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: m[u
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CountBean.java Hca)5$yL
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/* I|$_[Sw
* CountData.java [H)p#x
* \9BIRY`
* Created on 2007年1月1日, 下午4:44 _hLM\L
* 'u.`!w '|L
* To change this template, choose Tools | Options and locate the template under b_=k"d
* the Source Creation and Management node. Right-click the template and choose S?=2GY
* Open. You can then make changes to the template in the Source Editor. uoKC+8GA
*/ aARm nV
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package com.tot.count; 8DLMxG
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/** ]?Ru~N}
* *pvhkJ g(
* @author sM~|}|p
*/ FUm-Fp
public class CountBean { )f'cy@b
private String countType; i@_|18F]`
int countId; M ~!*PCd5
/** Creates a new instance of CountData */ (F7!&] 8%
public CountBean() {} J74nAC%J^
public void setCountType(String countTypes){ crC];LMl/
this.countType=countTypes; ZWVcCa3
} /gHRJ$2|Sx
public void setCountId(int countIds){ TZZqV8
this.countId=countIds; w>rglm&
} f.'o4HSj
public String getCountType(){ ./ib{ @A.
return countType; ^QV;[ha,o
} `pN]Ykt
public int getCountId(){ W~Mj6c~S"
return countId; K)0 6][,
} jvm
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} ipKkz
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CountCache.java W?R$+~G
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/* P[ KJuc
* CountCache.java 8N8B${X
*
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* Created on 2007年1月1日, 下午5:01 r0j:ll d
* *RM#F!A
* To change this template, choose Tools | Options and locate the template under K |Yr
* the Source Creation and Management node. Right-click the template and choose m&|?mTo>m
* Open. You can then make changes to the template in the Source Editor. Q.6pmaXrb
*/ Ctt{j'-[
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package com.tot.count; g[@]OsX
import java.util.*; Mk[_yqoCO
/** #\4uu
* NP^kbF
* @author ;][1_
*/
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public class CountCache { ~Cj+6CrT
public static LinkedList list=new LinkedList(); #.tF&$ik
/** Creates a new instance of CountCache */ '1r:z, o|
public CountCache() {} xb_35'$M
public static void add(CountBean cb){ K$'
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if(cb!=null){ tp*AA@~
list.add(cb); $+[HJ{
} )n|:9hc
} HcQ{ok9u
} ~"}-cl,
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CountControl.java c+|,2e
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/* zc,fJM
* CountThread.java R0\E?9P
* Yw+_( 2
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* Created on 2007年1月1日, 下午4:57 {n%F^ky+7
* Ql\{^s+
* To change this template, choose Tools | Options and locate the template under cKK 1$x
* the Source Creation and Management node. Right-click the template and choose 2f I?P
* Open. You can then make changes to the template in the Source Editor. 'ei9* 4y
*/ M*+_E8Lh
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package com.tot.count; Sjj &n S
import tot.db.DBUtils; #xE"];
import java.sql.*; yZA}WTGe
/** (h|l$OL/
* |{Z?a^-NJ
* @author PGu6hV{
*/ =}U`q3k
public class CountControl{ M.!U;U<?
private static long lastExecuteTime=0;//上次更新时间 kY4riZnm
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ep,kImT
/** Creates a new instance of CountThread */ ~++y4NB8Q
public CountControl() {} H-0A&oG
public synchronized void executeUpdate(){ Cq/*/jBM
Connection conn=null; 0rA&_K[#-<
PreparedStatement ps=null; s'fHhG6
try{
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conn = DBUtils.getConnection(); R^fVwDl\
conn.setAutoCommit(false); ) <^9`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (+bk +0
for(int i=0;i<CountCache.list.size();i++){ U{n
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CountBean cb=(CountBean)CountCache.list.getFirst(); ~ N_\V
CountCache.list.removeFirst(); D`r:`
ps.setInt(1, cb.getCountId()); [ZOo%"M_Y
ps.executeUpdate();⑴ <q%buyQna
//ps.addBatch();⑵ d5+ (@HSR
} . v0 .wG
//int [] counts = ps.executeBatch();⑶ RP z0WP
conn.commit(); SgFyv<6>:
}catch(Exception e){ Y-@K@Zu]?
e.printStackTrace(); p?=rQte([
} finally{ % nP13V]
try{ KS1Z&~4
if(ps!=null) { LYkW2h`JQ
ps.clearParameters(); *w59BO&M4
ps.close(); 0b~5i-zM/
ps=null; Y*B}^!k6
} Iz!Blk
}catch(SQLException e){} E,u@,= j
DBUtils.closeConnection(conn); L5of(gQ5]
} \BbemCPAm
} "f(iQI
public long getLast(){ z';p275
return lastExecuteTime; D*DCMMp=0
} !ZD[ $lt+
public void run(){ n4qj"xQ
long now = System.currentTimeMillis(); .& B_\*
if ((now - lastExecuteTime) > executeSep) { %{5mkO&,2
//System.out.print("lastExecuteTime:"+lastExecuteTime); FSIV\ u
//System.out.print(" now:"+now+"\n"); d1 D{wZ3g
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); RAR"9 N
.
lastExecuteTime=now; 9eH(FB
executeUpdate(); 6|rqsk
} b;Pqq@P|g
else{ H)G ^ Y1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,cYU
} D#1'#di*t
} <<@$0RW
} /Rb`^n#
//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 DL_2%&k/
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类写好了,下面是在JSP中如下调用。 sr
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<% FG38) /
CountBean cb=new CountBean(); h~urZXD<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); aYkm]w;C
CountCache.add(cb); '|G_C%,B
out.print(CountCache.list.size()+"<br>"); o2@8w[r
CountControl c=new CountControl(); O (<Wn-
c.run(); _}EGk4E
out.print(CountCache.list.size()+"<br>"); "+[:\
%>