Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ;[}<xw3):
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 _Boe"
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 Pm*N!:u
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Kf!8PR$
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分页支持类: ]l.qp5eQ
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java代码: Mc#w:UH[
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package com.javaeye.common.util; NrrnG]#p1
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import java.util.List; lm
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publicclass PaginationSupport { /v^1/i
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publicfinalstaticint PAGESIZE = 30; 9Nkr=/I"P
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privateint pageSize = PAGESIZE; 2kS]:4)T
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privateList items; :UrS@W^B
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privateint totalCount; D:yj#&I
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privateint[] indexes = newint[0]; OE4hGxG
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privateint startIndex = 0; Cb5Rr+K=
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public PaginationSupport(List items, int )`sEdVxbr
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totalCount){ i{9_C/
setPageSize(PAGESIZE); _ 3l ci
setTotalCount(totalCount); ,%zU5 hh
setItems(items); nn0`A3
setStartIndex(0); :"pA0oB
} ,iQRf@#W_b
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public PaginationSupport(List items, int ?k*%r;e>
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totalCount, int startIndex){ 9
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setPageSize(PAGESIZE); $%3"@$
setTotalCount(totalCount); ? !dy
setItems(items); DnZkZ;E/
setStartIndex(startIndex); [1\k'5rp
} !M&Qca2
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public PaginationSupport(List items, int !&n'1gJ)kd
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totalCount, int pageSize, int startIndex){ wM"PJG
setPageSize(pageSize); 2qF
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setTotalCount(totalCount); R2 I
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setItems(items); _7#9nJ3|
setStartIndex(startIndex); 1JFCYJy
} nX|f?5 O
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publicList getItems(){ "GTlJqhk
return items; _8f?
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} 'fqX^v5n
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publicvoid setItems(List items){ hPP,D\#
this.items = items; []v t\I
;
} 4w\@D>@}H
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publicint getPageSize(){ 5a PPq~%
return pageSize; _=wu>h&7
} B`)gXqBt
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publicvoid setPageSize(int pageSize){ K>tubLYh
this.pageSize = pageSize; "\x<Zg;
} #'@pL0dj
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publicint getTotalCount(){ |\lsTY&2
return totalCount; #c?xJ&bh
} l.
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publicvoid setTotalCount(int totalCount){ j!It1B
if(totalCount > 0){ \x,q(npHi
this.totalCount = totalCount; w
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int count = totalCount / xejQ!MAB
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pageSize; TvbkvK
if(totalCount % pageSize > 0) V?.')?'V
count++; =41g9UQ
indexes = newint[count]; C [Ap&S
for(int i = 0; i < count; i++){ ]r^/:M
indexes = pageSize * #}8l9[Q|M
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i; /{[Y l[{"<
} %a_ rYrL
}else{ w=ib@_:f
this.totalCount = 0; 8,0WHivg
} YPV@/n[N
} *WHQ1geI8
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publicint[] getIndexes(){ G<2OL#Y-
return indexes; eVXlQO
} g?e$B}%
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publicvoid setIndexes(int[] indexes){ ;yvx -
this.indexes = indexes; !R;NV|.eI6
} O7M8!3Eqm
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publicint getStartIndex(){ y*BS
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return startIndex; ?YeUA =[MC
} &!xePKvO6k
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publicvoid setStartIndex(int startIndex){ W7F1o[
if(totalCount <= 0) ,v#F6xv8
this.startIndex = 0; X\-IAv
elseif(startIndex >= totalCount) [{i"Au]
this.startIndex = indexes 1&,d,<
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[indexes.length - 1]; vDeb?n
elseif(startIndex < 0) n0ZrgTVJ
this.startIndex = 0; qy9RYIfZ
else{ @d+NeS
this.startIndex = indexes Skbd'j
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[startIndex / pageSize]; vky@L! &,
} D<16m<b
} ,esryFRG
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publicint getNextIndex(){ g+X .8>=
int nextIndex = getStartIndex() + 2ncD,@ij
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pageSize; #cnh
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if(nextIndex >= totalCount) u . xUM
return getStartIndex(); k
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else [1LlzCAFBw
return nextIndex; pM|m*k
} /:+f5\"-b
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - Z7="on4
^n @dC?
pageSize; 5~pQ$-
if(previousIndex < 0) 1 +0-VRl
return0; eTeZ^G
else ef Moi 'v
return previousIndex; l\HLlwYO
} **D3.-0u&
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} UdiogXZ
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抽象业务类 "CX@a"
java代码: uZg[PS=@!X
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/** y^*o%2/
* Created on 2005-7-12 t1Zcr#b>
*/ @U 6jd4?)
