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: w1B<0'#
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CountBean.java )LswSV
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/* Jm![W8L
* CountData.java gwQvao
* ma}}Sn)Q
* Created on 2007年1月1日, 下午4:44 |#TXE|#ux
* $cK^23H/Fj
* To change this template, choose Tools | Options and locate the template under 7;HUE!5,^l
* the Source Creation and Management node. Right-click the template and choose ;.Zh,cU
* Open. You can then make changes to the template in the Source Editor. $(>f8)Uku(
*/ I^fPk
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package com.tot.count; TC-f%1(
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/** X*Z5 P
* 1<uwU(
* @author tE!'dpG5)
*/ 0&`}EXe<f
public class CountBean { #t5juX9Ho9
private String countType; b*9e1/]
int countId;
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/** Creates a new instance of CountData */ ;]h.m)~|
public CountBean() {} !cCg/
public void setCountType(String countTypes){ ^`&HWp
this.countType=countTypes; |t\KsW
} `I>], J/
public void setCountId(int countIds){ U5rxt^
this.countId=countIds; ug6r]0]
} WzG07 2w
public String getCountType(){ *4#on>
return countType; P`sN&Y~m
} gStY8Z!k
public int getCountId(){ 1hNEkpL^a
return countId; >5i ?JUZ
} +-HE'4mo
} C
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CountCache.java hZ#\t
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/* fjkT5LNxk
* CountCache.java #J.u
* R+^z y"~
* Created on 2007年1月1日, 下午5:01 @+0V& jc
* yGV{^?yoP
* To change this template, choose Tools | Options and locate the template under X'2Gi
* the Source Creation and Management node. Right-click the template and choose JfKg_&hM
* Open. You can then make changes to the template in the Source Editor. 9`&77+|;e
*/ t/Z!O
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package com.tot.count; >H?uuzi
import java.util.*; w$% BlqN
/** }9Qf #&o
* 7sN0`7
* @author !@yQK<0
*/ nB}e1
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public class CountCache { /a%KS3>V*
public static LinkedList list=new LinkedList(); 9<qx!-s2rr
/** Creates a new instance of CountCache */ ZX]A )5G
public CountCache() {} vUfO4yfdg
public static void add(CountBean cb){ F=5kF/}x-z
if(cb!=null){ Ko-QR(
list.add(cb); A xR\ned
} &u4Ve8#
} z{V8@q/
} T;%+ ]:w<
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CountControl.java E$&;]a
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/* ;l#?SYY
* CountThread.java (T2<!&0 @
* dff#{
* Created on 2007年1月1日, 下午4:57 :9O|l)N)W=
* o7QK8#
* To change this template, choose Tools | Options and locate the template under tQ6| PV
* the Source Creation and Management node. Right-click the template and choose tQCj)Ms 'X
* Open. You can then make changes to the template in the Source Editor. !z.^(Tj
*/ xF^r`
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package com.tot.count; YL!oF^XO
import tot.db.DBUtils; *q[^Q'jnN
import java.sql.*; Y/!0Q6<[2Y
/** tdb4?^.s
* fIlIH
* @author u4xA'X'~R
*/ Z_!9iA:X
public class CountControl{ ^zkd{ov
private static long lastExecuteTime=0;//上次更新时间 `O jvt-5}E
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~vkud+r
/** Creates a new instance of CountThread */ 2"_ 18l.
public CountControl() {} ;p .j
public synchronized void executeUpdate(){ Cb<~i
Connection conn=null; tl2Lq0
PreparedStatement ps=null; 1(D1}fcul
try{ q2D`1nT
conn = DBUtils.getConnection(); ;?#i]Bh>S
conn.setAutoCommit(false); 6.vNe
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \J\vp0[nO}
for(int i=0;i<CountCache.list.size();i++){ 8*"rZh}'
CountBean cb=(CountBean)CountCache.list.getFirst(); r$Kh3EEF`E
CountCache.list.removeFirst(); ],!pp3U
ps.setInt(1, cb.getCountId()); gZ~y}@Ly
ps.executeUpdate();⑴ 2GUhV*TN
//ps.addBatch();⑵ vatx+)
} lTd+{TF.
//int [] counts = ps.executeBatch();⑶ t>=GVu^
conn.commit(); 8F.(]@NY
}catch(Exception e){ H?ieNXP7{
e.printStackTrace(); ^S3A10f,
} finally{ X{4xm,B/
try{ .Pqj6Ko9
if(ps!=null) { Iy-u`S
ps.clearParameters(); \y<+Fac1S
ps.close(); pq@$&G
ps=null; UYlJO{|a
} {=UKTk/t8
}catch(SQLException e){} @)+i{Niuv
DBUtils.closeConnection(conn); xU:PhhS
} :s? y,
} ((n5';|N
public long getLast(){ Y'\3ux0]4'
return lastExecuteTime; o(vZ*^\
} X/K| WOO6
public void run(){ -_:JQ
long now = System.currentTimeMillis(); (d1V1t2r6
if ((now - lastExecuteTime) > executeSep) { T9,lblUQ
//System.out.print("lastExecuteTime:"+lastExecuteTime); oM m/!Dc
//System.out.print(" now:"+now+"\n"); ]ZBgE\[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `,<>){c|
lastExecuteTime=now; !<JG&9ODP
executeUpdate(); ^$3w&$K*
} HP1X\h!Ke
else{ h%4~0
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^2(";.m
} :6qUSE
} `=WzG"
} IiQWs1
//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 axt6u)4%7:
k0Oc,P`'*
类写好了,下面是在JSP中如下调用。 Va&KIHw
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<% zhD`\&G.
CountBean cb=new CountBean(); GhaAvyN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); j>0SE
CountCache.add(cb); DRS;lJ2
out.print(CountCache.list.size()+"<br>"); KHiYV
CountControl c=new CountControl(); ~6pCOS}
c.run(); &ij^FAM
out.print(CountCache.list.size()+"<br>"); h=mI{w*
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