Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 %ERcFI]G
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 CC`_e^~y=F
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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 kygw}|, N
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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 i#`q<+/q
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分页支持类: Q7$o&N{
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java代码: VE|l;aXi
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package com.javaeye.common.util; fx{8ERo
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import java.util.List; *(F`NJ 3
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publicclass PaginationSupport { mOsp~|d
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publicfinalstaticint PAGESIZE = 30; gVOAB-nw
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privateint pageSize = PAGESIZE; 4\Y5RfLB_
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privateList items; "^n,(l*4x
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privateint totalCount; Zp9.
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privateint[] indexes = newint[0]; Dp
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privateint startIndex = 0; S=(O6+U
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public PaginationSupport(List items, int Go)$LC0Mi
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totalCount){ k||t<&`Ze
setPageSize(PAGESIZE); -Lh7!d
setTotalCount(totalCount); 3N2dV6u
setItems(items); :hX[8u
setStartIndex(0); qq| 5[I.?
} ukW&\
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public PaginationSupport(List items, int 9Rnypzds
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totalCount, int startIndex){ 6QX m]<
setPageSize(PAGESIZE); `OBzOM
setTotalCount(totalCount); ?dgyi4J?=`
setItems(items); Q!e560@
setStartIndex(startIndex); 20;9XJmjl
} `r`8N6NQ&]
}'$PYAf6
public PaginationSupport(List items, int KhHFJo[8sf
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totalCount, int pageSize, int startIndex){ 8s0+6{vW
setPageSize(pageSize); <W"W13*j!
setTotalCount(totalCount); O,Q.-
setItems(items); br[iRda@
setStartIndex(startIndex); ^}_Ka //k
} t;e&[eg
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publicList getItems(){ lM6pYYEq=
return items; Gmz^vpQ]t
} 0@
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publicvoid setItems(List items){ i+*!"/De
this.items = items; P=QxfX0B
}
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publicint getPageSize(){ kJWg},-\
return pageSize; Hc)z:x;Sj
} {{?g%mQ6
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publicvoid setPageSize(int pageSize){ 2?JV "O=
this.pageSize = pageSize; Lgg,K//g
}
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publicint getTotalCount(){ L8VOiK=,
return totalCount; ;o_F<68QP
} !(GyOAb
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publicvoid setTotalCount(int totalCount){ Y}:~6`-jj
if(totalCount > 0){ k{}> *pCU
this.totalCount = totalCount; gxv^=;2C
int count = totalCount / m\L`$=eO8
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pageSize; 3e_tT8
if(totalCount % pageSize > 0) /Nf{;G!kg
count++; ;w7 mr1
indexes = newint[count]; y6XOq>
for(int i = 0; i < count; i++){ WAa45G
indexes = pageSize * B*(]T|ff<
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i; 53HA6:Q[
} [FO4x`
}else{ c|&3e84U
this.totalCount = 0; 7n8nJTU{4j
} ^3;B4tj[
} QNj]wm=mp
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publicint[] getIndexes(){ (Rw<1q`,
return indexes; KGz Nj%
}
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publicvoid setIndexes(int[] indexes){ *]$B 9zVs!
this.indexes = indexes; v"USD<
} )9]a
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publicint getStartIndex(){ [C'bfX5HB5
return startIndex; n|( lPbD
} m=dNJF
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publicvoid setStartIndex(int startIndex){ 9`tK9
if(totalCount <= 0) B~p%pTS+
this.startIndex = 0; !J$r|IX5
elseif(startIndex >= totalCount) k^J8 p#`6
this.startIndex = indexes 8<=^Rkz
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[indexes.length - 1]; i?x gV_q;
elseif(startIndex < 0) "tJ+v*E
this.startIndex = 0; I|Oco?Q"
else{ }Q\%tZC#T
this.startIndex = indexes #-/W?kD
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[startIndex / pageSize]; 5S~ H[>A"
} z$~x 2<
} a3@E`Z
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publicint getNextIndex(){ 7EJ2 On
int nextIndex = getStartIndex() + PTQ#8(_,
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pageSize; hlzB
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if(nextIndex >= totalCount) ]3KeAJ
return getStartIndex(); C/kf?:j
else ~iL^KeAp
return nextIndex; uo9#(6
} h0{X$&:
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publicint getPreviousIndex(){ F.9}jd{
int previousIndex = getStartIndex() - hZ&KE78?
