Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Z<|caT]Q(
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 56o?=|
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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 &Sc}3UI/F
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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 y= ILA
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分页支持类: EYUr.#:
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java代码: 1GW=QbO 6
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package com.javaeye.common.util; )*^PMf
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import java.util.List; h"YIAQ',
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publicclass PaginationSupport { ZBJYpeGe
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publicfinalstaticint PAGESIZE = 30; eR8qO"%2:
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privateint pageSize = PAGESIZE; (G"b)"Qum
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privateList items; EG0NikT?
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privateint totalCount; j*$GP'Df3
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privateint[] indexes = newint[0]; oa`,|dA"
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privateint startIndex = 0; -Tk~c1I#`
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public PaginationSupport(List items, int @yB!? x
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totalCount){ tGD$cBE
setPageSize(PAGESIZE); 0ldde&!p
setTotalCount(totalCount); g?i_10Xlp
setItems(items); `a2Oj@jP
setStartIndex(0); C>@~W(IE
} g=[ F W@z
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public PaginationSupport(List items, int Eln"RKCt}9
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totalCount, int startIndex){ S]1+tj
setPageSize(PAGESIZE); &tQ,2RT
setTotalCount(totalCount); s+^o[R
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setItems(items); Qkk~{OuC
setStartIndex(startIndex); ,+*8@>c
} r,MgIv(L
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public PaginationSupport(List items, int t_,iV9NrZ
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totalCount, int pageSize, int startIndex){ q`}Q[Li
setPageSize(pageSize); f<WnPoV
setTotalCount(totalCount); OV>T}Fq
setItems(items); VPn#O
setStartIndex(startIndex); K~@-*8%
} X&M4c5Li
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publicList getItems(){ Sd^e!?bp
return items; ,h5.Si>
} Roy`HU
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publicvoid setItems(List items){ Q_6./.GQ
this.items = items; P}&7G-
} 0} liK
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publicint getPageSize(){ ozkN&0
return pageSize; rgIJ]vmy<H
} J}`K&DtM9
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publicvoid setPageSize(int pageSize){
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this.pageSize = pageSize; @w6^*Z_hQ
} [CRy>hfV
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publicint getTotalCount(){ jfqWcX.X=
return totalCount; XT~JP
} ;b
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publicvoid setTotalCount(int totalCount){
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if(totalCount > 0){ .XURI#b
this.totalCount = totalCount; <pYGcVB9V
int count = totalCount / zi[bpa17W
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pageSize; t wtGkkC
if(totalCount % pageSize > 0) A0O$B7ylQ
count++; V[+ Pb]
indexes = newint[count]; >V87#E
for(int i = 0; i < count; i++){ -&))$h3o\
indexes = pageSize * AUS?Pt[w
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} l%fnGe` _
}else{ StP6G ]x
this.totalCount = 0; 0NpxqeIDY
} 1.yw\ZC\
} _h@7>+vl~
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publicint[] getIndexes(){ <B$Lu4b@c
return indexes; 9S&6u1
} _*bXVJ
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publicvoid setIndexes(int[] indexes){ t}nZrD
this.indexes = indexes; IH[/fd0
} f:"es: Fb
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publicint getStartIndex(){ A>7'W\R
return startIndex; pK*-In
} \RMYaI^+;
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publicvoid setStartIndex(int startIndex){ EW#.)@-
if(totalCount <= 0) 9N=Dls
this.startIndex = 0; #1u4Hi(x5
elseif(startIndex >= totalCount) ,!%[CpM3
this.startIndex = indexes 4(u+YW GX
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[indexes.length - 1]; |%&WYm6
elseif(startIndex < 0) jW2z3.w
this.startIndex = 0; 1/gY]ghL
else{ WF *2^iWJ
this.startIndex = indexes 4w]u: eU
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[startIndex / pageSize]; O~fRcf:Q
} ,a^_
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} biKpV?Dp
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publicint getNextIndex(){ /o8`I
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int nextIndex = getStartIndex() + [^ 7^&/0
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pageSize; W.zA1S
if(nextIndex >= totalCount) 4X#>;
return getStartIndex(); ,589/xTA@
else z56W5g2
