Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 A,3qjd,$ c
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 !t\sg
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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 vb}c)w
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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 [8K :ml
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分页支持类: s d = bw
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java代码: %P:|B:\<
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package com.javaeye.common.util; <qEBF`XP =
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import java.util.List; Ge^,hAM'
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publicclass PaginationSupport { G\^<MR|
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publicfinalstaticint PAGESIZE = 30; 1/K1e$r
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privateint pageSize = PAGESIZE; m_,Jbf
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privateList items; 6\`8b&'n
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privateint totalCount; D0z[h(m
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privateint[] indexes = newint[0]; @AK&R~<
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privateint startIndex = 0; sf:IA%.4t
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public PaginationSupport(List items, int Hi*|f!,H?
1}+b4"7]
totalCount){ lcgG5/82
setPageSize(PAGESIZE); V`HnFAW
setTotalCount(totalCount); B<n[yiJ}
setItems(items); g,W34*7=Q
setStartIndex(0); _6'@#DN
} PN:`SWP
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public PaginationSupport(List items, int 62y:i
"fUNrhCx
totalCount, int startIndex){ axq~56"7E
setPageSize(PAGESIZE); \u))1zRd
setTotalCount(totalCount); EuImj#Zl
setItems(items); }^j8<
setStartIndex(startIndex); 99CK [G
} :8==Bu
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public PaginationSupport(List items, int %[M0TE=J
hw*u. 46
totalCount, int pageSize, int startIndex){ GIn%yB'
setPageSize(pageSize); h.KgHMV`
setTotalCount(totalCount); =tP^vgfQ
setItems(items); tE <?L
setStartIndex(startIndex); Gf:dN_e6.
} c_?^:xs:d
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publicList getItems(){ !
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return items; dU2;
} Oh>hyY)}
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publicvoid setItems(List items){ d_0(;'
this.items = items; r|jM;
} MPy><J
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publicint getPageSize(){ EltCtfm`
return pageSize; }Nwp{["}]L
} ,Z _@]D@
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publicvoid setPageSize(int pageSize){ !MOsP<2
this.pageSize = pageSize; 3 H5
} hsS&|7Pt
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publicint getTotalCount(){ r
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return totalCount; VBF:MAA
} 1_v\G
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publicvoid setTotalCount(int totalCount){ "::2]3e
if(totalCount > 0){ W*CRxGyZCl
this.totalCount = totalCount; VNIl%9:-l
int count = totalCount / z=g!mVK5
% XZ&(
pageSize; ilHf5$
if(totalCount % pageSize > 0) hfyU}`]
count++; yt="kZ
indexes = newint[count]; <OKc?[
for(int i = 0; i < count; i++){ g52)/HM
indexes = pageSize * QT^b-~^
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i; II.:k.D`
} qm:C1#<p
}else{ 2ww
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this.totalCount = 0; m*N8!1Ot
} " M?dU^U^
} ~+Pe=~a[
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publicint[] getIndexes(){ ;DYS1vG o
return indexes; >(.|oT\Tb
} Cb+$|Kg/"b
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publicvoid setIndexes(int[] indexes){ UdM2!f
this.indexes = indexes; 4m91XD
} y2s(]#8
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publicint getStartIndex(){ 7g+T
return startIndex; w?|qKO
} T@IzfX7
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publicvoid setStartIndex(int startIndex){ };9s8VZE
if(totalCount <= 0) .<z7$lz\
this.startIndex = 0; &,jUaC5I
elseif(startIndex >= totalCount) ]k7%p>c=B
this.startIndex = indexes Q8m%mJz~]
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[indexes.length - 1]; *!&?Xy%\"j
elseif(startIndex < 0) C12V_)~2
this.startIndex = 0; _",(!(
else{ tm=,x~
this.startIndex = indexes 6?<lS.s
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[startIndex / pageSize]; :" !Z9l\@
} ;)CN=J!
