Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 @QEVl
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 l #Tm`br
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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 >;Bhl|r~z
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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 h0`)=
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。 2;3q](d
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分页支持类: `u-}E9{
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java代码: `i}\k
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package com.javaeye.common.util; (]JJ?aAF
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import java.util.List; &&JMw6
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publicclass PaginationSupport { ^a]:GPc
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publicfinalstaticint PAGESIZE = 30; zAH+{4lC+
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privateint pageSize = PAGESIZE; -vMP{,
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privateList items; |^=`ln!
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privateint totalCount; 67e1Y@Xu
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privateint[] indexes = newint[0]; XDn$=`2
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privateint startIndex = 0; k";;Snk
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public PaginationSupport(List items, int 6};Sn/8
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totalCount){ O&)Y3 O1
setPageSize(PAGESIZE); v4&*iT
setTotalCount(totalCount); f; 22viE
setItems(items); NEN br$,G
setStartIndex(0); r4-r
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} fF9vV. }
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public PaginationSupport(List items, int bZ389dSn
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totalCount, int startIndex){ ]t,ppFC#
setPageSize(PAGESIZE); <%!@cE+y
setTotalCount(totalCount); $FAl9
setItems(items); ,e;(\t:
setStartIndex(startIndex); shi#K<gVC
} n>@(gDq
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public PaginationSupport(List items, int FNUue
8\[6z0+;
totalCount, int pageSize, int startIndex){ k`N)-`O7
setPageSize(pageSize); 4Fnr8 r8W
setTotalCount(totalCount); FuD$jsEw
setItems(items); I|p(8R!
setStartIndex(startIndex); <$UY{"?
} UCl,sn
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publicList getItems(){ _/KN98+
return items; l9-(ofY*J
} xL mo?Y*
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publicvoid setItems(List items){ E*CY/F I_
this.items = items; :imp~~L;
} 0"ZRJl<)[I
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publicint getPageSize(){ h'wI/Z_'
return pageSize; b,I$.&BD
} ]A'E61t<n
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publicvoid setPageSize(int pageSize){ mio\}SA
this.pageSize = pageSize; }VyDX14j
} ]mYY1%H8M
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publicint getTotalCount(){ +Ge-!&.;A
return totalCount; @q|I$'K]x
} V,lz}&3L
}O8$?7j(
publicvoid setTotalCount(int totalCount){ c\7~_w2
if(totalCount > 0){ u>d,6
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this.totalCount = totalCount; |LWG7
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int count = totalCount / 06L/i,
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pageSize; 81`-xVd
if(totalCount % pageSize > 0) tvavI9
count++; ~Sh8. ++}
indexes = newint[count]; Eqnc("m)
for(int i = 0; i < count; i++){ Q/L:0ovR
indexes = pageSize * e0qU2
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i; fpu^
} .r $d
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}else{ 6o!+E@V
b
this.totalCount = 0; %,1bh
} Y2HF
} 0escp~\Z
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publicint[] getIndexes(){ -ich N/U]s
return indexes; E:!?A@Fy
} Z2!O)8
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publicvoid setIndexes(int[] indexes){ 5Ay\s:hb[u
this.indexes = indexes; AQ7w5}g+V
} aOIE9wO
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publicint getStartIndex(){ ===M/}r
return startIndex; .0}]/%al
} {d|e@`"T
Db3#;
publicvoid setStartIndex(int startIndex){ "Y-_83
if(totalCount <= 0) H$^IT#
this.startIndex = 0; w7+3?'L
elseif(startIndex >= totalCount) .?|pv}V
this.startIndex = indexes +`'=K ;{U
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[indexes.length - 1];
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elseif(startIndex < 0) 9=YX9nP
this.startIndex = 0; l3[2b
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else{ <#HQU<
this.startIndex = indexes }M*yE]LL;Z
}04EM
[startIndex / pageSize]; '~{bq'7`m
} Jga;nrU
} v!~tX*q
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publicint getNextIndex(){ Q#M@!&
int nextIndex = getStartIndex() + $S Kax#[
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pageSize; oU"!"t
if(nextIndex >= totalCount) 0[E}[{t`
return getStartIndex(); ~$w9L998+
else :Q]P=-Y8
return nextIndex; jTHgh>n
} xs?Ska,N
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publicint getPreviousIndex(){ ~[a6
int previousIndex = getStartIndex() - b}<?& @
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pageSize; w&F.LiX^
if(previousIndex < 0) I.dS-)Y
return0; D[i?T3i
else 5TynAiSD_>
return previousIndex; :[\M|iAo
} )wqG^yv
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} t nvCtuaR
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抽象业务类 ^K3Bn
java代码: Lqa|9|!
