Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 z7ik/>d?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 J\r\_P@;c
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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 QJ3#~GYNr
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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 P{--R\
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分页支持类: 4%^z=%
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java代码: 755,=U8'wi
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package com.javaeye.common.util; TIKkS*$
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import java.util.List; uhh7Ft#H
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publicclass PaginationSupport { Qz,2PO
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publicfinalstaticint PAGESIZE = 30; &h0LWPl
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privateint pageSize = PAGESIZE; kU[hB1D5
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privateList items; ^o{{kju
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privateint totalCount; "esuLQC
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privateint[] indexes = newint[0]; &t[[4+Qt
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privateint startIndex = 0; UDh\%?j
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public PaginationSupport(List items, int gS5REC4I/
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totalCount){ KClkPL!jP
setPageSize(PAGESIZE); LUbj^iQ9
setTotalCount(totalCount); DjM*U52Yfj
setItems(items); sfyLG3$/
setStartIndex(0); NX&dJ
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} He(65ciT<O
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public PaginationSupport(List items, int Nvgi&iBh8
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totalCount, int startIndex){ Q>, &@
setPageSize(PAGESIZE); Hz.i $L0}
setTotalCount(totalCount); t1Fqq4wRi
setItems(items); xoKK{&J
setStartIndex(startIndex); 7GOBb|
} -G.N
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public PaginationSupport(List items, int rGP;0KtQ
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totalCount, int pageSize, int startIndex){ dd
setPageSize(pageSize); V: D;?$Jl
setTotalCount(totalCount); "V' r}>
setItems(items); &DWSf`:Hx
setStartIndex(startIndex); LDr?'M!D
} e*2^
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publicList getItems(){ AioW*`[WjA
return items; ij$NTY=u
} YVMvT>/,
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publicvoid setItems(List items){ +MX~1RU+
this.items = items; zR<{z
} ^Kz?SO
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publicint getPageSize(){ 8\rca:cF
return pageSize; #yochxF_
} f)*?Ji|5F
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publicvoid setPageSize(int pageSize){ dPEDsG0$a
this.pageSize = pageSize; 5p#0K@`n/
} ESCN/ocV
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publicint getTotalCount(){ #kv9$
return totalCount; 8g0 #WV
} 6TW<,SM
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publicvoid setTotalCount(int totalCount){ IU8zidn&
if(totalCount > 0){ cb^IJA9}
this.totalCount = totalCount; $5i\D
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int count = totalCount / ~^2w)-N
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pageSize; oJTEN}fL
if(totalCount % pageSize > 0) Ak?9a_f
count++; N|yA]dg[
indexes = newint[count]; VeWh9:"bJ
for(int i = 0; i < count; i++){ jlBsm'M<m
indexes = pageSize * M7/5e3
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i; RnkV)ed(
} zIF1A*UH
}else{ hl:Ba2_E
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this.totalCount = 0; hoFgs9
} !V.]mI
} MLV]+H[mt
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publicint[] getIndexes(){ oDZZ
return indexes; \^(#b,k#
} ?Z{/0X)]|
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publicvoid setIndexes(int[] indexes){ ?ES{t4"
this.indexes = indexes;
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} eQ'E`S_d
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publicint getStartIndex(){ Yb5U^OjyJ
return startIndex; e8`d<U
} 4BMu0["6|s
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publicvoid setStartIndex(int startIndex){ "o--MBq4
if(totalCount <= 0) 0aY|:
this.startIndex = 0; :$G^TD/n
elseif(startIndex >= totalCount) &E]) sJ0
this.startIndex = indexes %Ik5|\ob?
