Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,}^FV~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Bl+PJ
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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 c`UizZ
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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 Upc_"mkI.
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分页支持类: M?qvI
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java代码: !!)NER-dv
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package com.javaeye.common.util; lG`%4}1
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import java.util.List; g7v(g?
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publicclass PaginationSupport { 4@9xq<<5
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publicfinalstaticint PAGESIZE = 30; 6&"GTK
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privateint pageSize = PAGESIZE; acow
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privateList items; mv#*%St5
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privateint totalCount; Z)<lPg!YAR
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privateint[] indexes = newint[0]; (J.k\d
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privateint startIndex = 0; O_v*,L!
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public PaginationSupport(List items, int B|r'
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totalCount){ Lv<vMIr
setPageSize(PAGESIZE); C/q!!
setTotalCount(totalCount); tcJN`N
setItems(items); D/Py?<n-B
setStartIndex(0); 2~%^y6lR
} 9D7i>e%,;-
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public PaginationSupport(List items, int e. R9:
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totalCount, int startIndex){ 9`7>"[=P
setPageSize(PAGESIZE); di37
setTotalCount(totalCount); 1YtK+,mz
setItems(items); ~P'i
/*:
setStartIndex(startIndex); *eMMfxFl
} C40o_1g
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public PaginationSupport(List items, int %m-U:H.Vp
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totalCount, int pageSize, int startIndex){ @iN"]GFjS
setPageSize(pageSize); -]Q\G
setTotalCount(totalCount); $#E!/vVwD7
setItems(items); N{uVh;_
setStartIndex(startIndex); plM:7#eA
} -[[(Zx
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publicList getItems(){ wJh/tb=$o
return items; ?HeUU
} <,y> W!
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publicvoid setItems(List items){ Yw_!40`
this.items = items; ZWQ/BgKB
} E[<*Al+N
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publicint getPageSize(){ ^ U~QQ
return pageSize; 8k;il54#
} #gXxBM
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publicvoid setPageSize(int pageSize){ T@a|*.V
this.pageSize = pageSize; e/}4Pt
} 5t-,5
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publicint getTotalCount(){ ,(NN)Oj
return totalCount; zpZfsn!
} \} _,g
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publicvoid setTotalCount(int totalCount){ N! I$Qtr,
if(totalCount > 0){ R[OXYHu
this.totalCount = totalCount; L2OR<3*|Av
int count = totalCount / J M`[|"R%
Rx?ze(
pageSize; &d\ y:7
if(totalCount % pageSize > 0) *q+X?3
count++; d{Owz&PL
indexes = newint[count]; X!m
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for(int i = 0; i < count; i++){ ],Yy)<e.
indexes = pageSize * /@I`V?Q!a
6"R'z#{OF
i; %< `D'V@
} 9dWz3b1[]
}else{ 4eJR=h1
this.totalCount = 0; L$,yEMCe
} W||&Xb
} Nnq1&j"m
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publicint[] getIndexes(){ (%mV,2|:20
return indexes;
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} ]J@-,FFC
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publicvoid setIndexes(int[] indexes){ Fm*npK
this.indexes = indexes; QNH3\<IS
} w^U{e
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publicint getStartIndex(){ %Aqf=R_^
return startIndex; $lq.*UQ;0
} $m A2AI
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publicvoid setStartIndex(int startIndex){ b`@J"E}
if(totalCount <= 0) 7VL|\^Y `q
this.startIndex = 0; Ej1<T,w_
elseif(startIndex >= totalCount) Qqs1%u;e8
this.startIndex = indexes Sa
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[indexes.length - 1]; 5{bc&?"
