Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 @v-^j
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O. * 0;5
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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 v:O{"s
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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 X~{6$J|]#i
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分页支持类: 'HA{6v,y
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java代码: E_,/)U8
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package com.javaeye.common.util; {cK<iQJ
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import java.util.List; CK_dEh2c
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publicclass PaginationSupport { v+ $3
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publicfinalstaticint PAGESIZE = 30; 6N/(cUXJ
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privateint pageSize = PAGESIZE; .:S/x{~
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privateList items; 6)INr,d
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privateint totalCount; ~
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privateint[] indexes = newint[0]; vs@d)$N
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privateint startIndex = 0; Ycr3$n]e
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public PaginationSupport(List items, int mxlh\'b
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totalCount){ WjVBz
setPageSize(PAGESIZE); JVAyiNIH>M
setTotalCount(totalCount); :H}iL*
setItems(items); 8JLf @C:
setStartIndex(0); 1?'4%>kp
} (UkP AE
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public PaginationSupport(List items, int - H?c4? 5
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totalCount, int startIndex){ \/Y(m4<P
setPageSize(PAGESIZE); Nd(,oXa~
setTotalCount(totalCount); !HTOE@
setItems(items); {gD ED
setStartIndex(startIndex); `d <`>
} Q{/z>-X\x
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public PaginationSupport(List items, int j0l{Mc5
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totalCount, int pageSize, int startIndex){ lm`*x=x
setPageSize(pageSize); 54$^ldD
setTotalCount(totalCount); "P !
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setItems(items); ,%pCcM)
setStartIndex(startIndex); d9{lj(2P
} r-qe7K@p
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publicList getItems(){ %"
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return items; }dc0ZRKgx
} I~7iIUD
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publicvoid setItems(List items){ AG(6.
this.items = items; f_k'@e {
} `Vvi]>,cg`
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publicint getPageSize(){ TQR5V\{&%
return pageSize; CJ<nUIy'z
} tZ]gVgZg
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publicvoid setPageSize(int pageSize){ IMM;LC%rD9
this.pageSize = pageSize; z5@XFaQ
} D]~K-[V?l
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publicint getTotalCount(){ &8IBf8
return totalCount;
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} QE]'Dc%
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publicvoid setTotalCount(int totalCount){ Nm)3
if(totalCount > 0){ q1ysT.{p,
this.totalCount = totalCount; )zL@h
int count = totalCount / 4\z@Evm
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pageSize; qda 2
if(totalCount % pageSize > 0) ebA:Sq:w
count++; dIC\U
indexes = newint[count]; ^4sfVpD2!
for(int i = 0; i < count; i++){ 93*csO?Db
indexes = pageSize * p%I)&- 8
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i; &d6@SQ
} =-sTV\
}else{ f-~Y
this.totalCount = 0; ~[CFs'`(2
} ;L-=z]IR,
} Sz5t~U=G
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publicint[] getIndexes(){ M 5#wz0
return indexes; +Tum K.
