Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $\S;f"IM.
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O]"3o,/]G
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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 Md~%
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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 YVzcV`4w(
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分页支持类: ]bjXbbHd
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java代码: {u3eel
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package com.javaeye.common.util; T7vSp<i/
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import java.util.List; |'w_5?|4
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publicclass PaginationSupport { koiQJdK
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publicfinalstaticint PAGESIZE = 30; N!7r~B
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privateint pageSize = PAGESIZE; ZG=B'4W
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privateList items; ]}4{|& e
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privateint totalCount; udRum7XW3
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privateint[] indexes = newint[0]; aNZJs<3;'D
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privateint startIndex = 0; ?^F*M#%?
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public PaginationSupport(List items, int H+^93
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totalCount){ s0,\[rM
setPageSize(PAGESIZE); *?;<buJb?
setTotalCount(totalCount); OYcf+p"<\
setItems(items); JfJUOaL
setStartIndex(0); +-b:XeHSZ
} ?y.q<F)
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public PaginationSupport(List items, int 6XVr-ef
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totalCount, int startIndex){ Hwr#
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setPageSize(PAGESIZE); 1J}i :i&
setTotalCount(totalCount); )_*<uSl
setItems(items); d2b L_
setStartIndex(startIndex); +UzFHiGy#
} PQla-
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public PaginationSupport(List items, int Yzr RnVr
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totalCount, int pageSize, int startIndex){ Gp=X1 F
setPageSize(pageSize); B;SN}I
setTotalCount(totalCount); y[U/5! `zV
setItems(items); h,|49~^@"
setStartIndex(startIndex); s%tPGjMq
} vmI2o'zi
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publicList getItems(){ MA\^<x_?L}
return items; 71AR)6<R
} ;D Mv?-H
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publicvoid setItems(List items){ =@#[@Ia
this.items = items; Qt+|s&HGt
} ./_o+~\e'
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publicint getPageSize(){ @agW{%R:.
return pageSize; v 4@=>L
} 1<hj3
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publicvoid setPageSize(int pageSize){ . &dh7`l
this.pageSize = pageSize; C4Pi6.wf
} 1WGcv O)<
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publicint getTotalCount(){ &^ECQ
return totalCount; X[L6Av
} ISHNeO8
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publicvoid setTotalCount(int totalCount){ 5):2;h k
if(totalCount > 0){ l_ycYD$ZA
this.totalCount = totalCount; O34'c_ fZ
int count = totalCount / AJ'YkSg
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pageSize; l3Vw?f
if(totalCount % pageSize > 0) 8 *@knkJ
count++; s1,kTde
indexes = newint[count]; "=l<%em
for(int i = 0; i < count; i++){ fo63H'7
indexes = pageSize * TH_Vw,)
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} yZf+*j/a7
}else{ (<ybst6+I
this.totalCount = 0; */gm! :Ym
} DAs&4Y`
} 9Y:JA]U&8
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publicint[] getIndexes(){ iz'#K?PF_
return indexes; } D5*
} qaBjV6loy
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publicvoid setIndexes(int[] indexes){ .r9-^01mG
this.indexes = indexes; :tP:X+?O
} %N\pfZ2\
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publicint getStartIndex(){ 4l! ^"=rh
return startIndex; 3c5=>'^F
} xyO]Evg
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publicvoid setStartIndex(int startIndex){ k0|*8
if(totalCount <= 0) h:QKd!Gq
this.startIndex = 0; M[5zn
elseif(startIndex >= totalCount) <y${Pkrj
this.startIndex = indexes ien >Ou
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[indexes.length - 1]; |CME:;{T
elseif(startIndex < 0) du2q6"
this.startIndex = 0; iqecm]Z0
else{ (5@9j
this.startIndex = indexes 8+Lig
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[startIndex / pageSize]; '>:mEXK}w
} sa\v9
} xwxMVp`|o
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publicint getNextIndex(){ XcJ'w
int nextIndex = getStartIndex() + }Sa2s&[<
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pageSize; J~z;sTR
if(nextIndex >= totalCount) 7)zn[4v7qt
return getStartIndex(); ]Xcqf9k
else <Sn5ME<*
return nextIndex; t0Q/vp*/
} x;NCW
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publicint getPreviousIndex(){ B 95}_q
