Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 |Q>IrT
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 tLmTjX .6
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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 4KrL{Z+}
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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 3+bt~J0
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分页支持类: Af{"pzY
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java代码: vr^qWn
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package com.javaeye.common.util; Na Cy@
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import java.util.List; H>@+om
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publicclass PaginationSupport { CJI~_3+K
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publicfinalstaticint PAGESIZE = 30; ;9g2?-svw
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privateint pageSize = PAGESIZE; 4E?Oky#}-
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privateList items; S21,VpW\
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privateint totalCount; POR\e|hRT]
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privateint[] indexes = newint[0]; e?f IXk~b
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privateint startIndex = 0; 7=, ; h
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public PaginationSupport(List items, int lb1Xsgm{
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totalCount){ s"?3]P
setPageSize(PAGESIZE); b>9>uC@J15
setTotalCount(totalCount); }:#P)8/v>%
setItems(items); =mmWl9'mJ
setStartIndex(0); ,6W>can
} HUO j0T
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public PaginationSupport(List items, int #cLBQJq
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totalCount, int startIndex){ +d-NL?c
setPageSize(PAGESIZE); OK
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setTotalCount(totalCount); 76` .Y
setItems(items); ,,|^%Ct']
setStartIndex(startIndex); ei5~&
} 4nz 35BLr
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public PaginationSupport(List items, int YT8F#t8
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totalCount, int pageSize, int startIndex){ ;ovP$ vl>
setPageSize(pageSize); NW)1#]gg%
setTotalCount(totalCount); H7+,*
setItems(items); &
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setStartIndex(startIndex); ^y4Z+Gu[
} /|&*QLy
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publicList getItems(){ 0Fr?^3h
return items; Q)z8PQl O
} BDZ?Ez\Sg
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publicvoid setItems(List items){ RY*U"G0#w
this.items = items; $,fX:x
} EDs\,f}
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publicint getPageSize(){ 5 + MS^H
return pageSize; $
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} 8SS|a
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publicvoid setPageSize(int pageSize){ HiJE}V;Vq
this.pageSize = pageSize; E q+_&Wk
} 7i1q wRv
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publicint getTotalCount(){ @gXx1hEg
return totalCount; b*Q&CL
} r-/`"j{O!
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publicvoid setTotalCount(int totalCount){ ]:/Q]n^
if(totalCount > 0){ 01(AK% e
this.totalCount = totalCount; *siFj
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int count = totalCount / -+-_I*(
ges J/I
pageSize; &XUiKnNW
if(totalCount % pageSize > 0) tIS<U(N;
count++; QnX(V[
indexes = newint[count]; *EwR!L*
for(int i = 0; i < count; i++){ K)k<Rh[<
indexes = pageSize * VTHH&$ZNq
s=/v';5J2!
i; 57'4ljvYi
} 2jCf T>`3
}else{ KdbHyg<4
this.totalCount = 0; H~z`]5CN
} mXfXO*Cnp
} VBcPu
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publicint[] getIndexes(){ {U !g.rh
return indexes; 1D!<'`)AY
} 8BNi1Qn$
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publicvoid setIndexes(int[] indexes){ LvYB7<zk>
this.indexes = indexes; -!]ZMi9
} ?p8_AL'RS
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publicint getStartIndex(){ 5rZ
return startIndex; t}tEvh
} WQO) =n
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publicvoid setStartIndex(int startIndex){ /fV;^=:8c
if(totalCount <= 0) q?/a~a
this.startIndex = 0; "|KP'<8%
elseif(startIndex >= totalCount) w_u\sSQ`!
this.startIndex = indexes OJy#w{4
3>VL}Ui}
[indexes.length - 1]; CF5`-wj/#
elseif(startIndex < 0) @cB$iP=Z4
this.startIndex = 0; *%@h(js
else{ =+d?x56
this.startIndex = indexes Vj>8a)"B5a
sZF6h=67D
[startIndex / pageSize]; gCY';\f!