} oN032o?S
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publicvoid setIndexes(int[] indexes){ 5kHaZ Q
this.indexes = indexes; 217G[YE-
} =j>xu|q
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publicint getStartIndex(){ JM7mQ'`Ud
return startIndex; ?L<B]!9HZt
} ~& -h5=3
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publicvoid setStartIndex(int startIndex){ B&cIx~+
if(totalCount <= 0) 3 =enk0$
this.startIndex = 0; ;!<}oZp{
elseif(startIndex >= totalCount) OnTe_JML
this.startIndex = indexes 5dj" UxH
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[indexes.length - 1]; 3d}v?q78
elseif(startIndex < 0) NQ{(G8x9
this.startIndex = 0; )oIh?-WL
else{ v3r3$(Hr
this.startIndex = indexes ?V6,>e_+
#E]K*mE'
[startIndex / pageSize]; #/>TuJc
} um,f!ho-U
} j_JY[sex
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publicint getNextIndex(){ ggDT5hb
int nextIndex = getStartIndex() + bRvGetX
@&\Y:aRO%i
pageSize; d:)#-x*h7
if(nextIndex >= totalCount) fJS:46
return getStartIndex(); =x<N+vjXY
else dlYpbw}W&<
return nextIndex; K6DN>0sY
} 5Zq
hyv=
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publicint getPreviousIndex(){ `'1g>Ebk0
int previousIndex = getStartIndex() - NO!Qo:
5cPyi/
pageSize; P%2v(
if(previousIndex < 0) 5%}e j)@
return0; ^oi']O
else <r}wQ\F#
return previousIndex; >9H^r\
} ^_]ZZin
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} {SV/AN
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抽象业务类 :a }](Wn
java代码: T.da!!'B
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/** 4)gG_k
* Created on 2005-7-12 x7S\-<8
*/ !Gmnck&+
package com.javaeye.common.business; V,-we|"
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import java.io.Serializable; 3^/w`(-{@
import java.util.List; >V6t
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import org.hibernate.Criteria; r `PJb5^\|
import org.hibernate.HibernateException; wtS*-;W
import org.hibernate.Session; ,ua1sTgQ
import org.hibernate.criterion.DetachedCriteria; B0Df7jr%`>
import org.hibernate.criterion.Projections; LdZVXp^
import )ce 6~
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org.springframework.orm.hibernate3.HibernateCallback; 4p"' ox#
import gkr9+
^MpMqm1?8;
org.springframework.orm.hibernate3.support.HibernateDaoS flCT]ZR
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upport; C5~~$7k0
9L>?N:%5
import com.javaeye.common.util.PaginationSupport; o h{>nwH
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public abstract class AbstractManager extends D
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HibernateDaoSupport { =+iY<~8
@}
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privateboolean cacheQueries = false; QoYEWXT|g
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privateString queryCacheRegion; Kn^+kHh:
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publicvoid setCacheQueries(boolean TsFhrtnx&X
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cacheQueries){ X$!fR >Zc
this.cacheQueries = cacheQueries; }PI:O%N;
} ':n`0+Eh
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publicvoid setQueryCacheRegion(String 4kL6aSqT
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queryCacheRegion){ ek&~A0k_o
this.queryCacheRegion = *H/>96
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queryCacheRegion; PaKa bPY
} =f~<*wQ
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publicvoid save(finalObject entity){ X,49(-~\
getHibernateTemplate().save(entity); {]\7
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} k7U.]#5V
{ {\oC$
publicvoid persist(finalObject entity){ FxlH;'+Q
getHibernateTemplate().save(entity); ZS.=GjK
} RsDSsux
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publicvoid update(finalObject entity){ @V
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getHibernateTemplate().update(entity); f7*Qa!!2p]
} 0)|Z7c&
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publicvoid delete(finalObject entity){ Sn[xI9}O
getHibernateTemplate().delete(entity); l9\W=-'
} neU=1socJ
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publicObject load(finalClass entity, '@Uu/~;h
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finalSerializable id){ vhF9|('G
return getHibernateTemplate().load 9JdJn>
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(entity, id); I7_8oq\3D
} u4hn9**a1
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publicObject get(finalClass entity, >12jU m)
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finalSerializable id){ K3mP 6Z#2
return getHibernateTemplate().get "" UyfC[
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(entity, id); CWeQv9h]X
} (K[e=0Rf
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publicList findAll(finalClass entity){ Ct'tUF<K5
return getHibernateTemplate().find("from &S(>L[)9
:? )!yI
" + entity.getName()); 4Wgzp51Aq!
} pT=^o
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publicList findByNamedQuery(finalString >8/Otg+h
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namedQuery){ .iV=ybMT
return getHibernateTemplate -o~zb-E
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().findByNamedQuery(namedQuery); uNI&U7_"
} C] Fw*t
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publicList findByNamedQuery(finalString query, +7%?p"gEY\
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finalObject parameter){ x"Ll/E)\v]
return getHibernateTemplate Pt85q?- >
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().findByNamedQuery(query, parameter); kL zjK]4 *
} xp1/@Pw?