package com.javaeye.common.business; +sW;p?K7eO
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import java.io.Serializable; N4xCZb
import java.util.List; SqF `xw
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import org.hibernate.Criteria; |#Gug('
import org.hibernate.HibernateException; H,{WrWA
import org.hibernate.Session; B%.vEk)*
import org.hibernate.criterion.DetachedCriteria; G[bWjw86O
import org.hibernate.criterion.Projections; }%T8?d]
import ]U,c`?[7#
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org.springframework.orm.hibernate3.HibernateCallback; -PG81F&K
import ^D%hKIT
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org.springframework.orm.hibernate3.support.HibernateDaoS _oILZ,
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upport; -5 Q
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import com.javaeye.common.util.PaginationSupport; xpU7ZY
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public abstract class AbstractManager extends 4ZX6=-u^
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HibernateDaoSupport { (v)/h>vS
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privateboolean cacheQueries = false; -r'/PbV0
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privateString queryCacheRegion; 'bb*$T0=
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publicvoid setCacheQueries(boolean nj(\+l5
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cacheQueries){ )&") J}@
this.cacheQueries = cacheQueries; jY +u OH
} .,9e~6}
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publicvoid setQueryCacheRegion(String %0gcNk"=
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queryCacheRegion){ O u-/dE%
this.queryCacheRegion = c{,VU.5/
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queryCacheRegion; nn?h;KzB
} y!kU0
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publicvoid save(finalObject entity){ kR
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getHibernateTemplate().save(entity); Wp
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} J6C/`)+w
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publicvoid persist(finalObject entity){ TSEv^u)3
getHibernateTemplate().save(entity); >* )fmfY
} fN!lXPgM
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publicvoid update(finalObject entity){ .*k$abb
getHibernateTemplate().update(entity); k0(_0o
} ;_oJGII?br
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publicvoid delete(finalObject entity){ 5{Oq* |
getHibernateTemplate().delete(entity); wR%F>[6.{
} *I6W6y;E=
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publicObject load(finalClass entity, ;]PP+h
u= =`]\_@
finalSerializable id){ }I3m8A
return getHibernateTemplate().load ; "K"S[
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(entity, id); "|^-Yk\U
} !XqU'xxC
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publicObject get(finalClass entity, y7ZYo7avg
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finalSerializable id){ i!i=6m.q7
return getHibernateTemplate().get \5pBK
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(entity, id); Q^{XM
} z4iTf8
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publicList findAll(finalClass entity){ !x$6wzKa
return getHibernateTemplate().find("from MfU0*nVF~
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" + entity.getName()); :?P>))vT%
} [q!/YL3%
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publicList findByNamedQuery(finalString kc7,F2=F
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namedQuery){ f6])M)
return getHibernateTemplate {bP
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().findByNamedQuery(namedQuery); p&$O}AX|
} /_[?i"GW
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publicList findByNamedQuery(finalString query, WXs?2S*
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finalObject parameter){ I
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return getHibernateTemplate HPc~wX
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().findByNamedQuery(query, parameter); )_a;xB`S(
} WI6h
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publicList findByNamedQuery(finalString query, { u %xc"0y
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finalObject[] parameters){ sP~;i qk
return getHibernateTemplate 3%(,f,
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().findByNamedQuery(query, parameters); X#<+D1P
} !!+LFe4su
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publicList find(finalString query){ &[7z:`+Y##
return getHibernateTemplate().find AaLbJYuKd
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(query); 9U4 D$M
} w'6sJ#ba(
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publicList find(finalString query, finalObject 5q;c=oRUj
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parameter){ ^jE8
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return getHibernateTemplate().find p|>m 2(|
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(query, parameter); .G-L/*&%
} <)a7Nrc\T
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public PaginationSupport findPageByCriteria e81+as
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(final DetachedCriteria detachedCriteria){ G Ml JM
return findPageByCriteria 8gxo{<,9
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Y~k,AJ{ ^
} &)izh) FA
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public PaginationSupport findPageByCriteria sQmJ3 (:HO
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(final DetachedCriteria detachedCriteria, finalint +Kp8X53
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startIndex){ sV;q(,oru
return findPageByCriteria GmH`ipi
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(detachedCriteria, PaginationSupport.PAGESIZE, 3vHkhhYQ
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startIndex); Ce/D[%
} "$.B@[iY@
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public PaginationSupport findPageByCriteria kjF4c6v
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(final DetachedCriteria detachedCriteria, finalint TDX~?>P
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pageSize, +y^'\KN
finalint startIndex){ #x6EZnG
return(PaginationSupport) #wZbG|%
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getHibernateTemplate().execute(new HibernateCallback(){ PXFu
publicObject doInHibernate Vy6~O|68=
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(Session session)throws HibernateException { q)3QmA~
Criteria criteria = T>|Y_3YO_a
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detachedCriteria.getExecutableCriteria(session); Md&K#)9,(
int totalCount = Dxe]LES\]
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((Integer) criteria.setProjection(Projections.rowCount \olY)b[
)4RSo&9p`
()).uniqueResult()).intValue(); p2
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criteria.setProjection >*EJ6FPO
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(null); [QIQpBL
List items = m^ /s}WEqp
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criteria.setFirstResult(startIndex).setMaxResults #~4;yY\$I
Myf2"\}
(pageSize).list(); a4mRu|x
PaginationSupport ps = q ,+29
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new PaginationSupport(items, totalCount, pageSize, IdCE<Oj\
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return(List) getHibernateTemplate w~3z);
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().execute(new HibernateCallback(){ @O|`r(le
publicObject doInHibernate :jJ0 +Q
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(Session session)throws HibernateException { Z`#XB2,
Criteria criteria = <B'PB"R3y
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detachedCriteria.getExecutableCriteria(session); =
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return criteria.list(); 2J (nJT"
} )6%a9&~H
}, true); \wR\i^
} bc;?O`I<
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public int getCountByCriteria(final kG5Uc83#G
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DetachedCriteria detachedCriteria){ CSH*^nk':O
Integer count = (Integer) DT_%Rz~<
@ +a}O
getHibernateTemplate().execute(new HibernateCallback(){ -;Te+E_
publicObject doInHibernate &x$ps
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(Session session)throws HibernateException { ^O}J',Fm%f
Criteria criteria = 4wWfaL5"
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detachedCriteria.getExecutableCriteria(session); 4>/i,_&K K
return xZ(d*/6E
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criteria.setProjection(Projections.rowCount iba8G]2
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()).uniqueResult(); rxj#
} `XM0Mm%
}, true); t^2$ent
return count.intValue(); :(4q\~
} wxN&k$`a
} S4rm K&
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用户在web层构造查询条件detachedCriteria,和可选的 +:W? :\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 e7tio!
