Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 PDX^MYoN
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fL"-K
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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 lMp)T**
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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 $dci?7q
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分页支持类: Rs8`M8(4%
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java代码: npz*4\4
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package com.javaeye.common.util; E<'3?(D9hL
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import java.util.List; Tm[IOuhM'?
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publicclass PaginationSupport { c^UG}:Y
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publicfinalstaticint PAGESIZE = 30; 9<P1?Q
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privateint pageSize = PAGESIZE; k5=0L_xc
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privateList items; qbHb24I
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privateint totalCount; Gs.id^Sf
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privateint[] indexes = newint[0]; +D`IcR-x
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privateint startIndex = 0; c5<M=$
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public PaginationSupport(List items, int Am!$\T%2
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totalCount){ Tw`^
setPageSize(PAGESIZE); ~DhYiOSo
setTotalCount(totalCount); D+N{'d?+
setItems(items); 0~R0)Q,
setStartIndex(0); %z tCcgu*
} _*9eAeJ
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public PaginationSupport(List items, int tV@!jaj\
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totalCount, int startIndex){ 8"LvkN/v^
setPageSize(PAGESIZE); :u`
setTotalCount(totalCount); \$V~kgQ0
setItems(items); z(aei(U=
setStartIndex(startIndex); y0M^oLx
}
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public PaginationSupport(List items, int HzF
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totalCount, int pageSize, int startIndex){ dMQtW3stY
setPageSize(pageSize); uYhm
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setTotalCount(totalCount); {XC# -3O
setItems(items); SQ]&nDd
setStartIndex(startIndex); nxKV7d@R
} votv rZ=
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publicList getItems(){ cc*A/lD
return items; u8v;O}#
} Im+<oZ
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publicvoid setItems(List items){ fl!8 \4
this.items = items; g[0b>r7
} D1;H,
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publicint getPageSize(){ B5~S&HQ?B6
return pageSize; 0ym>Hbax)
} kTT!gZP$
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publicvoid setPageSize(int pageSize){ -[|R\'i
this.pageSize = pageSize; !0CC &8C`
} (q59cA w~X
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publicint getTotalCount(){ G ?jKm_`L
return totalCount; BRPvBs?Q,{
} oa? bOm
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publicvoid setTotalCount(int totalCount){ PB_+:S^8
if(totalCount > 0){ "9jt2@<
this.totalCount = totalCount; ARGtWW~:
int count = totalCount / 2#1"(m{
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pageSize; <E/4/
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if(totalCount % pageSize > 0) ySAkj-< /P
count++; tj$&89
indexes = newint[count]; 7iMBDkb7
for(int i = 0; i < count; i++){ v;m`d{(i2
indexes = pageSize * o81RD#>E)
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i; Bn:"qN~
} J<hqF4z
}else{ ZeM~13[
this.totalCount = 0; [d
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} Sggha~E2s
} T'_#Dwmj*
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publicint[] getIndexes(){ e.-+zkQ8EI
return indexes; cjK\(b3
} -': ;0
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publicvoid setIndexes(int[] indexes){ H4RqOI
this.indexes = indexes; qLC_p)
} &!i'Q;q
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publicint getStartIndex(){ pRR1k?
return startIndex; vge4&H3a&
} ^4MRG6G
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publicvoid setStartIndex(int startIndex){ -c%#Hd
if(totalCount <= 0) S
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this.startIndex = 0; mq#8[D
elseif(startIndex >= totalCount) Yr!@p Hy
this.startIndex = indexes <&w(%<;
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[indexes.length - 1]; oZ]^zzoEcg
elseif(startIndex < 0) v7-z<'?s~
this.startIndex = 0; $-^
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else{ LV}Z[\?
this.startIndex = indexes ohEIr2
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[startIndex / pageSize]; Dh+<|6mx
} z`]sWi F0
} QC\r|RXW
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publicint getNextIndex(){ M{GT$Q
int nextIndex = getStartIndex() +
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pageSize; C>NLZMT
if(nextIndex >= totalCount) F)8M9%g5m
return getStartIndex(); shkyN
else !)r1zSY"g
return nextIndex; pNFVa<D
} DhVO}g)2#
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publicint getPreviousIndex(){ aHR+4m~)
int previousIndex = getStartIndex() - y.>1r7
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pageSize; bU4l|i;j
if(previousIndex < 0) }1kZF{KD<[
return0; ;$.^
else D[p_uDIz
return previousIndex; -3GlpC22
} q2+`a;_S
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} sq rY<@%
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抽象业务类 V}aZ}m{J
java代码: *-eDUT|O
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/** Zjkg"
* Created on 2005-7-12 mXwDB)O{)
*/ r=gF&Og,?
