Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .xBu-?6s6
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }MUn/ [x
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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 %Qk/_ R1
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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 G9JAcO1
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分页支持类: -(K9s!C!.
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java代码: D-N8<:cA
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package com.javaeye.common.util; n@ G[
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import java.util.List; "O(9 m.CZ
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publicclass PaginationSupport { *}8t{ F@k
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publicfinalstaticint PAGESIZE = 30; ES40?o*]x
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privateint pageSize = PAGESIZE; yV^s,P1
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privateList items; FN[{s
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privateint totalCount; h>Hb`G<
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privateint[] indexes = newint[0]; ~jsLqY*(+
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privateint startIndex = 0; +o9":dl
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public PaginationSupport(List items, int r7',3V
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totalCount){ \_B[{e7z
setPageSize(PAGESIZE); ^+g$iM[`f
setTotalCount(totalCount); {P*m;a`}
setItems(items); O|w J)
setStartIndex(0); DY^;EZ!hb
} l<);s
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public PaginationSupport(List items, int ){UcS/GI=
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totalCount, int startIndex){ ttu&@
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setPageSize(PAGESIZE); 0'IBN}
setTotalCount(totalCount); 73){K?R
setItems(items); x7$}8LZ"B
setStartIndex(startIndex); I(XOE$3
} h*v8#\b$J_
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public PaginationSupport(List items, int ]9@F~)
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totalCount, int pageSize, int startIndex){ =W'Ae,&
setPageSize(pageSize); r-<F5<H+K@
setTotalCount(totalCount); IC7M$
setItems(items); [Vma^B$7Vj
setStartIndex(startIndex); ,{mCf^
} ?Ec7" hK
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publicList getItems(){ zE_i*c"`
return items; D
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} ,I,\ml
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publicvoid setItems(List items){ X*\J_
this.items = items; #{\%rWnCm
} JeE;V![
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publicint getPageSize(){ ej"+:."\e
return pageSize; 0vw4?>Jf@
} VTH>
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publicvoid setPageSize(int pageSize){ ^-
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this.pageSize = pageSize; -(=eM3o-9m
} 3p'I5,}
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publicint getTotalCount(){ GmP@;[H"
return totalCount; 8Q'0h
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} {yExQbN
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publicvoid setTotalCount(int totalCount){ 2=^m9%
if(totalCount > 0){ n<u
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this.totalCount = totalCount; X)% A6M
int count = totalCount / ZEx}$<)_
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pageSize; 0ik7v<:
if(totalCount % pageSize > 0) 9_5ow
count++; |/)${*a4n
indexes = newint[count]; :n-]>Q>5=k
for(int i = 0; i < count; i++){ s']Bx=
indexes = pageSize * $A-J,_:T<
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} sc,vj'r
}else{ )'+8}T]xQ
this.totalCount = 0; WA&!;Zq
} #NryLE!/
} bXNk%W[n
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publicint[] getIndexes(){ (:>,u*x%
return indexes; Bn &Ws
} q1KZ5G)6GJ
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publicvoid setIndexes(int[] indexes){ Sxh]R+Xb
this.indexes = indexes; XY3v_5~/1F
} ] &Rx@&e*
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publicint getStartIndex(){ #*UN >X
return startIndex; Rw0qcM\>|
} |3KLk ?2
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publicvoid setStartIndex(int startIndex){ Y<%@s}zc
if(totalCount <= 0) '?p<lu^^B
this.startIndex = 0; wLnf@&jQ%
elseif(startIndex >= totalCount) 9eQxit7
this.startIndex = indexes dx@-/^.
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[indexes.length - 1]; 2HsLc*9{4
elseif(startIndex < 0) ,tu.2VQc@
this.startIndex = 0; |$
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else{ #ZrHsfP
this.startIndex = indexes ) iN/ua
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[startIndex / pageSize]; DBr
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} lSVp%0jR
} fO[+LR
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publicint getNextIndex(){ I$Op:P6.E
int nextIndex = getStartIndex() + Zm_UR*"
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pageSize; ;"~
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if(nextIndex >= totalCount) hRD=Y<>A
return getStartIndex(); `ux{;4q
else 0?:} P
return nextIndex; {ix?Brq/
} EWkLXU6t
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publicint getPreviousIndex(){ GkTiDm?
int previousIndex = getStartIndex() - CU@Rob} s
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pageSize; 9\mLW"
if(previousIndex < 0) &&8IU;J
return0; `n@*{J8
else 6"J?
