Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 p {3|W<
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 b
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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 Gx)D~7lz
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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 ]f?LQCTq<b
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分页支持类: ;k]pq 4E
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java代码: +0DIN4Y(4
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package com.javaeye.common.util; 2BY:qz%:
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import java.util.List; jL<.?HE
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publicclass PaginationSupport { KNhH4K2iP8
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publicfinalstaticint PAGESIZE = 30; lLv0lf
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privateint pageSize = PAGESIZE; sMK/l @7
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privateList items; @@ QU"8q
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privateint totalCount; `shB[Lt
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privateint[] indexes = newint[0]; TXM.,5Dx\
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privateint startIndex = 0; ^9i^Ci9
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public PaginationSupport(List items, int (ym)q#^
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totalCount){ M}>q>
setPageSize(PAGESIZE); jQhf)B
setTotalCount(totalCount); 03PVbDq-
setItems(items); =Ao;[j)*!
setStartIndex(0); I~I%z'"RQd
} F
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public PaginationSupport(List items, int ~+F: QrXcI
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totalCount, int startIndex){ 5V0=-K
setPageSize(PAGESIZE); V4>P8cE
setTotalCount(totalCount); 6`i'
setItems(items); g7pFOcV
setStartIndex(startIndex); =[,adB
} jn[a23;G)
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public PaginationSupport(List items, int ':=C2x1d|
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totalCount, int pageSize, int startIndex){ \ gN) GR
setPageSize(pageSize); |w5#a_adM
setTotalCount(totalCount); <}=D ?bXw
setItems(items); $lQi0*s
setStartIndex(startIndex); /D q]=P
}
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publicList getItems(){ P|?z1JUd
return items; >Et?7@
} U6Qeode
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publicvoid setItems(List items){ :A$6Y*s\
this.items = items; ^$(|(N[;
} BC+HP9<]
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publicint getPageSize(){ )q,}jeM8
return pageSize; :/3`+&T^/
} v#6.VUAw
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publicvoid setPageSize(int pageSize){ |lv4X}H
this.pageSize = pageSize; >@X=E3
} 1;h>^NOq
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publicint getTotalCount(){ YW5E
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return totalCount; /X?Nv^Hy
}
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publicvoid setTotalCount(int totalCount){ !"kvXxp^
if(totalCount > 0){ Fri5_rxLl
this.totalCount = totalCount; 75F&s,4+
int count = totalCount / 3"".kf,O5e
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pageSize; _eF*8 /z
if(totalCount % pageSize > 0) ,%C$~+xjM
count++; (mEZ4yM
indexes = newint[count]; IkvH8E
for(int i = 0; i < count; i++){ (Cq-8**dY
indexes = pageSize * `'93J
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} [Yv5Sw
}else{ U+ 8[Ia(t
this.totalCount = 0; g N[r*:B
} x\=h^r#w
} myo/}58Nv
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publicint[] getIndexes(){ &`9lIVB,K
return indexes; = FE,G*
} $$4% .J26Z
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publicvoid setIndexes(int[] indexes){ ~7m+cWC-+
this.indexes = indexes; CR/LV]G
} $qvNv[
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publicint getStartIndex(){ _+{s^n=
return startIndex;
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} s(dox; d
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publicvoid setStartIndex(int startIndex){ 41.+3VP
if(totalCount <= 0) a-W&/
this.startIndex = 0; ;8A_-$
elseif(startIndex >= totalCount) H$;\TG@,
this.startIndex = indexes ,"/_G
]
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[indexes.length - 1]; /; _"A)0
elseif(startIndex < 0) !>+