package com.javaeye.common.business; <dWms`QcO
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import java.io.Serializable; )z\ 73|w
import java.util.List; 1j_
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import org.hibernate.Criteria; mufXM(
import org.hibernate.HibernateException; u>\u}c
import org.hibernate.Session; S*l=FRFI
import org.hibernate.criterion.DetachedCriteria; %#7 ]
import org.hibernate.criterion.Projections; `E2RW{$A
import Oa-(Xp,n#
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org.springframework.orm.hibernate3.HibernateCallback; \=2<<
iv
import bQgtZHO
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org.springframework.orm.hibernate3.support.HibernateDaoS GHRr+
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upport; 4+B&/}FDLo
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends O77^.B
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HibernateDaoSupport { (zml704dI)
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privateboolean cacheQueries = false; WRqpQEY
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privateString queryCacheRegion; m)ENj6A>yP
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publicvoid setCacheQueries(boolean Ake$M^Bz
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cacheQueries){ !NO)|N>
this.cacheQueries = cacheQueries; aZ'(ar:
} |hD)=sCj
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publicvoid setQueryCacheRegion(String P$v9
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queryCacheRegion){ LI9
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this.queryCacheRegion = @(CJT-Ak
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queryCacheRegion; m% %\k
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} VmON}bb[zz
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publicvoid save(finalObject entity){ GK&R,q5}
getHibernateTemplate().save(entity); R4%}IT^%P
} )mu[ye"p
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publicvoid persist(finalObject entity){ m\f}?t
getHibernateTemplate().save(entity); Ksf f]##H
} rqTsKrLe
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publicvoid update(finalObject entity){ @MxB
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getHibernateTemplate().update(entity); &PUn,9 Rm
} M*Ri1
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publicvoid delete(finalObject entity){ m't8\fo^w
getHibernateTemplate().delete(entity); rm%MQmF
} 534DAhpD=.
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publicObject load(finalClass entity, cD'|zH]
8,L)=3m-
finalSerializable id){ 4W<8u(
return getHibernateTemplate().load JIXZI\Fk
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(entity, id); %?PRBE'}'
} G O[u
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publicObject get(finalClass entity, RG6U~o1
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finalSerializable id){ #{g6'9PMz
return getHibernateTemplate().get YhO-ecN
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(entity, id); mJ'5!G
} RYV:?=D7s
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publicList findAll(finalClass entity){ _i2guhRs*Q
return getHibernateTemplate().find("from .zo>,*:t
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" + entity.getName()); _ykT(`.#
} do DpTwvh
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publicList findByNamedQuery(finalString Yu:!l>
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namedQuery){ !"SuE)WM
return getHibernateTemplate ]SL0Mn g8
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().findByNamedQuery(namedQuery); n{=N f|=
} >{eGSSG0
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publicList findByNamedQuery(finalString query, 78kT}kgW
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finalObject parameter){ #;hYJ Y
return getHibernateTemplate V5rW_X:]8
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().findByNamedQuery(query, parameter); S8Yti
} M,g$
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publicList findByNamedQuery(finalString query, k? !'OHmBL
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finalObject[] parameters){ lr9s`>9
return getHibernateTemplate >#|%y>g .o
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().findByNamedQuery(query, parameters); cm`x;[e6l
} F!cRx%R
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publicList find(finalString query){ :|N(:W>=$Y
return getHibernateTemplate().find W$`p ,$ .n
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(query); ]L_h3Xz\X
} oT*qMLdn
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publicList find(finalString query, finalObject c}mWAZ=wF
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parameter){ h[oI/X
return getHibernateTemplate().find VH6J
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(query, parameter); OFn#C!
