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: ( [K2:n\
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CountBean.java <Gb nPG?
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/* deR$
* CountData.java Ufm(2` FQ
* ~ >&I^4
* Created on 2007年1月1日, 下午4:44 % JgRcx
* Eqz4{\
* To change this template, choose Tools | Options and locate the template under a7XXhsZ
* the Source Creation and Management node. Right-click the template and choose N1D6D$s 0
* Open. You can then make changes to the template in the Source Editor. zz7Y/653
*/ (#fm (@T
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package com.tot.count; d ,h~u{
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/** :t2 9`x
* t(Q&H!~e
* @author XgwMppacw
*/ 4jC4X*
public class CountBean { : ;E7+m
private String countType; 1qB!RIau
int countId; lpM>}0v
/** Creates a new instance of CountData */ ]Ssw32yn
public CountBean() {} PK:o}IWn~x
public void setCountType(String countTypes){ C8bGae(
this.countType=countTypes; [H6X2yjj|
} 0?J|C6XM#4
public void setCountId(int countIds){ kT Z?+hx
this.countId=countIds; +d6Aw}*
} 7G<KrKal
public String getCountType(){ ~x4{P;y
return countType; 'S%} ?#J
}
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public int getCountId(){ 1sIy*z
return countId; [9db=$v8$
} c&| '3i+
} ?$)x$nS`
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CountCache.java %v`-uAy:
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/* "2#-xOCO
* CountCache.java > hDsm;,/
* Oet#wp/I
* Created on 2007年1月1日, 下午5:01
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* azR;*j8Q'
* To change this template, choose Tools | Options and locate the template under niBjq#bJi
* the Source Creation and Management node. Right-click the template and choose (_i
v N
* Open. You can then make changes to the template in the Source Editor. EL 8N[]RF
*/ M<#)D
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package com.tot.count; &0th1-OP_
import java.util.*; Dh!iY0Lz
/** d0H
* \CJx=[3(
* @author ; $ ?jR
c
*/ #^4>U&?
public class CountCache { {l *&l2
public static LinkedList list=new LinkedList(); T$.-{I
/** Creates a new instance of CountCache */ bD-/ZZz
public CountCache() {} |=^#d\?]j
public static void add(CountBean cb){ 53,,%Ue
if(cb!=null){ lEYT{
list.add(cb); @F3-Ugm
} mSk :7ozZ
} Ip7FD9
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} z[|PsC3i:
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CountControl.java <igx[2X
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/* ]\D6;E8P-~
* CountThread.java e??{&[
* A9qO2kq7_
* Created on 2007年1月1日, 下午4:57 "{ry 9?z
* *a4b`HRT
* To change this template, choose Tools | Options and locate the template under mBpsgm:g^
* the Source Creation and Management node. Right-click the template and choose <Z_wDK/UR
* Open. You can then make changes to the template in the Source Editor. Z1V'NJI+
*/ SJ~I
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package com.tot.count; l5y#i7 q
import tot.db.DBUtils; #Z=)=
import java.sql.*; :oj)
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/** wx"6",M
* CN$A-sjZ
* @author @+CSY-g$
*/ 7 NB"oU^h%
public class CountControl{ PRk%C0`
private static long lastExecuteTime=0;//上次更新时间 iq^L~RW5e
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :5cu,&<Gv
/** Creates a new instance of CountThread */ MMA@J
public CountControl() {} > ^v8N
public synchronized void executeUpdate(){ u<y\iZ[
Connection conn=null; w[A3;]la
PreparedStatement ps=null; <<2b2?aS`
try{ B]KLn?zt5
conn = DBUtils.getConnection(); CMG`'gT
conn.setAutoCommit(false); 3JE;:2O~P
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HlL@{<
for(int i=0;i<CountCache.list.size();i++){ /L|}Y242
CountBean cb=(CountBean)CountCache.list.getFirst(); ISnS;
CountCache.list.removeFirst(); vK.4JOlRF
ps.setInt(1, cb.getCountId()); S7~F*CGBh
ps.executeUpdate();⑴ qQ
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//ps.addBatch();⑵ np\Q&
} 5B.??;xtaV
//int [] counts = ps.executeBatch();⑶ e$^!~+J7
conn.commit(); j5Wx*~@(
}catch(Exception e){ i+x6aQ24
e.printStackTrace(); XsN#<"f;i
} finally{ L{0OMyUA
try{ |p4OlUq
if(ps!=null) { _}D?+x,C8
ps.clearParameters(); \HQb#f,
ps.close(); }NBJ T4R
ps=null; KW6" +,Th
} g+/U^JIc4l
}catch(SQLException e){} >(6\ C
DBUtils.closeConnection(conn); )B&<Bk+
} ?{z${ bD
} GK+\-U)v
public long getLast(){ ^oB1 &G
return lastExecuteTime; i |^`gly
} lg
public void run(){ geN%rD
long now = System.currentTimeMillis(); g5 |\G%dOt
if ((now - lastExecuteTime) > executeSep) { 5'-9?-S"
//System.out.print("lastExecuteTime:"+lastExecuteTime); IIn\{*|mW
//System.out.print(" now:"+now+"\n"); }0nB'0|y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3L]^x9Cu)
lastExecuteTime=now; \fR:+rbQ&|
executeUpdate(); h_G7T1;L
} H.[&gm}p>
else{ nW%=k!''
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <r`Jn49
} 5a_!&
} @Be:+01z
} _r|ytQ)
//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 W!B4<'Fjc
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类写好了,下面是在JSP中如下调用。 QIV~)`;
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<% ye7&y4v+
CountBean cb=new CountBean(); y]Tn#4 ,/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); BF[?* b
CountCache.add(cb); P]x+Q
out.print(CountCache.list.size()+"<br>"); ,:4w$!;
CountControl c=new CountControl(); 4H?Ma|,
c.run(); ;1k0o.3
out.print(CountCache.list.size()+"<br>"); J+gsmP-_
%>