Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _YF%V;X
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^tXJj:wtS
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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 .A6(D$O k
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 7b<yVP;{
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分页支持类: HD(.BW7
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java代码: s`0QA!G{-
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% LJs
package com.javaeye.common.util; J>/w5$h5
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import java.util.List; x
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publicclass PaginationSupport { {)-aSywe
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publicfinalstaticint PAGESIZE = 30; ^MVkZ{gtre
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privateint pageSize = PAGESIZE; L'F<ev
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privateList items; 6L)%T02C
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privateint totalCount; R)c'#St
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privateint[] indexes = newint[0]; nw-I|PVTNa
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privateint startIndex = 0; J>\B`E
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public PaginationSupport(List items, int t^w"w`v\u
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totalCount){ xXM{pd
setPageSize(PAGESIZE); utIX %0
setTotalCount(totalCount); Nqu>6^-z0
setItems(items); t25,0<iW
setStartIndex(0); e d<n9R
} ]w.;4`l*
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public PaginationSupport(List items, int [D!jv"
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totalCount, int startIndex){ ^/r7@:
setPageSize(PAGESIZE); m@^1JlH
setTotalCount(totalCount); DCZ\6WY1G)
setItems(items); yxH ( c
setStartIndex(startIndex); ?Orxmxc
2
} ]wtb-PC
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public PaginationSupport(List items, int <WcR,d
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totalCount, int pageSize, int startIndex){ uXKERzg
setPageSize(pageSize); Ry'= ke
setTotalCount(totalCount); jrS[f
setItems(items); 1&-
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setStartIndex(startIndex); )'~6HO8Z
} [<6S%s
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publicList getItems(){ {HCzp,Y
return items; Rp5#clsy
} ?#45wC
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publicvoid setItems(List items){ $fzaPD4.
this.items = items; R;j!}D!4
} e:5bzk!~
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publicint getPageSize(){ c`o7d)_Ke
return pageSize; }b-g*dn]5
} ~x|F)~:0=
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publicvoid setPageSize(int pageSize){ =17t-
[
this.pageSize = pageSize; *"{lMZ+
} C<P%CG&;
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publicint getTotalCount(){ 7:2WgLo
return totalCount; F~P%AjAx'
} 4 XAQVq5
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publicvoid setTotalCount(int totalCount){ D8xmE2%
if(totalCount > 0){ 1 A\OC
this.totalCount = totalCount; H(Z88.OM
int count = totalCount / 3h *!V6%q
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pageSize; /@,j232
if(totalCount % pageSize > 0) fc
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count++; aL&n[
indexes = newint[count]; o:_Xv.HRZo
for(int i = 0; i < count; i++){ W`u[h0\c
indexes = pageSize * fyByz=pl
j!7{|EQFcl
i; t$De/Uq
} ayfFVTy1d
}else{ +Nt2
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this.totalCount = 0; LRNh@g4ei
} 9;B0Mq
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} <x<"n t
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publicint[] getIndexes(){ 8]U{;|';
return indexes; RE/~#k@a
}
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publicvoid setIndexes(int[] indexes){ )s%[T-uKi
this.indexes = indexes; l\@)y4
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} ::}{_ Z
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publicint getStartIndex(){ FgB&b
return startIndex; [m|YWT=
} ~4 `5tb
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publicvoid setStartIndex(int startIndex){ j'HZ\_
if(totalCount <= 0) 70eb]\%
this.startIndex = 0; R~S;sJ& c
elseif(startIndex >= totalCount) Z\k&gio5C^
this.startIndex = indexes #6CC3TJ'k
/N&CaH\;^$
[indexes.length - 1]; C,NJb+J
elseif(startIndex < 0) /JWGifH
this.startIndex = 0; ybY]e; v*O
else{ ZOZ+ Y\uU
this.startIndex = indexes M)2VcDy
opc/e
[startIndex / pageSize]; ~NpA".PB
} A}3=561F?5
} 5nKj
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xo&]$W8
publicint getNextIndex(){
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int nextIndex = getStartIndex() + !Ikt '5/
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pageSize; hMykf4
if(nextIndex >= totalCount) v#U"pn|M
return getStartIndex(); 7G/1VeVjB
else Pc
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return nextIndex; E.Jkf\
} QmCe>+
n}!PO[m~
publicint getPreviousIndex(){ !& z(:d
int previousIndex = getStartIndex() - .MP !`
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pageSize; (A~/ '0/
if(previousIndex < 0) Z2'Bk2 L
return0; 4*Hgv:0?kI
else 0 g?z&?
