Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6cT~irP
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %g@3S!lK
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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 m?% H<4X
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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 nk|N.%E
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分页支持类:
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java代码: ])j|<W/
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package com.javaeye.common.util; A~GtK\=;
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import java.util.List; x D=qU
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publicclass PaginationSupport { _Z66[T+M
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publicfinalstaticint PAGESIZE = 30; 26#Jhb E+
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privateint pageSize = PAGESIZE; &*]{"^
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privateList items; m{$tO;c/Q
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privateint totalCount; :&0yf;>v
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privateint[] indexes = newint[0]; eMl]td rI
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privateint startIndex = 0; y.*=Ww+
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public PaginationSupport(List items, int jFNs=D&(
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totalCount){ "^
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setPageSize(PAGESIZE); *iRm`)zC(
setTotalCount(totalCount); Ce5w0&VlS
setItems(items); hi3sOK*r;<
setStartIndex(0); O? Gl4_y
} <[y$D=n
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public PaginationSupport(List items, int &Ky u@Tt
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totalCount, int startIndex){ bxhg*A
setPageSize(PAGESIZE); yLgKS8b
setTotalCount(totalCount); 2}Z4a\YX
setItems(items); ',H$zA?i
setStartIndex(startIndex); NrJ_6sjF0g
} Y7kb1UG
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public PaginationSupport(List items, int Y=:KM~2hv
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totalCount, int pageSize, int startIndex){ /y9J)lx
setPageSize(pageSize); 4Ay`rG
setTotalCount(totalCount); j.;
setItems(items); % L >#
setStartIndex(startIndex); KM6N'x ^z
} dm,}Nbc91(
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publicList getItems(){ .A*VLF*m
return items; oGJ*Rn)Z
} 5qd_>UHp
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publicvoid setItems(List items){ KZrMf77=
this.items = items; '6o`^u>
} hEv=T'*,K)
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publicint getPageSize(){ o=-Vt,2{
return pageSize; b\?7?g
} gv#c~cX]
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publicvoid setPageSize(int pageSize){ #
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this.pageSize = pageSize; mWli}j#
} ~&DB!6*
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publicint getTotalCount(){ bB:r]*_
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return totalCount; 3`fJzS% O
} SE;Tujwhqi
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publicvoid setTotalCount(int totalCount){ #*Yi4Cn<
if(totalCount > 0){ Y^f94s:2S
this.totalCount = totalCount; $!|8g`Tm
int count = totalCount / jD '
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pageSize; 7b&JX'`Mb
if(totalCount % pageSize > 0) #+K
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count++; )D["M$ZA^
indexes = newint[count]; cBLR#Yu;O5
for(int i = 0; i < count; i++){ AXl!cgi
indexes = pageSize * j{{~Z M
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i; ^)f{q)to
} ;-KAUgL2
}else{ aNE9LAms
this.totalCount = 0; PPoI>J
} G$;]
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} GOy=p3mQ
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publicint[] getIndexes(){ #`jE%ONC
return indexes; 9Fy\t{ks
}
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publicvoid setIndexes(int[] indexes){ hWD !
this.indexes = indexes; 1R=)17'O
} TL},Unq
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publicint getStartIndex(){ ~L %Pz0Gg
return startIndex; M}Nb|V09
} 9wO/?
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publicvoid setStartIndex(int startIndex){ 7FmbV/&c
if(totalCount <= 0) 1Pk mg%+
this.startIndex = 0; iNod</+"K
elseif(startIndex >= totalCount) .FIt.XPzv
this.startIndex = indexes omM&{ }8 g
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[indexes.length - 1]; f._l105.
