Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3 Z1OX]R
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 LN^UC$[tk
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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 9 mPIykAj8
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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 DbtF~`3, .
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分页支持类: $O9Xx
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java代码: ;'HF'Z
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package com.javaeye.common.util; 9!}q{2j
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import java.util.List; `(DJs-xD
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publicclass PaginationSupport { s4$X
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publicfinalstaticint PAGESIZE = 30; ^PqMi:htc
iCrxV{
privateint pageSize = PAGESIZE; #6W,6(#^#
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privateList items; O!^; mhy"
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privateint totalCount; p7C!G1+z
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privateint[] indexes = newint[0]; jK3\K/ob(
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privateint startIndex = 0; *vnXlV4L
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public PaginationSupport(List items, int [M:S`{SbY
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totalCount){ ?2ItB `<(
setPageSize(PAGESIZE); ArzDI{1
setTotalCount(totalCount); @B`Md3$7
setItems(items); P^[/Qi}j
setStartIndex(0); tg 85:
} Nfw YDY
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public PaginationSupport(List items, int mW4%2fD[
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totalCount, int startIndex){ q4ipumy*
setPageSize(PAGESIZE); =yqHC<8:
setTotalCount(totalCount); ;S JF%@x
setItems(items); vT7g<
setStartIndex(startIndex); _]|Qec)
} <9ifPSvJ
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public PaginationSupport(List items, int )X5(#E
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totalCount, int pageSize, int startIndex){ XP?*=Z]
setPageSize(pageSize); </s,pe79B
setTotalCount(totalCount); v <Hb-~
setItems(items); z[9UQU~x?
setStartIndex(startIndex); w`gyE
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} r,xmEj0E
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publicList getItems(){ jN/ j\x'
return items; =;{^"#r\
} r{[OJc!
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publicvoid setItems(List items){ qn"K9k
this.items = items; M{Gxjmdx
} (C S8(C4[
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publicint getPageSize(){ 3nFt1E
return pageSize; }1 QF+Cf
} )q3"t2-
v01#>,R
publicvoid setPageSize(int pageSize){ u7=T(4a
this.pageSize = pageSize; YaL]>.;Z:"
} k+1gQru{d
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publicint getTotalCount(){ B8V,)rn
return totalCount; {1~T]5
} usOx=^?=
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publicvoid setTotalCount(int totalCount){ &[j]Bp?
if(totalCount > 0){ *YvRNHP
this.totalCount = totalCount; pn\V+Rg'
int count = totalCount / n%$ &=-Fk
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pageSize; C6QbBo
if(totalCount % pageSize > 0) js <Ww$zFW
count++; ^Mytp> 7
indexes = newint[count]; FtIa*j^G
for(int i = 0; i < count; i++){ p2d\ZgWD=)
indexes = pageSize * '*R%^RK
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i; g`?:=G:a*
} X9XI;c;b-
}else{ QUOKThY?
this.totalCount = 0; sN/+
} l[%lE
} `# ^0cW
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publicint[] getIndexes(){ kso*} uh0
return indexes; {p/YCch,
} h6M;0_'
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publicvoid setIndexes(int[] indexes){ SY
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this.indexes = indexes; o""~jc~
} KCtX$XGL
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publicint getStartIndex(){ .\)A@ua^
return startIndex; U5+vN[ K
} h$fe -G#
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publicvoid setStartIndex(int startIndex){ j[e,?!8;
if(totalCount <= 0) ;BBpN`T
this.startIndex = 0; '^}+Fv<O
elseif(startIndex >= totalCount) yV]xRaRr2
this.startIndex = indexes R$6qoqv{yG
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[indexes.length - 1]; +nU.p/cK+\
elseif(startIndex < 0) u#jC#u^M
this.startIndex = 0; &u8z5pls8
else{ OJ,m1{9$}
this.startIndex = indexes E%3TP_B3
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[startIndex / pageSize]; rFu ez$
} -s"0/)HD
} Ijedo/
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publicint getNextIndex(){ j_Nm87i]
int nextIndex = getStartIndex() + n1J]p#nCa.