return nextIndex; _QY0j%W
} 2c8,H29
*1; <xeVD
publicint getPreviousIndex(){ G-M!I`P
int previousIndex = getStartIndex() - {l *ps-fi
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pageSize; y<)Lr}gP
if(previousIndex < 0) JkQ4'$:
return0; ! ~&X1,l1*
else gA~Ih
return previousIndex; oPzt1Y
} fcJ#\-+E
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} ;EL!TzL:8
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抽象业务类 tBrd+}e2*
java代码:
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/** <0R?#^XBZB
* Created on 2005-7-12 u^ngD64
*/ x0Tb7y`
package com.javaeye.common.business; iKp4@6an
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import java.io.Serializable; N1#*~/sXh
import java.util.List; $D9JsUij
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import org.hibernate.Criteria; 20% xD e
import org.hibernate.HibernateException; Gtg;6&2
import org.hibernate.Session; er l_Gg
import org.hibernate.criterion.DetachedCriteria; :Q?xNY%
import org.hibernate.criterion.Projections; P-^Z7^o-bX
import \zj8| +
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org.springframework.orm.hibernate3.HibernateCallback; qMI%=@=
import !^l<jrM
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org.springframework.orm.hibernate3.support.HibernateDaoS )
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upport; V-7!)&q
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import com.javaeye.common.util.PaginationSupport; +Icg;m{
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public abstract class AbstractManager extends L2Gm0 v
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HibernateDaoSupport { =H!u4
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privateboolean cacheQueries = false; }p8a'3@Z
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privateString queryCacheRegion; g~10K^
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publicvoid setCacheQueries(boolean evimnV
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cacheQueries){ 17<\Q(YQ=
this.cacheQueries = cacheQueries; }4eSB
} ajkRL|^
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publicvoid setQueryCacheRegion(String v
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queryCacheRegion){ gfih;i.pY
this.queryCacheRegion = AO8`ItNZdT
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queryCacheRegion; #1V vK
} <5C3c&sds
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publicvoid save(finalObject entity){ }ZvL%4jT
getHibernateTemplate().save(entity); Bz7T1B&to
} ^(UL$cQ>
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publicvoid persist(finalObject entity){ -] J V
getHibernateTemplate().save(entity); Mg^GN-l
} Q !S"=2
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publicvoid update(finalObject entity){ \'E%ue_<9
getHibernateTemplate().update(entity); /0"Y.
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} /o8h1L=
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publicvoid delete(finalObject entity){ ";s?#c
getHibernateTemplate().delete(entity);
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} @uT\.W:Q2
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publicObject load(finalClass entity, f&{2G2O%
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finalSerializable id){ p jHUlQ
return getHibernateTemplate().load .rN5A+By`
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(entity, id); ;wTl#\|w0
} m./lrz
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publicObject get(finalClass entity, )ZNH/9e/
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finalSerializable id){ mjS)*@F
return getHibernateTemplate().get k\x>kJ}0
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(entity, id); /lAt&0
} r+v*(Tu
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publicList findAll(finalClass entity){ 3VALrb;
return getHibernateTemplate().find("from m:Z=: -x
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" + entity.getName()); -i?!em'J
} SaQ_%-p
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publicList findByNamedQuery(finalString JBi<TDm/
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namedQuery){ )Hl;9
return getHibernateTemplate SvDVxK
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().findByNamedQuery(namedQuery); H%Q@DW8~@
} #N@sJyIN
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publicList findByNamedQuery(finalString query, ~~:i+-[
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finalObject parameter){ 4J-)+C/edx
return getHibernateTemplate K^s!0[6
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().findByNamedQuery(query, parameter); i<)c4
} N`8?bU7a}"
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publicList findByNamedQuery(finalString query, [g_f`ZJ=
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finalObject[] parameters){ gWgYZX
return getHibernateTemplate '$q'Wl)
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().findByNamedQuery(query, parameters); im4V6 f;%
} 9[6xo!