return previousIndex; '|Kmq5)
} F*3j.lI
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} JYW)uJ
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抽象业务类 9Ru8~R/\
java代码: B4i!/@0s
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/** =9fajRFTt
* Created on 2005-7-12 f
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*/ ".<DAs j
package com.javaeye.common.business; 6{^E{go
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import java.io.Serializable; 5*,f
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import java.util.List; ;;:-l99
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import org.hibernate.Criteria; YTexv;VNb|
import org.hibernate.HibernateException; \l]DQaOEe
import org.hibernate.Session; tavpq.0O
import org.hibernate.criterion.DetachedCriteria; i03w1pSH,
import org.hibernate.criterion.Projections; rU2%dkTa
import K"4>DaK2P
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org.springframework.orm.hibernate3.HibernateCallback; D0%Ug>
import (K)] qNH
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org.springframework.orm.hibernate3.support.HibernateDaoS #]ypHVE
:n.f_v}6
upport; j]aoR
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import com.javaeye.common.util.PaginationSupport; to=y#$_
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public abstract class AbstractManager extends 4:dH]
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HibernateDaoSupport { "3)4vuX@;c
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privateboolean cacheQueries = false; XbD4:i%
^`)) C;
privateString queryCacheRegion; &iA?+kV
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publicvoid setCacheQueries(boolean RH O( ?8"_
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cacheQueries){ s0k`p<q
this.cacheQueries = cacheQueries; n1VaLD
} CB/D4j;
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publicvoid setQueryCacheRegion(String N#DYJ-~*
q(.:9A*0
queryCacheRegion){ b;cdIl!3
this.queryCacheRegion = C0}IE,]
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queryCacheRegion; -/ g B|J
} CJJzCVj
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publicvoid save(finalObject entity){ znaUB v_
getHibernateTemplate().save(entity); 8\5 T3AF
} b{]z
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publicvoid persist(finalObject entity){ ~XWQhIAM4
getHibernateTemplate().save(entity); .QN>z-YA6:
} \0vr>C
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publicvoid update(finalObject entity){ t-0a7
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getHibernateTemplate().update(entity); -<
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} L&%s[
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publicvoid delete(finalObject entity){ I.94v
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getHibernateTemplate().delete(entity); b7wvaRe.
} V&\[)D'c
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publicObject load(finalClass entity, h?8]C#6^
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finalSerializable id){ f^"N!f a
return getHibernateTemplate().load LkK~%tY
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(entity, id); '-"/ =j&d[
} A3iFI9Iv
}`,t$NV`
publicObject get(finalClass entity, K3x.RQQ-
5&q8g;XiEM
finalSerializable id){ yX0dbW~@y
return getHibernateTemplate().get 8W#heW\-]
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(entity, id); d
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} U2wbv Xr5-
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publicList findAll(finalClass entity){ nY`RRC
return getHibernateTemplate().find("from )Hk3A$6(
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" + entity.getName()); nw<&3k(g}
} y10h#&k
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publicList findByNamedQuery(finalString ?Vdia:
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namedQuery){ 0 SNIYkGE
return getHibernateTemplate (C@~3!AVa
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().findByNamedQuery(namedQuery); Hqn#yInA7~
} ~tR~?b T
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publicList findByNamedQuery(finalString query, j(k:
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finalObject parameter){ 0#S W!b|%
return getHibernateTemplate :C65-[PSdO
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().findByNamedQuery(query, parameter); `P3>S(Tgy
} ],JEBt
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publicList findByNamedQuery(finalString query, eZdu2.;<
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finalObject[] parameters){ =<X?sj5
return getHibernateTemplate .NvQm]N0.