`X8@/wf#
pageSize; fRHKQ(a#
if(nextIndex >= totalCount) tXq)nfGe{
return getStartIndex(); ! OE*z $\
else IXq(jhm8bL
return nextIndex; l(:kfR~AC
} 2\@Z5m3B
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publicint getPreviousIndex(){ 6|=j+rScv
int previousIndex = getStartIndex() - ];FtS>\x
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pageSize; ijW7c+yd
if(previousIndex < 0) _\zQ"y|G
return0; PT_KXk
else ZGz|m0b (
return previousIndex; h;M3yTM-
} oU+F3b}5p
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} jk70u[\
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抽象业务类 s3
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java代码: 6STp>@Ch]"
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/** FFcB54ALTf
* Created on 2005-7-12 !I8f#'p
*/ .6.^G
package com.javaeye.common.business; P&=lV}f
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import java.io.Serializable; qqOFr!)g
import java.util.List; O)#U ^
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import org.hibernate.Criteria; $c9k*3{<+A
import org.hibernate.HibernateException; Tlsa%pn
import org.hibernate.Session; A
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import org.hibernate.criterion.DetachedCriteria; f)NHM'
import org.hibernate.criterion.Projections; K+d2m9C=
import jRj=Awy
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org.springframework.orm.hibernate3.HibernateCallback; !G?gsW0\h
import I.V:q!4*
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org.springframework.orm.hibernate3.support.HibernateDaoS aMwB>bt
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upport; H lB]38
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import com.javaeye.common.util.PaginationSupport; q,l)I+
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public abstract class AbstractManager extends sqO<J$tz
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HibernateDaoSupport { ?M}S|dsmE
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privateboolean cacheQueries = false; qx)?buAij
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privateString queryCacheRegion; 9F##F-%x
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publicvoid setCacheQueries(boolean U
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cacheQueries){ 6|;Uq'
this.cacheQueries = cacheQueries; }nrXxfu
} {aOkV::
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publicvoid setQueryCacheRegion(String eSy(~Y
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queryCacheRegion){ 5ukp^OxE
this.queryCacheRegion = "@ E3MTW
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queryCacheRegion; *yaw$oB
} ocQWQ
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publicvoid save(finalObject entity){ iEHh{H(
getHibernateTemplate().save(entity); f~h~5
} Y`ihi,s`H
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publicvoid persist(finalObject entity){ WZewPn>#q
getHibernateTemplate().save(entity); f`$Gz
} |+f-h,
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publicvoid update(finalObject entity){ VLvS$0(}Z
getHibernateTemplate().update(entity); x\\7G^$<h
} >lzA]aM$c
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publicvoid delete(finalObject entity){ tw K^I6@
getHibernateTemplate().delete(entity); ^twivNB
} u=NG6G
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publicObject load(finalClass entity, !{UTD+|=N
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finalSerializable id){ AHbZQulC
return getHibernateTemplate().load mOBACTY^
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(entity, id); Jfhk@27T
} v/QUjXBr
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publicObject get(finalClass entity, LJTo\^*
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finalSerializable id){ X_ TiqV
return getHibernateTemplate().get NC"yDWnO'
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(entity, id); QWO]`q`|
} w4};q%OBj
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publicList findAll(finalClass entity){ /bVZ::A&_
return getHibernateTemplate().find("from YZwaD b
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" + entity.getName()); /@oLe[Mz$
} /DFV$+9
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publicList findByNamedQuery(finalString ?UZ?NY
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namedQuery){ ZCui Fm
return getHibernateTemplate
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().findByNamedQuery(namedQuery); a:Q[gF8>
} Z|m`7xeCy
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publicList findByNamedQuery(finalString query, Wch~Yb
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finalObject parameter){ fw-\|fP
return getHibernateTemplate "MOpsb,
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().findByNamedQuery(query, parameter); Qu\@Y[eia5
} l?q qqB
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publicList findByNamedQuery(finalString query, hf<J
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finalObject[] parameters){ #2p#VQh
return getHibernateTemplate }F=^O[
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().findByNamedQuery(query, parameters); :7.Me;RA
} a:rX9-**
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publicList find(finalString query){ ^krk&rW3
return getHibernateTemplate().find t'qL[r%?