} v0jgki4t
} [QT#Yf0
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publicint getNextIndex(){ I`4*+a'q&
int nextIndex = getStartIndex() + q{;:SgZ
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pageSize; l0A&9g*l2
if(nextIndex >= totalCount) QGmn#]w\\
return getStartIndex(); p0<\G
else <B8!.|19
return nextIndex; 0b(N^$js'
} fkNbS
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publicint getPreviousIndex(){ 3WIk
int previousIndex = getStartIndex() - O/(xj2~$J
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pageSize; 3n}?bY8@5_
if(previousIndex < 0) yd`mG{Z
return0; '$zIbQ:
else RQu(Wu|m.
return previousIndex; O#S.n#{
} Pw!MS5=r
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} -Wi` G
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抽象业务类 HBx=\%;n
java代码: K?$^@N
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/** OMg<V
* Created on 2005-7-12 >_ 2dvg=U
*/ /HRFAqep
package com.javaeye.common.business; ThbGQ"/
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import java.io.Serializable; naznayy
import java.util.List; 2'MZ s]??w
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import org.hibernate.Criteria; Is?La
import org.hibernate.HibernateException; 9ahWIO%
import org.hibernate.Session; ^V Zk+'4
import org.hibernate.criterion.DetachedCriteria; [!]2djc
import org.hibernate.criterion.Projections; L"*/:$EJL.
import O~K>4ax
gi
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org.springframework.orm.hibernate3.HibernateCallback; !6Mo]xh
import O2dW6bt
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org.springframework.orm.hibernate3.support.HibernateDaoS JKGe"
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upport; GKc`xIQ
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import com.javaeye.common.util.PaginationSupport; q 2:6QM&
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public abstract class AbstractManager extends \%N!5>cZ{
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HibernateDaoSupport { $F+ L Ds
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privateboolean cacheQueries = false; A*P|e-&Q8
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privateString queryCacheRegion; 74k dsgQf
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publicvoid setCacheQueries(boolean @>>~CZ`l
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cacheQueries){ JKmIvZ)8
this.cacheQueries = cacheQueries; r{I%
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} x!58cS*
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publicvoid setQueryCacheRegion(String ly_HWuFJ3
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queryCacheRegion){ Bj-:#P@
this.queryCacheRegion = !sW(wAy?o
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queryCacheRegion; [o+q>|q
} y0.8A-2:
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publicvoid save(finalObject entity){ c*L\_Vx+
getHibernateTemplate().save(entity); iq( E'`d
} 6){]1h"
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publicvoid persist(finalObject entity){ nWYN Np?h
getHibernateTemplate().save(entity); QD*35Y!d
} [dIXR
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publicvoid update(finalObject entity){ ll.N^y;a
getHibernateTemplate().update(entity); p(`6hWx
} ~T,c"t2
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publicvoid delete(finalObject entity){ eMY<uqdw
getHibernateTemplate().delete(entity); ah0`KxO]
} *>2W#D)b=
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publicObject load(finalClass entity, OJ5#4qJ[
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finalSerializable id){ > $7v
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return getHibernateTemplate().load f"SD/]q-
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(entity, id); ^c4@(]v'G
} :^WKT
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publicObject get(finalClass entity, ?+W9az]+
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finalSerializable id){ IIF]/Ek]
return getHibernateTemplate().get se>8 Z4
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(entity, id); k_5L4c:"
} q?DTMKx
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publicList findAll(finalClass entity){ 'o+L41
return getHibernateTemplate().find("from ^l=!JP=M=
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" + entity.getName()); -$jEfi4I
} ``Dq
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publicList findByNamedQuery(finalString 6dN7_v)
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namedQuery){ '\ey<}?5V
return getHibernateTemplate A1D^a,
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().findByNamedQuery(namedQuery); }v*G_}^
} 4@n1Uk
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publicList findByNamedQuery(finalString query, :'3XAntZA
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finalObject parameter){ w?wG(+X7
return getHibernateTemplate Vp*KfS]
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().findByNamedQuery(query, parameter); uRRQyZ
} `V]5 sE]G
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publicList findByNamedQuery(finalString query, zHL@i0>^
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finalObject[] parameters){ PQnF
return getHibernateTemplate q[`]D7W
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().findByNamedQuery(query, parameters); BJB^m|b)
} D2!X?"[P
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publicList find(finalString query){ G!W[8UG
return getHibernateTemplate().find E^lvbLh'
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(query); Z
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} gp^5#
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publicList find(finalString query, finalObject C8e
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parameter){ K[Kh&`T
return getHibernateTemplate().find cc&axc7I
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(query, parameter); v'qG26
} Co9QW/'i
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public PaginationSupport findPageByCriteria V |/NB
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(final DetachedCriteria detachedCriteria){ :xD=`ib
return findPageByCriteria v!P b`LCqK
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); P 8>d6;o($
} V9(@Y
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public PaginationSupport findPageByCriteria X*39c
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(final DetachedCriteria detachedCriteria, finalint zj`v?#ET
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startIndex){ F\AX:
return findPageByCriteria &nkW1Ner9
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(detachedCriteria, PaginationSupport.PAGESIZE, LbG_ z =A
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startIndex); .0iQad&duh
} U.XNv-M
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public PaginationSupport findPageByCriteria ]Nl=wZ#`
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(final DetachedCriteria detachedCriteria, finalint mc_ch$r!