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publicList findByNamedQuery(finalString query, (LsVd2AbR
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finalObject[] parameters){ z$1|D{
return getHibernateTemplate Vl+UC1M}B>
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h/I
().findByNamedQuery(query, parameters); hRXnig{;3
} @N '_qu
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publicList find(finalString query){ 1^^{;R7N
return getHibernateTemplate().find jS]Saqd
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(query); \
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} I+Fy)=DO9
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publicList find(finalString query, finalObject S8qg"YR
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parameter){ ,]\cf
return getHibernateTemplate().find =xkaF)AW&v
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(query, parameter); [>`.,k
} W'9{2h6u(
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public PaginationSupport findPageByCriteria H,c1&hb/w
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(final DetachedCriteria detachedCriteria){ nZ=[6?
return findPageByCriteria >3g`6d
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); P4)Q5r
} gm5%X'XL
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public PaginationSupport findPageByCriteria 9.xb-m7
{
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(final DetachedCriteria detachedCriteria, finalint >]_6|Wfl
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startIndex){ l'<&H#A;'
return findPageByCriteria PO5,lcBD<
#O_%!7M{4
(detachedCriteria, PaginationSupport.PAGESIZE, M5RN Z%
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startIndex); r1q'+i
} =~D[M)UO|
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public PaginationSupport findPageByCriteria Ma\%uEgTD
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(final DetachedCriteria detachedCriteria, finalint t0cS.hi
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pageSize, 'r=2f6G>cP
finalint startIndex){ W 8`6O2
return(PaginationSupport) kt`ln
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getHibernateTemplate().execute(new HibernateCallback(){ W`LG.`JW
publicObject doInHibernate \="U|LzG
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(Session session)throws HibernateException { O6e$v I@
Criteria criteria = J|jvqt9C
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detachedCriteria.getExecutableCriteria(session); a(IE8:yU`
int totalCount = [ {"x{;
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((Integer) criteria.setProjection(Projections.rowCount &b~X&{3,
cb'Ya_
()).uniqueResult()).intValue(); s8:epcL`A
criteria.setProjection Msvs98LvW
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(null); 5 jK|
List items = (eb65F@ P
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criteria.setFirstResult(startIndex).setMaxResults >~7XBb08
3;b)pQ~6CJ
(pageSize).list(); C &@'oLr
PaginationSupport ps = 1LFad>`
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new PaginationSupport(items, totalCount, pageSize, w9u|E46
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startIndex); @lM-+q(tl
return ps; B]hRYU
} r]}6iF.
}, true); <%^WZ:c
} <% mD#S
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public List findAllByCriteria(final o
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DetachedCriteria detachedCriteria){ <Ed; tq
return(List) getHibernateTemplate 9pi{)PDJ
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().execute(new HibernateCallback(){ @)MG&X
publicObject doInHibernate AzzHpfv,
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(Session session)throws HibernateException { L\#G#1x8
Criteria criteria = O|Vc
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detachedCriteria.getExecutableCriteria(session); N? S;v&q+
return criteria.list(); 'G[G;?F
} H{_D#It
}, true); ~U7Bo(EJp
} qoT&N,/
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public int getCountByCriteria(final xIc||o$
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DetachedCriteria detachedCriteria){ ORqqzy +
Integer count = (Integer) ( +S-
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getHibernateTemplate().execute(new HibernateCallback(){ g<DXJ7o
publicObject doInHibernate _H}hK kG+
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(Session session)throws HibernateException { hb0)<^xu
Criteria criteria = z<P?p
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detachedCriteria.getExecutableCriteria(session); P1L+Vnfu
return D@5h$m5
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criteria.setProjection(Projections.rowCount ~T9QpL1OJ
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()).uniqueResult(); ,[N(XstI
} Q|VBH5}1O
}, true); :
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return count.intValue(); n<)A5UB5-
} 'lEIwJV$
} /EHO(d!<
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用户在web层构造查询条件detachedCriteria,和可选的 '9qyf<MlY
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ut]&3f''
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PaginationSupport的实例ps。 C\Ob!sv%H
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ps.getItems()得到已分页好的结果集
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ps.getIndexes()得到分页索引的数组 W4#DeT
ps.getTotalCount()得到总结果数 ^K8XY@{&
ps.getStartIndex()当前分页索引 AfZGI'%4[a
ps.getNextIndex()下一页索引 UH7?JF-D
ps.getPreviousIndex()上一页索引 %y_pF?2@q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 #;1RStb:zj
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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
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一下代码重构了。 iB~dO @
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我把原本我的做法也提供出来供大家讨论吧: +?Q HSIQo
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首先,为了实现分页查询,我封装了一个Page类: q)@;8Z=_c
java代码: c/F!cW{z^
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/*Created on 2005-4-14*/ 8t7r^[T
package org.flyware.util.page; &liFUP?