elseif(startIndex < 0) uiktdZ/f
this.startIndex = 0; vk
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else{ u0m5JD0/
this.startIndex = indexes $%7I:
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[startIndex / pageSize]; M{`/f@z(
} :s'o~
} q} ]'Q
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publicint getNextIndex(){ J DLTOLG
int nextIndex = getStartIndex() + &w+;N5}3
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pageSize; (k%GY<
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if(nextIndex >= totalCount) W8w3~
return getStartIndex(); 01U
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else bTZ>@~$
return nextIndex; 9$Ig~W)
} 0:Ar|to$m
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publicint getPreviousIndex(){ LnP3z5d(
int previousIndex = getStartIndex() - U'tE^W
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pageSize; F-_%>KJS
if(previousIndex < 0) ;wJ~ha C
return0; $o]r]#B+
else CY34X2F
return previousIndex; ^vJ"-{
} W7H&R,
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} yJ%t^ X_
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抽象业务类 k@#5$Ejc2
java代码: EE+`i%
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/** $:Rn;
* Created on 2005-7-12 FY$fV"s
*/ gX[|;IZ0o
package com.javaeye.common.business; 4|`Yz%'
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import java.io.Serializable; h@=7R
import java.util.List; puOC60zI
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import org.hibernate.Criteria; 2@vJ
import org.hibernate.HibernateException; n5|l|#c$N
import org.hibernate.Session; 4t04}vp
import org.hibernate.criterion.DetachedCriteria; `>s7M.|X
import org.hibernate.criterion.Projections; M :V2a<!c
import ]<1HM"D
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org.springframework.orm.hibernate3.HibernateCallback; c! @F
import U#bl=%bF
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org.springframework.orm.hibernate3.support.HibernateDaoS dm6~
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upport; Frk c O
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import com.javaeye.common.util.PaginationSupport; X 7=fX~s
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public abstract class AbstractManager extends J1bA2+5.*e
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HibernateDaoSupport { u_PuqRcs
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privateboolean cacheQueries = false; P.djd$#
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privateString queryCacheRegion; +iy7e6P
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publicvoid setCacheQueries(boolean $$hv`HE^l
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cacheQueries){ hrbo:8SL
this.cacheQueries = cacheQueries; Ow3P-UzU3
} p,F^0OU2}:
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publicvoid setQueryCacheRegion(String (zG.aaz*C
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queryCacheRegion){ H6gU?9%
this.queryCacheRegion = . V$ps-t
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queryCacheRegion; ZsZcQj6G,
} YzAFC11,
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publicvoid save(finalObject entity){ ?vgH"W~3>
getHibernateTemplate().save(entity); NBjeHtT
} @b2`R3}9R
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publicvoid persist(finalObject entity){ 9I`Y-D
getHibernateTemplate().save(entity); *:_P8G;
} Q/ZkW
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publicvoid update(finalObject entity){ n-o3
getHibernateTemplate().update(entity); y:d{jG^
} ;gMgj$mI
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publicvoid delete(finalObject entity){ :~zv t
getHibernateTemplate().delete(entity); o%[U
} Z)pz,
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publicObject load(finalClass entity, F2 ~%zNe
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finalSerializable id){ 1f#mHt:(
return getHibernateTemplate().load fr[3:2g-_
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(entity, id); R^*K6Ad
} dRI^@n
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publicObject get(finalClass entity, zP!J/}z
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finalSerializable id){ kS :\Oz\
return getHibernateTemplate().get %+-C3\'
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(entity, id); Jq
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} ZDx@^P y
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publicList findAll(finalClass entity){ YE}s
return getHibernateTemplate().find("from 4 =Gph
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" + entity.getName()); l&$$w!n0w
} T[?6[,.
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publicList findByNamedQuery(finalString \}_Yd8
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namedQuery){ tNIlzR-
return getHibernateTemplate kforu!C
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().findByNamedQuery(namedQuery); Xm1[V&
} cK`"lxO
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publicList findByNamedQuery(finalString query, AoaN22
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finalObject parameter){ 7=XL!:P
return getHibernateTemplate %7hB&[ 5
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().findByNamedQuery(query, parameter); WO</Mw
} LN2D
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publicList findByNamedQuery(finalString query, |=a}iU8
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finalObject[] parameters){ BxK^?b[E8
return getHibernateTemplate lb*8G
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().findByNamedQuery(query, parameters); _-~`03 `!