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pageSize, %D8ZO0J7H
finalint startIndex){ .k9{Yv0
return(PaginationSupport) 2
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getHibernateTemplate().execute(new HibernateCallback(){ !+4cqO
publicObject doInHibernate 079'(%
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(Session session)throws HibernateException { Xn,v]$M!
Criteria criteria = \X&H;xnC5
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detachedCriteria.getExecutableCriteria(session); T2 Y,U {
int totalCount = gO,25::")
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((Integer) criteria.setProjection(Projections.rowCount 2fS[J'-o
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()).uniqueResult()).intValue(); ~aOuG5XK
criteria.setProjection '+vA\(K
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(null); UkHY[M7;
List items = rEv*)W
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criteria.setFirstResult(startIndex).setMaxResults ~J8pnTY
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(pageSize).list(); psC
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PaginationSupport ps = !]fQ+ *X0g
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new PaginationSupport(items, totalCount, pageSize, d/|D<Sb[s
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startIndex); 6,LubZFD
return ps;
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} (_*5oj-
}, true); X*Dj[TD]
} W4U@%b do
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public List findAllByCriteria(final pY~,(s|Qb
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DetachedCriteria detachedCriteria){ T<@ cd|`
return(List) getHibernateTemplate Fxqp-}:
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().execute(new HibernateCallback(){ ~$ f;U
publicObject doInHibernate f{i8w!O"~
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(Session session)throws HibernateException { D?,#aB"
Criteria criteria = M$d%p6Cv
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detachedCriteria.getExecutableCriteria(session); ?N=m<fn
return criteria.list(); Cb@3M"1:
} drd/ jH&
}, true); )r
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} /c-r
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public int getCountByCriteria(final b}wC|\s
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DetachedCriteria detachedCriteria){ 3
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Integer count = (Integer) ym/fFm6h
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getHibernateTemplate().execute(new HibernateCallback(){ lz0TK)kuC
publicObject doInHibernate TO*BH^5R
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(Session session)throws HibernateException { $DC*i-}qFg
Criteria criteria = iy\nio`
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detachedCriteria.getExecutableCriteria(session); 3bd5FsI^pU
return \U?n+6 7g
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criteria.setProjection(Projections.rowCount ',4x$qe
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()).uniqueResult(); G633Lm`ri
} ;HBCUe<_
}, true); 7HJS.047
return count.intValue(); {d%&zvJnD
} Z!&Rr~i
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} [;.`,/
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用户在web层构造查询条件detachedCriteria,和可选的 %q322->Z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 f8<o8*`7
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PaginationSupport的实例ps。 %F9{EXJy
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ps.getItems()得到已分页好的结果集 $hVYTy~}
ps.getIndexes()得到分页索引的数组 ]PP:oriWl
ps.getTotalCount()得到总结果数 W Qzj[
ps.getStartIndex()当前分页索引 )Vk6;__
ps.getNextIndex()下一页索引 ";w}3+R
ps.getPreviousIndex()上一页索引 #W2[
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 RF!1oZ
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 %_aMl
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一下代码重构了。 R,!Q
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我把原本我的做法也提供出来供大家讨论吧: TfZ6F8|B
;#)mLsl
首先,为了实现分页查询,我封装了一个Page类: JH]K/sC>
java代码: xg{HQQ|TC
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B)h>8 {
/*Created on 2005-4-14*/ X0+fsf<H}
package org.flyware.util.page; ]Lqt(c
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/** xaKst
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* @author Joa SnTDLa
* %im#ww L%
*/ ,rwuy[Q8
publicclass Page { w[Ep*-yeI
npu6E;'l*
/** imply if the page has previous page */ V5GkP1L
privateboolean hasPrePage; }98>5%Uv
agOk*wH5
/** imply if the page has next page */ i!dv0|_
privateboolean hasNextPage; \H5Jk$*
*sfD#Bi]
/** the number of every page */ N<_Ko+VF
privateint everyPage; dow^*{fqZ
} i)$n(A)K
/** the total page number */ gglQU"=g{
privateint totalPage; dj[apuiF
7/X"z=Q^|
/** the number of current page */ Zq ot{s
privateint currentPage; N\1/JW+
I]J*BD#n.