int previousIndex = getStartIndex() - Ij>x3L\-
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pageSize; i][7S mN
if(previousIndex < 0) [07N<<
return0; xw-x<7
else 'tK5s>gv<
return previousIndex; se](hu~w
} 2-821Sf#h
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} >LxYP7M
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抽象业务类 11}fPWK
java代码: ToIvyeFr
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/** }fw;{&s{z
* Created on 2005-7-12 GW$(E*4q
*/ ouKID_'
package com.javaeye.common.business; HxJKS*H;
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import java.io.Serializable; -X(%K6{
import java.util.List; EzY?=<Y(
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import org.hibernate.Criteria; b7>^w<ki
import org.hibernate.HibernateException; E)|_7x<u
import org.hibernate.Session; <^VZ4$j
import org.hibernate.criterion.DetachedCriteria; HBYqqEO
import org.hibernate.criterion.Projections; "HFS5Bj'
import +M%i3A
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org.springframework.orm.hibernate3.HibernateCallback; ,-Fhb~u
import i> Ssp
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org.springframework.orm.hibernate3.support.HibernateDaoS }*l V
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upport; >jAr9Blz]
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import com.javaeye.common.util.PaginationSupport; N m-{$U
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public abstract class AbstractManager extends z^9Yoqog
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HibernateDaoSupport { th8f
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privateboolean cacheQueries = false; Y4`MgP8t
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privateString queryCacheRegion; ay#cW.,
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publicvoid setCacheQueries(boolean /zn|?Y[
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cacheQueries){ ^a|$z$spf
this.cacheQueries = cacheQueries; >L/Rf8j &
} !o &+
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publicvoid setQueryCacheRegion(String O!='U!X@P
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queryCacheRegion){ Ay<'Z6`
this.queryCacheRegion = m`
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queryCacheRegion; 9Qp39(l:
} O
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publicvoid save(finalObject entity){ ?_ [xpK()
getHibernateTemplate().save(entity); zLXmjrC
} %JDG aG'
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publicvoid persist(finalObject entity){ -yeQQ4b
getHibernateTemplate().save(entity); :7p0JGd
} TCp!4-~,
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publicvoid update(finalObject entity){ "s2?cQv{#
getHibernateTemplate().update(entity); c"t1E-Nsk
} 4vTO # F
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publicvoid delete(finalObject entity){ c\UVMyE
getHibernateTemplate().delete(entity); &oiX/UaY
} @Fqh]1t
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publicObject load(finalClass entity, nL@
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finalSerializable id){ 'P}"ZHW
return getHibernateTemplate().load +V1EqC*
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(entity, id); m_~
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} XEV-D9n
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publicObject get(finalClass entity, W5(t+$L.
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finalSerializable id){ FQB)rxP
return getHibernateTemplate().get BDxrS q,H
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(entity, id); ;6t>!2I>C
} PC/fb-J
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publicList findAll(finalClass entity){ k);z}`7
return getHibernateTemplate().find("from
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" + entity.getName()); &T]+g8 ''
} (p`'Okw
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publicList findByNamedQuery(finalString zy4AFW
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namedQuery){ IGT~@);
return getHibernateTemplate (}O)pqZ>
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().findByNamedQuery(namedQuery); >h<eEv/
} 0~A<AF*t
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publicList findByNamedQuery(finalString query, # j*$ `W;
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finalObject parameter){ [Z,AquCU(
return getHibernateTemplate r\vB-nJ
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().findByNamedQuery(query, parameter); qyUcjc%[
} p*!@z|F>U
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publicList findByNamedQuery(finalString query, MTb}um.($
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finalObject[] parameters){ n)} J<
return getHibernateTemplate 8Nxf2i5
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().findByNamedQuery(query, parameters); CSc*UX+
} _@;2h`q ?