} wqA7_
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public PaginationSupport findPageByCriteria ,rWej;CzN
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(final DetachedCriteria detachedCriteria){ 6.k>J{GG
return findPageByCriteria DwIX\9
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Iz9b5
} E&>=
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public PaginationSupport findPageByCriteria >=d%t6%(
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(final DetachedCriteria detachedCriteria, finalint M{ O8iq[
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startIndex){ aS&,$sR
return findPageByCriteria c. 06Sw*
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(detachedCriteria, PaginationSupport.PAGESIZE, .y>G/8_i
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startIndex); u9D#5NvGs
} &nfGRb
p>= b|Qy|
public PaginationSupport findPageByCriteria X*e<g=
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(final DetachedCriteria detachedCriteria, finalint e<r}{=1w
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pageSize, !EB[Lutm
finalint startIndex){ #9(L/)^
return(PaginationSupport) ev9ltl{
@<C<rB8R
getHibernateTemplate().execute(new HibernateCallback(){ p
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publicObject doInHibernate fm$)?E_Rp
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(Session session)throws HibernateException { rixt_}aE
Criteria criteria = aW(Hn[}^
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detachedCriteria.getExecutableCriteria(session); Rv)>xw
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount nP#|JRn=
rA[wC%%
()).uniqueResult()).intValue(); LW*v/`@
criteria.setProjection pvY BhTz0
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(null); Z&Xp9"j,@;
List items = WFG`-8_e[I
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criteria.setFirstResult(startIndex).setMaxResults _7b' i6-
k@>y<A{;D
(pageSize).list(); @w73U;9\
PaginationSupport ps = G1G*TSf
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new PaginationSupport(items, totalCount, pageSize, ~;yP{F8?
@3Gr2/a
startIndex); s_%KWkS
return ps; E@_]L<Z
} `]j:''K
}, true); 9}jezLI/3
} lB*HLC
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public List findAllByCriteria(final .dKFQH iYJ
@ ('/NjTZ
DetachedCriteria detachedCriteria){ CJe~>4BT
return(List) getHibernateTemplate 4^_'LiX3[
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().execute(new HibernateCallback(){ ^]X\boWlI
publicObject doInHibernate v`Yj)
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(Session session)throws HibernateException { {3eg4j.Z
Criteria criteria = fzZ`O{$8
D] +]Br8
detachedCriteria.getExecutableCriteria(session); {8T/;K@
return criteria.list(); Pd04
} jKr>Ig=$tA
}, true); Eal*){"<,?
} \^x`GsVy
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public int getCountByCriteria(final
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DetachedCriteria detachedCriteria){ bPVQ-
Integer count = (Integer) v /x~L$[
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getHibernateTemplate().execute(new HibernateCallback(){ PauF)p
publicObject doInHibernate |OBh:d_B]
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(Session session)throws HibernateException {
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Criteria criteria = \k.W
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detachedCriteria.getExecutableCriteria(session); r mJ`^6V
return NM+(ss'
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criteria.setProjection(Projections.rowCount 3gs!ojG
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()).uniqueResult(); q!AcMd\
} p mUG`8SY
}, true); vbEO pYCS
return count.intValue(); Zmz $
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} 7UsU03
} #j4RX:T*[
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用户在web层构造查询条件detachedCriteria,和可选的 ).IK[5Q`
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 C_;A~iI7
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PaginationSupport的实例ps。 /a}`
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ps.getItems()得到已分页好的结果集 B{!*OC{l
ps.getIndexes()得到分页索引的数组 W~j>&PK,?
ps.getTotalCount()得到总结果数 pvhN.z
ps.getStartIndex()当前分页索引 '$5Qdaj
ps.getNextIndex()下一页索引 `J%35
ps.getPreviousIndex()上一页索引 AmB*4p5b
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 / "@cv{
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 5xhYOwQBo
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一下代码重构了。 6"yIk4u:
Y2$xlqQd"
我把原本我的做法也提供出来供大家讨论吧: $S/EIN c
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首先,为了实现分页查询,我封装了一个Page类: 1F R
java代码: z@[-+Q:
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/*Created on 2005-4-14*/ xM?tdQ~VHY
package org.flyware.util.page; M8${&&[;
t8.^Y TI
/** Bdm05}c@u
* @author Joa ak\[+wQ
* rPK 1#
*/ <xUX&J=;
publicclass Page { ~p
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lBLL45%BIN
/** imply if the page has previous page */ y.gjs<y
privateboolean hasPrePage; 10CRgrZ
yH0vESgv
/** imply if the page has next page */ S]?I7_
privateboolean hasNextPage; gwDVWhq
jD?*sd
/** the number of every page */ YL/B7^fd8
privateint everyPage; Hb\['VhzM
b1EY6'R2
/** the total page number */ A`*Sx"~jdx
privateint totalPage; :@~mN7O*
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/** the number of current page */ 03gYl0B
privateint currentPage; *BKIA
A().1h1_k
/** the begin index of the records by the current Bz?
