Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 'iO?M'0gE#
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 \^iPU 27H
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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 E
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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 !oeu
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分页支持类: ;crQ7}k
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java代码: ig:/60Z
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package com.javaeye.common.util; 5EDN 9?a
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import java.util.List; \1'3--n
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publicclass PaginationSupport { 3*$A;%q
@'U9*:}U
publicfinalstaticint PAGESIZE = 30; *)k}@tY
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privateint pageSize = PAGESIZE; `_sc_Y|C!
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privateList items; Tl=cniy]
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privateint totalCount; !%x8!;za
) W)m?%
privateint[] indexes = newint[0]; UKp- *YukT
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privateint startIndex = 0; knX0b$$
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public PaginationSupport(List items, int pv&:N,p
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totalCount){ yiGq?WA7
setPageSize(PAGESIZE); 9ctvy?53H
setTotalCount(totalCount); `;b@a<Wl
setItems(items); Ed ,`1+
setStartIndex(0); O{a<f7 W
} ep .AW'+
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public PaginationSupport(List items, int mh]'/C_*<w
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totalCount, int startIndex){ )%x oN<
setPageSize(PAGESIZE); 6 ]W!>jDc
setTotalCount(totalCount); #+HLb
setItems(items); EZaWEW
setStartIndex(startIndex); <y=VDb/
} I&]d6,
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public PaginationSupport(List items, int A,i.1U"w8
*"` dO9Yf_
totalCount, int pageSize, int startIndex){ D_
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setPageSize(pageSize); ,~8:^*0s
setTotalCount(totalCount); >k,|N4(
setItems(items); /
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setStartIndex(startIndex); 90> (`pI=
} \#.,@g
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publicList getItems(){ Jm$.$B&I
return items; ~4h<nc
} lY/{X]T.(
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publicvoid setItems(List items){ HQ~`ha.
this.items = items; %0C<_drW
} OQMkpX-dH
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publicint getPageSize(){ CY#|VE M
return pageSize; JP`$A
} 6nh!g
<+ UEM~)
publicvoid setPageSize(int pageSize){ 73B,I 0U
this.pageSize = pageSize; j78WPG
} Pe6}y
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publicint getTotalCount(){ .?R~!K{`
return totalCount; 2g~qVT,
} Qd;P?W6
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publicvoid setTotalCount(int totalCount){ VZo[\sWf
if(totalCount > 0){ 1BT]_ cP
this.totalCount = totalCount; koOkm:(,
int count = totalCount / {Q],rv|;
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pageSize; C(zgBk
if(totalCount % pageSize > 0) |f), dC
count++; |U{9Yy6p
indexes = newint[count]; F: %-x=q
for(int i = 0; i < count; i++){ l?pF?({
indexes = pageSize * lM1~K
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i; TI4#A E
} ,5oe8\uz
}else{
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this.totalCount = 0; {$D[l
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} P^V,"B8t
} HS> (y2}'
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publicint[] getIndexes(){ >qj.!npQD
return indexes; K~'!JP8@
} x|4m*>Ke
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publicvoid setIndexes(int[] indexes){
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this.indexes = indexes; MU6|>{
} X`i'U7%I
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publicint getStartIndex(){ iUSP+iC,
return startIndex; *69{#qN
} -e<d//>
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publicvoid setStartIndex(int startIndex){ aT}Mn(F*?
if(totalCount <= 0) ?;84 M@
this.startIndex = 0; D4,kGU@
elseif(startIndex >= totalCount) ;1qE:x}'H
this.startIndex = indexes 8B#;ffkmN
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[indexes.length - 1]; O~
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elseif(startIndex < 0) j>jZg<}J
this.startIndex = 0; J{>9ctN
else{ )9/.K'o,dy
this.startIndex = indexes A!EmJ
j"(o>bv7
[startIndex / pageSize]; "Tw4'AY'P
} EmrUzaGD
} od~^''/b
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publicint getNextIndex(){ 1Q_ C
int nextIndex = getStartIndex() + \H<gKZquR
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pageSize; @z
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if(nextIndex >= totalCount) -& Qm"-?:
return getStartIndex(); oh*Hzb
else #yNSQd
return nextIndex; +*u'vt?