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/** c8_,S[W
* @author Joa TgLr4Ex
* ?!c7Zx,(
*/ MCXt,`}[
publicclass Page { 8{%&P%vf
tmeg=U7
/** imply if the page has previous page */ 3fE0cVG*
privateboolean hasPrePage; XCgC^c'
jCx*{TO
/** imply if the page has next page */ 1xsJz^%V
privateboolean hasNextPage; ;<cCT!A
"}[ ]R
/** the number of every page */ OB+ cE4$
privateint everyPage; 1b7?6CqV
P= E10
/** the total page number */ TL-ALtG
privateint totalPage; KZ=5"a
V.+a}J=Cw
/** the number of current page */ Fy>g*3
privateint currentPage; {)kL7>u]^V
wXYT(R
/** the begin index of the records by the current !WB3%E,I
>*|Eyv_
query */ *Hv d
privateint beginIndex; Pc+,iK>
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/** The default constructor */ D-m%eP.
public Page(){ ePSD#kY5
UpiZd/K
} IG%x(\V-e
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/** construct the page by everyPage e9CvdR
* @param everyPage qr*e9Uk^
* */ HuxvIg
public Page(int everyPage){ r$LU$F
this.everyPage = everyPage; Fvnf;']q
} ?f5||^7
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/** The whole constructor */ Vrp]YRL`
public Page(boolean hasPrePage, boolean hasNextPage, D [v22 5
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int everyPage, int totalPage, S!iDPl~
int currentPage, int beginIndex){ #
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this.hasPrePage = hasPrePage; ?]}=4
this.hasNextPage = hasNextPage; D{+D.4\
this.everyPage = everyPage; 1P BnGQYM
this.totalPage = totalPage; [H2su|rBI`
this.currentPage = currentPage; ZS&lXgo
this.beginIndex = beginIndex; nXh<+7
} IJ{VCzi
*@YQr]~
;
/** R^K:hKQ
* @return UyMlk
* Returns the beginIndex. '?$<k@mJW
*/ I
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publicint getBeginIndex(){ LsK
fCB}
return beginIndex; m
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} tU8aPiUl
e.|t12)L "
/** :yOJL [x
* @param beginIndex pQm-Hr78j
* The beginIndex to set. v1NFz>Hx
*/ BK.RYSN
publicvoid setBeginIndex(int beginIndex){ I%0J=V;o{
this.beginIndex = beginIndex; #vR5a}BAk
} %nkbQ2^
A.!3{pAb
/** ?Xp+5{
* @return c,*a|@
* Returns the currentPage. s6oIj$
*/ 368H6 Jj
publicint getCurrentPage(){ s%N6^}N
return currentPage; u/`x@u
} Ap}`Q(.
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/** ^687U,+
* @param currentPage b]WvKdq
* The currentPage to set. r+MqjdXG
*/ :O*62olC5
publicvoid setCurrentPage(int currentPage){ Tz/[P:O3
this.currentPage = currentPage; 49B6|!&I
} tkdyR1-
uF T5Z
/** c+<gc:#jy
* @return _b[Pk;8}j;
* Returns the everyPage. \@7 4I7
*/ &KeD{M%
publicint getEveryPage(){ ZD8E+]+
return everyPage; b$B-LvHd1
} Z
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O$Dj_R#
/** N)YoWA>#bF
* @param everyPage :-b-)*TC;
* The everyPage to set. R9Y{kk0M
*/ JaJyH%+$!