} tNzO1BK
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publicint getNextIndex(){ %~Rg`+
int nextIndex = getStartIndex() + 2xO[ ?fR
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pageSize; }Cw,m0KV/
if(nextIndex >= totalCount) GEf=A.WAfw
return getStartIndex(); `Tyd1!~
else 2!B|w8ar
return nextIndex; X5J )1rL
} >(igVaZ>
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publicint getPreviousIndex(){ CQ/+- -o
int previousIndex = getStartIndex() - $RY GAh
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pageSize; [y'blCb
if(previousIndex < 0) zE$HHY2ovi
return0; *|\bS "
else -A
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return previousIndex; zqNzWX
} |LQ%sV
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} :g63*d+/G
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抽象业务类 n)q8y0if
java代码: MW rhVn{R
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/** d>)=|
* Created on 2005-7-12 `Pj7:[."[
*/ [}HPV+j=U
package com.javaeye.common.business; V>)/z|[
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import java.io.Serializable; h?n?3x!(
import java.util.List; dNt^lx
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import org.hibernate.Criteria; #?S"y:
import org.hibernate.HibernateException; z3S"1L7
import org.hibernate.Session; ?B ,<gen
import org.hibernate.criterion.DetachedCriteria; aanS^t0
import org.hibernate.criterion.Projections; K(upzn*a
import &&C70+_po
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org.springframework.orm.hibernate3.HibernateCallback; Posz|u<x
import A? B+
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org.springframework.orm.hibernate3.support.HibernateDaoS '12*'Q+{+
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upport; R~a9}&
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import com.javaeye.common.util.PaginationSupport; *> nOL
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public abstract class AbstractManager extends Sq,>^|v4&e
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HibernateDaoSupport { ^\B4]'+^j
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privateboolean cacheQueries = false; |33t 5}we
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privateString queryCacheRegion; c8mh#Tbl
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publicvoid setCacheQueries(boolean 3^
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cacheQueries){ dYD;Z<l
this.cacheQueries = cacheQueries; Rf`_q7fm
} B$2GEg]Ri
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publicvoid setQueryCacheRegion(String 80Hi v
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queryCacheRegion){ O(%6/r`L,k
this.queryCacheRegion = #3_g8ni5X
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queryCacheRegion; R$l-
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} 7:LEf"vRZ
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publicvoid save(finalObject entity){ zT)cg$8%fY
getHibernateTemplate().save(entity); .>TG{>sH
} Ua|iAD1
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publicvoid persist(finalObject entity){ S{l)hwlE
getHibernateTemplate().save(entity); Q .Nw#r+m
} /# Jvt
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publicvoid update(finalObject entity){ gd#R7[AVi
getHibernateTemplate().update(entity); +j F|8
}
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publicvoid delete(finalObject entity){ xva
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getHibernateTemplate().delete(entity); -7w}+iS
} bl>W i@GL
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publicObject load(finalClass entity, ]s5e[iS
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finalSerializable id){ 5>%^"f
return getHibernateTemplate().load U`3?bhzua
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(entity, id); xa'U_]m
} V#$QKn`;
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publicObject get(finalClass entity, ,sc#l<v
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finalSerializable id){ ?K pDEH~\
return getHibernateTemplate().get d m"R0>
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(entity, id); 9*FA=E
} _J\zj
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publicList findAll(finalClass entity){ 4.,|vtp
return getHibernateTemplate().find("from 3,G|oR{D
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" + entity.getName()); .{ILeG
} gh[q*%#
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publicList findByNamedQuery(finalString 8iD7K@
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namedQuery){ 1&e8vVN
return getHibernateTemplate `UzH *w@e
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().findByNamedQuery(namedQuery); D+0il=5
} Rh6CV
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publicList findByNamedQuery(finalString query, y=\&z&3$
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finalObject parameter){ -}T7F+
return getHibernateTemplate +|S)Mm8-
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().findByNamedQuery(query, parameter); rr`_\ut
} {-7ovH?