} [5[}2B_t
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publicint getPreviousIndex(){ Zop3[-
int previousIndex = getStartIndex() - $ti*I;)h4
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pageSize; 6P,vGmR
if(previousIndex < 0) =BD} +(3
return0; %=p:\+`VI
else s
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return previousIndex; Y~I$goT
} GMk\
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} TUE*mDRmP
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抽象业务类 R Lnsy,
java代码: "53'FRj_\
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/** -NzO ,?
* Created on 2005-7-12 DlC\sm
*/ _N`'R.va
package com.javaeye.common.business; WP(+jL^-
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import java.io.Serializable; 'u9,L FO
import java.util.List; 8H2zMIB
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import org.hibernate.Criteria; [tN^)c`s/
import org.hibernate.HibernateException; 0*e)_l!
import org.hibernate.Session; oJ\)-qSf
import org.hibernate.criterion.DetachedCriteria; (CUrFZT$
import org.hibernate.criterion.Projections; 1Yr&E_5/
import N5W;Zx]
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org.springframework.orm.hibernate3.HibernateCallback; NO$n-<ag
import |E{tS,{OhJ
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org.springframework.orm.hibernate3.support.HibernateDaoS FEOr'H<3x
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upport; +SM&_b
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import com.javaeye.common.util.PaginationSupport; w$5~'Cbi
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public abstract class AbstractManager extends ]V*ku%L0
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HibernateDaoSupport { 0^%\! Xxq
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privateboolean cacheQueries = false; A%Ov.~&\G
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privateString queryCacheRegion; r'TxYM-R
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publicvoid setCacheQueries(boolean :eK(9o
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cacheQueries){ )7X+T'?%
this.cacheQueries = cacheQueries; B: '}SA{
} 6CQ.>M:R
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publicvoid setQueryCacheRegion(String "o| f
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queryCacheRegion){ |6qxRWT"
this.queryCacheRegion = I
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queryCacheRegion; v~l_6V}
} 7z.(pg=
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publicvoid save(finalObject entity){ }"$2F0
getHibernateTemplate().save(entity); A~2U9f+\
} t>f61<27eB
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publicvoid persist(finalObject entity){ g&79?h4UXQ
getHibernateTemplate().save(entity); t h!$R
} bHJKX>@{
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publicvoid update(finalObject entity){ Lg;b17
getHibernateTemplate().update(entity); YN=dLr([<
} SHoov
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publicvoid delete(finalObject entity){ jb~W(8cj
getHibernateTemplate().delete(entity); ym\AVRO{
} E1|> O
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publicObject load(finalClass entity, T9s$IS ,
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finalSerializable id){ d65fkz==A)
return getHibernateTemplate().load S_Tv Ix/7&
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(entity, id); rP5&&Hso
}
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publicObject get(finalClass entity, {S9't;%]
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finalSerializable id){ P^lzl:|
return getHibernateTemplate().get /mi9q
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(entity, id); r>>4)<C7J
} U~;Rzoe)q*
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;
publicList findAll(finalClass entity){ eT(/D/jan
return getHibernateTemplate().find("from yN'<iTh
`[OJ)tHE
" + entity.getName()); cWNZ +Q8Y
} ]JQ+*ZYUE
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publicList findByNamedQuery(finalString T(GEFntY
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namedQuery){ .=~-sj@k
return getHibernateTemplate qD/GYqvm
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().findByNamedQuery(namedQuery); G}2DZ=&>'
} \n&l
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publicList findByNamedQuery(finalString query, P#8+GN+bF
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finalObject parameter){ 4R c_C0O
return getHibernateTemplate 3?}\Hw
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().findByNamedQuery(query, parameter); v$WH#;(\
} 8\AyKw
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publicList findByNamedQuery(finalString query, YK=o[nPmK
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finalObject[] parameters){ C >@T+xOZ
return getHibernateTemplate ak SUk)}e
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().findByNamedQuery(query, parameters); \zdY$3z
} _`oP*g =
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publicList find(finalString query){ k=nN#SMn
return getHibernateTemplate().find *y}<7R
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(query); =do*(
} lc:dKGF6
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publicList find(finalString query, finalObject 5W Z9z-6
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parameter){ ms(Z1ix^
return getHibernateTemplate().find o4[
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(query, parameter); h/LlH9S:!