elseif(startIndex < 0) O8SE)R~
this.startIndex = 0; _
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else{ SZ}=~yoD(
this.startIndex = indexes k81%$E
5DVYHN9c|
[startIndex / pageSize]; b` va\'&3
} ~]q>}/&YLo
} n4y]h
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publicint getNextIndex(){ 8KYI Hw
int nextIndex = getStartIndex() + 8QoxU"
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pageSize; gY8$Rk
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if(nextIndex >= totalCount) A+3SLB
return getStartIndex(); ~clX2U8u`
else Rc
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return nextIndex; !?=U{^|7y
} _^NyLI%
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publicint getPreviousIndex(){ FSn3p}FVa
int previousIndex = getStartIndex() - 6)7cw8^
gn&Zt}@[
pageSize; imeE&
if(previousIndex < 0)
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return0; kguZ AO6
else gu+zfvkcY
return previousIndex;
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} |<5F08]v
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} `j(._`8%a
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抽象业务类 X%3?sH
java代码: H!&_Tv[
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/** oQObr
* Created on 2005-7-12 O9p s?{g
*/ m\X\Xp~A
package com.javaeye.common.business; J=k=cFUX
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import java.io.Serializable; -Ep#q&\
import java.util.List; E6ZkO/
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import org.hibernate.Criteria; 23WrJM!2N
import org.hibernate.HibernateException; .7
0
import org.hibernate.Session; }\Rmwm-
import org.hibernate.criterion.DetachedCriteria; &9fQW?Czs
import org.hibernate.criterion.Projections; ir/uHN@
import doOuc4
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org.springframework.orm.hibernate3.HibernateCallback; <r.QS[:h
import )*>wa%[-q
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org.springframework.orm.hibernate3.support.HibernateDaoS \yC /OLXq
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upport; W(R~K -
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import com.javaeye.common.util.PaginationSupport; {
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public abstract class AbstractManager extends kM{8zpn
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HibernateDaoSupport { Rd5_{F
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privateboolean cacheQueries = false; }b&lHr'Uw
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privateString queryCacheRegion; OtmDZ.t;`
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publicvoid setCacheQueries(boolean Z)M
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cacheQueries){ ,1#? 0q
this.cacheQueries = cacheQueries; X<$Tn60,
} @,TIw[p
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publicvoid setQueryCacheRegion(String lz~^*\ F
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queryCacheRegion){ IBo
this.queryCacheRegion = <D ~hhGb
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queryCacheRegion; W.MZN4=
} _huJ*W7lR
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publicvoid save(finalObject entity){ E|"SMA,
getHibernateTemplate().save(entity); KE~Q88s
} YHQ]]#'
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publicvoid persist(finalObject entity){ CTRUr"
getHibernateTemplate().save(entity); r)pt(*KHo
} %m\:AK[}
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publicvoid update(finalObject entity){ 95z|}16UK
getHibernateTemplate().update(entity); 1>j,v+
} *k62Qz3
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publicvoid delete(finalObject entity){ *VsVCUCz5*
getHibernateTemplate().delete(entity); RI&O@?+U
} P'lnS&yA
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publicObject load(finalClass entity, 9 A ?{}c
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finalSerializable id){ t.28IHJ
return getHibernateTemplate().load WJhTU@'
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(entity, id); e"%TU
} gHBv Q1g
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publicObject get(finalClass entity, :^3 )[.m
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finalSerializable id){ cQ j`W
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return getHibernateTemplate().get 1"ZtE\{
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(entity, id); LBCH7@V1yR
} >nghFm
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publicList findAll(finalClass entity){ :}zyd;Rc
return getHibernateTemplate().find("from 0]|`*f&p;
@F<{/|P
" + entity.getName()); UJI2L-;Ul
} ?l/6DT>e
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publicList findByNamedQuery(finalString O D}RnKL
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namedQuery){ **hQb$
return getHibernateTemplate g%f5hy
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().findByNamedQuery(namedQuery); &L+uu',M0c
} \Mg_Q$
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publicList findByNamedQuery(finalString query, <b zzbR[F
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finalObject parameter){ z!"vez
return getHibernateTemplate 4|`>}Nu
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().findByNamedQuery(query, parameter);
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} Q6qW?*Y
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publicList findByNamedQuery(finalString query, \sAaVdZJH(
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finalObject[] parameters){ {=ox1+d
return getHibernateTemplate W7qh1}_%
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().findByNamedQuery(query, parameters); A9MM^jV8
} <giBL L!
