Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 \c\~k0u
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 KS*,'hvY
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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 Fip
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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 1m5l((d
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。 O>DS%6/G
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分页支持类: Hhtl~2t!0
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java代码: Q"I(3 tp9[
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package com.javaeye.common.util; h\!8*e;RAW
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import java.util.List; 6/<Hx@r (
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publicclass PaginationSupport { f&CQn.K"
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publicfinalstaticint PAGESIZE = 30; # `^nmC/F
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privateint pageSize = PAGESIZE; g|Lbe4?
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privateList items; 6>]
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privateint totalCount; O84:ejro
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privateint[] indexes = newint[0]; aV$kxzEc
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privateint startIndex = 0; rN9qH
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public PaginationSupport(List items, int !L.R"8!
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totalCount){ vb[0H{TT2
setPageSize(PAGESIZE); '9!_:3[d\]
setTotalCount(totalCount); 0J+WCm`
setItems(items); S${%T$>
setStartIndex(0); :fj>JF\[
} vD8pVR+
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public PaginationSupport(List items, int Movm1*&=
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totalCount, int startIndex){ t{c:<nN
setPageSize(PAGESIZE); *+*W# de.
setTotalCount(totalCount); ND1hZ3(^
setItems(items); x\'3UKQP+^
setStartIndex(startIndex); g?80>-!bF
} S*<J y(:n
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public PaginationSupport(List items, int ,marNG
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totalCount, int pageSize, int startIndex){ ry|a_3X(I
setPageSize(pageSize); XMS:F]HN
setTotalCount(totalCount); no8\Oees
setItems(items); d 0B`5#4
setStartIndex(startIndex); bit|L7*14
} R[zN?
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publicList getItems(){ Ug+ K:YUq
return items; [\3ZMH
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} c@g(_%_|2
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publicvoid setItems(List items){ !:xycLdfUp
this.items = items; i!%WEHPe
} w)ki<Dudg
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publicint getPageSize(){ Q~(Qh_Ff
return pageSize; 7C'@g)@^/
} w=]A;GgA
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publicvoid setPageSize(int pageSize){ ?;o0~][!
this.pageSize = pageSize; [;{xiW4V]
} I=dn]}b#P
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publicint getTotalCount(){ 0UJ6>Rj
return totalCount; yf&_l^!
} >>$L
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publicvoid setTotalCount(int totalCount){ %T$>E7]!
if(totalCount > 0){ Je|:\Qk
this.totalCount = totalCount; ?GH/W#{o)
int count = totalCount / x%s1)\^A
v)np.j0V7
pageSize; E
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if(totalCount % pageSize > 0) &OJ?Za@p@)
count++; MhA4C 8
indexes = newint[count]; vLxaZWr
for(int i = 0; i < count; i++){ 5/Qu5/
indexes = pageSize * "Bwz
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i; c3GBY@m
} \)5mO 8w
}else{ <pV8
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this.totalCount = 0; <.Zh{"$qo
} OK v2..8
} J-/w{T8:
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publicint[] getIndexes(){ +%j27~R>D
return indexes; Ej)7[
} L{VnsY V
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publicvoid setIndexes(int[] indexes){ c$,1j%[)
this.indexes = indexes; p@O Ip
} -HGRrWS
4
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publicint getStartIndex(){ QOK,-
return startIndex; c
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} E[#VWM
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publicvoid setStartIndex(int startIndex){ OD7^*j(p`
if(totalCount <= 0) x %`YV):*
this.startIndex = 0; Wu*
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elseif(startIndex >= totalCount) va_u4
this.startIndex = indexes x-c5iahp'
