Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 z7{b>oub('
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 7Y@&&
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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 qN+ ngk,:
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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 ]_|qv1K6
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分页支持类: uGc}^a2
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java代码: t1g)Y|@d
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package com.javaeye.common.util; @(Ou;Uy
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import java.util.List; "-A@>*g
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publicclass PaginationSupport { '(&.[Pk:"
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publicfinalstaticint PAGESIZE = 30; v~ZdMQvwt
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privateint pageSize = PAGESIZE; U $X"W'
id&;
privateList items; MBXumc_g
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privateint totalCount; !4]wb!F
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privateint[] indexes = newint[0]; =4m?RPb~b
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privateint startIndex = 0; +<|6y46
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public PaginationSupport(List items, int e6QUe.S
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totalCount){ <k6Zx-6X<
setPageSize(PAGESIZE); ZnI_<iFR*
setTotalCount(totalCount); F^3Q0KsT
setItems(items); V
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setStartIndex(0); >q[ (UV
} M7fw/i
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public PaginationSupport(List items, int iZwt,)(
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totalCount, int startIndex){ O9dIobu4
setPageSize(PAGESIZE); a~9U{)@F
setTotalCount(totalCount); sD_Z`1
setItems(items); /F4rbL^:
setStartIndex(startIndex); f,k'gM{K
} &LwR9\sh
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public PaginationSupport(List items, int MU<Y,4/k
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totalCount, int pageSize, int startIndex){ ] 06LNE
setPageSize(pageSize); i~M CY.F
setTotalCount(totalCount); M`9qo8zCi
setItems(items); iLws;3UX;x
setStartIndex(startIndex); S c_*L<$
} @vCPX=c
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publicList getItems(){ ,<d[5;7x
return items; q+>{@tP9
} =^|^"b
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publicvoid setItems(List items){ V ;
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this.items = items; z\sy~DM;>
} 0 j:8Ve
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publicint getPageSize(){ nz3j";d
return pageSize; p'0jdb :S
} o6'I%Gs
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publicvoid setPageSize(int pageSize){ &<_*yl p
this.pageSize = pageSize; A{bt
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} qb]n{b2
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publicint getTotalCount(){ p&>*bF,
return totalCount; \A6MVMF8
} q?nXhUD
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publicvoid setTotalCount(int totalCount){ kn^RS1m
if(totalCount > 0){ +%OINMo.A
this.totalCount = totalCount; J{
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int count = totalCount / k?;A#L~
JN .\{ Y
pageSize; /!=uM.
if(totalCount % pageSize > 0) TUw^KSa
count++; u}\F9~W-{
indexes = newint[count]; }/nbv;)
for(int i = 0; i < count; i++){ X};m \Bz
indexes = pageSize * ] QGYEjW
wc*5s7_
i; j&6,%s-M`a
} GvF8S MO[x
}else{ '_lyoVP
this.totalCount = 0; 1XSA3;ZEc
} &=Gz[1
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} : ^F+mQN
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publicint[] getIndexes(){ 5|my}.TR
return indexes; J;W(}"cFq
} ?l!L
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publicvoid setIndexes(int[] indexes){ %0fF_OU
this.indexes = indexes; `KqMcAW
} Dd-;;Y1C
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publicint getStartIndex(){ w17\ \[
return startIndex; F[<EXLQ
} Y9Q-<~\z
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publicvoid setStartIndex(int startIndex){ an_qE}P
if(totalCount <= 0) Jkzt=6WZ0
this.startIndex = 0; X6kB
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elseif(startIndex >= totalCount) rbiNp6AdL
this.startIndex = indexes |s-q+q{|
}__g\?Yf
[indexes.length - 1]; !rZO~a0
elseif(startIndex < 0) |R8=yO%(
this.startIndex = 0; (~:k70V5
else{ *%l&'+
this.startIndex = indexes zpV@{%VSj
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[startIndex / pageSize]; :y==O4
} ]sjYxe
} =2] .G Gg
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publicint getNextIndex(){ ?VrZM
int nextIndex = getStartIndex() + r5jiB L~
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pageSize; v_)a=I%o&2
if(nextIndex >= totalCount) IMIZ#/
return getStartIndex(); +-&N<U
else
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return nextIndex; ?Z0T9e<
} /=w9bUj5v
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publicint getPreviousIndex(){ 5!$m3j_,]?