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pageSize; iC"iR\Qu
if(previousIndex < 0) rB>ge]$.
return0; >!963>D R
else n;g'?z=hy
return previousIndex;
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} CIudtY(:
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} 8wU$kK
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抽象业务类 ,81%8r
java代码: vy<W4
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/** w"hd_8cO
* Created on 2005-7-12 BU`X_Z1)
*/ -f+#j=FX
package com.javaeye.common.business; odv2 (\
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import java.io.Serializable; kDmm
import java.util.List; R9XU 7_3B
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import org.hibernate.Criteria; YQMWhC,8hy
import org.hibernate.HibernateException; ^Q/*on;A,/
import org.hibernate.Session; [+ud7l
import org.hibernate.criterion.DetachedCriteria; $8tk|uh
import org.hibernate.criterion.Projections; D"7}&Ry:
import 55S s%$k@
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org.springframework.orm.hibernate3.HibernateCallback; 9LR=>@Z
import C6!F6Stn]g
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org.springframework.orm.hibernate3.support.HibernateDaoS JZ5k3#@e
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upport; O]N /(pe:d
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import com.javaeye.common.util.PaginationSupport; Y_Yf'z1>[
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public abstract class AbstractManager extends AwM`[`ReE
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HibernateDaoSupport { 5pQpzn=
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privateboolean cacheQueries = false; fzsy<Vl",
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privateString queryCacheRegion; VotC YJ
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publicvoid setCacheQueries(boolean \!u<)kkyT
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cacheQueries){ -TUJ"ep]QJ
this.cacheQueries = cacheQueries; 6VW*8~~Xy
} ZW4f "
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publicvoid setQueryCacheRegion(String 8^7Oc,:~
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queryCacheRegion){ 09kR2(nsW/
this.queryCacheRegion = ww2mL
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queryCacheRegion; > 0^<<=m
} '|8dt "C
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publicvoid save(finalObject entity){ : auR0FE
getHibernateTemplate().save(entity); uwwR$
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} ;[ <(4v$
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publicvoid persist(finalObject entity){ `YhGd?uu$
getHibernateTemplate().save(entity); T#!>mL|9|
} d |17G
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publicvoid update(finalObject entity){ Xu$>$D#a
getHibernateTemplate().update(entity); wZvv5:jKpu
} -Vn#Ab_C
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publicvoid delete(finalObject entity){ &Ok1j0~~
getHibernateTemplate().delete(entity); #asg5 }
} qC`}vr|Z
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publicObject load(finalClass entity, s.J4&2Q
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finalSerializable id){ 80lei
return getHibernateTemplate().load '*J+mZt N
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(entity, id); J0xHpe
}
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publicObject get(finalClass entity, ;;0'BdsL`
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finalSerializable id){ {npm9w<;
return getHibernateTemplate().get :=Olp;+_
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(entity, id); :ld~9
} VLuHuih
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publicList findAll(finalClass entity){ s9Hxiw@D
return getHibernateTemplate().find("from D<WnPLA$g
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" + entity.getName()); l5 9a3=q
} F0$w9p
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publicList findByNamedQuery(finalString Fp\;j\pfw
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namedQuery){ VN`.*B|9[
return getHibernateTemplate 2KLMFI.F
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().findByNamedQuery(namedQuery); @KQ>DBWQM
} EI_-5Tt RD
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publicList findByNamedQuery(finalString query, mnm
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finalObject parameter){ )eZK/>L&
return getHibernateTemplate ocGrB)7eD
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().findByNamedQuery(query, parameter); H/o_? qK
} >@vu;j\*E5
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publicList findByNamedQuery(finalString query, u8-6s+
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finalObject[] parameters){ gUklP(T=u
return getHibernateTemplate $Q*R/MY
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().findByNamedQuery(query, parameters); sVHF\{<
} P< OH{l
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publicList find(finalString query){ 2!#g\"
return getHibernateTemplate().find #^}H)>jWy
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(query); /4x\}qvU
} [F6)Z[uG
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publicList find(finalString query, finalObject En\@d@j<u
