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: ;X*cCb`h
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CountBean.java "&/-N[is
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/* '5&s=M_
* CountData.java 8NyJc"T<.
* [
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* Created on 2007年1月1日, 下午4:44 kuyjnSo9i
* WSuww
* To change this template, choose Tools | Options and locate the template under y;_% W
* the Source Creation and Management node. Right-click the template and choose n]E?3UGD@W
* Open. You can then make changes to the template in the Source Editor. okbQ<{9
*/ {~Rk2:gx
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package com.tot.count; yw];P
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/** wgCa58H76
* M#(+c_(r
* @author *G*
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*/ *98$dQR$
public class CountBean { ^R:cd8+?%
private String countType; "[y-+)WTG
int countId; ^fZ&QK
/** Creates a new instance of CountData */ s"t$0cH9
public CountBean() {} >=[(^l
public void setCountType(String countTypes){ 'Lu__NfN
this.countType=countTypes; JvY}-}?c
} H$y-8-&)
public void setCountId(int countIds){ /~zai}
this.countId=countIds; 8F._9U-EN
} &Z`#cMR{H
public String getCountType(){ hCC<?5q
return countType; ^]TVo\,N
} c%MW\qx
public int getCountId(){ <J^MCqp!v
return countId; %i5M77#Z
} Hy^N!rBxfO
} q
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CountCache.java l<A|d{" ]
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/* @3zg=?3
* CountCache.java V$ps>
* +0OLc2
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* Created on 2007年1月1日, 下午5:01 tCdqh-
* ZpnxecJUJ
* To change this template, choose Tools | Options and locate the template under Za1QC;7
* the Source Creation and Management node. Right-click the template and choose "1%5,
* Open. You can then make changes to the template in the Source Editor. UEguF&
*/ $m/)FnU/
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package com.tot.count; )c)vTZy
import java.util.*; [n:<8ho
/** }hhGu\
* !O<)\)|g
* @author "g1)f"pL
*/ T\D}kQM
public class CountCache { ,^2>k3=
public static LinkedList list=new LinkedList(); c-(UhN3WG
/** Creates a new instance of CountCache */ tNbN7yI
public CountCache() {} (jAg_$6
public static void add(CountBean cb){ s+<Yg$)
if(cb!=null){ h-`}L=
list.add(cb); njputEGX
} >&}%+r\
} . QBF`Rz
} UWd=!h^dt
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CountControl.java Jcrw#l8|C
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/* PamO8^!G
* CountThread.java rR(X9i
* =Jyu4j *}
* Created on 2007年1月1日, 下午4:57 iMDM1}b
* Xg;}R:g '
* To change this template, choose Tools | Options and locate the template under cWe"%I
* the Source Creation and Management node. Right-click the template and choose KV0]m^@x
* Open. You can then make changes to the template in the Source Editor. v@
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*/ @U& QI*
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package com.tot.count; X:nN0p #
import tot.db.DBUtils; "W955?4m
import java.sql.*; W*),y:
/** n<z[J=I
* %D\[*
* @author 3
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*/ l*d(;AR
public class CountControl{ :LW4E9O=H
private static long lastExecuteTime=0;//上次更新时间 GLeK'0Q@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 f Sa"%8%
/** Creates a new instance of CountThread */ "hH.#5j
public CountControl() {} l~w2B>i)
public synchronized void executeUpdate(){ 3sy (vC
Connection conn=null; ;;6uw\6
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PreparedStatement ps=null; !Fd~~v
try{ a%/9v"}
conn = DBUtils.getConnection(); s@K4u^$A
conn.setAutoCommit(false); .$+#1-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2fnkw/
for(int i=0;i<CountCache.list.size();i++){ 0=2@
CountBean cb=(CountBean)CountCache.list.getFirst(); b*c*r dTx
CountCache.list.removeFirst(); TJ6*t!'*X
ps.setInt(1, cb.getCountId()); A>o*t=5
ps.executeUpdate();⑴ 5K>3My#
//ps.addBatch();⑵ +0nJ
} dMv=gdY
//int [] counts = ps.executeBatch();⑶ nrub*BuA
conn.commit(); (X\@t-8
}catch(Exception e){ JfLqtXF[&"
e.printStackTrace(); l5!|I:/*;
} finally{ R{<kW9!
try{ Q ayPo]O
if(ps!=null) { jaII r06
ps.clearParameters(); OEA&~4&{7
ps.close(); 'vbsv T
ps=null; n|9-KTe7|*
} <Tzrj1"Q3
}catch(SQLException e){} D9^h;
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DBUtils.closeConnection(conn); Z>:NPZODf
} Vc&!OE
} p6>Svcc
public long getLast(){ 8lvV4yb
return lastExecuteTime; S9]'?|
} =.Pw`.
public void run(){ S"NqM[W
long now = System.currentTimeMillis(); I_}SB|
if ((now - lastExecuteTime) > executeSep) { CkOz
//System.out.print("lastExecuteTime:"+lastExecuteTime); c|e~BQdRw
//System.out.print(" now:"+now+"\n"); [%y';`( x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [1g8*j~L
lastExecuteTime=now; zy/@
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executeUpdate(); a*lh)l<KV
} pjKWtY@=X
else{ `VA"vwz
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =Y{(%sn
} <\rT%f}3^
} UZ\u;/}
}
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//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 _|kxY'_[8
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类写好了,下面是在JSP中如下调用。 P{kur} T
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<% j4gF;-m<
CountBean cb=new CountBean(); N.,X<G.H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t3 8m'J :>
CountCache.add(cb); BO~0ON0
out.print(CountCache.list.size()+"<br>"); HVR /7&g
CountControl c=new CountControl(); S 6@u@C
c.run(); 4KhV|#-;k
out.print(CountCache.list.size()+"<br>"); i1ixi\P{0
%>