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publicList findByNamedQuery(finalString query, [?<v|k
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finalObject[] parameters){ x%$6l
return getHibernateTemplate ]S?G]/k}
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().findByNamedQuery(query, parameters); 4?(=?0/[
} S]fkA6v
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publicList find(finalString query){ E 8W*^^z(
return getHibernateTemplate().find Z[z" v
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(query); !7]^QdBLY
} 2|exY>`w
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publicList find(finalString query, finalObject yP-$@Ry
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parameter){ lv.h?"Ml
return getHibernateTemplate().find %y>*9$<pXe
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(query, parameter); 874j9ky[
} (NnE\2
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public PaginationSupport findPageByCriteria Gyi0SM6v5&
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(final DetachedCriteria detachedCriteria){ ~|{e"!(}
return findPageByCriteria [UdJ(cGf
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); YyYp-0#
} fWg3gRI
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public PaginationSupport findPageByCriteria ed/
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(final DetachedCriteria detachedCriteria, finalint :=quCzG
/ 8dRql-Ne
startIndex){ N-p||u
return findPageByCriteria - sq=|
WT 5 2
(detachedCriteria, PaginationSupport.PAGESIZE, 'UCClj;?K
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startIndex); u8x#XESR7
} b9Eb"
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public PaginationSupport findPageByCriteria 7/=r-
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(final DetachedCriteria detachedCriteria, finalint gazX2P[D
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pageSize, 6%c]{eTd9
finalint startIndex){ RbA.&=3
return(PaginationSupport) 3P'Wk|j
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getHibernateTemplate().execute(new HibernateCallback(){ _4lKd`
publicObject doInHibernate @C~gU@F
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(Session session)throws HibernateException { !|,djo!N
Criteria criteria = *u>[
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detachedCriteria.getExecutableCriteria(session); @# p{,L
int totalCount = ~f8:sDJ
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((Integer) criteria.setProjection(Projections.rowCount I<&) P#"
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()).uniqueResult()).intValue(); =#I/x=L:
criteria.setProjection KW36nY\7
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(null); a0wpsl
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List items = vWYU'_=
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criteria.setFirstResult(startIndex).setMaxResults l8DZ2cw]
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(pageSize).list(); :u?L
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PaginationSupport ps = gF|u%_y-qt
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new PaginationSupport(items, totalCount, pageSize, u>03l(X6f
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startIndex); 5q}7#{A
return ps; RDu{U(!
} ~N+H7T.L
}, true); o7fJ@3B/
} Gd[:&h
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public List findAllByCriteria(final ?$H=n{iW
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DetachedCriteria detachedCriteria){ yzL6oU-{&
return(List) getHibernateTemplate u5P2*
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().execute(new HibernateCallback(){ y>JSo9[@
publicObject doInHibernate #<R6!"TNoz
@aWd0e]
(Session session)throws HibernateException { 8SO(pw9
Criteria criteria = FlLk.+!t
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detachedCriteria.getExecutableCriteria(session); ;c# jO:A5
return criteria.list(); x?G"58
} K|wB0TiXP
}, true);
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} 6"c(5#H
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public int getCountByCriteria(final 1n>(CwLG"
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DetachedCriteria detachedCriteria){ Wtj*Z.=:
Integer count = (Integer) TDW\n
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getHibernateTemplate().execute(new HibernateCallback(){ @VKN6yHH
publicObject doInHibernate B d?{ldg
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(Session session)throws HibernateException { o;{BI
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Criteria criteria = zHQSx7Ow 5
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detachedCriteria.getExecutableCriteria(session); u'"]{.K>fb
return = _/XFN
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criteria.setProjection(Projections.rowCount 39Tlt~Psz
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()).uniqueResult(); Au{J/G<W@
} c[4I> "w
}, true); =a_ >")
return count.intValue(); %2`.*]L
} pn
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} ,uCgC4EP
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用户在web层构造查询条件detachedCriteria,和可选的 Dq9*il;'
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *L#\#nh7
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PaginationSupport的实例ps。 yey]#M[y
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ps.getItems()得到已分页好的结果集 Na$[nv8qh
ps.getIndexes()得到分页索引的数组 h%>yErs
ps.getTotalCount()得到总结果数 (cm8x
ps.getStartIndex()当前分页索引 EVDcj,b"^
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 cPPTGpqw
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %<^j=K= 0
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 BKd?%V8:Q
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一下代码重构了。 T3h 1eU
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我把原本我的做法也提供出来供大家讨论吧: NbUbLzE
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首先,为了实现分页查询,我封装了一个Page类: "{M?,jP#
java代码: v]hu5t
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/*Created on 2005-4-14*/ dc,qQM
package org.flyware.util.page; b-HELS`nX
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/** E5g|*M.+f
* @author Joa &ZI-#(P
* U*7x81v?j
*/ |?4NlB6
publicclass Page { "WzD+<oL
-nDY3$U/
/** imply if the page has previous page */ b>L?0p$ej
privateboolean hasPrePage; z^\-x9vL
q:u,)6
/** imply if the page has next page */ tYMPqP,1.