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return previousIndex; q!u~jI9j
} n%o5kVx0
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} wc}5m
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抽象业务类 #Oc]
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java代码: yDegcAn?
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/** Rnr(g;2
* Created on 2005-7-12 Q/(K$6]j
*/ v50bdj9}k
package com.javaeye.common.business; "8x8UgG
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import java.io.Serializable; 1AM!8VR2
import java.util.List; $!-c-0ub
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import org.hibernate.Criteria; SwTL|+u
import org.hibernate.HibernateException; }J:U=HJ
import org.hibernate.Session; KyYM fC
import org.hibernate.criterion.DetachedCriteria; AQ,'
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import org.hibernate.criterion.Projections; '$ =>
import Mh:L$f0A%O
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org.springframework.orm.hibernate3.HibernateCallback; e478U$
import G\Cp7:j}
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org.springframework.orm.hibernate3.support.HibernateDaoS wnEyl[ac
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upport; YQ9'0F[l
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import com.javaeye.common.util.PaginationSupport; aW)-?(6>
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public abstract class AbstractManager extends \IV1j)I"u
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HibernateDaoSupport { }Qn&^[[miL
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privateboolean cacheQueries = false; ODNM+#}`
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privateString queryCacheRegion; bpJ(XN}E
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publicvoid setCacheQueries(boolean
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cacheQueries){ Ai=se2
this.cacheQueries = cacheQueries; A+ZK4]xb
} la0BiLzb]
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publicvoid setQueryCacheRegion(String =.f-w0V
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queryCacheRegion){ K6v6ynp/
this.queryCacheRegion = &C,'x4c"
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queryCacheRegion; }Z@ovsG
} nm5cpnNl
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publicvoid save(finalObject entity){ /YP{,#p
getHibernateTemplate().save(entity); sJ;g$TB
} vj'wm}/
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publicvoid persist(finalObject entity){ Bu<M\w?7Y
getHibernateTemplate().save(entity); ;4R$g5-4X
} wSzv|\
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publicvoid update(finalObject entity){ +7D|4
getHibernateTemplate().update(entity); 0=@?ob7
} OE_XCZ!5P
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publicvoid delete(finalObject entity){ /32Fy`KV
getHibernateTemplate().delete(entity); X@+{5%
} n7B7 m,@1
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publicObject load(finalClass entity, "bFTk/
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finalSerializable id){ we~[ ]
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return getHibernateTemplate().load :q$.,EZ4#n
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(entity, id); >Wm`v.-
} q8X feoUV
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publicObject get(finalClass entity, 2iY3Lsna
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finalSerializable id){ #|Y5,a,{
return getHibernateTemplate().get ][gq#Vx@
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(entity, id); 5,3'=mA6
} hm84Aq= f
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publicList findAll(finalClass entity){ 1->dMm}G[
return getHibernateTemplate().find("from jqWu
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" + entity.getName()); <C1H36p
} C]O(T2l{l
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publicList findByNamedQuery(finalString x[wq]q#*
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namedQuery){ @K\~O__
return getHibernateTemplate q}`${3qQ3
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().findByNamedQuery(namedQuery); _GXk0Ia3`
} j~2{lCT
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publicList findByNamedQuery(finalString query, [.O?Z=5a[V
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finalObject parameter){ .f*4T4eR-
return getHibernateTemplate _Zp}?b5Q
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().findByNamedQuery(query, parameter); |'.*K]Yp
} 1Ce@*XBU
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publicList findByNamedQuery(finalString query, r54&XE]O
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finalObject[] parameters){ 9A/\h3HrJ
return getHibernateTemplate Hbj,[$Jb
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().findByNamedQuery(query, parameters); }6p@lla,%]
} PXK7b2fE.