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[indexes.length - 1]; ;j T{<
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elseif(startIndex < 0) 12
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this.startIndex = 0; %1{S{FB
else{ .uA
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this.startIndex = indexes %`$bQU
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[startIndex / pageSize]; l iY/BkpH
} @{IX
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} 570ja7C:
oT}$N_gFT
publicint getNextIndex(){ d[h=<?E5
int nextIndex = getStartIndex() + c^_+<C-F
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pageSize; 7oE:]
if(nextIndex >= totalCount) j/Kul}Ml\*
return getStartIndex(); '@ 24<T]
else k
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return nextIndex; I]HYqI
} Oyb9
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publicint getPreviousIndex(){ |~76dxU
int previousIndex = getStartIndex() - I_B%F#X)
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pageSize; /*g0M2+OZo
if(previousIndex < 0) eF;Jj>\R+i
return0; # 9bw'm
else CM~x1f *v
return previousIndex; f:8!@,I
} =&g:dX|q8
@[D5{v)S
} \&d1bq
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抽象业务类 *vNAm(\N
java代码: p+Yy"wH:h{
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/** Fp B3SJ6 B
* Created on 2005-7-12 klmbbLce
*/ D8k >f ]
package com.javaeye.common.business; aAcQmq TT
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import java.io.Serializable; ke6,&s%{j
import java.util.List; 5aVZ"h"
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import org.hibernate.Criteria;
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import org.hibernate.HibernateException; Ozqh Jb
import org.hibernate.Session; {dh@|BzsbH
import org.hibernate.criterion.DetachedCriteria; Wu,=jL3?$A
import org.hibernate.criterion.Projections; /?>W\bP<
import f3;[ZS
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org.springframework.orm.hibernate3.HibernateCallback; UnDX .W*2
import 6ZjUC1
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org.springframework.orm.hibernate3.support.HibernateDaoS de8xl
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upport; )"Ujx`]4r
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import com.javaeye.common.util.PaginationSupport; ./tZ*sP:
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public abstract class AbstractManager extends G_WFg$7G%
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HibernateDaoSupport { fG?a"6~
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privateboolean cacheQueries = false; uKY1AC__
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privateString queryCacheRegion; CT\rx>[J.6
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publicvoid setCacheQueries(boolean n1x3q/~
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cacheQueries){ rZAP3)dA
this.cacheQueries = cacheQueries; 9G1ZW=83
} zl, Vj%d
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publicvoid setQueryCacheRegion(String 6XAofN/5f
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queryCacheRegion){ &i805,lx
this.queryCacheRegion = ?J|
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queryCacheRegion; D=f$-rn
} B<|Vm.D
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publicvoid save(finalObject entity){ B0g?!.#23
getHibernateTemplate().save(entity); TCgW^iu
} {iQ4jJ`n
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publicvoid persist(finalObject entity){ Wa!C2nB
getHibernateTemplate().save(entity); -lfbn=3
} {rF9[S"h
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publicvoid update(finalObject entity){ &?j\=%
getHibernateTemplate().update(entity); Cpn!}!Gnf
} do l8O
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publicvoid delete(finalObject entity){ SJ,];mC0
getHibernateTemplate().delete(entity); D;:p6q}hT
} l?X)]1
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publicObject load(finalClass entity, "?_af
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finalSerializable id){ X=jD^"-
return getHibernateTemplate().load !6 kn>447Y
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(entity, id); H-%
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} WxJaE;`Ige
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publicObject get(finalClass entity, .8|"@
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finalSerializable id){ i"^ yy+
return getHibernateTemplate().get 7 $Cv=8
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(entity, id); MbQ%'z6D
} WQ{^+C9g'1
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publicList findAll(finalClass entity){ (V}?y:)
return getHibernateTemplate().find("from )ItW}1[I
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" + entity.getName()); 7<*g'6JG[
} |lIgvHgg
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publicList findByNamedQuery(finalString H=XdgOui
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namedQuery){ 0,cU^HMA
return getHibernateTemplate %mS>v|
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().findByNamedQuery(namedQuery); MMQ\V(C
} 0Y!~xyg/
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publicList findByNamedQuery(finalString query, EQy~ ^7V B
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finalObject parameter){ (Kw%fJT
return getHibernateTemplate {P ==6/<2o
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().findByNamedQuery(query, parameter); .07kG]
} [KEw5-=i@
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publicList findByNamedQuery(finalString query, z|<?=c2P
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finalObject[] parameters){ b:x~Jz#%2
return getHibernateTemplate 8wCB}q C
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().findByNamedQuery(query, parameters); Rz<'&Z>;
} "!#KQ''R
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publicList find(finalString query){ q^}iXE~
return getHibernateTemplate().find G,b*Qn5#
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(query); EiPOY'
} C jz(-018
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publicList find(finalString query, finalObject ?0d#O_la3
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parameter){ $F@ ,,*
return getHibernateTemplate().find 5"L.C32
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(query, parameter);
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} e'3y^Vg
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public PaginationSupport findPageByCriteria %\1W0%w
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(final DetachedCriteria detachedCriteria){ ,UxAHCR~9
return findPageByCriteria *3(mNpi{_
<@>l9_=R
(detachedCriteria, PaginationSupport.PAGESIZE, 0); }4q1"iMlO
} N3\vd_D(
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public PaginationSupport findPageByCriteria u y13SkW
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(final DetachedCriteria detachedCriteria, finalint 'On%p|s)H
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startIndex){ WS\Ir-B
return findPageByCriteria S3y('
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(detachedCriteria, PaginationSupport.PAGESIZE, Hw,@oOh.