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[indexes.length - 1]; E`.hM}h
elseif(startIndex < 0) bvJ@H
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this.startIndex = 0; Xg]Cq"RJC
else{ Rd7U5MBEF
this.startIndex = indexes lx4pTw1
q#AIN`H
[startIndex / pageSize]; 9]Ue%%vM
} S'^ q
} ;o'r@4^&$R
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publicint getNextIndex(){ (/nnN4\=
int nextIndex = getStartIndex() + ,\iXZ5"R
59{X;
pageSize; 7b08Lo7b
if(nextIndex >= totalCount) ZHjL8Iq
return getStartIndex(); p?#T^{Quz~
else ECA<%'$?E
return nextIndex; cH*")oD
} 5qH*"i+|s
V*PL_|Q5
publicint getPreviousIndex(){ q
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int previousIndex = getStartIndex() - CR23$<FC
@Ol(:{<
pageSize; t O.5
if(previousIndex < 0) Ph]b6
return0; NA2={RB;
else qJT/48lf_
return previousIndex; fQC{LcS
} awo'#Y2>
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} , @UOj=
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抽象业务类 8#JX#<HEo
java代码: TW>GYGz
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/** JDR_k
* Created on 2005-7-12 deaB_cjdI
*/ 6d/Q"As
package com.javaeye.common.business; VQqBo~
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import java.io.Serializable; Dfzj/spFV
import java.util.List; J)n_u) ,
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import org.hibernate.Criteria; UJh;Hp:
import org.hibernate.HibernateException; 1xEOYM)
import org.hibernate.Session; _b%)
import org.hibernate.criterion.DetachedCriteria; W;=Ae~
import org.hibernate.criterion.Projections; /;(ji?wN
import Ur]$@N
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org.springframework.orm.hibernate3.HibernateCallback; FHU6o910
import 'I/_vqp@
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org.springframework.orm.hibernate3.support.HibernateDaoS ";=!PL
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upport; _rB,N#{2R=
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import com.javaeye.common.util.PaginationSupport; CnL=s6XD'
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public abstract class AbstractManager extends MuOKauYa
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HibernateDaoSupport { }~+,x#
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privateboolean cacheQueries = false; T 'c39
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privateString queryCacheRegion; =[]6NjKS,
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publicvoid setCacheQueries(boolean 3E*m.jX
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cacheQueries){ E>]K#H
this.cacheQueries = cacheQueries; ]Ac}+?
} l~;>KjZg
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publicvoid setQueryCacheRegion(String ]87BP%G
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queryCacheRegion){ Dj96t5R
this.queryCacheRegion = ) %Fwfb
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queryCacheRegion; ?< b{
} J?3/L&seA
.+ u
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publicvoid save(finalObject entity){ 7?R600OA
getHibernateTemplate().save(entity); dWQsC|
} GKo&?Tj)
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publicvoid persist(finalObject entity){ -&Xv,:'?
getHibernateTemplate().save(entity); IyHbl_P ^
} *p
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publicvoid update(finalObject entity){ BJUj#s0$
getHibernateTemplate().update(entity); $!>.h*np
} P!|Z%H
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publicvoid delete(finalObject entity){ &$/
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getHibernateTemplate().delete(entity); d)vP9vXy
} oV:oc,
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publicObject load(finalClass entity, XJe=+_K9
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finalSerializable id){ eo9/
return getHibernateTemplate().load ~I5hV}ZT
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(entity, id); RN(I}]] a
} &kIeW;X
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publicObject get(finalClass entity, @Iz]:@\cJ
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finalSerializable id){ j-ej7
return getHibernateTemplate().get V,_m>$Mo
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(entity, id); pjFO0h_Y
} vv
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publicList findAll(finalClass entity){ +>q#eUS)
return getHibernateTemplate().find("from :_R:>n9 p
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" + entity.getName()); 2DCQ5XewYe
} PoF3fy%.
