Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 JJ*0M(GG
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 / *Ou$
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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 U_.n=d ~B
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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 DKf}47y
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。 |~Htj4K/
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分页支持类: z2"2tFK
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java代码: F<H`8*q9
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package com.javaeye.common.util; 8HHgN`_
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import java.util.List; 4Ub?*
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publicclass PaginationSupport { HCfS)`
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publicfinalstaticint PAGESIZE = 30; [)T$91
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privateint pageSize = PAGESIZE; IIYX|;1}X
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privateList items; 3D[:Rf[
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privateint totalCount; WzNG<rG
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privateint[] indexes = newint[0]; D0,oml
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privateint startIndex = 0; eB} sg4
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public PaginationSupport(List items, int OsHkAI
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totalCount){ xKkVSEup
setPageSize(PAGESIZE); YGZAtSf3z
setTotalCount(totalCount); [57V8%
setItems(items); noB}p4
setStartIndex(0); ={wjeRp
} Nys'4kx7
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public PaginationSupport(List items, int e!L sc3@
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totalCount, int startIndex){ 2t
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setPageSize(PAGESIZE); .D M1Knj
setTotalCount(totalCount); AQ_#uxI'oa
setItems(items); XEe+&VQmY
setStartIndex(startIndex); h P6fTZ=Ln
} z!uB&2C{k
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public PaginationSupport(List items, int O!@KM;
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totalCount, int pageSize, int startIndex){ R4K eUn"
setPageSize(pageSize); gIf+.^/m1
setTotalCount(totalCount); ^b/q|(Nu&
setItems(items); S+bWD7
setStartIndex(startIndex); x]jdx#'
} LI5cUCl
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publicList getItems(){ #,|_d>p:
return items; /=O+/)l`
} z2EI"'4\9
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publicvoid setItems(List items){ +T8XX@#
this.items = items; 13NS*%~7[
} u/c~PxC
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publicint getPageSize(){ VIlQzM;%^
return pageSize; .L5T4)
} /`]|_>'
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publicvoid setPageSize(int pageSize){ JKu6+V jO
this.pageSize = pageSize; -uY:2
} 4m g
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publicint getTotalCount(){
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return totalCount; <`VJU2
} ;V(}F!U\z
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publicvoid setTotalCount(int totalCount){ `OpC-Z&
if(totalCount > 0){ YH'.Yj2
this.totalCount = totalCount; _xZb;PbFE
int count = totalCount / yl]Cm?8
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pageSize; UOL%tT
if(totalCount % pageSize > 0) o\V4qekk
count++; ,EJ [I^
indexes = newint[count]; ~a0}
for(int i = 0; i < count; i++){ fw~%^*
indexes = pageSize * QBT-J`Pz
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i; 9g,L1 W*
} {m*J95[
}else{ KcyM2hE7
this.totalCount = 0; LRlk9:QD>
} d4=u`2w
} w"Y55EURB
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publicint[] getIndexes(){ WOTu"Yj
return indexes; -<^Q2]PE;
} (DaP~*c3cC
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publicvoid setIndexes(int[] indexes){ B(T4nH_k
this.indexes = indexes; \kRJUX!s
} |^9ig_k`
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publicint getStartIndex(){ T%vbD*nt.
return startIndex; 9'L0Al~L
} )o(F*v
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publicvoid setStartIndex(int startIndex){ ~w}[
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if(totalCount <= 0) !(AFT!