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().findByNamedQuery(query, parameters); W034N[9
} |<.lW
NCk r /#!
publicList find(finalString query){ U]vYV
return getHibernateTemplate().find (v}>tb*#`
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(query); :h&fbBH
} kLni{IYN7
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publicList find(finalString query, finalObject $d)ca9
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parameter){ X'`~s}vGO
return getHibernateTemplate().find \7l-@6'7
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(query, parameter); mqAWL:VvQ7
} :xh?eN&
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public PaginationSupport findPageByCriteria &xY^OCt
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(final DetachedCriteria detachedCriteria){ i]|Yg$
return findPageByCriteria we;G]`@?
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); xgNJ eQ
} K,boVFs
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public PaginationSupport findPageByCriteria 8&3V#sn'
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(final DetachedCriteria detachedCriteria, finalint E gal4
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startIndex){ IuOgxm~Y
return findPageByCriteria bLQ ^fH4ww
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(detachedCriteria, PaginationSupport.PAGESIZE, `>?ra-
C0
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startIndex); Z6_N$Z.A
} G-He" 4& $
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public PaginationSupport findPageByCriteria '6xQT-sUih
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(final DetachedCriteria detachedCriteria, finalint ,>:;#2+og
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pageSize, 3'c0#h@VD
finalint startIndex){ GA?87N
return(PaginationSupport) H*Kj3NgY
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getHibernateTemplate().execute(new HibernateCallback(){ P~G 1EK|4
publicObject doInHibernate Fx
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(Session session)throws HibernateException { oA =4=`
Criteria criteria = +AHUp)
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detachedCriteria.getExecutableCriteria(session); <0QH<4
int totalCount = =ZDAeVz3w
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((Integer) criteria.setProjection(Projections.rowCount
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()).uniqueResult()).intValue(); +H9 >A0JF
criteria.setProjection "ajjJ"x A
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(null); 8g:;)u4$P
List items = T.We: ,{
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criteria.setFirstResult(startIndex).setMaxResults &g.+V/<[
1 29q`u;
(pageSize).list(); =9z[[dQ|L
PaginationSupport ps = e#Z$o($t
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new PaginationSupport(items, totalCount, pageSize, tX@_fYb
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startIndex); +> WM[o^I
return ps; AwTJJ0>
} \uXcLhXN
}, true); Z7_ zMM
} )E,\H@A
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public List findAllByCriteria(final rc/nFl6#
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[
DetachedCriteria detachedCriteria){ Ci<ATho
return(List) getHibernateTemplate rDQ!zlg>l
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().execute(new HibernateCallback(){ K)-m*#H&uw
publicObject doInHibernate B"v.*
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(Session session)throws HibernateException { nIoPC[%_
Criteria criteria = `8I&7c
un=2}@ '
detachedCriteria.getExecutableCriteria(session); Oer^Rk
return criteria.list(); .>mr%#p
} K\$J4~EtG
}, true); .{=$!8|&I9
} [<{Kw=X__2
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public int getCountByCriteria(final \N4
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DetachedCriteria detachedCriteria){ i-'9AYyw
Integer count = (Integer) :OkT? (i
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getHibernateTemplate().execute(new HibernateCallback(){ A5H3%o(6k
publicObject doInHibernate #fL8Kq
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(Session session)throws HibernateException { T<L^N+<,{N
Criteria criteria = Pf_S[
sm
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detachedCriteria.getExecutableCriteria(session); Y=
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return GHHav12][
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criteria.setProjection(Projections.rowCount TD9;kN1`
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()).uniqueResult(); MzP7Py
8.