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startIndex); pE{Ecrc3|
} B#o6UO\
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public PaginationSupport findPageByCriteria :;w#l"e7<
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(final DetachedCriteria detachedCriteria, finalint 4
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pageSize, Wfsd$kN6{
finalint startIndex){ |u#7@&N1
return(PaginationSupport) Z)<lPg!YAR
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getHibernateTemplate().execute(new HibernateCallback(){ ;esOe\zjE
publicObject doInHibernate HDj260a
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(Session session)throws HibernateException { V=H :`n3k
Criteria criteria = Bm+Ca:p%
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detachedCriteria.getExecutableCriteria(session); 5jsZJpk$
int totalCount = wB"`lY
C/q!!
((Integer) criteria.setProjection(Projections.rowCount 3 ]pHc)p!.
se29IhS!e
()).uniqueResult()).intValue(); #l!nBY ~
criteria.setProjection [6\b(kS+
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(null); a" L9jrVrw
List items = sY&Z/Y
G
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criteria.setFirstResult(startIndex).setMaxResults IJD E{)
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(pageSize).list(); ~P'i
/*:
PaginationSupport ps = qTe@?j
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new PaginationSupport(items, totalCount, pageSize, {=ATRwUL
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startIndex); wQ81wfr1:
return ps; A}(o1wuw
} FzG>iC}
}, true); %RzCJxT
} EKEJ9Y+47H
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public List findAllByCriteria(final cVDcda|PE
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DetachedCriteria detachedCriteria){ _7'5I A
return(List) getHibernateTemplate upGLZ#
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().execute(new HibernateCallback(){ xcH&B%;f
publicObject doInHibernate #tA/)Jvi
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(Session session)throws HibernateException { }d%Fl}.Ez
Criteria criteria = 9^@)R
ED
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detachedCriteria.getExecutableCriteria(session); o_03Io
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return criteria.list(); \susLD
} wYQEm
}, true); od^ylg>K
} w[AL'1s]
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public int getCountByCriteria(final 0B:
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DetachedCriteria detachedCriteria){ ]`M2Kwp
Integer count = (Integer) "Cs36k
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getHibernateTemplate().execute(new HibernateCallback(){ .aR9ulS
publicObject doInHibernate /y(0GP4A
q}W})
(Session session)throws HibernateException { HEw&'
Criteria criteria = ~ 7<M6F
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detachedCriteria.getExecutableCriteria(session); BAtjYPX'w
return L+}<gQJ(
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criteria.setProjection(Projections.rowCount ^!gq_x
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()).uniqueResult(); /i#";~sO
} 2+ywl}9
}, true); ?hViOh$.
return count.intValue(); [v`kqL~
} :aH5=@[!y
} ~0@fK<C)O
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用户在web层构造查询条件detachedCriteria,和可选的 h`iOs>
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 u08QE,
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PaginationSupport的实例ps。 (e0(GOqf4
KC)}Mzt6_
ps.getItems()得到已分页好的结果集 r-.>3J
ps.getIndexes()得到分页索引的数组 YrV@k*O*
ps.getTotalCount()得到总结果数 :>U+HQll
ps.getStartIndex()当前分页索引 E;[Uhh|78!