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publicList find(finalString query){ \7*9l%
return getHibernateTemplate().find f>-OwL($P
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(query); lj'c0k8
} )#IiHBF
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publicList find(finalString query, finalObject >Y)jt*vQ
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parameter){ mi%d([)%<
return getHibernateTemplate().find 'S E%9
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(query, parameter); SDDs}mV
} 8WfF: R;
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public PaginationSupport findPageByCriteria hY/SR'8
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(final DetachedCriteria detachedCriteria){ ~*THL0]~
return findPageByCriteria G5bi,^G7
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); C&Ow*~
} [1 w
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public PaginationSupport findPageByCriteria 8O("o7~"
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(final DetachedCriteria detachedCriteria, finalint .+|G`*1<i
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startIndex){ pkjL2U:
return findPageByCriteria :}o0Eb
)?I1*(1{A
(detachedCriteria, PaginationSupport.PAGESIZE, a?M<r>
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startIndex); c*HS#C7'2
} s)]i0+!
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public PaginationSupport findPageByCriteria y 3c]zDjV
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(final DetachedCriteria detachedCriteria, finalint .kBi" p&
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pageSize, @,pO%,E6
finalint startIndex){ kIP~XV~
return(PaginationSupport) b ]1SuL
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getHibernateTemplate().execute(new HibernateCallback(){ dkLc"$(O
publicObject doInHibernate *N[.']#n
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(Session session)throws HibernateException { Y>wpla[kUq
Criteria criteria = 6./h0kD`
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detachedCriteria.getExecutableCriteria(session); bx!Sy0PUJ
int totalCount = ZRsDn
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((Integer) criteria.setProjection(Projections.rowCount
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()).uniqueResult()).intValue(); v^HDR 3I
criteria.setProjection = 14'R4:
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(null); it D%sKo
List items = {~[H"h537t
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criteria.setFirstResult(startIndex).setMaxResults "|.>pD#0&
f|w+}z
(pageSize).list(); .A&Ey5
PaginationSupport ps = [
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new PaginationSupport(items, totalCount, pageSize, NnGQ=$e
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startIndex); $ 6Nm`[V
return ps; $/Zsy6q:
} zf5s\w.4
}, true); _+wv3?
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} 8Rc4+g
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public List findAllByCriteria(final `jvIcu5c
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DetachedCriteria detachedCriteria){ D2[uex
return(List) getHibernateTemplate )wCA8
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().execute(new HibernateCallback(){ @HMt}zD
publicObject doInHibernate aluXh?
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(Session session)throws HibernateException { j K$4G.x
Criteria criteria = HI,1~Jw+
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detachedCriteria.getExecutableCriteria(session); Yw\}'7
return criteria.list(); ?G*XZ0u~
} I&q:w\\z8|
}, true); z%`Tf&UL
} 1LJ
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public int getCountByCriteria(final G>YJ3p7
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DetachedCriteria detachedCriteria){ ;6e#W!