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/** aWS_z6[t#6
* Created on 2005-7-12 ^7l+ Ofb3
*/ %^KNY ;E
package com.javaeye.common.business; "rVf{
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import java.io.Serializable; !FA[
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import java.util.List; r}nz )=\Cj
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import org.hibernate.Criteria; 4ux^K:z
import org.hibernate.HibernateException; GtLnh~)
import org.hibernate.Session; SX1w5+p$C
import org.hibernate.criterion.DetachedCriteria; \DMZ M
import org.hibernate.criterion.Projections; IRG -H!FV
import .dPy<6E
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org.springframework.orm.hibernate3.HibernateCallback; LS%;ZKJ
import ~{cG"
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org.springframework.orm.hibernate3.support.HibernateDaoS PN"SBsc*j-
9.>he+
upport; hMnJH_siY
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import com.javaeye.common.util.PaginationSupport; Qv
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public abstract class AbstractManager extends
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HibernateDaoSupport { /NB;eV?
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privateboolean cacheQueries = false; AQgagE^
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privateString queryCacheRegion; \O=t5yS
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publicvoid setCacheQueries(boolean qr'P0+|~5
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cacheQueries){ M/evZ?uis
this.cacheQueries = cacheQueries; +Z/aB*aVa^
} PzH#tG&.j
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publicvoid setQueryCacheRegion(String D:#e;K
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queryCacheRegion){ cr>"LAi
this.queryCacheRegion = v%8S:3
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queryCacheRegion; \9%RY]TK3
} [DSD[[
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publicvoid save(finalObject entity){ V1 O]L66
getHibernateTemplate().save(entity); !8}x6
} `kM:5f+>W
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publicvoid persist(finalObject entity){ vN$j@h .
getHibernateTemplate().save(entity); 9 #)&
} ~T:L0||.%9
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publicvoid update(finalObject entity){ 't#E-+o
getHibernateTemplate().update(entity); "!z9UiA
} eG08Xt|lc
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publicvoid delete(finalObject entity){ +&qj`hA-b
getHibernateTemplate().delete(entity); [*z`p;n2D
} dZ{yNh.]
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publicObject load(finalClass entity, woyeKOr
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finalSerializable id){ *c'hmAs
return getHibernateTemplate().load e!p?~70
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(entity, id); FWl'='5L
} 'G8.)eTA'
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publicObject get(finalClass entity, <p\iB'y
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finalSerializable id){ sFa5#w*>
return getHibernateTemplate().get o btXtqew
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(entity, id); ,-.a! a
} @ !m+s~~]h
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publicList findAll(finalClass entity){ r0fEW9wL
return getHibernateTemplate().find("from KQ2jeJ/pj
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" + entity.getName());
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} Ln@n6*%(/
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publicList findByNamedQuery(finalString .wJv_
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namedQuery){ ?h7(,39^>
return getHibernateTemplate *\T
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().findByNamedQuery(namedQuery); '
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} iz5WWn^
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publicList findByNamedQuery(finalString query, GEQ3r'B|
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finalObject parameter){ g1B[RSWv
return getHibernateTemplate n2(@uT&>
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().findByNamedQuery(query, parameter); U6
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} \\9$1yg
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publicList findByNamedQuery(finalString query, flzHZH
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finalObject[] parameters){ 3 F ke#t
return getHibernateTemplate WC
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().findByNamedQuery(query, parameters); ">hOD'PG
} @ZTsl ?
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publicList find(finalString query){ <Zn-P
return getHibernateTemplate().find $2lPUQZ<5
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(query); ]v,>!~8r
} 2!E@Gbhm5
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publicList find(finalString query, finalObject K6X}d,g
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parameter){ l\%LT{$e
return getHibernateTemplate().find 8fX<,*#I
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(query, parameter); Gn7P` t*.