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publicList findByNamedQuery(finalString N;|^C{uz
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namedQuery){ } jj)
return getHibernateTemplate hX{,P:d=f
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().findByNamedQuery(namedQuery); \2s`mCY
} [Iks8ZWr_
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publicList findByNamedQuery(finalString query, *XTd9E^tXq
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finalObject parameter){ |EE1S{!24m
return getHibernateTemplate 6^Wep- $
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().findByNamedQuery(query, parameter); GF ux?8A:%
} |HK:\)L%
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publicList findByNamedQuery(finalString query, >Wr%usNxc
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finalObject[] parameters){ O{LCHtN
return getHibernateTemplate K29/7A/
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().findByNamedQuery(query, parameters); {]^Ixm-,f
} ?mg@z q8
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publicList find(finalString query){ &-ropY
return getHibernateTemplate().find -@#w)
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(query); p
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} F^O83[S
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publicList find(finalString query, finalObject !&VfOx:PN
8?+|4:#=*J
parameter){ .Fn|Okn^gr
return getHibernateTemplate().find hk~/W}sI
W" 5nS =d%
(query, parameter); ]b4IO4T
} $,4h\>1WP
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public PaginationSupport findPageByCriteria NHGTV$T`1
\]9)%3I
(final DetachedCriteria detachedCriteria){ q\0/6tl_
return findPageByCriteria sAkr-x?+M
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @ma(py
} \Rny*px
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public PaginationSupport findPageByCriteria dVQ[@u1,
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(final DetachedCriteria detachedCriteria, finalint e,U:H~+]
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startIndex){ BR2Gb~#T
return findPageByCriteria
po*G`b;v
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(detachedCriteria, PaginationSupport.PAGESIZE, kU<t~+
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startIndex); c2npma]DZ
} z:,PwLU
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public PaginationSupport findPageByCriteria C ^Y\?2h1
8-2`S*
(final DetachedCriteria detachedCriteria, finalint 4_R|3L
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pageSize, x|6]+?l@6
finalint startIndex){ -R`{]7V
return(PaginationSupport) YFO{i-*q
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getHibernateTemplate().execute(new HibernateCallback(){ g$nS6w|5H
publicObject doInHibernate 5'lPXKn+L
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(Session session)throws HibernateException { B
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Criteria criteria = @]@|H?
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detachedCriteria.getExecutableCriteria(session); z5>I9R^q;
int totalCount = H71sxek3
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((Integer) criteria.setProjection(Projections.rowCount HK@ij,px
.Bm%
()).uniqueResult()).intValue(); [xMa^A>p
criteria.setProjection <)VgGjZ-H
";K w?
(null); +hxG!o?O
List items = ZitM<Qi&y
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criteria.setFirstResult(startIndex).setMaxResults X]0>0=^
<L&EH@T
(pageSize).list(); *DL7p8
PaginationSupport ps = ScPVjqG2{
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new PaginationSupport(items, totalCount, pageSize, AJPvwu}D
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startIndex); m#7(<#
return ps; 5~*)3z^V
} pCIzpEsRs
}, true); %$!3Pbui
} COrk (V
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public List findAllByCriteria(final Jz@~$L
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DetachedCriteria detachedCriteria){ !|cg=
return(List) getHibernateTemplate GtA`0B
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().execute(new HibernateCallback(){ +EETo):
publicObject doInHibernate FcDS*ZEk!
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(Session session)throws HibernateException { zKJ2~=
Criteria criteria = .|UQ)J?s
{Cx5m
detachedCriteria.getExecutableCriteria(session); ,^(]zZh
return criteria.list(); @AsJnf$y
} +a1x;
}, true); Cm}2 >eH
} OmYVJt_
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public int getCountByCriteria(final W'lqNOX[v
* QgKo$IF
DetachedCriteria detachedCriteria){ yK~=6^M
Integer count = (Integer) iGN\ >m}
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getHibernateTemplate().execute(new HibernateCallback(){ cnv>&6a)
publicObject doInHibernate ZO0 Ee1/
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(Session session)throws HibernateException { \o9 \ikR
Criteria criteria = JAPr[O&
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detachedCriteria.getExecutableCriteria(session); L4#pMc
return *H>rvE.K?
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criteria.setProjection(Projections.rowCount !rvEo =^
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()).uniqueResult(); uV/5f#)
} JxAQ,oOO
}, true); qWt}8_"
return count.intValue(); -yYdj1y;
}
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} `8:0x?X
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用户在web层构造查询条件detachedCriteria,和可选的 ;JW_4;-
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 NFK`,
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PaginationSupport的实例ps。 APQq F/
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ps.getItems()得到已分页好的结果集 G#M)5'Q]U
ps.getIndexes()得到分页索引的数组 x&}]8S)
ps.getTotalCount()得到总结果数 *GP2>oEM
ps.getStartIndex()当前分页索引 jG5HW*>k0
ps.getNextIndex()下一页索引 nB[-KS
ps.getPreviousIndex()上一页索引 ~(5r+Z}*`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ZzT=m*tQ&
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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 !xM5
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一下代码重构了。 eRauyL"Q+
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我把原本我的做法也提供出来供大家讨论吧: <=uYfi 3,
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首先,为了实现分页查询,我封装了一个Page类: S}m_XR]
java代码: V7ph^^sC}
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/*Created on 2005-4-14*/ [3%mNNk
package org.flyware.util.page; M>Q]{/V7T
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/** x 3@-E
* @author Joa oFY!NMq}:
* ON ?Y
Df
*/ D$>_W ,*V
publicclass Page { ,pNx(a
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/** imply if the page has previous page */ X1L@
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privateboolean hasPrePage; K%^n.