privateboolean hasNextPage; 1}3tpO;
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/** the number of every page */ gvoYyO#cm
privateint everyPage; `zsooA
Gt
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/** the total page number */ W7"UhM
privateint totalPage; y1 a1UiHGP
r>B|JPm
/** the number of current page */ :?SD#Vvrh.
privateint currentPage; !TLJk]7uC
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/** the begin index of the records by the current %`}nP3
U[W &D%'
query */ dK>sHUu
privateint beginIndex; LyRW\\z2
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/** The default constructor */ 1\-r5e; BE
public Page(){ x%T.0@!8
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} Q2<v: *L
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/** construct the page by everyPage K>G.HN@
* @param everyPage h`f $]_c
* */ Ik-E_U2
public Page(int everyPage){ y'(a:.%I
this.everyPage = everyPage; VE?Aa
} $0|`h)&
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/** The whole constructor */ AejM\#>
public Page(boolean hasPrePage, boolean hasNextPage, 5:(/k\9+yv
6o4Y]C2W{1
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int everyPage, int totalPage, DGNn#DP
int currentPage, int beginIndex){ P=R-1V
this.hasPrePage = hasPrePage; C%H?vrR
this.hasNextPage = hasNextPage; afE)yu`
this.everyPage = everyPage; ]Hg6Mz>Mj
this.totalPage = totalPage; m~-O}i~)
this.currentPage = currentPage; (#8B
this.beginIndex = beginIndex; z0@BBXQ`
} ox5WboL
Z?u}?-b1\H
/** DhXV=Qw
* @return UjS+Ddp
* Returns the beginIndex. /[E2+g
*/ b>Ea_3T/
publicint getBeginIndex(){ zxkO&DGRbN
return beginIndex; ~I;|ipK4m
} |G_, 1$
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/** 2"_5Yyb
* @param beginIndex *Sps^Wl
* The beginIndex to set. O_L>We@3E
*/ a[p$e?gka
publicvoid setBeginIndex(int beginIndex){ 2S-f5&o
this.beginIndex = beginIndex; #_WkV
} N5zx# g
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/** `\GRY @cg
* @return \,'4eV
* Returns the currentPage. qiH)J-
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*/ J&&)%&h'I
publicint getCurrentPage(){ }42Hhu7j
return currentPage; E;wT4 T=
} RAWzQE}
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/** *Qyu
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* @param currentPage &4ndi=.#rg
* The currentPage to set. b[<L
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*/ A]ZQ?-L/
publicvoid setCurrentPage(int currentPage){ LW k/h1
this.currentPage = currentPage; W8F@nY
} sR/y|
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/** 5)A[NTNJx
* @return .5);W;`X
* Returns the everyPage. q;*'V9#
*/ d"L(eI}G
publicint getEveryPage(){ (4?^X
return everyPage; =cO5Nt
} IwRP,MQ~
hu.p;A3p;
/** >@Pw{Zh$
* @param everyPage MJkusR/
* The everyPage to set. c-_1tSh}
*/ P+BGCc%);B
publicvoid setEveryPage(int everyPage){ X&IT s
this.everyPage = everyPage; LH.Gf
} m#[9F']Z`
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/** B):ZX#
* @return 9MH;=88q
* Returns the hasNextPage. "U+c`V=w
*/ (<rE1w2s:
publicboolean getHasNextPage(){ <v/aquLN
return hasNextPage; :,fT^izew
} Zu2`IzrG#
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/** vG7Mk8mIr
* @param hasNextPage 1rs.