} kjVJ!R\
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public PaginationSupport findPageByCriteria ]|PDsb"e
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(final DetachedCriteria detachedCriteria){ #FQkwX'g
return findPageByCriteria ;R
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(detachedCriteria, PaginationSupport.PAGESIZE, 0);
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} {} gr\
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public PaginationSupport findPageByCriteria &)y$XsSMW
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(final DetachedCriteria detachedCriteria, finalint M7JQw/,xs
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startIndex){ gvLzE&V}
return findPageByCriteria 3j2#'Jf|:
okv`+VeA
(detachedCriteria, PaginationSupport.PAGESIZE, aF
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startIndex); -4IHs=`;I
} mtunD;_Dek
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public PaginationSupport findPageByCriteria N(W;\>P
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(final DetachedCriteria detachedCriteria, finalint @V>BG8Y
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pageSize, Zl4X,9Wt
finalint startIndex){ ZJ
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return(PaginationSupport) |2t1m 6\j
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getHibernateTemplate().execute(new HibernateCallback(){ a?dUJt
publicObject doInHibernate $2gX!)
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(Session session)throws HibernateException { + <4gJoI
Criteria criteria = ?Xq"Q^o4#e
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detachedCriteria.getExecutableCriteria(session); 7kDqgod^A
int totalCount = N3rq8Rk
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((Integer) criteria.setProjection(Projections.rowCount )oU%++cdo
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()).uniqueResult()).intValue(); mN&B|KWU
criteria.setProjection 5z~O3QX
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(null); 5HqvSfq>?
List items = #q
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criteria.setFirstResult(startIndex).setMaxResults FMNT0
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(pageSize).list(); m*f"Y"B.1I
PaginationSupport ps = C4H$w:bVk
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new PaginationSupport(items, totalCount, pageSize, ,%X"Caz
089 <B& <
startIndex); dMlJ2\]u
return ps; q*'-G]tH=
} \'9(zb vz9
}, true); j' }4ZwEh
} pt_]&3\e
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public List findAllByCriteria(final Xf%vfAf
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DetachedCriteria detachedCriteria){ Tf{lH9ca$
return(List) getHibernateTemplate O/b1^
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().execute(new HibernateCallback(){ 1/tyne=m
publicObject doInHibernate K0'= O
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(Session session)throws HibernateException { nJ2910"<
Criteria criteria = q5G`N>"V
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detachedCriteria.getExecutableCriteria(session); &ev#C%Nu
return criteria.list(); %%+@s
} ;;}}uW=
}, true); 49tJ+J- N
} Txa
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public int getCountByCriteria(final OIY
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DetachedCriteria detachedCriteria){ R+5yyk\
Integer count = (Integer) k[a5D/b
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getHibernateTemplate().execute(new HibernateCallback(){ 3U9leY'2N
publicObject doInHibernate B,4
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(Session session)throws HibernateException { !N74y%=M
Criteria criteria = 9/PX~j9O?
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detachedCriteria.getExecutableCriteria(session); p?'