ps.getNextIndex()下一页索引 dT[JVl+3=
ps.getPreviousIndex()上一页索引 pTXF^:8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Np aS2q-d
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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 !F.h+&^D;
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一下代码重构了。 Qj*.Z4ue
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我把原本我的做法也提供出来供大家讨论吧: jFUpf.v2
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首先,为了实现分页查询,我封装了一个Page类: FRQ0t!b<M1
java代码: D:/q<<|
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/*Created on 2005-4-14*/ *l=(?Pe<
package org.flyware.util.page; Eku9u
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/** s^K2,D]P
* @author Joa hidQO h
* zo8D"
*/ 1GqSY|FSGp
publicclass Page { r$8'1s37`
P=_fYA3
/** imply if the page has previous page */ 4QTHBT+2`
privateboolean hasPrePage; tRZ4\Bu
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/** imply if the page has next page */ m uy^>2p
privateboolean hasNextPage; Q$v00z]f*
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/** the number of every page */ {/H<_
privateint everyPage; CS~_>bn
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/** the total page number */ ts9wSx~[+
privateint totalPage; a[ayr$Hk?
^
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/** the number of current page */ "r*`*1
privateint currentPage; Q;g7<w17
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/** the begin index of the records by the current &N._}ts
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query */ &T~X`{V]`
privateint beginIndex; @OkoT:
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/** The default constructor */ ;o9ixmT<-o
public Page(){ \~"Ub"~I
v"W*@7<`S
} "~^0
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/** construct the page by everyPage doOuc4
* @param everyPage *=.~PR6W{
* */ }Sbk qd5
public Page(int everyPage){ pCA`OP);=
this.everyPage = everyPage; IEMa/[n/
} -v.\W y~\
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/** The whole constructor */ KE@+I.x
public Page(boolean hasPrePage, boolean hasNextPage, 5a$EXV
Hd\V?#H
V`1{*PrI@L
int everyPage, int totalPage, U/^#nU.,
int currentPage, int beginIndex){ 6]Is"3ca
this.hasPrePage = hasPrePage; ^n(FO,8c
this.hasNextPage = hasNextPage; D2kmBZ3
this.everyPage = everyPage; uVCH<6Cp
this.totalPage = totalPage; S`U8\KTi
this.currentPage = currentPage; o3/o2[s
this.beginIndex = beginIndex; #-<Go'yF
} 4&sf{tI
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/** ^2nrA pF
* @return %,_ZVgh0
* Returns the beginIndex. Xt<1b
*/ lz~^*\ F
publicint getBeginIndex(){ %DYh<U4N
return beginIndex; "(7y%TFt:
}
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/** Syy{ ^Ae}
* @param beginIndex rZJJ\ , |
* The beginIndex to set. {tUe(
*/ CqlxE/|
publicvoid setBeginIndex(int beginIndex){ KE~Q88s
this.beginIndex = beginIndex; uR5+")r@S
} kpIn_Ea
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/** G?'^"ae"Z
* @return gVfFEF.
* Returns the currentPage. _ZK^JS
*/ N*}soMPV^.
publicint getCurrentPage(){ N68$b#9Ry
return currentPage; k`8O/J
} !SW0iq[7j
<@KIDZYC
/** <&l$xn
* @param currentPage MmN{f~Kq9
* The currentPage to set. #0aBQ+_8H
*/ eTvWkpK+
publicvoid setCurrentPage(int currentPage){ ;+E]F8G9r
this.currentPage = currentPage; '7sf)0\:<p
} PJC(:R(j
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/** x?{UWh%
* @return pqb'L]
* Returns the everyPage. Op ar+|p\
*/ k77 3h`;
publicint getEveryPage(){ ES&u*X:
return everyPage; 7qB4_
} 1"ZtE\{
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/** k
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* @param everyPage =#Sw.N
* The everyPage to set. w5HIR/kP
*/ m7'<k1#"Y
publicvoid setEveryPage(int everyPage){ UJI2L-;Ul
this.everyPage = everyPage; 6MT
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} B@&sG
5ES
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/** ~~OFymQ%?q
* @return CW
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* Returns the hasNextPage. *#XZ*Ga
*/ '6dVe2V
publicboolean getHasNextPage(){ Snf_{A<
return hasNextPage; gM3:J:N
} e.n(NW
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/** 1 P!)4W
* @param hasNextPage
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* The hasNextPage to set. mZR3Hl$
*/ 2e1KF=N+
publicvoid setHasNextPage(boolean hasNextPage){ 6WY/[TC-
this.hasNextPage = hasNextPage; @=Q!a (g
} XGx[Ny_A2
*vD.\e~
/** 5CFNBb%Xy
* @return Qu61$!