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parameter){ ;,77|]<XE
return getHibernateTemplate().find T]th3*
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(query, parameter); 78l);/E{v
} p%DU1+SA
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public PaginationSupport findPageByCriteria o`YBz~2
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(final DetachedCriteria detachedCriteria){ u}du@Aq
return findPageByCriteria 5*44QV
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); m.lR]!Y=w
} oJa}NH
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public PaginationSupport findPageByCriteria 505c(+
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(final DetachedCriteria detachedCriteria, finalint NjIPHM$g
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startIndex){ B $u/n
return findPageByCriteria _=HaE&
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(detachedCriteria, PaginationSupport.PAGESIZE, ~Dt$}l-9
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startIndex); m7^f%<l
} ,5W7a
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public PaginationSupport findPageByCriteria 4X^$"lM
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(final DetachedCriteria detachedCriteria, finalint (\ab%M
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pageSize, l8G1N[
finalint startIndex){ k]p|kutQCy
return(PaginationSupport) jSjC43lh
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getHibernateTemplate().execute(new HibernateCallback(){ t?"(Zb
publicObject doInHibernate r^5%0_F]
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(Session session)throws HibernateException { |%|03}Q
Criteria criteria = p_I^7 $
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detachedCriteria.getExecutableCriteria(session); ,sitO y}ks
int totalCount = o< @![P
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((Integer) criteria.setProjection(Projections.rowCount @ki|#ro
(
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()).uniqueResult()).intValue(); xt|^~~ /
criteria.setProjection -=5~h
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(null); q8P&rMwy
List items = CHGa_
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criteria.setFirstResult(startIndex).setMaxResults SnG(/1C8
+&S7l%-
(pageSize).list(); @ujwN([I
PaginationSupport ps = Nvd(?+c
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new PaginationSupport(items, totalCount, pageSize, >@7$=Y>D
'>
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startIndex); P")I)>Q6
return ps; t*hy"e{*a
} \
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}, true); QF/ULW0G!
} <|l}@\iRX
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public List findAllByCriteria(final uE.BB#
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DetachedCriteria detachedCriteria){ Z3&}C h
return(List) getHibernateTemplate wp@_4Iq1$
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().execute(new HibernateCallback(){ 9s<4`oa
publicObject doInHibernate Cn/WNCzst&
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(Session session)throws HibernateException { 1
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Criteria criteria = lU doMm
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detachedCriteria.getExecutableCriteria(session); ]A2E2~~G
return criteria.list(); B>nj{W<o
} X$5
}, true); (
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} /<) Vd
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public int getCountByCriteria(final j{lurb)y
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DetachedCriteria detachedCriteria){ "}v.>L<P
Integer count = (Integer) 5QiQDQT}5
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate 2VRGTx
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(Session session)throws HibernateException { b*Y Wd3
Criteria criteria = @Fc:9a@
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detachedCriteria.getExecutableCriteria(session); @dv8 F
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return ?JZ$M
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criteria.setProjection(Projections.rowCount b$klm6nMvm
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()).uniqueResult(); P7F"#R0QB
} kBZ1)?
}, true); Q3WI@4
return count.intValue(); zjA]Tr
} by<@\n2B:U
} ir<e^a
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用户在web层构造查询条件detachedCriteria,和可选的 b7>'ARdbzX
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 XHU$&t`7>g
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PaginationSupport的实例ps。 Ms|c"?se
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ps.getItems()得到已分页好的结果集 bVzi^R"
ps.getIndexes()得到分页索引的数组 }O*`I(
ps.getTotalCount()得到总结果数 @?<[//1
ps.getStartIndex()当前分页索引 T)gulP
ps.getNextIndex()下一页索引 KFbB}oId
ps.getPreviousIndex()上一页索引 3'.@aMA@
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 kY$EK]s
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 44}5o
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一下代码重构了。 y;ElSt;S
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我把原本我的做法也提供出来供大家讨论吧: nmU1xv_
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首先,为了实现分页查询,我封装了一个Page类: D[yyFo,z
java代码: WrGA7&!+