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PaginationSupport的实例ps。 DR]4Tc z#
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ps.getItems()得到已分页好的结果集 pD }b $
ps.getIndexes()得到分页索引的数组 TmK8z
ps.getTotalCount()得到总结果数 ?A04qk
ps.getStartIndex()当前分页索引 qE8Di\?
ps.getNextIndex()下一页索引 $ab{GxmX'4
ps.getPreviousIndex()上一页索引 SjIDzNI5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 'v=BAY=Ef
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 vu&ny&=`
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一下代码重构了。 c`N_MP
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我把原本我的做法也提供出来供大家讨论吧: +{}p(9w@
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首先,为了实现分页查询,我封装了一个Page类: 4q(,uk&R[
java代码: @Y<fj^]k
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/*Created on 2005-4-14*/ {Z1-B60P
package org.flyware.util.page; %d<UMbS^
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/** ,Ek6X)|@
* @author Joa WI.+9$1:P
* %IDl+_j
*/ [E"3?p
publicclass Page { /||8j.Tm
= )4bf"~8
/** imply if the page has previous page */ {hm-0Q
privateboolean hasPrePage; ;Wsl 'e/
JvaHH!>d/
/** imply if the page has next page */ ]mjKF\
privateboolean hasNextPage; .'4@Yp{=
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q
/** the number of every page */ [?(qhp!
privateint everyPage; 2wgcVQ
Awa
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/** the total page number */ \&U"7gSL
privateint totalPage;
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vV*/"'>
/** the number of current page */ JeAyT48!M
privateint currentPage; wRq
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/** the begin index of the records by the current !!mGsgnW
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query */ yVJ)JhV
privateint beginIndex; ey\(*Tu9
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/** The default constructor */ Ye^xV,U@
public Page(){ @V@<j)3P
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} 3E>]6
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/** construct the page by everyPage H>"P]Y)oX
* @param everyPage wy:euKB~
* */ ?ZkVk =t?
public Page(int everyPage){ `8TL*.9
this.everyPage = everyPage; E~8J<gE
} z5sKV7&\[n
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/** The whole constructor */ %6Y}0>gY
public Page(boolean hasPrePage, boolean hasNextPage, Ie8SPNY-H
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int everyPage, int totalPage, L:jv%;DM
int currentPage, int beginIndex){ F$9+WS`c
this.hasPrePage = hasPrePage; 2%MS$Fto
this.hasNextPage = hasNextPage; +!G)N~o
this.everyPage = everyPage; MW=rX>tE
this.totalPage = totalPage; tMo=q7ig
this.currentPage = currentPage; APU~y5vG (
this.beginIndex = beginIndex; pvRa
} s&DAO r!i
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/** =S\pI
* @return lg
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* Returns the beginIndex. u:,B&}j
*/ :%U
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publicint getBeginIndex(){ w2K>k/v{-
return beginIndex; ytV4qU82G
} t3!~=U
~$7YEs)
/** 0f;|0siTAm
* @param beginIndex HLh]*tQG
* The beginIndex to set. lvUWs
*/ ESe$6)P
publicvoid setBeginIndex(int beginIndex){ KnK\X>:
this.beginIndex = beginIndex; v,US4C|^3i
} j"&Oa&SH
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/** lnV!Xuf
* @return cQ0+kX<
* Returns the currentPage. Tcq@Q$H
*/ SWNT}{x]
publicint getCurrentPage(){ lW]&a"1$
return currentPage; ZZ>(o
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} u#3Cst8Y
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/** )xTu|V
* @param currentPage R5<:3tk=X
* The currentPage to set. |lVi* 4za%
*/ vnX~OVz2
publicvoid setCurrentPage(int currentPage){ 8=mx5Gwz-
this.currentPage = currentPage; Nm3CeU
} \r&(l1R
CR-2>,*a9
/** F5\{`
* @return ^YEMR C
* Returns the everyPage. GEki34
n0
*/ /)r[}C0
publicint getEveryPage(){ Pa ^_s
return everyPage; Gk|T1%
} #jw%0H;l]
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/** i\{fM}~W$
* @param everyPage SqoO"(1x
* The everyPage to set. eW[](lGWM
*/ 0'R}'
publicvoid setEveryPage(int everyPage){ AQ,%5MeqJ
this.everyPage = everyPage; w X.]O!^X~
} `V?NS,@$
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/** =8DS~J{
* @return Oq95zo
* Returns the hasNextPage. r<"k
/
*/ pAcu{5#7
publicboolean getHasNextPage(){ F4g3l
return hasNextPage; UR[UZ4G
} =AeOkie
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/** fc%C!^7
* @param hasNextPage dewN\
* The hasNextPage to set. -nB.