} Zm
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publicList find(finalString query){ wJ<Oo@snm
return getHibernateTemplate().find h*B|fy4K9U
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(query); sZ<9A Xk-E
} ,Gk}"w
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publicList find(finalString query, finalObject `Y=WMNy
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parameter){ &w8)* T
return getHibernateTemplate().find p&-'|'![l
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(query, parameter); f:B>zp;N
} ;Lm=dd@S:
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public PaginationSupport findPageByCriteria X^9d/}uTa
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(final DetachedCriteria detachedCriteria){ ;a{ :%t
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Z?Hs@j
} G~7 i@Zs
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public PaginationSupport findPageByCriteria 6 15s5ZA
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(final DetachedCriteria detachedCriteria, finalint ?ULo&P[
:!a2]-D}
startIndex){ '})0!g<Y
return findPageByCriteria P|tNL}2`;
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(detachedCriteria, PaginationSupport.PAGESIZE, ENF"c$R
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startIndex); :u8(^]N
} 7!y5
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public PaginationSupport findPageByCriteria z7M_1%DEx
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(final DetachedCriteria detachedCriteria, finalint 2Qp Hvsl_
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pageSize, f
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finalint startIndex){ h:zK(;
return(PaginationSupport) [%Bf<
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getHibernateTemplate().execute(new HibernateCallback(){ !o=U19)
publicObject doInHibernate Io4(f
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(Session session)throws HibernateException { ofYlR|
Criteria criteria = rNjn~c
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detachedCriteria.getExecutableCriteria(session); ^EG\iO2X
int totalCount = 7@lS.w\#-
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((Integer) criteria.setProjection(Projections.rowCount :c9U>1`g&
W>VP'vn}
()).uniqueResult()).intValue(); :1XtvH
criteria.setProjection /xGmg`g<#
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(null); ^<e@uNGg
List items = ~_s?k3cd
'TH15r@
criteria.setFirstResult(startIndex).setMaxResults 6hZ@;Q=b
[gy*`@w
(pageSize).list(); T,xPSN2A*
PaginationSupport ps = *_E|@y
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new PaginationSupport(items, totalCount, pageSize, -C(b,F%%
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startIndex); XNQAi (!GS
return ps; :=%0Mb:
} o?1;<gs
}, true); Xc"&0v%;#
} [aI]y=v
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public List findAllByCriteria(final B+^(ktZp@
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DetachedCriteria detachedCriteria){ !RyO\>:q
return(List) getHibernateTemplate \#o2\!@`
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().execute(new HibernateCallback(){ fwK}/0%
publicObject doInHibernate [=B$5%A
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(Session session)throws HibernateException { 2I*;A5$N1
Criteria criteria = fDG0BNLY
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detachedCriteria.getExecutableCriteria(session); HB
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return criteria.list(); l;y7]DO
} >.dWjb6t
}, true); 8
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} '*\|;l#1
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public int getCountByCriteria(final TuW %zF/
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DetachedCriteria detachedCriteria){ ~QvqG{bFB
Integer count = (Integer) h?bb/T+'
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getHibernateTemplate().execute(new HibernateCallback(){ o9cM{ya/>
publicObject doInHibernate 5M9 I,
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(Session session)throws HibernateException { JaB<EL-9r2
Criteria criteria = Gmf B
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detachedCriteria.getExecutableCriteria(session); Us+pc^A
return z<B8mB
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criteria.setProjection(Projections.rowCount F(t=!k,4\
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()).uniqueResult(); JK.ZdY%
} 3;%5Yu
}, true); ^"J8r W6[
return count.intValue(); QWMdn
} \GHiLs,!
} =gcM%=*'
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用户在web层构造查询条件detachedCriteria,和可选的 P-ri=E}>
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 6xD#?
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PaginationSupport的实例ps。 *
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ps.getItems()得到已分页好的结果集 =0;^(/1Mc
ps.getIndexes()得到分页索引的数组 F<!)4>2@
ps.getTotalCount()得到总结果数 /4xki_}
ps.getStartIndex()当前分页索引 'uq#ai[5I
ps.getNextIndex()下一页索引 4.IU!.Uo
ps.getPreviousIndex()上一页索引 Bdj%hyW
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 C-iK$/U
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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 :O(^w}sle
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一下代码重构了。 {J^lX/D
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我把原本我的做法也提供出来供大家讨论吧: c+2FC@q{l
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首先,为了实现分页查询,我封装了一个Page类: :]J Ye*
java代码: ?(R]9.5S
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/*Created on 2005-4-14*/ .l@xsJn
package org.flyware.util.page; _Gu-
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/** g55`A`5%C
* @author Joa h[PYP5{L
* }fKSqB]T-
*/
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publicclass Page { $^@ )
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/** imply if the page has previous page */ QcgfBsv96
privateboolean hasPrePage; !E T~KL!