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/** imply if the page has next page */ jm_-f
privateboolean hasNextPage; )P$(]{
3} A$+PX
/** the number of every page */ /
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privateint everyPage; w =^.ICyb@
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/** the total page number */ 9KSi-2?H
privateint totalPage; _IH" SVub
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/** the number of current page */ GK?ual1
privateint currentPage; HpwMm^
V\V
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/** the begin index of the records by the current >r.]a `
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query */ 8h)XULs2
privateint beginIndex; 2*Z2uV^
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/** The default constructor */ ,d
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public Page(){ ``o]i{x
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} pwUXM?$R
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/** construct the page by everyPage ^aFm6HS1
* @param everyPage 5&Oc`5QD
* */
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public Page(int everyPage){ Hl*vS
this.everyPage = everyPage; Cu"Cpt[
} .UyE|t4
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/** The whole constructor */ J3$>~?^1
public Page(boolean hasPrePage, boolean hasNextPage, tDByOml8Ix
-[>de!
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int everyPage, int totalPage, A~ya{^}
int currentPage, int beginIndex){ \1EuHQ?
this.hasPrePage = hasPrePage; b*|~F
this.hasNextPage = hasNextPage; =Q#I@SVp2$
this.everyPage = everyPage; ^:nc'C gP
this.totalPage = totalPage; Ts iJK
this.currentPage = currentPage; D0.
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this.beginIndex = beginIndex; %E?Srs}j
} Vns3859$8
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/** HDVimoOq
* @return bMH~vR
* Returns the beginIndex. y@P%t9l
*/ De $AJl
publicint getBeginIndex(){ "W<Y1$Y=Y
return beginIndex; b0P3S!E
} '3.\+^3
$:ush"=f8^
/** nD
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* @param beginIndex Daf|.5>(@
* The beginIndex to set. :uL<UD,vu3
*/ ;m/e|_4;y
publicvoid setBeginIndex(int beginIndex){ nF3}wCe)
this.beginIndex = beginIndex; &|>@K#V8-;
} &(F
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HR>Y?B{
/** p8Vqy-:
* @return fHt \KP
* Returns the currentPage. 'K[ml ?_
*/ oqrx7+0{
publicint getCurrentPage(){ V^~RDOSy7n
return currentPage; g?j)p y
} FaHOutP
=~^b
/** =?sG~
* @param currentPage "~KDm(D
* The currentPage to set. PN*
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*/ )ycI.[C
publicvoid setCurrentPage(int currentPage){ ;$p !dI\-Q
this.currentPage = currentPage; IUMv{2C
} Pk?$\
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/** ]HKt7 %,
* @return jP@ @<dt
* Returns the everyPage. {QG.> lB
*/ CTMC78=9}
publicint getEveryPage(){ Nc[@QC{
return everyPage;
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} wO??"${OH
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/** Ds1h18
* @param everyPage *PmZqe
* The everyPage to set. fRp]
*/ \"P{8<h.3
publicvoid setEveryPage(int everyPage){ [6GYYu\
this.everyPage = everyPage; >hunV'vu'
} +Z`=iia>
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/** r. 82RoG?G
* @return E@}F^0c
* Returns the hasNextPage. ?Uql30A
*/ l4C{LZ
publicboolean getHasNextPage(){ _!xrBdaJ
return hasNextPage; IZVP-
} Z|$#
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/** O&!R7T
* @param hasNextPage &raqrY|V
* The hasNextPage to set. 3%vXB=>T!
