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: u\50,N9Wp{
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CountBean.java tv5SQ+AI3
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/* ZZ#S\*
* CountData.java }.x?$C+\"
* a(F%M
* Created on 2007年1月1日, 下午4:44 A%pcPzG;
* XSXS;Fh)
* To change this template, choose Tools | Options and locate the template under ENygD
* the Source Creation and Management node. Right-click the template and choose 66v6do7
* Open. You can then make changes to the template in the Source Editor. :hZYh.y\l
*/ op;OPf,
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package com.tot.count; k\A8Z[
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/** q* +}wP
* Ve<l7U;
* @author fVw+8 [d0
*/ $`mxOcBmQ
public class CountBean { fs\l*nBig
private String countType; +[ !K
int countId; LyH{{+V
/** Creates a new instance of CountData */ \It8+^d@
public CountBean() {} F8f@^LVM/
public void setCountType(String countTypes){ @a+1Ri`)
this.countType=countTypes; +g%kr~w=
} Pr9$(6MX
public void setCountId(int countIds){ Iell`;
this.countId=countIds; K%O%#Kk
} A?=g!( wB
public String getCountType(){ Ng2qu!F7
return countType; e+j7dmGa
} .hXxh)F
public int getCountId(){ QYPsqkF*
return countId; Ap=LlZ
} uD_iyK0,
} UO>ADRs}
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CountCache.java d[J+):aW
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/* >T=($:n
* CountCache.java vdV@G`)HPr
* ZG3u
* Created on 2007年1月1日, 下午5:01 ihdN{Mx<2
* Y:XE4v/)@L
* To change this template, choose Tools | Options and locate the template under /0IvvD!7N
* the Source Creation and Management node. Right-click the template and choose nD6NLV%2x
* Open. You can then make changes to the template in the Source Editor. 1TJ2HO=Y
*/ :2vk
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package com.tot.count; r3*0`Rup
import java.util.*; A}W)La\
/** !RN(/ &%y
* v'mRch)d
* @author BagO0#
*/ a"@k11
public class CountCache { x\T 9V~8a
public static LinkedList list=new LinkedList(); jhl9
/** Creates a new instance of CountCache */ /_rEI,[k
public CountCache() {} ]c4?-Vq%u
public static void add(CountBean cb){ gMS-mkZ
if(cb!=null){ 3 -Nwg9U
list.add(cb); B&3oo
} Iy% fg',%
} L)p*D(
} MOi.bHCQJP
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CountControl.java n]S
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/* MEf`&<t
* CountThread.java M{w[hV
* `lygJI?H+{
* Created on 2007年1月1日, 下午4:57 FxeDjAP
* e)"]H*
* To change this template, choose Tools | Options and locate the template under ?NkweT(
* the Source Creation and Management node. Right-click the template and choose l];w,(u{
* Open. You can then make changes to the template in the Source Editor. q$x$ 4
*/ 9$U@h7|Q`
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package com.tot.count; >>22:JI`
import tot.db.DBUtils; D+.<
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import java.sql.*; /P { Zo
/** 2O;Lw@W
* 8`~M$5!
* @author uyZ
*/ P@lDhzd
public class CountControl{ O|wu;1pQ
private static long lastExecuteTime=0;//上次更新时间 )IQ5Qu
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 q% *-4GP
/** Creates a new instance of CountThread */ >ka*-8?
public CountControl() {} ~QzUQYG*
public synchronized void executeUpdate(){ qRi;[`
Connection conn=null; jd ]$U_U(
PreparedStatement ps=null; =A[:]),v
try{ ts|dk%
conn = DBUtils.getConnection(); A8tzIh8
conn.setAutoCommit(false); ;r<(n3"F
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b/;!yOF
for(int i=0;i<CountCache.list.size();i++){ +c'b=n9j
CountBean cb=(CountBean)CountCache.list.getFirst(); uzG{jc^
CountCache.list.removeFirst(); KT'Ebb]
ps.setInt(1, cb.getCountId()); gJ;jh7e@
ps.executeUpdate();⑴ PY.4J4nn|
//ps.addBatch();⑵ IY_u|7d
} ^K[WFi N}
//int [] counts = ps.executeBatch();⑶ k+qxx5{
conn.commit(); v_=xN^R
}catch(Exception e){ }#'I,?_k
e.printStackTrace(); f0"N
} finally{ LelCjC{`1
try{ ;6+e !h'1
if(ps!=null) { =T7lv%u
ps.clearParameters();
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ps.close(); 5@ c/,6l
ps=null; (h&XtFul}
} q-?
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}catch(SQLException e){} 8d4:8}
DBUtils.closeConnection(conn); 4sJM!9eb[
} -o:
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} ;zq3>A
public long getLast(){ itotn!Wb`
return lastExecuteTime; }enS'Fpf`
} R;yi58Be
public void run(){ B8=r^!jEL
long now = System.currentTimeMillis(); @9$u!ny0
if ((now - lastExecuteTime) > executeSep) { 7
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//System.out.print("lastExecuteTime:"+lastExecuteTime); \Dn47V{7-
//System.out.print(" now:"+now+"\n"); Q5K<ECoPk
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /xS4>@hn
lastExecuteTime=now; MZPXI{G
executeUpdate(); ?so=k&I-M
} sWtT"7>x
else{ q!fdiv`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); s}1S6*Cr
} mE>v (JY
} t 0 omJP
} y"bSn5B[
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 _U
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类写好了,下面是在JSP中如下调用。 S{uKm1a
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<% H]I^?+)9
CountBean cb=new CountBean(); <q}w, XU
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); PJ$C$G
CountCache.add(cb); Uj/m
out.print(CountCache.list.size()+"<br>"); #saK8; tp
CountControl c=new CountControl(); E\$7tXQK6
c.run(); ox|K2A
out.print(CountCache.list.size()+"<br>"); `S)*(s?T
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