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: Ej+]^t$\
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CountBean.java \3Q:K|
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/* ^A *]&%(h
* CountData.java {DEzuU
* -7-Fd_F8
* Created on 2007年1月1日, 下午4:44 *Z]5!$UpC
* 7>PF ~=
* To change this template, choose Tools | Options and locate the template under RwAbIXG{0
* the Source Creation and Management node. Right-click the template and choose \~gA+o}Q
* Open. You can then make changes to the template in the Source Editor. 8zQ_xE
*/ %aj7-K6:t
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package com.tot.count; Kk!6B
h1^9tz{
/** |5oKq'(b
* g.[+yzuE6
* @author !
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*/ `e'G.@
public class CountBean { M1AZ}bc0]
private String countType; ~In{lQ[QX
int countId; =cf{f]N
/** Creates a new instance of CountData */ CS~=Z>6EjA
public CountBean() {} [c&2i`C
public void setCountType(String countTypes){ ]j& FbP)3
this.countType=countTypes; +M44XhT
} `pP9z;/Xq
public void setCountId(int countIds){ _MM
this.countId=countIds; `4VO&lRm
} BN+V,W
public String getCountType(){ !Oeq
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return countType; La`h$=#`
} wzD\8_;6N
public int getCountId(){ 2}^+]5
return countId; 9 '2=
} r_4TtP&UW
} wl7 M fyU
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CountCache.java xK$}QZ)
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/* Y.DwtfE
* CountCache.java +VSZhg,Np8
* wENzlXeOP
* Created on 2007年1月1日, 下午5:01 \Os:6U=X-
* s{yJ:WncI
* To change this template, choose Tools | Options and locate the template under WwW"fkv
* the Source Creation and Management node. Right-click the template and choose &g*klt'B
* Open. You can then make changes to the template in the Source Editor. ~k9O5S{
*/ jmkRP"ZnA
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package com.tot.count; q&u$0XmV
import java.util.*; qovQ9O
/** $ I#7dJ"*
* `Jn,IDq
* @author %/P=m-K
*/ 0;}Aj8Fle
public class CountCache { ?sV[MsOsC
public static LinkedList list=new LinkedList(); Kn']n91m
/** Creates a new instance of CountCache */ bX7EO 8
public CountCache() {} Xa4GqV9M/-
public static void add(CountBean cb){ FI\IY
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if(cb!=null){ '4$lL6ly>
list.add(cb); R"NGJu9
} >OT\~C
} LRWOBD
} doLkrEm&
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CountControl.java S2ark,sp6
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/* uii7b7[w
* CountThread.java YZ0en1ly
* Z*9L'd"D|
* Created on 2007年1月1日, 下午4:57 f7Yz>To
* 8fnR1mWG
* To change this template, choose Tools | Options and locate the template under pP3U,n
* the Source Creation and Management node. Right-click the template and choose iu+3,]7Fm
* Open. You can then make changes to the template in the Source Editor. 3a'q`.L
*/ a~WqUL
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package com.tot.count; Po> e kz_E
import tot.db.DBUtils; o"RJ.w:dn
import java.sql.*; T$u~E1
/** 7k `_#
* [ dGO,ndE
* @author "r@G@pe
*/ U M@naU
public class CountControl{ K${}r0
private static long lastExecuteTime=0;//上次更新时间 zyDZ$Dhka
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 T:U4:"
/** Creates a new instance of CountThread */ 2sUbiDe-
public CountControl() {} &RWM<6JP
public synchronized void executeUpdate(){ KCD5*xH
Connection conn=null; D%A@lMru
PreparedStatement ps=null; J2'K?|,m
try{ QskUdzQ=
conn = DBUtils.getConnection(); i (0hvV>'
conn.setAutoCommit(false); BH5w@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); prUHjS
for(int i=0;i<CountCache.list.size();i++){ 85}
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CountBean cb=(CountBean)CountCache.list.getFirst(); 8hZwQ[hr
CountCache.list.removeFirst(); q8/ihA6:
ps.setInt(1, cb.getCountId()); PT+c&5A S
ps.executeUpdate();⑴ <^Nk.E
//ps.addBatch();⑵ R3?:\d{
} )i0 $j)R
//int [] counts = ps.executeBatch();⑶ AQe!Sqg'
conn.commit(); lj*8mS/;h
}catch(Exception e){ l]$40 j
e.printStackTrace(); }%+qP+O\
} finally{ Y[?`\c|
try{ WV2~(/hX&
if(ps!=null) { v{.\iIg N
ps.clearParameters(); O] H=s
ps.close(); _#FIay\ahB
ps=null; p'80d:
} {|XQO'Wg
}catch(SQLException e){} a!D*)z Y
DBUtils.closeConnection(conn); -1CEr_(P^
} ]%Y\ZIS
} WO@H*
public long getLast(){ 8[~~gYl
return lastExecuteTime; {S*!B
} 6Hwxx5>r
public void run(){ _jmkl
B
long now = System.currentTimeMillis(); "7d.i(vw
if ((now - lastExecuteTime) > executeSep) { a1|c2kT
//System.out.print("lastExecuteTime:"+lastExecuteTime); .uKx>YB}
//System.out.print(" now:"+now+"\n"); EI\v
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); =53bLzr
lastExecuteTime=now; .gq(C9<B[
executeUpdate(); LEK/mCL
} 0I
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else{ \yG`Sfu2
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <m0{'xw
} Oqmg;\pm
} U*qNix
} sMm/4AY]
//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 7@IFp~6<qK
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类写好了,下面是在JSP中如下调用。 (]XbPW
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<% thptm
CountBean cb=new CountBean(); } L <,eV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); cOb4c*
CountCache.add(cb); Fu%X
out.print(CountCache.list.size()+"<br>"); :+:6_x
CountControl c=new CountControl(); On&L#pf
c.run(); l4 "\) ];
out.print(CountCache.list.size()+"<br>"); Y208b?=9w
%>