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publicList find(finalString query){ Lz`E;k^
return getHibernateTemplate().find \s/s7y6b+
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(query); ^ssK
} lW+\j3?Z$
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publicList find(finalString query, finalObject O!mvJD
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parameter){ `_BNy=`s*
return getHibernateTemplate().find fL_4uC i\
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(query, parameter); zcel|oz)
} "W=AB&
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public PaginationSupport findPageByCriteria KK1gNC4R
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(final DetachedCriteria detachedCriteria){ ujDd1Bxf?
return findPageByCriteria C\S3Gs
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); RTvqCp
} HTVuStM8
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public PaginationSupport findPageByCriteria S/}2; \Xm
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(final DetachedCriteria detachedCriteria, finalint E=jNi
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startIndex){ >z/#_z@LV
return findPageByCriteria r;B8i!gD
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(detachedCriteria, PaginationSupport.PAGESIZE, TlXI|3Ip
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startIndex); D2<fw#
} ^"VJd[Hn
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public PaginationSupport findPageByCriteria "8c@sHk(w
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(final DetachedCriteria detachedCriteria, finalint #D<C )Q
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pageSize, O;z,qo X
finalint startIndex){ ~rlB'8j(
return(PaginationSupport) ~?D4[D|sB
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getHibernateTemplate().execute(new HibernateCallback(){ _76PIR{an
publicObject doInHibernate yL%K4$z
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(Session session)throws HibernateException { NhfJ30~
Criteria criteria = rx $mk
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detachedCriteria.getExecutableCriteria(session); zAK+8{,
int totalCount = {!.(7wV\
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((Integer) criteria.setProjection(Projections.rowCount RS"H8P4W
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()).uniqueResult()).intValue(); u}>#Eb
criteria.setProjection |S_T^'<W
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(null); B268e
List items = FYOD
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criteria.setFirstResult(startIndex).setMaxResults us;YV<)d
y)F;zW<+
(pageSize).list(); _wC3kAO
PaginationSupport ps = ?Eg(Gu.J
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new PaginationSupport(items, totalCount, pageSize, FqkDKTS\&
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startIndex); 7Ilm{@b=
return ps; N/]o4o
} ;KOLNi-B&
}, true); RSr
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} !$DIc
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public List findAllByCriteria(final )!Jc3%(B
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DetachedCriteria detachedCriteria){ pwO>h>ik
return(List) getHibernateTemplate CEXyrs<
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().execute(new HibernateCallback(){ &Flglj~7l
publicObject doInHibernate dI*pDDq#
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(Session session)throws HibernateException { -mC0+}h
Criteria criteria = w3#Wh|LQ-
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detachedCriteria.getExecutableCriteria(session); s4G|_==
return criteria.list(); A:>01ZJ5S+
} cmBB[pk\
}, true); ^:K3vC[h;c
} un shH <
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public int getCountByCriteria(final 0T@ Zb={
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DetachedCriteria detachedCriteria){ &yGaCq;0
Integer count = (Integer) $h^wG)s2P
_ 6O\W%it
getHibernateTemplate().execute(new HibernateCallback(){ bnm
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publicObject doInHibernate L>MLi3{
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(Session session)throws HibernateException { yN~dU0.G6!
Criteria criteria = ^w(p8G_-w
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detachedCriteria.getExecutableCriteria(session); 0F@"b{&0
return EM]s/LD@%
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criteria.setProjection(Projections.rowCount +IrLDsd
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()).uniqueResult(); GRGzP&}@
} ^sa#8^,K
}, true); jL(qf~c_
return count.intValue(); :Nu^
} M54j@_81pX
} H:!7:
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用户在web层构造查询条件detachedCriteria,和可选的 AP[|Ta
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 .zS?9MP
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PaginationSupport的实例ps。 pF&(7u
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ps.getItems()得到已分页好的结果集 =jSb'Vu|
ps.getIndexes()得到分页索引的数组 A~Y^VEn
ps.getTotalCount()得到总结果数 b}0,\B%
ps.getStartIndex()当前分页索引 OTMJ6)n7
ps.getNextIndex()下一页索引 Vm%1> '&
ps.getPreviousIndex()上一页索引 $P>`m$(8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }-ftyl7