* Returns the hasPrePage. nnv|GnQST
*/ q*3OWr
publicboolean getHasPrePage(){ {JgY-#R?{(
return hasPrePage; gm-[x5O"
} WPL@v+
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/** Jp=fLo 9
* @param hasPrePage xQu|D>kv87
* The hasPrePage to set. JI5o~;}m
*/ t@qf/1
publicvoid setHasPrePage(boolean hasPrePage){ rL{R=0
this.hasPrePage = hasPrePage; N y'\Q"Y]
} .T'@P7Hdx
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/** 3PNdc}h
* @return Returns the totalPage. YZg#H)w%
* faQmkO
*/ !RI _Uph
publicint getTotalPage(){ |3'
return totalPage; 7Z< ~{eD,
} FDz`U:8
HT;^u"a~
/** ljKIxSvCFp
* @param totalPage +X=*>^G(-
* The totalPage to set. Y,}_LS$f
*/ Jl/w P
publicvoid setTotalPage(int totalPage){ =fcg4h5(
this.totalPage = totalPage; KxkBP/`3Q
} yq%5h[M
u.GnXuax
} 1r;zA<<%R
*&NP?-E
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F` U~(>u'
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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 >pv.,cj
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个PageUtil,负责对Page对象进行构造: ~bLx2=-"
java代码: \R#SoOd
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/*Created on 2005-4-14*/ W;vNmg}mn
package org.flyware.util.page; = s&Rk~2b/
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import org.apache.commons.logging.Log; +hyOc|5
import org.apache.commons.logging.LogFactory; ^m qEKy<
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2!
/** }s~c(sL?;
* @author Joa Y sM*d
* |b
*/ SI}s
publicclass PageUtil { E/zf9\
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privatestaticfinal Log logger = LogFactory.getLog ]@{Lx>Oh"
my?Ly(#
(PageUtil.class); IVR%H_uz
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/** 9kL,69d2
* Use the origin page to create a new page bv+u7B6,
* @param page ){;XI2
* @param totalRecords b,xZY1a
* @return Xh9QfT ,
*/ g>lZs
publicstatic Page createPage(Page page, int ?KC(WaGJQ
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totalRecords){ t3;Zx+Br
return createPage(page.getEveryPage(), }%|ewy9|CW
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page.getCurrentPage(), totalRecords); .GrOdDK$ns
} `/8@Fj
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/** '75T2Ud
* the basic page utils not including exception i>m%hbAk
pQz1!0
handler &hOz(825r
* @param everyPage -%asHDQ{
* @param currentPage p*
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* @param totalRecords }3(!kW
* @return page )Qbd/zd\U
*/ XqTguO'
publicstatic Page createPage(int everyPage, int G/_IY;
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currentPage, int totalRecords){ D-gH_ff<]9
everyPage = getEveryPage(everyPage); fkV@3sj
currentPage = getCurrentPage(currentPage); gaF6j!p
int beginIndex = getBeginIndex(everyPage, o<G 9t6~
}9fa]D-a?
currentPage); /_C2O"h
int totalPage = getTotalPage(everyPage, =nEP:7~{
4E$MhP
totalRecords); 1!#N-^qk
boolean hasNextPage = hasNextPage(currentPage, `Q@7,z=f
M(-)\~9T
totalPage); Ca2r<|uA
boolean hasPrePage = hasPrePage(currentPage); LPvp
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returnnew Page(hasPrePage, hasNextPage, fQ<sq0'e\
everyPage, totalPage, RZa/la*
currentPage, [|(|"dh@^H
mQ[$U
beginIndex); <FT7QO$I
} yJA~4
+}:Z9AAMy
privatestaticint getEveryPage(int everyPage){ S$mv(C
return everyPage == 0 ? 10 : everyPage; !=[Y yh
} ;+Jx,{)
0Hnj<| HL
privatestaticint getCurrentPage(int currentPage){ 8D*7{Q
return currentPage == 0 ? 1 : currentPage; 1.3#PdMR,
} q
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M:+CW;||!
privatestaticint getBeginIndex(int everyPage, int ,-UF5U
KOcB#UHJ
currentPage){ Bkcwl
return(currentPage - 1) * everyPage; z*.AuEK?