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return
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criteria.setProjection(Projections.rowCount YDaGr6y4i
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()).uniqueResult(); {4B7a6
} V>"NVRY
}, true); >a)6GZ@
return count.intValue(); =zRjb>
} J:dNV<A^
} ]htx9ds=
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用户在web层构造查询条件detachedCriteria,和可选的 *lyRy/POB
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 kj@m5`G
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PaginationSupport的实例ps。 P`y 0FKS
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ps.getItems()得到已分页好的结果集 e$4l[&kH_
ps.getIndexes()得到分页索引的数组 $Hal]
ps.getTotalCount()得到总结果数 `_E@cZ4
ps.getStartIndex()当前分页索引 , R $ZZ4
ps.getNextIndex()下一页索引 bX`VIFc
ps.getPreviousIndex()上一页索引 .xg, j{%(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 g({dD;
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 +"D*0gYD
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一下代码重构了。 N}7tjk
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我把原本我的做法也提供出来供大家讨论吧: Ks.kn7<l
Ng1uJa[k!d
首先,为了实现分页查询,我封装了一个Page类: 2w67>w\
java代码: ^?gs<-)B
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/*Created on 2005-4-14*/ /@f3|L<1@V
package org.flyware.util.page; ,XmyC7y<
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/** roE*8:Y
* @author Joa ?o.Q
* s(M8 Y
*/ Wf:I
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publicclass Page { ypsT:uLT
*8j2iu-|
/** imply if the page has previous page */ ;c;PNihg
privateboolean hasPrePage; |\S p IFH1
mLL?n)
/** imply if the page has next page */ e$y VV#
privateboolean hasNextPage; pm}!?TL
m@^!?/as
/** the number of every page */ k-a3oLCR,
privateint everyPage; KsBi<wY
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/** the total page number */ H}B%OFI \+
privateint totalPage; -VlXZj@u+
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"
/** the number of current page */ q(I`g;MF
privateint currentPage; h$~\to$C
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/** the begin index of the records by the current Wa+q[E
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query */ x)Ls(Xh+g
privateint beginIndex; Z/hgr|&}
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/** The default constructor */ yxz"9PE/P
public Page(){ _r&,n\
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}
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/** construct the page by everyPage bI"_hvcFp
* @param everyPage }{.0mu9
* */ xLmgr72D
public Page(int everyPage){
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this.everyPage = everyPage; f Nnemn@>
} qoXncdDHZ
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/** The whole constructor */ $06[D91'
public Page(boolean hasPrePage, boolean hasNextPage, 96FS-`
@ = M:RA
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int everyPage, int totalPage, gLL8-T[9
int currentPage, int beginIndex){ hPB^|#}
this.hasPrePage = hasPrePage; -]K9sy)I
this.hasNextPage = hasNextPage; nPU=n[t8O
this.everyPage = everyPage; q/lQEfR
this.totalPage = totalPage; k ED1s's
this.currentPage = currentPage; }[>X}"_e
this.beginIndex = beginIndex; 2/W5E-tn
} X5gI'u
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/** hvO
* @return EDf"1b{PX
* Returns the beginIndex. AYP*J
*/ [,)G\
publicint getBeginIndex(){ :K)7_]y
return beginIndex; $ rU"Krf67
} %H AforH
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/** 3\B28m
* @param beginIndex t3//
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* The beginIndex to set. !\6<kQg#
*/ "h'+!2mf
publicvoid setBeginIndex(int beginIndex){ NlG~{rfI
this.beginIndex = beginIndex; CVy\']
} O DO'!T-
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/** l3O!{&~K
* @return psFY=^69o
* Returns the currentPage. aVvma=
*/
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publicint getCurrentPage(){ rn9n _)
return currentPage; !jTtMx
} LpYG!K l
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/** `]7==c #Y
* @param currentPage )4MM>Q
* The currentPage to set. M(/ATOJ(
*/ rLpfybu
publicvoid setCurrentPage(int currentPage){ S
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this.currentPage = currentPage; 2if7|o$=
} R0g^0K.
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/** {)jTq??
* @return ;0vCZaEF
* Returns the everyPage. o"!C8s_6
*/ @u @~gEt
publicint getEveryPage(){ m!K`?P]:N
return everyPage; JyO2P
} 4=~+Bz
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/** :;hz!6!
* @param everyPage HSk_'g(\0
* The everyPage to set. y '[VZ$^i
*/ 48IrC_0j
publicvoid setEveryPage(int everyPage){ %b[>eIJU#
this.everyPage = everyPage; /rIyW?& f
} D"V(A \sZ
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/** uc>":V
* @return uCr :+"C
* Returns the hasNextPage.