Integer count = (Integer) )j',e$m
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getHibernateTemplate().execute(new HibernateCallback(){ gTH1FR8$y
publicObject doInHibernate 1AjsAi,7;2
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(Session session)throws HibernateException { C ])Q#!D|
Criteria criteria = e ! 6SJ7xC
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detachedCriteria.getExecutableCriteria(session); `[jQn;
return $io-<Z#Q
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criteria.setProjection(Projections.rowCount LCyci1\@
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()).uniqueResult(); 23_<u]V
} c^6v7wT5
}, true); e,Gv~ae9
return count.intValue(); G"5Nj3vd
} 6@]Xwq
} Q2Yv8q_}Uq
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用户在web层构造查询条件detachedCriteria,和可选的 d?v#gW
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Ke&lGf"5
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PaginationSupport的实例ps。 @1*lmFq'kV
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ps.getItems()得到已分页好的结果集 k]qZOO}
ps.getIndexes()得到分页索引的数组 2 8f-8B
ps.getTotalCount()得到总结果数 5caYA&R
ps.getStartIndex()当前分页索引 N>/*)Frt
ps.getNextIndex()下一页索引 p87s99
ps.getPreviousIndex()上一页索引 T
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Dr6Br<yi
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 N5}vy$t_P
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一下代码重构了。 mIFS/C
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我把原本我的做法也提供出来供大家讨论吧: 6 KnD(im
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首先,为了实现分页查询,我封装了一个Page类: >, 234ab=d
java代码: )@]-bPnv
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/*Created on 2005-4-14*/ thipfS
package org.flyware.util.page; %f6l"~y
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/** 7 z<!2
* @author Joa /nv1.c)k
* [O"i!AQ
*/ 2O<Sig=
publicclass Page {
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/** imply if the page has previous page */ F#X\}MvEU
privateboolean hasPrePage; L9Fx
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/** imply if the page has next page */ p\+#`] Q7}
privateboolean hasNextPage; /D1Bf:'(
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/** the number of every page */ ,=$yvZs4[]
privateint everyPage; _\@i&3hkx
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/** the total page number */ <Cg;l<$`b
privateint totalPage; ]DmqhK`
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/** the number of current page */ +
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privateint currentPage; 45kMIh~~X
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/** the begin index of the records by the current Vq9hAD|k
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query */ mKe{y.
privateint beginIndex; Ic#+*W\ZW
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/** The default constructor */ Kw!`u^>
public Page(){ *9PS2*n
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} m+OR W"o
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/** construct the page by everyPage }Lb];hww1
* @param everyPage Wv=L_E_
* */ ,Yi =s;E
public Page(int everyPage){ I=(O,*+PQ
this.everyPage = everyPage; :6HMb^4
} JYv&I t
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/** The whole constructor */ CvbY2_>Nh
public Page(boolean hasPrePage, boolean hasNextPage, ec=4L@V*
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int everyPage, int totalPage, ZN1QTb
int currentPage, int beginIndex){ {GHGFi`Z
this.hasPrePage = hasPrePage; yt!K|g
this.hasNextPage = hasNextPage; f1=8I_>=
this.everyPage = everyPage; uUc[s"\
this.totalPage = totalPage; -F8%U:2a
this.currentPage = currentPage; 3g-}k
this.beginIndex = beginIndex; tCc}}2bC&
} h$ZF[Xbfe
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/** 1d\K{ 7i#
* @return }}_WZ},h
* Returns the beginIndex. B5I(ai7<M
*/ ;H:qDBH
publicint getBeginIndex(){ c#HocwP@
return beginIndex; 3>L1}zyM]
} L {B#x@9tQ
L"}@>&6
/** lPFMNRt~8
* @param beginIndex /f# rN_4
* The beginIndex to set. U]R7=
*/ *Gu=O|Mm
publicvoid setBeginIndex(int beginIndex){ l@j!j]nE
this.beginIndex = beginIndex; k?J}-+Bm[|
} @F3 d9t-
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/** |?g2k:fzB7
* @return BwEL\*$g
* Returns the currentPage. W]M[5p]*
*/ N#[/h96F
publicint getCurrentPage(){ JBoo7a1
return currentPage; <n6/np!