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/** imply if the page has next page */ K# Jk _"W
privateboolean hasNextPage; F{UP;"8'
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/** the number of every page */ d9q(xZ5
privateint everyPage; :H c0b=
5|1T}Z#;
/** the total page number */ /tUy3myJ
privateint totalPage; i\dc>C ;
3\Xbmq8}
/** the number of current page */ 0Q^Ikiv
privateint currentPage; CxfRVL`7
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/** the begin index of the records by the current Aj0Tfdxy
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query */ VZ\B<i
privateint beginIndex; A,`8#-AX
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/** The default constructor */ n/h,Lr)Z
public Page(){ %?m$`9yU
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} {Lm~r+
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/** construct the page by everyPage 8HP6+c%
* @param everyPage sq;s]@~
* */ Ybn`3
public Page(int everyPage){ N&M~0iw
this.everyPage = everyPage; Yh>]-SCw
} 1CHeufQ
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/** The whole constructor */ K3=3~uY
public Page(boolean hasPrePage, boolean hasNextPage, 6qp%$>$Vt;
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ldp%{"ZZ
int everyPage, int totalPage, Hbpqyl%O>
int currentPage, int beginIndex){ /"B?1?qc,=
this.hasPrePage = hasPrePage; 6qaulwV4t
this.hasNextPage = hasNextPage; ndeebXw*
this.everyPage = everyPage; 46 PoM
this.totalPage = totalPage; 0A( +ZMd
this.currentPage = currentPage; ="g*\s?r
this.beginIndex = beginIndex; =dFv/F/RW
} W]nSR RWco
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/** $ mI0Bk
* @return vPD]hs
* Returns the beginIndex. |M+<m">E
*/ rs~wv('
publicint getBeginIndex(){ $5*WLG&AK
return beginIndex; Z"AQp _
} rSJ9v:
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/** 9[^gAR
* @param beginIndex |gU(s
* The beginIndex to set. `+uhy,
*/ ma((2My'H
publicvoid setBeginIndex(int beginIndex){ nG;8:f`
this.beginIndex = beginIndex; xQ@^$_
} |JVk&8
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/** 1u6^z
* @return _-#'j2
* Returns the currentPage. ka3u&3"
*/ vo#UtN:q
publicint getCurrentPage(){ +mp@b942*
return currentPage; <-u8~N@43W
} ^Y
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/** 1[yq0^\]M[
* @param currentPage ('hEr~&
* The currentPage to set. E~_]Lfs)
*/ E8~}PQW:I
publicvoid setCurrentPage(int currentPage){ 8f3vjK'
this.currentPage = currentPage; YWxc-fPZ
} UNkCL4N
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/** lHhUC16>
* @return z
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* Returns the everyPage.
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*/ EeF'&zE-
publicint getEveryPage(){ )kkhJI*v
return everyPage; R@`y>X GNJ
} .Fa4shNV
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/** 3fh8$A
* @param everyPage "1HRLci
* The everyPage to set. wV^V]c ?U
*/ :M6+p'`j
publicvoid setEveryPage(int everyPage){ uI DuGrt
this.everyPage = everyPage; Xt'sQ}
} ~R@Nd~L
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/** NwZ@#D#[ Y
* @return (bh95X
* Returns the hasNextPage. pf_mf.
*/
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publicboolean getHasNextPage(){ npNB{J[
return hasNextPage; /*c\qXA5
} as>L[jyG/
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/** HVC>9_:]
* @param hasNextPage PK4iuU`vh
* The hasNextPage to set. ]TyisaT
*/ oun;rMq
publicvoid setHasNextPage(boolean hasNextPage){ \R3H+W
this.hasNextPage = hasNextPage; 78/N
} *>+,(1Fz
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/** C|?o*fQ
* @return {U_$&f9s
* Returns the hasPrePage. R?p00
*/ {4-[r#R<M
publicboolean getHasPrePage(){ Yp:KI7
return hasPrePage; q.()z(M7
} v= N!SaK{
w&x!,yd;
/** Bdu&V*0g
* @param hasPrePage ZPD[5)~
* The hasPrePage to set. Cj?L@%"
*/ RJ$7XCY%`*
publicvoid setHasPrePage(boolean hasPrePage){ FSRj4e1y1
this.hasPrePage = hasPrePage; Kk{<@v)
} uSR~@Lj ~
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/** 5T:i9h
* @return Returns the totalPage. &c*^VL\
* u@4V7;L
*/ P(K>=O
publicint getTotalPage(){ ,yTjU{<"
return totalPage; <fs2fTUeqF
} s\P2Bp_{
2^^=iU=!<|
/** d`/tE?Gw
* @param totalPage G7CG~:3h+
* The totalPage to set. ]$,UPR/3
*/ UAyC.$!