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*/ g\% Z+Dc
publicboolean getHasNextPage(){ l0 8vF$k|d
return hasNextPage; Fq$r>tmV
} 3_ly"\I\
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/** vSu
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* @param hasNextPage jF}-dfe
* The hasNextPage to set. Kl,NL]]4*5
*/ %s! |,Cu
publicvoid setHasNextPage(boolean hasNextPage){ 4{@{VsXN
this.hasNextPage = hasNextPage; eaC%&k
} xg}Q~,:
n$F~
/**
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* @return E<jW;trt_
* Returns the hasPrePage. I>GBnx
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*/ kuI~lBWI
publicboolean getHasPrePage(){ ?<`oKBn
return hasPrePage; ~Pj q3etk
} :r(dMU3%
Xhq7)/jp
/** aeISb83Y |
* @param hasPrePage WfD fj
* The hasPrePage to set. Khb Ku0Z
*/ RG*Vdom
publicvoid setHasPrePage(boolean hasPrePage){ sH.=Faos
this.hasPrePage = hasPrePage; 41x"Q?.bY
} +fvD1xHI
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/** xeL"FzF:V
* @return Returns the totalPage. ~o>Gm>5!HH
* lLp,sNAj
*/ f1]zsn:
publicint getTotalPage(){ -72EXO=|
return totalPage; TF%Xb>jy[
} 4-t^?T:qF
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/** pB4Uc<e
* @param totalPage FieDESsX>
* The totalPage to set. `sCn4-$8
*/ u4_QLf@I
publicvoid setTotalPage(int totalPage){ F#>00b{Q
this.totalPage = totalPage; 'f!U[Qatg
} <^\rv42'(2
{nbT$3=Zt
} Kp6 @?
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ni&|;"Nt-
]q.%_
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 J Cq>;br.
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个PageUtil,负责对Page对象进行构造: &s='$a;4
java代码: z7ik/>d?
v !8=B21
~%8P0AP
/*Created on 2005-4-14*/ X3\PVsH$K
package org.flyware.util.page; &yvvea]
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import org.apache.commons.logging.Log; ;U|(rM;
import org.apache.commons.logging.LogFactory; Xva(R<W7d<
V6X )L>!xx
/** VD$5 Djq
* @author Joa ;NR|Hi]
* l cie6'<
*/ N#K)Z5J)b
publicclass PageUtil { 8u2k-_9
b)<WC$"
privatestaticfinal Log logger = LogFactory.getLog "5&"Ij,/
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(PageUtil.class); rXi&8R[
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/** 68XJ`/d
* Use the origin page to create a new page Lw}-oE
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* @param page d ItfR'$
* @param totalRecords byxlC?q7
* @return ]~aj
*/ taE
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publicstatic Page createPage(Page page, int LN|(Z*
m ol,iM*l
totalRecords){ Y(g_h:lf,]
return createPage(page.getEveryPage(), Hu"$)V
'F d+1
3
page.getCurrentPage(), totalRecords); 2iG+Ek-?"
} 8Yh'/,o=L#
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/** .; F<X\_
* the basic page utils not including exception ,`}yJ*7
pi?/]}:
handler ,~Mf2Y#m0p
* @param everyPage = LNU%0m
* @param currentPage J\y^T3Z
* @param totalRecords H~Uf2A)C
* @return page .;4N:*hY
*/ V
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publicstatic Page createPage(int everyPage, int :}e<
b* n3Fej
currentPage, int totalRecords){ f)*?Ji|5F
everyPage = getEveryPage(everyPage); <D.E.^Y
currentPage = getCurrentPage(currentPage); \6|y~5Hw{r
int beginIndex = getBeginIndex(everyPage, sfX~X/
8g0 #WV
currentPage); HPt3WBRzS;
int totalPage = getTotalPage(everyPage, cb^IJA9}
C~h#pAh
totalRecords); ;\7`G!q
boolean hasNextPage = hasNextPage(currentPage, @rYZ0`E9
OkciL]
totalPage); a fa\6]m
boolean hasPrePage = hasPrePage(currentPage); zDdo RK@
*|y'%y
returnnew Page(hasPrePage, hasNextPage, nX!%9x$3
everyPage, totalPage, BQ6$T&
currentPage, MLV]+H[mt
!
v![K
beginIndex); nGVr\u9z
} E!Q@AZ
c +]r
privatestaticint getEveryPage(int everyPage){ q]="ek&_
return everyPage == 0 ? 10 : everyPage; k{f1q>gd
} NOTG|\{
&u:U"j
privatestaticint getCurrentPage(int currentPage){ 0aY|:
return currentPage == 0 ? 1 : currentPage; Qr
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} |B(,53
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Y
privatestaticint getBeginIndex(int everyPage, int N6[Z*5efR
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currentPage){ Z2W&_(^.h
return(currentPage - 1) * everyPage; r.?dT |A
} L"YQji!
