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: j)Z0K$z=
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CountBean.java Bx.hFEL
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/* TJB4N$-}A
* CountData.java eKU4"XTk
* Oi{J}2U
* Created on 2007年1月1日, 下午4:44 K7/&~;ZwT
* `m$,8f%j6_
* To change this template, choose Tools | Options and locate the template under $U(D*0+o/
* the Source Creation and Management node. Right-click the template and choose mxe\+j#
* Open. You can then make changes to the template in the Source Editor. <TSps!(#
*/ !>&G+R+k
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package com.tot.count; Bgai|l
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/** L:Faq1MG
* % 3fpIzm
* @author c;=St1eoz
*/ Ki%)LQAg
public class CountBean { D%=&euB
private String countType; IWwOP{ <ZQ
int countId; r]kks_!Z
/** Creates a new instance of CountData */ .'2"83f
public CountBean() {} S'>KGdF
public void setCountType(String countTypes){ jP<6Q|5F
this.countType=countTypes; TP Y&O{q
} u{dkUG1ia
public void setCountId(int countIds){ A.YK=_J
this.countId=countIds; W&m3"~BJ
} kHQn'r6
public String getCountType(){ {3!A\OR
return countType; &?']EcU5h9
} w[G-=>;
public int getCountId(){ ZT,auSX
return countId; PAVlZ}kj
} Upm#:i|"
} "g(q)u >
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CountCache.java b0tbS[j
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/* CM`Q((
* CountCache.java 0|4R8Dh*-
* j9cB<atL
* Created on 2007年1月1日, 下午5:01 g1B P
* R80|q#h,]
* To change this template, choose Tools | Options and locate the template under QqXaXx;
* the Source Creation and Management node. Right-click the template and choose PC%_^BDW
* Open. You can then make changes to the template in the Source Editor. <YWu/\{KT
*/ ol_&epG;ST
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package com.tot.count; 'OMl9}M
import java.util.*; SO~pe$c-
/** Yt r*"-
* H
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* @author 9mpQusM
*/ >as+#rz1p
public class CountCache { [y<s]C6E
public static LinkedList list=new LinkedList(); <FN+
/** Creates a new instance of CountCache */ ](IOn:MuDE
public CountCache() {} h^J :k
public static void add(CountBean cb){ Exat_ L'?
if(cb!=null){ dE(d'*+a
list.add(cb); p%OVl[^jp
} $=C `V
} g](&H$g
} Af^9WJ
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CountControl.java h@s i)5"
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/* u R!'v
* CountThread.java ux[13]yY
* s2nZW pIy
* Created on 2007年1月1日, 下午4:57 eE{
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* YT@H^=
* To change this template, choose Tools | Options and locate the template under rPHM_fW(O@
* the Source Creation and Management node. Right-click the template and choose -3XnUGK
* Open. You can then make changes to the template in the Source Editor. V0gu0+u~R
*/ W5&KmA
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package com.tot.count; rhN"#?
import tot.db.DBUtils; /]nrxT
import java.sql.*; :[Ie0[H/M
/** #;"lBqxY`
* mUiJ@
* @author (k%r_O 6
*/ pU u')y
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 %\%&1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4&~*;an7
/** Creates a new instance of CountThread */ I*(7(>zgyv
public CountControl() {} >EgMtZ88.<
public synchronized void executeUpdate(){ W7IAW7w8U
Connection conn=null; rE\&FVx
PreparedStatement ps=null; b_@bS<wsF}
try{ F<,"{L
conn = DBUtils.getConnection(); t9_&n.z
conn.setAutoCommit(false); `oE.$~'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); fl*49-d
for(int i=0;i<CountCache.list.size();i++){ Ba
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CountBean cb=(CountBean)CountCache.list.getFirst(); N/E=-&E8
CountCache.list.removeFirst(); ]oC7{OoX
ps.setInt(1, cb.getCountId()); 'qidorT>N
ps.executeUpdate();⑴ wee5Nirw6
//ps.addBatch();⑵ b/=>'2f
} ?;go5f+X
//int [] counts = ps.executeBatch();⑶ 0LP>3"Sm
conn.commit(); r\}
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}catch(Exception e){ /(i~Hpp
e.printStackTrace(); 6%T_;"hb
} finally{ 1oG'm
try{ /j(<rz"j
if(ps!=null) { e#?rK=C?9
ps.clearParameters(); X-%91z:o58
ps.close(); LM".]f!,
ps=null; XJ3aaMh"
} hrbeTtqi
}catch(SQLException e){} yGb^k R}d
DBUtils.closeConnection(conn); )KY U[
} 6 x8lnXtA
} =&vRT;6
public long getLast(){
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return lastExecuteTime; Uz7V2r%]
} ;S+"z;$m
public void run(){ FFf
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long now = System.currentTimeMillis(); d,t'e?
if ((now - lastExecuteTime) > executeSep) { }cg 1CT5
//System.out.print("lastExecuteTime:"+lastExecuteTime); Zb~G&.
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//System.out.print(" now:"+now+"\n"); V}4u1oG
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); cHwN=mg]S
lastExecuteTime=now; Zor Q2>
executeUpdate(); !(N,tZ
} !]!9 $6n
else{ jL~. =QD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8;Df/%
} hx@E,
} W-vEh
} X""}]@B9z
//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 6^nxw>-
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类写好了,下面是在JSP中如下调用。 L4Si0 K
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<% 'S;l"
CountBean cb=new CountBean(); $60]RCu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); iIg99c7/&9
CountCache.add(cb); ?yvjX90
out.print(CountCache.list.size()+"<br>"); cX48?srG
CountControl c=new CountControl(); Z`@< O%
c.run(); Za1VJ5-
out.print(CountCache.list.size()+"<br>"); -O[9{`i]
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