this.startIndex = 0; Am^O{`r41
elseif(startIndex >= totalCount) s 17gi,"X
this.startIndex = indexes #a>!U'1|
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[indexes.length - 1]; TVh7h`Eg
elseif(startIndex < 0) c15^<6]g
this.startIndex = 0; F[giq1#
else{ %cif0Td
this.startIndex = indexes [ESs?v$
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[startIndex / pageSize]; /XK`v=~(l{
} 'r <BaL
} ">^]^wa08
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publicint getNextIndex(){ C+IE<=%F
int nextIndex = getStartIndex() + Qy,qQA/
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pageSize; H/I`c>Zn
if(nextIndex >= totalCount) 9
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return getStartIndex(); Hjkgy%N
else bo/!u
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return nextIndex; cf3c+.o
} (:muxby%
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publicint getPreviousIndex(){ -KiS6$-
int previousIndex = getStartIndex() - [|Pe'?zkf
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pageSize; i^KYZ4/%
if(previousIndex < 0) 6b)UoJxj
return0; -$ft `Ih
else W"@lFUi
return previousIndex; AWNd(B2o
} 1/BMs0 =
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} G* 6<pp
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抽象业务类 tAi9mm;k
java代码: b(Xg6
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/** WcG&W>
* Created on 2005-7-12 RV(z>XM
*/ PyF4uCn"H
package com.javaeye.common.business; 9F4|T7?
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import java.io.Serializable; ;~;St>?\R\
import java.util.List; pwC/&bu
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import org.hibernate.Criteria; A UV$ S2
import org.hibernate.HibernateException; N|LVLsK
import org.hibernate.Session; N9<eU!4>
import org.hibernate.criterion.DetachedCriteria; z\5Nni/~6D
import org.hibernate.criterion.Projections; /GaR&
import Shd,{Z)-Tg
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org.springframework.orm.hibernate3.HibernateCallback; PEl]HI_H
import [9^e
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org.springframework.orm.hibernate3.support.HibernateDaoS G#v7-&Yl6
#!Fs[A5%
upport; 2[hl^f^%,
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import com.javaeye.common.util.PaginationSupport; m`"s$\fah
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public abstract class AbstractManager extends U?{j
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HibernateDaoSupport { Vba}RF[b
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privateboolean cacheQueries = false; 5ntP{p%>
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privateString queryCacheRegion; 3!L)7Z/
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publicvoid setCacheQueries(boolean ffVYlNQ7L
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cacheQueries){ B!v1gh
this.cacheQueries = cacheQueries; QPEv@laM
} H<yec"
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publicvoid setQueryCacheRegion(String m}(DJ?qP
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queryCacheRegion){ ~Zm(p*\T
this.queryCacheRegion = 2LdV=ifq2S
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queryCacheRegion; Zn//u<D
} KI{u:Lbi
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publicvoid save(finalObject entity){ oSoG&4
getHibernateTemplate().save(entity); Cu]X&l
} SccU@3.X~
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publicvoid persist(finalObject entity){ |D~MS`~qd5
getHibernateTemplate().save(entity); ajAEGD2Zq
} C&T3vM
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publicvoid update(finalObject entity){ ;ORy&H aKl
getHibernateTemplate().update(entity); :Us-^zVr
} +l9avy+P(
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publicvoid delete(finalObject entity){ b/EvcN8 }
getHibernateTemplate().delete(entity); pLU>vQA
} jDoWSYu4tY
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publicObject load(finalClass entity, -*EJj>x
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finalSerializable id){ ZS-9|EA<
return getHibernateTemplate().load -~q]0>
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(entity, id); 8/CGg_C1
} rW^&8E[
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publicObject get(finalClass entity, OL>/FOH:Fx
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finalSerializable id){ X%dOkHarB
return getHibernateTemplate().get Xw%z#6l
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(entity, id); j405G4BVW
} }oG&zw
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publicList findAll(finalClass entity){ oAL-v428
return getHibernateTemplate().find("from {1Qwwhov
(<CLftQKg
" + entity.getName()); 38#(ruv
} ax<0grK
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publicList findByNamedQuery(finalString qfu;X-$4
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namedQuery){ >i~c>+R
return getHibernateTemplate 0KZ 3h|4lP
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().findByNamedQuery(namedQuery); j\a?n4g -
} rLnu\X=h$