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this.startIndex = 0; e0qa~5
else{ :sn}D~
this.startIndex = indexes `SVR_
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[startIndex / pageSize]; 6e*JCf>
} Y,a.9AWw)
} @.5Ybgn
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publicint getNextIndex(){ Y5;:jYk#<_
int nextIndex = getStartIndex() + q q`UvU
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pageSize; /#X O!%=7
if(nextIndex >= totalCount) X2{3I\'Ft
return getStartIndex(); { sZrI5
else 0e:aeLh
return nextIndex; mMMu'N
} ?gkK*\x2
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publicint getPreviousIndex(){ 7fVVU+y
int previousIndex = getStartIndex() - ~(^[TuJC
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pageSize; $yt|nO
if(previousIndex < 0) l0
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return0; Fm@GU
else 3w-0v"j U
return previousIndex; bXJE 2N
} $q+7,,"
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} [Nq4<NK
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抽象业务类 1rN&Y,61\
java代码: Q:-/@$&i
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/** L4dbrPE*0
* Created on 2005-7-12 5/(Dh![l
*/ v\<`"
package com.javaeye.common.business; :s4CWEd
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import java.io.Serializable; wM|-u/9+
import java.util.List; UVUHLu|^
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import org.hibernate.Criteria; # ><.zZ
import org.hibernate.HibernateException; Ao,lEjN I
import org.hibernate.Session; {!,+C0
import org.hibernate.criterion.DetachedCriteria; s_]rje8`
import org.hibernate.criterion.Projections; F'"-4YV>&
import bkY7]'.bz&
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org.springframework.orm.hibernate3.HibernateCallback; Lrk^<:8;
import Xc@4(Nyp
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org.springframework.orm.hibernate3.support.HibernateDaoS "zqt'b0bW
R; IB o
upport; gDA hl
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import com.javaeye.common.util.PaginationSupport; X`22Hf4ct
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public abstract class AbstractManager extends 5$y<nMP
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HibernateDaoSupport { `W-:@?PmQx
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privateboolean cacheQueries = false; gs. K,x ma
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privateString queryCacheRegion; a MzAA
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publicvoid setCacheQueries(boolean 10a=[\ Q
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cacheQueries){ F'Wef11Yz
this.cacheQueries = cacheQueries; {}.c.W+
} Z{e5 OJ
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publicvoid setQueryCacheRegion(String 1sgoT f%
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queryCacheRegion){ *<9p88FpDU
this.queryCacheRegion = q-uYfXZ{j
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queryCacheRegion; l jNd!RaB
} #-@dc
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publicvoid save(finalObject entity){ 04,]upC${W
getHibernateTemplate().save(entity); R=E )j^<F
} ~#gVs*K
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publicvoid persist(finalObject entity){ Kyv$yf9
getHibernateTemplate().save(entity); ArF+9upGY
} k6dSj>F>
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publicvoid update(finalObject entity){ j|
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getHibernateTemplate().update(entity); {6~W2zX&
} f}@]dF r
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publicvoid delete(finalObject entity){ =!p6}5Z
getHibernateTemplate().delete(entity); YWm:#{n.
} bd%/dr
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publicObject load(finalClass entity, Qx
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finalSerializable id){ W/+|dN{O+g
return getHibernateTemplate().load ql],Wplg
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(entity, id); fIFB"toiPE
} Rk"_4zJk
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publicObject get(finalClass entity, F n6>n04v
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finalSerializable id){ 0C3CqGP
return getHibernateTemplate().get =m:0#&t,*
x; :[0(st}
(entity, id); 96 C|R
}
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publicList findAll(finalClass entity){ V-t!