* The hasNextPage to set. :!hO9ho
*/ !&:Cp_
publicvoid setHasNextPage(boolean hasNextPage){ ?8/r=
this.hasNextPage = hasNextPage; zliMG=6
} )Ly~\*
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/** &*Xrh7K2e
* @return d2d8,Vg
* Returns the hasPrePage. &n6L;y-
*/ E0/>E
publicboolean getHasPrePage(){ #-PMREgO
return hasPrePage; |?ZU8I^vW
} ycSGv4
)
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/** fj/L)i
* @param hasPrePage @3$ I
* The hasPrePage to set. :J_UXtx
*/ #Hz9@H
publicvoid setHasPrePage(boolean hasPrePage){ 'CSjj@3 X
this.hasPrePage = hasPrePage; _iCrQJ0"T
} m5&Ht (I%n
X)6 G :cD
/** l0;u$
* @return Returns the totalPage. ]uF7HX7F
* E_I-.o|
*/ t- TUP>_
publicint getTotalPage(){ .c&&@>m@.
return totalPage; V8nQ/9R;
} tQRbNY#}Z
GyMN;|
/** /W`CqJk-*.
* @param totalPage _KKux3a
* The totalPage to set. F(zCvT
*/ ju3@F8AI
publicvoid setTotalPage(int totalPage){ :*BN>*1^\r
this.totalPage = totalPage; :3XvHL0rx
} _'17C/
lZ)6d-vK
} }st~$JsV1
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9C2pGfEbn}
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#d3_7rI0V
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 V= p"1!(
-s!J3DB
个PageUtil,负责对Page对象进行构造: D\+x/r?-I
java代码: 4H;7GNu
GD)paTwO<
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/*Created on 2005-4-14*/ (gPB@hAv
package org.flyware.util.page; B~k{f}
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import org.apache.commons.logging.Log; _
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import org.apache.commons.logging.LogFactory; H! 5Ka#B
8+dsTX`|S
/** R+0gn/a[ G
* @author Joa 0TA8#c
* ky]^N)
*/ ,/GFD[SQ
publicclass PageUtil { 5Za<]qxr
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privatestaticfinal Log logger = LogFactory.getLog rir,|y,
$xdo=4;|
(PageUtil.class); pfIK9>i
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/**
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* Use the origin page to create a new page Gey-8
* @param page _<jU! R
* @param totalRecords ,mvFeo;@f
* @return sC[#R.eq
*/ sk<S`J,M/_
publicstatic Page createPage(Page page, int 88X]Uw(+
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totalRecords){ D</?|;J#/
return createPage(page.getEveryPage(), Oi& 9FS
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page.getCurrentPage(), totalRecords); UMBeY[?