/** the begin index of the records by the current /=#~
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query */ TQ1WVq
}*
privateint beginIndex; Lg`Jp&Kg
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/** The default constructor */ r<L#q)]
public Page(){ 22KI]$D#f
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} >n7["7HHk
z]$j7 dp
/** construct the page by everyPage vh>{_
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* @param everyPage {rkn q_;0
* */
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public Page(int everyPage){ af+}S9To
this.everyPage = everyPage; 8h?X!2Nq
} 3On
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/** The whole constructor */ Ew^ @Aq
public Page(boolean hasPrePage, boolean hasNextPage, dNVv4{S
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int everyPage, int totalPage, }Pg'
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int currentPage, int beginIndex){ ]?9[l76O7
this.hasPrePage = hasPrePage; %XXkVK`
this.hasNextPage = hasNextPage; O
rk
this.everyPage = everyPage; 1 2]fQkp
this.totalPage = totalPage; nY) .|\|i
this.currentPage = currentPage; de-0?6
this.beginIndex = beginIndex; 8tWE=8<
} ~%q7Vmk9
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/** j+748QAhh
* @return bGh0<r7R
* Returns the beginIndex. %7`d/dgR
*/ Wm6dQQ;Bj
publicint getBeginIndex(){ )hL^+Nn bR
return beginIndex; ^w6eWzI
} 5urE
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/** ixOw=!@
* @param beginIndex WhUa^
* The beginIndex to set. "jU
*/ bBE^^9G=Z
publicvoid setBeginIndex(int beginIndex){ }g,X5v?W
this.beginIndex = beginIndex; D$_8rHc\A
} &R\XUxI
6hbEO-(
/** C"T ,MH
* @return ?2~U2Ir]:
* Returns the currentPage. 8SD}nFQ
*/ =O^7TrM
publicint getCurrentPage(){ R/N<0!HZ
return currentPage; l:tpL(%
} V}`M<A6:
*t=i
/** '=%i,
* @param currentPage `QCD$=
* The currentPage to set. jCWu\Oe
*/ R;=6VH
publicvoid setCurrentPage(int currentPage){ 6bL"LM`s
this.currentPage = currentPage; lgG8!Ja
} .D@/y uV
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/** 6IF|3@yD
* @return [u\CD sX
* Returns the everyPage. px&=((Z7>
*/ H*qD: N
publicint getEveryPage(){ iy
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return everyPage; ]]V^:"ne
} anZIB
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/** ;^.9#B,<
* @param everyPage /2:Q6J
* The everyPage to set. cJq<9(
*/ |\p5mh
publicvoid setEveryPage(int everyPage){ anitqy#E
this.everyPage = everyPage; xXa#J)'
} bVmvjY4
fbL!=]A*3
/** Y_shy6"KH
* @return }I<N^j=/pO
* Returns the hasNextPage. Alh?0 Fk3)
*/ vj@V
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publicboolean getHasNextPage(){ ) hPVX()O!
return hasNextPage; s{% fi*
} 6(5c7R#
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/** @S}|Ccfc_
* @param hasNextPage InX{V|CW?
* The hasNextPage to set. /kb$p8!C".