return getHibernateTemplate().find("from d]+g3oy
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" + entity.getName()); u0N1+-6kr+
} 6n<:ph,h;
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publicList findByNamedQuery(finalString In]h+tG?rN
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namedQuery){ {-H6Z#b[
return getHibernateTemplate GXa-g-d
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().findByNamedQuery(namedQuery); 8sE@?,
} uGgR@+7?Z
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publicList findByNamedQuery(finalString query, V5M_N;h
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finalObject parameter){ y%iN9 -t
return getHibernateTemplate fU$zG"a_
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().findByNamedQuery(query, parameter); -<qci3Ba}
} )PR{ia64;<
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publicList findByNamedQuery(finalString query, E5.)ro=$
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finalObject[] parameters){ Nqy',N
return getHibernateTemplate nz+DPk["
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().findByNamedQuery(query, parameters); ]#_,?d
} O
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publicList find(finalString query){ :MpIx&
return getHibernateTemplate().find !*N#}6Jd
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(query); oE)tK1>;H
} YI&7s_%
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publicList find(finalString query, finalObject irpO(>LK
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parameter){ X,^J3Ek>O
return getHibernateTemplate().find _! \X>rfz
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(query, parameter); 7*uG9iX
} ^uC1\!Q1
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public PaginationSupport findPageByCriteria J?u",a]|H"
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(final DetachedCriteria detachedCriteria){ 5"k_Ms7R,
return findPageByCriteria vY6eg IO
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); NC|&7qQ
} |$^,e%bE
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public PaginationSupport findPageByCriteria 8K7zh.E
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(final DetachedCriteria detachedCriteria, finalint }[$ C=|>
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startIndex){ v~uQ_ae$>
return findPageByCriteria "\]kK@,
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(detachedCriteria, PaginationSupport.PAGESIZE, Hk(w\
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startIndex); *ofK|r
} K-(,,wS
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public PaginationSupport findPageByCriteria 9^)ochY3
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(final DetachedCriteria detachedCriteria, finalint !G Z2|~f9
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pageSize, No!P?
finalint startIndex){ ,m9Nd "6\
return(PaginationSupport) Y?R;Y:u3Z
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getHibernateTemplate().execute(new HibernateCallback(){ wnN@aO6g*
publicObject doInHibernate e#)}.
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(Session session)throws HibernateException { 5d<-y2!M
Criteria criteria = coiTVDwA
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detachedCriteria.getExecutableCriteria(session); 3@\vU~=P:
int totalCount = [AfV+$
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((Integer) criteria.setProjection(Projections.rowCount GL9R
5
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()).uniqueResult()).intValue(); o#4Wn'E
criteria.setProjection VEd\*
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(null); u,*$n'l]
List items = \/. Of]YQ
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criteria.setFirstResult(startIndex).setMaxResults :~{XL >:S
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(pageSize).list(); &B/cy<;y,
PaginationSupport ps = *<OWd'LI
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new PaginationSupport(items, totalCount, pageSize, 3T|:1Nw
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startIndex); rbqH9 S
return ps; 8~Rja
}
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}, true); 3-FS} {,
} Xb&r|pR
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public List findAllByCriteria(final Hvnak{5
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DetachedCriteria detachedCriteria){ 72@8M
return(List) getHibernateTemplate \Llrs-0 M
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().execute(new HibernateCallback(){ jgVra*
publicObject doInHibernate XCDHd
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(Session session)throws HibernateException { `[C8iF*Y"
Criteria criteria = AFc#2wn
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detachedCriteria.getExecutableCriteria(session); 7E%ehM6Y
return criteria.list(); ~2S`y=*:
} rPZ<
}, true); YEF%l'm(\
} <YUc?NF
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public int getCountByCriteria(final >Czcs=(L.k
= K"F!}
DetachedCriteria detachedCriteria){ s@'};E^]@r
Integer count = (Integer) gOx4qxy/m|
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getHibernateTemplate().execute(new HibernateCallback(){ POtDge
publicObject doInHibernate P zzX Ds6
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(Session session)throws HibernateException { L` V6\Ix(I
Criteria criteria = C;OU2,c,T
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detachedCriteria.getExecutableCriteria(session); YL;ZZ2A
return @lc1Ipfk"
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criteria.setProjection(Projections.rowCount nsaf6y&E
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()).uniqueResult(); .]k(7F!W
} %Jq(,u
}, true); q}M^i7IE
return count.intValue(); C'
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} ^8
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} 'i%Azzv
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用户在web层构造查询条件detachedCriteria,和可选的 Rqa#;wb!(
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Yc"G="XP;
u)t1t69T\g
PaginationSupport的实例ps。 #ie{!Mh
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ps.getItems()得到已分页好的结果集 &+J5GHt@
ps.getIndexes()得到分页索引的数组 F<Z"W}I+6
ps.getTotalCount()得到总结果数 nR!qolh
ps.getStartIndex()当前分页索引 )
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ps.getNextIndex()下一页索引 tJ&S&[}
ps.getPreviousIndex()上一页索引 H_o<!YxK
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 $_S^Aw?