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query */ @PV3G
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privateint beginIndex; Mp06A.j[
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/** The default constructor */ x#fv<Cj4
public Page(){ ''}2JJU{
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} ,6aF~p;wI|
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/** construct the page by everyPage yC[Q-P *rG
* @param everyPage d
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* */ 9yp'-RKjw
public Page(int everyPage){ 4P?@NJp
this.everyPage = everyPage; I "HEXsSe
} /%TL{k&m$
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/** The whole constructor */ ]{18-=
public Page(boolean hasPrePage, boolean hasNextPage, x!fgZr{
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int everyPage, int totalPage, Zou;o9Ww
int currentPage, int beginIndex){ a~Yq0 d?`D
this.hasPrePage = hasPrePage; %v[KLMo'(
this.hasNextPage = hasNextPage; 9>=S@hVMd
this.everyPage = everyPage; @[bFlqsE
this.totalPage = totalPage; |}Z2YDwO/
this.currentPage = currentPage; 4jW <*jM
this.beginIndex = beginIndex; KgXu x-q
} .gY=<bG/fA
2:&L|;
/** j-wKm_M#jX
* @return rW+}3] !D/
* Returns the beginIndex. + aWcK6
*/ Li9>RY+3
publicint getBeginIndex(){ 8Fv4\dr
return beginIndex; gdS@NUM
} ($t;Xab
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/** ) .W0}
* @param beginIndex UL"
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* The beginIndex to set. !e}4>!L,(^
*/ o_&Qb^W
publicvoid setBeginIndex(int beginIndex){ |k]fY*z(
this.beginIndex = beginIndex; . dJBv
} 4jC7>mE
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/** D[`~=y(
* @return -fOBM 4
* Returns the currentPage. @ X5#?
*/ XV1XzG# C
publicint getCurrentPage(){ `Dp4Z>|
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return currentPage; f&
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} &U\//
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/** }O2P>Z?V
* @param currentPage p ^Y2A
* The currentPage to set. b1yS1i
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*/ PsBLAr\ah
publicvoid setCurrentPage(int currentPage){ u24XuSe$
this.currentPage = currentPage; -_bDbYL
} S7j U:CLJ
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/** ;f
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* @return )*&61
* Returns the everyPage. NG:
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*/ f/U~X;
publicint getEveryPage(){ (#+81 Dr
return everyPage; y w:=$e5
} ON"p^o>/_?
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/** i:H]Sb)<b
* @param everyPage x^McUfdr|
* The everyPage to set. ol}}c6
*/ *vT Abk$
publicvoid setEveryPage(int everyPage){ tv5N
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this.everyPage = everyPage; wpt5'|I
} )lP(isFP
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/** 7Ac.^rv5
* @return 60l!3o"p!
* Returns the hasNextPage. MHS|gR.c
*/ dRUmC H
publicboolean getHasNextPage(){ (O/W`qo
return hasNextPage; (/7cXd@\6
} YD#L@:&gv
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/** %yK- Q,'O
* @param hasNextPage \W|ymV_Ki
* The hasNextPage to set. \/9 O5`u*V
*/ t-Ble
publicvoid setHasNextPage(boolean hasNextPage){ t-SZBNb
this.hasNextPage = hasNextPage; AvB21~t&]
} .e\PCf9v
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/** ^G
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* @return 4@0Z<8Mo
* Returns the hasPrePage. }S{VR(i`J
*/ lYU?j|n
publicboolean getHasPrePage(){ df/7u}>9
return hasPrePage; zUWeOR'X
} SPnW8
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/** KBA&s
* @param hasPrePage Z>*a:|
* The hasPrePage to set. L%Ms?`i,
*/ sTvw@o*
publicvoid setHasPrePage(boolean hasPrePage){ Ct$\!|aR
this.hasPrePage = hasPrePage; D8`SI21P
} Nj +^;Y
DIgur}q)@
/** A(z
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* @return Returns the totalPage. QiaBZAol
* h]}DMVV]
*/ dwb ^z+
publicint getTotalPage(){ T*k}E
return totalPage; VRg
y
} 'fZ\uMdTx
hJ?PV@xy
/** XE#$|Z
* @param totalPage ycf)*0k
* The totalPage to set. 2B+qS'OT
*/ WUb] 8$n
publicvoid setTotalPage(int totalPage){ NKiWt
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this.totalPage = totalPage; _jaB[Q=By
} 8J~-|<Q6
'@1C$0tx
} sVe<l mL
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-}RGz_LO/
VdGpreRPC
[4+I1UR`
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 #Vy:6O
HT6$|j
个PageUtil,负责对Page对象进行构造: p9&gKIO_m
java代码: [@@EE>
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/*Created on 2005-4-14*/ BY@l:y4
package org.flyware.util.page; Yi <1z:\
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import org.apache.commons.logging.Log; zX6Q7Bc
import org.apache.commons.logging.LogFactory; Y4[oa?G
k h6n(B\
/** &,* ILz
* @author Joa 1JV-X G6
* ssl.Y!