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publicList find(finalString query){ '15j$q
return getHibernateTemplate().find BQSA;;n]
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(query); yNc>s/
} <Nvw
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publicList find(finalString query, finalObject Sn.I
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parameter){ E{T\51V]%
return getHibernateTemplate().find GWjKZ1p
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(query, parameter); XZcsx
} N$pwTyk
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public PaginationSupport findPageByCriteria rZu_"bcJ
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(final DetachedCriteria detachedCriteria){ H; TmG<S
return findPageByCriteria 34YYw@?}Y
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ou2H~3^PL
} z"}k\B-5
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public PaginationSupport findPageByCriteria X]cB`?vR
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(final DetachedCriteria detachedCriteria, finalint ol!o8M%Q
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startIndex){ kjaz{&P
return findPageByCriteria J}jK_
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(detachedCriteria, PaginationSupport.PAGESIZE, 3mWo`l
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startIndex); _QvyFKAM
} t8i"f L
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public PaginationSupport findPageByCriteria *Q!b%DIa$
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(final DetachedCriteria detachedCriteria, finalint [.6>%G1C
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pageSize,
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finalint startIndex){ F1M@$S,
return(PaginationSupport) "oz@w'rG
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getHibernateTemplate().execute(new HibernateCallback(){ [2i+f<
publicObject doInHibernate `Z|sp
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(Session session)throws HibernateException { rO]C`bg
Criteria criteria = 1Dt"Rcn"4
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detachedCriteria.getExecutableCriteria(session); $k'f)E
int totalCount = 3Xd+>'H
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((Integer) criteria.setProjection(Projections.rowCount V]q{N-Iq
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()).uniqueResult()).intValue(); )V@qH]
criteria.setProjection }S#.Pw%
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(null); Vaha--QB
List items = 3BY/&'oX
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criteria.setFirstResult(startIndex).setMaxResults v[Q)cqj/
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(pageSize).list(); S<Q1
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PaginationSupport ps = <(f4#BP
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new PaginationSupport(items, totalCount, pageSize, jQb=N%5s
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startIndex); So`xd
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return ps; @b>]q$)(}
} 5&}icS
}, true); FblGFm"P
} 46XB6z01
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public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ 7PQedZ<\
return(List) getHibernateTemplate @=;6:akz`
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().execute(new HibernateCallback(){ W!X#:UM)
publicObject doInHibernate fx;5j;
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(Session session)throws HibernateException { 8U;!1!+
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Criteria criteria = {;p/V\
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detachedCriteria.getExecutableCriteria(session); (XW#,=rYk
return criteria.list(); spl*[ d
} 9&d BL0
}, true); `Mjm/9+18
} SQ.4IWT(hR
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public int getCountByCriteria(final 0(i`~g5
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DetachedCriteria detachedCriteria){ I*
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Integer count = (Integer) 61mQJHl.
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getHibernateTemplate().execute(new HibernateCallback(){ PH7L#H^
publicObject doInHibernate gIRCJ=e[b
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(Session session)throws HibernateException { +?.,pq n<=
Criteria criteria = F;b|A`M
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detachedCriteria.getExecutableCriteria(session); qnA:[H;F
return #-@{ rgH
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criteria.setProjection(Projections.rowCount |hdh4P$+|
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()).uniqueResult(); t%TZu>(1O
} Wt`D
}, true); }!d}febk_
return count.intValue(); xO.7cSqgw
} $(NfHIX
} ~Fx[YPO,
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用户在web层构造查询条件detachedCriteria,和可选的 p/:5bvA
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 .Gv~e!a8
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PaginationSupport的实例ps。 (8*lLZ
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ps.getItems()得到已分页好的结果集 T2->
ps.getIndexes()得到分页索引的数组 asF-mf;D
ps.getTotalCount()得到总结果数 <G&v
ps.getStartIndex()当前分页索引 aQG#bh [
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 B@=Yj_s
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 c[YjGx
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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 J{Ay(
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一下代码重构了。 [x)e6p)
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我把原本我的做法也提供出来供大家讨论吧: 4tC_W!?$t
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首先,为了实现分页查询,我封装了一个Page类: K@i*Nl
java代码: BmM,vllO
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/*Created on 2005-4-14*/ j*zK"n
package org.flyware.util.page; M'HOw)U
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/** 35>}$1?-6
* @author Joa |.
