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: WO9vOS>
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CountBean.java 'D`lVUB
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/* 9-{ +U,3)
* CountData.java KG(FA
* BC_<1
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* Created on 2007年1月1日, 下午4:44 HLqN=vE6
* 5<`83;R9
* To change this template, choose Tools | Options and locate the template under zE1=P/N
* the Source Creation and Management node. Right-click the template and choose BaI-ve
* Open. You can then make changes to the template in the Source Editor. Hs8JJGXWB
*/ mD% qDKI
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package com.tot.count; qzO Rv
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/** w@R" g%k-
* $PRd'YdL/
* @author Q~ Ad{yC
*/ %hBwc#^
public class CountBean { 8r"-3<*
private String countType; `a[fC9
int countId; .YvIVQ
/** Creates a new instance of CountData */ "{E%Y*
public CountBean() {} _8y4U[L
public void setCountType(String countTypes){ MtPdpm6\
this.countType=countTypes; /^jl||'H,:
} vs+aUT C\
public void setCountId(int countIds){ f,6V#,
this.countId=countIds; V\L%*6O
} :%AEwRZ
public String getCountType(){ )i.pE]!+
return countType; Y=Ic<WHR
} tMP"9JE,
public int getCountId(){ 0S>L0qp
return countId; ](n)bF+ym
} -{Ar5) ?='
} N<4 nb
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CountCache.java ]G8"\J4 &
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/* B>cT<B
* CountCache.java ;<T,W[3J
* 3rHn?
* Created on 2007年1月1日, 下午5:01 +Tx_q1/f5X
* .]4MtG
* To change this template, choose Tools | Options and locate the template under 9dAtQwGR"6
* the Source Creation and Management node. Right-click the template and choose -~JYfj@
* Open. You can then make changes to the template in the Source Editor. b|E ZD3y
*/ $.w$x1
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package com.tot.count; [r Nd7-j <
import java.util.*; #ucb
/** :t "_I
* @x!+_z
* @author %#&njP
*/ !'[?cEog
public class CountCache { 0!0o[3*
public static LinkedList list=new LinkedList(); >/ A'G
/** Creates a new instance of CountCache */ `x >6Wk1
public CountCache() {} n`w]? bL
public static void add(CountBean cb){ &\cS{35
if(cb!=null){ Val"vUZ
list.add(cb); c1a$J`
} ="vg/@.>i
} q7soV(P
} T2rBH]5
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CountControl.java }f}? |&q
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/* yw7(!1j=
* CountThread.java {{M/=WqC
* Uzrf,I[
* Created on 2007年1月1日, 下午4:57 3>MILEY^
* T"X]@9g^-
* To change this template, choose Tools | Options and locate the template under /~;!Ew|q
* the Source Creation and Management node. Right-click the template and choose 'PFjZGaKR
* Open. You can then make changes to the template in the Source Editor. [dFcxzM-N
*/ -Edy ~;_
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package com.tot.count; Hsv)]
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import tot.db.DBUtils; /#@tv~Z^
import java.sql.*; yk5K8D[tV
/** -Hw3rv3o
* x6!Q''f7
* @author m2l9([u=^
*/ c[ 0`8s!
public class CountControl{ ln8NcAEx
private static long lastExecuteTime=0;//上次更新时间 6dz^%Ub
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 s7:H
/** Creates a new instance of CountThread */ P3=#<Q.
public CountControl() {} >35w"a7S
public synchronized void executeUpdate(){ ZPb30M0
Connection conn=null; >!']w{G
PreparedStatement ps=null; M,li\)J!&
try{ aTeW#:m
conn = DBUtils.getConnection(); @>~\So|
conn.setAutoCommit(false); SVn@q|N
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); lic-68T
for(int i=0;i<CountCache.list.size();i++){ kMnG1K
CountBean cb=(CountBean)CountCache.list.getFirst(); pO:]3qv
CountCache.list.removeFirst(); yx4pQL7
ps.setInt(1, cb.getCountId()); >C6S2ISSz
ps.executeUpdate();⑴ u1#(~[.
//ps.addBatch();⑵ m$v >r\*X
} u'_}4qhCC;
//int [] counts = ps.executeBatch();⑶ H6jt[
conn.commit(); m}RZ)c
}catch(Exception e){ xypgG;`\
e.printStackTrace(); 0hGmOUO
} finally{ a9{NAyl<oo
try{ Zxqlhq/)
if(ps!=null) { C|3Xz[k{
ps.clearParameters(); &}2@pu[S?7
ps.close(); zSfUM.fM
ps=null; !-3;Qj}V
} Z^as ?k(iM
}catch(SQLException e){} /Qr`au
DBUtils.closeConnection(conn); Q25VG5G
} q
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} =G^'wwpv(
public long getLast(){ e_KfnPY
return lastExecuteTime; xYYa%PhIC
} GxG~J4
public void run(){ y'4Qt.1ukN
long now = System.currentTimeMillis(); +> !nqp
if ((now - lastExecuteTime) > executeSep) { (Ll'j0]k>
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ow4(1eE_
//System.out.print(" now:"+now+"\n"); >jIn&s!}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); t ;h`nH[
lastExecuteTime=now; jTt9;?)
executeUpdate(); !Pnjr T
} ; xp-MK
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +D]raU
} (,QWK08
} xt,Qn460;
} Bz-jy.
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 JOt(r}gU
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类写好了,下面是在JSP中如下调用。 ;2&"
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<% 6Nn+7z<*&z
CountBean cb=new CountBean(); GVnDN~[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); I(pq3_9$
CountCache.add(cb); ?%Nh4+3N>
out.print(CountCache.list.size()+"<br>"); 04;s@\yX4
CountControl c=new CountControl(); ^-k"gLg
c.run(); k"&o)*d
out.print(CountCache.list.size()+"<br>"); $B%KkD
%>