int previousIndex = getStartIndex() - O{ zY(`[
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pageSize; jCDZ$W89
if(previousIndex < 0) _QbLg"O
return0; mr6/d1af_
else !8yw!hA
return previousIndex; AFcsbw
} CP_ ?DyWU
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} xT70Rp(2po
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抽象业务类 GE]fBg
java代码:
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/** k@JDG]R<{
* Created on 2005-7-12 Mez;DKJ`
*/ &,4]XT
package com.javaeye.common.business; ^wPKqu)^
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import java.io.Serializable; oEbgyT gB
import java.util.List; oJe9H <
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import org.hibernate.Criteria; g9|B-1[
import org.hibernate.HibernateException; [/hS5TG|7
import org.hibernate.Session; (mz5vzyw
import org.hibernate.criterion.DetachedCriteria; Z)EmX=
import org.hibernate.criterion.Projections; mt3j- Mw
import xnmIo?
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org.springframework.orm.hibernate3.HibernateCallback; J;h4)w~9H3
import Z]D O
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org.springframework.orm.hibernate3.support.HibernateDaoS g66=3c9</6
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upport; @GqPU,RO
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import com.javaeye.common.util.PaginationSupport; [Av#Z)R
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public abstract class AbstractManager extends Mnyg:y*=
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HibernateDaoSupport { %^[45e
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privateboolean cacheQueries = false; Kdh(vNB>
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privateString queryCacheRegion; Y,RED5]t
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publicvoid setCacheQueries(boolean >Z?fX
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cacheQueries){ # eqt{
this.cacheQueries = cacheQueries; F,Y,0f@4U9
} VvN52
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publicvoid setQueryCacheRegion(String ATCFdtNc
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queryCacheRegion){ In^MZ)?
this.queryCacheRegion = "}Kvx{L8
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queryCacheRegion; i)f3\?,,
} ]'V8{l
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publicvoid save(finalObject entity){ dQ ?4@
getHibernateTemplate().save(entity); qKt8sxg
} V&vU her0
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publicvoid persist(finalObject entity){ (-*NRY3*
getHibernateTemplate().save(entity); Q:eIq<erY
} H+vONg
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publicvoid update(finalObject entity){ LSb3w/3M
getHibernateTemplate().update(entity); {PgB~|W
} R 5 47
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publicvoid delete(finalObject entity){ @3KVYv,q
getHibernateTemplate().delete(entity); <q
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} E0[!jZ:c
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publicObject load(finalClass entity, SY|r'8Z%Q
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finalSerializable id){ [1B F8:
return getHibernateTemplate().load J9S9rir&
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(entity, id); mj5$ 2J
} Ol H{!
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publicObject get(finalClass entity, JbpKstc;
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finalSerializable id){ I7TdBe-
return getHibernateTemplate().get 2Fi>nJ
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(entity, id); bcL>S$B
} wGa0w*$
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publicList findAll(finalClass entity){ B%gk[!d}8
return getHibernateTemplate().find("from W7.O(s,32
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" + entity.getName()); [0.>:wT
} W"Hjn/xSS
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publicList findByNamedQuery(finalString y _J~n 9R
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namedQuery){ o_&.R
return getHibernateTemplate |t CD@M
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().findByNamedQuery(namedQuery); 6-va;G9Fc
} h h}%Z=
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publicList findByNamedQuery(finalString query, HX\@Qws
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finalObject parameter){ >"?HbR9
return getHibernateTemplate 0h!2--Aur
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().findByNamedQuery(query, parameter); @_^QBw0
} %Y%+K5;AZ
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publicList findByNamedQuery(finalString query, 4 q}1
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finalObject[] parameters){ k$:QpTg[
return getHibernateTemplate f^](D'L?D
YS=|y}Q|7d
().findByNamedQuery(query, parameters); [W=%L:Ea
} IcZ_AIjlk
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publicList find(finalString query){ d='z^vHK
return getHibernateTemplate().find piJ/e
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(query); 1 Uz'=a
} !OWVOq8
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publicList find(finalString query, finalObject 'KpCPOhfR
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parameter){ dvxD{UH
return getHibernateTemplate().find /-z_"G
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(query, parameter); Le9r7O:
} 1~8F&
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public PaginationSupport findPageByCriteria $>v^%E;Y4
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(final DetachedCriteria detachedCriteria){ FW#Lf]FJ
return findPageByCriteria -aG( Yx
/ :"%m:-P
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ek_k_!