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/*Created on 2005-4-14*/ @N4~|`?U
package org.flyware.util.page; .v+JV6!u
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/** ZwDL
* @author Joa lfj5?y
* OL
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*/ fF)Q;~_VA
publicclass Page { bKpy?5&>
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/** imply if the page has previous page */ cp@Fj"
privateboolean hasPrePage; 2Xl+}M.:Y
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/** imply if the page has next page */ hty'L61\z
privateboolean hasNextPage; B4b'0p
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/** the number of every page */ z&gmaYwq
privateint everyPage; (S!UnBb&
`2 <:$]
/** the total page number */ itzUq,T
privateint totalPage; FC1rwXL(
jUm-!SK}q
/** the number of current page */ .rK0C)
privateint currentPage; geR
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/** the begin index of the records by the current E /H%q|q
K} CgFBk
query */ ? uYO]!VC
privateint beginIndex; <uuumi-!%G
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/** The default constructor */ 6RbDc*
public Page(){ Qbv@}[f
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} \< .BN;t{
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/** construct the page by everyPage ;3/}"yG<p
* @param everyPage ^i8,9T'=
* */ q8$t4_pF
public Page(int everyPage){ NAD^10
this.everyPage = everyPage; ~5HT_B U=
} y8$3kXh
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/** The whole constructor */ t+KW=eW
public Page(boolean hasPrePage, boolean hasNextPage, %!\=$ s}g
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int everyPage, int totalPage, Ln#o:" E
int currentPage, int beginIndex){ 6!]@S|vDX
this.hasPrePage = hasPrePage; -4x! #|]
this.hasNextPage = hasNextPage; &`qYe)1Eo
this.everyPage = everyPage; TAUl{??,
this.totalPage = totalPage; 4+hNP'e
this.currentPage = currentPage; g!~SHW)l
this.beginIndex = beginIndex; -
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} =Q9^|& 6
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/** '^)'q\v'k
* @return sc]#T)xG
* Returns the beginIndex. qefp3&ls
*/ Gt*<Awn8
publicint getBeginIndex(){ :z8/iD y
return beginIndex; >3/mV<g f
} 'f{13-#X@
q(qm3OxYo
/** c= t4 gf
* @param beginIndex c6F?#@?
* The beginIndex to set. }p?,J8=-
*/ l?)>"^
publicvoid setBeginIndex(int beginIndex){ Wq3PN^
this.beginIndex = beginIndex; h^(U:M=A
} T)e2IXGN
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/** (/uN+
* @return H}r]j\
* Returns the currentPage. &Z~_BT
*/ U1:m=!S;x
publicint getCurrentPage(){ G
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return currentPage; |y7TYjg6
} M<Bo<,!ua
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/** S!A:/(^WB
* @param currentPage @2"uJ6o
* The currentPage to set. Ct `)R
*/ #v(As)4^
publicvoid setCurrentPage(int currentPage){ DTC
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this.currentPage = currentPage; {qHQ_ _Bl
} YQD`4ND
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/** HBp??.r
* @return _kBmKE
* Returns the everyPage. n}Z%-w$K#
*/ P\dfxR;8%
publicint getEveryPage(){ BW;@Gq@N
return everyPage; pbG-uH^
} N|mggz
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/** J <z
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* @param everyPage 5:38}p9`
* The everyPage to set. 7d.H8C2
*/ $E[O}+L$#
publicvoid setEveryPage(int everyPage){ O_ r-(wE4
this.everyPage = everyPage; d1#lC*.Sg
} cWnEp';.
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/** rWWpP<
* @return "zw{m+7f,
* Returns the hasNextPage. ]iTP5~8U
*/ O)^F z:
publicboolean getHasNextPage(){ kR1
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return hasNextPage; ]foS.D,
} Z<|x6%
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/** 1?)h-aN
* @param hasNextPage Ew]&~:$Ki
* The hasNextPage to set. LntRLB'
*/ '\QJ{/JV
publicvoid setHasNextPage(boolean hasNextPage){ :JBtqpo2
this.hasNextPage = hasNextPage; MA{ZmPm)
} I[A<e]uK
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/** >Ch2Ep
* @return PM@_ZJ'x
* Returns the hasPrePage. lrPIXIM
*/ NfQQJ@*
publicboolean getHasPrePage(){ 6-$95.Y2
return hasPrePage; s-6$C
} L7lpOy4k
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/** uWMSn
* @param hasPrePage .HTRvE`X
* The hasPrePage to set. k_1;YOBF
*/ BV<_1WT}
publicvoid setHasPrePage(boolean hasPrePage){ Foj|1zJS_
this.hasPrePage = hasPrePage; CNV^,`FX
} {y{O ze
b!-=L&V
/** xGOmvn^lQ
* @return Returns the totalPage. v#9i|
* "&qAV'U
*/ w[vccARQ
publicint getTotalPage(){ k0FAI0~(
return totalPage; E}zGY2Xx
} ]/p>p3@1C
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/** ENA"T-p
* @param totalPage w}/+3z
* The totalPage to set. h+_:zWU
*/ >t9DI
publicvoid setTotalPage(int totalPage){ 2ETv H~23
this.totalPage = totalPage; MYJMZ3qBi
} ?W dY{;&
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} ~mHrgxQ-
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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 `o{_+Li9
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个PageUtil,负责对Page对象进行构造: oG hMO
java代码: 1LSD,t|
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/*Created on 2005-4-14*/ lQgavP W!