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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 O?U'!o=
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一下代码重构了。 "5;;)\o~
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我把原本我的做法也提供出来供大家讨论吧: ~7Ts_:E-
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首先,为了实现分页查询,我封装了一个Page类: jZh';M8"
java代码: 7s"<
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/*Created on 2005-4-14*/ D!.[q -<
package org.flyware.util.page; ()K " c#
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/** i-bJS6
* @author Joa wB.Nn/p
* K)qF+Vb^j
*/ At flf2 K
publicclass Page { S>.SSXlM
Q@
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/** imply if the page has previous page */ (Q%'N3gk
privateboolean hasPrePage; ~\=1'D^6CK
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/** imply if the page has next page */ L !=4N!j
privateboolean hasNextPage; _7IKzUn9g[
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/** the number of every page */ M7+nW ; e%
privateint everyPage; Ul2R'"FB
d*A*y ^OD
/** the total page number */ la( <8
privateint totalPage; T32+3wb"I
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/** the number of current page */ A$#p%yb
privateint currentPage; 6fd+Q
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/** the begin index of the records by the current GytXFL3`:
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query */ YhOlxON
privateint beginIndex; WA]c=4S
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/** The default constructor */ 2R=DB`3
public Page(){ bhkUKxd
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J
} }:u~K;O87
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/** construct the page by everyPage (S xR`QP?,
* @param everyPage Mu{;vf|j
* */ Nc+,&R13m
public Page(int everyPage){ o4*+T8[|5
this.everyPage = everyPage; ;3\3q1oX
} w;k):;$
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/** The whole constructor */ Jd5:{{Lb
public Page(boolean hasPrePage, boolean hasNextPage, tjGd )
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int everyPage, int totalPage, PZ{Dv'C
int currentPage, int beginIndex){ KN7^:cC
this.hasPrePage = hasPrePage; K$ M^gh0
this.hasNextPage = hasNextPage; qw@puw@D
this.everyPage = everyPage; U+)xu>I
this.totalPage = totalPage; 3dht!7/
this.currentPage = currentPage; _<a7CCg
this.beginIndex = beginIndex; e=4+$d
} oI}kH=<,
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/** UilMv~0
* @return Vs%|pIV
* Returns the beginIndex. 3 n'V\Hvz
*/ L]d-hs
publicint getBeginIndex(){ D8>enum
return beginIndex; EI_
} ,z;ky5Ct
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/** 1Ab>4UhD
* @param beginIndex C8vOE`U,J
* The beginIndex to set. ^
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*/ YnxRg
publicvoid setBeginIndex(int beginIndex){ n|b5? 3
this.beginIndex = beginIndex; ,y+$cM(
} :JfE QIN
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/** F)+{AQL
* @return d}JP!xf%
* Returns the currentPage. 6KVnnK
*/ &^}6
9
publicint getCurrentPage(){ |1ST=O7.LH
return currentPage; +)j1.X
} h$.:Uj8/
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/** jM$`(Y
* @param currentPage 3GuH857ov
* The currentPage to set. &}?$i7x5
*/ ;5tazBy&:C
publicvoid setCurrentPage(int currentPage){ zo[[>MA
this.currentPage = currentPage; ^|/](
} W?eu!wL#p
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/** 0pJ
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* @return ZTU&,1Y ;
* Returns the everyPage. rAs,X
*/ 2Fz|fW_
publicint getEveryPage(){ VxY+h`4#
return everyPage; (y?ITz9
} vfl5Mx4
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/** Ya;9]k8,
* @param everyPage 6I!7c^]t
* The everyPage to set. :=8t"rO=W
*/ c%[#~;E
publicvoid setEveryPage(int everyPage){ KN?6;G{
this.everyPage = everyPage; ;zYqsS
} a)S+8uU
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/** DK=cVpN%s
* @return B Ce|is0
* Returns the hasNextPage. &Ch#-CUE/
*/ T"&)&"W*U
publicboolean getHasNextPage(){ FL8g5I
return hasNextPage; - !>}_AH
} OvUI@,Ef
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/** "Ae@lINn[y
* @param hasNextPage
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* The hasNextPage to set. >[Ye
*/ @#P,d5^G
publicvoid setHasNextPage(boolean hasNextPage){ 549jWG
this.hasNextPage = hasNextPage; #fJ] o_
} rQEyD
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/** 9elga"4:'
* @return OKi\zS
* Returns the hasPrePage. vTaJqEE
*/ 'Fs)Rx}\0
publicboolean getHasPrePage(){ KAsS[
return hasPrePage; *1 G>YH
} p_UlK8rb
@&]#uRl|[
/** <L{(Mj%Z
* @param hasPrePage 8ZCo c5
* The hasPrePage to set. wtT}V=_
*/ &z]K\-xp
publicvoid setHasPrePage(boolean hasPrePage){ lip[n;Ir>
this.hasPrePage = hasPrePage; 8[|UgI,>z
} 4n
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kKPi:G52F
/** W`"uu.~f
* @return Returns the totalPage. +uBLk0/)>
* 2_ :n
*/ P\]B<
publicint getTotalPage(){ 70lfb`
return totalPage; n.sbr
} fM #7 y [
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/** @"Z7nJX
* @param totalPage :> & fV
* The totalPage to set. y!5$/`AF
*/ n!')wIk
publicvoid setTotalPage(int totalPage){ 5C"QE8R o
this.totalPage = totalPage; <5G{"U+ \
} .`7cBsXH
=l.+,|ZH!
