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: S[TJ{L(
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CountBean.java %7_c|G1
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/* xELnik_L2
* CountData.java .CrrjS w
* ~)S Q{eK?&
* Created on 2007年1月1日, 下午4:44 pearf2F
* ^jO$nPDd
* To change this template, choose Tools | Options and locate the template under $ljgFmR_
* the Source Creation and Management node. Right-click the template and choose ?|i6]y=D
* Open. You can then make changes to the template in the Source Editor. /f_c?|
*/ J.`z;0]op
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package com.tot.count; ~dIb>[7wy
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/** MuQBn7F{c
* E0 nR Vg
* @author V/0?0VKG
*/ IH$R XGL
public class CountBean { Y:nF.An3
private String countType; ;x[F4d
int countId; ,RkL|'1l
/** Creates a new instance of CountData */ x04JU$@
public CountBean() {} L"i
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public void setCountType(String countTypes){ u5f+%!p
this.countType=countTypes; ~urV`J
} :'OCQ.[{s
public void setCountId(int countIds){ gyW*-:C
this.countId=countIds; @17hB h
} h_ ^,|@C"
public String getCountType(){
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return countType; N*PF&MyB
} 67I6]3[Z
public int getCountId(){ 7k<4/|CQ{
return countId; 6~b~[gA
} )e)@_0
} o:\RJig<
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CountCache.java CI+dIv>
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/* 4>4*4!KR}
* CountCache.java v-85`h
* ILUA'T=B0
* Created on 2007年1月1日, 下午5:01 dqMR<Nl&
* q8:Z.<%8
* To change this template, choose Tools | Options and locate the template under 9T47U; _)
* the Source Creation and Management node. Right-click the template and choose 4#5w^
* Open. You can then make changes to the template in the Source Editor. n9;+RhxA
*/ UarU.~Uqi
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package com.tot.count; p}KZ#"Q
import java.util.*; eSynw$F2N
/** Ae,-.xJ
* &bx;GG\<4
* @author 8wz4KG3SK
*/ %h**L'~``
public class CountCache { H|='|k5Y.
public static LinkedList list=new LinkedList(); 28[dTsd%
/** Creates a new instance of CountCache */ 29"eu#-Qj
public CountCache() {} d{.cIv
public static void add(CountBean cb){ Q6y883>9
if(cb!=null){ c7j^OP
list.add(cb); BoB2q(
} &*
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} &XosDt
} A>6b
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CountControl.java [y
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/* ce{GpmW
* CountThread.java /&=E=S6
* h<.G^c)
* Created on 2007年1月1日, 下午4:57 6Q,-ZM=Z_p
* ND\
* To change this template, choose Tools | Options and locate the template under P>=~\v nN#
* the Source Creation and Management node. Right-click the template and choose =R#K`H66j
* Open. You can then make changes to the template in the Source Editor. Qp7|p
*/ cL&V2I5O
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package com.tot.count; %t0Fx
import tot.db.DBUtils; R@``MC0
import java.sql.*; ?;.j)
/** V *=To
* X75>C<
* @author uROt h_/
*/ tRYMK+
public class CountControl{ >9W ;u`
private static long lastExecuteTime=0;//上次更新时间 . m_y5J
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 L0SeG:
/** Creates a new instance of CountThread */ &I.UEF2,
public CountControl() {} mt7}1s,i[
public synchronized void executeUpdate(){ /%Bc*k=ox
Connection conn=null; sk!v!^\_r
PreparedStatement ps=null; Wy%q9x]}
try{ 9+.0ZP?
conn = DBUtils.getConnection(); B^Q\l!r
conn.setAutoCommit(false); zIWw055W
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); SsDz>PP
for(int i=0;i<CountCache.list.size();i++){ RqW
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CountBean cb=(CountBean)CountCache.list.getFirst(); Q7$ILW-S
CountCache.list.removeFirst(); buGW+TrWY
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ L)VEA8}
//ps.addBatch();⑵ n6;jIf|
} :W,6zv(..u
//int [] counts = ps.executeBatch();⑶ ;]?1i4p)
conn.commit(); In|:6YDL&
}catch(Exception e){ CU 2;m\Hc
e.printStackTrace(); >2`)S{pBD
} finally{ s;q]:+#7g
try{ .]%PnJM9K
if(ps!=null) { JxI}#iA
ps.clearParameters(); ^jb55X}
ps.close(); <3z]d?u
ps=null; EvIL[\Dy
} o:_}=1nh
}catch(SQLException e){} R-J\c+C>W
DBUtils.closeConnection(conn); XJsHy_6
} >e*m8gm#
} %\=5,9A\
public long getLast(){ ZA zn-n
return lastExecuteTime; ^ng#J\
} ,"
public void run(){ ?hvPPEJf
long now = System.currentTimeMillis(); 9_[TYzpB!
if ((now - lastExecuteTime) > executeSep) { c|u{(E58
//System.out.print("lastExecuteTime:"+lastExecuteTime); (E59)z -
//System.out.print(" now:"+now+"\n"); OwV>`BIwns
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -_.)~)P
lastExecuteTime=now; 7+JQaYO`"
executeUpdate(); E#r6e+e1Q%
} 0Psp/H%
else{ R6]/g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); BFt?%E/]
} M4pEwD
} n[lf==R
} Qn(e[
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//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 C_=! ( @`8
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类写好了,下面是在JSP中如下调用。 Bp6jF2
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<% 8s pGDg\g
CountBean cb=new CountBean();
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); x;S v&
CountCache.add(cb); b gGd
out.print(CountCache.list.size()+"<br>"); Bvzl*
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CountControl c=new CountControl(); F"VNz^6laV
c.run(); ibex:W^
out.print(CountCache.list.size()+"<br>"); d*Dq=.F(
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