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:
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CountBean.java 2H9;4>ss
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/* ?Rd{`5.D
* CountData.java VdOcKP.
* ; S~
* Created on 2007年1月1日, 下午4:44 oY<R[NYKu
* '`sZo1x%f
* To change this template, choose Tools | Options and locate the template under [I6&|Lz>
* the Source Creation and Management node. Right-click the template and choose nsN|[E8
* Open. You can then make changes to the template in the Source Editor. &rfl(&\oUi
*/ ;hb_jW-0W
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package com.tot.count; <5E: ,<
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/** RAU"
* A+41JMH
* @author x%RG>),U
*/ uW0D m#
public class CountBean { d}^G790
private String countType; W|CZA
int countId; W,fXHYst
/** Creates a new instance of CountData */ ?aWMU?S
public CountBean() {} TGH"OXV*@
public void setCountType(String countTypes){ "ph<V,lg
this.countType=countTypes; !g7lJ\B
} 1LVO0lT
public void setCountId(int countIds){ zff<#yK1
this.countId=countIds; QWI)Y:<K/
} vf;&0j&`
public String getCountType(){ bae\EaS
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return countType; \e9rXh%
} svvl`|n%
public int getCountId(){ M2!2J
return countId; y8j6ttQv=t
} RdqB^>X
} ac!!1lwA
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CountCache.java N;S1s0FN
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/* g[Q+DT
* CountCache.java DH Qs_8Df
* <j}A=SDZ)
* Created on 2007年1月1日, 下午5:01 He*c=^8k
* 3|(<]@
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* To change this template, choose Tools | Options and locate the template under #HTq\J!
* the Source Creation and Management node. Right-click the template and choose YY4q99^K
* Open. You can then make changes to the template in the Source Editor. YkSHJ{>
*/ x@3"
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package com.tot.count; ;6M [d
import java.util.*; z\`tnz7>$
/** lWakyCS
* {I8C&GS
* @author |8?DQhd}
*/ x|$|~6f=n
public class CountCache { X/ lmj_v
public static LinkedList list=new LinkedList(); tID=I0D
/** Creates a new instance of CountCache */ "\+.S]~
public CountCache() {} C7FxV2
public static void add(CountBean cb){ T^icoX=c4
if(cb!=null){ nc^DFP
list.add(cb); +_1sFH`
} :i>If:>g
} hgK
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} =Q*x=}NH
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CountControl.java 0.[tEnLZ
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/* rXR!jZ.hi
* CountThread.java g OK
* \Oxyc}&
* Created on 2007年1月1日, 下午4:57 d:pGdr& .
* H[RX~Xk2E
* To change this template, choose Tools | Options and locate the template under 8a3EVc
* the Source Creation and Management node. Right-click the template and choose Ka y\;fXT
* Open. You can then make changes to the template in the Source Editor. K3k{q90
*/ h [@}}6
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package com.tot.count; s:3b. *t<
import tot.db.DBUtils; !Ahxi);a
import java.sql.*; NfWL3"&X
/** 8Si3
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* )=VAEQhL-
* @author Ab6R ?mUM
*/ (H8JV1J
public class CountControl{ i1ScXKO
private static long lastExecuteTime=0;//上次更新时间 NFyKTA6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 GOOm] ]I
/** Creates a new instance of CountThread */ {y'4&vt<~
public CountControl() {} ey6ujV7!
public synchronized void executeUpdate(){ [RF 6mWQ
Connection conn=null; ~jzjJ&O&
PreparedStatement ps=null; V8Ri2&|3
try{ c \;_jg
conn = DBUtils.getConnection(); 1obajN
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^YJ%^P
for(int i=0;i<CountCache.list.size();i++){ Z~].v._YV)
CountBean cb=(CountBean)CountCache.list.getFirst(); pI_dV44W
CountCache.list.removeFirst(); L{rd',
ps.setInt(1, cb.getCountId()); L2=:Nac
ps.executeUpdate();⑴ #{?~XS
//ps.addBatch();⑵ fejC,H4I
} JvK]EwR
;
//int [] counts = ps.executeBatch();⑶ ;W]9DBAB
conn.commit(); [+_>g4M~%
}catch(Exception e){ a`R_}nus*
e.printStackTrace(); ]tzF
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} finally{ CXi[$nF3
try{ bjo}95
if(ps!=null) { Nz}PcWF/
ps.clearParameters(); d^f rKPB
ps.close();
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ps=null; TbaZFLr
} &isKU8n
}catch(SQLException e){} SgYMPBh
DBUtils.closeConnection(conn); }'*6 A
} d&\3}uH
} Z&79: 9=#>
public long getLast(){ K:^0*5Y-k
return lastExecuteTime; Tw7]
} 0?}n( f!S
public void run(){ YN+vk}8 <
long now = System.currentTimeMillis(); B%tWi
if ((now - lastExecuteTime) > executeSep) { tHAe
//System.out.print("lastExecuteTime:"+lastExecuteTime); U
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//System.out.print(" now:"+now+"\n"); ~>HzAo9e
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); R8_I ASs
lastExecuteTime=now; lj UdsU w
executeUpdate(); u`&lTJgF/O
} `<7!Rh,tS^
else{ u88wSe<\X
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !?v_.
} !LzA
} !sSq 4K
} :PtZKt;~X
//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 r fzNw
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类写好了,下面是在JSP中如下调用。 1`YU9?
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<% |q58XwU `
CountBean cb=new CountBean(); </WeB3#6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xDGS`o_w_
CountCache.add(cb); Fs].Fa
out.print(CountCache.list.size()+"<br>"); TN1pg
CountControl c=new CountControl(); N0.|Mb"?t
c.run(); 4l+!Z, b
out.print(CountCache.list.size()+"<br>"); R(`:~@3\6
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