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*/ Ia>~ph#]{`
publicvoid setHasNextPage(boolean hasNextPage){ :) T#.(mR
this.hasNextPage = hasNextPage; EOf*1/Ih
} ^i17MvT'
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/** =n MAw&`
* @return l D]?9K29
* Returns the hasPrePage. {)-3g~
*/ q}J Eesf
publicboolean getHasPrePage(){ Vc
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return hasPrePage; - 4S4I
} zHvW@A'F
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/** 4HyD=6V#
* @param hasPrePage ,f[Oy:fr
* The hasPrePage to set. ,v(ikPzd
*/ e{*z4q1
publicvoid setHasPrePage(boolean hasPrePage){ Bv}nG|
this.hasPrePage = hasPrePage; <&}N[
} kT&GsR/
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/** /Fp@j/50
* @return Returns the totalPage. +<c(;Ucl?
* 7T=:dv
*/ {uiL91j.
publicint getTotalPage(){ v79\(BX
return totalPage; V"|j Dnn5
} wUmcA~3D
x c$jG?83#
/** wmit>69S
* @param totalPage m?`$NJST
* The totalPage to set. r7*'s
*/ _Ns_$_
publicvoid setTotalPage(int totalPage){ P".rm0@R
this.totalPage = totalPage; IPlkv{^
} Rhh.fV3
=OooTZb:x-
} 'k9 1;T[
o>\epQt~/p
rd}|^&e!Dy
,}$[;$ye
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 2sT\+C&H
3F9AnS
个PageUtil,负责对Page对象进行构造: !ziO1U
java代码: 9 H~OC8R:
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/*Created on 2005-4-14*/ -@`!p
package org.flyware.util.page; f_tC:T4a
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import org.apache.commons.logging.Log; A)u,Hvn
import org.apache.commons.logging.LogFactory; Tw9?U,]
-&r A<j
/** XE :JL_
* @author Joa {8J+Y}
* ,+E"s3NW
*/ -2*Pm1\Z
publicclass PageUtil { qbQH1<yS<
~*ll,<L:
privatestaticfinal Log logger = LogFactory.getLog ]llvG\
0%]F&|
(PageUtil.class); Z`kI6
}e&Z"H |
/** .T^e8
* Use the origin page to create a new page T3^(I~03
* @param page q! }O+(kt
* @param totalRecords Y
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* @return l\~F0Z/O
*/ EB[B0e7}
publicstatic Page createPage(Page page, int lag%}^
47
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totalRecords){ 5U%a$.yr
return createPage(page.getEveryPage(), 9Zpd=m8dU
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page.getCurrentPage(), totalRecords); #
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} (T2\
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/** C(5B/W6
* the basic page utils not including exception 4$jb-Aw
"9yQDS:
handler L2^M#G@t
* @param everyPage i 9w k)
* @param currentPage mEDi'!YE"
* @param totalRecords l*<RKY8
* @return page I?%iJ%
*/ Y@[Dy
publicstatic Page createPage(int everyPage, int hZLwg7X!
;Fm7!@u^0
currentPage, int totalRecords){ WY" `wM
everyPage = getEveryPage(everyPage); H6]z9 8
currentPage = getCurrentPage(currentPage); +umVl
int beginIndex = getBeginIndex(everyPage, \>r<z46x
%v 1NDhaXz
currentPage); ^jZ4tH3K
int totalPage = getTotalPage(everyPage, hha^:,
w&^_2<a2
totalRecords); 0|@*`-:VO
boolean hasNextPage = hasNextPage(currentPage, TClgywL
o<8=@ ^T
totalPage); TSAVXng
boolean hasPrePage = hasPrePage(currentPage); UqaV9
8!u8ZvbFG
returnnew Page(hasPrePage, hasNextPage, mA>u6Rlc
everyPage, totalPage, T_b$8GYfCY
currentPage, Dg2=;)"L
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beginIndex); uPveAK}h
} q3-V_~5^/z
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privatestaticint getEveryPage(int everyPage){ UFY_.N~
return everyPage == 0 ? 10 : everyPage; 7Q3a0`Iq
} Fb9!x/$tGV
7! "OF
privatestaticint getCurrentPage(int currentPage){ q\a'pp9d
return currentPage == 0 ? 1 : currentPage; _qQB.Dzo:
} /4PV<[
:_
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privatestaticint getBeginIndex(int everyPage, int E8s&.:;+
U<H<
!NV
currentPage){ yCT:U&8%F
return(currentPage - 1) * everyPage; 6`Af2Y_
} [<p7'n3x
DKxzk~sOM
privatestaticint getTotalPage(int everyPage, int XKt">W
Km9Y_`?
