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: ]M;! ])b$
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CountBean.java krc!BK`V
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/* -74T C
* CountData.java >/bK?yT<
* DjvgKy=Jr_
* Created on 2007年1月1日, 下午4:44 B)8Hj).@B
* vI}S6-"<
* To change this template, choose Tools | Options and locate the template under k]pD3.QJ
* the Source Creation and Management node. Right-click the template and choose ;jI"|v{vnS
* Open. You can then make changes to the template in the Source Editor. "\?G
*/ y: [] +
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package com.tot.count; ZNeqsN{
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/** pUG fm
* C/VYu-p%
* @author *?Ef}:]
*/ N)WG~=Gi
public class CountBean { X(28xbd|
private String countType; ;NeEgqW"
int countId; 1G.gPx[
/** Creates a new instance of CountData */ ?ovGYzUZ
public CountBean() {} 1:UC\ WW
public void setCountType(String countTypes){ JZxF)]^
this.countType=countTypes;
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} F*:NKT d
public void setCountId(int countIds){ I.1l
this.countId=countIds; 5zna?(#}
} J5( D7rp#
public String getCountType(){ @rE)xco
return countType; Uy|=A7Ad
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}
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public int getCountId(){ 6FMW g:{
return countId; @6'E8NFl
} IkNt!
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} tN> B$sv
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CountCache.java T<k1?h^7
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/* vaJXX
* CountCache.java h]$?~YE
* dU3>h[q
* Created on 2007年1月1日, 下午5:01 &novkkqY
* {bqKb=nyZ
* To change this template, choose Tools | Options and locate the template under x]cZm^
* the Source Creation and Management node. Right-click the template and choose 8lSn*;S,
* Open. You can then make changes to the template in the Source Editor. /C2f;h(1
*/ WTs[Sud/
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package com.tot.count; \&)W#8V
import java.util.*; #gJ~ {tA:
/** lNVAKwW2#
* l5]oS?>y
* @author Er1u1@
*/ NVWeJ+w
public class CountCache { bMOM`At>z
public static LinkedList list=new LinkedList(); |hQ|'VCN
/** Creates a new instance of CountCache */ HKN"$(Q
public CountCache() {} qpqz. {\
public static void add(CountBean cb){ 7qK0!fk5
if(cb!=null){ k|Yv8+XT
list.add(cb); E?4@C"Na
} Mr,y|
} <;E[)tv
} m{dyVE
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CountControl.java ^J~A+CEf"W
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/* ?iEXFYJG
* CountThread.java dN/ "1%9)
* l~!fQ$~
* Created on 2007年1月1日, 下午4:57 C!k9 JAa$Z
* rnv7L^9^A
* To change this template, choose Tools | Options and locate the template under b\j&!_
* the Source Creation and Management node. Right-click the template and choose L(2P|{C
* Open. You can then make changes to the template in the Source Editor. VN-#R=D
*/ aevG<|qP
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package com.tot.count; bNpIC/#0K
import tot.db.DBUtils; 'L|GClc6)
import java.sql.*; S*m`'
/** ^~<Rz q!
* RzJ}C T
* @author p6y0W`U
*/ qTh='~m4[
public class CountControl{ ka)LK@p6
private static long lastExecuteTime=0;//上次更新时间 eGe[sv"k
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6 #x)W
/** Creates a new instance of CountThread */ K[>@'P}y
public CountControl() {} UtBlP+bE?y
public synchronized void executeUpdate(){ i,Wm{+H-O
Connection conn=null; 3s_k>cO=
PreparedStatement ps=null; Q}?N4kg
try{ Xm=^\K3
conn = DBUtils.getConnection(); f,HzrHax
conn.setAutoCommit(false); io r [v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?}3PJVy?
for(int i=0;i<CountCache.list.size();i++){ m{$tO;c/Q
CountBean cb=(CountBean)CountCache.list.getFirst(); %3c|
CountCache.list.removeFirst(); H(G^O&ppdB
ps.setInt(1, cb.getCountId()); ~d7Wjn$@
ps.executeUpdate();⑴ bqQO E4;
//ps.addBatch();⑵ { .3
} @Gn?8Ur%
//int [] counts = ps.executeBatch();⑶ VXc+Wm*W
conn.commit(); j*La,iF
}catch(Exception e){ %][$y7
e.printStackTrace(); [X">vaa
} finally{ 1u"*09yZd
try{ 2~&hstd%
if(ps!=null) { /q"d`!h)w
ps.clearParameters(); sE%<"h\_0
ps.close(); }L$Xb2^l
ps=null; 60aKT:KLC_
} `f6)Q`n
}catch(SQLException e){} $v'Y:
DBUtils.closeConnection(conn); Ueg N-n
} JXLWRe
} kBiBXRt
public long getLast(){ @ "{' j
return lastExecuteTime; 5h|m4)$
} U.hERe~X
public void run(){ P7wqZ?
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { MB8SB
//System.out.print("lastExecuteTime:"+lastExecuteTime); s@ 20#D
//System.out.print(" now:"+now+"\n"); j.;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); P"bknXL
lastExecuteTime=now; m/<F 5R
executeUpdate(); :(l $^
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} O\4+_y
else{ &vFqe,Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Kl aZZJ
} j
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} 4P4 Fo1
} Zc%foK{
//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 P!FEh'.
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类写好了,下面是在JSP中如下调用。 Q$3\ /mz
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<% y^d[( c
CountBean cb=new CountBean(); KM/U?`6>:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [*9YIjn
CountCache.add(cb); gv#c~cX]
out.print(CountCache.list.size()+"<br>"); . Z*j!{@c
CountControl c=new CountControl(); #
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c.run(); _)zmIB(}m
out.print(CountCache.list.size()+"<br>"); ws>WA{]gq
%>