} OZIW_'Wm/
}, true); 3 HIz9F(
return count.intValue(); Rt{B(L.?<
} oh
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} (C\hVy2X?N
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aj"M>zd*}
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用户在web层构造查询条件detachedCriteria,和可选的 4WN3=B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 R-RDT9&<
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PaginationSupport的实例ps。 3"kdjOB
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ps.getItems()得到已分页好的结果集 `iJhG^w9M
ps.getIndexes()得到分页索引的数组 fsEzpUY:{W
ps.getTotalCount()得到总结果数 h@@nR(<i
ps.getStartIndex()当前分页索引 eXkujjSw"
ps.getNextIndex()下一页索引 Sje wuIi1
ps.getPreviousIndex()上一页索引 JIFU;*PR1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 78Aa|AJU
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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 {\z({Wlb]
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一下代码重构了。 'r@:Cz3e*I
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我把原本我的做法也提供出来供大家讨论吧: 8:o<ry
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首先,为了实现分页查询,我封装了一个Page类: +hRmO
java代码: c=[O
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/*Created on 2005-4-14*/ x%<
package org.flyware.util.page; =B ];?%
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/** (Si=m;g
* @author Joa .,i(2^
* *1'`"D~
*/ jV/CQM5a+
publicclass Page { >;#=gM
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/** imply if the page has previous page */ J j=;
privateboolean hasPrePage; WA$>pG5s
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/** imply if the page has next page */ CAU0)=M
privateboolean hasNextPage; 0vGyI>
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/** the number of every page */ ^Q{Bq
privateint everyPage; H3H_u4_?SE
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/** the total page number */ NJ MJ
privateint totalPage; ai'4_
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/** the number of current page */ <N(oDa U
privateint currentPage; Gs*G<P"
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/** the begin index of the records by the current #Ch;0UvFF
3:5DL!Sm8J
query */ ow/57P
privateint beginIndex; XYH|;P6K
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/** The default constructor */ phYDs9-K
public Page(){ /U$8TT8+-
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} 5y}
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/** construct the page by everyPage 0fs$#j
* @param everyPage >qo~d?+
* */ 7yt=]1
public Page(int everyPage){ hKlZi!4J
this.everyPage = everyPage; ` r']^
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} Ao7 `G':
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/** The whole constructor */ GOSI3RRn
public Page(boolean hasPrePage, boolean hasNextPage, 3I|3wQ (
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int everyPage, int totalPage, FZH\Q~IUV
int currentPage, int beginIndex){ Bd3~E bFL
this.hasPrePage = hasPrePage; xAwf49N~
this.hasNextPage = hasNextPage; [`Cq\mI-W
this.everyPage = everyPage; up%Z$"Y
this.totalPage = totalPage; l+y}4k=/
this.currentPage = currentPage; }E}8_8T6
this.beginIndex = beginIndex; jko"MfJ
} 2uk x (Z
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/** [<wbbvXR
* @return RiO="tX'
* Returns the beginIndex. E4D (,s
*/ ~SjZk|
publicint getBeginIndex(){ nMoWOP'
return beginIndex; pGIe=Um0W
} [rreFSy#@
h7;bclU
/** ]$M<]w,IJ2
* @param beginIndex cUK\x2
* The beginIndex to set. bO<0qM~
*/ S^cH}-+
publicvoid setBeginIndex(int beginIndex){ }wSy
this.beginIndex = beginIndex; 0ZC,BS`D^
} uu%?K@Qq
#^&jW
/** WjM>kWv
* @return \h3e-)
* Returns the currentPage. z]Acs
*/ (_9|w|(
publicint getCurrentPage(){ =!ac7i\F
return currentPage; f]d!hz!