publicvoid setTotalPage(int totalPage){ m{7(PHpw
this.totalPage = totalPage; Ogp"u b 8
} E~a3r]V/
YLVPAODY
} Y9`5G%
A|@_}h"WG
d` [HT``
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 +d%L\^?F
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个PageUtil,负责对Page对象进行构造: H`geS
java代码: V$uk6#
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/*Created on 2005-4-14*/ A?@@*$&
package org.flyware.util.page; &EpAg@9!
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import org.apache.commons.logging.Log; ,do58i
K
import org.apache.commons.logging.LogFactory; HyR!O>
8dlw-Q'S
/** @e'5E^
* @author Joa RAp=s
* /P
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*/ )<xypDQ
publicclass PageUtil { &< !Ufa&
":nQgV\9
privatestaticfinal Log logger = LogFactory.getLog $*W6A/%O
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(PageUtil.class); _fwb!T}$
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/** <Tot|R;
* Use the origin page to create a new page G\a8B#hg
* @param page ,<Q~b%(3
* @param totalRecords @l0|*lo%
* @return .T*GN|@$!
*/ 5IbJ
publicstatic Page createPage(Page page, int UQ.7>Ug+8s
8O"U 0
totalRecords){ .E@|D6$D
return createPage(page.getEveryPage(), 3bNIZ#`|MB
VG>vn`x>a
page.getCurrentPage(), totalRecords); Z,.G%"i3C
} ?r2 #.W
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/** 7jJbo]&
* the basic page utils not including exception \))=gu)I
vhb)2n
handler x{&w?ng
* @param everyPage w2xG_q
* @param currentPage leCVK.
* @param totalRecords ov\HsTeZ
* @return page o5n^!gi4
*/ v-! u\
publicstatic Page createPage(int everyPage, int c c
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currentPage, int totalRecords){ W<<9y
everyPage = getEveryPage(everyPage); ~RD+.A
currentPage = getCurrentPage(currentPage); aSP4a+\*
int beginIndex = getBeginIndex(everyPage, uZi.HG{<)
&,.Y9;
b
currentPage); Ei2%DMN7)
int totalPage = getTotalPage(everyPage, O,.!2wVrN
I_q~*/<h
totalRecords); ')N{wSM9Ft
boolean hasNextPage = hasNextPage(currentPage, A$WZF/x
Bu]t*$
totalPage); LA[g(i 7
boolean hasPrePage = hasPrePage(currentPage); jp+_@S>
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returnnew Page(hasPrePage, hasNextPage, dr<<! q /
everyPage, totalPage, i7LJ&g/)
currentPage, cUO<.
-<#!DjV6(
beginIndex); hwqbi "o
} =KT7nl
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privatestaticint getEveryPage(int everyPage){ .6~`Ubr}E
return everyPage == 0 ? 10 : everyPage; **>/}.%?K
} /xJqJ_70X
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privatestaticint getCurrentPage(int currentPage){ R3X{:1{j
return currentPage == 0 ? 1 : currentPage; {w
<+_++
} pZZf[p^s|
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privatestaticint getBeginIndex(int everyPage, int .O0O-VD+a
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currentPage){ 4m-I5!=O
return(currentPage - 1) * everyPage; 8by@iQ
} Y$-3v.
9,]5v+
privatestaticint getTotalPage(int everyPage, int xE-7P|2
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totalRecords){ \VSATL:]
int totalPage = 0; >b.^kc
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if(totalRecords % everyPage == 0) 4eH.9t
totalPage = totalRecords / everyPage; ai*b:Q
else Z"s|]K "
totalPage = totalRecords / everyPage + 1 ; _e!F~V.