publicvoid setEveryPage(int everyPage){ &([yI>%
this.everyPage = everyPage; \@j3/!=,n%
} &$pA,Gjin\
i]zTY\gw8M
/** uU8L 93
* @return ,j[1!*Z_[
* Returns the hasNextPage. `$r?^|T
*/ ,Q8h#0z r
publicboolean getHasNextPage(){ I#CS;Yh95
return hasNextPage; A)f/ww)Q
} xb^M33-y
(/J %Huy
/** Now2ad&
* @param hasNextPage I]N!cEr;@-
* The hasNextPage to set. MAG/7T5
*/ C2K<CDVw
publicvoid setHasNextPage(boolean hasNextPage){ 3;EBKGg|
this.hasNextPage = hasNextPage; ?)"v~vs
} n,|YJ,v[
/_/Z/D!
/** Hd~fSXFl
* @return <V4"+5cJ8
* Returns the hasPrePage. ^|%7}=e
*/ ?*U:=|
publicboolean getHasPrePage(){ G4,BcCPQ
return hasPrePage; .J9\Fr@
} hmtDw,j
z~yLc{M
/** ZF;s`K)
* @param hasPrePage (FNX>2Mv
* The hasPrePage to set. N_y#Y{c{(
*/ (7}Zh|@W
publicvoid setHasPrePage(boolean hasPrePage){ LQa1p
this.hasPrePage = hasPrePage; wRE2rsXoU
} ;UWp0d%
[AAIBb+U
/** @S Quc
* @return Returns the totalPage. Y/34~lhyl
* }719_DF
*/ <h1J+
publicint getTotalPage(){ &}lRij&`
return totalPage; N'0fB`:kz
}
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Z+! 96LR
/** -<gQ>`(0
* @param totalPage x!9bvQT
* The totalPage to set. ut9R]01:
*/ ZvW&%*k=
publicvoid setTotalPage(int totalPage){ O9MBQNwjA
this.totalPage = totalPage; z%WOv~8~
} `k'Dm:*`u4
B*Q
} C=PV-Ul+
iM s(Ywak]
+P"u1q*+p
e\i}@]
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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 ;JR_z'<
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个PageUtil,负责对Page对象进行构造: :<E\&6# oC
java代码: ZUeA&&{
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/*Created on 2005-4-14*/ A/*h[N+2!
package org.flyware.util.page; *Ja,3Qq
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import org.apache.commons.logging.Log; n(el
import org.apache.commons.logging.LogFactory; :Nw7!fd
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/** -*&C "%e
* @author Joa N!=Q]\ZD
* 5[>N[}Ck>
*/ dZjh@yGP.
publicclass PageUtil { ,zrShliU
%Z6\W;
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privatestaticfinal Log logger = LogFactory.getLog Zl`sY5{1
N`i`[ f
(PageUtil.class); %c,CfhEV%&
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/** 7!E7XP6,~>
* Use the origin page to create a new page E 5bo60z
* @param page v@E/?\k"
* @param totalRecords |oJ R+
* @return v_ W03\
*/ Y@M
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publicstatic Page createPage(Page page, int rlVo}kc7:
i"C?6R
totalRecords){ pNR69/wGi
return createPage(page.getEveryPage(), 1`8(O >5
oq }Q2[.b
page.getCurrentPage(), totalRecords); vH9Gf
} t>>\U X
+S>}<OE
/** (L6*#!Dt
* the basic page utils not including exception AehkEN&H/t
@](\cT64i3
handler r<L>~S>yb
* @param everyPage ='|HUxFi
* @param currentPage jF%[.n[BU
* @param totalRecords ;Cqjg.wkB
* @return page N?;5%pG
<
*/ B[Fuy y?