} ^(Y}j8sj
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public PaginationSupport findPageByCriteria Dc1tND$X3g
2cB){.E
(final DetachedCriteria detachedCriteria){ <n+]\a97*
return findPageByCriteria x5X;^.1Fr
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); V[Z^Z
} !vrduOB
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public PaginationSupport findPageByCriteria |}FK;@'I 6
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(final DetachedCriteria detachedCriteria, finalint lI)RaiMr=
pv}k=wqJ1
startIndex){ b|rMmx8vA
return findPageByCriteria dj;Zzt3
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(detachedCriteria, PaginationSupport.PAGESIZE, 3iKy>
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startIndex); +,g"8&>
} ^xNs^wC.
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public PaginationSupport findPageByCriteria *GGiSt
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(final DetachedCriteria detachedCriteria, finalint ?*nFz0cs^
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pageSize, cn3F3@_"\
finalint startIndex){ =*[98%b
return(PaginationSupport) &|'t>-de,
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getHibernateTemplate().execute(new HibernateCallback(){ q!qOy/}D
publicObject doInHibernate Ir,3' G
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(Session session)throws HibernateException { @[2Go}VF
Criteria criteria = b3vPGR
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detachedCriteria.getExecutableCriteria(session); )-u0n],
int totalCount = `pTCK9
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((Integer) criteria.setProjection(Projections.rowCount iC.k8r+~
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()).uniqueResult()).intValue(); d%EUr9~?
criteria.setProjection {,9^k'9
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(null); y-1!@|l0:6
List items = J^Mq4&
v90)G8|q
criteria.setFirstResult(startIndex).setMaxResults C&1()U
}JWLm.e
(pageSize).list(); %x]8^vze
PaginationSupport ps = h{5K9$9=
h,!#YG@>
new PaginationSupport(items, totalCount, pageSize, f6*6 *=
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startIndex); -aV!ZODt
return ps; A><q-`bw
} l$\OSG
}, true); P{gGvC,
} sN_c4"\q
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public List findAllByCriteria(final jMAZ4M
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DetachedCriteria detachedCriteria){ ?nwFc3qw
return(List) getHibernateTemplate [#3*R_#8R
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().execute(new HibernateCallback(){ \I[f@D-J
publicObject doInHibernate Osk'zFiL<
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(Session session)throws HibernateException { g2|qGfl{C
Criteria criteria = m) -DrbE
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detachedCriteria.getExecutableCriteria(session); Pc:5*H
return criteria.list(); ,SQ`, C
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} ->rr4xaK C
}, true); 3$yOv"`
} 5dNM:1VoE
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public int getCountByCriteria(final -yJ%G1R
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DetachedCriteria detachedCriteria){ +!F+mV9
Integer count = (Integer) p7{%0
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getHibernateTemplate().execute(new HibernateCallback(){ v"I#.{LiH=
publicObject doInHibernate |}07tUq
{}A1[Y|
(Session session)throws HibernateException { 'Y;M%
Criteria criteria = @,i_Gw)
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detachedCriteria.getExecutableCriteria(session); A{IJ](5.kd
return +bhR[V{0g
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criteria.setProjection(Projections.rowCount oj'a%mx
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()).uniqueResult(); (=eJceE!
} oWP3Y.
}, true); t)__J\xF
return count.intValue(); =uil3:,[S
} 0hB9D{`,{
} [(kC/W)!