} X
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7
public PaginationSupport findPageByCriteria Iu|G*~\
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(final DetachedCriteria detachedCriteria, finalint OdgfvHDgW
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startIndex){ ]n?a h
return findPageByCriteria D}"\nCz}y&
j)Kk:BFFY
(detachedCriteria, PaginationSupport.PAGESIZE, a1ZGMQq!
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startIndex); OH5
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} ( f8g}2
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public PaginationSupport findPageByCriteria ~B>I?j
%r6LU<;1@
(final DetachedCriteria detachedCriteria, finalint F<BhN+U
%s$_KG !&
pageSize, JeMhiY}
finalint startIndex){ ,iCd6M{
return(PaginationSupport) o"[P++qd
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getHibernateTemplate().execute(new HibernateCallback(){ NrVQK}%K
publicObject doInHibernate NF0IF#;a
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(Session session)throws HibernateException { U"-mLv"|
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); 25ul,t_Du
int totalCount = s .^9;%@$J
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((Integer) criteria.setProjection(Projections.rowCount Bp^>R`,
vtR<(tOu@
()).uniqueResult()).intValue(); vb: '%^v
criteria.setProjection <| |Lj
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(null); *[
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List items = W~W^$A
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criteria.setFirstResult(startIndex).setMaxResults @U;-5KYYi
v7O{8K+
(pageSize).list(); x0.&fCh%
PaginationSupport ps = z-[Jbjhd
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new PaginationSupport(items, totalCount, pageSize, aEXV^5;,pJ
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startIndex); qfC9 {gu
return ps; 0J$wX yh
} ""Drf=]
}, true); 1>a^Q
} ;}f%b E
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public List findAllByCriteria(final cWFvYF
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DetachedCriteria detachedCriteria){ a9QaF s"
return(List) getHibernateTemplate @pytHN8( $
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().execute(new HibernateCallback(){ CvQ LF9|
publicObject doInHibernate 1Od:I}@
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(Session session)throws HibernateException { A6iyJFmD
Criteria criteria = i=o>Bl@f
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detachedCriteria.getExecutableCriteria(session); \_x)E]D
return criteria.list(); 51x^gX|
} ui9gt"qS`
}, true); +6gS]
} b@1QE
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public int getCountByCriteria(final l*'8B)vN2
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DetachedCriteria detachedCriteria){ Z|8f7@k{|+
Integer count = (Integer) KN}[N+V>
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getHibernateTemplate().execute(new HibernateCallback(){ 7UQD02
publicObject doInHibernate = 1}-]ctVn
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(Session session)throws HibernateException { DVTzN(gO*~
Criteria criteria = CdZ;ZR
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detachedCriteria.getExecutableCriteria(session); i;|%hDNWA
return ACyQsmqm:
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criteria.setProjection(Projections.rowCount !+>yCy$~_
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()).uniqueResult(); JAB]kNvI
} lq.0?(
}, true); pQVi&( M
return count.intValue(); WM@uxe,
} <wE2ly&x
} Jr''S}@|x
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用户在web层构造查询条件detachedCriteria,和可选的 (Nik(Oyj"
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 l}O`cC
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PaginationSupport的实例ps。 /$9/,5|EA
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ps.getItems()得到已分页好的结果集 qtgK}*9ptv
ps.getIndexes()得到分页索引的数组 %mcuYR'D}
ps.getTotalCount()得到总结果数 G^2"\4R]p
ps.getStartIndex()当前分页索引 zG@!(
ps.getNextIndex()下一页索引 G&uj}rj
ps.getPreviousIndex()上一页索引 t?0=;.D
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} KMdfA
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 TTOd0a