*/ \1khyF'
publicvoid setHasNextPage(boolean hasNextPage){ ]*h&hsS0
this.hasNextPage = hasNextPage; |x[$3R1@
} r2)pAiTM*
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/** A@{ !:_55
* @return ][N) 2_^M
* Returns the hasPrePage. /op/g]O}
*/ RQJ9MGw
publicboolean getHasPrePage(){ .hnF]_QQ
return hasPrePage; .kzms
} 9w$7VW;
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/** {N@Y<=+:
* @param hasPrePage JbVi1?c
* The hasPrePage to set. 6A@Lj*:2m
*/ VG#$fRrZ
publicvoid setHasPrePage(boolean hasPrePage){ :EaiM J_=
this.hasPrePage = hasPrePage; {C, #rj
} ^8U6"O6|X
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/** A9.;>8!u
* @return Returns the totalPage. 92NC]_jw
* -q|*M:R
*/ | )S{(#k
publicint getTotalPage(){ |<7i|J
return totalPage; >T$7{
~
} EXH!glR[$
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/** 'NRN_c9
* @param totalPage G:){^Z?
* The totalPage to set. -<12~HKK::
*/ -{r!M(47
publicvoid setTotalPage(int totalPage){ f>b!-|
this.totalPage = totalPage; 5]Z] j[8Y
} 7a27^b
y>&VtN{E
} )<tzm'Rc
8:BQHYeJK
oO}>i0ax*
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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 gx&\Kw6HM
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个PageUtil,负责对Page对象进行构造: \_)02ZT:
java代码: ]r]+yM|
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/*Created on 2005-4-14*/ <m:4g
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package org.flyware.util.page; >J?jr&i
{[rO2<MkA#
import org.apache.commons.logging.Log; 939]8BERt
import org.apache.commons.logging.LogFactory; V&$ J;
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/** k^~@9F5k
* @author Joa QJniM"8v
* [k}dES#
*/ ktdz@f
publicclass PageUtil { /"g[Ay
4/ 0/#G#j
privatestaticfinal Log logger = LogFactory.getLog +YkmLD
v_[)FN"]Y.
(PageUtil.class); S]Sp Z8
&3+1D1"y/
/** _?*rtDzIM
* Use the origin page to create a new page 3/yt*cr
* @param page A;b=E[iv
* @param totalRecords :$+D
2*(
* @return 5 >0\e_V
*/ 0]/,m4a#n
publicstatic Page createPage(Page page, int 5?S{W
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totalRecords){ _wIBm2UO
return createPage(page.getEveryPage(), s,{RP0|
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page.getCurrentPage(), totalRecords); >}xAg7\^
} w50.gr7
OYQXi
/**
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* the basic page utils not including exception ~m009
f]{1ZU%4
handler /7!_un9
* @param everyPage >F_qa=t%[
* @param currentPage g>d7%FFn}
* @param totalRecords 1oXz[V
* @return page YqK+F=0
*/ -P IA;#Gs
publicstatic Page createPage(int everyPage, int BLsdx}
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currentPage, int totalRecords){ iqc4O
/
everyPage = getEveryPage(everyPage); )M&I)In'
currentPage = getCurrentPage(currentPage); *B)Jv9
int beginIndex = getBeginIndex(everyPage, U4
go8
O?+tY
y?
currentPage); mgJ]@s}9
int totalPage = getTotalPage(everyPage, ;C7BoHB9
Rh05W_?Js
totalRecords); ^59YfC<f
boolean hasNextPage = hasNextPage(currentPage, [esX{6,i
uyS^W'fF
totalPage); {7j6$.7J$&
boolean hasPrePage = hasPrePage(currentPage); )VV4HoH]8
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returnnew Page(hasPrePage, hasNextPage, ~_/<PIm
everyPage, totalPage, \Nh^Ig
currentPage, v '"1/% L
rH
[+/&w5
beginIndex); E.WNykF-
} 9Y!0>&o
DkF@XK0c3
privatestaticint getEveryPage(int everyPage){ DKaG?Y,*p
return everyPage == 0 ? 10 : everyPage; )U"D4j*p
} {d*qlztO
~(*co[_
privatestaticint getCurrentPage(int currentPage){ 6qmo
ZAg