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 bO9F rEz5
:kOLiko!4>
一下代码重构了。 oMkB!s
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我把原本我的做法也提供出来供大家讨论吧: :uu\q7@'
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首先,为了实现分页查询,我封装了一个Page类: AZI%KM[
java代码: pn{.oXomf
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/*Created on 2005-4-14*/ 8ftLYMX@
package org.flyware.util.page; rQ30)5^V|
:*/<eT_
/** gG*O&gQY
* @author Joa ucJR #14
* @ns2$(wkm@
*/ /fBZRdB
publicclass Page { wI#rAx7f-
ky#<\K1}'
/** imply if the page has previous page */ 3543[W#a
privateboolean hasPrePage; <*8nv.PX*
0 m";=:(w
/** imply if the page has next page */ `w[0q?}"`
privateboolean hasNextPage; FGy7KVR
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/** the number of every page */ m&Ms[X
privateint everyPage; qWw@6VvoQ
)n5]+VTZ5
/** the total page number */ N95"dNZE
privateint totalPage; U87VaUr
*h@nAB\3
/** the number of current page */ <saS2.4
privateint currentPage; C/<fR:`c
v srce
/** the begin index of the records by the current ;s9!ra:3
X'7 T" 5!
query */ cK@O)Ko}
privateint beginIndex; %nFZA)B[
gS4K](KH |
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/** The default constructor */ 31w?bx !Pp
public Page(){ yc_(L-'n
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} h+R}O9BD
g#Zb}^
/** construct the page by everyPage ,y:q]PR
* @param everyPage }b)?o@9}:
* */ Pkc4=i,`A
public Page(int everyPage){ |os2@G$
this.everyPage = everyPage; xotq$r
} M}(4>W
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/** The whole constructor */ R?Iv<(I
public Page(boolean hasPrePage, boolean hasNextPage, $v-lG(
&fiDmUxj
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int everyPage, int totalPage, '9$xOrv
int currentPage, int beginIndex){ B,e@v2jO|
this.hasPrePage = hasPrePage; kki]6_/n
this.hasNextPage = hasNextPage; P:ys--$"
this.everyPage = everyPage; V0wK.^]+}/
this.totalPage = totalPage; }9 qsPn
this.currentPage = currentPage; XO"!)q F
this.beginIndex = beginIndex; #uu wzE*M_
} }gag?yQ.^
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/** /e4hB
* @return _ky!4^B
* Returns the beginIndex. 0kmVP~K
*/ ~4XJ" d3L
publicint getBeginIndex(){ <%qbU-
return beginIndex; 9#O"^.Z !
} "%,zB_ng\<
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/** e] **Z,Z
* @param beginIndex c6BaC@2
* The beginIndex to set. *5*d8;@>
*/ FZjtQ{M
publicvoid setBeginIndex(int beginIndex){ k}F ;e_
this.beginIndex = beginIndex; (a&.Ad0{
} Ev*HH+:b>
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/** KXicy_@DC`
* @return B<8Z?:3YS
* Returns the currentPage. [#lPT'l
*/ DFE?H
publicint getCurrentPage(){ @@SG0YxZ
return currentPage; zVl(?b&CF
} u^!-Z)W
y])xP%q2O
/** k3S**&i!CR
* @param currentPage pg4M$;ED
* The currentPage to set. Kc{fT^E
*/ m"H9C-Y
publicvoid setCurrentPage(int currentPage){ Xa9G;J$
this.currentPage = currentPage; +~w '?vNc
} Q?W]g%:)
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/** 7F)HAbIS
* @return h %MPppCEa
* Returns the everyPage. ?>4^e:
*/ .$99/2[90
publicint getEveryPage(){ uh:
return everyPage; |{t}ULc
} %ze Sx
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% %
/** ',J3^h!b
* @param everyPage PuUqWW'^
* The everyPage to set. cN&b$8O=%
*/ y$4,r4cmR|
publicvoid setEveryPage(int everyPage){ ]C5JP~#z
this.everyPage = everyPage; O2 3f\pm&
} vERsrg;(
z'fGHiX7.0
/** crZ\:LeJ
* @return (doFYF~w
* Returns the hasNextPage. G>*s+
*/ 1eiH%{w
publicboolean getHasNextPage(){ i]9SCO
return hasNextPage; Hr96sN.R
} i>b^n+74>
/F/`?=1<$
/** 9-}&znLZe
* @param hasNextPage /PHktSG
* The hasNextPage to set. {#>@h7
*/ lt}|Y9h
publicvoid setHasNextPage(boolean hasNextPage){ G^r^" j
this.hasNextPage = hasNextPage; LB 2
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} 4i/ TEHQ
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/** {%UY1n
* @return @}aK\
* Returns the hasPrePage. Yx
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*/ 78 }iNGf
publicboolean getHasPrePage(){ E
hd*
return hasPrePage; X Uh)z
} O6k[1C
HYW+,ts'
/** 1Voo($q.