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 G*"N}M1)
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一下代码重构了。 L7jz^g^
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我把原本我的做法也提供出来供大家讨论吧: ol[{1KT{
J,~)9Kh$
首先,为了实现分页查询,我封装了一个Page类: 5#d(_
java代码: g|+G(~=e|
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/*Created on 2005-4-14*/ 6u.b?_u
package org.flyware.util.page; r+lY9l
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/** jr9ZRHCU
* @author Joa 72{kig9c
* NK4ven7/
*/ `r]Cd
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publicclass Page { {(tE pr
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/** imply if the page has previous page */ @DUdgPA
privateboolean hasPrePage; )0GnTB;5Z
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/** imply if the page has next page */ tlcA\+%)
privateboolean hasNextPage; XsR%_eT
+2?0]6EQ
/** the number of every page */ jOuv\$
privateint everyPage; 4u(}eE
f7
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/** the total page number */ 1L9^N
privateint totalPage; 4p-$5Fk8}
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/** the number of current page */ 4]+ ^K`
privateint currentPage; 6F(yH4
7"[lWC!As5
/** the begin index of the records by the current FVD}9ia
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query */ (Dn-vY'
privateint beginIndex; .(hb8 rCM
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/** The default constructor */ e;pNB
public Page(){ txgGL'
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} CTI(Kh+
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/** construct the page by everyPage lZua"Ju
* @param everyPage c]"B)I1L
* */ %-*vlNC )
public Page(int everyPage){ *K98z ?
this.everyPage = everyPage; tEEhSG)s%
} Ey n3Vv?v
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/** The whole constructor */ fwnpmuJ
public Page(boolean hasPrePage, boolean hasNextPage, Sx ~_p3_5U
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int everyPage, int totalPage, cp2fDn
int currentPage, int beginIndex){ HdLkof2i
this.hasPrePage = hasPrePage; wYxizNv,
this.hasNextPage = hasNextPage; ef.lM]cO
this.everyPage = everyPage; )N6R#
this.totalPage = totalPage; zbi
this.currentPage = currentPage; \=_8G:1
this.beginIndex = beginIndex; 0Fw\iy1o
} ps[6)d)o
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/** 'wZy: c
* @return -'N#@Wdr
* Returns the beginIndex. Nb8<8O
^
*/ E*I]v
publicint getBeginIndex(){ dSL %%
return beginIndex; S]o
} ?dmMGm0T9
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/** 0!VLPA:
* @param beginIndex X
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* The beginIndex to set. 4l1=l#\S
*/ u}rot+)%
publicvoid setBeginIndex(int beginIndex){ 6f>l~$
this.beginIndex = beginIndex; YBCjcD[G
} q7]WR(e
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/** LAKZAi%O0
* @return ~ghz%${`
* Returns the currentPage. ^VIUXa
*/ G9a%N
publicint getCurrentPage(){
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return currentPage; vX/A9Qi,U.
} 2%qn!+.
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/** 7
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* @param currentPage 0C p}
* The currentPage to set. oU@ljSD
*/ +{%4&T<nHw
publicvoid setCurrentPage(int currentPage){ 55cldo
this.currentPage = currentPage; X@:fW @
} M$W#Q\<*#r
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/** L@_">'pR
* @return &+j^{a
* Returns the everyPage. (rG1_lUDu
*/ >YBpB,WND
publicint getEveryPage(){ `eWcp^|
return everyPage; ._&lG3'
} N.G*ii\
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/** !TOi]`vqc
* @param everyPage f0`'
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* The everyPage to set. s4gNS
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*/ UvZ@"El
publicvoid setEveryPage(int everyPage){ $i@EfujY
this.everyPage = everyPage; D,n}Qf!GYk
} U&n>fXTHn
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/** B# ?2,
* @return n2{{S(N
* Returns the hasNextPage. @."o:K
*/ VqL
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publicboolean getHasNextPage(){ 6)U&XWH0
return hasNextPage; {g- DM}q
} 4LEE
/
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/** E.`dk.