} xi.?@Lff
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/** N#jUqm
* the basic page utils not including exception COm^ti-p
3!@&7@p
handler @HB=hN
* @param everyPage D4(73
* @param currentPage frm[<-~ w0
* @param totalRecords Yc-5Mr8*,
* @return page E&z^E2
*/ FZ<6 kk4
publicstatic Page createPage(int everyPage, int ## vP(M$
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currentPage, int totalRecords){ W{!5}Sh
everyPage = getEveryPage(everyPage); J Q*~le*
currentPage = getCurrentPage(currentPage); !Sy9v
int beginIndex = getBeginIndex(everyPage, ".Q]FE@>
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currentPage); 1I'}Uh*
int totalPage = getTotalPage(everyPage, GHLnwym
R+He6c!?9
totalRecords); 5xnEkg4q4
boolean hasNextPage = hasNextPage(currentPage, IcQpbF0
s/~pr.>-l
totalPage); .,(x7?
boolean hasPrePage = hasPrePage(currentPage); i$3#/*Y7_L
jqj}j2
9
returnnew Page(hasPrePage, hasNextPage, }*%=C!m4R!
everyPage, totalPage, >wb*kyO7(#
currentPage, )v+&l9D
oNl-!W
beginIndex); N;P/$
} y
c<%f
d^$cx(2$D
privatestaticint getEveryPage(int everyPage){ GmJ
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return everyPage == 0 ? 10 : everyPage; zK1\InP
} {~}: oV
!=;Evf
privatestaticint getCurrentPage(int currentPage){ ]v@ng8
return currentPage == 0 ? 1 : currentPage; XAF]B,h=
} %jq
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[a$1{[|)
privatestaticint getBeginIndex(int everyPage, int xOg|<Nnl
*kF/yN
currentPage){ i>G:*?a
return(currentPage - 1) * everyPage; ^tm2Duv
} ;UX9Em
}V.fY3J-
privatestaticint getTotalPage(int everyPage, int >.C$2bW<L
%Gu=Dkz
totalRecords){ RiZ}cd
int totalPage = 0; Qd% (]L[N.
cw~GH
if(totalRecords % everyPage == 0) l,A\]QDvl
totalPage = totalRecords / everyPage; hhylsm
else =8p[ (<F=
totalPage = totalRecords / everyPage + 1 ; "Ya;&F.'
rc%*g3ryLG
return totalPage; u|EJ)dT?
} 4U)%JK.ta
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privatestaticboolean hasPrePage(int currentPage){ Sqmjf@o$>
return currentPage == 1 ? false : true; {BA Z`I
} Of-gG~
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privatestaticboolean hasNextPage(int currentPage, ^( C,LVP<
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int totalPage){ sZqi)lo-s
return currentPage == totalPage || totalPage == G~*R6x2g
YWi Y[
0 ? false : true; CSm(yB{|pC
} :t+LuH g
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} 95D(0qv
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7#*O|t/'
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 aM8z_j!!u
/~<Przw
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 MD> E0p)
waV4~BdL
做法如下: K~5(j{Kb8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,0>_(5
X)[QEq^
的信息,和一个结果集List: ;%u)~3B$JK
java代码: dwzk+@]8
V+*1?5w
kwt;pxp i
/*Created on 2005-6-13*/ ?0s&Kz4B
package com.adt.bo; SnO,-Rg
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import java.util.List; uA%F0oM
XT==N-5,
import org.flyware.util.page.Page; e=u}J%|
yaX%<KBa\
/** "rQ?2?
* @author Joa )[t3-'
*/ 1b!5h
publicclass Result { i2Gh!5]f
H{d/%}7[v
private Page page; U.WMu%
k}{K7,DM
private List content; DB] ]6
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/** KiNluGNt
* The default constructor L= <,+m[!
*/ uC`)?f*I
public Result(){ W?12'EG}xa
super(); JlH5 <:#PN
} LA837%)
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/** gD6BPW~0
* The constructor using fields a4!6K
* -32.g\]
* @param page +G!;:o
* @param content A)^A2xZQ
*/ ?[O Sy.6
public Result(Page page, List content){ l{\@+m
this.page = page; n8e}8.Bu
this.content = content; 3Q+THg3~?