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(query); &%=D \YzG
} x_w~G]! /
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publicList find(finalString query, finalObject ja=w5
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parameter){ <,@%*G1-
return getHibernateTemplate().find YlK7;yrq(
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(query, parameter); FiAY\4
} n> w`26MMp
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public PaginationSupport findPageByCriteria )]6hy9<
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(final DetachedCriteria detachedCriteria){ :py\|
return findPageByCriteria P Ru&3BP
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); z}4L=KR\v
} ;/O#4]2*
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public PaginationSupport findPageByCriteria rxZi8w>}
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(final DetachedCriteria detachedCriteria, finalint R[[ ,q:4
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startIndex){ M!m?#xz'c
return findPageByCriteria j6:7AH|!)2
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(detachedCriteria, PaginationSupport.PAGESIZE, v({N:ya
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startIndex); P7 y q^|
} q3e8#R)l
}(FPV*mS
public PaginationSupport findPageByCriteria }M>rE
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(final DetachedCriteria detachedCriteria, finalint i\?*=\a
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pageSize, ,T{<vRj7_
finalint startIndex){ x34f9!
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return(PaginationSupport) %CnxjtTo
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getHibernateTemplate().execute(new HibernateCallback(){ @\P4/+"9
publicObject doInHibernate y*b3&%.ml
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(Session session)throws HibernateException { `{K_/Cit
Criteria criteria = oDB`iiBXQ
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detachedCriteria.getExecutableCriteria(session); Qt>>$3]!!
int totalCount = ?V(^YFzZ
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((Integer) criteria.setProjection(Projections.rowCount zU5Hb2a
u eb-2[=
()).uniqueResult()).intValue(); ;^){|9@
criteria.setProjection _wDS#t;!M
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(null); ,yMU@Vg
List items = +JyUe
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criteria.setFirstResult(startIndex).setMaxResults < B g8,;
;T +pu>)
(pageSize).list(); j+4H}XyE
PaginationSupport ps = H U+ I
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new PaginationSupport(items, totalCount, pageSize, 62'1X"
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startIndex); v}JD2.O+
return ps; cQj-+Tmu
} +/{L#e>
}, true); H1:be.^YP
} wNJzwC&iQ
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public List findAllByCriteria(final xG2F!WeF
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DetachedCriteria detachedCriteria){ t~7V{ xk
return(List) getHibernateTemplate z;\d L
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().execute(new HibernateCallback(){ w(d>HHg
publicObject doInHibernate L5YnG_M&
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(Session session)throws HibernateException { _Xcn
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Criteria criteria = `YBkF
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detachedCriteria.getExecutableCriteria(session); [V8fu
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return criteria.list(); M\<w#wZ
} E ]9\R
}, true); Lv[OUW#S
} 266oTER]v:
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public int getCountByCriteria(final E; $+f
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DetachedCriteria detachedCriteria){ AV8T
Integer count = (Integer) |Hr:S":9
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getHibernateTemplate().execute(new HibernateCallback(){ g| <wyt[
publicObject doInHibernate YGvUwj'2a
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(Session session)throws HibernateException { &;TJ~r#K
Criteria criteria = u6u=2
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detachedCriteria.getExecutableCriteria(session); MxQ?Sb%Gka
return [4&#*@
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criteria.setProjection(Projections.rowCount Os%n{_#8
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()).uniqueResult(); =DbY? Q<Q
} `/&SxQB<
}, true); Z;Rp+X
return count.intValue(); pv!oz2w1
} [%A4]QzWh
} ?(6m VyIe
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用户在web层构造查询条件detachedCriteria,和可选的 )jrT6x^IB
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 va|*c22;|
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PaginationSupport的实例ps。 ?']h%'Q
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ps.getItems()得到已分页好的结果集 P>Euq'ajX
ps.getIndexes()得到分页索引的数组 S"m cUU}}
ps.getTotalCount()得到总结果数 `fXyWrz-k
ps.getStartIndex()当前分页索引 %?C8mA'w
ps.getNextIndex()下一页索引 J<gJc*Q
ps.getPreviousIndex()上一页索引 h&3YGCl
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /Ss7"*JLe
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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 d'6|: z9c
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一下代码重构了。 5qUTMT['T
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我把原本我的做法也提供出来供大家讨论吧: |H}m 4-+*
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首先,为了实现分页查询,我封装了一个Page类: iTh:N2/-vc
java代码: [L$9p@I
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/*Created on 2005-4-14*/ ^&/G|
package org.flyware.util.page; jDM
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spofLu.