* @param hasNextPage {?mQqoZ?.
* The hasNextPage to set. y<1$^Y1/)
*/ Z&w^9;30P
publicvoid setHasNextPage(boolean hasNextPage){ kNj3!u$
this.hasNextPage = hasNextPage; V"H7zx
} NoO+xLHw8
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/** uvDoo6'
* @return 1bJ]3\
* Returns the hasPrePage. '
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*/ 7F(F.ut
publicboolean getHasPrePage(){ S9NN.dKu
return hasPrePage; m_$I?F0
} +qj*P9
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/** WQ}!]$<"y
* @param hasPrePage U('<iw,Yy
* The hasPrePage to set. .Sr:"S rT
*/ (Q5@MfK`
publicvoid setHasPrePage(boolean hasPrePage){ T#n1@FgC
this.hasPrePage = hasPrePage; zf,%BI[Hr
} U[QD!
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/** +%Yc4
* @return Returns the totalPage. 8M|)ojH
* 2ly,l[p8
*/ eq~c
publicint getTotalPage(){ 6#)Jl
return totalPage; T_x+sv=|X!
} @qPyrgy
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/** Nr24[e
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* @param totalPage sk
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* The totalPage to set. {?/8jCVd
*/ `GQiB]Z
publicvoid setTotalPage(int totalPage){ ,![Du::1
this.totalPage = totalPage; ZJ9Jf2 c
} P$3=i`X!nw
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} C5+`<
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 tw/#ENo
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个PageUtil,负责对Page对象进行构造: 28R>>C=R
java代码: 'xbERu(Y
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/*Created on 2005-4-14*/ +^*5${g;@H
package org.flyware.util.page; F@$RV_M
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import org.apache.commons.logging.Log; ~zxwg+:QO
import org.apache.commons.logging.LogFactory; M%&A.j[
/S]:dDY9K
/** [vWkAJ'K
* @author Joa eOehgU5x
* )[^y
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*/ \-
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publicclass PageUtil { "%E-X:Il#
y|6@-:B.
privatestaticfinal Log logger = LogFactory.getLog `~_H=l9{
S,9NUt
(PageUtil.class); E69:bQ94u
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/** (/U)>%n
* Use the origin page to create a new page Jq$_=X&
* @param page +YkW[a\4
* @param totalRecords ,\lYPx\P[
* @return %o@['9U[j
*/ vm\wO._
publicstatic Page createPage(Page page, int (Pv`L
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totalRecords){ TCHqe19?
return createPage(page.getEveryPage(), f v E+.{
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page.getCurrentPage(), totalRecords); dG\U)WA(p
} ]<kupaRQ
pw,O"6J*
/** Jcz]J)|5v
* the basic page utils not including exception @S}/g/+2
b96t0w!cs
handler 7uPZuXHxcu
* @param everyPage r$GPYyHK
* @param currentPage l'*^$qc
* @param totalRecords /l,+oG%\
* @return page ?P""KVpo
*/ XM6".eF)M
publicstatic Page createPage(int everyPage, int <NG/i i=
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currentPage, int totalRecords){ d4Co^A&
everyPage = getEveryPage(everyPage); `DLp<_z>
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, ?a5h iN0
ic*->-!
currentPage); 8!4~T,9G
int totalPage = getTotalPage(everyPage, iq"ob8.