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publicList findByNamedQuery(finalString query, q\,H9/.0k
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finalObject parameter){ 2{&" 3dq
return getHibernateTemplate li{_biey}
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().findByNamedQuery(query, parameter); i8{jMe!Sa
} u4"+u"{d
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publicList findByNamedQuery(finalString query, pv T!6+
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finalObject[] parameters){ 84{<]y
return getHibernateTemplate \!PC:+uJ
+)|2$$m
().findByNamedQuery(query, parameters); OjCT%6hy;
} YPM>FDxDB
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publicList find(finalString query){ ]X5*e'
return getHibernateTemplate().find uODsXi{z
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(query); <7p2OPD
} 0Zq"-
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publicList find(finalString query, finalObject YT_kMy>
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parameter){ LDNpEX~
return getHibernateTemplate().find }$o%^"[
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(query, parameter); l>G#+#{
} @@5u{K
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public PaginationSupport findPageByCriteria WULj@ds\~
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(final DetachedCriteria detachedCriteria){ `i{ :mio
return findPageByCriteria ?G{fF
H
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \-B>']:R4
} Ax\Fg
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public PaginationSupport findPageByCriteria 2c~^|@
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(final DetachedCriteria detachedCriteria, finalint #4Z$O(
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startIndex){
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return findPageByCriteria J
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(detachedCriteria, PaginationSupport.PAGESIZE, .UDZW*
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startIndex); $p0s
} $~-j-0
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public PaginationSupport findPageByCriteria 5x: XXj"
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(final DetachedCriteria detachedCriteria, finalint AE$)RhY`
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pageSize, (-#{qkA
finalint startIndex){ 9W8Dp?:
return(PaginationSupport) S\,{qhd
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getHibernateTemplate().execute(new HibernateCallback(){ {/Cd ^CK
publicObject doInHibernate '-x%?Ll
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(Session session)throws HibernateException { .3!4@l\9C
Criteria criteria = c;e,)$)-|
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detachedCriteria.getExecutableCriteria(session); Xnh1pwDhe<
int totalCount = 0eLK9u3<
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((Integer) criteria.setProjection(Projections.rowCount M{H&5 9v
8%"e-chd
()).uniqueResult()).intValue(); J0K"WmW
criteria.setProjection C+k>Ajr
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(null); 9D<HJ(
List items = {\e}43^9N
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criteria.setFirstResult(startIndex).setMaxResults okv7@8U#p
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(pageSize).list(); o i?ak
PaginationSupport ps = rQqtejcfx
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new PaginationSupport(items, totalCount, pageSize, L_~G`Rb3
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startIndex); 3LmHH
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return ps; jDnh/k0{d
} H1]\B:
}, true); yV. P.Q
} 6PH*]#PfoD
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public List findAllByCriteria(final cG?266{g
8vo}
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DetachedCriteria detachedCriteria){ {
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return(List) getHibernateTemplate |`nVr>QF&
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().execute(new HibernateCallback(){
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publicObject doInHibernate -O5m@rwt<
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(Session session)throws HibernateException { eBB
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Criteria criteria = mm 8O
{ SfU!
detachedCriteria.getExecutableCriteria(session); `g=~u{0
return criteria.list(); *pMA
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} #5D+XB T
}, true); DkIFvsLK
} 9E^piLA
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public int getCountByCriteria(final UU/|s>F
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DetachedCriteria detachedCriteria){ ,3j7Y5v
Integer count = (Integer) BP6Shc|C
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getHibernateTemplate().execute(new HibernateCallback(){ |>4 { 4
publicObject doInHibernate \K6J{;# L
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(Session session)throws HibernateException { 9:>K!@
Criteria criteria = s,Swlo7D!