} U{ahA
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/** Qz$.t>@V=
* @param currentPage YO,GZD`-o
* The currentPage to set. E&[ox[g{
*/ M2oKLRt)L
publicvoid setCurrentPage(int currentPage){ ait/|a
this.currentPage = currentPage; QkF-}P%
} eGguq~s`
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/** P AKh v.7
* @return }>0UaK
* Returns the everyPage. [xE\IqwM
*/ [6/%ynlP
publicint getEveryPage(){ ;$%+TN
return everyPage;
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} aqyXxJS8
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/** p1|@F^Q
* @param everyPage H>Fy 2w
* The everyPage to set. CV&
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*/ $hE X,
publicvoid setEveryPage(int everyPage){ Wo2M}]0
this.everyPage = everyPage; h[lh01z
} >5 i8%r
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/** #v~5f;[AAs
* @return 9JUlu
* Returns the hasNextPage. #K4wO!d
*/ 6'Lij&,f?{
publicboolean getHasNextPage(){ 7M$>'PfO
return hasNextPage; T
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} FJ2^0s/"
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/** 3F4I{L
* @param hasNextPage |H
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* The hasNextPage to set. sXfx[)T<
*/ k*n5+[U^tP
publicvoid setHasNextPage(boolean hasNextPage){ =XWi+')
this.hasNextPage = hasNextPage; =nY*,Xu<
} YHAy+S
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/** \y0abxIHS
* @return U,+=>ns>
* Returns the hasPrePage. +q=/}|
*/ >yL8C:J9
publicboolean getHasPrePage(){ cy}2~w&s4
return hasPrePage; N:d" {k
} f-23.]`v
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/** qvab>U`
* @param hasPrePage \
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* The hasPrePage to set. Tlf G"HzZ%
*/ 43(+3$V M7
publicvoid setHasPrePage(boolean hasPrePage){ N}^\$sVu_
this.hasPrePage = hasPrePage; G,$jU9 f
} C"YM"9JSJ
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/** mk0rAN
* @return Returns the totalPage. N2x\O~7
* -ff*,b$Q/
*/ #PFf`7b,z
publicint getTotalPage(){ ,I)/ V>u
return totalPage; ?p}m[9@
} mT)iN`$Y@
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/** fwOvlD&e
* @param totalPage ]^.#d
* The totalPage to set. jLZ~9FXF2
*/ Bh@j6fv
publicvoid setTotalPage(int totalPage){ N]5-#
this.totalPage = totalPage; !rwv~9I
} //AS44^IS
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} !qy/'v4
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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 %pV/(/Q
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个PageUtil,负责对Page对象进行构造: f4:gD*YT
java代码: /tV)8pEj
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/*Created on 2005-4-14*/ fpzC#
package org.flyware.util.page; b~cN#w
#
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import org.apache.commons.logging.Log; b^FB[tZ\x
import org.apache.commons.logging.LogFactory; :~g=n&x
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/** +e4o~p
* @author Joa S^~GI$
* iGm[fxQ|
*/ e6]u5;B
r
publicclass PageUtil { mO]>(^c
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privatestaticfinal Log logger = LogFactory.getLog LL.YkYu
q(_pk&/
(PageUtil.class); ULAAY$o@5
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/** KLlW\MF1
* Use the origin page to create a new page *qGxQ?/
* @param page j@Z4(XL
* @param totalRecords ,GGr@})
* @return lS9rgq<n
*/ P b2exS(
publicstatic Page createPage(Page page, int V[Auw3)
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totalRecords){ )CEfG
return createPage(page.getEveryPage(), ~x`OCii
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page.getCurrentPage(), totalRecords); <+pwGKtD
} l *.#g
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/**
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* the basic page utils not including exception leX&py
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E
handler r#3(;N{=
* @param everyPage ;#cb%e3
* @param currentPage #(T
* @param totalRecords A2g+m
* @return page g!cTG-bh>J
*/ TDk'
publicstatic Page createPage(int everyPage, int z4{H=
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currentPage, int totalRecords){ jBarY g