} [HN|\afz
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 >Bs#Xb_B]
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个PageUtil,负责对Page对象进行构造: DAwqo.m
java代码: ?x^z]N|P
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/*Created on 2005-4-14*/ 6G}+gqbX
package org.flyware.util.page; DfV~!bY
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import org.apache.commons.logging.Log; p~ .8\bI=
import org.apache.commons.logging.LogFactory; hoT/KWD,
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/** +525{Tj
* @author Joa @Kf_z5tm:
* AW#<i_Ybf
*/ Z4){
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publicclass PageUtil {
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privatestaticfinal Log logger = LogFactory.getLog H'MJ{r0,
MG /,==
(PageUtil.class); tTN?r 8
'TTUN=y
/** ~2d:Q6
* Use the origin page to create a new page k|BHnj
* @param page vA)O{W\o
* @param totalRecords k8,?hX:
* @return s/:Fwr4q#a
*/ p'sc0@}_O
publicstatic Page createPage(Page page, int 0aoHKeP
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totalRecords){ 9S[XTU
return createPage(page.getEveryPage(), >a1{397Y}
;.wX@
page.getCurrentPage(), totalRecords); QRLJ_W^&u
} )RYG%
bS
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/** ubu?S%`
* the basic page utils not including exception &TG5rUUg
7O`o ovW$
handler ](eN@Xi&@
* @param everyPage ^`SA'F,
* @param currentPage )2DQ>cm
* @param totalRecords XhdSFxW}
* @return page xyH/e*a
*/ 8F)G7
H,
publicstatic Page createPage(int everyPage, int 577:u<Yt
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currentPage, int totalRecords){ ^v9|%^ug
everyPage = getEveryPage(everyPage); YpUp@/"
currentPage = getCurrentPage(currentPage); Omi^>c4G
int beginIndex = getBeginIndex(everyPage, ?EU\}N J
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currentPage); r}u%#G+K,
int totalPage = getTotalPage(everyPage, I
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totalRecords); {FN;'Uc
boolean hasNextPage = hasNextPage(currentPage, iqhOi|!
G5D2oQa=8
totalPage); CK_(b"
boolean hasPrePage = hasPrePage(currentPage); *n(> ^
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returnnew Page(hasPrePage, hasNextPage, y[O-pD`
everyPage, totalPage, +pH@oFNK
currentPage, \Hqc9&0
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beginIndex);
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} )'Wb&A'
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privatestaticint getEveryPage(int everyPage){ @c'|Iqy`
return everyPage == 0 ? 10 : everyPage; ~#}Dx
:HH
} <DH*~tLp2
i`)!X:j
privatestaticint getCurrentPage(int currentPage){ tvX>{-M
return currentPage == 0 ? 1 : currentPage; Fv?=Z-wk
} j%<}jw[2
6AN)vs}
privatestaticint getBeginIndex(int everyPage, int Rq~t4sA:
+:6Ii9GN
currentPage){ iA!7E;o
return(currentPage - 1) * everyPage; t ]c{c#N/
} Io2mWvu?5
E?PGu!&u
privatestaticint getTotalPage(int everyPage, int 4c~>ci,N?(
Bn]K+h\E
totalRecords){ 7:h!Wj-a]
int totalPage = 0; ,J mbqOV?!
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if(totalRecords % everyPage == 0) '?o9VrO
totalPage = totalRecords / everyPage; R*1kR|*_)
else *jzLFuWIG
totalPage = totalRecords / everyPage + 1 ; "`A :(<x
vMSW$Bx ;
return totalPage; K:yr-#(P/
} C9Bh@v%90^
<Y'>F!?#
privatestaticboolean hasPrePage(int currentPage){ (I{
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return currentPage == 1 ? false : true; tJ&5tNl
} A%Z)wz{
7s'- +~
privatestaticboolean hasNextPage(int currentPage, $e\N+~KNCy
%@ mGK8
int totalPage){ i(2y:U3[@
return currentPage == totalPage || totalPage == <XQ.A3SG!