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用户在web层构造查询条件detachedCriteria,和可选的 ">|G^@|:A
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 H~ `JAplr
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PaginationSupport的实例ps。 +f"q^R IU
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ps.getItems()得到已分页好的结果集 ZdsYIRU#
ps.getIndexes()得到分页索引的数组 @GyxOc@6
ps.getTotalCount()得到总结果数 ~^ <1k-
ps.getStartIndex()当前分页索引 +!JTEKHKH
ps.getNextIndex()下一页索引 (l_/ HQ32
ps.getPreviousIndex()上一页索引 [zsUboCkc
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 l6~wm1vO
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 C>=[fAr mO
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一下代码重构了。 E},^,65
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我把原本我的做法也提供出来供大家讨论吧: 3I.0jA#T&/
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首先,为了实现分页查询,我封装了一个Page类: 'L5ih|$>
java代码: *I<L1g%9d
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/*Created on 2005-4-14*/ ?qt .+2:
package org.flyware.util.page; {^V9?^?d (
VNT*@^O_=
/** vAt]N)R
* @author Joa 'Z}3XVZEN
* QJ^'Uyfdn
*/ my+2@ln
publicclass Page { O]cuJp
{Q~HMe`,
/** imply if the page has previous page */ c_ Dg0
privateboolean hasPrePage; bD:[r))#e
$GJuS^@%
/** imply if the page has next page */ &$NYZ3?9
privateboolean hasNextPage; 1@<PcQBp
s%/x3anz=
/** the number of every page */ L}Rsg'U
privateint everyPage; {Lg]chJq?
;%a
/** the total page number */
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privateint totalPage; kD\7wz,ui
=~P)7D6
/** the number of current page */ rInZd`\
privateint currentPage; VtYrU>q
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/** the begin index of the records by the current 0U&@;/?
EC`=nGF
query */ -PiakX
privateint beginIndex; Q`)iy/1M
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/** The default constructor */ ]rS:#LK
public Page(){ WvN{f*
$,
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} e.Gjp{
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/** construct the page by everyPage 12o6KVV^x
* @param everyPage ?8-ho0f0
* */ (b#4Z
public Page(int everyPage){ ?8!\V NC.
this.everyPage = everyPage; &[W53Lqa
} E@/*eJ
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/** The whole constructor */ 8s9ZY4_
public Page(boolean hasPrePage, boolean hasNextPage, 'B9q&k%<
nw,XA0M3
P<C=9@`!
int everyPage, int totalPage, zFm:=,9
int currentPage, int beginIndex){ " 7g\X$
this.hasPrePage = hasPrePage; `6RR/~kP(
this.hasNextPage = hasNextPage; M97MIku~9
this.everyPage = everyPage; vX}#wDNP
this.totalPage = totalPage; <^(>o
this.currentPage = currentPage; T8NDS7&?
this.beginIndex = beginIndex; :-tMH02c
} +[2ep"5H
3,^.
/** ngOGo =
* @return l}_6_g>6
* Returns the beginIndex. oxNQNJ!X
*/ ,lDOo+eE%:
publicint getBeginIndex(){ &2sfu0K
return beginIndex; ^E&WgXlb
} !6FO[^h||H
[79iC$8B|
/** ;iO5
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* @param beginIndex k*K.ZS688
* The beginIndex to set. uJSzz:\
*/ e]*@|e4b
publicvoid setBeginIndex(int beginIndex){ UW'@3#<?
this.beginIndex = beginIndex;
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} trz&]v=:
|a!]Iqz"N
/** @kW RI* m
* @return iI Dun Ih
* Returns the currentPage. ,FL*Z9wA
*/ 3YD.Fjz$
publicint getCurrentPage(){ xQDWnpFc
return currentPage; #<DS-^W!
} W|(U}PrC
jidRh}>a=
/** ![&9\aH
* @param currentPage ^l{q{O7U$
* The currentPage to set. F% z$^ m-
*/ ~cul;bb#
publicvoid setCurrentPage(int currentPage){ VQ8Q=!]
this.currentPage = currentPage; 4 u=v
} 2= zw!
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/** gX]ewbPDQ
* @return Gz:ell$
* Returns the everyPage. Slv91c&md,
*/ gMs B1|
publicint getEveryPage(){ Z '~Ie~
return everyPage; H>F j
} bD`h/jYv
#z =$*\u
/** ]cM,m2^2
* @param everyPage r2m&z%N&
* The everyPage to set. \k3EFSm
*/ 6t4Khiwx
publicvoid setEveryPage(int everyPage){ nL+y"O
this.everyPage = everyPage; 6z2%/P-'
} g\1|<jb3
.u:aX$t+
/** :6J&%n
* @return R(f6uO!m
* Returns the hasNextPage. @?*;
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*/ ^$s&bH'8
publicboolean getHasNextPage(){ y I} >
return hasNextPage; kD}vK+
} RT<HiVr`
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/** L&0aS:
* @param hasNextPage 5c$\DZ(
* The hasNextPage to set. `_SV1|=="8
*/ Z8`Y}#Za [
publicvoid setHasNextPage(boolean hasNextPage){ uM,R +)3
this.hasNextPage = hasNextPage; .Bojb~zt
} 1 %8JMq\
3F32 /_`
/** OMAvJzK .
