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: zKWcDbj
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CountBean.java Rd5r~iT
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/* 7b,u|F
* CountData.java HzT"{N9
* !58-3F%P
* Created on 2007年1月1日, 下午4:44 w7"Z@$fs
* *~|xj,md
* To change this template, choose Tools | Options and locate the template under QP?Z+P<
* the Source Creation and Management node. Right-click the template and choose .Tdl'y:..
* Open. You can then make changes to the template in the Source Editor. y@G5I>v
*/ Px}#{fkS
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package com.tot.count; U&/Jh^Yy
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/** B" wk:\zC
* 2Fce| Tn
* @author It4J\S
*/ @M"h_Z1#
public class CountBean { pVw)"\S%
private String countType; c|Nv^V*2
int countId; d3(T=9;f2
/** Creates a new instance of CountData */ x1$tS#lS
public CountBean() {} mD)_quz.sk
public void setCountType(String countTypes){ ~'HwNzDQc
this.countType=countTypes; Ajhrsa\~a
} !+T+BFw.
public void setCountId(int countIds){ %?C{0(Z{
this.countId=countIds; gRKmfJ*u
} kO\(6f2|x
public String getCountType(){ 59p'Ega.
return countType; 5sx-u!7
} t_WNEZW7f
public int getCountId(){ l0b Y
return countId; R {+Rvk
} 1DGVAIcD
} ~/hP6*
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CountCache.java 1z$;>+g<
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/* h]c-x(+
* CountCache.java ?jBna
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*
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* Created on 2007年1月1日, 下午5:01 s0.yPA
* Hi9 ;i/
* To change this template, choose Tools | Options and locate the template under PS@`
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* the Source Creation and Management node. Right-click the template and choose |]]Xee]
* Open. You can then make changes to the template in the Source Editor. Zi2NgVF
*/ NQ{ XIN~
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package com.tot.count; w=3@IW
import java.util.*; \p.Byso,
/** DCmNxN
* cu|#AW
* @author *KFsO1j
*/ !/['wv@
public class CountCache { M\8FjJ>9
public static LinkedList list=new LinkedList(); 3`k1
/** Creates a new instance of CountCache */ q=}Lm;r
public CountCache() {} j46fQ
public static void add(CountBean cb){ ?ae:9ZcH
if(cb!=null){ ZQnJTS+ Rd
list.add(cb); M&y!w
} EH] 5ZZ[Z
} 6U7z8NV&[
} RWXj)H)w
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CountControl.java &H,j
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/* l8%x(N4
* CountThread.java QM9~O#rL
* Z%XBuq:BY
* Created on 2007年1月1日, 下午4:57 Nd#t !=
* us4.-L
* To change this template, choose Tools | Options and locate the template under Lz=nJn
* the Source Creation and Management node. Right-click the template and choose !Il>,q&F
* Open. You can then make changes to the template in the Source Editor. C_PXh>H]'
*/ [FC7+
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package com.tot.count; ]^&DEj{
import tot.db.DBUtils; {{[).o/
import java.sql.*; ^QB/{9 #
/** |RwD]2H
* CjOaw$s
* @author B8|=P&L7N
*/ &.+[~2
public class CountControl{ M`KrB5a+6
private static long lastExecuteTime=0;//上次更新时间 ()(@Qcc
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zY\v|l<T
/** Creates a new instance of CountThread */ Q]w;o&eo
public CountControl() {} fmA&1u/xMs
public synchronized void executeUpdate(){ HHCsWe-
Connection conn=null; Fx0K.Q2Y0
PreparedStatement ps=null; 8b(UqyV
try{ nPfVZGt
conn = DBUtils.getConnection(); <hdR:k@#
conn.setAutoCommit(false); //e.p6"8h
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )wpBxJ;dB}
for(int i=0;i<CountCache.list.size();i++){ /+sn-$/"i
CountBean cb=(CountBean)CountCache.list.getFirst(); rc*3k
CountCache.list.removeFirst(); 7-w
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ps.setInt(1, cb.getCountId()); W&z.O
ps.executeUpdate();⑴ >?b/_O
//ps.addBatch();⑵ :{LVS
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} &.=d,XKN
//int [] counts = ps.executeBatch();⑶ U-3KuR+0
conn.commit(); ZGzrh`j{-
}catch(Exception e){ .pi#Z/v
e.printStackTrace(); ;#3!ZB:}
} finally{ fbwo2qe@K
try{ 6}x^T)R
if(ps!=null) { M$%aX,nk'
ps.clearParameters(); vjZX8KAiZ
ps.close(); [G[HQ)A
ps=null; b\][ x6zJp
} _7]5Q
}catch(SQLException e){} E7^tU416
DBUtils.closeConnection(conn); ')bx1gc(?
} o&;+!Si@T
} 2*Z~JM
public long getLast(){ P)^K&7X
return lastExecuteTime; ;r-
\h1iA'
} 6O$OM
public void run(){ MrLDe{^C2
long now = System.currentTimeMillis(); ]! [ewO@
if ((now - lastExecuteTime) > executeSep) { X LA
//System.out.print("lastExecuteTime:"+lastExecuteTime); W5_t/_EWD
//System.out.print(" now:"+now+"\n"); 4'Vuhqk
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Nh]eZ3O
lastExecuteTime=now; a%;$l_wVT:
executeUpdate(); *J8j_-i,R
} g}$]K!F
else{ WsJ3zZc
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #R305
} q'3=
} *FK!^Y
} Z?XE~6aP>
//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 iIcO_ZyA
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类写好了,下面是在JSP中如下调用。
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<% uzho>p[ae
CountBean cb=new CountBean(); H `),PY2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +X
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CountCache.add(cb); _
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out.print(CountCache.list.size()+"<br>"); l]T|QhiVd
CountControl c=new CountControl(); ZaH<\`=%
c.run(); qK.8^{b
out.print(CountCache.list.size()+"<br>"); hP`3Ao
%>