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publicList find(finalString query){ ^9[Q;=R
return getHibernateTemplate().find eIkKsgr>
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(query); X/~uF9a'<
} b"h'7 C/
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publicList find(finalString query, finalObject $y8-JR~
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parameter){ t5-O-AI[b{
return getHibernateTemplate().find vV}w>Ap[
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(query, parameter); 7=CkZ&(?
} pmNy=ZXx
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public PaginationSupport findPageByCriteria AoS7B:T;!
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(final DetachedCriteria detachedCriteria){ 7Z< ~{eD,
return findPageByCriteria $d?W1D<A
G\@pg;0|y
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7)lEZJK&T
} m-Eh0Zl>Z
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public PaginationSupport findPageByCriteria K;RH,o1
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(final DetachedCriteria detachedCriteria, finalint dkC[SG`
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startIndex){ MVYd\)\o
return findPageByCriteria DzAZv/h76
;V}:0{p
(detachedCriteria, PaginationSupport.PAGESIZE, {~U3|_"[pX
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startIndex); v-{g
} `L'g<VK;
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public PaginationSupport findPageByCriteria )E}v~GW.+
=>$)F 4LW
(final DetachedCriteria detachedCriteria, finalint ]||b2[*
q)k:pQ
pageSize, KNVu[P)rv
finalint startIndex){ %_OjmXOfe
return(PaginationSupport) ^#Ii=K-[^
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getHibernateTemplate().execute(new HibernateCallback(){ T}#iXgyx
publicObject doInHibernate Hb)FeGsd).
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(Session session)throws HibernateException { c7e,lgG-
Criteria criteria = {X!OK3e
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detachedCriteria.getExecutableCriteria(session); r]3-}:vU
int totalCount = ]@{Lx>Oh"
my?Ly(#
((Integer) criteria.setProjection(Projections.rowCount IVR%H_uz
23}` e
()).uniqueResult()).intValue(); jf9+H!?^N
criteria.setProjection 5;a*Xf%V
IO%kXF.[
(null); #EPC]jFk
List items = -YA,Stc-
/I%z7f91O
criteria.setFirstResult(startIndex).setMaxResults n4K!Wv&u
\Vyys[MMY8
(pageSize).list(); #<*Vc6pC
PaginationSupport ps = AC,RS7
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new PaginationSupport(items, totalCount, pageSize, =Hi@q
"
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startIndex); Z8|<%1Kge
return ps;
}v ZOPTP
} *1)>He$qL
}, true); GJ ^c^`
} ./YR8 #,
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public List findAllByCriteria(final @>2pY_
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DetachedCriteria detachedCriteria){ 5hrI#fpOR
return(List) getHibernateTemplate H"A%mrb
>e;-$$e
().execute(new HibernateCallback(){ qRt! kWW
publicObject doInHibernate +?_!8N8
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(Session session)throws HibernateException { @62T:Vl
Criteria criteria = '}.Yf_
/R#zu_i
detachedCriteria.getExecutableCriteria(session); ">H*InF
return criteria.list(); gaF6j!p
} o<G 9t6~
}, true); At Wv9
} @*6fEG{,q
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public int getCountByCriteria(final g) X3:=['
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DetachedCriteria detachedCriteria){ 1dH|/9
Integer count = (Integer) eADCT
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getHibernateTemplate().execute(new HibernateCallback(){ %8'8XDq^8