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privatestaticint getTotalPage(int everyPage, int 1jx?zvE,
>(2;(TbQm0
totalRecords){ SVa^:\"$[
int totalPage = 0; gkK(7=r%
8;qOsV)UDT
if(totalRecords % everyPage == 0) ^X#)'\T
totalPage = totalRecords / everyPage; eV_",W
else 0Y0z7A:
totalPage = totalRecords / everyPage + 1 ; Wgf
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return totalPage; "'DPb%o
} 6<z#*`U1
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privatestaticboolean hasPrePage(int currentPage){ C,ldi"|
return currentPage == 1 ? false : true; VnN(lJ
} <e Y2}Ml
"X<V>q$0~c
privatestaticboolean hasNextPage(int currentPage, 7IUJHc[R?
"S@]yL
int totalPage){ 1^AQLOiRE1
return currentPage == totalPage || totalPage == y@}WxSK*0
Urw =a$
0 ? false : true; C|
} ?z.
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} 8I*yS#
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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。 ?5G;=#I
af[dkuv
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 mJ8EiRSE
']!wc8m1"
做法如下: !FK)iQy$0
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 2*W|s7cc
R<3 -!p1v
的信息,和一个结果集List: IM,d6lN6s
java代码: 1q
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/*Created on 2005-6-13*/ [:izej(\
package com.adt.bo; F.Bij8\
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import java.util.List; >y!R}`&0^t
PE_JO(e;Xm
import org.flyware.util.page.Page; [$]-W$j+
ocS}4.a@
/** Dl?:Mh
* @author Joa DLq'V.M:
*/ -lfbn=3
publicclass Result { )*}?EI4.
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private Page page; sVlQ5M oo(
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private List content; x=W5e
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/** /*6[Itm_h
* The default constructor iII%!f?{[
*/ eS%8WmCV9<
public Result(){ &j"_hFhv
super(); {XXnMO4uR;
} '~{kR=+
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/** -|:mRAe
* The constructor using fields MbQ%'z6D
* \Jwc[R&x
* @param page 7a4Z~r27/
* @param content *y~~~ 'J/
*/ LmKY$~5P
public Result(Page page, List content){ NiVZ=wEp,
this.page = page; tt&{f <*
this.content = content; /RF&@NJE5
} ?%T]V+40
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/** K7,Sr1O `
* @return Returns the content. OP``+z>
*/ AgOti]`aR
publicList getContent(){ XS>( Bu
return content; ,y)V5
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} #Fh:z4
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/** z|<?=c2P
* @return Returns the page. %y+v0.aWH+
*/ u} [.*e
public Page getPage(){ >=Na, D
return page; Wm!cjGK
} q^}iXE~
m*14n_m'
/** X|Nb81M
* @param content =_$Hn>vO
* The content to set. AD7&-=p&w
*/ &8JK^zQq
public void setContent(List content){ -{p~sRc&
this.content = content; 2}9M7Z",2
} wYd{X 8$
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/** 3g3Znb
* @param page \
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* The page to set. C:vVFU|4
*/ cE*d(g
publicvoid setPage(Page page){ .6pVt_f0/
this.page = page; G9~ 4?v6:
} /kqa|=-`q
} % 3<7HY]~
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2. 编写业务逻辑接口,并实现它(UserManager, d M;v39
4
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UserManagerImpl) Wfsd$kN6{
java代码: ,HK-mAH
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CPA!
