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: 6}Tftw$0z
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CountBean.java 1a V32oK
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/* ~av#r=x
* CountData.java 4 qY
* ks6iy}f7
* Created on 2007年1月1日, 下午4:44 + 9|0\Q
* \'[tfSB
* To change this template, choose Tools | Options and locate the template under G4~@
* the Source Creation and Management node. Right-click the template and choose i2(v7Gef
* Open. You can then make changes to the template in the Source Editor. \P9ms?((A
*/ 1n}#54
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package com.tot.count; QdcuV\B}
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/** lw}7kp4
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* (!N2,1|
* @author ,%N[FZ`|
*/ .{ljhE:
public class CountBean { pjTJZhT2 I
private String countType; $N}t)iA
int countId; YEaT_zWG0
/** Creates a new instance of CountData */ 3h>L0
public CountBean() {} _->+Hjj ^
public void setCountType(String countTypes){ ~Js kA5h|&
this.countType=countTypes; .I_<\h7
}
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public void setCountId(int countIds){ %xG<hNw/
this.countId=countIds; yvzH}$!]
} *s"OqTM]x
public String getCountType(){ IQtQf_"e1
return countType; 3 )#Nc|
} EK[J!~
public int getCountId(){ irq{ 21
return countId; "+7E9m6I
} U*\K<fw
} Z'2AsT
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CountCache.java 3(t,x
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/* v{ohrpb0v
* CountCache.java F<6(Hw#>
* x*'H@!!G
* Created on 2007年1月1日, 下午5:01 5psJv|Zo]
* `o }+2Cb
* To change this template, choose Tools | Options and locate the template under cAwqIihZ
* the Source Creation and Management node. Right-click the template and choose w}OBp^V^
* Open. You can then make changes to the template in the Source Editor. >lQa"F=
*/ 5fiWo^s}
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package com.tot.count; uF}dEDB|;
import java.util.*; ys`oHSf
/** BLaNS4e
* /t7f5mA
* @author Haktr2I
*/ C"**>OGe
public class CountCache { 82EvlmD
public static LinkedList list=new LinkedList(); ^W:a7cMw
/** Creates a new instance of CountCache */ 'SlZ-SdR
public CountCache() {} L8h!%56s
public static void add(CountBean cb){ k,=<G,
if(cb!=null){ FI?J8a
list.add(cb); yn]Sc<uK
} &@CUxK
} \a|~#N3?
} fvH{va.
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CountControl.java Ot\[Ya''
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/* e<9 ^h)G
* CountThread.java u1y>7,Z6W
* e<1Ewml(]
* Created on 2007年1月1日, 下午4:57 uyk;]EYjHZ
* ?uL-qsU
* To change this template, choose Tools | Options and locate the template under +3-5\t`
* the Source Creation and Management node. Right-click the template and choose y6d!?M(0U
* Open. You can then make changes to the template in the Source Editor. g3[-[G^5
*/ @SxZ>|r-|v
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package com.tot.count; I9+h-t
import tot.db.DBUtils; RDHK'PGA
import java.sql.*; yBs-bp"-
/** =Jw*T[ E
* 57;0,k5Gy
* @author !<~.>5UQ
*/ >M{98NH
public class CountControl{ NI,>$@{
private static long lastExecuteTime=0;//上次更新时间 `~=z0I
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 F::Ki4{jJ
/** Creates a new instance of CountThread */ juF=ZW%i
public CountControl() {} =,N"% }
public synchronized void executeUpdate(){
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Connection conn=null; LFi* O&
PreparedStatement ps=null; zT&"rcT">
try{ )=K8mt0qob
conn = DBUtils.getConnection(); Myg;2 .
conn.setAutoCommit(false); fm^`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); l"dXL"h
for(int i=0;i<CountCache.list.size();i++){ ] WYub1
CountBean cb=(CountBean)CountCache.list.getFirst(); UTu~"uCR
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); .EHq.cde
ps.executeUpdate();⑴ aL&egM*
//ps.addBatch();⑵ 9<3}zwJ
} __tA(uA
//int [] counts = ps.executeBatch();⑶ k -R"e
conn.commit(); _MIheCvV
}catch(Exception e){ hV,T889'
e.printStackTrace(); x!s=Nola
} finally{ s=jH1^
try{ pl@K"PRE
if(ps!=null) { w$iPFZC'
ps.clearParameters(); ! })Y9oZc8
ps.close(); ]5a3e+
ps=null; Gq[5H(0/c
} P(@Q[XQ2
}catch(SQLException e){} 9Ca0Tu
DBUtils.closeConnection(conn); d\3 %5Y
} 2Uf/'
} b#6mUl2
public long getLast(){ (c}!gjm
return lastExecuteTime; 1CZO+MB&"$
} N\tFK*U^I
public void run(){ I*>q7Hsu
long now = System.currentTimeMillis(); x5\D u63
if ((now - lastExecuteTime) > executeSep) { fATVAv
//System.out.print("lastExecuteTime:"+lastExecuteTime); F~rl24F
//System.out.print(" now:"+now+"\n"); aLW3Ub{h
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^vSSG5 :
lastExecuteTime=now; :!CnGKgt
executeUpdate(); vdUKIP
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} GL9'dL|
else{ Z VdQ$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); J{a9pr6
} b5%<},ySq
} T3=h7a %=
} ,m0M:!hK
//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 q6E'W" Q
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类写好了,下面是在JSP中如下调用。 ~AaEa,LQ
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<% l+y;>21sTu
CountBean cb=new CountBean(); ~-H3]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m0.g}N-w
CountCache.add(cb); +{;wOQ.
out.print(CountCache.list.size()+"<br>"); $A,YQH+
CountControl c=new CountControl(); kQ&Q_FSO
c.run(); 8#,_%<?UVy
out.print(CountCache.list.size()+"<br>"); @C=gMn.E
%>