* @return $r)NL
* Returns the hasPrePage. n(W&GSj|u9
*/ [l}H%S
publicboolean getHasPrePage(){ x/0loW?q^
return hasPrePage; t==\D?Rt
} m(`O>zS
=w/AJ%6
/** 3_"tds <L
* @param hasPrePage o,RiAtdk
* The hasPrePage to set. w+$~ds
*/ 4UHviuOo8
publicvoid setHasPrePage(boolean hasPrePage){ B.:1fT7lI
this.hasPrePage = hasPrePage; z9E*1B+
} <R?S
u.Tknw-X
/** s8dP=_ `
* @return Returns the totalPage. Z1_F)5pn
* :eIQF7-
*/ {DZ xK(
publicint getTotalPage(){ P !I Lji!
return totalPage; Q/0oe())
} ]QGo(+
\1hQ7:f;\
/** g3
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* @param totalPage ={;7WB$
* The totalPage to set. mpQu:i|W
*/ =1y~Qlu
publicvoid setTotalPage(int totalPage){ kH`?^^_yJ
this.totalPage = totalPage; Pn l}<i
} x[xRqC
vL
aYM~Ub:x{
} )iid9K<HB
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@9~x@[
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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 frc9
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个PageUtil,负责对Page对象进行构造: z[@i=avPG
java代码: m\70&%v
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/*Created on 2005-4-14*/ Z5
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package org.flyware.util.page; lOM8%{.'_x
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import org.apache.commons.logging.Log; .osG"cS
import org.apache.commons.logging.LogFactory; qWf[X'
USaa#s4'
/** tu(^D23
* @author Joa \01 kK)
* ?Qx4Z3n
*/ w OOu/Y
publicclass PageUtil { P-<1vfThH
n(|rs
privatestaticfinal Log logger = LogFactory.getLog Ow(aRWUZD_
=zu;npM
(PageUtil.class); `"hWbmQ
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/** 5 D=r7
* Use the origin page to create a new page -9;?k{{[T
* @param page ?J-\}X
* @param totalRecords yL),G*[p\}
* @return >TiEYMW
*/ /8!n7a7
publicstatic Page createPage(Page page, int /;{L~f=et)
jT!?lqr(Rb
totalRecords){ %hlgLM
return createPage(page.getEveryPage(), sVGQSJJ5
yFS{8yrRUU
page.getCurrentPage(), totalRecords); RR'sW@
} #c":y5:
v+}${h9
/** eoXbZ
* the basic page utils not including exception Bl^BtE?-b
>; tE.CJH
handler yPY{ZADkQ
* @param everyPage g*`xEb='
* @param currentPage Q*M(d\V s
* @param totalRecords f:y1eLl3
* @return page Ke=+D'=
*/ R$66F>Jz^
publicstatic Page createPage(int everyPage, int xR8.1T?8
c{ +bY.J
currentPage, int totalRecords){ 8vtembna4
everyPage = getEveryPage(everyPage); ,LP^v'[V7
currentPage = getCurrentPage(currentPage); \Rb:t}
int beginIndex = getBeginIndex(everyPage, ^do6?e`?-
>#'?}@FWQN
currentPage); UvM4-M%2JN
int totalPage = getTotalPage(everyPage, \WbQS#Z9
DycXJ3eQ
totalRecords); HVhP |+
boolean hasNextPage = hasNextPage(currentPage, ?>iUz.];t
/h{Rf,H
totalPage); wOCAGEg
boolean hasPrePage = hasPrePage(currentPage); gFrNk
Uqp
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returnnew Page(hasPrePage, hasNextPage, }/h&`0z`
everyPage, totalPage, t72rCq QC
currentPage, KU*aJl_n,
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beginIndex); 13w(Tf
} 4T;<`{]
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privatestaticint getEveryPage(int everyPage){ H5 &._