} aKI"<%PNn
y=3 dGOFB
privatestaticint getTotalPage(int everyPage, int P>/:dt'GJ}
o@meogkL
totalRecords){ Ymut]`dX
int totalPage = 0; @C;1e7
+f3Rzx]
if(totalRecords % everyPage == 0) opcanl9pSW
totalPage = totalRecords / everyPage; Hm-#Mpw
else YI0
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totalPage = totalRecords / everyPage + 1 ; h]4xS?6O
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return totalPage; jv)+qmqo!
} bvox7V>
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privatestaticboolean hasPrePage(int currentPage){ ~1G^IZ6
return currentPage == 1 ? false : true; ptCF))Zm'
} \:vF FK4a
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privatestaticboolean hasNextPage(int currentPage, Ot=>~(u0
.3
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int totalPage){ ;n&95t1$
return currentPage == totalPage || totalPage == 8_Oeui(i
"j>X^vn
0 ? false : true; s^kG]7
} #:)'D?,
@*;x1A-]V
wkg4I.
} |#Gxqq'
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1|
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。 qCs/sW
=G-OIu+H!U
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 oo'9ZE/%
]ch=@IV
做法如下: )nN!% |J
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 GS;GJsAs
^y5A\nz&
的信息,和一个结果集List: PGTEIptX7
java代码: 7oZ:/6_>
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6H#:rM
/*Created on 2005-6-13*/ wE
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package com.adt.bo; VU3RFl
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import java.util.List; mxlh\'b
Xaz "!
import org.flyware.util.page.Page; zIa={tU
;dIk$_FN
/** mWviWHK
* @author Joa %i9S"
*/ !6/UwPs
publicclass Result { E$"NOR
@@Ib^sB%
private Page page; ?9 huuJs7
AR |4^
private List content; 91R#/i
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/** d`sZ"8}j
* The default constructor vC]X>P5 Px
*/ *byUqY3(
public Result(){ i?T-6{3I
super(); Q 3WD!Z8y
} cU;Bm}U
w2B)$u
/** ^t0!Dbx3SE
* The constructor using fields .6y+van
* E\iK_'#
* @param page ?P9aXwc
* @param content K^WDA])
*/ %.bDK}
public Result(Page page, List content){ 1_Yx]%g<
this.page = page; C4m+Ta%
this.content = content; r8:r}Qj2w[
} /?.?1-HM
Ca-"3aQkc
/** f2gtz{r
* @return Returns the content. AG(6.
*/ f_k'@e {
publicList getContent(){ `Vvi]>,cg`
return content; ^G4YvS(
} TQR5V\{&%
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/** y|LHnNQ
* @return Returns the page. /^=1]+_!
*/ k*1Lr\1
public Page getPage(){ \M`qaFan5^
return page; +wi=IrRr
} zTng]Mvx
lZk
z\
/** CE"/&I
* @param content .s{"NqRA
* The content to set. x`6MAZ
*/ LOU P
public void setContent(List content){ BlJiHz!