totalRecords){ yYM_
int totalPage = 0; 2dUVHu= +
YFY$iN~B,
if(totalRecords % everyPage == 0) ({_Dg43O'[
totalPage = totalRecords / everyPage; ?E:L6,a
else 98AX=%8
totalPage = totalRecords / everyPage + 1 ; N]6M4j!
szx7CP`<8
return totalPage; W4~:3Sk
} L+o"<LV]
`$odxo+
privatestaticboolean hasPrePage(int currentPage){ G 0;5I_D/
return currentPage == 1 ? false : true; dy%#E2f
} ypK1
sw
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privatestaticboolean hasNextPage(int currentPage, lYq4f|5H}m
s9'lw'
int totalPage){ Mk~]0d
return currentPage == totalPage || totalPage == <Fa]k'<^)
io{uN/!X_J
0 ? false : true; Vx6/Rehj
} B5Y
3GWhrx
8V$ :th('
D-<9kBZs
} ( d2|r)O
RiX~YLeM
u79,+H@ep
ZfYva(zP{Q
^ A`@g4!
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 *6trK`tx^
/X_g[*]?
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 `pzXh0}|
rL/e
做法如下: DZI:zsf;5Q
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 |3A/Og
a*Oc:$
的信息,和一个结果集List: r)G^V&96
java代码: tgP x!5U
W%xg;uzp
MWxv\o
/*Created on 2005-6-13*/ N5%zbfKM
package com.adt.bo; 9j;L-
"X }@VT=
import java.util.List; SXW8p>1Jw
(!@
Q\P
import org.flyware.util.page.Page; mu?6Phj
boJ
/** 5 uU.K3G7
* @author Joa 1dy>a=W
*/ z!r-g(^G
publicclass Result { 7z=zJ4C
3.
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private Page page; gfPht 5
-!k$ Z
private List content; "#a_--"k9
m6
)s X&
/** nf7l}^/UE
* The default constructor eXqS9`zKr
*/ d }"Dp
public Result(){ QKAo}1Pq
super(); Xo{|m[,
} Gs% cod
q@}eYQ=P|e
/** !e}LB%zf
* The constructor using fields JToc("V
* &GC`4!H
* @param page dvAvG.;U
* @param content .UUY9@
*/ $~[k?D
public Result(Page page, List content){ Ie[8Iot?bn
this.page = page; tCJ+OU5/
this.content = content; 4\.1phe$a
} 4nfpPNt
5gPcsn"D
/** fJb<<6C
* @return Returns the content. Nl3@i`;
*/ ~ "^]\3#
publicList getContent(){ 5f:Mb|.?
return content; YMidSfi
} %YI Xk1
=2
3H/
/** 43"`gF]
* @return Returns the page. V?a+u7*U&
*/ X_}2xo|T
public Page getPage(){ UKBVCAK
return page; }w0>mA0=H
} xMAfa>]{n
i,{'}B
/** _\9|acFT2O
* @param content q\P"AlpC!
* The content to set. LG0z|x(
*/ fI5]ed eS
public void setContent(List content){ ]ZQ3|ZJ?<
this.content = content; "QWF&-kAI
} =,/08Cs
D{]t50a.
/** ~JJuM
* @param page GvL)SVv?
* The page to set. E,F'k2yU
*/ 1 h.=c
publicvoid setPage(Page page){ \a|FhhI
this.page = page; P,2FH2Eyj
} Hqel1J
} ;^q@w
j{i3lGaN
7gL N7_2
:
"|M
V'XmMn)!
2. 编写业务逻辑接口,并实现它(UserManager, T+O Qa+E@P
\,-t]$9
UserManagerImpl) e;y\v/A
java代码: k* ayzg3F>
lzQmD/i*
. C g2Y
/*Created on 2005-7-15*/ E^:8Jehq
package com.adt.service; 7r`A6 \
!
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import net.sf.hibernate.HibernateException; gy
Jx>i
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import org.flyware.util.page.Page; !$/1Q+
? 1OZEzA!