return everyPage == 0 ? 10 : everyPage; co1aG,>"q
} rZcSG(d`53
tbiM>qxB
privatestaticint getCurrentPage(int currentPage){ mQR9Pn}H
return currentPage == 0 ? 1 : currentPage; D6|-nl
} 0xO*8aKT
^sFO[cYo
privatestaticint getBeginIndex(int everyPage, int /nu z_y\J
,hT.Ok={36
currentPage){ k`A39ln7wu
return(currentPage - 1) * everyPage; -%gEND-AP
} eO(U):C2
hqlQ-aytS
privatestaticint getTotalPage(int everyPage, int A0U9,M
Pr(@&:v:
totalRecords){ \G7F/$g
int totalPage = 0; %?aq1 =B
H0sTL#/L \
if(totalRecords % everyPage == 0) B f]Bi~w<
totalPage = totalRecords / everyPage; 9jX_Eoxy
else >KvK'Mus/
totalPage = totalRecords / everyPage + 1 ; y22DBB8
W3d+t?28
return totalPage; %''L7o.#a
} JAP(J~
g>;@(:e^/
privatestaticboolean hasPrePage(int currentPage){ |2@*?o"ll
return currentPage == 1 ? false : true; ; :q
} <Z<meB[g
a'/i/@h
privatestaticboolean hasNextPage(int currentPage, u%+k\/Scp.
hjM?D`5x
int totalPage){ Hh*?[-&r~
return currentPage == totalPage || totalPage == xE]y*\
yz=X{p1
0 ? false : true; \q4r/SbgW
} 1JfZstT
0Ci/-3HV!
{>9ED.t
} |3yG
#0Y_!'j
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qIQRl1Tw;V
h~](9 es
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。 Rz|@BxB>n
{\%I;2X
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 XD|g G
x: _[R{B
做法如下: |*UB/8C^/!
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 u4w!SD
z\A
),;
的信息,和一个结果集List: S#v3%)R
java代码: uf9&o#
QDV+(
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/*Created on 2005-6-13*/ 9A} *
package com.adt.bo; #Xox2{~
FE&:?
import java.util.List; F;8Q`$n
&JqaIJh
import org.flyware.util.page.Page; ,xVAJ6_#
{vCtp
/** 1^X)vck
* @author Joa ;l0dx$w
*/ -X~|jF
publicclass Result { t4G$#~
_`&l46
private Page page; ByJPSucD
0V(}Zj>
private List content; Zx_^P:rL
"O<ETHd0
/** 2~?E'
* The default constructor PWiUW{7z
*/ Cp"7R&s
public Result(){ z|D*ymz*EY
super(); U4\v~n\
} J;8d-R5
nWY^?e'S
/** 7<;oz30G!L
* The constructor using fields (BeJ,K7
* 6`@J=Q?
* @param page #o4tG
* @param content -dBWpT
*/ ]kTxVe
public Result(Page page, List content){ 3dj|jw5
this.page = page; v/c]=/
this.content = content; A8*zB=C
} U].]K
~Ss,he]Er
/** ][v]Nk
* @return Returns the content. LrbD%2U$j5
*/ A8Q^y
AP^
publicList getContent(){ {#k[-\|;
return content; CL4N/[UM
} 7\,9Gcv1
bC1G5`v_D
/** !LwHKCj
* @return Returns the page. ~Q]5g7k=&
*/ ,Q7;(&x~
public Page getPage(){ ?V^7`3F
return page; qz>R"pj0g
} GgG#]a!_f
pcwYgq#5
/** ud$-A
* @param content E6 -*2U)k+
* The content to set. M
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*/ /z*Z+OT2
public void setContent(List content){ O.( 2
this.content = content; +K`A2&F9
} ~s'tr&+
kt978qfk
/** @
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* @param page ngl +`|u
* The page to set. d9M[]{
*/ c:Nm!+5_(
publicvoid setPage(Page page){ 8$
u"92
this.page = page; h7UNmwj
} ~EPVu
} x~!|F5JbM
%ERcFI]G
;: 2U}p^-
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j/*1zu8Y
2. 编写业务逻辑接口,并实现它(UserManager, *b.