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detachedCriteria.getExecutableCriteria(session); UL%ihWq
return F?B=:8,}
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criteria.setProjection(Projections.rowCount ooQ( bF
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()).uniqueResult(); .yPx'_e
} ZTZE_[
}, true); bRp[N
return count.intValue(); WQx;tX
} KfNXX>'
} %u}sVRJ
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用户在web层构造查询条件detachedCriteria,和可选的 5MJ'/Fy(
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 R{_IrYk
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PaginationSupport的实例ps。 @ni~ij
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ps.getItems()得到已分页好的结果集 Kdm5O@tq
ps.getIndexes()得到分页索引的数组 &u-Bu;G.e
ps.getTotalCount()得到总结果数 k 9rnT)YU
ps.getStartIndex()当前分页索引 $nn5;11@gY
ps.getNextIndex()下一页索引 *q{UipZbx
ps.getPreviousIndex()上一页索引 $Stu-l1e a
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 k#xpY!'7
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 9 NQq=@
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一下代码重构了。 n bk(FD6
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我把原本我的做法也提供出来供大家讨论吧: TzGm562o%
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首先,为了实现分页查询,我封装了一个Page类: c ?XUb[
java代码: .Er/t"Qs;
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/*Created on 2005-4-14*/ ;4$C$r!t
package org.flyware.util.page; J_|x^
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/** (p=GR#
* @author Joa R"`{E,yj
* `gN68:B
*/ N1~$ +
publicclass Page { "|`9{/]
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/** imply if the page has previous page */ \*aLyyy3
privateboolean hasPrePage;
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/** imply if the page has next page */ ^1=|(Z/
privateboolean hasNextPage; +Q31K7G r
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/** the number of every page */ pVS2dwBqE
privateint everyPage; ^]&{"!
9PK-r;2
/** the total page number */ \/'n[3x
privateint totalPage; 5C1Rub)
K"j=_%{
/** the number of current page */ 2-!Mao"^
privateint currentPage; &> .1%x@R
@;D}=$x
/** the begin index of the records by the current :b*`hWnQ
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query */ K/v-P <g
privateint beginIndex; 1Z8Oh_DC
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/** The default constructor */ UMQW#$~C{g
public Page(){ 3}{5
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} N('DIi*or
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/** construct the page by everyPage R(N(@KC
* @param everyPage % W',c u
* */ u%T$XG
public Page(int everyPage){ %yM'
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this.everyPage = everyPage; N 3p 7 0
} Ja=70ZI^6
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/** The whole constructor */ GtJ*&=(
public Page(boolean hasPrePage, boolean hasNextPage, ANQa2swM
)-KE 4/G
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int everyPage, int totalPage, Bi:wP/>v
int currentPage, int beginIndex){ oEoJa:h
this.hasPrePage = hasPrePage; }9udo,RWu
this.hasNextPage = hasNextPage; ?J@qg20z
this.everyPage = everyPage; wU)5Evp[
this.totalPage = totalPage; S{i@=:
this.currentPage = currentPage; bSR+yr'?
this.beginIndex = beginIndex; _JJKbi
} _% 9+U[@
) v5n "W
/** = #2qX>?
* @return ^}/
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* Returns the beginIndex. W$Q)aA7
*/ ,9tbu!Pvq
publicint getBeginIndex(){ %_R|@cyD
return beginIndex; xT?} wF
} @*O{*2
R5&$h$[/
/** ->2wrOH|H
* @param beginIndex %^?3s5PXD
* The beginIndex to set. uj9tr`Zh
*/ <Z:8~:@
publicvoid setBeginIndex(int beginIndex){ pebx#}]p-
this.beginIndex = beginIndex; -C-OG}XjI
} 9#T%bB"J
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/** 1;:t~Y
* @return @23RjoK
* Returns the currentPage. gLSG:7m@
*/ `TD%M`a
publicint getCurrentPage(){ =#Cf5s6qt
return currentPage; h3]@M$Y[
} Q@W|GOH3
%f_OP$;fc
/** UG"6RW @
* @param currentPage "ex~LB
* The currentPage to set. :7Z\3_D/
*/ R(?<97
publicvoid setCurrentPage(int currentPage){ [mf7>M`p]@
this.currentPage = currentPage;
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} _{*$>1q
,KhMzE8_a
/** y }&4HrT&
* @return @Tfwh/UN
* Returns the everyPage. |
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*/ L>~@9a\jO
publicint getEveryPage(){ cbu nq"
return everyPage; vJj:9KcP>h
} by|?g8
9 yW~79n
/** p17|ld`
* @param everyPage tf7v5iG e
* The everyPage to set. <5ft6a2fQ
*/ %eJ\d?nw
publicvoid setEveryPage(int everyPage){ 3r-Vx P 5n
this.everyPage = everyPage; [}p
} _/jUs_W
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/** Z.aLk4QO@
* @return Q k;Kn
* Returns the hasNextPage. *qO]v9 j
*/ i{|lsd(+
publicboolean getHasNextPage(){ %uz|NRB=
return hasNextPage; dI_r:xN
} W7TXI~7
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/** }c35FM,
* @param hasNextPage Z[})40[M
* The hasNextPage to set. T@Ss&eGT2
*/ VA=#0w
publicvoid setHasNextPage(boolean hasNextPage){ M2;%1^
this.hasNextPage = hasNextPage; Esz1uty
} 2;%#C!TG;
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/** y|e2j&m
* @return rb *C-NutE
* Returns the hasPrePage. dXhCyr%"6
*/ @~$F;M=.*
publicboolean getHasPrePage(){ c_qcb7<~.