publicObject doInHibernate VBhUh~:Om
oTw!#Re)
(Session session)throws HibernateException { F? #3
Criteria criteria = [|(|"dh@^H
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detachedCriteria.getExecutableCriteria(session); <FT7QO$I
return yJA~4
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criteria.setProjection(Projections.rowCount S$mv(C
!=[Y yh
()).uniqueResult(); q}{E![ZTu
} ) c@gRb~
}, true); tLE8+[
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return count.intValue(); ? x)^f+:9|
} ! ]4u"e
} zoq;3a5cqB
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用户在web层构造查询条件detachedCriteria,和可选的 ,.,8-In^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {:X'9NEE
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PaginationSupport的实例ps。 DX_mrG
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ps.getItems()得到已分页好的结果集 _4S^'FDo
ps.getIndexes()得到分页索引的数组 VPMu)1={:p
ps.getTotalCount()得到总结果数 G%W9?4_K
ps.getStartIndex()当前分页索引 RY-iFydPc
ps.getNextIndex()下一页索引 R5HT
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ps.getPreviousIndex()上一页索引 WgNA%.|,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 THrLX;I
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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 k8gH#ENNK
&#p1ogf:
一下代码重构了。 s^kG]7
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我把原本我的做法也提供出来供大家讨论吧: J/1kJ@5
]H1mj#EWU
首先,为了实现分页查询,我封装了一个Page类: #xIg(nG
java代码: yD9enYM
3",gjXmBu
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/*Created on 2005-4-14*/ ni;_Un~
package org.flyware.util.page; K~(RV4oF8B
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/** ~ k*]Z8Z
* @author Joa [ 8Ohg
* /!6 'K
*/ 66=[6U9 *
publicclass Page { %4~"$kE
Jqoo&T")
/** imply if the page has previous page */ Yh<F-WOo2
privateboolean hasPrePage; )nm+_U
LU3pCM{
/** imply if the page has next page */ h&"9v~
privateboolean hasNextPage; V)$!WPL@
EP>u% ]#
/** the number of every page */ t{k:H4
privateint everyPage; !I7$e&Uz@
j\}.GM'8
/** the total page number */ Y\
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privateint totalPage; Aztrq
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/** the number of current page */ J8'"vc} =
privateint currentPage; .f~9IAXP`
=*UK!y?n
/** the begin index of the records by the current ;dIk$_FN
EC?5GNGT,
query */ /T _M't@j
privateint beginIndex; %i9S"
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~j!n`#.\
/** The default constructor */ P\"kr?jZP
public Page(){ v93b8/1
{&1L &f<
} cy%M$O|hX5
_}[
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/** construct the page by everyPage }?[];FB
* @param everyPage 6h9(u7(-N
* */ ]E9iaq6Z
public Page(int everyPage){ |MNSIb&,W
this.everyPage = everyPage; rto?*^N?
} e@3SF
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/** The whole constructor */ := V?;
public Page(boolean hasPrePage, boolean hasNextPage, k+J3Kl09hM
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int everyPage, int totalPage, r-qe7K@p
int currentPage, int beginIndex){ J/]%zwDwS
this.hasPrePage = hasPrePage; %"
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this.hasNextPage = hasNextPage; }dc0ZRKgx
this.everyPage = everyPage; A
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this.totalPage = totalPage; 6wlLE5
this.currentPage = currentPage; &h:4TaD
this.beginIndex = beginIndex; Bii'^^I;?
} ()lgd7|+
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/** 6,t6~Uo/
* @return m?S;sew@5
* Returns the beginIndex. rm-d),Zt
*/ M=,pn+}y>
publicint getBeginIndex(){ XYU5.