PiMKu|,3
totalRecords); /&PKCtm&~
boolean hasNextPage = hasNextPage(currentPage, T'ED$}N>~
0xJ7M.
totalPage); /?KtXV>]
boolean hasPrePage = hasPrePage(currentPage); ;V_.[aX
2+?T66 g
returnnew Page(hasPrePage, hasNextPage, sm 's-gD
everyPage, totalPage, G2.|fp_}pG
currentPage, pheE^jUr
GE1i+.+-.
beginIndex); X'fuF2owd
} Y^52~[w~
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privatestaticint getEveryPage(int everyPage){ M|\^UF2e
return everyPage == 0 ? 10 : everyPage; o#qH2)tb
} Y3-gUX*w0
25 CZmsg
privatestaticint getCurrentPage(int currentPage){ 1T ( u
return currentPage == 0 ? 1 : currentPage; Kv(z4 z
} jY7=mAd
*YWk1Cwjo
privatestaticint getBeginIndex(int everyPage, int 00ofHZ
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currentPage){ [SVhtrx|%
return(currentPage - 1) * everyPage; )4l>XlQ&
} '|A|vCRCG
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privatestaticint getTotalPage(int everyPage, int %$@1FlqX;
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totalRecords){ qnB<k,8T
int totalPage = 0; N]NF\7(
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if(totalRecords % everyPage == 0) 2{bhA5L
totalPage = totalRecords / everyPage; bS.s?a
else 4&QUh+F
totalPage = totalRecords / everyPage + 1 ; [J^
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return totalPage; &FSmqE;@^
} m9in1RI%
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privatestaticboolean hasPrePage(int currentPage){ 57wFf-P
return currentPage == 1 ? false : true; {;s;.
} AS)UJ/lC
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privatestaticboolean hasNextPage(int currentPage, kb71q:[
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int totalPage){ \v+u;6cx_
return currentPage == totalPage || totalPage == ~#R9i^Y
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0 ? false : true; E@-ta):
} zN#*G
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} e ^Ds
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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。 F]UQuOR)
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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 j9d!yW
>I}9LyZt
做法如下: xl(@C*.sC1
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 `ltN,?/
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的信息,和一个结果集List: [}OgSP9i
java代码: :_ROJ
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rYY$wA@
/*Created on 2005-6-13*/ LCs__.
package com.adt.bo; [U>@,BH
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import java.util.List; 9i5tVOhE
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import org.flyware.util.page.Page; N|mJg[j@7
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/** "9IYB)Js
* @author Joa (-0ePSOG
*/ ZrO!L_/
publicclass Result { 6sJw@OaJ
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private Page page; 0V$k7H$Z
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private List content; ?WUF!Jk
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/** z0%\OhuCcf
* The default constructor lx |5?P
*/ ,E;;wdIt
public Result(){ )? =YT
super(); BHA923p?
} ]5Qy
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/** 8j5<6Cv_
* The constructor using fields /ASaB
* v>Lm;q(
* @param page qJPT%r
* @param content YO+{,$
*/ c$:1:B9\
public Result(Page page, List content){ 0nJE/JZ
this.page = page; z'7[T ie
this.content = content; K4Sk+
v
} $P z`$~
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/** vxFTen{-F
* @return Returns the content. @%/]Q<<q
*/ j}1zdA
publicList getContent(){ mYxyWB
return content; dq\FBwfe
} |4(~%| 8{
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/** vb
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* @return Returns the page. 6e,xDr
*/ =<}<Ny
public Page getPage(){ K+*Q@R D
return page; 6$U]9D
} /./"x~@
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/** j.e0;!
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* @param content uo\ .7[1
* The content to set. F&RgT1*
*/ L<^j"!0
public void setContent(List content){ = ?D(g
this.content = content; tVuWVJ4M
} _"@CGXu
;0rGiWC#
/** 'e)^m}:?D
* @param page j/`94'Y
* The page to set. k%s_0
@
*/ a"N4~?US
publicvoid setPage(Page page){ Y;4!i?el
this.page = page; ldha|s.*
} Tm}rH]F&
} +mj*o(
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ncu`vYI.
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2. 编写业务逻辑接口,并实现它(UserManager, dZ#&YG)?e
{7u[1[L1
UserManagerImpl) j#r6b]k(Hv
java代码: YHNR3
Snp|!e
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/*Created on 2005-7-15*/ Hnknly
package com.adt.service; r{\1wt
7SD Fz}
import net.sf.hibernate.HibernateException; &