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* "h2Ny#
*/ |]q=D1/A
publicclass Page { saT9%?4-
%C)JmaQ{9
/** imply if the page has previous page */ yRznP)
privateboolean hasPrePage;
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/** imply if the page has next page */ _R<HC
privateboolean hasNextPage; K$.zO4
moR]{2Cd{
/** the number of every page */ vh HMxOZ;
privateint everyPage; n1t(ns|
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/** the total page number */ hG@ys5
privateint totalPage; `[KhG)Y7t
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/** the number of current page */ e!yw"Cf*
privateint currentPage; [1*/lt|+p
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/** the begin index of the records by the current .#@D n(
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query */ (2li:1j
privateint beginIndex; nADd,|xD3
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/** The default constructor */ sV<4^n7
public Page(){ wb[(_@eZ
k)s 7Ev*
} 78)^vvn5~
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/** construct the page by everyPage Q8x{V_Pot
* @param everyPage a%!XLyq
* */ ^{s0d+@{
public Page(int everyPage){ ~Z2eQx
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this.everyPage = everyPage; PR?clg=z
} :#}`uR,D/
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/** The whole constructor */ {*U:Wm<
public Page(boolean hasPrePage, boolean hasNextPage, cnthtv+(~
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int everyPage, int totalPage, }L!`K"^O&
int currentPage, int beginIndex){ _zh5KP[{
this.hasPrePage = hasPrePage; ku?_/-ko]
this.hasNextPage = hasNextPage; |esjhf}H>v
this.everyPage = everyPage; G 7]wg>*
this.totalPage = totalPage; Bx-,"Z \
this.currentPage = currentPage; zfb _ )
this.beginIndex = beginIndex; c0&'rxi(B
} v|@n8ED|@K
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/** ]5fM?: <l
* @return ts<dUO
* Returns the beginIndex. 6ZpcT&yL
*/ )|R9mW=k9P
publicint getBeginIndex(){ ~C/KA6H
return beginIndex; od1omYsR
} 1`lFF_stkP
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/** o2 d~
* @param beginIndex suFOc
* The beginIndex to set. #@^w>D6W
*/ j7#GqVS'
publicvoid setBeginIndex(int beginIndex){ i@5%d!J
this.beginIndex = beginIndex; /\cu!yiX
} oh~
vo!
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/** ;Ia1L{472m
* @return HFuaoS+b*
* Returns the currentPage. MuV0;K\
*/ SRN9(LN
publicint getCurrentPage(){ rs Uw(K^
return currentPage; @z)tC@
} ""3m!qn#
^YJA\d@
/** WWW#s gM%
* @param currentPage { $/Fk6qr
* The currentPage to set. >JPJ%~y
*/ }.UI&UZ-
publicvoid setCurrentPage(int currentPage){ O6,"#BX
this.currentPage = currentPage; Hu8atlpo
} F.pHL)37
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/** z-G7Y#
* @return Z,!Xxv;4
* Returns the everyPage. yI.H4Dl<
*/ A;-z#R#V5
publicint getEveryPage(){ q'F_j"
return everyPage; KV}U{s+U8
} 19 wqDIE0
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/** nX\]i~
* @param everyPage @gSFvb bc
* The everyPage to set. 2~WFLD
*/ Pgw%SMEp
publicvoid setEveryPage(int everyPage){ RyOT[J
this.everyPage = everyPage; b2X'AHK S
} P^3m:bE]
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/** -*hb^MvP
* @return R``VQ
* Returns the hasNextPage. 9LO.8Jy
*/ %C`'>,t>
publicboolean getHasNextPage(){ O
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return hasNextPage; !N8)C@=
} zLw h6^?Y
207 O["Y
/** j(6$7+2qN
* @param hasNextPage _SIs19"lR
* The hasNextPage to set. fE%[j?[
*/ 0uIV6LI
publicvoid setHasNextPage(boolean hasNextPage){ 2r}uE\GN
this.hasNextPage = hasNextPage; i\Pr3
7
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} ^UvK~5tBV
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/** 6+$d
* @return zz 'dg-F
* Returns the hasPrePage. vN,}aV2nq
*/ OKZam ik~
publicboolean getHasPrePage(){ 5<O61Lgx
return hasPrePage; HM@}!6/s
} qSoBj&6y
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/** o%+A<Ri
* @param hasPrePage K rr?`n
* The hasPrePage to set. n`m_S
*/ c7g.|R
publicvoid setHasPrePage(boolean hasPrePage){ Xh0wWU*
this.hasPrePage = hasPrePage; Lk`k>Nn)
} &=z1$ih>2\
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/** >2lAy:B5
* @return Returns the totalPage. ~w1{zxs
* fsrg2:kQ
*/ +(<n |~
publicint getTotalPage(){ <RoX| zJw
return totalPage; 20/P M9
} i|c`M/) h:
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v3*
/** JMirz~%ib
* @param totalPage pY)j0tdd
* The totalPage to set. jA-5X?!In
*/ hmBnV
publicvoid setTotalPage(int totalPage){ \za5:?[xB
this.totalPage = totalPage; ?Rt1CDu
} x0u?*5-t
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} &ppE|[{
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+ q
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 mEB2RLCM
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个PageUtil,负责对Page对象进行构造: Et}C`vZ+Ve
java代码: lPRdwg-
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/*Created on 2005-4-14*/ ;.nP%jD
package org.flyware.util.page; FVsu8z u
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import org.apache.commons.logging.Log; *Z]5!$UpC
import org.apache.commons.logging.LogFactory; mJ8{lXq3!