*/ :.(A,
publicclass PageUtil { |3>%(4
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privatestaticfinal Log logger = LogFactory.getLog 7@&kPh}PG
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(PageUtil.class); V?~!D p
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/** (IIZ vCek
* Use the origin page to create a new page &g]s@S|%
* @param page HE0m#
* @param totalRecords 8EU/}Ym
* @return ,x?Jrcx~'C
*/ < Yc)F.:
publicstatic Page createPage(Page page, int %zO>]f&
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totalRecords){ YUTI)&y
return createPage(page.getEveryPage(), +K,T^<F;
7tne/Yz
page.getCurrentPage(), totalRecords); m=a^t
} a'O-0]g,
JW"n#sR4
/** w8zr0z
* the basic page utils not including exception }|wC7*^)
*d31fBCk%
handler >u]9(o7I
* @param everyPage ((M>To_l
* @param currentPage fh`}~ aQ
* @param totalRecords ^-F#"i|Cn
* @return page h;R>|2A
*/ G[n;%c~`+
publicstatic Page createPage(int everyPage, int )_}xK={
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currentPage, int totalRecords){ FytGg[#]
everyPage = getEveryPage(everyPage); SAE'y2B*
currentPage = getCurrentPage(currentPage); z'\BZ5riX<
int beginIndex = getBeginIndex(everyPage, l
nJ
]l`V#Rd
currentPage); >O0<u
int totalPage = getTotalPage(everyPage, ,[3}t%Da
<YrsS-9
totalRecords); bm h@SB
boolean hasNextPage = hasNextPage(currentPage, G/_xn5XDD
ux)Wh.5
totalPage); +W8kMuM!
boolean hasPrePage = hasPrePage(currentPage); Hm+VGH'H?
2'Raj'2S4
returnnew Page(hasPrePage, hasNextPage, hsJGly5H
everyPage, totalPage, )~IOsTjI
currentPage, 2nCHL'8N
R7c42L\QA
beginIndex); #}Bv/`t
} ;@O8y\@
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tN
privatestaticint getEveryPage(int everyPage){ r4 qs!(
return everyPage == 0 ? 10 : everyPage; Z_>:p^id
} /l8wb~vl
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privatestaticint getCurrentPage(int currentPage){ 7^1K4%IPl
return currentPage == 0 ? 1 : currentPage; t0Inf
[um
} |nU%H=Rs/
t{`uN
privatestaticint getBeginIndex(int everyPage, int #TcX5
yZb})4.