} Jbp5'e
_
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/** y~F<9;$=
* @param currentPage ^GYq#q9Q
* The currentPage to set. TK>{qxt:=
*/ @ERu>nSP
publicvoid setCurrentPage(int currentPage){ )Hf~d=GG
this.currentPage = currentPage; >WM3|
} .}9FEn 8
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/** 1.R
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* @return X^< >6|)
* Returns the everyPage. GJ}.\EaAJ
*/ w}M3x^9@
publicint getEveryPage(){ ^C9x.4I$)
return everyPage; G5{Ot>;*%
} [BBpQN.^q6
(3md:r<-
/** P 4;{jG
* @param everyPage &.*uc|{
* The everyPage to set. B50 [O!
*/ 7CrpUh
publicvoid setEveryPage(int everyPage){ o@dy:AR
this.everyPage = everyPage; 5a(<%Q
<"
} CtT~0Y|
;o$;Z4:.D
/** MB*u-N0v
* @return 4^Ow^7N?
* Returns the hasNextPage. GM}C]MVD
*/ v3JPE])/
publicboolean getHasNextPage(){
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return hasNextPage; lug}
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} +$(0w35V5
)o8g=7Jm
/** ">6&+^BN'
* @param hasNextPage *?8RXer
* The hasNextPage to set. )&.!3y 660
*/ j
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publicvoid setHasNextPage(boolean hasNextPage){ +AK:(r
this.hasNextPage = hasNextPage; /84bv=
} <pOl[5v]
*fP(6e#G,
/** >QI~`MiI
* @return .v,bXU$@YG
* Returns the hasPrePage. iMWW%@U^=
*/ )
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publicboolean getHasPrePage(){ G\1J _al
return hasPrePage; Lh 9S8EU
} d,R6` i
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/** y`b\;kd
* @param hasPrePage vbKQ*
* The hasPrePage to set. G&o64W;-s
*/ z{6YC~
publicvoid setHasPrePage(boolean hasPrePage){ k_Tswf3
this.hasPrePage = hasPrePage; <bdyAUeFw
} 9d"5wx
l^,qO3ES
/** aRKv+{K
* @return Returns the totalPage. k
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* ?
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*/ H'h#wV`(
publicint getTotalPage(){ Q>IH``1*e
return totalPage; ih!~G5Xi9i
}
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/** QUPf*3Oy
* @param totalPage C<t RU5|
* The totalPage to set. ,xj3w#`zaf
*/ vfXJYw+6_
publicvoid setTotalPage(int totalPage){ n{{P3f
this.totalPage = totalPage; }Z-I2
=]
} taCCw2s-8*
/:Y9sz uW`
} F;a3
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i>"dBJh]b
DoG%T(M!a9
,F}r@
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
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个PageUtil,负责对Page对象进行构造: +@>:%yX
java代码: Tc,$TCF
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K6(.KEW
/*Created on 2005-4-14*/ qwP $~Bj
package org.flyware.util.page; &>V/X{>$`K
8{@`kyy|
import org.apache.commons.logging.Log; IM$0#2\
import org.apache.commons.logging.LogFactory; j=Q$K#sBt
od(:Y(4
/** aG
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* @author Joa :p&IX"Hh
* <c\]Ct
*/ NGj"ByVjx
publicclass PageUtil { [Gf{f\O
fwH`}<o
privatestaticfinal Log logger = LogFactory.getLog ?k::tNv0
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(PageUtil.class); (s Jq;Z
>3+FZ@.iT
/** V*~423
* Use the origin page to create a new page X/wmKi
* @param page C{)HlOW
* @param totalRecords FbBX}n
* @return \KNdZC?V2
*/ Uf^RLdoDn
publicstatic Page createPage(Page page, int ,,}sK
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totalRecords){ s~)L_ p
return createPage(page.getEveryPage(), f^u^-l
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page.getCurrentPage(), totalRecords);
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} ~z>BfL
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/** i[8NO$tN1)
* the basic page utils not including exception v#-E~;CcC
@?Fx
handler s1Okoxh/!V
* @param everyPage %Dra7B%
* @param currentPage n3*UgNg%fK
* @param totalRecords ;n`
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* @return page pY,O_
t$
*/ ?-d
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publicstatic Page createPage(int everyPage, int QQT G9s
srsK:%`
currentPage, int totalRecords){ @7 )Z
everyPage = getEveryPage(everyPage); u2\+?`Ox
currentPage = getCurrentPage(currentPage); s><IykIi
int beginIndex = getBeginIndex(everyPage, ?LR"hZ>
6 1L7
-~
currentPage); VkWO}
int totalPage = getTotalPage(everyPage, ]u;GNz}?