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/** bmj8WZ
* @author Joa /<(*/P,>
* y:g7'+c
*/ PPwxk;
publicclass PageUtil { ?418*tXd
C.yY8?|
privatestaticfinal Log logger = LogFactory.getLog 9UeVvH
+CnyK(V
(PageUtil.class); |D;_:x9
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/** $6:XsrV\a
* Use the origin page to create a new page wJ80};!
* @param page v Q-ixh
* @param totalRecords 93Mdp9v+i
* @return ^%n124
*/ n_""M:X H
publicstatic Page createPage(Page page, int !lQ#sL`
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$
totalRecords){ `e'G.@
return createPage(page.getEveryPage(), .k# N7[q=
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page.getCurrentPage(), totalRecords); 6}VUD
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} oupJJDpP
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/** hAV2F#
* the basic page utils not including exception c;c:Ea5
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handler <@u0.-]
* @param everyPage Sk8%(JD7
* @param currentPage -W|*fKN`3
* @param totalRecords %B#hb<7}
* @return page Xtci0eS#V
*/ <A#5v\{.;~
publicstatic Page createPage(int everyPage, int IXGW2z;
[ 3$.*
currentPage, int totalRecords){ tO?21?AD D
everyPage = getEveryPage(everyPage); reJ"r<2
currentPage = getCurrentPage(currentPage); 25x cD1*
int beginIndex = getBeginIndex(everyPage, wn
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currentPage); :fxWz%t
int totalPage = getTotalPage(everyPage, mWNR( ()v
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totalRecords); 0Vf)Rw1%I
boolean hasNextPage = hasNextPage(currentPage, B }6Kd
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totalPage); .D+RLO z
boolean hasPrePage = hasPrePage(currentPage); 7<^'DOs
n`P`yb\f$
returnnew Page(hasPrePage, hasNextPage, T1l&B
everyPage, totalPage, 5B}3GBA
currentPage, (FM4 ^#6
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beginIndex); Q2*/`L}m\
} N1PECLS?
O
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privatestaticint getEveryPage(int everyPage){ .j:i&j(
return everyPage == 0 ? 10 : everyPage; joe9.{
} 2*+3RrJ
JYPxd~T/-
privatestaticint getCurrentPage(int currentPage){ $np=eT)
return currentPage == 0 ? 1 : currentPage; 'KSa8;:=C
} .FuA;:@%\
a lrt*V|=
privatestaticint getBeginIndex(int everyPage, int CNut{4
Was'A+GZ
currentPage){ aIQOs
return(currentPage - 1) * everyPage; ;U
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} e[s5N:IUd3
Z*9L'd"D|
privatestaticint getTotalPage(int everyPage, int f7Yz>To
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totalRecords){ pP3U,n
int totalPage = 0; iu+3,]7Fm
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if(totalRecords % everyPage == 0) p:B
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totalPage = totalRecords / everyPage; ~u!gUJ:
else &(g|="T
totalPage = totalRecords / everyPage + 1 ; PJCnud F
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return totalPage; :ztyxJv1
} CQ<8P86gt
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privatestaticboolean hasPrePage(int currentPage){ 7UnzIe
return currentPage == 1 ? false : true; =qw&dwIQ
} S9J5(lYv~N
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privatestaticboolean hasNextPage(int currentPage, QeL{Wa-2F
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6\
int totalPage){ eO'xkm
return currentPage == totalPage || totalPage == ovz#
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0 ? false : true; prUHjS
} sW?B7o?
