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: I/u'bDq
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CountBean.java >&*6Fqd
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/* LBW.*PHW
* CountData.java z~GVvgd
* e_YW~z=6t
* Created on 2007年1月1日, 下午4:44 ]R97n|s_
*
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* To change this template, choose Tools | Options and locate the template under %{N>c:2I$
* the Source Creation and Management node. Right-click the template and choose Rh!L'?C
* Open. You can then make changes to the template in the Source Editor. emGV]A%nss
*/ ;:v]NZtc
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package com.tot.count; 6 lB{Ao?|
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/** Q3 K;kS
* ~5-~q0Ge
* @author pP?<[ql[w
*/ *5ka.=Qs
public class CountBean { @C!JtgO%
private String countType; }`+O$0A
int countId; dL1~]Z
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/** Creates a new instance of CountData */ _Ym&UY.u#
public CountBean() {} >VpP/Qf
public void setCountType(String countTypes){ ^G]KE8
this.countType=countTypes; M>`?m
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} DR.3
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public void setCountId(int countIds){ nEjo,
this.countId=countIds; Z\ "Kd
} 3MS3O.0]/
public String getCountType(){ j<.
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return countType; @t{{Q1
} yVbg,q'?
public int getCountId(){ @ef//G+Z"
return countId; |NphG|
} ;`X`c
} J>,'P^
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CountCache.java gJWlWVeq$
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/* (H|%?F;{l
* CountCache.java VWnu#_(
* 8eg2o$k_,#
* Created on 2007年1月1日, 下午5:01 F9>(W#aC
* lW{I`r\]
* To change this template, choose Tools | Options and locate the template under *so6]+)cU
* the Source Creation and Management node. Right-click the template and choose X m_Ub>N5
* Open. You can then make changes to the template in the Source Editor. -ucz+{
*/ <MI$Nl
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package com.tot.count; |THkS@Br
import java.util.*; @j)f(Zlu#
/** /NPl2\ o.
*
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* @author E-*>f"<h
*/ *g/I&'^
public class CountCache { ND)M3qp2(
public static LinkedList list=new LinkedList(); I(iGs I
/** Creates a new instance of CountCache */ i]hR7g<
public CountCache() {} =CD:.FG.
public static void add(CountBean cb){ A;/Xt
if(cb!=null){ ;iwD/=Y
list.add(cb); LN,$P
} Zp% ""
} 4nVO.Ud0$X
} V!yp@%D
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CountControl.java Q@3ld6y
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/* Z.cG`Km*
* CountThread.java #U6/@l)
* 93zlfLS0
* Created on 2007年1月1日, 下午4:57 DI2S
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* DcFV^8O&
* To change this template, choose Tools | Options and locate the template under .q'FSEkMJ
* the Source Creation and Management node. Right-click the template and choose h:US]ZC^Z
* Open. You can then make changes to the template in the Source Editor. K2vPj|
*/ !'6J;Fb#
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package com.tot.count; $yR{ZFo
import tot.db.DBUtils; @eG#%6">
import java.sql.*; X~<>K/}u5
/** 6w .iEb
* ] BP^.N=
* @author !Cv<>_N).
*/ [8om9 Z3
public class CountControl{ BhhK| U/
private static long lastExecuteTime=0;//上次更新时间 .[eSKtbc)
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 FHnHhB [
/** Creates a new instance of CountThread */ SbQ{ >
public CountControl() {} ni 02N3R
public synchronized void executeUpdate(){ lzQ&)7`
Connection conn=null; f R{WS:Pv
PreparedStatement ps=null; MZhJ,km)
try{ * Kp ^al
conn = DBUtils.getConnection(); <T=o]M$
conn.setAutoCommit(false); sVZ}nq{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ 6=[ PJM
CountBean cb=(CountBean)CountCache.list.getFirst(); (t]R#2{
CountCache.list.removeFirst(); '
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ps.setInt(1, cb.getCountId()); '&o>
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ps.executeUpdate();⑴ ]>]H:NEq
//ps.addBatch();⑵ ;Vtpq3
} `(w kqa
//int [] counts = ps.executeBatch();⑶ %CfTqbB
conn.commit(); lfI7&d*
}catch(Exception e){ p_kTLNZd9
e.printStackTrace(); 9BgQoK@
} finally{ rqG6Ll`=+
try{ 7zOvoQ}
if(ps!=null) { U]R|ej
ps.clearParameters();
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ps.close(); Lh5+fk~i~8
ps=null; WY ^K7U
} BfO}4
}catch(SQLException e){} :Q%yW%St$
DBUtils.closeConnection(conn); )="g?E3
} gs2&0rnOy\
} &`9bGO
public long getLast(){ C J}4V!;|
return lastExecuteTime; =*O9)$b
} 70 DQ/b
public void run(){ j(2tbWg9-
long now = System.currentTimeMillis(); oU{-B$w
if ((now - lastExecuteTime) > executeSep) { 8i+jFSZ$
//System.out.print("lastExecuteTime:"+lastExecuteTime); C ^ k3* N
//System.out.print(" now:"+now+"\n"); v(WL 3[y;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); u>-uRz<)t
lastExecuteTime=now; rBL_]\$7}
executeUpdate(); D/!G]hx
} :O2v0Kx
else{ \?Oa}&k$F8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {N8rZ [Oo
} U S~JLJI
} JO;`Kz_$
} U1@P/
//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 d`rDEa
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类写好了,下面是在JSP中如下调用。 m:o$|7r
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<% z@40g)R2A
CountBean cb=new CountBean(); SZ1pf#w!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); sRI=TE]s
CountCache.add(cb); 4?6'~G$k
out.print(CountCache.list.size()+"<br>"); \}_7^)S;
CountControl c=new CountControl(); L``mF(R^
c.run(); =dJEcC_J
out.print(CountCache.list.size()+"<br>"); Mdq'> <ajL
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