package org.flyware.util.page; 2.{zfr
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import org.apache.commons.logging.Log; u!HbS*jqq
import org.apache.commons.logging.LogFactory; :v45Ls4J
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/** ^;{uop"DS
* @author Joa Y#P!<Q>}
* P=P']\`p+
*/ ~USyN'5lU7
publicclass PageUtil { 0e:j=kd)NH
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privatestaticfinal Log logger = LogFactory.getLog c<Ud[x.
1JOoICjB
(PageUtil.class); >`yRL[c;
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/** $E8}||d
* Use the origin page to create a new page C%%gCPI^y
* @param page sA+K?_
* @param totalRecords +~1FKLu
* @return A58P$#)?
*/ IW}Wt{'m
publicstatic Page createPage(Page page, int @eESKg(,
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totalRecords){ .Y!dO@$:
return createPage(page.getEveryPage(), ]R^xO;g'
1;,<UHF8N
page.getCurrentPage(), totalRecords); N3)n**
} d|gfp:Z`a
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/** SpIiMu(
* the basic page utils not including exception |g!$TUS.
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handler 0=9$k
* @param everyPage q&:%/?)x
* @param currentPage O"X7 DgbC
* @param totalRecords GUJ?6;
* @return page WFmW[< g
*/ 3:c6x kaw
publicstatic Page createPage(int everyPage, int cUw$F{|W
)RWY("SUy1
currentPage, int totalRecords){ ?oV|.LM:W
everyPage = getEveryPage(everyPage); &tiJ=;R1
currentPage = getCurrentPage(currentPage); &-My[t
int beginIndex = getBeginIndex(everyPage, [s]
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currentPage); !X[7m
int totalPage = getTotalPage(everyPage,
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X #$l7I9H
totalRecords); Qip@L WvT
boolean hasNextPage = hasNextPage(currentPage, #g2&x sU
NE &{_i!
totalPage); #7YJ87<E
boolean hasPrePage = hasPrePage(currentPage); gTLBR
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returnnew Page(hasPrePage, hasNextPage, m*lcIa
everyPage, totalPage, yI-EF)A@;
currentPage, oykb8~u}}
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beginIndex); wT,=C'
} va"bw!zXo*
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privatestaticint getEveryPage(int everyPage){ * vqUOh
return everyPage == 0 ? 10 : everyPage; l?xd3Z@7[
} ]1[:fQF7/L
.E7"Lfs-
privatestaticint getCurrentPage(int currentPage){ alsD TQ'
return currentPage == 0 ? 1 : currentPage; \IqCC h
} n7/&NiHxv/
nYBa+>3BDf
privatestaticint getBeginIndex(int everyPage, int ^nFP#J)_5
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;-x
currentPage){ ]$-<< N{}'
return(currentPage - 1) * everyPage; N>)Db
} : Hu{MN\
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privatestaticint getTotalPage(int everyPage, int ;R@D
sfy}J1xIL
totalRecords){ Bob-qCBV
int totalPage = 0; >4+KEK
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if(totalRecords % everyPage == 0)
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totalPage = totalRecords / everyPage; PY+4OZ$
else Qf'g2
\
totalPage = totalRecords / everyPage + 1 ; `z7,HJ.0c
fILvEf4b
return totalPage; ~Jj~W+h
} Tgbq4xR(
=NNxe"Kd;U
privatestaticboolean hasPrePage(int currentPage){ 3kwkU
return currentPage == 1 ? false : true; W|s";EAM
} q_9 tbZ;
W u$yB!
