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: >w"k:O17
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CountBean.java 2aUy1*aM
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/* r8E)GBH-|
* CountData.java SBBi"U:
* +8AGs,
* Created on 2007年1月1日, 下午4:44 KDX34Fr1
* qj5V<c;h%W
* To change this template, choose Tools | Options and locate the template under <X_I`
* the Source Creation and Management node. Right-click the template and choose le-Q&*
* Open. You can then make changes to the template in the Source Editor. g0D(:_QXp:
*/ ,1+)qv#|i
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package com.tot.count; X_eh+>D
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/** _JjR=
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* v}$KlT
* @author [l2ds:
*/ QM
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public class CountBean { M8BN'%S
private String countType;
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int countId; {\Eqo4A5}
/** Creates a new instance of CountData */ zMkjdjb
public CountBean() {} aAr gKM f
public void setCountType(String countTypes){ OXs-gC{b
this.countType=countTypes; 7aJLC!
} 0OndSa,
public void setCountId(int countIds){ H)),~<s
this.countId=countIds; pUs s_3
} w7?&eF(w(
public String getCountType(){ 32r2<QrX
return countType; #mNM5(o
} |[tlR`A $
public int getCountId(){ 8()L }@y
return countId; 5m`@ 4%)zp
} yu'2
} 8 ]N
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CountCache.java Efm37Kv5l
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/* 4Lo8Eue
* CountCache.java ]E1aIt
* Rl7V~dUY
* Created on 2007年1月1日, 下午5:01 /Ot=GhN]
* <|_/i/H
* To change this template, choose Tools | Options and locate the template under #-ioLt%
* the Source Creation and Management node. Right-click the template and choose :h 1-i
* Open. You can then make changes to the template in the Source Editor. jJc?/1 jv
*/ ~N+bD
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package com.tot.count; Q7X6OFl?
import java.util.*; ]wg+zOJu]+
/** -'FzH?q:
* IS`1}i$1%
* @author :"9 :J
*/ $6~D 2K
public class CountCache { }+KSZ,
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ }JXAG/<
public CountCache() {} _cqBp7
public static void add(CountBean cb){ 7(;M
if(cb!=null){ 2f8fA'|O
list.add(cb); Fi+v:L|
} PiMW29B^
} - Dm/7Sxd`
} pei-R
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CountControl.java e&G!5kz!
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/* ^YddVp
* CountThread.java \IL/?J
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* S}Wj+H;
* Created on 2007年1月1日, 下午4:57 *f8;#.Re
* c"w}<8
* To change this template, choose Tools | Options and locate the template under A)/
8FYc
* the Source Creation and Management node. Right-click the template and choose o}&TFhT
* Open. You can then make changes to the template in the Source Editor. UPs*{m
*/ .lVC>UT
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package com.tot.count; Hi$J@xU
import tot.db.DBUtils; (9r\YNK
import java.sql.*; vdFy}#X
/** iUl5yq
* }W{rDc kv
* @author }D_h*9
*/ pi)7R:i
public class CountControl{ 3.M<ATe^
private static long lastExecuteTime=0;//上次更新时间 J0BA@jH5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 x8I=I"Sp
/** Creates a new instance of CountThread */ "
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public CountControl() {} BsV2Q`(gT
public synchronized void executeUpdate(){ kwRXNE(k]_
Connection conn=null; 8)IpQG
PreparedStatement ps=null; \.+.VK
try{ iiS^xqSNCt
conn = DBUtils.getConnection(); }%_h|N
conn.setAutoCommit(false); C$o#zu q-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HvSKR1wL\
for(int i=0;i<CountCache.list.size();i++){ W]kh?+SZ
CountBean cb=(CountBean)CountCache.list.getFirst(); aIV(&7KT4
CountCache.list.removeFirst(); >S4klW=*I
ps.setInt(1, cb.getCountId()); %a%x`S3
ps.executeUpdate();⑴ o7"2"(
=>
//ps.addBatch();⑵ dI'cZt~n
} qkB)CY7
//int [] counts = ps.executeBatch();⑶ Rg3 Lo ?
conn.commit(); .v<c_~y
}catch(Exception e){ \ .HX7v
e.printStackTrace(); ~|+!xh
} finally{ <fq?{z
try{ c e`3&
if(ps!=null) { 'EFSr!+
ps.clearParameters(); |_V i8Ly
ps.close(); 16"eyt>
ps=null; "L^Klk?Vn
} 8F|8zX&
}catch(SQLException e){} 0{bGVLp
DBUtils.closeConnection(conn); k,o|"9H
} b|F_]i T
} ~Xi_bTAyAW
public long getLast(){ b#%s!
return lastExecuteTime; q{/>hvl
} Bbuy
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public void run(){ L'k)
long now = System.currentTimeMillis(); TCAtb('D
if ((now - lastExecuteTime) > executeSep) { ;O=tSEe
//System.out.print("lastExecuteTime:"+lastExecuteTime); a f[<[2pma
//System.out.print(" now:"+now+"\n"); :G$f)NMK
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); nbM[?=WS
lastExecuteTime=now; fY3^L"R
executeUpdate(); wYnsd7@I
} tRU+6D
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else{ 1U[8OM{$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [<m1xr4"k
} JSXudz5c
} P,y*H_@k
} o33wePx,
//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
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类写好了,下面是在JSP中如下调用。 J7:VRf|,?(
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<% Pg[XIfBva
CountBean cb=new CountBean(); n}?XFx!%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); PveY8[i
CountCache.add(cb); _[ml<HW]
out.print(CountCache.list.size()+"<br>"); 5Ug.J{d
CountControl c=new CountControl(); 2QwdDKMS_
c.run(); ?Fgk$WqC
out.print(CountCache.list.size()+"<br>"); 7b7~D +b
%>