import com.adt.bo.Result; /B$9B
`aj;FrF
/** 7X
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* @author Joa J33enQd
*/ 3;wAm/Z:Q
publicinterface UserManager { mVg$z
Hh_Yd)
public Result listUser(Page page)throws d-=RS]j;j
8n.sg({g
HibernateException; }9&Z#1/
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} 8i H'cX
_vQtV]
%S G**7
z|w@eQ",
uM!$`JN
java代码: F~;G[6}
-6URM`y'j
cmpT_51~O
/*Created on 2005-7-15*/ qq%\
package com.adt.service.impl; \`H"4r[?(
)20jZm*
import java.util.List; v"y0D
0b)^#+
import net.sf.hibernate.HibernateException; DrfOz#a0Uu
w4m-DR5
import org.flyware.util.page.Page; 'W!N1W@
import org.flyware.util.page.PageUtil; 8oM]gW;J~
?-40bb
import com.adt.bo.Result; b51{sL
import com.adt.dao.UserDAO; V Ae@P
import com.adt.exception.ObjectNotFoundException; q
.[hwm
import com.adt.service.UserManager; %^e~;i=2
s*"Yi~
/** O~E6"vQ
* @author Joa [D8u.8q
*/ y\=(;]S'
publicclass UserManagerImpl implements UserManager { V'kCd4
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private UserDAO userDAO; _0~WT
]}KoW?M
/** <r6e23
* @param userDAO The userDAO to set. av-l_iE
*/ {s=n "*Qp)
publicvoid setUserDAO(UserDAO userDAO){ s:_M+_7_
this.userDAO = userDAO; 2~:jg1
} E5-f{Qc
4NY00d/R
/* (non-Javadoc) 8db J'
* @see com.adt.service.UserManager#listUser @8IYJ{=
tY?_#rc
(org.flyware.util.page.Page) (7C&I-l
*/ gmU_# J%~
public Result listUser(Page page)throws h/I'9&J>*
wz!a;]agg
HibernateException, ObjectNotFoundException { ^tWt"GgC
int totalRecords = userDAO.getUserCount(); -8sm^A>C
if(totalRecords == 0) K+3dwQo
throw new ObjectNotFoundException >C6wm^bl
>(v%"04|e
("userNotExist"); `t0?PpUo
page = PageUtil.createPage(page, totalRecords); !$ $|zB%
List users = userDAO.getUserByPage(page); H+^93
returnnew Result(page, users); 4'&j<Ah[#
} ]zGgx07d
X bF;
} OYcf+p"<\
JfJUOaL
+-b:XeHSZ
~Wh}W((L
qo1eHn4
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 (~YFm"S
_{.=zv|3
询,接下来编写UserDAO的代码: 5hNjJqu
3. UserDAO 和 UserDAOImpl: 1J}i :i&
java代码: x?hdC)#DWI
bU`Ih# q
Vb${Oy+
/*Created on 2005-7-15*/ +&LzLF.bK
package com.adt.dao; Va^AEuzF
]<9=%m
import java.util.List; VieX5
O>zPWVwa
import org.flyware.util.page.Page; I y?_2m
y[U/5! `zV
import net.sf.hibernate.HibernateException; 7qfo%n"
X!+#1NPM
/** vmI2o'zi
* @author Joa h@{U>U7
*/ MA\^<x_?L}
publicinterface UserDAO extends BaseDAO { 71AR)6<R
;D Mv?-H
publicList getUserByName(String name)throws yN*HIN
E,6(/`0H*
HibernateException; D`nW9i7
Yg 8AMi
publicint getUserCount()throws HibernateException; 2ckAJcpEb/
d/Q}I[J.u
publicList getUserByPage(Page page)throws J(BtGGU'
19 h7 M
HibernateException; A>;Q<8rh
VE4Z;Dr"
} ,|gX?[o
K".\QF,:
GF6c6TXF@
2?3D`
`
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java代码: .&:GOD
GA19=gow
bM]\mo>z<
/*Created on 2005-7-15*/ hFORs.L&G
package com.adt.dao.impl; #UR4I2t*
wRgh`Hc\}
import java.util.List; |meo
&3x
\wH/_
import org.flyware.util.page.Page; cY+vnQm
wGd4:W
import net.sf.hibernate.HibernateException; OrXx0Hn
import net.sf.hibernate.Query; 7%p[n;-o&
i
! wzID
import com.adt.dao.UserDAO; y'(bp=Nq
tw.2h'D
/** > QwZt
* @author Joa p fj%AP:
*/ __U;fH{c
public class UserDAOImpl extends BaseDAOHibernateImpl F$kLft[:
TGnyN'P|
implements UserDAO { #q{i<E 07
Dp:u!tdbeg
/* (non-Javadoc) =}S*]Me5
* @see com.adt.dao.UserDAO#getUserByName O.7Q*^_
8'=8!V
(java.lang.String) @Q:5{?
*/ NTRw:'
publicList getUserByName(String name)throws N2yxli
0-
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HibernateException { PV?XpT
String querySentence = "FROM user in class {I s?>m4
v:s.V>{"S
com.adt.po.User WHERE user.name=:name"; !"u) `I2
Query query = getSession().createQuery Nrl&"IK|J
S>~QuCMY
(querySentence); /yHM=&Vg]
query.setParameter("name", name); lQs|B '
return query.list(); bP;cDQ(g
} 8i!~w 7z
uq;,h46ki
/* (non-Javadoc) H \$04vkR
* @see com.adt.dao.UserDAO#getUserCount() 76[O3%
*/
9XGzQ45R
publicint getUserCount()throws HibernateException { F{*S}&q*)o
int count = 0; 'L#qR)t
String querySentence = "SELECT count(*) FROM du2q6"
iqecm]Z0
user in class com.adt.po.User"; (5@9j
Query query = getSession().createQuery 8+Lig
w7Nb+/,sg
(querySentence); .Z=D|&!
count = ((Integer)query.iterate().next WeGT}
L]{ 1"`#
()).intValue(); A8JEig 3Ix
return count; 7p""5hw
} s&S8P;K|
`Q!|/B
/* (non-Javadoc) ;^)(q<]
* @see com.adt.dao.UserDAO#getUserByPage 5m")GWQaP@
.+XGbs]kCi
(org.flyware.util.page.Page) }+U} [G
*/ 1-@.[VI
publicList getUserByPage(Page page)throws \LB =_W$
nVI\Or[
HibernateException { XZhX%OT!
