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: }y9mNT
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CountBean.java Ag F,aZU
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/* 3%.#}O,(
* CountData.java /dv<qp
* U|g:`v7
* Created on 2007年1月1日, 下午4:44 v3v[[96p
* A^q[N
* To change this template, choose Tools | Options and locate the template under Q#nOJ(KV
* the Source Creation and Management node. Right-click the template and choose nLV9<M
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* Open. You can then make changes to the template in the Source Editor. BD`2l!d
*/ R(n^)^?
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package com.tot.count; <7-J0btV
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/** +la2n(CAK
* B'^:'uG
* @author KiJT!moB
*/ *
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public class CountBean { SPp#f~%m
private String countType; `'V4PUe
int countId; Ug&,Y/tFw2
/** Creates a new instance of CountData */ 'Ysx=
public CountBean() {} Y(44pA&oN
public void setCountType(String countTypes){ ` AY_2>7
this.countType=countTypes; qIld;v8w"g
} @:KJYm[
public void setCountId(int countIds){ }#X8@
this.countId=countIds; ?. D3'qv
} xhRngHU\z<
public String getCountType(){ 7EXI6jGJ|
return countType; gks{\ H]
} sP ls
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public int getCountId(){ -&<Whhs.@
return countId; ?wO-cnl
} h[PYP5{L
} ,Jd
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CountCache.java o`Ta("9^
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/* q`pP$i:
* CountCache.java ZcaX'5}!S
* Ek6MYc8<b~
* Created on 2007年1月1日, 下午5:01 }Q";aU0^
* HeG)/W?r
* To change this template, choose Tools | Options and locate the template under :rg5Kt&
* the Source Creation and Management node. Right-click the template and choose -=(!g&0
* Open. You can then make changes to the template in the Source Editor. X=>=5'
*/ x:QgjK
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package com.tot.count; *W
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import java.util.*; AZmb!}m+d
/** L:z?Zt)|
* 8H_l:Z [:i
* @author ;6!Pwb;hY
*/ 9k 6r_G"
public class CountCache { .j-IX1Sa
public static LinkedList list=new LinkedList(); eQ&ZX3*}
/** Creates a new instance of CountCache */ P><o,s"v
public CountCache() {} (<)]sp2
public static void add(CountBean cb){ !&"<oPjr+
if(cb!=null){ PK"c4>q
list.add(cb); RoyPrO [3
} fXc m|U,ho
} 65Cg]Dt71
} T8HF|%I
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CountControl.java ,%)6jYHR w
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/* ' Tc]KXD6
* CountThread.java {\(L%\sV@
* rp0ZvEX
* Created on 2007年1月1日, 下午4:57 TsGE cxIg
* 7R\oj8[
* To change this template, choose Tools | Options and locate the template under zA1lca0HK
* the Source Creation and Management node. Right-click the template and choose AU$Uxwz4
* Open. You can then make changes to the template in the Source Editor. rW0FA
*/ _-#'j2
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package com.tot.count; +mp@b942*
import tot.db.DBUtils; PoT`}-9
import java.sql.*; QI3Nc8t_2
/** z5r$M
* Ck!VV2U#
* @author /<]{KI
*/ Lg+G; W
public class CountControl{ sUU{fNC6|
private static long lastExecuteTime=0;//上次更新时间 R<=zCE `:
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !H}vu]R
/** Creates a new instance of CountThread */ rhb@FE)Mc
public CountControl() {} <0PT"ij
public synchronized void executeUpdate(){ q@xBJ[IM
Connection conn=null; f?'JAC*
PreparedStatement ps=null; zBe8,, e
try{ -k7X:!>QHC
conn = DBUtils.getConnection(); jr`Es s
conn.setAutoCommit(false); 59Gk3frk(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 3yNU$.g
for(int i=0;i<CountCache.list.size();i++){ g=e71DXG2
CountBean cb=(CountBean)CountCache.list.getFirst(); d%0~c'D8a
CountCache.list.removeFirst(); nO)X!dp}J
ps.setInt(1, cb.getCountId()); ~D |5u\D-
ps.executeUpdate();⑴ wGZR31
//ps.addBatch();⑵ %.z,+Zz?
} 6AWKLFMV
//int [] counts = ps.executeBatch();⑶ U.@*`Fg
conn.commit(); 8dlw-Q'S
}catch(Exception e){ }`NU@O#
e.printStackTrace(); )<xypDQ
} finally{ +nT'I!//
try{ _Um d
if(ps!=null) { jU5 }\oP@
ps.clearParameters(); 5IbJ
ps.close(); &V)6!,rb
ps=null; /QEiMrz@6
} Ve/xnn]'
}catch(SQLException e){} aBzszp]l+
DBUtils.closeConnection(conn); =GXu 5 8
} g5q$A9.Jl
} MJ\ eh>v&
public long getLast(){ >dM8aJzC
return lastExecuteTime; Ea(,aVlj
} YQ0)5 }
public void run(){ h},oF!,
long now = System.currentTimeMillis(); SI6B#u-i
if ((now - lastExecuteTime) > executeSep) { :h1pBEiH
//System.out.print("lastExecuteTime:"+lastExecuteTime); k;5P om
//System.out.print(" now:"+now+"\n"); j.:h5Y^N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :ZDMNhUl
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lastExecuteTime=now; |0z;K:5s
executeUpdate(); hwqbi "o
}
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else{ j:bgR8%e
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $M:3 XAN
} 7zTqNnPnf
} HWm#t./
} n$(p-po
//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 gip/(/NX
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类写好了,下面是在JSP中如下调用。 [= "r<W0
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<% J`*iZvW#Bx
CountBean cb=new CountBean(); lHB) b}7E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); A*tKF&U5
CountCache.add(cb); F%rHU5CkV
out.print(CountCache.list.size()+"<br>"); ir3VTqz
CountControl c=new CountControl(); +!0eu>~_&
c.run(); =xianQ<lK
out.print(CountCache.list.size()+"<br>"); ,DnYtIERo
%>