return currentPage == 0 ? 1 : currentPage; 71}L#nQ
} F|h,a;2
TYmUPS$
privatestaticint getBeginIndex(int everyPage, int f0N)N}y
Q
KDb
currentPage){ w<8O=
return(currentPage - 1) * everyPage; 6@,'m
}
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r7wx?{~ 28
privatestaticint getTotalPage(int everyPage, int wXIe5
2s]]!{Z#
totalRecords){ f0HV*%8
int totalPage = 0; D!OG307P
+lk\oj$S+
if(totalRecords % everyPage == 0) H *z0xxa
totalPage = totalRecords / everyPage; 4P-'(4I)
else gpO_0U4lQ]
totalPage = totalRecords / everyPage + 1 ; nf+"vr}1
+Y>cBSO
return totalPage; leX7(Y;!a7
} k7Be'E
BKG
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privatestaticboolean hasPrePage(int currentPage){ oto
wvm
return currentPage == 1 ? false : true; zwniS6R1
} k8t Na@H
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privatestaticboolean hasNextPage(int currentPage, hD9'`SQ
sWpRX2{5,
int totalPage){ nw]e_sm
return currentPage == totalPage || totalPage == \CEnOq
6LF^[b/u
0 ? false : true; #u]_7/(</`
} }GU6Q|s[u[
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} HnKF#<
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yg]nS<K~4
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 D+vl%(g
51FK~5
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 [(.T%kJ
vSHIl"h
做法如下: NXG}0`QVT
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 OrKT~JQVC&
6jy n,GU
的信息,和一个结果集List: j}x
O34
java代码: e>i8 =U`;
{1-CfQ0
8
=QxE-)v
/*Created on 2005-6-13*/ +h\W~muR
package com.adt.bo; kAe-d
I!i#=
import java.util.List; z6>ZV6(d2^
#t9=qR~"
import org.flyware.util.page.Page; rc{[\1 -N
l4B O@
/** %imBGh
* @author Joa S|5lx7
*/ HDae_.
publicclass Result { .WPR}v,.Z
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private Page page; kl{OO%jZ
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private List content; v%PWr5]
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/** N=?kEX
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* The default constructor Xe^=(| M
*/ A%2M]];%X
public Result(){ !6fpMo
super(); =D"63fP1
} &.bR1wX
*U^\Mwp
/** "GC]E8&>H
* The constructor using fields PAWr1]DI
* Z=5}17kA
* @param page YPJx/@Z`
* @param content uP'w.nA&2
*/ -~GJ; Uw
public Result(Page page, List content){ %K f. F
this.page = page; Hn'2'Vu
this.content = content; y2hFUq
} hm} :Me$[)
v>cE59('0
/** k2,oyUT=S
* @return Returns the content. 1NHoIX
*/ ,8 -_=*
publicList getContent(){ $6x:aG*F
return content; p'c<v)ia
} qYiK bzy
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/** Pge }xKT
* @return Returns the page. 2P>za\
*/ 'L+BkE6+%
public Page getPage(){ $Aoqtz d\
return page; rZCAj
} `g:^KCGMM
;7=JU^@D@
/** s{EX ;
* @param content Am`A[rV0
* The content to set. >]08".ajS
*/ r^tXr[}
public void setContent(List content){ =
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this.content = content; VKJ~ZIO@A
} F^bQ-
xgw)`>p,W
/** *SG2k .$
* @param page )KhVUFS1
* The page to set. 5i-;bLm
*/ {gHscj;SM
publicvoid setPage(Page page){ eeTaF!W
this.page = page; ~I^[rP~
} (GOrfr
} "?(Fb_}i
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2. 编写业务逻辑接口,并实现它(UserManager, dX}dO)%m{
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UserManagerImpl) ){|Lh(
java代码: %1+~(1P
N}<U[nh'
v 5ddb)
/*Created on 2005-7-15*/ f<:SdtG5
package com.adt.service; w*kFtNBfU
h_"/@6
import net.sf.hibernate.HibernateException; G9":z|
s31_3?Vdf,
import org.flyware.util.page.Page; ;m:GUp^[
Zd/~ *ZA
import com.adt.bo.Result; &Zy=vk*
;4#8#;
/** k3h53QTmC
* @author Joa &{{f|o=u.