} qSL~A-
KH1/B_.\V
/** X@B,w_b
* @return Returns the content. >Gxu8,_;
*/ B;L^!sLP
publicList getContent(){ 2)
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return content; H*dQT y,
} }KrZ6cG9#
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/** Tq >?.bq9
* @return Returns the page. W3i X;-Z
*/ |fm"{$u
public Page getPage(){ AyZBH&}RZ
return page; ~48mCD
} TqMy">>
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/** D#&N?<}
* @param content gLv";"4S
* The content to set. .J|"bs9
*/ ^`!EpO>k9
public void setContent(List content){ ^S`c-N
this.content = content; We#O'm
}
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/** -zLxT
* @param page (z<&PP
* The page to set. #bLeK$
*/ 1Xu^pc
publicvoid setPage(Page page){ %(wa~:m+S-
this.page = page; qdVExO&
} L~(`zO3f
} )u'("
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s"]LQM1|
%!1:BQ,p,i
jCbxI^3A
2. 编写业务逻辑接口,并实现它(UserManager, 1Q$Z'E}SK@
o%tvwv
UserManagerImpl) hu
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java代码: qu/59D
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EGyQhZ mO
/*Created on 2005-7-15*/ f8
M=P.jz
package com.adt.service; "^ cn9AG{
ve /Q6j{
import net.sf.hibernate.HibernateException; 8aD4wc
';!02=-@
import org.flyware.util.page.Page;
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import com.adt.bo.Result; Mzx y'UV
l4d2i;4BK
/** cS ;hyLd
* @author Joa KdOy3O_5N
*/ UvOB`Vj
publicinterface UserManager { ;wz
YZ5=Di
~Hs a6F&F
public Result listUser(Page page)throws KyAQzN 9
d&0^AvM@
HibernateException; iffRGnN^e
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} .)mw~ 3]
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Bf F$
O.*, e
mi3 yiR
java代码: Jh[fFg]
c X553&
l23#"gGb
/*Created on 2005-7-15*/ r>`65o
package com.adt.service.impl; V5RfxWtm:
0=&Hm).
import java.util.List; (_E<?
t*^Q`V wQ
import net.sf.hibernate.HibernateException; m^Btr
-pc*$oe
import org.flyware.util.page.Page; }S$]MY,*
import org.flyware.util.page.PageUtil; rRL:]%POT
(~N&ov
import com.adt.bo.Result; Qg9 N?e{z
import com.adt.dao.UserDAO; 2bfKD'!aH
import com.adt.exception.ObjectNotFoundException; +dk}$w[g
import com.adt.service.UserManager; RpR;1ktF>
]7-*1kL8=~
/** aDTNr/I
* @author Joa Y:/z)"u,C
*/ /e6\F7
publicclass UserManagerImpl implements UserManager { -D0kp~AO4N
">lu8F
private UserDAO userDAO; r+;op_
; 7[5%xM
/** X4lz?Y:*
* @param userDAO The userDAO to set. frk(2C8T
*/ [F/>pL5U$
publicvoid setUserDAO(UserDAO userDAO){ %<DXM`Y
this.userDAO = userDAO; :e`;["(,
} egxh
)VID
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/* (non-Javadoc) J"L+`i
* @see com.adt.service.UserManager#listUser U|={LU
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(org.flyware.util.page.Page) Mk7,:S
*/ OW\r }
public Result listUser(Page page)throws lO9ML-8C1
9H$#c_zrq
HibernateException, ObjectNotFoundException { Dx/BxqG6}_
int totalRecords = userDAO.getUserCount(); Q-_&5/G
if(totalRecords == 0) [84ss;.$
throw new ObjectNotFoundException &p%0cjg"Q
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("userNotExist"); ;z/Z(7<;;
page = PageUtil.createPage(page, totalRecords); u;GS[E4
List users = userDAO.getUserByPage(page); H[UV]qO,
returnnew Result(page, users); ;"$Wfy
} UmcPpZ
w
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} 9}p?h1NrY
3,=97Si=
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A}v!vVg
V}o`9R@tx}
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 '/%]B@!
4t]ccqX*{
询,接下来编写UserDAO的代码: ]1hW/!