* @param hasPrePage ]2K>#sn-]
* The hasPrePage to set. f8'&(-
*/ B6$s*SXNp
publicvoid setHasPrePage(boolean hasPrePage){ ]yCmGt+b
this.hasPrePage = hasPrePage; }b6ja y
} b>I -4
$~ zqt%}
/** r(i<H%"Z
* @return Returns the totalPage. M7!&gFv8
* (w"zI!
*/ d3^LalAp
publicint getTotalPage(){ Ha4?I$'$
return totalPage; Hdj0! bUx
} Hsx`P
Z*s/%4On
/** _3hCu/BV
* @param totalPage kTs)u\r.
* The totalPage to set. :~U1JAs$
*/ !=k\Rr@qx
publicvoid setTotalPage(int totalPage){ cs~
}k7><
this.totalPage = totalPage; |wVoJO!O}
} UI>-5,X
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} \=,+weGw@
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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 lE=Q(QUr
(VwS9:`
个PageUtil,负责对Page对象进行构造: /EKfL\3
java代码: Dzc 4J66
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/*Created on 2005-4-14*/ ^'v6
,*:4
package org.flyware.util.page;
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import org.apache.commons.logging.Log; 8m-jU
5u
import org.apache.commons.logging.LogFactory; M8S4D&vpD4
fs>0{
/** lKH"PH7*_w
* @author Joa u+th?KO`
* |WubIj*\{
*/ ?ix0n,m
publicclass PageUtil { QF[9Zn
q w|M~vdm
privatestaticfinal Log logger = LogFactory.getLog EzzzH(!j
3)42EM'9(
(PageUtil.class); -^\k+4;
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/** i!YZF$|
* Use the origin page to create a new page +zz9u?2C`
* @param page MeP U`M--
* @param totalRecords q)<5&|V
* @return 9c#9KCmc
*/ "Z}0 A/y
publicstatic Page createPage(Page page, int #; }IHAR
V/>SjUNq
totalRecords){ v`x~O+
return createPage(page.getEveryPage(), EX8]i,s|E
7fnKe2MM
page.getCurrentPage(), totalRecords); |]r# IpVf
} $@8\9Y
{
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/** 3]xnKb|W
* the basic page utils not including exception +=u*!6S
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handler br$!}7#=L
* @param everyPage bis/Nfr]
* @param currentPage iWQBo>x
* @param totalRecords 3S'V>:
* @return page R%3H"FU9w
*/ |W*f6F3
publicstatic Page createPage(int everyPage, int !!Mp;h'}-
#8nF8J<4
currentPage, int totalRecords){ 9OT2yCT
everyPage = getEveryPage(everyPage); jnH44
currentPage = getCurrentPage(currentPage); h/-7;Csv
int beginIndex = getBeginIndex(everyPage, kFD-
YF&SH)Y7
currentPage);
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int totalPage = getTotalPage(everyPage, ,,BNUj/:
lh?mN3-*
totalRecords); 0FTiTrTn
boolean hasNextPage = hasNextPage(currentPage, y~ ^>my7G
*;"^b\f5_
totalPage); K"-N:OV
boolean hasPrePage = hasPrePage(currentPage); v6f$N+4c
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returnnew Page(hasPrePage, hasNextPage, #c/v2
everyPage, totalPage, #)cRD#0
currentPage, Im6ymaf9
HT1bsY
0t
beginIndex); U@Aq@d+n
} +zL=UEBN
X<-]./
privatestaticint getEveryPage(int everyPage){ H,3$TNXy
return everyPage == 0 ? 10 : everyPage; vc^PXjX
} 9Cf^Q3)5o
kQVl8KS
privatestaticint getCurrentPage(int currentPage){ ;F~GKn;}
return currentPage == 0 ? 1 : currentPage; ;;l(