everyPage = getEveryPage(everyPage); ,;hIyT
currentPage = getCurrentPage(currentPage); 6:#zlKYJ
int beginIndex = getBeginIndex(everyPage, i4&"-ujrm
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currentPage); F3i+t+Jt
int totalPage = getTotalPage(everyPage, Hq3"OMG q
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totalRecords); q:+,'&<D
boolean hasNextPage = hasNextPage(currentPage, $62!R]C9\
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totalPage); (n|PLi
boolean hasPrePage = hasPrePage(currentPage); (%YFcE)SRS
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returnnew Page(hasPrePage, hasNextPage, -]\UFR
everyPage, totalPage, v&D^N9hy9
currentPage, tc.R(F96
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beginIndex); u-$(TyDEl|
} vzd1:'^t
$&I##od
privatestaticint getEveryPage(int everyPage){ S{zi8Oc6
return everyPage == 0 ? 10 : everyPage; I_oJx
} Cpz'6F^oP
D({%FQ"
privatestaticint getCurrentPage(int currentPage){ }v"X.fa^
return currentPage == 0 ? 1 : currentPage; :na9PW`TC
} C%9;~S
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privatestaticint getBeginIndex(int everyPage, int JUt
7
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currentPage){ # 4L[8(+V
return(currentPage - 1) * everyPage; yn)K1f^
} L
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privatestaticint getTotalPage(int everyPage, int L#1YR}m
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totalRecords){ s=h
int totalPage = 0; '%vb&a!.6
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if(totalRecords % everyPage == 0) bx_`S#*N
totalPage = totalRecords / everyPage; NiQ`,Q$B
else ?|s1Cuc
totalPage = totalRecords / everyPage + 1 ; [I^>ji0V
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return totalPage; l\I#^N
} `lX |yy"
*Fi`o_d9[`
privatestaticboolean hasPrePage(int currentPage){ /'ccFm2
return currentPage == 1 ? false : true;
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} 7Ps I'1v
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privatestaticboolean hasNextPage(int currentPage, M_<O'Ii3
meA=lg?
int totalPage){ ,]+P#eXgE
return currentPage == totalPage || totalPage == 4C\>JGZvq
}(4U7Ac
0 ? false : true; ]h3<r8D_#
} S='AA_jnw
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} 3(0k!o0"
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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。 a|Io)Qhr
eKPxSN Z
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 z-$ bce9*
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做法如下: +P:xB0Tm
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1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?-1r$z
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的信息,和一个结果集List: KCu @5`p
java代码: =NMT H[
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/*Created on 2005-6-13*/ (99P9\[p
package com.adt.bo; |\;oFuCv##
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import java.util.List; v]SHude{
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import org.flyware.util.page.Page; WDQtj$e+
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/** {|nm0vg`A
* @author Joa ^}7iouE C
*/ 5#3/
publicclass Result { J6J[\
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private Page page; $fES06%
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private List content; 3C'`K,
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/** ;43Ye
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* The default constructor VrLU07"0n
*/ ~b;l08 <
public Result(){ D1]%2:
super(); H'7AIY}
} 8s(?zK\
q_S`@2Dzz,
/** S81Z\=eK
* The constructor using fields +EK(r@eV
* 5{/CqUIl
* @param page mCOJ1}
* @param content uTgBnv(Y*
*/ _yk}
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public Result(Page page, List content){ M0VC-\W7f
this.page = page; HEdOo~/~
this.content = content; hp=TWt~
} =.NZ{G
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/** 9DcUx-
* @return Returns the content. 3yg22y&l
*/ t9T3e
publicList getContent(){ <{!^
return content; o8B_;4uB
} 7xz~%xC.