90?,-6
totalRecords); V8\$`NEP
boolean hasNextPage = hasNextPage(currentPage, m:b^,2"g
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totalPage); (lieiye^
boolean hasPrePage = hasPrePage(currentPage); mZ~mf->%
2|$lk8 /,
returnnew Page(hasPrePage, hasNextPage, ,zG <7~m
everyPage, totalPage, 8znj~7}#
currentPage, A"0wvk)UcY
J
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beginIndex); _IC,9bbg
} 'xQna+ %h
K/Sq2:
privatestaticint getEveryPage(int everyPage){ sE-x"c
return everyPage == 0 ? 10 : everyPage; xcw%RUC-
} 9^(HXH_f
Y:rJK|m
privatestaticint getCurrentPage(int currentPage){ NoJUx['6
return currentPage == 0 ? 1 : currentPage; I Jqv w
} BSOjyy1f
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privatestaticint getBeginIndex(int everyPage, int B'<!k7Ewy
NP$e-" 1
currentPage){ *&(2`#C;
return(currentPage - 1) * everyPage; @X
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} Go-wAJ>
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privatestaticint getTotalPage(int everyPage, int wH+FFXGJs
4=~ 9v
totalRecords){ W)|c[Q\
int totalPage = 0; t3pZjdLJd
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if(totalRecords % everyPage == 0) (QhGxuC
totalPage = totalRecords / everyPage;
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else /3OC7!~;fM
totalPage = totalRecords / everyPage + 1 ; 7WgIhQ~
n?zbUA#
return totalPage; $Z,i|K;
} 3fm;r5
'`9%'f)
privatestaticboolean hasPrePage(int currentPage){ -l\~p4U
return currentPage == 1 ? false : true; g[m3IJzq
} -,FK{[h]ka
6 #-6Bh)>4
privatestaticboolean hasNextPage(int currentPage, u)tHOV>&
N[0
xqQ
int totalPage){ a3Z:C!|O'
return currentPage == totalPage || totalPage == mYiSR
UaH26fWs
0 ? false : true; lTxY6vi
} @c6"RHG9
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rny@n^F
} q1U&vZ3]c
i:V0fBR[>
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 kX@bv"i
K~`n}_:
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 jK\V|5k
"}0)YRz%
做法如下: +R2^*
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1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a];BW)
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的信息,和一个结果集List: u(8 _[/_B
java代码: nu;}S!J
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#S@UTJa
/*Created on 2005-6-13*/ )`B
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package com.adt.bo; -Pqi1pj]
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import java.util.List; <^CYxy
R#"U/8b>z
import org.flyware.util.page.Page; %T`4!:vy
q:TZ=bs^
/** fn1 ?Qp|
* @author Joa
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*/ tn"Y9
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publicclass Result { ATKYjhc _
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private Page page; "}S9`-Wd|
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private List content; aEcktg6h
r{pI-$
/** aeG#:
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* The default constructor ML=hKwCA
*/ 9
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public Result(){ t7{L[C$
super(); K)yCrEZ
} "WF(
6z#
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/** l@,); w=_P
* The constructor using fields B] A 5n8<
* Z_iAn TT
* @param page Iq4 Kgc
* @param content s5c! ^,L8
*/ N,WI{*
public Result(Page page, List content){ D< nlb-
this.page = page; DZHrR:q?e
this.content = content; t`
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} 9F2w.(m
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/** LVPt*S= /
* @return Returns the content. ke3HK9P;
*/ - XE79 fQ
publicList getContent(){ /2g)Z!&+L
return content; xT_fr,P
} .yctE:n
^/`#9]<%
/** PphR4 sIM
* @return Returns the page. Eg@R[ ^T
*/ =$"zqa.B6
public Page getPage(){ opUKrB
return page; `A4QU,0
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} Bg+<*z-?e
y)?W-5zL
/** N&0uXrw
* @param content O ,Pl7x%tK
* The content to set. F<PWBs%
*/ )'BJ4[aq\
public void setContent(List content){ Ee t+
this.content = content; MZUF! B
} pm'@2dT
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/** hRuo,FS#:
* @param page !.;xt L
* The page to set. AmT|%j&3
*/ H j5WJ{p.