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} y<|)'(
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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。 X($6IL6m
[7RheXO<
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 gGmxx,i
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做法如下: )=Zsv40O
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 o_O+u%y
V/ +Jc(N
的信息,和一个结果集List: Evkt_vvf
java代码: rCE;'? Y
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/*Created on 2005-6-13*/ Q<yAT(w
package com.adt.bo; @89I#t6A.
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import java.util.List; :c=v}
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import org.flyware.util.page.Page; /~*Cp9F"]
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/** .uKx>YB}
* @author Joa 7WP%J-
*/ xor TL8
publicclass Result { T/5"}P`
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private Page page; H<Hrwy~
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private List content; LEK/mCL
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/** 5>P7]?U.]
* The default constructor YDFCGA
*/ 61Bhm:O5W
public Result(){ d&u7]<yDA
super(); ZBJ3 VK
} -w ~(3(
Q&PB]D{
/** {i>Jfl]G}
* The constructor using fields $/paEn"
* ~.6|dw\p!
* @param page 7]s%rya
* @param content !}5*?k
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*/ ,1
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public Result(Page page, List content){ 5B{k\H;
this.page = page; -\Z `z}D
this.content = content; /EU; ?O
} .=XD)>$
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/** {a@>6)
* @return Returns the content. #Qd'+M
*/ k"
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publicList getContent(){ !| xZ6KV
return content; 4LsHs
} s}ADk-7
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/** ue6d~8&
* @return Returns the page. VNj@5s
*/ ]'k[u
public Page getPage(){ C(o.Cy6
return page; 8%ik853`
} b+@D_E-RJ
IqUp4}
/** RqLNp?V%
* @param content 8QF2^*RZ7z
* The content to set. *QH[,F`I
*/ 8bOT*^b$H
public void setContent(List content){ h$ Da&$uyI
this.content = content; >zmzK{A=
} v"RiPHLT
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/** Jq
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* @param page 0^#DNq*NQ
* The page to set. p7C!G1+z
*/ CCqT tp
publicvoid setPage(Page page){ WeC(w+}p
this.page = page; &g0g]G21*I
} xo Gb
} yN\e{;z`
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2. 编写业务逻辑接口,并实现它(UserManager, [AR>?6G-
K\&o2lo]
UserManagerImpl) 1b3(
java代码: iF9_b
1h=D4yN
z(H?VfJo
/*Created on 2005-7-15*/ _ 08];M|
package com.adt.service; 2a `J%A
l>&sIX
import net.sf.hibernate.HibernateException; .Xd0
Q=1h
8!zbF<W9
import org.flyware.util.page.Page; IgM
v =^U
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!/PQ"
import com.adt.bo.Result; -$YJfQE6G
XmWlv{T+
/** S|K}k:v8
* @author Joa A#DR9Eq
*/ %0XvJF)s
publicinterface UserManager { S LGW:
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public Result listUser(Page page)throws 6OB" ,
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HibernateException; vM4<d>
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} >85zQ
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;%zC@a~{
oT&m4I
gyu6YD8L
java代码: }c|U X
ZW
Y=2Un).&
JsQ6l%9
/*Created on 2005-7-15*/ kX2d7yQZz
package com.adt.service.impl; l,d, T
6RK\}@^=K
import java.util.List; "!Lkp2\
:a3xvN-l
import net.sf.hibernate.HibernateException; ctI{^f:
#C*&R>IvY
import org.flyware.util.page.Page; Eg8i _s~:
import org.flyware.util.page.PageUtil; P5?<_x0v4b
AyVrk
8G
import com.adt.bo.Result; !wh&>3~
import com.adt.dao.UserDAO; 'fY9a(Xt.
import com.adt.exception.ObjectNotFoundException; HI!4
import com.adt.service.UserManager; 9B/1*+ M
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/** _x % 1 F
* @author Joa *Km7U-BG
*/ w> 979g
publicclass UserManagerImpl implements UserManager { '*R%^RK
4%_M27bu[
private UserDAO userDAO; R^8{bP
y=H@6$2EQ
/** '*!L!VJ
* @param userDAO The userDAO to set. IOEM[zhb$
*/ ;/sHWI
f+Z
publicvoid setUserDAO(UserDAO userDAO){ Cs1>bpY*R6
this.userDAO = userDAO; =+oZtP-+o
} ai^|N.!