return hasPrePage; --
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} \'; t*
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/** nIV.9#~&
* @param hasPrePage ;w+:8<mM}a
* The hasPrePage to set. W>}Qer4
*/ #aitESbT
publicvoid setHasPrePage(boolean hasPrePage){ dysX
this.hasPrePage = hasPrePage; BcZEa^^~os
} 42Aje
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bH7q
/** 6K4`;
* @return Returns the totalPage. v:veV. y
* f.b8ZBNj>
*/ IOsXPf9@
publicint getTotalPage(){ uQ:ut(
return totalPage; VD9
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} vx\nr8'k
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/** `d}W;&c
* @param totalPage I" 8d5a}
* The totalPage to set. 6P%<[Z
*/ ilDJwZg#
publicvoid setTotalPage(int totalPage){ < -Hs<T|tW
this.totalPage = totalPage; >vD['XN,
} E6'8Zb
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} TnN^2:cU
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9,S,NvSq
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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 Q7CwQi
6-*~t8
个PageUtil,负责对Page对象进行构造: 457fT |
java代码: tXf}jU}
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:
/*Created on 2005-4-14*/ eZ!yPdgy|
package org.flyware.util.page; f![xn2T
y!7B,
import org.apache.commons.logging.Log; ?-pxte8
import org.apache.commons.logging.LogFactory; P<>[e9|
%'{V%IXQ
/** -!XrwQyk
* @author Joa gf:vb*#Wa
* H{j~ihq7
*/ ?*CRa$_I|
publicclass PageUtil { sTd}cP
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privatestaticfinal Log logger = LogFactory.getLog /QrA8
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(PageUtil.class); JZ %`%rA
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/** vx04h ~
* Use the origin page to create a new page &e%{k@
* @param page @
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* @param totalRecords _n<
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* @return >lA7*nn
*/ ?D1x;i9<
publicstatic Page createPage(Page page, int +DicP"~*
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totalRecords){ xh{mca>?G
return createPage(page.getEveryPage(), aN>U. SB
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page.getCurrentPage(), totalRecords); S#P+B*v
} ^Lsc`<xC
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/** |tG05 +M
* the basic page utils not including exception D4AEZgC F,
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handler nped
* @param everyPage lN);~|IOv7
* @param currentPage PASuf.U$"
* @param totalRecords H!Wis3S3G
* @return page nA>*IU[
*/ p:Iw%eZ:
publicstatic Page createPage(int everyPage, int Bp&6x;MJf
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currentPage, int totalRecords){ 40 Au9o
everyPage = getEveryPage(everyPage); UE"7
currentPage = getCurrentPage(currentPage); ''_,S,.a20
int beginIndex = getBeginIndex(everyPage, Er`TryN|}
.JNcY]V#
currentPage); 0o;k?4aP.c
int totalPage = getTotalPage(everyPage, ]9fS@SHdx
u06tDJ[
totalRecords); xy2\'kS`G
boolean hasNextPage = hasNextPage(currentPage, {V.Wk
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totalPage); MO[c0n%
boolean hasPrePage = hasPrePage(currentPage); /^d. &@*
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returnnew Page(hasPrePage, hasNextPage, s5Pq$<
everyPage, totalPage, b([:,T7
currentPage, g+igxC}2z
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beginIndex); 7`Qde!+C
} >+L7k^[,0
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privatestaticint getEveryPage(int everyPage){ U> W|(Y
return everyPage == 0 ? 10 : everyPage; NK 8<=
n%"
} jz|VF,l
Cm^Ylp
privatestaticint getCurrentPage(int currentPage){ 2>g^4(
return currentPage == 0 ? 1 : currentPage; ]Fxku<z7|
} O97VdNT8
bk.*k~_
privatestaticint getBeginIndex(int everyPage, int w_\nB}_
c2/"KT
currentPage){ j]AekI4I
return(currentPage - 1) * everyPage; ?'Cb-C_
} hMv2"V-X
[Uswf3
privatestaticint getTotalPage(int everyPage, int aUAcRW
D2{L=
totalRecords){ 2v4W6R
int totalPage = 0; SBC~QD>L+
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if(totalRecords % everyPage == 0) >#INEO
totalPage = totalRecords / everyPage; 5~QhX22
else tbg*_ZQO u
totalPage = totalRecords / everyPage + 1 ; 3eWJt\}?B
2H6:np|O
return totalPage; \/n+j!