publicstatic Page createPage(int everyPage, int eFeWjB'<7
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currentPage, int totalRecords){ az ?2
everyPage = getEveryPage(everyPage); $C !Mk
currentPage = getCurrentPage(currentPage); }8qsE
int beginIndex = getBeginIndex(everyPage, GCEq3
^/
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currentPage); 4$!iw3N(
int totalPage = getTotalPage(everyPage, ec` $2u
tpi>$:e
totalRecords); spt='!)4
boolean hasNextPage = hasNextPage(currentPage, n/]$k4h
~_Mz05J-\_
totalPage); IW'2+EGc
boolean hasPrePage = hasPrePage(currentPage); iy_\1jB0
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returnnew Page(hasPrePage, hasNextPage, 5=.EngG
everyPage, totalPage, q#~]Hp=W5
currentPage, 35[8XD
X K5qE"
beginIndex); =
A !;`G
} t7p`A8&
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privatestaticint getEveryPage(int everyPage){ R?Or=W)i
return everyPage == 0 ? 10 : everyPage; ~:%rg H
} |cBpX+D
*AU"FI>V
privatestaticint getCurrentPage(int currentPage){ NK@G0p~O
return currentPage == 0 ? 1 : currentPage; &`'gO
9
} O$=)
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privatestaticint getBeginIndex(int everyPage, int 8\^[@9g3\3
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currentPage){ k(;c<Z{?1
return(currentPage - 1) * everyPage; ^f,('0p->
} XHlx89v7
vK\;CSk
privatestaticint getTotalPage(int everyPage, int oGLSk(T&I
K>`7f]?H*e
totalRecords){ E@_M|=p&
int totalPage = 0; nJ4CXSdE
e1RtoNF ^
if(totalRecords % everyPage == 0) ;U|^Tsuc`
totalPage = totalRecords / everyPage; h?:lO3)TL=
else zAxwM-`
totalPage = totalRecords / everyPage + 1 ; THmX=K4=?
ZK[S'(6q
return totalPage; }hFjl4`xa
} E5M*Gs
),-4\!7
privatestaticboolean hasPrePage(int currentPage){ 6tbH(
return currentPage == 1 ? false : true; Ir*,fyl
} {Z_Pry$6
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privatestaticboolean hasNextPage(int currentPage, /.\$%bua
66%#$WH#
int totalPage){ 8F<Qc*'
return currentPage == totalPage || totalPage == X3:-+]6,d
j]"Yzt~u
0 ? false : true; UP]J`\$o
} m GWT</=[$
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} <bf^'$l
ud`.}H~aB
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t$=0 C
m//(1hWv7
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。 VB 8t"5
+6!.)Ea=
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 e3wFi,/@
5CkM0G`
做法如下: P$)9osr
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 x
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56o?=|
的信息,和一个结果集List: m)q;eQs
java代码: (iK0T.
,FJ9C3
X./4at`
/*Created on 2005-6-13*/ >:s.`jV<
package com.adt.bo; VYhZ0;' '
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import java.util.List; h.QKbbDj
,7pO-:*g
import org.flyware.util.page.Page; HFx8v!^5N
'8>#`Yba
/** T"Wq:
* @author Joa )*^PMf
*/ -[a0\H
publicclass Result { h"YIAQ',
d*1@lmV*
private Page page; / vge@bsE
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private List content; 0}Xkj)R,
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/** "0g1'az}
* The default constructor &K`[SX=
*/ $xS `i-|
public Result(){ ?/{
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super(); A{;b^IK
} ;=Bf&hY&
;=6++Oq
/** 6[c
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* The constructor using fields $+ZO{
(
* ,KIa+&vJW@
* @param page 0ldde&!p
* @param content g?i_10Xlp
*/ `a2Oj@jP
public Result(Page page, List content){ C>@~W(IE
this.page = page; RN3w{^Ll