currentPage){ r]Lj@0F>8
return(currentPage - 1) * everyPage; Oq(FV[N7t
} cQ3p|a `
B_C."{G
privatestaticint getTotalPage(int everyPage, int }N:QB}7'_
y,`q6(&
totalRecords){ ygd*zy9
int totalPage = 0; O9RnS\
ry+|gCZ
if(totalRecords % everyPage == 0) %}unlSTPP
totalPage = totalRecords / everyPage; }H/94]~tH
else e0IGx]5i
totalPage = totalRecords / everyPage + 1 ; QBA{*@ A-
'-#gQxIpD
return totalPage; *z]P|_:&G
} @6-3D/=
S_s;foT
privatestaticboolean hasPrePage(int currentPage){ L!fIAd`
return currentPage == 1 ? false : true; s !II}'Je
} s"~,Zzy@j
F*Ul#yX
privatestaticboolean hasNextPage(int currentPage, D'Uc?2X,&
SCjVzvG$yg
int totalPage){ 2o7o~r
return currentPage == totalPage || totalPage == BF"eVKA
%Rf{v5
0 ? false : true; 4-9cp=\PE
} "&\(:#L
\*pS4vy5x
ClufP6'
} ^c"\%!w"O
Psm9hP :m
|T-Ytuy8
}S%}%1pG7
ES#q/yab5
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。 r MJ4w['J=
24fN3
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 9e&*++vf
z_). -
做法如下: 5Gz~,_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a;(,$q3M
^}kYJvqA
的信息,和一个结果集List:
-:wV3D
java代码: -*2b/=$u
3Qp6$m
c~6ywuq+M`
/*Created on 2005-6-13*/ {@s6ly].
package com.adt.bo; bHzZ4i
"AIS6%,
import java.util.List; L>N)[;|
$GVf;M2*
import org.flyware.util.page.Page;
@;[. #hK
\P*%u
/** 7e{w,.ny!
* @author Joa 2(GLc*B>
*/ =wa5\p/
publicclass Result { e)i-$0L"
K%SfTA1TCB
private Page page; p4K
8L'nZ
}@53*h i(
private List content; |+=ctpx9&
o
Y<vKs^
/** clr]gib
* The default constructor zj=F4]w
*/ 'NnmLM(oh
public Result(){ T n,Ifo3
super(); 2XeN E[
} PG'I7)Bv
2 xi@5;!
/** W#^p%?8pR
* The constructor using fields ?MiMwVR
* " j:15m5
* @param page _$v$v$74^
* @param content ^AO2%09.S
*/ xCMuq9zt@
public Result(Page page, List content){ C+gu'hD
this.page = page; 1i Q(q\%
this.content = content; w aDJ
} |8\et
Q}#H|@
/** >~&7D`O
* @return Returns the content. Bv`3T Af2
*/ 24Htr/lPCT
publicList getContent(){ 1EHNg<J(
return content;
w Qp{z
} UZE%!OWpeK
p+{*w7?8"[
/** @T sdgx8
* @return Returns the page. tgu
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*/ `y.i(~^1
public Page getPage(){ ML
X: S?
return page; BFn}~\wzK
} L/O:V^1
1:"ZS ]i
/**
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* @param content lpefOnO[
* The content to set. D&8*4>
*/ >Wj8[9zf
public void setContent(List content){ 2K2jko9'a
this.content = content; l"
H/PB<.
} P"c7h7
JI92Dc*o
/** McU]U9:z
* @param page 8V:yOq10
* The page to set. 0y#TGM|0D
*/ `Y7&}/OM
publicvoid setPage(Page page){ +]{PEnJ
this.page = page; Rs 0Gqx
} r$Y% 15JV
} Umk ! m] q
jyjK~!0
h,'m*@Eg
}sGH}n<9*
i(<do "Am<
2. 编写业务逻辑接口,并实现它(UserManager, 8f#&CC!L
6z+*H7Qz
UserManagerImpl) No)@#^
java代码: f@IL2DL}\
GSg/I.)S
N~M-|^L
/*Created on 2005-7-15*/ L|w}#|-
package com.adt.service; qd?k#Gw&
%5?0+~
import net.sf.hibernate.HibernateException; h&?tF~h
SyR[G*djl
import org.flyware.util.page.Page; $RV'DQO
-ID!kZx
import com.adt.bo.Result; n15lX,FI
C`C$i>X7^
/** ]i:O+t/U
* @author Joa C)Hb=
*/ 3?DM
AV
publicinterface UserManager { -o0~xspF
{-\VX2:;[9
public Result listUser(Page page)throws 2<5s0GT'/
NU|T`gP
HibernateException; YQ<O.E
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} 9#niMv9
}!RFX)T
,LJX
_p=O*$b.