} 7vw;Egd@@-
]{<saAmJC
privatestaticboolean hasPrePage(int currentPage){ To pHE
return currentPage == 1 ? false : true; w"1x=+
} 7aV$YuL)X~
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privatestaticboolean hasNextPage(int currentPage, UAdz-)$
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int totalPage){ p:Oz<P
return currentPage == totalPage || totalPage == 0',[J
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0 ? false : true; GKCM|Y
}
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hzq5![/sV
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} as(; ]
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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。 Z/gsCYS3F
76_<xUt{
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 N\'TR6_,b
x7HA722w
做法如下: ]W;:|/,c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zz&vfO31J
p3 e|j
的信息,和一个结果集List: %Uf'+!4l`
java代码: _H8*ReFG
Zb"jB$58
0iV;g`%
/*Created on 2005-6-13*/ Yh$fQ:yi\&
package com.adt.bo; drI\iae{^
9)Ly}Kzx
import java.util.List; R#ya,L
TU%bOAKF\
import org.flyware.util.page.Page; "T7>)fbu
zSKKr?{
/** GB=bG%Tb
* @author Joa bJwc1AJgH
*/ `0rRKlb j4
publicclass Result { (n,N8k;
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private Page page; ;
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x)_r@l`$ix
private List content; eVx~n(m!}
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/** IT18v[-G
* The default constructor {yS;NU`2
*/ W+\?~L.
public Result(){ lH6fvz
super(); \E77SO,$
} 0<Q*7aY
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/** BPewc9RxV
* The constructor using fields `;cz;"
* {[P!$
/
* @param page SO_>c+Dw
* @param content xNIGO/uI~
*/ /?P!.!W&
public Result(Page page, List content){ G\ex^&M
this.page = page; Kp&3=e;vn{
this.content = content; 7 >bMzdH
} }LQC.!
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/** j^ nu|
* @return Returns the content. X}W)3v
*/ ?oKL&I@
publicList getContent(){ =?/&u<
return content; Mq'IkSt'
} jT-<IJh!o
CN\=9Rvs
/** F>-}*o
* @return Returns the page. D5L{T+}Oi%
*/ CA*~2|
public Page getPage(){ $3\,h;y
return page; +`}o,z/^
} N2FbrfNFa
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/** T8Na]V5
* @param content K<RqBecB
* The content to set. x0<^<D &Q
*/ x7$ax79ly
public void setContent(List content){ [.&[<!,.