return beginIndex; V.B@@ ;
} 6uE20O<z]
C'#KTp4!1
/** 0["93n}r
* @param beginIndex kpgvAKyx
* The beginIndex to set. 9p_?t'&>q
*/ @a8lF$<
publicvoid setBeginIndex(int beginIndex){ 0|e[o"
this.beginIndex = beginIndex; bQ*yXJ^8
} 4\z@Evm
IO)Y0J>x
/** *7Vb([x4;
* @return BA\aVhmx
* Returns the currentPage. t<rIg1
*/ F5?S8=i
publicint getCurrentPage(){ :8b'HhjM
return currentPage; #Y5k/NPg
} oU=vl!\J
Y"FV#<9@7E
/** /pMOinuO
* @param currentPage 66val"^W
* The currentPage to set. /k'7j*t Z
*/ )+
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publicvoid setCurrentPage(int currentPage){ H(y`[B,}*
this.currentPage = currentPage; \%7*@&
} /,G `V
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/** xpdpD
* @return 1T|f<ChIF<
* Returns the everyPage. eB0exPz%
*/ <8WFaP3,
publicint getEveryPage(){ vr;`h/
return everyPage; )n&hO_c/
} 56AC%_ g>
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/** ?L<B]!9HZt
* @param everyPage ~& -h5=3
* The everyPage to set. 5RPG3ppS
*/ sVyV|!K
publicvoid setEveryPage(int everyPage){ r;Sk[Y5#
this.everyPage = everyPage; u=:f%l
} /+*"*Br/
+bumWOQ'
/** }40T'y
* @return '| i?-(f)
* Returns the hasNextPage. 0B.Gt&Oal
*/ uj.i(Us
publicboolean getHasNextPage(){ P%|~Ni_BTX
return hasNextPage; /A{ Zf'DI
} ]N'3jf`W
UhH#>2r_
/** HA'~1$#z
* @param hasNextPage jOGdq;|
* The hasNextPage to set. kmC@\xTp
*/ B4.:
9Od3
publicvoid setHasNextPage(boolean hasNextPage){ %bnXZA2Sx
this.hasNextPage = hasNextPage; svpQ.Q
} H<d~AurX)J
7d;|?R-8D
/** m. pm,
* @return P&0eu
* Returns the hasPrePage. w/|&N>ZOx
*/ K6DN>0sY
publicboolean getHasPrePage(){ 5Zq
hyv=
return hasPrePage; %]+R>+
} "3RFyi
fZiAl7b!
/** J?O0ixU
* @param hasPrePage 5/"$_7"{a
* The hasPrePage to set. (p>|e\(]0
*/ R XCn;nM4
publicvoid setHasPrePage(boolean hasPrePage){ Znb={hh
this.hasPrePage = hasPrePage; C]!2
} 9q'&tU'a=c
kY)Vr3uGA
/** i$NlS}W
* @return Returns the totalPage. ( d_z\U7l
* ](Fey0@
*/ /DAR'9@h
publicint getTotalPage(){ ,@ '^3u
return totalPage; G*9(O:
} !
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kX8C'D4 gX
/** ZJ3g,dc
* @param totalPage hl1IG
!
* The totalPage to set. E@GYl85fI
*/ "# *W#ohVA
publicvoid setTotalPage(int totalPage){ #8Bh5L!SJ1
this.totalPage = totalPage; w<(ubR %$
} uSfHlN4l
!1l~UB_
} httywa^
v]k-xn|$j
s|\)Y*B`
1'&.6{)P
Z|t=t"6"
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 LdZVXp^
0he3[m}Nr
个PageUtil,负责对Page对象进行构造: D40 vCax^J
java代码: 3"x_Y
_ $a3lR
zxn|]PbS
/*Created on 2005-4-14*/ ep6+YK:cn
package org.flyware.util.page; flCT]ZR
Yc7YNC.
import org.apache.commons.logging.Log; fl-J:`zyyZ
import org.apache.commons.logging.LogFactory; C5~~$7k0
;FqmZjm
/** +[G9PP6
* @author Joa qHk{5O3
* w~@"r#-
*/ 2 5 \S>
publicclass PageUtil { .8YxEnXw)(
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privatestaticfinal Log logger = LogFactory.getLog +(*HDa|
8 W
(PageUtil.class); gKh*q.