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/* (non-Javadoc) W`L!N&fB
* @see com.adt.service.UserManager#listUser 4~|<`vqN
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9P)
(org.flyware.util.page.Page) cm@;*
*/ Vb)zZ^va+
public Result listUser(Page page)throws : F9|&q-W,
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HibernateException, ObjectNotFoundException { 6 hiC?2b{x
int totalRecords = userDAO.getUserCount(); h$fe -G#
if(totalRecords == 0) u%2KwRQ
throw new ObjectNotFoundException P(ZQDTbM
:
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("userNotExist"); .
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page = PageUtil.createPage(page, totalRecords); (3%t+aqq
List users = userDAO.getUserByPage(page); u$\a3yi
returnnew Result(page, users); "JT;gaEm
} n?QZFeI`
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} i_l+:/+G+
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flnVYQe
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fL6e?\Pw
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ?[TW<Yx
8^ #mvHah
询,接下来编写UserDAO的代码: j_Nm87i]
3. UserDAO 和 UserDAOImpl: n1J]p#nCa.
java代码: AH d-
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/*Created on 2005-7-15*/ nSS=%,?
package com.adt.dao; V4K'R2t
wda';@y5(
import java.util.List; u"+}I,'L
m5-9yQ=.
import org.flyware.util.page.Page; ]gP5f @`
>. DC!QV
import net.sf.hibernate.HibernateException; PT]GJ<K/
PT_KXk
/** CL9yEy"V
* @author Joa jw>hk
*/ vsMmCd)7U
publicinterface UserDAO extends BaseDAO { Pe$6s:|NS
4gZ&^y'
publicList getUserByName(String name)throws f
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HibernateException; <kc#thL
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publicint getUserCount()throws HibernateException; .6.^G
;=~Xr"(/z
publicList getUserByPage(Page page)throws k1}hIAk3u
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HibernateException; 9- )qZ
@*O?6>
} yoS? s
u, kU$
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java代码: ]<trA$ 0
ls|LCQPx
82:Wvp6
/*Created on 2005-7-15*/ x` /)g(
package com.adt.dao.impl; +U8Bln
V3s L;
import java.util.List; zx%X~U
Vfs$VY2.
import org.flyware.util.page.Page; !:0v{ZQ
^[q /Mw
import net.sf.hibernate.HibernateException; S~yR5cb
import net.sf.hibernate.Query; RFfIF]~3
r`M6!}oa
import com.adt.dao.UserDAO; @WOM#Kc
vq'k|_Qi=
/** =/9^,
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* @author Joa q]c5MlJXF
*/ k$"d^*R
public class UserDAOImpl extends BaseDAOHibernateImpl LN^f1/b*
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implements UserDAO { w1^QD^KnH
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/* (non-Javadoc) }nrXxfu
* @see com.adt.dao.UserDAO#getUserByName {aOkV::
=1hr2R(V
(java.lang.String) q mQfLz7&x
*/ }DjYGMrTB
publicList getUserByName(String name)throws 0^l%j 8/
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HibernateException { }iiHr|l3
String querySentence = "FROM user in class S2^>6/[xM
{qpi?oY
com.adt.po.User WHERE user.name=:name"; ZxHJ<2oD
Query query = getSession().createQuery w#y2_
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(querySentence); o( G"k
query.setParameter("name", name); < n?=|g
return query.list(); cy3Td28,
} EbK0j?
&t}?2>:
/* (non-Javadoc) W`)<vGn=Y
* @see com.adt.dao.UserDAO#getUserCount() t~p
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*/ 6 "gj!/e
publicint getUserCount()throws HibernateException { Akk
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int count = 0; tw K^I6@
String querySentence = "SELECT count(*) FROM ^twivNB
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user in class com.adt.po.User"; /b[2lTC-e
Query query = getSession().createQuery lP_db&
7 &%^>PU7
(querySentence); :8f[|XR4\N
count = ((Integer)query.iterate().next ~}ovuf=%
m,MSMw1p
()).intValue(); dQ:cYNm
return count; h #.N3o
} [c&