this.content = content; $.8 H>c
} (a#pvEY
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/** 6tm\L
* @param page O{q&]~,
* The page to set. vRr9%zx
*/ V3uXan_
publicvoid setPage(Page page){ B^q<2S;
this.page = page; Z@M6!;y#
} \fi}Q\|C
} <5IQc[3]aP
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0*yJ %
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2. 编写业务逻辑接口,并实现它(UserManager, niWx^gKb$
nzuF]vo
UserManagerImpl) xS+rHC
java代码: ~Z/7pP+
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/*Created on 2005-7-15*/ fp;a5||5
package com.adt.service; bEI!Ja
s
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import net.sf.hibernate.HibernateException; mH\@QdF
BS2?!;,8
import org.flyware.util.page.Page; N!c
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import com.adt.bo.Result; vgThK9{m;
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/** n9]
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* @author Joa P%)b+H{$h
*/ 38Efp$)
publicinterface UserManager { X| <yq
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public Result listUser(Page page)throws !^v\^Fc
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HibernateException; OKPJuV`y6
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} GV6mzD@<
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=x
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java代码: 6N3@!xtpi
*Hunp Y
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/*Created on 2005-7-15*/ GYoseqZM
package com.adt.service.impl; .'lN4x
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import java.util.List; oD0EOT/E
H[nz]s
import net.sf.hibernate.HibernateException; 7zGMkl
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import org.flyware.util.page.Page; O?E6xc<8
import org.flyware.util.page.PageUtil; aU(tu2
H.~bD[gA
import com.adt.bo.Result; r0btC@Hxy
import com.adt.dao.UserDAO; D9o*8h2$
import com.adt.exception.ObjectNotFoundException; :Tb7r6
import com.adt.service.UserManager; _6rKC*Pe1
8*Zvr&B,G
/** 4bI*jEc\[
* @author Joa
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*/ 3cThu43c
publicclass UserManagerImpl implements UserManager { N-QCfDao
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private UserDAO userDAO; PEzia}m
@?a4i
/** W~NYU
* @param userDAO The userDAO to set. }n[Bq#
*/ ,`
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publicvoid setUserDAO(UserDAO userDAO){ U~/ID
this.userDAO = userDAO; VDiOO
} DL4iXULNY
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/* (non-Javadoc) SqqDV)Uih1
* @see com.adt.service.UserManager#listUser J]\^QMX
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(org.flyware.util.page.Page) os**hFPk;1
*/ O`(U/?
public Result listUser(Page page)throws o#}mkE87
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HibernateException, ObjectNotFoundException { }Vl^EAR
int totalRecords = userDAO.getUserCount(); V6*?$o
if(totalRecords == 0) 1b[NgOXY=
throw new ObjectNotFoundException c F=P!2@
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("userNotExist"); KN, 4@4
page = PageUtil.createPage(page, totalRecords); jY+Do:#/wO
List users = userDAO.getUserByPage(page); 4 J8Dh;a`
returnnew Result(page, users); Cuv|6t75'
} a_%>CD${t
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} o9+Q{|r
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}`]]b+_b>@
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 -0DZ::
FG#nap{
询,接下来编写UserDAO的代码: hS_.l}0yf
3. UserDAO 和 UserDAOImpl: iT$d;5_pU
java代码: 8&?p
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/*Created on 2005-7-15*/ )_Iz>)
package com.adt.dao; {aIZFe}B
3'^S3W%
import java.util.List; ?i%nMlcc
b9#m m
import org.flyware.util.page.Page; AY;<q$8j%,
zq=&4afOE
import net.sf.hibernate.HibernateException;
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/** Bac| ;+L~L
* @author Joa T 9MzUV&
*/ UM\}aq=,
publicinterface UserDAO extends BaseDAO { # JFYws
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publicList getUserByName(String name)throws nX 8B;*p6b
g]4yAV<2
HibernateException; M:(&n@e
)f[C[Rd
publicint getUserCount()throws HibernateException;
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@ExLh9
publicList getUserByPage(Page page)throws zzE]M}s
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HibernateException; y($EK(cb
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} G<fS(q
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kwc*is
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java代码: )@,N7Y1h
IywiCMjH
V8T#NJ
/*Created on 2005-7-15*/ S*s:4uf
package com.adt.dao.impl; J@gm@ jLc
K4Y'B
o4
import java.util.List; $E @ouX?