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/** 19$A!kH\
* Use the origin page to create a new page /S]$Hu|
* @param page Ro<779.Gn\
* @param totalRecords \B#tB?rA
* @return &l+Qn'N
*/ 0x<ASfka
publicstatic Page createPage(Page page, int JK2{9#*
c,@Vz
7c
totalRecords){ ]^ R':YE
return createPage(page.getEveryPage(), uU^DYgs
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page.getCurrentPage(), totalRecords); }PI:O%N;
} I0mp [6
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/** `0Udg,KOs
* the basic page utils not including exception b<tV>d"Fv
<D|&)/#
handler mz0{eO
* @param everyPage f\
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* @param currentPage k{2Gq1S{
* @param totalRecords 33~MP;
* @return page ~:Rbd9IB
*/ 0z/*JVka
publicstatic Page createPage(int everyPage, int TnQ>v{Rx
P&Keslk
currentPage, int totalRecords){ Ll|-CY $
everyPage = getEveryPage(everyPage); .?u<|4jE6
currentPage = getCurrentPage(currentPage); iYr)Ao5X
int beginIndex = getBeginIndex(everyPage, lrE"phYk
TdPd8ig8{
currentPage); "}3sL#|z
int totalPage = getTotalPage(everyPage, PSJj$bt;<+
#&.Znk:@.f
totalRecords); toA}0MI(:
boolean hasNextPage = hasNextPage(currentPage, y_9\07va<
Gi)Vr\Q.
totalPage); "lt <$.
boolean hasPrePage = hasPrePage(currentPage); |"}rdOV)
iDDJJ>F26
returnnew Page(hasPrePage, hasNextPage, J_7w_T/
everyPage, totalPage, E`j' <#V!
currentPage, oL]uY5eZoe
BvP\c_
beginIndex); <6(0ZO%,C!
} 0BXr[%{`
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privatestaticint getEveryPage(int everyPage){ Un]wP`
return everyPage == 0 ? 10 : everyPage; ! t!4CY
} 2/+~h(Cc
@@H/q
privatestaticint getCurrentPage(int currentPage){ x+Yo#u22
return currentPage == 0 ? 1 : currentPage; yhKH}
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} uUjjAGZ
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privatestaticint getBeginIndex(int everyPage, int |YLja87
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currentPage){ Gor9&aJ1
return(currentPage - 1) * everyPage; $2W#'_K+
} syr0|K[
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privatestaticint getTotalPage(int everyPage, int SA'g`
ug,AvHEnB
totalRecords){ Mst%]@TG
int totalPage = 0; }-tJ .3Zw
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if(totalRecords % everyPage == 0) WHx#;
totalPage = totalRecords / everyPage; $TK*w8@:
else brTNwRze
totalPage = totalRecords / everyPage + 1 ; H|aFs.S EQ
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return totalPage; _o9axBJs
} ?jR#txR
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privatestaticboolean hasPrePage(int currentPage){ x:-NTW
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return currentPage == 1 ? false : true; :Fhk$?/r
} h2'6W)
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privatestaticboolean hasNextPage(int currentPage, _jX,1+M
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int totalPage){ 5=V"tQ&d9U
return currentPage == totalPage || totalPage == 9<3( QR
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0 ? false : true; Osz=OO{
} #[bosb!R
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} oO;L l?~
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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。 K\ Wzh;
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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 x"Ll/E)\v]
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做法如下: _xAru9=n^
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 kL zjK]4 *
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的信息,和一个结果集List: KGDN)@D
java代码: O^\:J2I(
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/*Created on 2005-6-13*/ (ORbhjl
package com.adt.bo; .=YV
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import java.util.List; +FNGRL
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import org.flyware.util.page.Page; [GbrKq(
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/** ,JI] Eij^
* @author Joa #8XmOJ"W3k
*/ 1$DcE>
publicclass Result { oC"
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private Page page; a)W|gx6Y
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private List content; pF6u3]
*
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/** "tl{HM5u
* The default constructor JjZB!Lg=
*/ vFHeGq70j
public Result(){ `=;}I@]zj)
super(); r]LP=K1
} U{dK8~
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/** >3g`6d