*/ T(|'.&a
publicvoid setHasNextPage(boolean hasNextPage){ I~,.@{4
this.hasNextPage = hasNextPage; RpdUR*K9x
} !'f7;%7s
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/** Pnytox
* @return ^eW<-n@^
* Returns the hasPrePage. BabaKSm}LP
*/ )&6gju7(
publicboolean getHasPrePage(){ Y6{^cZ!=
return hasPrePage;
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} 8/e-?2l
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/** <G})$f'x2
* @param hasPrePage wAh]C;+{
* The hasPrePage to set.
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*/ 3Z*r#d$nh:
publicvoid setHasPrePage(boolean hasPrePage){ fA=Z):w
this.hasPrePage = hasPrePage; 9QQ XB-
} 0`/G(ukO
,dC.|P' `
/** x $uhkP
* @return Returns the totalPage. 7# AIX],
* d$IROZK-D
*/ H'AN osv
publicint getTotalPage(){ Ft5A(P >
return totalPage; *%xbn8
} *)m:u :
5c- P lm%
/** Dka,v
* @param totalPage ?N kKDvv
* The totalPage to set. ^'3c%&Zf3
*/ jY6GWsh:9
publicvoid setTotalPage(int totalPage){ %QP[/5vQ
this.totalPage = totalPage; *_D/_Rp7
} N{J
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} 0O3O^
0
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2w|5SK_
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qu B[S)2}
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 5 -i,Tx&:
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个PageUtil,负责对Page对象进行构造: ~J\qkQ
java代码: _8G
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/*Created on 2005-4-14*/ {Y~>&B5
package org.flyware.util.page; }`=7%b`-?
e=;A3S
import org.apache.commons.logging.Log; CR4O#f8\
import org.apache.commons.logging.LogFactory; Av x`
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/** Jn+ -G4h$
* @author Joa ?Q:SVxzUd
* w=KfkdAJ*/
*/ "ESc^28
publicclass PageUtil { )KZMRAT-
PUQ",;&y1
privatestaticfinal Log logger = LogFactory.getLog yD"]:ts3
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(PageUtil.class); ]_C"A
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/** t/ \S9
* Use the origin page to create a new page WI\a
* @param page @$
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* @param totalRecords @=kgK[t
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* @return ky2]%cw
*/ ?:r?K|Ku
publicstatic Page createPage(Page page, int =lAjQt
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totalRecords){ =g+}4P
return createPage(page.getEveryPage(), LR=Ji7
E{
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b)
page.getCurrentPage(), totalRecords); IuY9Q8
} vyZ&%?{*R
dN5{W0_
/** 8N&'n
* the basic page utils not including exception oAO{4xP
XG|N$~N+ 2
handler }
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* @param everyPage Kx9u|fp5
* @param currentPage E2DfG^sGV
* @param totalRecords YR'F]FI
* @return page l'I:0a
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*/ )<5k+O~
publicstatic Page createPage(int everyPage, int (dlp5:lQz
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currentPage, int totalRecords){ J~%43!X\K
everyPage = getEveryPage(everyPage); m%0-3c(
currentPage = getCurrentPage(currentPage); '0Cp
int beginIndex = getBeginIndex(everyPage, GDSV:]hL
}=X: F1S
currentPage); o`f^ m
int totalPage = getTotalPage(everyPage, 3(e_2v
((ebSu2-?$
totalRecords); tV!?Ol
boolean hasNextPage = hasNextPage(currentPage, xn*$Ty+
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totalPage); -nSf<
boolean hasPrePage = hasPrePage(currentPage); z&;8pZr
exq5Z c%
returnnew Page(hasPrePage, hasNextPage, mx^Ga=:
?
everyPage, totalPage, \3hA_{ w
currentPage, T'p L&@,Q
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beginIndex); )Qb,zS6
} i~h@}0WR"
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privatestaticint getEveryPage(int everyPage){ y#'hOSR2
return everyPage == 0 ? 10 : everyPage; )$] lf }
} 4r(0+SO
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ng
privatestaticint getCurrentPage(int currentPage){ \Th<7WbR6#
return currentPage == 0 ? 1 : currentPage; y,5qY}P+
} wPg/.N9H
/\%<VBx ?q
privatestaticint getBeginIndex(int everyPage, int rZ?:$],U!