} .=^h@C*
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privatestaticint getBeginIndex(int everyPage, int 9h*$P:S;1v
z:<(b
currentPage){ ?]h+En5z8
return(currentPage - 1) * everyPage; 2$1rS}}
} Ej.D!@
* k=L
privatestaticint getTotalPage(int everyPage, int 0Vy*
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hi
totalRecords){ ~xvQ?c?-
int totalPage = 0; fCEd
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if(totalRecords % everyPage == 0) TTy1a:V
totalPage = totalRecords / everyPage; z$;%SYI
else lD C74g
totalPage = totalRecords / everyPage + 1 ; {-17;M$
a-%^!pN\M
return totalPage; cJE2z2uW0
} `5GJ,*{z
!lu$WJ{M
privatestaticboolean hasPrePage(int currentPage){ Z|wZyt$$
return currentPage == 1 ? false : true; *+@/:$|U
} 7*[>e7:A
6e~+@S
privatestaticboolean hasNextPage(int currentPage, j&8 ~X2?*
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int totalPage){ If4YqBG
return currentPage == totalPage || totalPage == M6DyOe<
G9VzVx#T#
0 ? false : true; CqrmdWN
} cRU.
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} eh)J'G]G
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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。 1N#TL"lMS
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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 w_|WberU
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做法如下: 7c;59$2(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;\#u19
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的信息,和一个结果集List:
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java代码: ^OA}#k
NTW
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a`|/*{
/*Created on 2005-6-13*/ W%1fm/G0
package com.adt.bo; *O 0*
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import java.util.List; K5w22L^=+
r0S7e3xb
import org.flyware.util.page.Page; y8<,>
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/** 8Q6il-
* @author Joa \sRRLDj%
*/ spe9^.SI
publicclass Result { c~C :"g.y
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private Page page; n+!.0d}6
=#+Z KD
private List content; Fg,[=CqB[
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/** :fj}J)9'xW
* The default constructor |]m&LC
*/ I1}{7-_t
public Result(){ jN*A"m
super(); YJ75dXc&&
} 7q67_u?@
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/** [e&$4l IS
* The constructor using fields iK.MC%8?
* |Ec $%
* @param page 4&$G;?#W2
* @param content ^|sQkufo
*/ fqZ!Bi
public Result(Page page, List content){ 2{#quXN9
this.page = page; _nTjCN625
this.content = content; ]1Q\wsB
} h.7 1O"N
atN`w=6A`
/** ;yUY|o
* @return Returns the content. }e@j(*8
*/ {+r?g J
publicList getContent(){ \T[*|"RFZ
return content; 5T;_k'qe
} Y.hrU*[J0
>c1mwZS;
/** Az)P&*2:'`
* @return Returns the page. UPgZj\t%{
*/ }$UuYO/i
public Page getPage(){ =ecv;uu2
return page; ?]7ITF
} [&zP$i&
A+
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/** -J[D:P.Z
* @param content ;pU LJ}rDb
* The content to set. 60p1.;'/a
*/ $h$+EE!
