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: 3a.kBzus
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CountBean.java Q+4Xs.#
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/* tOfg?)h{dc
* CountData.java ]-ZEWt6lsc
* me[DmiM,
* Created on 2007年1月1日, 下午4:44 ylt`*|$
* 0-~\
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* To change this template, choose Tools | Options and locate the template under X]\ \,
* the Source Creation and Management node. Right-click the template and choose :_!8
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* Open. You can then make changes to the template in the Source Editor. N<QXmgqx
*/ c478P=g=5
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package com.tot.count; >3z5ww
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/** 8\{^|y9-
* X]P:CY
* @author C@th O
*/ W 4F \}A
public class CountBean { k0T?-iM
private String countType; )M)7"PC
int countId; v|U(+O
/** Creates a new instance of CountData */ ZDbc
public CountBean() {} Me
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public void setCountType(String countTypes){ |SyMngIY
this.countType=countTypes; [Q=dCX9%
} ^^5&QSB:'
public void setCountId(int countIds){ 8Y5
this.countId=countIds; v{}#?=I5
} 0v9rv.Y"
public String getCountType(){ Iu$K i
return countType; lP<:tR~K
} '` pDngX
public int getCountId(){ G "73=8d
return countId; ~%YBI9$+
} *zr(Zv
} 6`f2-f9%iq
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CountCache.java cReB~wk
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/* 33!oS&L
* CountCache.java o7|eMe?<t
* ]xuG&O"SBV
* Created on 2007年1月1日, 下午5:01 trAkcYd
* <:?r:fQX
* To change this template, choose Tools | Options and locate the template under OF\rgz
* the Source Creation and Management node. Right-click the template and choose L'u\w
* Open. You can then make changes to the template in the Source Editor. @|\}.M<e*)
*/ U"Zmv
O }
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package com.tot.count; ^MVkZ{gtre
import java.util.*; 9/nn)soC3
/** V{JAB]?^
* 6L)%T02C
* @author -;'1^
*/ R)c'#St
public class CountCache { 3D2E?$dX
public static LinkedList list=new LinkedList(); L21VS ,#I
/** Creates a new instance of CountCache */ 9=UkV\m)
public CountCache() {} b j'Xg
public static void add(CountBean cb){ >uSy
if(cb!=null){ ';<0/U
list.add(cb); xXM{pd
} utIX %0
} Nqu>6^-z0
} }K&7%N4LZ
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CountControl.java ]w.;4`l*
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/* 9]@A]p!
* CountThread.java d+'p@!W_
* ariLG [:X
* Created on 2007年1月1日, 下午4:57 nJo`B4'U
* NUp<e%zB
* To change this template, choose Tools | Options and locate the template under %@u;5qD&
* the Source Creation and Management node. Right-click the template and choose Sv +IS
* Open. You can then make changes to the template in the Source Editor.
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*/ NgY=&W,
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package com.tot.count; :53)Nv
import tot.db.DBUtils; _]Zs,Hy
import java.sql.*; q#s,-u u
/** !TUrQ
* ,gS;m
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* @author m&?#;J|B$
*/ +u3=dj"[
public class CountControl{ h-%R<[
private static long lastExecuteTime=0;//上次更新时间 nX=$EQiH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 BG<q IQd
/** Creates a new instance of CountThread */ :$n=$C-wp
public CountControl() {} \ioH\9
public synchronized void executeUpdate(){ {j7uv"|X7
Connection conn=null; ^pYxKU_O
PreparedStatement ps=null; *m#Za<_Gv
try{ yrlf+tl
conn = DBUtils.getConnection(); AT%u%cE-
conn.setAutoCommit(false); ' hs2RSq
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @w?P7P<O`
for(int i=0;i<CountCache.list.size();i++){ #Jw1IcuH
CountBean cb=(CountBean)CountCache.list.getFirst(); }yz (xH
CountCache.list.removeFirst(); Jl&-,Vjb
ps.setInt(1, cb.getCountId()); Dp':oJC
ps.executeUpdate();⑴ 2n|K5FR()
//ps.addBatch();⑵ 3J5!oF{H
} 'JRvP!]
//int [] counts = ps.executeBatch();⑶ `tn{ei
conn.commit(); >Vwc3d
}catch(Exception e){ hK_LEwd;
e.printStackTrace(); aP/T<QZ~
} finally{ rsy'q(N[
try{ F 9@h|#an
if(ps!=null) { ~FN9 [aJF+
ps.clearParameters(); zaK#Z?V}
ps.close(); lb3]$Da
ps=null; urjjw.wZ
} 0`[wpZ
}catch(SQLException e){} m5r7
DBUtils.closeConnection(conn); N9v1[~ bv_
} ]VD|xm:kj
} nuw70*ell
public long getLast(){ W#hj 1
return lastExecuteTime; i ~{Ufi
} Ac<Phy-J
public void run(){ f>N!wgo[
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { ~W{2Jd
//System.out.print("lastExecuteTime:"+lastExecuteTime); hBBUw0"
//System.out.print(" now:"+now+"\n"); e8GEoD
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; * iF]n2g:
executeUpdate(); !y@6Mm
} CW,Wx: Y
else{ l\@)y4
+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ::}{_ Z
} s;6CExH
} * /:x sI
} l=v4Fa0^jF
//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 }Nf%n@
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类写好了,下面是在JSP中如下调用。 uLWh|
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<% mD^jd+
CountBean cb=new CountBean(); D?NbW @]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #6CC3TJ'k
CountCache.add(cb); /N&CaH\;^$
out.print(CountCache.list.size()+"<br>"); a+%6B_|\
CountControl c=new CountControl(); /JWGifH
c.run(); ybY]e; v*O
out.print(CountCache.list.size()+"<br>"); ;e1ku|>$
%>