JpS}X\]i
currentPage){ 7^><Vh"qV
return(currentPage - 1) * everyPage; 6]v}
} %:aXEjm@
3}nk9S:jr
privatestaticint getTotalPage(int everyPage, int Oc L7] b0
e|Ri
totalRecords){ ;M?)-dpZ
int totalPage = 0; ]FCP|Jz
rpKZ>S|7+)
if(totalRecords % everyPage == 0) nJe}U#
totalPage = totalRecords / everyPage; n^nE&'[?0g
else AJ7w_'u=@
totalPage = totalRecords / everyPage + 1 ; %)j&/QdzF&
v@$N,g
return totalPage; 9JFN8Gf*)
} m?kiGC&m
AM-bs^
privatestaticboolean hasPrePage(int currentPage){ uG\~Hxqw7O
return currentPage == 1 ? false : true; *I 1 H
} X%b1KG|#(
%mC@}
privatestaticboolean hasNextPage(int currentPage, irQ'Rm[
L('1NN2
int totalPage){ $e+sqgU
return currentPage == totalPage || totalPage == AERJ]$\
poBeEpbs
0 ? false : true; iTHwH{!
} x)C}
j*>J1M3E
[1rQ'FBB^1
} =muQ7l:(
"'CvB0>
|<Ls;:5.
\\SQACN
1gHe$dzXk
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 c~hH
7/v
M|blg!j;
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 |O(>{GH
t9`{^<LH
做法如下: /1EAj
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 v +4v
2W+~{3[#
的信息,和一个结果集List: vzSb(
java代码: DvH-M3
W_B=}lP@x
jZ.yt+9
/*Created on 2005-6-13*/ _ ^FC9
package com.adt.bo; SWrTM
W'4/cO
import java.util.List; ?("O.<
^$ Y9.IH"
import org.flyware.util.page.Page; [-\ Y?3
]r;rAOWVV
/** :^y!z1\2(7
* @author Joa lgews"
*/ WX4sTxJK
publicclass Result { kgo#JY-4
>SXSrXyYX
private Page page; k>ErDv8
b/_Zw^DPC
private List content; Hf('BagBL
SRfh{u
/** m]?Z_*1
* The default constructor =RWTjTZ
*/ W^iK9|[qp
public Result(){ &%fcGNzJQ
super(); CA#g(SiZ
} ^{"i eVn
eC5*Q=ai,
/** ZSu.0|0#
* The constructor using fields vYRY?~8 C
* qy|bOl
* @param page {\5(aQ)Vi5
* @param content [ K?
*/ ;^/ruf[t
public Result(Page page, List content){ Rs=Fcvl
this.page = page; 8;gi8Y
this.content = content; [r`KoHwdm
} [WDzaRzd
=%|`gZ
/** 2_pF#M9
* @return Returns the content. #czInXTTx
*/ S#GxKMO%
publicList getContent(){ !l*A3qA
return content; ,g?ny<#o
} M@TG7M7Os
d~8U1}dP
/** Ubu&$4a
* @return Returns the page. })OS2F
*/ ~m=GS[=
public Page getPage(){ I<QUvs%e
return page; v:SHaUS
} Q+1ot,R
8fqabR
/** wKpGJ&
{
* @param content i6paNHi*
* The content to set. 0se%|Z|8
*/ F/2cQ.u2
public void setContent(List content){ tz]0F5
this.content = content; r $S9/
} @_`r*Tb)dM
"[ LUv5
/** g/C 7wc
* @param page |&@q$d
* The page to set. %uo8z~+
*/ j#f/M3
publicvoid setPage(Page page){ OmuE l>
this.page = page; :Pq&l.