HTz+K6&
0 ? false : true; c\cZ]RZ
} MM{_Ur7Q
$2z
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X`zC^z}
} eukA[nO7G
myQ&%M
gx
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U[_8WJ7+
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 j?(!^ _!m
0?bA$y
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 9w;?-
5b#QYu
做法如下: us)*2`?6t
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 H5wb_yBQ+
J/D|4fC
的信息,和一个结果集List: ),@f6](
java代码: wpPn}[a
83]PA<R
sLcY,AH
/*Created on 2005-6-13*/ Y'"N"$n'_
package com.adt.bo; +1{fzb>9_
;Fl<v@9
import java.util.List; cep$_Ja
}4c/YP"a'E
import org.flyware.util.page.Page; 2BB<mv
K4
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/** `U`#I,Ln[
* @author Joa c5i%(!>
*/ e (\I_
publicclass Result { 'Am- vhpm
rjojG59U>
private Page page; 'u[%}S38
;\b@)E}
private List content; (wt+`_6
k{Lv37H
/** Wr|G:(kw\!
* The default constructor HD # r0)
*/ ZykrQ\q9
public Result(){ ~I_owCVZ
super(); 8<PKKDgbfd
} E[Bo4?s&^
k&s; {|!
/** XQ;I,\m
* The constructor using fields ['Z{@9
* 66ohmP@04Z
* @param page ^7XAw:
?
* @param content }Zl"9A#K
*/ ;[5r7
jHU
public Result(Page page, List content){ k
'zat3#f
this.page = page; -l*A
this.content = content; \aSz2lxEHn
} ZCiY,;c
oK Kz 4
/** )+~E8yK
* @return Returns the content. 9Vh_[^bR
*/ 3o8\/-*<
publicList getContent(){ Y)p4]>lT+8
return content; Gbb\h
} INNAYQ
+l\<?
/** yFeeG3n3
* @return Returns the page. $p6N|p
*/ Q-('5a19J
public Page getPage(){ :1<~}*B@{
return page; M9"Sgb`g
} h`?k.{})M
!$kR ;Q"/
/** jXcNAl
* @param content B?(4f2yE
* The content to set. oX|?:MS:
*/ QrS$P09=\
public void setContent(List content){ __)qw#
this.content = content; nm):SEkC
} P/aDd@j
t .=Oj
/** 5+L8\V9;
* @param page :('I)C
* The page to set.
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*/ ba&o;BLUy
publicvoid setPage(Page page){ BlaJl[P iv
this.page = page; B7 c[4
} _Y#Bm/*
} {%7<"
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/2w@K_Px6
qX@9N=g`#O
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2. 编写业务逻辑接口,并实现它(UserManager, #O|lfl>}
Bcaw~WD
UserManagerImpl) bF6gBM@*
java代码: S:Xs'0K_
(Jpm
K O
aL)Hv k:
/*Created on 2005-7-15*/
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package com.adt.service; )F
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0M\NS$u(Y
import net.sf.hibernate.HibernateException; P`2&*2,
>EBC 2WJ
import org.flyware.util.page.Page; K -E`y
DB8s
import com.adt.bo.Result; ADBpX>
41'EA\V
/** ,9vJtP+T+!
* @author Joa )*HjRTF6G
*/ 3ZN>9`
publicinterface UserManager { [d:@1yc
4WG=m}X
public Result listUser(Page page)throws #Q+R%p[D
=c]a
{|W?
HibernateException; H5p5S\g-)
\\s?B K
} =h[yAf
@YB85p"]J.
R-C5*$
`,m7xJZ?y
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java代码: A^vvST%7
EE9vk*[@C
3{q[q#"
/*Created on 2005-7-15*/ `oPLl0
package com.adt.service.impl; v>:=w|.HC
[a+4gy
import java.util.List; ^Fvr
f`A'
T^NJ4L4#
import net.sf.hibernate.HibernateException; o'^phlX
Z"N(=B
import org.flyware.util.page.Page; x_|>n<Z
import org.flyware.util.page.PageUtil; qOgtGN}k
bQV("~#
import com.adt.bo.Result;
2$)mC9
import com.adt.dao.UserDAO; 1gk0l'.z
import com.adt.exception.ObjectNotFoundException; X#7}c5^Y
import com.adt.service.UserManager; PvuAg(?