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return totalPage; *xR
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} m%#`y\]I
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privatestaticboolean hasPrePage(int currentPage){ +([!A6:
return currentPage == 1 ? false : true; yGpz,X4x
} y]e> E
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privatestaticboolean hasNextPage(int currentPage, !SsHAE|
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int totalPage){ y }08~L?2
return currentPage == totalPage || totalPage == 0D~ C
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0 ? false : true; FP"$tt (
} c6Q(Ygc
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} 23DJV);g8
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Vga-@
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面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 (ozb%a#B
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做法如下: [t0rfl{.
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /b,TpuM^
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的信息,和一个结果集List: iwY'4Z
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java代码: YW;
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/*Created on 2005-6-13*/ &GWkq>
package com.adt.bo; iz"3\{aN
(!?K7<Jv
import java.util.List; )yxT+g2!
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import org.flyware.util.page.Page; `&$B3)Eb
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/** qI3NkVA'C
* @author Joa Z$ KV&.=+
*/ @\Js8[wS9@
publicclass Result { +K6szGP
#NRh\Wj|
private Page page; `^UK
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private List content; '7Ig.K&
}{],GHCjQ
/** >E"9*:.^a
* The default constructor u2sR.%2U<
*/ rU#li0
>
public Result(){ mxqG-*ch-
super(); ?n'OF pd
} %kU'hzLg
PoD^`()FR{
/** '=cKU0
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* The constructor using fields `EMi0hm&H
* *i<\iMoW
* @param page S-Ai3)t6
* @param content I+,SZ]n
*/ $EBb"+Y'T
public Result(Page page, List content){ rj H`
this.page = page; So4nJ><p
this.content = content; s'_,:R\VM>
} m s~8QL
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/** et$uP
* @return Returns the content. qSiWnN8D
t
*/ =ak7ldA=2
publicList getContent(){ 9XV^z*E(J
return content; IjZ@U%g@;
} >xd<YwXZ
t<b 3K-
/** ?~2Bi^W5
* @return Returns the page. !0fI"3P@r
*/ x,Y5U+]E
public Page getPage(){ h[=nx^
return page; 6f]r Q9
} yBn_Kd
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/** x0Bw{>Q
* @param content ,86K
* The content to set. d#T?Q_3b
*/ [BXyi
public void setContent(List content){ uu}-"/<~7
this.content = content; wRVD_?
} 30 7fBa
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/** \{PNw F?
* @param page <d@pmh
* The page to set. {j6g@Vd6lx
*/ -i_En^Fi
publicvoid setPage(Page page){ IL2r9x%
this.page = page;
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} AQ@v>wr}
} NfF~dK|
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2. 编写业务逻辑接口,并实现它(UserManager, %ejeyc
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UserManagerImpl) R [9w
java代码: ex phe+b
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/*Created on 2005-7-15*/ %3,xaVN
package com.adt.service; ?~)Ak`=
0>Fqx{!heq
import net.sf.hibernate.HibernateException; /2h][zrZ[.
G?[-cNdk
import org.flyware.util.page.Page; BW71 s
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import com.adt.bo.Result; $Sb@zLi)
;c)! @GoA
/** ;E's4jWq
* @author Joa _0]QS4a][c
*/ uL>:tb
publicinterface UserManager { eycV@|6u*
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public Result listUser(Page page)throws 8vJdf9pB*
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HibernateException; L<)Z> @fR
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} "/y|VTV"
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c
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java代码: RHXvee55
1"$R 3@s;
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/*Created on 2005-7-15*/ ;z0"Ox=7
package com.adt.service.impl; oeGS
YOKR//|3
import java.util.List; uRGB/ju^E
,TJ/3_ lH
import net.sf.hibernate.HibernateException; =kO@ Gk?