*/ eZkz 1j~
publicinterface UserManager { TUYl><F5v=
Jl9TMu!1]
public Result listUser(Page page)throws _rh.z_a7w
BCB/cBE
HibernateException; <a}|G1 h
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} ^G<M+RF2J
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F
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ri V/wN9C
{!bJ.O
l
java代码: t[ocp;Q
T mE4p
!h(0b*FUJ
/*Created on 2005-7-15*/ UimZ/\r
package com.adt.service.impl; zQfxw?~A
-T6%3>h
import java.util.List; >{=RQgGy
+Z0E?,Oz
import net.sf.hibernate.HibernateException; ~m&oa@*=y
Nn\\}R
import org.flyware.util.page.Page; I+Cmj]M s0
import org.flyware.util.page.PageUtil; 4
V*)0?oYE
n\DT0E]
import com.adt.bo.Result; 1k({(\>qq
import com.adt.dao.UserDAO; lY?d*qED
import com.adt.exception.ObjectNotFoundException; yKhzymS}T
import com.adt.service.UserManager; $X]v;B)J|
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/** pD/S\E0@t
* @author Joa H<?yG->
*/ Db:WAjU
publicclass UserManagerImpl implements UserManager { dPX>A4wp
IvSrJe[;
private UserDAO userDAO; WF0>R^SpZ
P6'I:/V
/** [=!MS?-G
* @param userDAO The userDAO to set. Ik)Q0_<a
*/ "&|2IA
publicvoid setUserDAO(UserDAO userDAO){ %/C[\wp81
this.userDAO = userDAO; 'FXZ`+r|
} _/\H3
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/* (non-Javadoc) O,6!`\N D
* @see com.adt.service.UserManager#listUser OaWq8MIZ-
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(org.flyware.util.page.Page) ( mMz]b5
*/ Z:Am\7 I
public Result listUser(Page page)throws KgSxF#
!!>G{
HibernateException, ObjectNotFoundException { [AwE
int totalRecords = userDAO.getUserCount(); !d_A? q'hN
if(totalRecords == 0) PdnK@a
throw new ObjectNotFoundException +y(h/NcQ
v[GHqZ
("userNotExist"); g/gLG:C
page = PageUtil.createPage(page, totalRecords); (#`o>G(
List users = userDAO.getUserByPage(page); YT8`Vz$+
returnnew Result(page, users); 8A_(]Q
} n\Nl2u& m
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} 9$i`B>C~
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1jVcL)szU
u>#'Y+7
询,接下来编写UserDAO的代码: N"y4#W(Z@
3. UserDAO 和 UserDAOImpl: 5Bk
java代码: voE c'JET
mD3#$E!A1
TXv#/@
/*Created on 2005-7-15*/ !y.7"G*
package com.adt.dao; 3\ed4D
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import java.util.List; !vw0Y,F&
{\I\4P
import org.flyware.util.page.Page; `!N?#N:b)
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import net.sf.hibernate.HibernateException; jRc#>;dN
Yw0@O1Cel
/** gX<C-y6o
* @author Joa C? S %fF
*/ *1Q?~
publicinterface UserDAO extends BaseDAO { GYO"1PM
s]UeDZ<a
publicList getUserByName(String name)throws P])O\<)J
ww,'n{_
HibernateException; Ns(F%zkm
@}:(t{>;e7
publicint getUserCount()throws HibernateException; .CYkb8hF
YR2/`9s\QJ
publicList getUserByPage(Page page)throws %3wK.tR
^gImb`<6-
HibernateException; Sb.;$Be5g
J%'|IwA
} t[Q\T0E
AsOI`@FV
~7g6o^A>
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`'`XB0vb
java代码: \&fK 8H1
R}FN6cH
X*@Sj;|m
/*Created on 2005-7-15*/ ; V8 =B8w
package com.adt.dao.impl; t*#T~3p
J5wq}<8
import java.util.List; Zh*I0m
w'C(? ?mH
import org.flyware.util.page.Page; NT0q!r/!