* The constructor using fields hAUP#y@:H:
* W\j'8^kI9
* @param page Ru
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* @param content #rW-jW=A
*/ \V 'fB5
public Result(Page page, List content){ VEa"^{,w
this.page = page; Ag T)J
this.content = content; Mh3.GpS
} ?IeBo8
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/** Z[[*:9rY|
* @return Returns the content. '9]?jkl
*/ DCa[?|Y
publicList getContent(){ i5(qJ/u
return content; .qe+"$K'n
} 3VU4E|s>
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/** mKTF@DED
* @return Returns the page. ;fV"5H)U\
*/ d. d J^M
public Page getPage(){ \<9aS Y'U
return page; R-$w*=Y
} ]UIN4E
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/** v2rzHzFU
* @param content 5f_x.~ymA
* The content to set. 6t!=k6`1
*/ ]Ls T
public void setContent(List content){ % dFz[b
this.content = content; ?v,c)
} tMdSdJ8
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/** ?$)a[UnqX
* @param page A/9<} m
* The page to set. JkR%o
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*/ noaR3)
publicvoid setPage(Page page){ ]~$@x=p2e
this.page = page; ~:,}?9
} _Cf:\Xs
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} nGTGX
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**-rPonM[
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2. 编写业务逻辑接口,并实现它(UserManager, RJ3uu NK7
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UserManagerImpl) =KO]w9+\
java代码: KiMlbF.~V
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/*Created on 2005-7-15*/ iiuT:r
package com.adt.service; x]Nx,tt
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import net.sf.hibernate.HibernateException; oFyB-vpYQV
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import org.flyware.util.page.Page; ;L",K?6#
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import com.adt.bo.Result; {B#w9>'b
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/** k5%)
* @author Joa S_*Gv O
*/ rpEIDhHv
publicinterface UserManager { lO9Ixhf~iu
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public Result listUser(Page page)throws |$\1E+
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HibernateException; ,;MUXCC'
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} 2N(Z^
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java代码: Xsn M}
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/*Created on 2005-7-15*/ }#~E-N3x
package com.adt.service.impl; v 9G~i
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import java.util.List; -#<{3BJTrz
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import net.sf.hibernate.HibernateException; SG~HzQ\%
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import org.flyware.util.page.Page; V_^pPBa
import org.flyware.util.page.PageUtil; [T'[7Z
c#?~1@=
import com.adt.bo.Result; 1H%p|'FKA
import com.adt.dao.UserDAO; K)1Lg?j
import com.adt.exception.ObjectNotFoundException; aox@- jyr
import com.adt.service.UserManager; TWRnty-C
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/** WAuT`^"u
* @author Joa DIP%*b#l$\
*/ s9Tn|Pm+!\
publicclass UserManagerImpl implements UserManager { ?|NsaW
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private UserDAO userDAO; j,%i.[8S
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/** B`nI]_
* @param userDAO The userDAO to set. qxyY2&
*/ 3z#>1HD$
publicvoid setUserDAO(UserDAO userDAO){ ut]&3f''
this.userDAO = userDAO; %WP[V{,F
} C\Ob!sv%H
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/* (non-Javadoc)
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* @see com.adt.service.UserManager#listUser W4#DeT
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(org.flyware.util.page.Page) MkdC*|
*/ UH7?JF-D
public Result listUser(Page page)throws %y_pF?2@q
03 iy[~Y2
HibernateException, ObjectNotFoundException { PktnjdFV
int totalRecords = userDAO.getUserCount(); p.MLKp-'
if(totalRecords == 0) KqBiF]Q
throw new ObjectNotFoundException >#;_Ebl@
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("userNotExist"); zLxuxf~4@
page = PageUtil.createPage(page, totalRecords); .;U?%t_7
List users = userDAO.getUserByPage(page); cJSwA&
returnnew Result(page, users); 9J_vvq`%`
} ?J+*i
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} s/3sOb}sA
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1 K^-tms
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询,接下来编写UserDAO的代码: G7GKO
3. UserDAO 和 UserDAOImpl: vUL@i'0&o
java代码: S@