String querySentence = "FROM user in class <\k=j{@
[ V`j@dV
com.adt.po.User"; qX{m7
Query query = getSession().createQuery ehEXC
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(querySentence); >j1\]uo
query.setFirstResult(page.getBeginIndex()) i][7S mN
.setMaxResults(page.getEveryPage()); [07N<<
return query.list(); xw-x<7
} z^
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j3QpY9A
} /#J)EH4p
|RQ19m@
h'wOslyFa
YIA}F1:
wC@5[e$
至此,一个完整的分页程序完成。前台的只需要调用 2Mx9Kd'a
r
+r)'?zU
userManager.listUser(page)即可得到一个Page对象和结果集对象 11}fPWK
.?b2Bd!MC
的综合体,而传入的参数page对象则可以由前台传入,如果用 .fxI)
~o`I[-g)
webwork,甚至可以直接在配置文件中指定。 -ecP@,
6L~@jg~0A[
下面给出一个webwork调用示例: _+K[1P
java代码: *a Y`[,4#$
*&)<'6
c8mcJAc
/*Created on 2005-6-17*/ 'UO,DFq[Fl
package com.adt.action.user; ywlN4=
7G}vQO
import java.util.List; 0N.tPF}
Mn+;3qo{6
import org.apache.commons.logging.Log; BDY@&vF
import org.apache.commons.logging.LogFactory; +F ~;Q$T
import org.flyware.util.page.Page; .:,RoK1
#=R) s0j"
import com.adt.bo.Result; p~M1}mE
import com.adt.service.UserService; ann!"s_
import com.opensymphony.xwork.Action; y'4H8M2?
Iw~3y{\
/** Y?hC/6$7
* @author Joa 8Dpf{9Y-E
*/ ABEC{3fWpu
publicclass ListUser implementsAction{ zcItZP
W5?F?Dp!v
privatestaticfinal Log logger = LogFactory.getLog ZjY_AbD
w[PWJ! <
(ListUser.class); HbF.doXK
jz c/Olb
private UserService userService; H n+1I
ByeyUw
private Page page; YMP:T?vMVh
)NZ6!3[@
privateList users; %>'2E!%
/h%<e
/* !o &+
* (non-Javadoc) 6\4ny 0
* 9}kN9u
* @see com.opensymphony.xwork.Action#execute() !mK[kXo
*/ {s|rk
publicString execute()throwsException{ ]aq!@rDX
Result result = userService.listUser(page); wJh|$Vn
page = result.getPage(); IXt2R~b
users = result.getContent(); 9"2.2li5$
return SUCCESS; u3kK!2cdP
} UC^&&
2maI
o7VNw8Bp
/** YKLh$
* @return Returns the page. "+s#!Fh *
*/ *w4jE T>
public Page getPage(){ ,.tT9?
m
return page; ~c[}%Ir>
} _Jj/"?
2}]6~i
/** !*u5HVn
* @return Returns the users. b].:2
*/ H[V^wyi'z
publicList getUsers(){ v vlfL*f
return users; {6)fZpd)@
} ?ECmPS1
3tI=?E#
/** 8rXq-V_u
* @param page &/R@cS6}'
* The page to set. C.s{&
*/ @/yRE^c
publicvoid setPage(Page page){ Y5=~>*e
this.page = page; !U}A1)
} @B
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+GI[
Kq
/** 'Z'X`_
* @param users oT&JQ,i[2Q
* The users to set. Y32F{ z
*/ ]>/YU*\
publicvoid setUsers(List users){ !`\W8JT+
this.users = users; Dqe)8 r
} y?<[g;MuT
VgZ<T,SuW
/** Gk,{{:M:5
* @param userService MLY19 ;e
* The userService to set. M$-4.+G
*/ hxx,E>k
publicvoid setUserService(UserService userService){ _`/0/69
this.userService = userService; wQ!~c2a<8
} #`:s:bwM:
} 2ko7t9y&
tu77Sb
\8Mkb]QA
E xKH%I
nFW^^v<
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, vX)6N#D!
t*<vc]D
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 EG&^;uU
n=r}jRH1
么只需要: :7Rs$
-*Uk
java代码: (U2G"
)(*A1C[
FR0zK=\
<?xml version="1.0"?> aRq7x~j
)\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 8_>\A=
E
y4VCehdJ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- I"Ji_4QV
/`hr)
1.0.dtd"> p]`pUw{
J=*y>Zt-b
<xwork> g}Hk4+
tzi+A;>c(v
<package name="user" extends="webwork- WRh&4[G'
&[*_ -
interceptors"> X~0l1 @!