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/*Created on 2005-7-15*/ Upz?x{>x
package com.adt.service; 8-x)8B
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import net.sf.hibernate.HibernateException; yXCHBz 6&
X?'pcYSL
import org.flyware.util.page.Page; 5a5)hmO RB
[6\b(kS+
import com.adt.bo.Result; pL,l
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/** Q6xA@"GJ
* @author Joa lLS7K8;4W
*/ U,Fyi6{~
publicinterface UserManager { 8Y/1+-
D"&Sd@a{
public Result listUser(Page page)throws T _fM\jdI
0@Z}.k30
HibernateException; !gJw?(8"
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} ~re~Ys
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+tJ 7ZR%
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9A *gW j
java代码: l_Zx'm
x
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/*Created on 2005-7-15*/ 6i%Xf i
package com.adt.service.impl; \J(kM,ZJ
od^ylg>K
import java.util.List; BO.Db``
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import net.sf.hibernate.HibernateException; w@LLxL>Y
\J;_%-Z
import org.flyware.util.page.Page; <6X*k{
import org.flyware.util.page.PageUtil; hw=~%f;
n/S+0uT
import com.adt.bo.Result; "<LWz&e^^
import com.adt.dao.UserDAO; BAtjYPX'w
import com.adt.exception.ObjectNotFoundException; /@I`V?Q!a
import com.adt.service.UserManager; /*MioaQB}p
=nqHVRA
/** 8{_lB#<[E
* @author Joa .eLd0{JtN
*/ 4issj$
publicclass UserManagerImpl implements UserManager { l2I%$|)d
D"%>
private UserDAO userDAO; 73Hm:"Eqd
'xEK0~awD
/** F~eY'~&H}
* @param userDAO The userDAO to set. (e0(GOqf4
*/ aemi;61T\
publicvoid setUserDAO(UserDAO userDAO){ <y?=;54a
this.userDAO = userDAO; +wf9!_'
} 7Gy:T47T\@
J_?v=dW`
/* (non-Javadoc) dCeLW
* @see com.adt.service.UserManager#listUser mhy='AQJ
!#=3>\np+X
(org.flyware.util.page.Page) $sS~hy*
*/ l qKj;'
public Result listUser(Page page)throws eTuKu(0
E
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HibernateException, ObjectNotFoundException { ,Vw>3|C
int totalRecords = userDAO.getUserCount(); w
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if(totalRecords == 0) e[s}tjx
throw new ObjectNotFoundException 0[e!/*_V
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("userNotExist"); Wky9wr:g
page = PageUtil.createPage(page, totalRecords); lRb>W31"
List users = userDAO.getUserByPage(page); ~?FhQd\Q
returnnew Result(page, users); P=_fYA3
} E&eY79
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} I]E 3&gnC
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Ikw@B)0}
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9z
询,接下来编写UserDAO的代码: *BdH
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3. UserDAO 和 UserDAOImpl: sRA2O/yKCE
java代码: "RN]
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EK Vcz'w
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/*Created on 2005-7-15*/ &JcatI
package com.adt.dao; b^Re947{g
mO;QT
import java.util.List; *=.~PR6W{
hlB\Xt
import org.flyware.util.page.Page; XUA@f*
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import net.sf.hibernate.HibernateException; YrB-n
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/** b&mA1w[W]
* @author Joa 6]Is"3ca
*/ ; Byt'S
publicinterface UserDAO extends BaseDAO { nqm=snh
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publicList getUserByName(String name)throws V<J1.8H
?'z/S5&j
HibernateException; BB\GrD
fy4zBI@
publicint getUserCount()throws HibernateException; o+'|j#P
YE~IO5
publicList getUserByPage(Page page)throws } &B6
hdHz", )
HibernateException; j2<+[h-
ld@+p
} 94BH{9b5
1+uZF
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jez0 A
)>:~XA|?
java代码: 3ai[ r
JM|HnyI
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/*Created on 2005-7-15*/ ?J2A1iuq3
package com.adt.dao.impl; -je} PwT
X]p3?"7
import java.util.List; E6TeZ%g
R+Hu?Dv&F
import org.flyware.util.page.Page; 7,+eG">0
,s #~00C|
import net.sf.hibernate.HibernateException; $h{m")]
import net.sf.hibernate.Query; @"MYq#2c$
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import com.adt.dao.UserDAO; /B@{w-N
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/** 7sxX?u
* @author Joa YQG<Q
*/ FfJ;r'eGs
public class UserDAOImpl extends BaseDAOHibernateImpl dgkS5Q$/
V2Vr7v=Y"
implements UserDAO { b?i+nhqI
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/* (non-Javadoc) +M0pmK!
* @see com.adt.dao.UserDAO#getUserByName -<s Gu9
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(java.lang.String) lLTqk\8g
*/ "#r)NYq`"|
publicList getUserByName(String name)throws mZR3Hl$
u[b |QR=5
HibernateException { lA5Dag'
String querySentence = "FROM user in class H`CID*Ji
\0b}Z#'0
com.adt.po.User WHERE user.name=:name"; VV$t*9w
Query query = getSession().createQuery &