publicvoid setPage(Page page){ 4
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this.page = page; Vu|Br
} -V;0_Nx7p
} )8 "EI-/.
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Pe+ 8~0o=R
U /1[~429
mV:RmA
2. 编写业务逻辑接口,并实现它(UserManager, Q|j@#@O 1
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UserManagerImpl) F:*[
java代码: LyJTK1]#
a@5xz)
877EKvsiC
/*Created on 2005-7-15*/ q
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package com.adt.service; j=xtnIq
@\%)'WU
import net.sf.hibernate.HibernateException; 3PvZ_!G
P`Hd*xh".j
import org.flyware.util.page.Page; _V_8p)%
a'_MhJ zs
import com.adt.bo.Result; \p>]G[g
Y^c,mK^
/** X] JpS
* @author Joa `mq4WXO\
*/ _e:5XQ
publicinterface UserManager { ?RRSrr1
e6{[o@aM{
public Result listUser(Page page)throws \J,- <wF
xY\*L:TwW
HibernateException; wZ]BY;
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} uhC=
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u/!mN2{Rd
~`G;=ITo
java代码: K\^&_#MG
9z|>roNe
L6[rvM|9_
/*Created on 2005-7-15*/ L5zG0mC8
package com.adt.service.impl; rx}ujjx
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import java.util.List; \4\\575zp'
fncwe ';?
import net.sf.hibernate.HibernateException; FfD
,cDs
qSpa4W[
import org.flyware.util.page.Page; +c]N]?k&
import org.flyware.util.page.PageUtil; JL.ydH79
(:fE _H2z
import com.adt.bo.Result; z~}StCH(
import com.adt.dao.UserDAO; 7+D'W7Yx
import com.adt.exception.ObjectNotFoundException; j^aQ>(t(9
import com.adt.service.UserManager; D)O6|DiO
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/** _ pH6uuB
* @author Joa skR,M=F~
*/ 9aF..
publicclass UserManagerImpl implements UserManager { :b M$;
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private UserDAO userDAO; 80 s~ae;
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/** So)KI_M
* @param userDAO The userDAO to set. (v'lb!j^#
*/ _Y
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publicvoid setUserDAO(UserDAO userDAO){ 0'\FrG
this.userDAO = userDAO; [KimY
} PO%yWns30o
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/* (non-Javadoc) t'=~"?T/o
* @see com.adt.service.UserManager#listUser '.h/Y/oz
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(org.flyware.util.page.Page) f1]AfH#
*/ {M)3GsP?