kR^7Z7+#*
<!-- The default interceptor stack name cAyR)Y!I
uByF*}d1
--> vIU+ZdBw
<default-interceptor-ref r {)d?Ho=
!/< 5.9!9r
name="myDefaultWebStack"/> 5|m|R"I*Y
KwPJ0
]('_
<action name="listUser" =t@m:
~0ZEnejy
class="com.adt.action.user.ListUser"> D\(,:_ge
<param 78+H|bH8
*IGxa
name="page.everyPage">10</param> =d~]*[8
<result ifTVTd7O
|rdG+>
name="success">/user/user_list.jsp</result> &-<"HW
</action> wuzz Wq
ol!o8M%Q
</package> KblOP{I
kjaz{&P
</xwork> n#z^uq|v
|GK [I
^eM=h
1GOa'bxm
lx$Y-Tb^F
\^Y#"zXo1
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Ep 5lmzg
vlyq2>TfR
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 (n" )
C$*`c6R
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 [7<X&Q
zmr=iK
^+`vh0TPQ
t)cG_+rJ
G]P4[#5
我写的一个用于分页的类,用了泛型了,hoho :U)e
8
bcM#KA
java代码: *Z{$0K
1"/V?ArfL
+ A0@#:B
package com.intokr.util; KG>.7xVWV7
!Q.c8GRUQ
import java.util.List; V.y+u7<3}
W3<O+ S&
/** KNY<"b
* 用于分页的类<br> n!eg"pL
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ,9?'Q;20
* V2g$"W?3
* @version 0.01 ljiq +tT
* @author cheng OzO_E8Kb\
*/ ]XPGlM
public class Paginator<E> { d[~c-G6
privateint count = 0; // 总记录数 |o!<@/iH=
privateint p = 1; // 页编号 X[@>1tl
privateint num = 20; // 每页的记录数 *uEU9fX
privateList<E> results = null; // 结果 S
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\W=
/** _
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* 结果总数 So`xd
*C!
*/ @b>]q$)(}
publicint getCount(){ 5&}icS
return count; FblGFm"P
} :[ITjkhde0
rA1
gH6D
publicvoid setCount(int count){ 8OBvC\%
this.count = count; 2$\f !6p
} s|,]Nb=z/
ZM|>Va/X
/** b%oma{I=.c
* 本结果所在的页码,从1开始 RLKO0 #
* J&3;6I
&
* @return Returns the pageNo. 3M@>kIT8
*/ +uT=Wb \
publicint getP(){ W/\7m\B
return p; 66|lQE&n
} M
j5C0P(
ZzKn,+
/** BbU&e z8P
* if(p<=0) p=1 "Y%\qw/wq
* ?0?'
* @param p 2f:'~ P56
*/ ItRGq
publicvoid setP(int p){ 'R'>`?Nh
if(p <= 0) w}YHCh
p = 1; )j9FB
this.p = p; 9723f1&Vd
} {>+$u"*
5vpf;
/** ITsJjcYw
* 每页记录数量 1B1d>V$*
*/ RF;N]A?*
publicint getNum(){ yjSN;3t71
return num; `2@-'/$\I|
} ?DRC!
9o^
Ee|@l3)
/** >N,G@{FR
* if(num<1) num=1 hV,3xrm?P
*/ *jJ62-o
publicvoid setNum(int num){ VLO>{"{'
if(num < 1) :?p{ga9
num = 1; p0tv@8C>
this.num = num; v4v+;[a%
} \;?\@vo<
mi-\PD>X
/** JNu - z:J
* 获得总页数 S1B/ClKWq
*/ m_Rgv.gE^
publicint getPageNum(){ R80R{Ze
return(count - 1) / num + 1; TtvS|09p;
} E$1^}RGT)
9:Y:Vx
/** jqLyX
* 获得本页的开始编号,为 (p-1)*num+1 cr/|dc'
*/ H 0h
publicint getStart(){ pP
r<8tm[
return(p - 1) * num + 1; {10ms_s
} tS9m8(Hr%Q
[qXpi'q[
/** 7d<v\=J}
* @return Returns the results. z=fag'fzM
*/ -?]ltn9!
publicList<E> getResults(){ lvN{R{7>
return results; W+eN%w5
} ;+jp,( 7
{jVFlKP>
public void setResults(List<E> results){ \8$`:3,@
this.results = results; OM.^>=
} M ?3N
w %zw+E
public String toString(){ 6,7omYof
StringBuilder buff = new StringBuilder U=t'>;(g
VsmL#@E
(); .( J/*H
buff.append("{"); 3K{8sFDO
buff.append("count:").append(count); P$QjDu-
buff.append(",p:").append(p); x3P@AC$\
buff.append(",nump:").append(num); _kd |:,
buff.append(",results:").append Z\L@5.*ydE
H|Nw)*.
(results); "5YdmBy
buff.append("}"); LBE".+
return buff.toString(); k|_2aQ02
} 35>}$1?-6
|.
6@-h~8
} f@{C3E dd
IF:M_
saT9%?4-