/** ]&~]#vB#
* @author Joa {4aWR><
*
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*/ BElJB&I
publicclass Page { Il@Y|hK
z\ss4
/** imply if the page has previous page */ q}BzyC=:n
privateboolean hasPrePage; gnp~OVDqfL
^[-el=oKn0
/** imply if the page has next page */ P|2E2=G
privateboolean hasNextPage; &M/0g]4p
OU4pjiLx
/** the number of every page */ HpEQEIvt
privateint everyPage; 7`IpBm<
yV3^Qtb!
/** the total page number */ ZD#9&q'4<
privateint totalPage; \AUI|M;'
Z}A%=Z\/3
/** the number of current page */ 0Z<I%<8bK
privateint currentPage; tj]9~eJ-
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/** the begin index of the records by the current Cd79 tu|
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query */ :4)Qt
privateint beginIndex; qjAWeS/
/N>e&e[35\
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/** The default constructor */ h0oMTiA
public Page(){ ]9=h%5Ji>
1
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} 8l?piig#
B<8N96fx
/** construct the page by everyPage I-]>d;4.
* @param everyPage *rZ^^`4R
* */ ^ 5VK>
public Page(int everyPage){ 3($"q]Y
this.everyPage = everyPage; 5m=I*.qE
} MC((M,3L
K'iIJA*Sn
/** The whole constructor */ b?4/#&z]
public Page(boolean hasPrePage, boolean hasNextPage, M}_i52
jJ4qR:]
g>d;|sK
int everyPage, int totalPage, HBys
int currentPage, int beginIndex){ ultG36.x
this.hasPrePage = hasPrePage; \7MHaQvS
this.hasNextPage = hasNextPage; GBFw+v/|4
this.everyPage = everyPage; &AuF]VT
this.totalPage = totalPage; 0U/K7sZ
this.currentPage = currentPage; c(co\A.]:6
this.beginIndex = beginIndex; 5F t5@UF~
} VN0mDh?E
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/** r!P}u
* @return 2>-S-;i
* Returns the beginIndex.
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*/ RO0>I8c1c
publicint getBeginIndex(){ 3Y)PU=
return beginIndex; S0g'r
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} aw?=hXR!
=z{JgD/
/** +5.t. d
* @param beginIndex ri C[lB
* The beginIndex to set. N4;7gSc"
*/ ]Mj/&b>"e
publicvoid setBeginIndex(int beginIndex){ Sp}D;7
this.beginIndex = beginIndex; bi ozZ
} ]J9cVp
133I.XBU
/** V Km!Ri$
* @return FVv8--
* Returns the currentPage. 4$/i%B#ad
*/ ~.PO[hC
publicint getCurrentPage(){ .0 u/|Yx
return currentPage; T,fI BD:
} Tj~IaU
S1 _6C:^k
/** qj01]
* @param currentPage H4OhIxK
* The currentPage to set. ky>wOaTmN6
*/ NVIK>cT6
publicvoid setCurrentPage(int currentPage){ o ]Jv;Iy@?
this.currentPage = currentPage; s{ V*1$e~
} r4x3$M c
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/** L.xZ_ 6
* @return xX0-]Y h:
* Returns the everyPage. Cp^@zw*/
*/ d"G+8}.4
publicint getEveryPage(){ (nW67YTr
return everyPage; h0?2j)X_
} jNwjK0?