3;AAC (X
import net.sf.hibernate.HibernateException; -[z;y73]t
import net.sf.hibernate.Query; fy5)Tih%.*
4[D@[kAs
import com.adt.dao.UserDAO; ryPzq}#
p{U ro!J,K
/** XQ>m8K?\d
* @author Joa %"D-1&%zY
*/ K9c:K/H
public class UserDAOImpl extends BaseDAOHibernateImpl GmFNL/x8-v
h1$,
implements UserDAO { pB`<4+"9
,b{4GU$3
/* (non-Javadoc) udMq>s;
* @see com.adt.dao.UserDAO#getUserByName ~p&sd)
uP.3(n[&
(java.lang.String) qmhHHFjQ
*/ Em;zi.Y+V
publicList getUserByName(String name)throws .3#Tw'% G
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HibernateException { /OEj]DNY
String querySentence = "FROM user in class hz!.|U@,{<
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com.adt.po.User WHERE user.name=:name"; Q =Z-vTD+
Query query = getSession().createQuery 1QThAFN
=>9`qcNW_
(querySentence); :v#3;('7
query.setParameter("name", name); @C#lA2(I4
return query.list(); gwyz)CUkL
} R/=yS7@{)
zrcSPh
/* (non-Javadoc) 9"[#\TW9Vb
* @see com.adt.dao.UserDAO#getUserCount() hq|/XBd||
*/ ^VD14V3
publicint getUserCount()throws HibernateException { ;-59#S&?tB
int count = 0; 2]|+.9B
String querySentence = "SELECT count(*) FROM sNWj+T
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user in class com.adt.po.User"; yfj<P/aA+
Query query = getSession().createQuery u7K0m!
jW
#-{4F?DA]y
(querySentence); b$hQB090
count = ((Integer)query.iterate().next tlE+G@|^
!"Kg
b;A
()).intValue(); i -+B{H
return count; HQ"D>hsuU
} .M04n\
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/* (non-Javadoc) |X>:"?4t
* @see com.adt.dao.UserDAO#getUserByPage 5bk5EE`
278
6tZF,
(org.flyware.util.page.Page) SKGYmleR
*/ vq|W&
publicList getUserByPage(Page page)throws )l^w _;
rxO|k0x^C
HibernateException { C+_ NG
String querySentence = "FROM user in class _("{fJ,A
UhNeY{6
com.adt.po.User"; f -bVcWI
Query query = getSession().createQuery Xcb\N
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[7V{4(%
(querySentence); <S<(wFE@4
query.setFirstResult(page.getBeginIndex()) @#nB]qV:e
.setMaxResults(page.getEveryPage()); tcfUhSz,I
return query.list(); Y>r9"X|&H
} IYd)Vv3'j
k@^)>J^
} LbnR=B!
;L|%H/SH
13Q|p,^R
Lf3:' n
cJ&%XN
至此,一个完整的分页程序完成。前台的只需要调用 o@}Jd0D4
Wcbb3N$+
userManager.listUser(page)即可得到一个Page对象和结果集对象 P7Kp*He)
C]82Mt
的综合体,而传入的参数page对象则可以由前台传入,如果用 Jjv,
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9M<{@<]dm
webwork,甚至可以直接在配置文件中指定。 t68h$u
_&P![o)x
下面给出一个webwork调用示例: qm2
java代码: dF"Sz4DY#
5TqX;=B
~nw]q<7r
/*Created on 2005-6-17*/ 't]=ps
package com.adt.action.user; ,JX/`7y
ygh*oVHO
import java.util.List; +v/_R{ M
9 u{#S}c`
import org.apache.commons.logging.Log; ~!\n
import org.apache.commons.logging.LogFactory; |nIm$ p'
import org.flyware.util.page.Page; U\P ;,o
A~u-Iv(U
import com.adt.bo.Result; iphe0QE[#}
import com.adt.service.UserService; 4Y[tx]<
import com.opensymphony.xwork.Action; !h4L_D0
mJl|dk_c
/** |,|b~>
* @author Joa 3DbS\jja
*/ S
7RB`I5
publicclass ListUser implementsAction{ ,*Jm\u
GHfsq|*j,Z
privatestaticfinal Log logger = LogFactory.getLog UT%^!@u
7*`cWT_X
(ListUser.class); 5\lOZYHX
mJp)nF8r~
private UserService userService; <GT&q <4w
-:&qNY:Vp
private Page page; ;vnG
\^i/:
privateList users; C[gy{40}
CNQ>J`4
/* '7 SFa]tH
* (non-Javadoc) a~jM^b;VN
*
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* @see com.opensymphony.xwork.Action#execute() lOYzo
*/ 1*, f
publicString execute()throwsException{ '(4$h3-gv7
Result result = userService.listUser(page); A70x+mjy^T
page = result.getPage(); =y.? =`"
users = result.getContent(); %i:Sf
return SUCCESS; rjHL06qE
} r&U