=phiD&=
import org.flyware.util.page.Page; `5<1EGJsD
import org.flyware.util.page.PageUtil; H PTHF
"GLYyC
import com.adt.bo.Result; \^m.dIPdO
import com.adt.dao.UserDAO; LJ
l1v
import com.adt.exception.ObjectNotFoundException; =~$U^IsWA
import com.adt.service.UserManager; /h-6CR
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/** (uT^Nn9L=
* @author Joa 4ac1m,Jlt
*/ FpC~1Nau
publicclass UserManagerImpl implements UserManager { k -]xSKG
zf7rF}
private UserDAO userDAO; y&3TQ]f\
%/md"S
/** kdd7Xbw-
* @param userDAO The userDAO to set. )(.%QSA\C
*/ X}?ESjZJ
publicvoid setUserDAO(UserDAO userDAO){ (NM6micc
this.userDAO = userDAO; <>&89E%j'
} c&A]pLn+x
z0;9SZ9
/* (non-Javadoc) s+N^PX3
* @see com.adt.service.UserManager#listUser }8
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(org.flyware.util.page.Page) :Lc3a$qtx5
*/ F_ _H(}d
public Result listUser(Page page)throws mf~Lzp
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HibernateException, ObjectNotFoundException { -sx-7LKi
int totalRecords = userDAO.getUserCount(); VlV)$z_
if(totalRecords == 0) excrXx
throw new ObjectNotFoundException :SQLfOQ
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("userNotExist"); w0$R`MOR+
page = PageUtil.createPage(page, totalRecords); w@2~`<Hk'"
List users = userDAO.getUserByPage(page); tNYJQ
returnnew Result(page, users); j^rYFS
w:Q
} F;X"3F.!
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} 0tSA|->(
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 CR.bMF}
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询,接下来编写UserDAO的代码:
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3. UserDAO 和 UserDAOImpl: $xQ"PJ2
java代码:
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:"y0oCu7`W
/*Created on 2005-7-15*/ yI lV[_
package com.adt.dao; F1E.\l
GPMrs)J*!
import java.util.List; 2h5tBEOX.s
_,t&C7Yf;
import org.flyware.util.page.Page; BjwMb&a;
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import net.sf.hibernate.HibernateException; TJE%
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/** Wf_CR(
* @author Joa |}%(6<
*/ v?FhG
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publicinterface UserDAO extends BaseDAO { m&,bC)}
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publicList getUserByName(String name)throws m\1VF\
!W0P`i<
HibernateException; !+5C{Hs2
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publicint getUserCount()throws HibernateException; 8g-P_[>
^P]?3U\nj
publicList getUserByPage(Page page)throws r+SEw ;
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HibernateException; bx;yHIRb
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} `:V}1ioX5
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java代码: ,I/2.Q})[
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ou
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+}kO;\
/*Created on 2005-7-15*/ OTnu{<.a
package com.adt.dao.impl; %3ou^mcj
7s0)3HR}
import java.util.List; z7|
s%&
{qJHL;mP:8
import org.flyware.util.page.Page; mJSK; @w<O
@Q/x&BV
import net.sf.hibernate.HibernateException; G`9cd\^
import net.sf.hibernate.Query; Gv!BB=ir(
#4Dn@Gqh.Y
import com.adt.dao.UserDAO; |if~i;VKL
Y]hV-_2+Do
/** <Z2(qZ^Z
* @author Joa 1 ,#{X3
*/ jB5>y&+
public class UserDAOImpl extends BaseDAOHibernateImpl I93 ~8wQ
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implements UserDAO { BhOXXa{B
@^'G&%j
/* (non-Javadoc) V h
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* @see com.adt.dao.UserDAO#getUserByName .WBI%ci
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(java.lang.String) j2< !z;2
*/ 5{8x*PSl
publicList getUserByName(String name)throws av'd%LZP
mrK,Ql
HibernateException { -q'xC: m
String querySentence = "FROM user in class x:!C(Ep)
SPfD2%jjC
com.adt.po.User WHERE user.name=:name"; Uzan7A
Query query = getSession().createQuery /'R UA
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(querySentence); nYI/&B{p
query.setParameter("name", name); oq=?i%'>
return query.list(); 9`)w@-~~
} +9F^F>mu
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/* (non-Javadoc) om XBnzT
* @see com.adt.dao.UserDAO#getUserCount() )j{WeG7L
*/ %bCcsdK
publicint getUserCount()throws HibernateException { %KbBH:z05
int count = 0; t-.2+6"\
String querySentence = "SELECT count(*) FROM qf_hb
*37LN
user in class com.adt.po.User"; "bHtf_
Query query = getSession().createQuery ~AEqfIx*^&
+^/Nil
(querySentence); H.jLGe>
count = ((Integer)query.iterate().next :5TXA
0ClX
()).intValue(); #)W8.
return count; [z
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} n@G:e-m{A
\e`6=Q%
/* (non-Javadoc) Rel(bA-[N
* @see com.adt.dao.UserDAO#getUserByPage -&q