this.content = content; p4T$(]7
} b0~r/M;J
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/** V%-hP~nyBx
* @param page V60L\?a
* The page to set. Q[OwP
*/ .`D'eS6b
publicvoid setPage(Page page){ ItVN,sVJb
this.page = page; mSYjc)z
} M`Y^hDl 6
} Nj9A-*0g6N
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g*$2qKm
12`u[O}\}-
2. 编写业务逻辑接口,并实现它(UserManager, >axeUd+@i
3Gs\Q{O:
UserManagerImpl) 3?o4
java代码: KVZB`c$<t
R3B+vLGX
qO{z{@jo55
/*Created on 2005-7-15*/ ` GF w?G
package com.adt.service; JBY.er`6C
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import net.sf.hibernate.HibernateException; snaAn?I4
"0eX/rY%
import org.flyware.util.page.Page; D!`;v Z\>
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import com.adt.bo.Result; Q}#Je.;
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/** xQsxc
* @author Joa G+dq
*/
*/ sq$v6x sl
publicinterface UserManager { DI\=udN
5dj" UxH
public Result listUser(Page page)throws ]\*^G@HA2
3d}v?q78
HibernateException; NQ{(G8x9
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} H07\z1?.K
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`n&:\Ib
zQ,rw[C"W
1Q@]b_"Xh
java代码: .UPh
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KF(H
>gs
/*Created on 2005-7-15*/ c~<;}ve^z
package com.adt.service.impl; J&8KIOz14Z
-,8LL@_
import java.util.List;
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SAP/jD$5]>
import net.sf.hibernate.HibernateException; N{%7OG
Vk{;g
import org.flyware.util.page.Page; zYzV!s2^
import org.flyware.util.page.PageUtil; 6n]+(=
3U<m\A1
import com.adt.bo.Result; ceUe*}\cr
import com.adt.dao.UserDAO; sS-dHa
import com.adt.exception.ObjectNotFoundException; 9q"kM
import com.adt.service.UserManager; 4l 67B]o
x9YQd69
/** <YvXyIs
* @author Joa E+]}KX:
*/ zud_BOq{f
publicclass UserManagerImpl implements UserManager { Im;%.J
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private UserDAO userDAO; ?[JP[
qS
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/** 8?Zhh.
* @param userDAO The userDAO to set. ]PS`"o,pF$
*/ $INB_/RE
publicvoid setUserDAO(UserDAO userDAO){ 9nR\7!_
this.userDAO = userDAO; .!3e$mhV
} zsp%Cz7T
c!IZLaVAr9
/* (non-Javadoc) A-!e$yz>
* @see com.adt.service.UserManager#listUser GRcPzneiz
>pF* unC;
(org.flyware.util.page.Page) zj7ta[<tr
*/ ~nA k-toJ
public Result listUser(Page page)throws x3y+=aj
Tz1^"tx9
HibernateException, ObjectNotFoundException { i(4<MB1a
int totalRecords = userDAO.getUserCount(); @j\:K<sk
if(totalRecords == 0) :+\0.\K0!
throw new ObjectNotFoundException .OdtM
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yCxYFi
("userNotExist"); B0Df7jr%`>
page = PageUtil.createPage(page, totalRecords); LdZVXp^
List users = userDAO.getUserByPage(page); SA TX_
returnnew Result(page, users); ~P|;Y<?3
} ?~o`mg
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} j4/[Z'5ny
s!IIvF
3-/|G-4k7
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uf/G%/
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 d"XZlEV
t'U=K>7
询,接下来编写UserDAO的代码: eIvZhi
3. UserDAO 和 UserDAOImpl: ;FqmZjm
java代码: +[G9PP6
qHk{5O3
w~@"r#-
/*Created on 2005-7-15*/ sT?{
package com.adt.dao; e"hfeNphz
Uj5-x%~
import java.util.List; h4]^~stI
gWr7^u&q@|
import org.flyware.util.page.Page; 'WW:'[Syn'
@}
Ig*@
import net.sf.hibernate.HibernateException; cQEUHhRg!