public Result listUser(Page page)throws A=qW]Im
3'sWlhf;
HibernateException, ObjectNotFoundException { Ghq'k:K,
int totalRecords = userDAO.getUserCount(); 2=Y_Qrhi
if(totalRecords == 0) \6`%NhkM_
throw new ObjectNotFoundException ?2<6#>(7a
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("userNotExist"); Gh gvRR$
page = PageUtil.createPage(page, totalRecords); St7D.|
List users = userDAO.getUserByPage(page); 1)/T.q<D"
returnnew Result(page, users); ktw!T{
} tZNad
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} 2ucF(^
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}*}`)rj,
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 L>5!3b=b
K&D}!.~/
询,接下来编写UserDAO的代码: soqNzdTB2
3. UserDAO 和 UserDAOImpl: Y8`))MeD
java代码: ZTBFV/{
E!}-qbH^
WW\)B-}T
/*Created on 2005-7-15*/ dnX`F5zd
package com.adt.dao; ,[ J'!NC1
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import java.util.List; H8t{ >C)]
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import org.flyware.util.page.Page; Y3MR:{}
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import net.sf.hibernate.HibernateException; &W!d}, ;
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/** ^d5./M8Bd
* @author Joa 7].IT(
*/ 3 ?|; on
publicinterface UserDAO extends BaseDAO { <0Egkz3s
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publicList getUserByName(String name)throws Acq>M^E3
^0ZKHR(}e
HibernateException; j=jrzG+`
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publicint getUserCount()throws HibernateException; eR*
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publicList getUserByPage(Page page)throws dW^_tzfF7
$L#Z?76v
HibernateException; w7t"&=pF7
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} dI0>m:RBz
9y|&T
Fx88R!
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jVFRq T%
java代码: HH~
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Ye=7Y57Nr
/*Created on 2005-7-15*/ |7Xpb
package com.adt.dao.impl; u FYQ^
#<i><EG
import java.util.List; .McoW7|Y
Lc: SqF
import org.flyware.util.page.Page; hIO4%RQj_
vzrD"
import net.sf.hibernate.HibernateException; q(ET)xCeD
import net.sf.hibernate.Query; pffw5Tc
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import com.adt.dao.UserDAO; %J (
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b} U&bFl
/** 9Or4`JOO
* @author Joa )Q
*/ m2<
*
public class UserDAOImpl extends BaseDAOHibernateImpl soVZz3F
teS0F
implements UserDAO { eGypXf%
R
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/* (non-Javadoc) y[@j0xlO
* @see com.adt.dao.UserDAO#getUserByName twHM~cTS
~S=fMv^BR
(java.lang.String) [@)z $W
*/ gJFpEA {
publicList getUserByName(String name)throws wZ3vF)2s
=#")G1A
HibernateException { k-DB~-L
String querySentence = "FROM user in class `# M.t);^
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com.adt.po.User WHERE user.name=:name"; ;7`um
Query query = getSession().createQuery rRG\:<a
K#C56k q&
(querySentence); D*r Zaqy
query.setParameter("name", name); t?H;iBrpxd
return query.list(); nTy,Jml
} Qbt>}?-
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/* (non-Javadoc) rKs WS~U
* @see com.adt.dao.UserDAO#getUserCount() ?O>JtEz~lQ
*/ U W)&Eky
publicint getUserCount()throws HibernateException { FjLv*K[#d
int count = 0; 5<BV\'
String querySentence = "SELECT count(*) FROM E4aCGg
'W2$wN+P
user in class com.adt.po.User"; TNT"2FoBd
Query query = getSession().createQuery GKx,6E#JM
@P5@&G
(querySentence); VJtTbt;>
count = ((Integer)query.iterate().next <9.7 gwzE
~rJw$v
()).intValue(); otH[?c?BT
return count; Q2pboZ86
} EC!Cv;'
k|c0tvp
/* (non-Javadoc) YGpp:8pen
* @see com.adt.dao.UserDAO#getUserByPage x7kg_`\U
Jq<`j<'9
(org.flyware.util.page.Page) u.4vp]eU
*/ `1}?{ud
publicList getUserByPage(Page page)throws `iayh
wOkJ:k
HibernateException { l=?y=2+
String querySentence = "FROM user in class =2)$|KC
/(pD^D
com.adt.po.User"; IoHkcP[H
Query query = getSession().createQuery }%d-U;Tt2
tBI+uu aa2
(querySentence); s=Q*|
query.setFirstResult(page.getBeginIndex()) !E#.WX
.setMaxResults(page.getEveryPage()); =RE_Urt:
return query.list(); c7Qa !w
} Mciq9{8&