public int getCountId(){ mOpTzg@
return countId; exh/CK4;
} H~eRT1
} 2n><RZ/9
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CountCache.java <99M@ cF
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/* -U~
* CountCache.java #Lsnr.80
* a8u9aEB
* Created on 2007年1月1日, 下午5:01 &uP~rEJl+
* #ywk|k5z]
* To change this template, choose Tools | Options and locate the template under J{ [n?/A{
* the Source Creation and Management node. Right-click the template and choose ')a(.f
* Open. You can then make changes to the template in the Source Editor. hPq%Lc
*/ }nt*
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package com.tot.count; Vc^HVyAx@n
import java.util.*; r|4t aV&
/** *"9><lJ-!
* fA'qd.{f^
* @author 8eA+d5k\.
*/ tg^sCxz9]
public class CountCache { _X~87
public static LinkedList list=new LinkedList(); js1!9%BV
/** Creates a new instance of CountCache */ ( mxT2"fC
public CountCache() {} C]^H&
public static void add(CountBean cb){ r&-m=Kk$
if(cb!=null){ 'mI'dG
list.add(cb); [m^+,%m5]
} j4=(H:c~E
} 1[_mEtM:]B
} 2r$#m*
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CountControl.java oYWR')8g
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/* -}K<ni6
* CountThread.java t1E[uu ,V8
* aq7~QX_0G
* Created on 2007年1月1日, 下午4:57 >#ZUfm{k$
* f#ri'&}c
:
* To change this template, choose Tools | Options and locate the template under JNcYJ[wqv
* the Source Creation and Management node. Right-click the template and choose 4k./(f2+
* Open. You can then make changes to the template in the Source Editor. c8Z wr]DF
*/ cqxVAzb
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package com.tot.count; oyo(1>
import tot.db.DBUtils; J>d.dq>r
import java.sql.*; .`?@%{
/** ){jla,[
* h gJ[LU| >
* @author ybp -$e
*/ E*i#?u
public class CountControl{ Z`YJBcXR
private static long lastExecuteTime=0;//上次更新时间 Z|}G6]h
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 vq34/c^
/** Creates a new instance of CountThread */ !?Wp+e6
public CountControl() {} uwlr9nB
public synchronized void executeUpdate(){
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Connection conn=null; dH( ('u[
PreparedStatement ps=null; ;#Q%j%J
try{ LR"9D
conn = DBUtils.getConnection(); 6;b~Ht
conn.setAutoCommit(false); ;;&}5jcV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); T0]MuIJ).
for(int i=0;i<CountCache.list.size();i++){ v+99
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CountBean cb=(CountBean)CountCache.list.getFirst(); Uix6GT;
CountCache.list.removeFirst(); # W"=ry3{
ps.setInt(1, cb.getCountId()); nB .G
ps.executeUpdate();⑴ [`
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//ps.addBatch();⑵ nT2)E&U6%
} ToYAW,U[d
//int [] counts = ps.executeBatch();⑶ :6%Z]tt
conn.commit(); Yw0[[N<SW
}catch(Exception e){ ?IpLf\n-
e.printStackTrace(); DK}"b}Fvq
} finally{ 43=,yz2Ef
try{ o=`C<}
if(ps!=null) { G8Du~h!!U
ps.clearParameters(); L@fY$Rw
ps.close(); ?,/U^rf^4
ps=null; 3do)Vg4
} 1) Zf3Y8
}catch(SQLException e){} B$Kn1 k
DBUtils.closeConnection(conn); "jw<V,,
} cph:y
} X]y)qV)a[c
public long getLast(){ 13Lr}M&
return lastExecuteTime; {5
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} K<>sOWZ'S
public void run(){ &4_qF^9J
long now = System.currentTimeMillis(); 3h<,
if ((now - lastExecuteTime) > executeSep) { ZK)%l~J
//System.out.print("lastExecuteTime:"+lastExecuteTime); j1(D]Z=\
//System.out.print(" now:"+now+"\n"); ,~._}E&9I
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Q$fmD
lastExecuteTime=now; M'/aZ#
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executeUpdate(); TiH)5
} B/n[m@O
else{ $kQ~d8 O
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); mml
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} HJY2#lSha6
} r
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} ccL~#c0P7
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 //aF5:Y#
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类写好了,下面是在JSP中如下调用。 ,GgAsj: K
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<% Sfr&p>{,
CountBean cb=new CountBean(); ?^N3&ukkyo
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 3g6j?yYqb
CountCache.add(cb); L{c q, jk
out.print(CountCache.list.size()+"<br>"); >
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CountControl c=new CountControl(); <'g:T(t
c.run(); bAx?&$
out.print(CountCache.list.size()+"<br>"); QNl'ZB\
%>