/$n ~lf
/** e98lhu"|H
* @param everyPage V&soN:HS
* The everyPage to set. .%'(9E
*/ _qvK*nE
publicvoid setEveryPage(int everyPage){ VhT=
l
this.everyPage = everyPage; in<Rq"L
} j4FeSGa
oHM
]
/** *O:r7_ Y0
* @return :ztr)
* Returns the hasNextPage. h@7FY
*/ ?^'
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publicboolean getHasNextPage(){ I O%6 O
return hasNextPage; dAP|:&y@
} 2LCB])X
M)?dEgU}M
/** ~mV"i7VX
* @param hasNextPage OE)~yKy
* The hasNextPage to set. ?EMK8;
*/ bG&"9b_c
publicvoid setHasNextPage(boolean hasNextPage){ }14{2=!Q
this.hasNextPage = hasNextPage; $=sXAK9
} IUGz =%[
A>VI{
/** i$^)UZJ&0
* @return [=uo1%
* Returns the hasPrePage. DfJ2PX}q
*/ d#:3be{|&q
publicboolean getHasPrePage(){ %zC[KE*~
return hasPrePage; SgMrce<;
} HQ9f ,<
F Kc;W
/** E}CiQUx
* @param hasPrePage bLz*A-
* The hasPrePage to set. kH*P n'
*/ 3`hUo5K
publicvoid setHasPrePage(boolean hasPrePage){ >idBS
this.hasPrePage = hasPrePage; ezhDcI_T
} [MX;,%;;
|(
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/** [#" =yzR<3
* @return Returns the totalPage. *y`%]Hy<
* j^`X~gE
*/ /|{,sWf2
publicint getTotalPage(){ AJt!!crs
return totalPage; `\=Gp'&Q+
} r#WT`pav
4!$
M q;U
/** U]qav,^[
* @param totalPage PYB+FcR6?n
* The totalPage to set. 2^~<("+w
*/ (-7ZI"Ku
publicvoid setTotalPage(int totalPage){ R7oj#
this.totalPage = totalPage; %v5R#14[n
} jD){I
W]<$0
} K.tlo^#^B[
"Z,q?F c
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 @e~]t}fH
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个PageUtil,负责对Page对象进行构造: di9!lS$
java代码: Hx^!:kxk
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KH KS$D
/*Created on 2005-4-14*/ q^8EOAvnZ
package org.flyware.util.page; k1z$e*u&r
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import org.apache.commons.logging.Log; 0X..e$ '
import org.apache.commons.logging.LogFactory; oC*ees
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/** +5<k-0v
* @author Joa
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* CozKyt/r7
*/ P#kGX(G9!
publicclass PageUtil { D| I Ec?
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privatestaticfinal Log logger = LogFactory.getLog wbbqt0un
hRaf#
(PageUtil.class); 5FvOznK^e
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/** pvWau1ArNq
* Use the origin page to create a new page Hyk'c't_O
* @param page 5G}6;U Y
* @param totalRecords !.-tW7
* @return ?9j{V7h
*/
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publicstatic Page createPage(Page page, int h4&;?T S
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totalRecords){ v|Jlf$>
return createPage(page.getEveryPage(), hSqY$P
Rz%e>)
page.getCurrentPage(), totalRecords); @}F Awv^f
} )\/
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Ob +9W
/** a+41|)pt
* the basic page utils not including exception /%x7+Rl\-^
!&kL9A).
handler (Ha@s^?.C
* @param everyPage UyYfpL"$A"
* @param currentPage _cJ[
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* @param totalRecords 9~AWn g
* @return page ,a|@d}U
*/ hp!d/X=J_
publicstatic Page createPage(int everyPage, int iCG`3(xL
`ue[q!Qq
currentPage, int totalRecords){ ~d>%,?zz
everyPage = getEveryPage(everyPage); _fTwmnA
currentPage = getCurrentPage(currentPage); ";3*?/uM
int beginIndex = getBeginIndex(everyPage, `hh9"Ws%
XaI;2fMGI
currentPage); ;uI~BV*3
int totalPage = getTotalPage(everyPage, $Ptk|qFe
W+>wu%[L
totalRecords); BW[5o3
i
boolean hasNextPage = hasNextPage(currentPage, =y ]Jl,_.