K)t+lJ
java代码: }))JzrqAe
To19=,:
m/W)IG>
/*Created on 2005-7-15*/ %y;Cgo[
package com.adt.service.impl; lO0 PZnW9
Z"G@I= Q(
import java.util.List; KA$l.6&d
NFcMh+qnK
import net.sf.hibernate.HibernateException;
zWI C4:
l]o&D))R
import org.flyware.util.page.Page; }x1p~N+;
import org.flyware.util.page.PageUtil; "5R8Zl+
%8yX6`lH
import com.adt.bo.Result; O
hcPlr
import com.adt.dao.UserDAO; geu8$^
import com.adt.exception.ObjectNotFoundException; z,B'I.)M
import com.adt.service.UserManager; !B{N:?r
CEos`
/** D+vHl}
* @author Joa E`SFr
*/ `$D2w|
publicclass UserManagerImpl implements UserManager { X6]eQ PN2
gyW##M@{
private UserDAO userDAO; n/5)}( }K
HLcK d`$/
/** &Q"Ox{~W
* @param userDAO The userDAO to set. '\X<+Sm'
*/ ef=LPCi?
publicvoid setUserDAO(UserDAO userDAO){ !&D&Gs
this.userDAO = userDAO; wA<#E6^vG
} niV= Ijt{5
fu 95-)M
/* (non-Javadoc) 0@ 9em~
* @see com.adt.service.UserManager#listUser 64OgE!
Vee`q.
(org.flyware.util.page.Page)
D=nuK25
*/ 'WG%O7s.
public Result listUser(Page page)throws 4X2/n
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HibernateException, ObjectNotFoundException { 2*K _RMr~
int totalRecords = userDAO.getUserCount(); =@>[
if(totalRecords == 0) XZe ZqBr
throw new ObjectNotFoundException Td5;bg6Qy
VL/%D*
("userNotExist"); fK|F`F2V
page = PageUtil.createPage(page, totalRecords); *gC6yQ2?
List users = userDAO.getUserByPage(page); fN TPW]
returnnew Result(page, users); I2=?H<
} r9@Q="J_)
GJY7vS^#
} ?B2 T'}~
^\uj&K6l
<tbsQ3
*@r)3
5h^U ]Y#
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fr%}|7
Z\d7dbv
询,接下来编写UserDAO的代码: MhZT<6
3. UserDAO 和 UserDAOImpl: Ncu\;K\N
java代码: 0 ej!!WP
Fss7xP'
u"\HBbBx
/*Created on 2005-7-15*/ ;w,g|=RQ
package com.adt.dao; f`?Y+nu}
]kuMzTH
import java.util.List; P2h}3%cJq
o5\nqw^
import org.flyware.util.page.Page; $gN1&K
>g@;`l.Z#
import net.sf.hibernate.HibernateException; \*s'S*~
*1}'ZEaJ
/** 3Q`F x
* @author Joa 40}8EP k)
*/ Brh<6Btl
publicinterface UserDAO extends BaseDAO { V Z[[zYe
uJ4RjLM`
publicList getUserByName(String name)throws $g55wG F
n;0bVVMV
HibernateException; 3n/U4fn_
2!/_Xh
publicint getUserCount()throws HibernateException; ; 9pOtr
~B%=g)w
publicList getUserByPage(Page page)throws VrA9}"1x~*
= !'gV:M
HibernateException; YB h:
8]Xwj].^C
} G l=dL<F
`7P4O
-<jb>8
qh/q<
*K6 V$_{S
java代码:
f$mfY6v
%Lexu)odW
50oNN+;=R
/*Created on 2005-7-15*/ UDHk@M
package com.adt.dao.impl; |*0oz=
5rqjqfFa
import java.util.List; yG5T;O&
"PBUyh-Z
import org.flyware.util.page.Page; mfO:#]K
zm}4=Kz}
import net.sf.hibernate.HibernateException; N0h"EV[
import net.sf.hibernate.Query; q#-szZQ
\.A~>=:
import com.adt.dao.UserDAO; MEbx{XC
W
xyQA:3s
/** ?w1_.m|8u
* @author Joa m&DDz+g
*/ :<w3.(Z
public class UserDAOImpl extends BaseDAOHibernateImpl 6>)]7(B<d
Rx*T7*xg{
implements UserDAO { L=Q-r[
z]> 0A
/* (non-Javadoc) ,ijgq EN
* @see com.adt.dao.UserDAO#getUserByName W$@q
~/E
1sZwW P
(java.lang.String) Xi_>hL+R(
*/ :cop0;X:Wm
publicList getUserByName(String name)throws pJx88LfR
\BaN?u)a
HibernateException { '|<