} c^= q(V
} 8
o}5QOW
=\]gL%N-|
w5z]=dN
mRx `G(u:v
b_Y+XXb<
2. 编写业务逻辑接口,并实现它(UserManager, 9SeGkwec?$
,P<I<QYu
UserManagerImpl) ?`TJ0("z"
java代码: &m5^
YN$b
L@\t]
~
#N`'hPD}
/*Created on 2005-7-15*/ ]MYbx)v)
package com.adt.service; ;d<XcpK}
TU?n;h#TZ
import net.sf.hibernate.HibernateException; k
Fl*Im
%# uw8V
import org.flyware.util.page.Page; Wqv7
N,w6
import com.adt.bo.Result; q<\r}1Dm
+_:p8,
5o
/** |!K&h(J|
* @author Joa ScJ:F-@>
*/ xd3mAf
publicinterface UserManager { cPIyD?c
L^e*_q2d:>
public Result listUser(Page page)throws 2>"{El|PbN
u0R[TA3
HibernateException; .:H'9QJg
%;4#?.W8
} _3
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"|i1 AR:I
5S? "<+J'
UP-2{zb |?
9>+>s ?IgK
java代码: nxN("$'cq
zpT{!V
|g7)A?2J~
/*Created on 2005-7-15*/ NH/jkt&F[
package com.adt.service.impl; mV]~}7*Y;
<;i&-,
import java.util.List; Z2{$FN
B#."cg4VR
import net.sf.hibernate.HibernateException; C|}yE;*a
' q9Ejig
import org.flyware.util.page.Page; w+rw<,u%
import org.flyware.util.page.PageUtil; '_g&!zi8~
-6 v?iiZr
import com.adt.bo.Result; lU|ltnU
import com.adt.dao.UserDAO; 6Hc25NuQZ
import com.adt.exception.ObjectNotFoundException; 7#
'j>]
import com.adt.service.UserManager; Uj 3{c
F4(;O7j9
/** &[\zs&[@y
* @author Joa &>B|?d
*/ _6FDuCVD-
publicclass UserManagerImpl implements UserManager { *RkvM?o@jC
~=wBF
private UserDAO userDAO; ,hK
=x
mp3 Dc
/** 7TAoWD3
* @param userDAO The userDAO to set. j,,#B4b
*/ WV}pE~
publicvoid setUserDAO(UserDAO userDAO){ p"\-iY]
this.userDAO = userDAO; JKmd'ZGw
} dFeGibI{
*y"|/_
*
/* (non-Javadoc) O'SxTwO
* @see com.adt.service.UserManager#listUser >y+j!)\
\mN?5QCcE
(org.flyware.util.page.Page) p38s&\-kEN
*/ L%9yFg%u
public Result listUser(Page page)throws IKp(KlA
6w<p1qhW
HibernateException, ObjectNotFoundException { UL7%6v{'*
int totalRecords = userDAO.getUserCount(); ~R|fdD/%
if(totalRecords == 0) AF{o=@
throw new ObjectNotFoundException ,^xsdqpe
P\c0Q;){h"
("userNotExist"); YVY(uq)d
page = PageUtil.createPage(page, totalRecords); !oV'
List users = userDAO.getUserByPage(page); LY0/\Z"N
returnnew Result(page, users); etW-gbr
} I |D]NY^
a(o[ bH.|;
} iEFS>kL8e
n O}x,sG2'
jM@@N.
AMgvk`<f
43J8PMY
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 }=3W(1cu-
p|Fhh\,*`X
询,接下来编写UserDAO的代码: G`!;RX
3. UserDAO 和 UserDAOImpl: A&'HlI%J
java代码: 8DrKq]&
(aCl*vV1
J! eVw\6
/*Created on 2005-7-15*/ nfvs"B;
package com.adt.dao; I^A01\p
S67T:ARS
import java.util.List; OaxE3bDT
tX*L_
import org.flyware.util.page.Page; CtDS lJ
PzTTL=G +
import net.sf.hibernate.HibernateException; EZiGi[t7
&4MVk3SLx#
/** : [vp.vw}/
* @author Joa ;lWy?53=@
*/ [dL?N
publicinterface UserDAO extends BaseDAO { -p!KsU
Tf[-8H<
publicList getUserByName(String name)throws M/sqOhg
El&pux2
HibernateException; a( {`<F
&<i>)Ss
publicint getUserCount()throws HibernateException; U7fE6&g
g?o$:>c
publicList getUserByPage(Page page)throws >|I3h5\M
;/{Q4X{
HibernateException; I0jEhg%JZ
Iei4yDv ;
} J&: