Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 nL":0!DTRD
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 AK@`'$
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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 jSwtf
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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 Z#OhYm+y
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分页支持类: 96"yNqBf
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java代码: ;0w ^ud
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package com.javaeye.common.util; H[BD)
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import java.util.List; O6m.t%*
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publicclass PaginationSupport { `1E|PQbWc
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publicfinalstaticint PAGESIZE = 30; ;~Q
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privateint pageSize = PAGESIZE; |
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privateList items; w24{_ N
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privateint totalCount; aN^]bs?R
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privateint[] indexes = newint[0]; PGPISrf
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privateint startIndex = 0; }}^,7npU
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public PaginationSupport(List items, int j[J5y#
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totalCount){ C5O5S:|'
setPageSize(PAGESIZE); w5F4"nl#O}
setTotalCount(totalCount); ./'~];&
setItems(items); FAQr~G}
setStartIndex(0); sU) TXL'_!
} s<[A0=LH
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public PaginationSupport(List items, int EMVk:Vt]
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totalCount, int startIndex){ ?QCmSK=L
setPageSize(PAGESIZE); w)+wj[6
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setTotalCount(totalCount); A6Ghj{~
setItems(items); =N YgGEFq.
setStartIndex(startIndex); /y}"M
} "+=Pp
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public PaginationSupport(List items, int uije#cj#O
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totalCount, int pageSize, int startIndex){ /@ y;iJk;
setPageSize(pageSize); si_W:mLF{a
setTotalCount(totalCount); c |>=S)|
setItems(items); 21r==
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setStartIndex(startIndex); T vrk^!
} (GCG/8s
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publicList getItems(){ ?Bo?JMV
return items; OFc\fW#
} ojHhT\M`
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publicvoid setItems(List items){ t#C,VwMe[
this.items = items; !Eq#[Gs
} <d5@CA+M
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publicint getPageSize(){ >(X#<`
return pageSize; H2_/,n
} 0,HqE='w
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publicvoid setPageSize(int pageSize){ 4-mVB wq
this.pageSize = pageSize; 3Jk[/.h
} H&M1>JtE
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publicint getTotalCount(){ G6ayMw]OF
return totalCount; m#tpbFAsc
} ,V,f2W 4
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publicvoid setTotalCount(int totalCount){ 93j{.0]X
if(totalCount > 0){ M\Se_
this.totalCount = totalCount; eP "`,<
int count = totalCount / XAe\s`
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pageSize; "!O1j
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if(totalCount % pageSize > 0) |^R*4;Phe
count++; ((XE\V\}Z
indexes = newint[count]; m`z7fi7u
for(int i = 0; i < count; i++){ /
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indexes = pageSize * -."kq.m*
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} ~.J,A\F
}else{ tJNIr5o
this.totalCount = 0; zh\$t]d<I
} bNGCOj
} w5`#q&?
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publicint[] getIndexes(){ sYJL-2JX
return indexes; C5|db{=\.*
} <47k@Ym
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publicvoid setIndexes(int[] indexes){ &iNwvA%9D
this.indexes = indexes; l
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} OsQkA2=
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publicint getStartIndex(){ Us,)]W.S
return startIndex; =!BobC- [b
} FZF @
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publicvoid setStartIndex(int startIndex){ ciudRK63M
if(totalCount <= 0) ^"9*
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this.startIndex = 0; Rf)ke("
elseif(startIndex >= totalCount) ?7
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this.startIndex = indexes !^e =P%S
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[indexes.length - 1]; _T5)n=|
elseif(startIndex < 0)
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this.startIndex = 0; SR ZL\m}
else{ U3E&n1AA
this.startIndex = indexes pj0fM{E
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[startIndex / pageSize]; 5{d\uE%'p
} %d1draL
} |t))u`~
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publicint getNextIndex(){ |S&5es-yW
int nextIndex = getStartIndex() + y500Xs[c
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pageSize; :]PM_V|
if(nextIndex >= totalCount) P`S@n/}
return getStartIndex(); +f>c xA
else glE^t6)
return nextIndex; -Fxmsi
} =bLY
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publicint getPreviousIndex(){ N>|XS
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int previousIndex = getStartIndex() - (u hd "
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pageSize; ~=En+J}*
if(previousIndex < 0) bl;zR
return0; Ow:1?Z{4
else `]=oo%(h
return previousIndex; @*>Sw>oet
} C$d>_r
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抽象业务类 krB'9r<wa`
java代码: ~6aCfbu%V
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/** + H_WlYg-
* Created on 2005-7-12 %0,-.(h
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package com.javaeye.common.business; jjzA .8?(7
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import java.io.Serializable; )J D(`
import java.util.List; wW 2d\Zd&
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import org.hibernate.Criteria; egk7O4zwP
import org.hibernate.HibernateException; P[ r];e
import org.hibernate.Session; 47r&8C+&\
import org.hibernate.criterion.DetachedCriteria; f )Z%pgB
import org.hibernate.criterion.Projections; 17|np2~
import pI.+"Hz
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org.springframework.orm.hibernate3.HibernateCallback; l"(6]Z 4
import e`K)_>^n#
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org.springframework.orm.hibernate3.support.HibernateDaoS S'LZk9E
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upport; EW<kI+0D
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import com.javaeye.common.util.PaginationSupport; MZ>6o5K|
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public abstract class AbstractManager extends S4CbyXW
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HibernateDaoSupport { (ljF{)Ml+=
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privateboolean cacheQueries = false; _>m-AI4^
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privateString queryCacheRegion; 5O/i3m26
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publicvoid setCacheQueries(boolean %+)o'nf"U
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cacheQueries){ )B#
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this.cacheQueries = cacheQueries; h#r^teui)
} ^].jH+7i*
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publicvoid setQueryCacheRegion(String a:TvWzX,
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queryCacheRegion){ 6K`c/)
this.queryCacheRegion = h}`!(K^;3
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queryCacheRegion; 'XrRhF
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} H(
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publicvoid save(finalObject entity){ Y-mK+12
getHibernateTemplate().save(entity); {c?JuV4q?
} lbdTQ6R
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publicvoid persist(finalObject entity){ O,2~"~kF
getHibernateTemplate().save(entity); i':i_kU
} gi/@j
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publicvoid update(finalObject entity){ F>je4S;
getHibernateTemplate().update(entity); a ]Eg!Q
} A>`945|
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publicvoid delete(finalObject entity){ X?:o;wB
getHibernateTemplate().delete(entity); IP`6bMd
} 6qWdd&1
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publicObject load(finalClass entity, 2&'|Eqk
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finalSerializable id){ B(?Yw>Xd[
return getHibernateTemplate().load =]`lN-rYw
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(entity, id); j$UV/tp5T
} 2aw&YZ&Xo
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publicObject get(finalClass entity, fKC3-zm
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finalSerializable id){ /MMd`VrC2
return getHibernateTemplate().get Migd(uw'
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(entity, id); kE8>dmH23
} \!vN
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publicList findAll(finalClass entity){ 8P7"&VYc8
return getHibernateTemplate().find("from ml0.$z
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" + entity.getName()); ?\KM5^eX
} 99$
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publicList findByNamedQuery(finalString 7]xm2CHx5
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namedQuery){ t^]$!H
return getHibernateTemplate fkSO( C)
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().findByNamedQuery(namedQuery); ^D^4
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} J:uW`R
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publicList findByNamedQuery(finalString query, ^;,M}|<h
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finalObject parameter){ *<N3_tx"
return getHibernateTemplate >3 yk#U|7}
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().findByNamedQuery(query, parameter); 09A
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} F' U 50usV
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publicList findByNamedQuery(finalString query, b2 _Yu^
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finalObject[] parameters){ b|Q)[ y]
return getHibernateTemplate QB.J,o*XD4
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().findByNamedQuery(query, parameters); MMB@.W
} mk7&<M
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publicList find(finalString query){ 1Je9,dd6
return getHibernateTemplate().find L
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(query); P%)gO
} 5@*'2rO&!
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publicList find(finalString query, finalObject (~zd6C1.
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parameter){ m9U"[Huv1E
return getHibernateTemplate().find G?f\>QSZ
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(query, parameter); Z_\C*^
} ?JL7=o
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public PaginationSupport findPageByCriteria ^pn(=4
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(final DetachedCriteria detachedCriteria){ WI]o cF
return findPageByCriteria A:(*y
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); + OV')oE
} R52I=
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public PaginationSupport findPageByCriteria 3@5=+z~CW
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(final DetachedCriteria detachedCriteria, finalint G-9iowS/A
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startIndex){ SIBoCs5
return findPageByCriteria )54%HM_$k
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(detachedCriteria, PaginationSupport.PAGESIZE, -{^}"N
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startIndex); >]o}}KF?
} .0R v(Y
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public PaginationSupport findPageByCriteria {3N'D2N
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(final DetachedCriteria detachedCriteria, finalint eZ"1gYqy
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pageSize, E}%hz*Q)(
finalint startIndex){ 5[j`6l
return(PaginationSupport) T~h5B(J;
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getHibernateTemplate().execute(new HibernateCallback(){ <~
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publicObject doInHibernate 3\T2?w9u(
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(Session session)throws HibernateException { g$.
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Criteria criteria = @( n^T
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detachedCriteria.getExecutableCriteria(session); =]3tUD
int totalCount = bc
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((Integer) criteria.setProjection(Projections.rowCount FI"`DMb}
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()).uniqueResult()).intValue(); E( us'9c
criteria.setProjection vkLC-Mzm<
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(null); czlFr|O;
List items = ,lCgQ0}<
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criteria.setFirstResult(startIndex).setMaxResults <0S=,!
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(pageSize).list(); T{wuj[Q#:
PaginationSupport ps = u&wiGwF[
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new PaginationSupport(items, totalCount, pageSize, L@JOGCYy
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startIndex); #07g d#j4
return ps; :!zl^J;
} &@ JvnO:
}, true); (k np#
} +l=r#JF
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public List findAllByCriteria(final Z,iHy3`
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DetachedCriteria detachedCriteria){ A)ipFB
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return(List) getHibernateTemplate ioPUUUb)
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().execute(new HibernateCallback(){ |p$spQ
publicObject doInHibernate %'0TXr$
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(Session session)throws HibernateException { ah~YeJp
Criteria criteria = ,^icPQSwc
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detachedCriteria.getExecutableCriteria(session); @3kKJ
return criteria.list(); V`@>MOw^d
} O{ /q-~_
}, true); JI vo_7{
} H4]Ul
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public int getCountByCriteria(final JmEj{K<3I
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DetachedCriteria detachedCriteria){ u+{a8=
Integer count = (Integer) NY?;erX
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getHibernateTemplate().execute(new HibernateCallback(){ %c[ V
publicObject doInHibernate #pcP!
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(Session session)throws HibernateException { S;]*) i,v
Criteria criteria = Pb*5eXk
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detachedCriteria.getExecutableCriteria(session); a'\o7_
return SM@QUAXO
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criteria.setProjection(Projections.rowCount q{+_
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()).uniqueResult(); {/pm<k=
} ;NRF=d>
}, true); *{+G=d
return count.intValue(); .CFa9"<
} Ao/ jt<
} |g*XK6
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用户在web层构造查询条件detachedCriteria,和可选的 IT$25ZF
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2<}NB?f`N
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PaginationSupport的实例ps。 DfKr[cqLM
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ps.getItems()得到已分页好的结果集 yeHDa+}
ps.getIndexes()得到分页索引的数组 VWO9=A*Y|
ps.getTotalCount()得到总结果数 o: ;"w"G
ps.getStartIndex()当前分页索引 0
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ps.getNextIndex()下一页索引 Qqlup
ps.getPreviousIndex()上一页索引 ":_vK}5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 QD%L0;j
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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 rl0< Ls
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一下代码重构了。 T*KMksjxm`
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我把原本我的做法也提供出来供大家讨论吧: JY6
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首先,为了实现分页查询,我封装了一个Page类: {GJ@psG*
java代码: J(6oL
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/*Created on 2005-4-14*/ [}&Sxgv
package org.flyware.util.page; AFAAuFE"
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/** $LU"?aAW
* @author Joa v,ju!I0.
* RSo&