public void setContent(List content){ (te\!$
this.content = content; %WO;WxG8^
} YqDw*S{
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/** ZU:gNO0
* @param page Sqb#U{E
* The page to set. @lmk e>
*/ rSZWmns
publicvoid setPage(Page page){ y'+^
ME$H
this.page = page; Et- .[
} ,O-lDzcw
} ,:v}gS?Uq
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leD?yyjw7
2. 编写业务逻辑接口,并实现它(UserManager, v\HGL56T
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UserManagerImpl) G_o/ lIz"
java代码: M)LdGN?$
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(Q'XjN\#
/*Created on 2005-7-15*/ iD]!PaFD`
package com.adt.service; {<]abO
JZ c5U}i
import net.sf.hibernate.HibernateException; gWlmQl
kB8l`|
I
import org.flyware.util.page.Page; l,/5$JGnk
?Rwn1.Z
import com.adt.bo.Result; fDRQ(}
6-JnT_
/** PCU6E9~t2
* @author Joa O-G@To3\
*/ ooD/QZUE
publicinterface UserManager { Y Jv{Z^;M
eIEcj<f
public Result listUser(Page page)throws b"zq3$6*
r|#4+'
HibernateException; 0P)c)x5
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} T|}HK]QOX
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j`#|z9`(pB
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java代码: {:rU5 !n
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/*Created on 2005-7-15*/ G%>[I6G
package com.adt.service.impl; ~+d]yeDrhx
@9L%`=]b^
import java.util.List; @4Y>)wn&;
p*N+B
o
import net.sf.hibernate.HibernateException; i&l$G55F
:4;>).
import org.flyware.util.page.Page; R<wb8iir
import org.flyware.util.page.PageUtil; "W1 q}4_
<oeHZD_OR
import com.adt.bo.Result; `P GWu1/
import com.adt.dao.UserDAO; k!%HcU%J
import com.adt.exception.ObjectNotFoundException; Qr0GxGWU
import com.adt.service.UserManager;
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/** Vk-_v5
* @author Joa ;lK2]
*/ .*,Zh2eXU
publicclass UserManagerImpl implements UserManager { /bw-*
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private UserDAO userDAO; ";zl6g"
S#""((U$
/** B(>_.x#kv
* @param userDAO The userDAO to set. !Q?4sAB
*/ cJty4m-
publicvoid setUserDAO(UserDAO userDAO){ 7'<4'BGzl]
this.userDAO = userDAO; 6)?TWr'K e
} Dg]i};
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/* (non-Javadoc) EdU3k'z$
* @see com.adt.service.UserManager#listUser yn=1b:kid
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(org.flyware.util.page.Page) 85X^T]zo
*/ qItI):9U
public Result listUser(Page page)throws @hv9=v+
0lBl5ke
HibernateException, ObjectNotFoundException { IAtZ-cM<
int totalRecords = userDAO.getUserCount(); tC&y3!k2jR
if(totalRecords == 0) HnpGPGz@F
throw new ObjectNotFoundException 9R E;50h
Xau.4&\d
("userNotExist"); 1ri#hm0x\
page = PageUtil.createPage(page, totalRecords); )dvOg'it
List users = userDAO.getUserByPage(page); C=Zuy^
returnnew Result(page, users); _}\&;
} \Z~m6;
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} M,[ClQ 9
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Sj*H4ZHD<&
9V;m;sz
TX
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <6`,)(dj
EXzY4D ^
询,接下来编写UserDAO的代码: Vt&I[osC
3. UserDAO 和 UserDAOImpl: _l Jj 6=
java代码: i<T`]g
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68d @By
/*Created on 2005-7-15*/ Zaj<*?\
package com.adt.dao; vD*KJ3(c
m]%cNxS
import java.util.List; ;J_d%
7z$+ *]9-
import org.flyware.util.page.Page; c9&
8kq5
u|Ai<2b$
import net.sf.hibernate.HibernateException; Wl,yznT
x
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/** H#ihU3q
* @author Joa 6yR7RF}
*/ *zx;81X=
publicinterface UserDAO extends BaseDAO { 7j]@3D9[:p
6ZM<M7(V
publicList getUserByName(String name)throws Z]6D0b
$@<