3. UserDAO 和 UserDAOImpl: "`qmeZ$rg
java代码: uT:'Kkb!
:jlKj} 4A
3oc p4x`[
/*Created on 2005-7-15*/ <fg~+{PA&
package com.adt.dao; L&ucTc=
7ESSx"^B
import java.util.List; F_.rLgGY
CT,P Q
import org.flyware.util.page.Page; Oo^kV:.)
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g
import net.sf.hibernate.HibernateException; d$qivct
f]%:.N~1w
/** =jXBF.
* @author Joa jYDpJ##Zb
*/ q{T[|(!
publicinterface UserDAO extends BaseDAO {
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@lpo$lN0R
publicList getUserByName(String name)throws Htl2CcZ
{o1vv+i
HibernateException; @oE^(
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publicint getUserCount()throws HibernateException; E><$sN6
{\zTE1X9
publicList getUserByPage(Page page)throws 3/_rbPr
pGz 5!d
HibernateException; Rp.42v#ck
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} \#Md3!MG
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java代码: OlRtVp1
!r\u,l^
>TI/W~M
/*Created on 2005-7-15*/ r@")MOGc
package com.adt.dao.impl; (;\"
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8Of.n7{
import java.util.List; vH1IVF"DS
^UU@7cSi|G
import org.flyware.util.page.Page; B xAyjA6
{A^ 3<=|
import net.sf.hibernate.HibernateException; wwh1aV *
import net.sf.hibernate.Query; NM
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uuHg=8(
import com.adt.dao.UserDAO; EzII!0 F
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/** 0zQ~'x
* @author Joa mIW8K
):
*/ 75v7w
public class UserDAOImpl extends BaseDAOHibernateImpl YV%y
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implements UserDAO { }2xgm9j<
e= { ?d6
/* (non-Javadoc) BD.&K_AW
* @see com.adt.dao.UserDAO#getUserByName arK(dg~S
v']Tusmg
(java.lang.String)
4,g_$)
*/
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publicList getUserByName(String name)throws U:r^4,Mz*
r+TvC{
HibernateException { aH/8&.JLi
String querySentence = "FROM user in class ;Mw<{X-
Ms<v81z5T
com.adt.po.User WHERE user.name=:name"; J:Mn5hdK=
Query query = getSession().createQuery >c`r&W.t
h2jrO9
(querySentence); M!i["($_
query.setParameter("name", name); M r-l
return query.list(); Vh ?5
} kz0pX-@b
#~}4< 18
/* (non-Javadoc) -%fc)y&$
* @see com.adt.dao.UserDAO#getUserCount() +MR]h
[
*/ xig4H7V
publicint getUserCount()throws HibernateException { q$7w?(Lk
int count = 0; V36u%zdX5n
String querySentence = "SELECT count(*) FROM [_T6
Ly46S
user in class com.adt.po.User"; >O]u4G!
Query query = getSession().createQuery J,G/L!Bp
.R^R32ln
(querySentence); = }ELu@\V[
count = ((Integer)query.iterate().next s4uZ >
:>CD;
()).intValue(); _<Ip0?N
return count; U|
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} Sq]VtQ(
8q]_> X
/* (non-Javadoc) ^*G
UcQ$
* @see com.adt.dao.UserDAO#getUserByPage bblEZ%
t5CJG '!ql
(org.flyware.util.page.Page) .TeGA;
*/ Skl:~'W.&|
publicList getUserByPage(Page page)throws 5X PoQ^
5Lm-KohT'
HibernateException { ;.66phe
String querySentence = "FROM user in class dvE~EZcS
42f\]R,
com.adt.po.User"; TO&^%d
Query query = getSession().createQuery QsX`IYk
M1z ?E@kz
(querySentence); <<DPer2
query.setFirstResult(page.getBeginIndex()) r}:Dg
fn
.setMaxResults(page.getEveryPage()); %0p9\I
return query.list(); B.A;1VE5
} Ip<