privatestaticboolean hasNextPage(int currentPage, DhsvN&yNM
)ac!@slb^7
int totalPage){ +NiCt S
return currentPage == totalPage || totalPage == /f AAQ7
@:>gRD
0 ? false : true; ~zWLqnS}
} hp2$[p6O
MGre_=Dm_
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} ;=6EBP%
,^DP
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A<( DYd1H
Ea-U+7JC
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。 dt"&
_8\B~;0
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 +!$`0v
}WBHuVcZG
做法如下: ~_g{P3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 @S>;t)\J
Ap4.c8f?Q-
的信息,和一个结果集List: $~%h4
java代码: 4x#tUzb;
{2i8]Sp1d/
33&\E- Q>
/*Created on 2005-6-13*/ _c5*9')-)
package com.adt.bo; 4:/^ .:
- leYR`P
import java.util.List; |f.,fVVV;
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import org.flyware.util.page.Page; {OOn7=
$ \o)-3
/** tvq((2
* @author Joa F!*GrQms
*/ ?zbW z=nq
publicclass Result { wkV'']= Xg
BL"7_phM,
private Page page;
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YBF$/W+=9|
private List content; <$otBC/%
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/** &
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* The default constructor Bvh{|tP4
*/ 1i'y0]f
public Result(){ 1uB$@a\
super(); #VVfHCy
} \<G"9w
|{_>H'
/** $J&c1
* The constructor using fields hhFO,
* 7T t!hf
* @param page ]0j_yX
* @param content !]RSG^%s{
*/ ~P;A
9A(k
public Result(Page page, List content){ j2.7b1s
this.page = page; S kB*w'k
this.content = content; yf4L0.
} TY'61xWi
IOY7w"|LW
/** /SQ/$`1{
* @return Returns the content. WIpV'F|t]`
*/ fGRV]6?V
publicList getContent(){ 4"\cA:9a
return content; .aVt d
[
} 3dolrW
Re
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/** U~;tk@
* @return Returns the page. +lhCF*@*N
*/ %H2ios[UO
public Page getPage(){ o
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return page; &g1\0t
} c"pOi&
9cU9'r# h
/** 3eXIo=
* @param content 4RYH^9;>K
* The content to set. 5Z5x\CcC3
*/ |r36iUHZS
public void setContent(List content){ Id>4fF:o
this.content = content; t8rFn
} D|Wlq~IpQ
Kfr1k
/** kxJ[Bi#
* @param page j0V/\Ep)T<
* The page to set. Pd(_
*/ tMp!MQ
publicvoid setPage(Page page){ 7')W+`o8eL
this.page = page; ,]W|"NUI
} G -+!h4p
} slUi)@b
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/F(n%8)Yq
K7K/P{@9[9
2. 编写业务逻辑接口,并实现它(UserManager, o[iN/
8&|
o
UserManagerImpl) Ke?,AWfG
java代码: fwV2b<[
79exZ7|
ahy6a,)K~
/*Created on 2005-7-15*/ T<?kH
package com.adt.service; FO:L+&hr?>
^\?Rh(pu
import net.sf.hibernate.HibernateException; s&-MJ05y
aekke//y
import org.flyware.util.page.Page; w}zmcO:x
?+^p$'5
import com.adt.bo.Result; a.}#nSYP
M*kE |q/K
/** 0doJF@H
* @author Joa IDFzyg_
*/ QuPz'Ut#
publicinterface UserManager { /lu|FWbEw
%Uz\P|6PO
public Result listUser(Page page)throws G8klWZAJ
f:<BUqa
HibernateException; f17E2^(I(}
}^ ,D~b-nB
} r9'[7b1l
M(LIF^'U:m
{7z]+ h
emK*g<]
.hR
<{P
java代码: #~"IlBk\
C49\'1\6
X.k8w\~
/*Created on 2005-7-15*/ }6/M5zF3
package com.adt.service.impl; ~uty<fP
/pPH D]
import java.util.List; PQ[?zNrSV
X )tH23
import net.sf.hibernate.HibernateException; -bzlp7q*
5~@-LXqL
import org.flyware.util.page.Page; aaT3-][
import org.flyware.util.page.PageUtil; j2UQQFh
e&d$kUJrq
import com.adt.bo.Result; \GxqE8
import com.adt.dao.UserDAO; KGg
S"d
import com.adt.exception.ObjectNotFoundException; ]0ErT9
import com.adt.service.UserManager; #?>)5C\Hqy
]Z8u0YtM)
/** ?{J1Uw<
* @author Joa pka^7OWyN
*/ Af]zv~uM
publicclass UserManagerImpl implements UserManager { 0P9\; !Y
8TT#b?d
private UserDAO userDAO; Cd
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;Jg$C~3tf
/** \2 N;VE
* @param userDAO The userDAO to set. v#%rjml[
*/ otR7E+*3
publicvoid setUserDAO(UserDAO userDAO){ |<,qnf| -
this.userDAO = userDAO; vu\W5M
} =CK% Zo
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/* (non-Javadoc) ^]R_t@
* @see com.adt.service.UserManager#listUser O0L]xr
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7 U6p
(org.flyware.util.page.Page) W6NhJ#M7
*/ f^B8!EY#:
public Result listUser(Page page)throws
*af\U3kx
S
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HibernateException, ObjectNotFoundException { bXF8V
int totalRecords = userDAO.getUserCount(); c-XO}\?
