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: S84S/y
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CountBean.java +%Z:k
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/* k+~2
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* CountData.java (,b\"Q
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* Created on 2007年1月1日, 下午4:44 9U Hh#
* *bUOd'vh
* To change this template, choose Tools | Options and locate the template under gyxC)br
* the Source Creation and Management node. Right-click the template and choose p$cb&NNh*H
* Open. You can then make changes to the template in the Source Editor. i!iG7X)qT
*/ "bz]5c~
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package com.tot.count; e@iz`~[
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/** J+}z*/)|#
* oWEzzMRz
* @author m]c1DvQb
*/ B qLL]%F
public class CountBean { 03"FK"2S
private String countType; .@$A~/ YU
int countId; 6W:FT Pt44
/** Creates a new instance of CountData */ 5..YC=_20
public CountBean() {} %!8w)1U
public void setCountType(String countTypes){ i`=%X{9
this.countType=countTypes; 9+ |W;
}
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public void setCountId(int countIds){ I=
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this.countId=countIds; uzhTNf
} H-mQ{K^
public String getCountType(){ ]GD&EQ
return countType; syCT)}T6z
} RwhKW?r+
public int getCountId(){ vOv"^X
return countId; taMcm}*T1
} a)I>Ns)
} pJuD+v
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CountCache.java v#e*RI2}
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/* 1 hD(l6tG@
* CountCache.java gw^W6v
* q*kLi~Oe
* Created on 2007年1月1日, 下午5:01 9FPqd8(]*V
* N#XC%66qy!
* To change this template, choose Tools | Options and locate the template under &MPlSIg
* the Source Creation and Management node. Right-click the template and choose E<7$!P=z`
* Open. You can then make changes to the template in the Source Editor. 9Ais)Wy%p
*/ *$Zy|&[Z
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package com.tot.count; u?F.%j-
import java.util.*; Rtlc&Q.b
/** VP<LY/'f
* D
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* @author _9q byhS7
*/ cp0yr:~
public class CountCache { A4Q{(z-?
public static LinkedList list=new LinkedList(); "=LeHY=9
/** Creates a new instance of CountCache */ KtArV
public CountCache() {} HZ1 nuA
public static void add(CountBean cb){ \:+ NVIN
if(cb!=null){ =woP~+
list.add(cb); <p-@XzyE
} :jC$$oC].
} e X6o7a
} 5.D0 1?k
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CountControl.java 1
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/* HTMg{_r(%
* CountThread.java 7P]i|Q{
* bZ^'_OOn
* Created on 2007年1月1日, 下午4:57 Rt5pl,Nf
* vU(fd!V ?
* To change this template, choose Tools | Options and locate the template under v*c"SI=@M=
* the Source Creation and Management node. Right-click the template and choose '-cayG
* Open. You can then make changes to the template in the Source Editor. hT `&Xb
*/ z?F`)}
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package com.tot.count; I!SIy&=W
import tot.db.DBUtils; wQ[!~>A
import java.sql.*; y]+[o1]-c
/** fRq+pUxU
* 0A-yQzL|
* @author 1_l)$"
*/ pF9WKpzE
public class CountControl{ 6/ T/A+u
private static long lastExecuteTime=0;//上次更新时间 P&<NcOCL&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Onou:kmf1
/** Creates a new instance of CountThread */ $s-B
public CountControl() {} v`G}sgn
public synchronized void executeUpdate(){ t=|}?lN<
Connection conn=null; A/"2a55
PreparedStatement ps=null; 'St?nW3
try{ |_QpB?b
conn = DBUtils.getConnection(); d1D=R8P_u
conn.setAutoCommit(false); qq3/K9 #y
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?%#no{9
for(int i=0;i<CountCache.list.size();i++){ 6q!Q([D_
CountBean cb=(CountBean)CountCache.list.getFirst(); o6:bmKWE
CountCache.list.removeFirst(); ] SLeWs
ps.setInt(1, cb.getCountId()); [:qJ1^U U
ps.executeUpdate();⑴ f6nuh&!-
//ps.addBatch();⑵ RGkV%u^
} .J8 gW
//int [] counts = ps.executeBatch();⑶ 0AF,} &$
conn.commit(); TBky+]p@
}catch(Exception e){ ` N
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e.printStackTrace(); Q7{{r&|t&
} finally{ +$#XV@@~
try{ aof'shS8
if(ps!=null) { mN .
ps.clearParameters(); S)W?W}*R\
ps.close(); xg 8R>j
ps=null; :RwURv+kT
} hwQ|'^(@O
}catch(SQLException e){} ]6s/y
DBUtils.closeConnection(conn); W]_a_5
}
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} l*huKSX}
public long getLast(){ NU+PG`Vb
return lastExecuteTime; y>#kT
} X.FoX
public void run(){ ~4O3~Y_+GN
long now = System.currentTimeMillis(); _HjB'XNr(
if ((now - lastExecuteTime) > executeSep) { SuNc&e#(
//System.out.print("lastExecuteTime:"+lastExecuteTime); _MuzD&^qE
//System.out.print(" now:"+now+"\n"); uXvE>VpJG
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); GN=8;Kq%
lastExecuteTime=now; R y(<6u0
executeUpdate(); B&<5VjZ\
} MgN;[4|[h
else{ >[wB|V5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,?IXfJ`c
} G2 V$8lh
} p#-=mXE/2
} mAY/J0_
//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 >j*0fb!:]
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类写好了,下面是在JSP中如下调用。 rdtzz#7
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<% g1_z=(i`Z
CountBean cb=new CountBean();
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .Cs'@[Ciy
CountCache.add(cb); .IVKgQ
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out.print(CountCache.list.size()+"<br>"); J><hrZ
CountControl c=new CountControl(); x]?V*Jz
c.run(); <eP,/H
out.print(CountCache.list.size()+"<br>"); Uovna:"
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