this.content = content; |zvxKIW;wd
} R6)p4#|i
5D]%E?ag
/** cCU'~
* @return Returns the content. *Yvfp{B
*/ mb?DnP,z
publicList getContent(){ ,+*8@>c
return content; &.o}(e:]
} #0L:h?L
CQ"IL;y
/** ygUvO3Z
* @return Returns the page. S,3e|-&$
*/ Y.i<7pBt
public Page getPage(){ akBR"y:~:H
return page; PQvq$|q
} 60teD>Eh,
JO7IzD\
/** ~?-U
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* @param content KL.{)bi
* The content to set. rgIJ]vmy<H
*/ [4Glt>Nj>
public void setContent(List content){ *xU^e`P
this.content = content; 68)z`JI|<)
} Si*Pi
p4Vw`i+DnH
/** \D, 0
* @param page p`Omcl~Q
* The page to set. Fdu0?H2TL
*/ #&r^~>,#L-
publicvoid setPage(Page page){ m]N4.J
this.page = page; %r6~5_A
} A0O$B7ylQ
} (rZq0*
in#qV
{E6b/G?Q
)@1_Dm@0b
xfO!v>
2. 编写业务逻辑接口,并实现它(UserManager, kZ`60X%wE
$hndb+6q
UserManagerImpl) U@m<
java代码: 2d<ma*2n(
>0@X^o
;N ]ElwP
/*Created on 2005-7-15*/ evg i\"
package com.adt.service; cy^6g?ew
%Dsa
~{
import net.sf.hibernate.HibernateException; fgn*3 pg
y"$|?187x
import org.flyware.util.page.Page; xC<OFpI\
fRaVY`|wK
import com.adt.bo.Result; Jev@IORN\
\^N9Q9{7]
/** q*Ns]f'a
* @author Joa o~<fw]y
*/ 7ou2SL}k
publicinterface UserManager { 7i334iQZ
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m
public Result listUser(Page page)throws vWe)c J
A8c'CMEm
HibernateException; C&<f YCwG
)]>=Uo
} 4vBZb^W;9
qh F/iUE
:Nc~rOC_
^x4,}'(
1v`<Vb%"}T
java代码: SGNi~o
JguE#ob2
QnaMjDh$6
/*Created on 2005-7-15*/ 7:M%w'oR
package com.adt.service.impl; ,@Ed)Zoh
"~d)$]+
import java.util.List; [u)^QgP
l4;/[Q>Z
import net.sf.hibernate.HibernateException; R8o9$&4_
2R2Z6}
import org.flyware.util.page.Page; u^ngD64
import org.flyware.util.page.PageUtil; 8.Y6r
tJHzhH)
import com.adt.bo.Result; L8 R|\Bx
import com.adt.dao.UserDAO; l<7 b
import com.adt.exception.ObjectNotFoundException; X5>p~;[9
import com.adt.service.UserManager; 20% xD e
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/** er l_Gg
* @author Joa :Q?xNY%
*/ & r\z9!
publicclass UserManagerImpl implements UserManager { ub,Sj{Mq"
wG^{Jf&@$
private UserDAO userDAO; 5"XcVH4g
V)N9V|O'
/** IWm|6@y
* @param userDAO The userDAO to set. aeH
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*/ 7|,5;
publicvoid setUserDAO(UserDAO userDAO){ !R)v2Mk|
this.userDAO = userDAO; UnW,|n8
} R['qBHQ?
_4%+TN6z
/* (non-Javadoc) V\ARe=IWM
* @see com.adt.service.UserManager#listUser 8
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(org.flyware.util.page.Page) j24BB}mBB
*/ DOU\X N
public Result listUser(Page page)throws X`J~3s
g<UjB
HibernateException, ObjectNotFoundException { G9Xrwk<g4
int totalRecords = userDAO.getUserCount(); YdE$G>&em
if(totalRecords == 0) d['BtVJ
throw new ObjectNotFoundException i/)Uj-*G)
/7P4[~vw
("userNotExist"); lXv{+ic
page = PageUtil.createPage(page, totalRecords); "V?U^L>SF
List users = userDAO.getUserByPage(page); \i`/k(
returnnew Result(page, users); E8FS jLZ
} ZZl)p\r
eT}c_h)
} JRU)AMMU&
tOp>OoD
<5C3c&sds
4\Q ?4ZX
']}ZI 8
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 aQinR"o
g w}t.3}
询,接下来编写UserDAO的代码: +uv]dD*i
3. UserDAO 和 UserDAOImpl: 70|Cn(p_
java代码: 6\b B#a
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oEKLuy
/*Created on 2005-7-15*/ ,/o<O jR
package com.adt.dao; M@8
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=_
import java.util.List; kS=OX5
EkjO4=~UC
import org.flyware.util.page.Page; roW8 4x
s:;!QIC5jo
import net.sf.hibernate.HibernateException; nuKjp Ap!