if(totalRecords == 0) =JzzrM|V*
throw new ObjectNotFoundException E4892B:`
?96r7C|
("userNotExist"); xOj#%;
page = PageUtil.createPage(page, totalRecords); v.Bwg7R3
List users = userDAO.getUserByPage(page); C?gqX0[ q
returnnew Result(page, users); HJ7A/XW
} 8$_{R!x
]?@ [Ny=0
} DPxx9lN_rx
;7:} iKU
7CH&n4v
KJec/qca
cLf90|YFp
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 a~0 ~Y y
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G>F
询,接下来编写UserDAO的代码: %u66H2
3. UserDAO 和 UserDAOImpl: uD=Kar
java代码: Eb[;nk?
t;w<n"
<PDCM8
/*Created on 2005-7-15*/ !?JZ^/u
package com.adt.dao; pS+w4gW
?;~E*kzO&
import java.util.List; qP#LJPaS
~Yk^(hl2
import org.flyware.util.page.Page; >=; -:
g:Qq%'
import net.sf.hibernate.HibernateException; )
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B1 }-
/** /'jX_
V_$|
* @author Joa gPk,nB
*/ mc?IM(t
publicinterface UserDAO extends BaseDAO { yl~;!
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publicList getUserByName(String name)throws hb3:,c(
g@>llve{
HibernateException; '=E;^'Rl
3oLF^^^g
publicint getUserCount()throws HibernateException; [E
a{);
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publicList getUserByPage(Page page)throws TS6xF?
,M3hE/rb/
HibernateException; 3(V0,L'1
qo3+=*"V
} -fA =&$V
>B0AJW/u
P".}Y[GD
vK)'3%
6}E>B{Y
java代码: yk?bz
R%RbC!P
ZcXAqep8'
/*Created on 2005-7-15*/ T4.wz
58
package com.adt.dao.impl; ;99oJD,
N E9,kWI
import java.util.List; wkZwtq
,gQl_Amvz
import org.flyware.util.page.Page; uxTgK'3
Hj{.{V
import net.sf.hibernate.HibernateException; 8*0QVFn$
import net.sf.hibernate.Query; Bp7p X
Li5&^RAo|J
import com.adt.dao.UserDAO; xS1n,gTA
USyc D`
/** vmAnBY
* @author Joa n5d8^c! 2
*/ `YqtI/-w
public class UserDAOImpl extends BaseDAOHibernateImpl yk4@@kHW
c46-8z$
implements UserDAO { Qa=Y?=Za
7zw0g~+
/* (non-Javadoc) /";tkad^
* @see com.adt.dao.UserDAO#getUserByName p}!i_P
e1W9"&4>G{
(java.lang.String) ]`$yY5 &W0
*/ h s',f
publicList getUserByName(String name)throws vz4(
k/
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HibernateException { L&kCI`Tb
String querySentence = "FROM user in class HN5661;8
;"Gy5
com.adt.po.User WHERE user.name=:name"; @)h>vg
Query query = getSession().createQuery cQt&%SVT]E
~NK $rHwi%
(querySentence); EF
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query.setParameter("name", name); !j'LZ7
return query.list(); 9Q,>I6`l
} }
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?]D&D:Z?I
/* (non-Javadoc) z9S
(<