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: i>CR{q
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CountBean.java P{`fav
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/* iWr
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* CountData.java /c-k{5mH%
* L?0IUGY
* Created on 2007年1月1日, 下午4:44 \eQPvkx2
* Ph.RWy")
* To change this template, choose Tools | Options and locate the template under #<m2Xo?d]
* the Source Creation and Management node. Right-click the template and choose %'e$N9zd
* Open. You can then make changes to the template in the Source Editor. 2|RoN)%
*/ x$ TLj
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package com.tot.count; g +gcH
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/** '@#(jY0_
* ~-lUS0duh
* @author |r;>2b/ x
*/ e<`?$tZ3
public class CountBean { >Jn` RsuV
private String countType; lnjs{`^
int countId; o(l%k},a
/** Creates a new instance of CountData */ )AdwA+-x
public CountBean() {} UCj+V@{
public void setCountType(String countTypes){ tCR~z1
this.countType=countTypes; m3P7*S5NJ7
} ,f,+) C$
public void setCountId(int countIds){ IV':sNV
this.countId=countIds; ~.U\Y
} +/mCYI
public String getCountType(){ +=|%9%
return countType; 3%o}3.P,:@
} &LB`
public int getCountId(){ '3Fb[md54
return countId; E
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} T5T[$%]6
} oPbziB8
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CountCache.java J
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/* D[6sy`5l
* CountCache.java if\`M'3Xx
* })uyq_nz
* Created on 2007年1月1日, 下午5:01 3?_%|;ga
* A8S9HXL
* To change this template, choose Tools | Options and locate the template under 0/7.RpX,.
* the Source Creation and Management node. Right-click the template and choose x*TJYST
* Open. You can then make changes to the template in the Source Editor. l>s@&%;Mg
*/ /FPO'} 6i
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package com.tot.count; upeioC q
import java.util.*; v6L]3O1
/** @/$i
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* *(]ZdB_2
* @author H)dZ0n4T
*/ +eLL)uk
public class CountCache { b~YIaD[Z
public static LinkedList list=new LinkedList(); 368 g>/#'
/** Creates a new instance of CountCache */ TMsCl6dB
public CountCache() {} " L,9.b
public static void add(CountBean cb){ pSYEC,0B
if(cb!=null){ #(+V&<K
list.add(cb); ? `kZ 6$
} =9p3^:S
} '`W6U]7>
} % hH> %
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CountControl.java Au(oKs<
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/* #67 7,dn
* CountThread.java ;7H^;+P
* +/ M%%:>mY
* Created on 2007年1月1日, 下午4:57 @*=5a(#
* jPx}-_jM
* To change this template, choose Tools | Options and locate the template under {L.uLr_?e
* the Source Creation and Management node. Right-click the template and choose _nX8f
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* Open. You can then make changes to the template in the Source Editor. :B7U),T
*/ S>j.i
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package com.tot.count; 6P,uy;PJ
import tot.db.DBUtils; N:+d=G`x
import java.sql.*; `YMd0*
/** SdnO#J}{
* GWWaH+F[h
* @author H(M{hfa|
*/ m"'`$ /_
public class CountControl{ 9 v8^uPA
private static long lastExecuteTime=0;//上次更新时间 ,LmP >Q.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~0?B
/** Creates a new instance of CountThread */ 6mIK[Qnp
public CountControl() {} PqF&[M<)
public synchronized void executeUpdate(){ /J&DYxl":
Connection conn=null; [9MbNJt 8~
PreparedStatement ps=null; 3Z#WAhfS:
try{ ?*7Mn`
conn = DBUtils.getConnection(); -g|ji.
conn.setAutoCommit(false); WA:r4V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); KU]o=\ak%
for(int i=0;i<CountCache.list.size();i++){ P46Q3EE
CountBean cb=(CountBean)CountCache.list.getFirst(); ?gjx7TQ?
CountCache.list.removeFirst(); v#X#F9C
ps.setInt(1, cb.getCountId()); .`v%9-5v
ps.executeUpdate();⑴ AR$SQ_4
//ps.addBatch();⑵ )%n$_N n
} MQ0rln?
//int [] counts = ps.executeBatch();⑶ difX7)\
conn.commit(); _ F|}=^Z`
}catch(Exception e){ g+<[1;[-
e.printStackTrace(); r}D#(G$
} finally{ U)aftH
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try{ .|s,':hA
if(ps!=null) { vP? T
ps.clearParameters(); ~gNFcJuy
ps.close(); {0-rnSjC
ps=null; rcY &n^:
} MPw?HpM
}catch(SQLException e){} _jgtZ
DBUtils.closeConnection(conn); $7i[7S4
} Nv6"c<(L=
} <dr2 bz
public long getLast(){ D&~%w!
return lastExecuteTime; Vry_X2
} HSAr6h
public void run(){ \/V#,O
long now = System.currentTimeMillis(); OIjSH~a.
if ((now - lastExecuteTime) > executeSep) { 6CW5ay_,
//System.out.print("lastExecuteTime:"+lastExecuteTime); x',6VTz^
//System.out.print(" now:"+now+"\n"); &`tAQN*Z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4udj"-V
lastExecuteTime=now; S'hUh'PZ
executeUpdate(); ~{vB2
} {s*2d P)
else{ !=a]Awr\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ',LC!^:~Nw
} Zzz94`
} <1<xSr
} 6DgdS5GhT_
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 oVPr`]
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类写好了,下面是在JSP中如下调用。 Ek6g?rj_
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<% o;
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CountBean cb=new CountBean(); N3@[95
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); g-"G Zi
CountCache.add(cb); c$tX3ug6I
out.print(CountCache.list.size()+"<br>"); :XG~AR/
CountControl c=new CountControl(); mw;4/
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c.run(); >TBXT+
out.print(CountCache.list.size()+"<br>"); zR]!g|;f
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