0<3E
import org.flyware.util.page.Page; AHWh}~Yi
X98#QR#m
import net.sf.hibernate.HibernateException; BjB&[5?z
import net.sf.hibernate.Query; "]<w x_!+}
6+?wnp-
import com.adt.dao.UserDAO; G
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/** >~^`5a`$uI
* @author Joa XJ O[[G`
*/ \#2
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public class UserDAOImpl extends BaseDAOHibernateImpl X*)?LxTj
'9"%@AFxZ
implements UserDAO { V07VwVD
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/* (non-Javadoc) P*7S3Td
* @see com.adt.dao.UserDAO#getUserByName dB@FI
#1B}-PGCm
(java.lang.String) Enu!u~1]F
*/ F$[)Bd /"
publicList getUserByName(String name)throws m|lM.]2_
]~'9
HibernateException { HmW=t}!
String querySentence = "FROM user in class brj[c>ID
aj?2jU~Pq
com.adt.po.User WHERE user.name=:name"; 8<Xq=*J+
Query query = getSession().createQuery }a'cm!"
L,WkJe3
(querySentence); )O9f hj)
query.setParameter("name", name); WqR7uiCi
return query.list(); lS#7xh
} X:U=MWc>
tg3zXJ4k_
/* (non-Javadoc) [z^Od
* @see com.adt.dao.UserDAO#getUserCount() x\6];SXX
*/ o>.AdZby
publicint getUserCount()throws HibernateException { 2G
ZF/9}
int count = 0; p%tE v
String querySentence = "SELECT count(*) FROM Jb7iBQ2%
`t%|.=R
user in class com.adt.po.User"; e~3]/BL
Query query = getSession().createQuery iQu^|,tHEM
|^?`Q.|c$
(querySentence); <>VIDE
count = ((Integer)query.iterate().next Qg[heND
b$dBV}0 L
()).intValue(); 8>ESD}(
return count; xC'mPcU8
} t?KUK>>w
::v;)VdX+*
/* (non-Javadoc) Z>X9J(=
* @see com.adt.dao.UserDAO#getUserByPage aXX,Zu^
4{Q$!O>
(org.flyware.util.page.Page) U7jhV,gO4
*/ kp'b>&9r
publicList getUserByPage(Page page)throws F|6
nwvgq
";75 6'>
HibernateException { JR])xPI`
String querySentence = "FROM user in class Kq$:\B)<c
cD5w| rm?i
com.adt.po.User"; ES^NBI j5P
Query query = getSession().createQuery EN)YoVk
KuIkul9^%
(querySentence); E2h(w_l
query.setFirstResult(page.getBeginIndex())
c^rC8E
.setMaxResults(page.getEveryPage()); y:~eU
return query.list(); ,|6Y\L
} kea e.6[
?Y%}(3y
} w8G7Jy
sf
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pi|\0lH6W
cZ6?P`X
至此,一个完整的分页程序完成。前台的只需要调用 NAJ '><2
dv}8YH["
userManager.listUser(page)即可得到一个Page对象和结果集对象 Ti hnSb
|Uc<;> l
的综合体,而传入的参数page对象则可以由前台传入,如果用 X";TZk
_2wAaJvA
webwork,甚至可以直接在配置文件中指定。 tX@0:RX%
]^Sd9ba
下面给出一个webwork调用示例: th5
X?so
java代码: C_6GOpl
5P-K *C&
$Vo/CZW7
/*Created on 2005-6-17*/ 8FAT(f//.
package com.adt.action.user; $$k7_rs
r5D jCV"
import java.util.List; <9=zP/Q
Cw6>^
import org.apache.commons.logging.Log; n>u.3wL
import org.apache.commons.logging.LogFactory; wYZy e^7
import org.flyware.util.page.Page; W/b"a? wE{
UAnB=L,.\
import com.adt.bo.Result; ]\[m=0K
import com.adt.service.UserService; jn.R.}TT
import com.opensymphony.xwork.Action; `)0Rv|?
or?0PEx\
/** t8L<x
* @author Joa _Syre6k
*/ FgXu1-
publicclass ListUser implementsAction{ 2 9&sydu
qXXYF>Z-
privatestaticfinal Log logger = LogFactory.getLog CkmlqqUHC
{
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(ListUser.class); Hlz'a1\:O]
pw0Px
private UserService userService; |Dl*w/n
sjkWz2]S
private Page page; C4&U:y<ju
b7?U8/#'
privateList users; MDMtOfe|
SNQz8(O
/* 59&T