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: W)LtnD2 w
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CountBean.java E9N.b.Q)
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/* -|cB7P
* CountData.java c{(4s6D
* Bk
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* Created on 2007年1月1日, 下午4:44 ^`*p;&(K\^
* 'Dx_n7&=
* To change this template, choose Tools | Options and locate the template under hLo'q^mGr
* the Source Creation and Management node. Right-click the template and choose B[IqLD'6
* Open. You can then make changes to the template in the Source Editor. Z*Lv!6WS
*/ o0&pSCK
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package com.tot.count; SbYsa
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/** +)<H,?/
* .}*_NU
* @author +Rq7m]
*/ "k>;K,:
public class CountBean { X/AA8QV o
private String countType; 3:B4;
int countId; %CaF-m=Pq
/** Creates a new instance of CountData */ u.!<)VIJx
public CountBean() {} ^v+7IFn
public void setCountType(String countTypes){ *Q`y'6S
this.countType=countTypes; d@QC[$qXj
} d{FD.eI0
public void setCountId(int countIds){ gZ 6Hj62D
this.countId=countIds; ,!I'0x1OR
} r>kDRIHB
public String getCountType(){ i-W!`1LH'
return countType; IzWS6!zKU
} oc0z1u
public int getCountId(){ LVAnZ'h/|
return countId; JANP_b:t
} XJ*W7HD
} OE8H |?%
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CountCache.java k<.VR"I
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/* no
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* CountCache.java R1j)0b6cQ%
* R2B0?fu
* Created on 2007年1月1日, 下午5:01 =>u9k:('9
* ];7/DM#Np
* To change this template, choose Tools | Options and locate the template under X)^&5;\`
* the Source Creation and Management node. Right-click the template and choose \CK f/:"
* Open. You can then make changes to the template in the Source Editor. MU#$tXmnC
*/ \+I+Lrj%
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package com.tot.count; $8t\|O3
import java.util.*; Q%Y rm
/** PTf.(B"z
* kFZjMchm A
* @author zrazFI0G
*/ 'boAv%1_sa
public class CountCache { nv-_\M
public static LinkedList list=new LinkedList(); +jrMvk"
/** Creates a new instance of CountCache */ c
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public CountCache() {} YA'_Ba(v)
public static void add(CountBean cb){ `mo>~c7
if(cb!=null){ mj^]e/s%
list.add(cb); w@Gk#
} .:?cU#.
} 6H:'_|G
} +f]\>{o4
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CountControl.java ]>'yt #]
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/* B_uAa5'
* CountThread.java EC0M0qQ
* u4,b%h.
* Created on 2007年1月1日, 下午4:57 @"$rR+r'
* ^{(i;IVG
* To change this template, choose Tools | Options and locate the template under 5^GFN*poig
* the Source Creation and Management node. Right-click the template and choose !tr
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* Open. You can then make changes to the template in the Source Editor. .0H!B#9
*/ F)Qj<6
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package com.tot.count; O,A}p:Pgs
import tot.db.DBUtils; 7J$5dFV2
import java.sql.*; wG2-,\:
/** 0Q= o"@
* GK.U_` 4?
* @author QnPgp(d<
*/ MI<XLn!*
public class CountControl{ z6
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private static long lastExecuteTime=0;//上次更新时间 nbM7 >tnsk
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 f8X/kz
/** Creates a new instance of CountThread */ YkqauyV^
public CountControl() {} @Tl!A1y?
public synchronized void executeUpdate(){ GP,xGZZ
Connection conn=null; eV x
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PreparedStatement ps=null; #Ies
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try{ y9'F D5\s
conn = DBUtils.getConnection(); Q`4]\)Dp
conn.setAutoCommit(false); !YJ^BI
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /qalj\ud
for(int i=0;i<CountCache.list.size();i++){ nM,5KHU4a
CountBean cb=(CountBean)CountCache.list.getFirst(); DZ9qIc}Y
CountCache.list.removeFirst(); TV&4m5
ps.setInt(1, cb.getCountId()); D_MNF=7
ps.executeUpdate();⑴ O&c~7tM%
//ps.addBatch();⑵ avI
} @N0(%o&
//int [] counts = ps.executeBatch();⑶ {x8UL7{
conn.commit(); `+go|
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}catch(Exception e){ Q8sCI An{
e.printStackTrace(); GP/Gv
} finally{ ;zl/
try{ 1>1ii
if(ps!=null) { _Mis-K:]{?
ps.clearParameters(); .Iret:
ps.close(); !agtgS$qII
ps=null; 8;r7ksE~
} gUq)M
}catch(SQLException e){} {=K u9\
DBUtils.closeConnection(conn); x#
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} A t#'q>Dn
} rH<iUiA?O
public long getLast(){ $CYB&|d
return lastExecuteTime; 8(Y=MW;g
} m#oZu {
public void run(){ I;!zZ.\
long now = System.currentTimeMillis(); }M I9?\"q
if ((now - lastExecuteTime) > executeSep) { 6$JRV
//System.out.print("lastExecuteTime:"+lastExecuteTime); `xO&!DN
//System.out.print(" now:"+now+"\n"); :8<\]}J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); U.@j!UrZ
lastExecuteTime=now; yfD)|lK
executeUpdate(); D(]])4
} N>A*N,+
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /N>bEr4w
} bof{R{3q
} cP~?Iz8nD
} 1jhGshhp
//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 1K ;i/
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类写好了,下面是在JSP中如下调用。 1wqsGad+;
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<% q&- A}]
CountBean cb=new CountBean(); 0*.>
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :K)=Hf2y
CountCache.add(cb); Dl#%tYL+3h
out.print(CountCache.list.size()+"<br>"); w C0fPPeA
CountControl c=new CountControl(); B!hrr
c.run(); w]{NaNIeq1
out.print(CountCache.list.size()+"<br>"); }0({c~z\
%>