Qj^Uz+b
/** cKVFykwM
* @author Joa Z!g6uV+.5
*/ bB$f=W!m%
publicinterface UserDAO extends BaseDAO { l|.}>SfL^u
UyRy>:n
publicList getUserByName(String name)throws lsax.uG5x
?F05BS#)X
HibernateException; 7eCjp
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publicint getUserCount()throws HibernateException; h`6 (Oo|
u
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publicList getUserByPage(Page page)throws )Q=u[ p
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HibernateException; V#Wy`
ce
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} cy^=!EfA
}2]|*?1,
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+~)_
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xeF>"6\
java代码: Zv@qdY<:
`PARZ|
P&Keslk
/*Created on 2005-7-15*/ Ll|-CY $
package com.adt.dao.impl; .?u<|4jE6
iYr)Ao5X
import java.util.List; lrE"phYk
=NY;#Jjn
import org.flyware.util.page.Page; RiTL(Yx
K$Bv4_|x
import net.sf.hibernate.HibernateException; ]he~KO[j<
import net.sf.hibernate.Query; `Wx|
4
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import com.adt.dao.UserDAO; vm! y2
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/** M@T{uo
* @author Joa v-#,@&Uwq
*/ )+L|<6J XA
public class UserDAOImpl extends BaseDAOHibernateImpl Gsh9D
obvE m[x!Z
implements UserDAO { +<Gp >c
MnD}i&k[
/* (non-Javadoc) <{W{
Y\_A>
* @see com.adt.dao.UserDAO#getUserByName $z_yx
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(java.lang.String) ^=x /:0
*/ ;n't:yQW
publicList getUserByName(String name)throws i"V.$|,
)5@P|{FF
HibernateException { ykC3Z<pI.
String querySentence = "FROM user in class E+Bc>xl@m
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com.adt.po.User WHERE user.name=:name"; )1
-<v);
Query query = getSession().createQuery XHA|v^
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(querySentence); S]@;`_?m{
query.setParameter("name", name); @K <Onh`
return query.list(); /Qst :q
} xuUEJ
a&
pEwo}NS*H
/* (non-Javadoc) Bv7FZK3
* @see com.adt.dao.UserDAO#getUserCount() _|\X8o_
*/ K^!#;,0
publicint getUserCount()throws HibernateException { W/UA%We3+L
int count = 0; 0m3hL~0(a
String querySentence = "SELECT count(*) FROM Zv}F?4T~:
brTNwRze
user in class com.adt.po.User"; "" UyfC[
Query query = getSession().createQuery K#k/t"r
-. *E<%
(querySentence); CWeQv9h]X
count = ((Integer)query.iterate().next .'=S1|_(
Sqi9'-%m
()).intValue(); F%V|Aa
return count; Il&FC
} a8TtItN
+Kgl/Wg%
/* (non-Javadoc) 62ru%<x=
* @see com.adt.dao.UserDAO#getUserByPage IN/$b^Um
]?]M5rP
(org.flyware.util.page.Page) Z=8&`
*/ 6-\Mf:%B
publicList getUserByPage(Page page)throws ~+{*KPiD
D zD5n
HibernateException { z9
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String querySentence = "FROM user in class J3y_JoS
uNI&U7_"
com.adt.po.User"; $Z;8@O3
Query query = getSession().createQuery +7%?p"gEY\
P?q HzNGi7
(querySentence); @{b5x>KX
query.setFirstResult(page.getBeginIndex()) v9H
t~\>
.setMaxResults(page.getEveryPage()); B=*0
return query.list(); R'Ue>k
} KAZ<w~55c
:uAL(3pQ
} (^W}uDPCB
>h%>s4W
U~=?I)Ni
2W0nA t
hbYstK;]Z
至此,一个完整的分页程序完成。前台的只需要调用 Mo@{1K/9
hYyIC:PXR
userManager.listUser(page)即可得到一个Page对象和结果集对象 K3vZ42n
=p@2[Uo
的综合体,而传入的参数page对象则可以由前台传入,如果用 n`^jNXE
,JI] Eij^
webwork,甚至可以直接在配置文件中指定。 #8XmOJ"W3k
9wCgJ$te
下面给出一个webwork调用示例: (P?|Bk[
java代码: \X\< +KU
a)W|gx6Y
t8Pf~v
/*Created on 2005-6-17*/ ~hq\XQX
package com.adt.action.user; *
4J!@w
f-#:3k*7S
import java.util.List; PI L)(%X
vFHeGq70j
import org.apache.commons.logging.Log; `=;}I@]zj)
import org.apache.commons.logging.LogFactory; r]LP=K1
import org.flyware.util.page.Page; *-*V>ntvT$
nZ=[6?
import com.adt.bo.Result; >3g`6d
import com.adt.service.UserService; >A{e,&