i`U:gw
totalPage); cH`^D?#se
boolean hasPrePage = hasPrePage(currentPage); qV1O-^&[f=
O_@2;iD^^
returnnew Page(hasPrePage, hasNextPage, T(X:Yw
everyPage, totalPage, GrEs1M1]*
currentPage, IY(h~O
`{<frB@
beginIndex); *3{J#Q6fk3
} =fLL|
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privatestaticint getEveryPage(int everyPage){ _"f :`
return everyPage == 0 ? 10 : everyPage; 3*S[eqMJc
} Ng<1Sd|MV
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privatestaticint getCurrentPage(int currentPage){ $`Nd?\$
return currentPage == 0 ? 1 : currentPage; /F[+13C
} tn<6:@T
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privatestaticint getBeginIndex(int everyPage, int #Fd W/y5
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currentPage){ iSp
return(currentPage - 1) * everyPage; CDg AGy
} 60B-ay0e$b
rnhFqNT:
privatestaticint getTotalPage(int everyPage, int Bt~s*{3$8
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totalRecords){ :xeLt;
int totalPage = 0; IhonnLLW
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if(totalRecords % everyPage == 0) Z[#IfbYt
totalPage = totalRecords / everyPage; Ueyw;Y
else n[k1np$7?6
totalPage = totalRecords / everyPage + 1 ; ?T*";_o,B
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return totalPage; )q^ Bj$
} P;91~``b-
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privatestaticboolean hasPrePage(int currentPage){ B!,yfTk]
return currentPage == 1 ? false : true; is#8R:7.:
} vE\lp8j+
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privatestaticboolean hasNextPage(int currentPage, L'kq>1QWf
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int totalPage){ hY8#b)l~lu
return currentPage == totalPage || totalPage ==
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0 ? false : true; u}jrfKdE
} h8}8Lp(/'
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} E&2tBrAq
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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。 }=@zj6AC
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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 [%8@DC'
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做法如下: zXre~b03ZS
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 =HE
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的信息,和一个结果集List: {yq8<?
java代码: TbNGgjT
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/*Created on 2005-6-13*/ gue(C(~.k_
package com.adt.bo; Yo2Trh
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import java.util.List; ~775soN
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import org.flyware.util.page.Page; :R+],m il
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/** k&GHu0z
* @author Joa a!t
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*/ &'O?es|Lb
publicclass Result { nFXAF!,jj
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private Page page; YNM\pX'
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private List content; oh&Y<d0
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/** OV|Z=EwJ
* The default constructor yX9B97XyC
*/ *Mi6
public Result(){
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super(); ;BTJ%F.
} )73DT3-0$
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/** O,9X8$5H-a
* The constructor using fields >eo8
* jOl 1_
* @param page NgxO&Zp
* @param content RndOm.TE
*/ qJMp1DC
public Result(Page page, List content){ ` u=<c
this.page = page; h.b+r~u
this.content = content; >B~?dT m
} s1=u{ET
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/** Oxn'bh6R0
* @return Returns the content. 6D^%'[4t
*/ r}@< K
publicList getContent(){ ~7BX@?
return content; Qa?QbHc
} vs*I7<
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/** M9g1d7%
* @return Returns the page. AIfk"2
*/ w:R]!e_6\9
public Page getPage(){ V'yxqI?
return page; oZvG3_H4.
} B}5XRgq
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/** L&HzN{K
* @param content m?vAyi
* The content to set. ^V,@=QL3U
*/ q_58Lw
public void setContent(List content){ 3mA/Nu_
this.content = content; Ib(,P3
} !L$oAqW
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/** <w11nB)
* @param page ~$ WQ"~z
* The page to set. |
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*/ 1
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publicvoid setPage(Page page){ _^3@PM>
this.page = page; KqY>4tb
} |Kn^w4mN
} Z{16S=0
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2. 编写业务逻辑接口,并实现它(UserManager, /K&