>
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UserManagerImpl) P U/<7P*
java代码: 96(Mu% l
\H@1VgmR;
|2u=3#Jp
/*Created on 2005-7-15*/ ?!U[~Gq
package com.adt.service; @I`^\oJ
hDW!pnj1
import net.sf.hibernate.HibernateException; |j`73@6
c
Rq2 re
import org.flyware.util.page.Page; VIP7j(#t_g
=\WF +r]V
import com.adt.bo.Result; r@{TN6U
!ka* rd
/** !B}9gT
* @author Joa 7t:RQ`$:
*/ yQD>7%x
publicinterface UserManager { SXm%X(JU
RDp
public Result listUser(Page page)throws (O5Yd 6u
*{DTxEy
HibernateException; W8^m-B&
zl|z4j'Irc
} yijP
Y"GNJtsL "
a4__1N^Qj
&xQM!f
3c=kYcj
java代码: 00QJ596
KkA)p/
t~->&Ja
/*Created on 2005-7-15*/ LKu\M h|
package com.adt.service.impl; S%i^`_=Q
ZNX38<3h
import java.util.List; l4oyF|oJTH
U%nkPIFm
import net.sf.hibernate.HibernateException; l}))vf=i
,RV
qYh(-|
import org.flyware.util.page.Page; YB5"i9T2
import org.flyware.util.page.PageUtil; Cku"vVw,
-)`_w^Ox
import com.adt.bo.Result; ixdsz\<
import com.adt.dao.UserDAO; 0Ds3wNz
import com.adt.exception.ObjectNotFoundException; 20;9XJmjl
import com.adt.service.UserManager; `r`8N6NQ&]
:}lqu24K
/** X g6ezlW
* @author Joa FPDTw8" B;
*/ CI'RuR3y]Z
publicclass UserManagerImpl implements UserManager { iAwEnQ3h
^a4z*#IOr
private UserDAO userDAO; x;n3 Zr;(
F)LbH&Kn
/** 5`QcPDp{z
* @param userDAO The userDAO to set. t;e&[eg
*/ M6)
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publicvoid setUserDAO(UserDAO userDAO){ lM6pYYEq=
this.userDAO = userDAO; hy5[
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} 5I622d
s<9g3Gh
/* (non-Javadoc) 6l]X{ A.
* @see com.adt.service.UserManager#listUser A9$x8x*Lt
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(org.flyware.util.page.Page) |1U_5w
*/ *2G6Q
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public Result listUser(Page page)throws % =^/^[D
NBYJ'nA%;f
HibernateException, ObjectNotFoundException {
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int totalRecords = userDAO.getUserCount(); =*2,^j
if(totalRecords == 0)
;A*SuFbV
throw new ObjectNotFoundException *;Jb=
9zu;OK%
("userNotExist"); )/T[Cnx.Nc
page = PageUtil.createPage(page, totalRecords); 2%W;#oi?
List users = userDAO.getUserByPage(page); H3A$YkK [
returnnew Result(page, users); 2r,
c{Ah@D
} 1qRquY
qb>41j9_t
} *NmY]
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Y2u\~.;oq
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m8q4t,<J
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 u^"
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4ax{Chn
询,接下来编写UserDAO的代码: u "[f\l
3. UserDAO 和 UserDAOImpl: <^5!]8*O
java代码: z5E%*]
yqT !A
uU H4vUa
/*Created on 2005-7-15*/ DXs an
package com.adt.dao; ar3L|MN
NAGM3{\5v$
import java.util.List; p5G'})x
!}(B=-
import org.flyware.util.page.Page; f9.?+.^_
ON :t"z5
import net.sf.hibernate.HibernateException; @!sK@&ow@%
17LhgZs&
/** uzYB`H<
* @author Joa 5'AP:3Gf"
*/ OW7
publicinterface UserDAO extends BaseDAO { Qs6<(zaqkt
3:)z+#Uk6