*k[kV
/** _Z.;u0Zp8
* @author Joa c.-cpFk^L&
*/ .t:DvB
publicclass UserManagerImpl implements UserManager { bN!u}DnN
p_gA/. v=
private UserDAO userDAO; d/4ubf+$k
)^(P@D.L
/** 6d};|#}
* @param userDAO The userDAO to set. k%!VP=c4s
*/ v*Xk WH5
publicvoid setUserDAO(UserDAO userDAO){ uZ<%kV1B
this.userDAO = userDAO;
,| <jjq)
} -[<vYxX:h:
QSv^l-<
/* (non-Javadoc) &|NZ8:*+#
* @see com.adt.service.UserManager#listUser bkkSIl+Q
*bU% @O
(org.flyware.util.page.Page) ik1XGFy?
*/ ?4MSgu
public Result listUser(Page page)throws HoV{U zm
ysl8LK
HibernateException, ObjectNotFoundException { i.F8
int totalRecords = userDAO.getUserCount(); ]qMH=>pOsj
if(totalRecords == 0) )*Vj3Jx
throw new ObjectNotFoundException Tfr`?:yF
\d ui`F"Cc
("userNotExist"); unJiE!
page = PageUtil.createPage(page, totalRecords); |[DV\23{G
List users = userDAO.getUserByPage(page); hi0XVC95
returnnew Result(page, users); B#Qpd7E+*
} r:.6"VQu}
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} Z$1.^H.Db
)ph30B
C~{xL>I
7^&lbzVbm(
R~!\-6%_
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 / Z1Wy-Z
'%);%y@v
询,接下来编写UserDAO的代码: dA|Lufy#
3. UserDAO 和 UserDAOImpl: !2#\| NJk
java代码: ~ t"n%SgY
)G^p1o;\
'1Y<RD>x
/*Created on 2005-7-15*/ 5d%_Wb'
package com.adt.dao; 8B_0!U&]
"wC0eDf
import java.util.List; XRtyC4f
IL2e6b
import org.flyware.util.page.Page; wG;}TxrLS
XNKtL]U}$
import net.sf.hibernate.HibernateException; g(KK9Unu
n}VbdxlN
/** %-\FVKX
* @author Joa Y'2-yB
*/ F9F" F
publicinterface UserDAO extends BaseDAO { 3>H2xh 3Y
Tw}@+-
publicList getUserByName(String name)throws j/~VP2R`
vNPfUEnA
HibernateException; 4+-5,t7
v*smI7aH
publicint getUserCount()throws HibernateException; "IOC[ #&G
)nJzSN=>$
publicList getUserByPage(Page page)throws 1bT'u5&
]"C| qR*
HibernateException; YGfA qI
y
;tXB46
} >c}:
q|R+x7x
^8b~ZX
! Zno[R
QjehDwt|
java代码: c5Z;%v |y
;_>s0rUV
b=V)?"e-
/*Created on 2005-7-15*/ CM`x>J
package com.adt.dao.impl; RA#\x.
{bW"~_6}
import java.util.List; qw6EP C
UIO6|*ka
import org.flyware.util.page.Page; ^xzE^"G6
an-\k*w
import net.sf.hibernate.HibernateException; [t {vYo
import net.sf.hibernate.Query; _e;N'DZ
O\LjtMF
import com.adt.dao.UserDAO; mipi]*ZfXE
@QvfN>T
/** 32M6EEmPG
* @author Joa un.G6| S
*/ =%Q\*xaR.W
public class UserDAOImpl extends BaseDAOHibernateImpl zNNzsT8na
eL>K2Jxq
implements UserDAO { Z'voCWCd
5Xp$yX =
/* (non-Javadoc) 9` OG
* @see com.adt.dao.UserDAO#getUserByName ,G916J*XA
jK&
Nkp
(java.lang.String) iSnIBs9\
*/ Kh>?!`lL
publicList getUserByName(String name)throws 0*37D5jH
3FGb Q_
HibernateException { #k"1wSx16
String querySentence = "FROM user in class 516VQ<