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/*Created on 2005-7-15*/ $QT% -9&
package com.adt.dao; E+ XR[p
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import java.util.List; u#V;
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import org.flyware.util.page.Page; zT!.5qd
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import net.sf.hibernate.HibernateException; fI.X5c>WK
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/** |1<B(iB'{/
* @author Joa
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/
*/ ljg6uz1v%
publicinterface UserDAO extends BaseDAO { z>=;Xe8P8n
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publicList getUserByName(String name)throws W=#jtU`:5
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HibernateException; :a=]<_*x
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publicint getUserCount()throws HibernateException; sP9{tk2K
. 7Pp'-hK
publicList getUserByPage(Page page)throws DU5rB\!.~
zQGj,EAM}
HibernateException; qM>Dt
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} or)fx/ %h
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java代码: wSALK)T1{
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/*Created on 2005-7-15*/ ^R+CkF4l l
package com.adt.dao.impl; ZxDh!_[s
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import java.util.List; '1G0YfG}n
hig t(u
import org.flyware.util.page.Page; sI#h&V,9
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import net.sf.hibernate.HibernateException; I'<sJs*p
import net.sf.hibernate.Query; G he@m6|D
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import com.adt.dao.UserDAO; 3m~3l d
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/** $ Fy)+<
* @author Joa Aq$o&t
*/ [2
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public class UserDAOImpl extends BaseDAOHibernateImpl "/hLZl
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implements UserDAO { bvJ*REPL?
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/* (non-Javadoc) 1aUu:#c
* @see com.adt.dao.UserDAO#getUserByName #yCnM]cEn
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fCB}
(java.lang.String) m
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*/ tU8aPiUl
publicList getUserByName(String name)throws e.|t12)L "
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HibernateException { pQm-Hr78j
String querySentence = "FROM user in class v1NFz>Hx
,` $2
com.adt.po.User WHERE user.name=:name"; (<|1/^~=
Query query = getSession().createQuery q}&+{dN\1
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(querySentence); L[:M[,?=`
query.setParameter("name", name); .4=A:9
return query.list(); d%1Vby
} `_{,4oi
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/* (non-Javadoc) u/`x@u
* @see com.adt.dao.UserDAO#getUserCount() i_$?sg#=yk
*/ 2bpFQ8q
publicint getUserCount()throws HibernateException { S.owVMQ
int count = 0; <FvljKuq+
String querySentence = "SELECT count(*) FROM 0B5d $0
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user in class com.adt.po.User"; ^;EwZwH[
Query query = getSession().createQuery O(T6Y80pU
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(querySentence); mldY/;-H!1
count = ((Integer)query.iterate().next (`f)Tt=`
("J_< p
()).intValue(); {6wy}<ynC+
return count; 9:Z|Z?>?
} aS+i`A :a
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/* (non-Javadoc) j)jt&Gg'
* @see com.adt.dao.UserDAO#getUserByPage x=Ez hq]X
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(org.flyware.util.page.Page) j<vU[J+gx~
*/ 3^F1 hCB
publicList getUserByPage(Page page)throws H4e2#]*i7
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HibernateException { wq#'o9s,
String querySentence = "FROM user in class =ZARJ40L
3>^S6h}o
com.adt.po.User"; l{3ZN"`I
Query query = getSession().createQuery jTok1k
l @r`NFWD@
(querySentence); RgVg~?A@
query.setFirstResult(page.getBeginIndex()) '/F~vSQsR
.setMaxResults(page.getEveryPage()); o@|kq1m8
return query.list(); %U&ztvR0C
} StMvz~
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} 5R#:ALwX:
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至此,一个完整的分页程序完成。前台的只需要调用 3;EBKGg|
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userManager.listUser(page)即可得到一个Page对象和结果集对象 au7@- _
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的综合体,而传入的参数page对象则可以由前台传入,如果用 z-h7v5i"
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webwork,甚至可以直接在配置文件中指定。 bKPjxN?!9
k%({<