b.C!4^
/** ;uDH&3W
* @author Joa #Q$9Eq8"[
*/ UKk~)Of
publicinterface UserDAO extends BaseDAO { |*OS;FD5
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publicList getUserByName(String name)throws (y#8z6\dx
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HibernateException; 8~rD#8`6j
I.q nA
publicint getUserCount()throws HibernateException; A9$q;8= <
*Pw;;#\B
publicList getUserByPage(Page page)throws ,Qj7wFZ
!:rQ@PSy9
HibernateException; 8n);NZ
x*bM C&Ea
} KcNEB_i
\gj@O5rG P
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s?E7tmaM
V><5N;w
java代码: &W`yHQ"JY
e[w)U{|40
"E8-76n
/*Created on 2005-7-15*/ DghX(rs_
package com.adt.dao.impl; V:My1R0
<E$5LP;:
import java.util.List; 'S@C,x%2,
ldi'@^
import org.flyware.util.page.Page; y=5s~7]
x1Z?x,-D"
import net.sf.hibernate.HibernateException; N7}.9%EV
import net.sf.hibernate.Query; N<Ti[Q]G
!t~S.`vF
import com.adt.dao.UserDAO; 3vNo D
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/** Mq6.!j
* @author Joa .CrahV1G
*/ }_gCWz-5?
public class UserDAOImpl extends BaseDAOHibernateImpl a|TP 2m
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implements UserDAO { 3V LwMF?
I)Lg=n$
/* (non-Javadoc) 9[6xo!
* @see com.adt.dao.UserDAO#getUserByName i&{8a3B
*sZOws<
(java.lang.String) Ok2k;
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*/ D|`[ [
publicList getUserByName(String name)throws lj'c0k8
<iJ->$
HibernateException { )#IiHBF
String querySentence = "FROM user in class xREqcH,vU
@6}c\z@AxM
com.adt.po.User WHERE user.name=:name"; mi%d([)%<
Query query = getSession().createQuery YNHn# 98\
w*$nG$
(querySentence); sqj8c)6
query.setParameter("name", name); 5pE[}@-c9
return query.list(); T~=NY,n
} 2vu"PeU9
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/* (non-Javadoc) $PHKI B(
* @see com.adt.dao.UserDAO#getUserCount() Y@_ i32,r
*/
4\dc
publicint getUserCount()throws HibernateException { 1MX:^L!f8
int count = 0; zrD$loaW.'
String querySentence = "SELECT count(*) FROM .+|G`*1<i
&6r".\;^
user in class com.adt.po.User"; n=L;(jp<j
Query query = getSession().createQuery +cQ4u4
u5$\E]+_
(querySentence); q8P| ]
count = ((Integer)query.iterate().next =ni&*&
1LT)%_d@
()).intValue(); Y-gjX$qGo
return count; z#8GF^U:T
} n M,m#"AI
W446;)?5
/* (non-Javadoc) @,pO%,E6
* @see com.adt.dao.UserDAO#getUserByPage l4|bpR Cp
Uj1^?d+b
(org.flyware.util.page.Page) dB^J}_wp
*/ W^60BZ
publicList getUserByPage(Page page)throws n"(n*Hf7b
.LN&EfMenF
HibernateException { +, p
String querySentence = "FROM user in class L8TT54fM
u}qfwVX Z
com.adt.po.User"; Uk6Y6mU V
Query query = getSession().createQuery 91jv=>=DM
P/,7CfyPd
(querySentence); ;BejFcb
query.setFirstResult(page.getBeginIndex()) VKS:d!}3E
.setMaxResults(page.getEveryPage()); `-qSvjX
return query.list(); 8!4=j
} &