publicList getUserByName(String name)throws d>QFmsh-
WR;1
HibernateException; OM86C
1-2hh)
publicint getUserCount()throws HibernateException; l A ^1}
Br1R++]
publicList getUserByPage(Page page)throws %B s. XW,
J=g)rd[`
HibernateException; a=z] tTs4
ci0A!wWD
} "#Rh\DQ
;tOsA #
c_J9CKqc
@\K[WqF$$q
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java代码: dWAt#xII
d$t"Vp
MmF&jd-=
/*Created on 2005-7-15*/ JJ: ku&Mb
package com.adt.dao.impl; YQBLbtn6(
1"h"(dA
import java.util.List; {,>G 1>Yv
R9J!}az'
import org.flyware.util.page.Page; 'VDWJTia
=sJ?]U
import net.sf.hibernate.HibernateException; d"wA"*8~y
import net.sf.hibernate.Query; ?nU<cx h
]aX@(3G1s
import com.adt.dao.UserDAO; o) )` "^
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/** K~W(ZmB
* @author Joa 9YzV48su#
*/ K-RmB4WI
public class UserDAOImpl extends BaseDAOHibernateImpl )Z7Vm2a
;mQj2Bwr
implements UserDAO { ?cU,%<r
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/* (non-Javadoc) NL21se
* @see com.adt.dao.UserDAO#getUserByName q lc@$
a4Q@sn;]
(java.lang.String) /%@;t@BK4
*/ 6v`3/o
publicList getUserByName(String name)throws 9+ 'i(q
z
fdl.3~.C
HibernateException { T{dQ4
c
String querySentence = "FROM user in class e~)[I! n
JT+c7W7
com.adt.po.User WHERE user.name=:name"; YWZ;@,W
Query query = getSession().createQuery +%dXB&9x|Z
U]PB)
(querySentence); SNj-h>&Mha
query.setParameter("name", name); fO<40!%9cQ
return query.list(); j.E=WLKV*
} zv]ZEWVzc
1lw%RM
/* (non-Javadoc) 8Qv s\TY
* @see com.adt.dao.UserDAO#getUserCount() -Vn#Ab_C
*/ O(^h_
publicint getUserCount()throws HibernateException { -FZC|[is
int count = 0; C- .;m
String querySentence = "SELECT count(*) FROM +O}Ik.w
C`5'5/-.
user in class com.adt.po.User"; ]!/
Query query = getSession().createQuery #p}GWS)
(< +A w7
(querySentence); |UTajEL
count = ((Integer)query.iterate().next ;(C<gt,r}
#U:|-
a.>
()).intValue(); oE 'P
return count; IuwE&#
} adLL7
4'QX1p
/* (non-Javadoc) -S$F\%
* @see com.adt.dao.UserDAO#getUserByPage U5Hi9fe
"*d6E}wG
(org.flyware.util.page.Page) &8$v~
*/ )qy?x7
publicList getUserByPage(Page page)throws gk6f_0?X'
~I||"$R
HibernateException { ifDWN*k6
String querySentence = "FROM user in class 1 Pk+zBJ$
PaCCUF
com.adt.po.User"; |ADf~-AY
Query query = getSession().createQuery g p:0 Y
}3
xkA
(querySentence); P:{Aqn~zR
query.setFirstResult(page.getBeginIndex()) eHr0],
.setMaxResults(page.getEveryPage()); VYG@_fd!x
return query.list(); A
\/~u"Y
} `~XksyT
jQ{ @ol}n
} Xm#W}Y'
UoxlEec
v>8.TE~2
En\@d@j<u
e,%|sAs[
至此,一个完整的分页程序完成。前台的只需要调用 _dKMBcl)E
UarLxPQ
userManager.listUser(page)即可得到一个Page对象和结果集对象 | 6{JINW
9pLe8D
的综合体,而传入的参数page对象则可以由前台传入,如果用
p9"dm{
JSL&`
`
webwork,甚至可以直接在配置文件中指定。 $;^|]/-
5*44QV
下面给出一个webwork调用示例: u@Hz7Q}
P
java代码: ?UsCSJ1V
0YiTv;mq;
Mt.Cj;h@^[
/*Created on 2005-6-17*/ _r:Fmn_%-
package com.adt.action.user; )+N{D=YM
\,13mB6
import java.util.List; MT!Y!*-5
uWJJ\
import org.apache.commons.logging.Log; J4+K)gWB
import org.apache.commons.logging.LogFactory; "^&H9