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/** #vh1QV!Ho
* @return Returns the page. 2c:H0O
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*/ Dlz||==
public Page getPage(){ :aHD'K
return page; 'D#iT}Vu
} eLE9-K+
DE"KbA0}
/** EXn$ [K;
* @param content Y8!T4dkn
* The content to set. L(tS]yWHw
*/ \|^fG9M~
public void setContent(List content){ %~%1Is`4J
this.content = content; y\0<f `v6
} w20E]4"
`.>5H\w0e
/** Fq3[/'M^
* @param page BkfWZ O{7
* The page to set. 18JhC*in
*/ 0_b7*\x c
publicvoid setPage(Page page){ 9Br2}!Ny
this.page = page; Cw;&{jY
} 8qwc]f$.w
} DCS$d1
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2. 编写业务逻辑接口,并实现它(UserManager, qT]Bl+h2
iw1((&^)"
UserManagerImpl) Yc;cf%c1
java代码: T{=.mW^ x
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/*Created on 2005-7-15*/ OdX-.FFl
package com.adt.service; h.0Y!'?
XvBEC_xWZ
import net.sf.hibernate.HibernateException; bm1+|gssn
cGSoAK
import org.flyware.util.page.Page; + wd} '4)
]:TX> X!
import com.adt.bo.Result; ),`MAevp
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/** L'=e /&
* @author Joa xTQV?g
J
*/ ,Ie~zZE&
publicinterface UserManager { *8k`m)h26
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public Result listUser(Page page)throws .N~qpynY
a(CZGIB
HibernateException; p'{ `Uvr
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} G3QB Rh{
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y@g{:/cmO
g;en_~g3j
K]dqK'
java代码: kfb+OE:7
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3}O.B
r|
/*Created on 2005-7-15*/ g3{)AX[Uy
package com.adt.service.impl; ;aYPv8s~,:
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import java.util.List; bu"Jb4_a>
N]cGJU>$
import net.sf.hibernate.HibernateException; =DTn9}u
gOw|s1`2,
import org.flyware.util.page.Page; ~D@pk>I
import org.flyware.util.page.PageUtil; )CS7>Vx
AEkgm^t.{
import com.adt.bo.Result; &*g5kh{
import com.adt.dao.UserDAO; U@[P.y~J
import com.adt.exception.ObjectNotFoundException; Y1AbG1n|
import com.adt.service.UserManager; qS{lay
,u QLXF2
/** *|AnL}GJ
* @author Joa 6Nx T W
*/ dtjaQsJM^
publicclass UserManagerImpl implements UserManager { xD#PM |I
lD2>`s5
private UserDAO userDAO; @Zd+XWFw
}4xxge?r
/** THQW8 V
* @param userDAO The userDAO to set. oMda)5 &
*/ g92M\5
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publicvoid setUserDAO(UserDAO userDAO){ wbI(o4rXE
this.userDAO = userDAO; &:L8; m
} {neE(0c
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/* (non-Javadoc) `g%]z@'+?
* @see com.adt.service.UserManager#listUser !$h%$se
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(org.flyware.util.page.Page) y5?T`ts,#
*/ Cq1t[a
public Result listUser(Page page)throws t&SJ!>7_c
uR)itmc?
HibernateException, ObjectNotFoundException { 'xZxX3
int totalRecords = userDAO.getUserCount(); Wf_aEW&n
if(totalRecords == 0) ,: w~-
throw new ObjectNotFoundException [K13Jy+
O89<IXk
("userNotExist"); g2C-)*'{yh
page = PageUtil.createPage(page, totalRecords); 9In&vF7$
List users = userDAO.getUserByPage(page); H_;Dq*
returnnew Result(page, users); ` 2|~Z
H
} hX)r%v:
=pWpHbB.
} fh$U"
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3]'=s>UO>^
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 SiojOH
#Vn=(U4}!_
询,接下来编写UserDAO的代码: 2bX!-h
3. UserDAO 和 UserDAOImpl: y=9a2[3Dz
java代码: %H<w.]>
bXq,iX
2 T{PIJg3
/*Created on 2005-7-15*/ \,
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package com.adt.dao; (#c5Q&