Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 C1ZuDL)e
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 % r>v^1Vo
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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 lc8zF5
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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 OoqA`%
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分页支持类: S+*g
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java代码: T5gL
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package com.javaeye.common.util; Fd(o8z8Q
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import java.util.List; kx.8VUoM
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publicclass PaginationSupport { )ld`2)
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publicfinalstaticint PAGESIZE = 30; *MM8\p_PuT
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privateint pageSize = PAGESIZE; N6thbH@
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privateList items; i~sW_f+
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privateint totalCount; |J:kL3g
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privateint[] indexes = newint[0]; UJ^MS4;I3
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privateint startIndex = 0; dZIruZ)x
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public PaginationSupport(List items, int g3Z"ri~!G
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totalCount){ 3@8Zy:[8<
setPageSize(PAGESIZE); 1h,m
setTotalCount(totalCount); t*dd/a
setItems(items); d:{#Dk#
setStartIndex(0); [+.P'6/[$R
} }h=}!R'm
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public PaginationSupport(List items, int 1P6!E*z\
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totalCount, int startIndex){ e4<[|B!O
setPageSize(PAGESIZE); o)r%4YOL
setTotalCount(totalCount); x4^*YZc$,
setItems(items); qtYVX:M@,
setStartIndex(startIndex); h'|J$
} =OR"Bd:O
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public PaginationSupport(List items, int >m'n#=yap
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totalCount, int pageSize, int startIndex){ ,/Usyb,`
setPageSize(pageSize); m!LJK`gA
setTotalCount(totalCount); Y'eE({)<K
setItems(items); r[W
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setStartIndex(startIndex); sHn-#SGm
} gl>%ADOB@
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publicList getItems(){ f*E#E=j
return items; gt|:K)[,6
} q)QM+4
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publicvoid setItems(List items){ _sX@BE
this.items = items; JK9 J;c#T
} GS&iSjw
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publicint getPageSize(){ K!jMW
return pageSize; \@F~4,VT
} i/{`rv*K[
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publicvoid setPageSize(int pageSize){ F$nc9x[S
this.pageSize = pageSize; @0&KM|+
} (!"&c*
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publicint getTotalCount(){ u 1)
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return totalCount;
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} J[{?Y'RUM
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publicvoid setTotalCount(int totalCount){ <&MY/vV
if(totalCount > 0){ F*J@OY8i
this.totalCount = totalCount; ,]H2F']4Z
int count = totalCount / :V
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pageSize; E9~}%&
if(totalCount % pageSize > 0) PCs`aVZ
count++; cu )w6!f
indexes = newint[count]; wq
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for(int i = 0; i < count; i++){ V8}jFib
indexes = pageSize * {2=f,,|+f
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} W+`T:Mgh
}else{ $c1xh.
this.totalCount = 0; =.\PG[
} ?*dt JL
} ck\TTNA
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publicint[] getIndexes(){ Dt glPo_(
return indexes; -a`PW
} &[qJ=HMm I
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publicvoid setIndexes(int[] indexes){ 4"d'iY
this.indexes = indexes; j:P(,M[
} +Z1y1%a
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publicint getStartIndex(){ <Oihwr@5<
return startIndex; <}('w/
} b/6!>qMMk%
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publicvoid setStartIndex(int startIndex){ ePscSMx&
if(totalCount <= 0) v0u, :eZ4
this.startIndex = 0; UJ7{FN=@t
elseif(startIndex >= totalCount) cllnYvr3
this.startIndex = indexes :7[4wQDt4
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[indexes.length - 1]; r O-=):2
elseif(startIndex < 0) K_o[m!:jU
this.startIndex = 0; N-YCOSUu
else{ z2IKd'Wy
this.startIndex = indexes 5\.w\
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[startIndex / pageSize]; q:<vl^<j
} ~=k?ea/>
} q"$C)o
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publicint getNextIndex(){ +~\ 1g^h
int nextIndex = getStartIndex() + G6q*U,
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pageSize; .M( [n-
if(nextIndex >= totalCount) *_H^]wNJG
return getStartIndex(); aK?PK }@
else $*c!9Etl4
return nextIndex; @BoZZ
} $VnPs!a
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publicint getPreviousIndex(){ >?|c>HGX
int previousIndex = getStartIndex() - {VT**o
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pageSize; pz ~REsx
if(previousIndex < 0) Hd89./v`:
return0; Mt\.?V:
else `9mc+
return previousIndex; .Zm de*b
} *^i"q\n5(
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} bEB9J-
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抽象业务类 I]6,hygs
java代码: $ 9
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/** fR#W#n#m
* Created on 2005-7-12 6wH:jd9,
*/ U$Od)
package com.javaeye.common.business; o(eh.
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import java.io.Serializable; d-'BT(@:
import java.util.List; FE3uNfQs|
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import org.hibernate.Criteria; x<1t/o
import org.hibernate.HibernateException; yM#
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import org.hibernate.Session; O PJ(ub
import org.hibernate.criterion.DetachedCriteria; 6[\1Nzy>
import org.hibernate.criterion.Projections; \JDxN
import $%.,=~W7
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org.springframework.orm.hibernate3.HibernateCallback;
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import MN[D)RKh;
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org.springframework.orm.hibernate3.support.HibernateDaoS _@! yj
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upport; to(lE2`.da
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import com.javaeye.common.util.PaginationSupport; KskPFXxP
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public abstract class AbstractManager extends ~WKWx.ul
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HibernateDaoSupport { p
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privateboolean cacheQueries = false; DqA$%b
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privateString queryCacheRegion; $J =`fx
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publicvoid setCacheQueries(boolean mNKcaM?h
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cacheQueries){ 6f)7*j~
this.cacheQueries = cacheQueries;
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} g1I8_!}~
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publicvoid setQueryCacheRegion(String &"d
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queryCacheRegion){ JfRqOEP4Y
this.queryCacheRegion = uoTc c|Kc
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queryCacheRegion; ]sJjV
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} 't+'rG6x
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publicvoid save(finalObject entity){ 5h6-aQU[
getHibernateTemplate().save(entity); T[kS;-x
} >OKc\m2%Q
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); q@i.4>x
} W/.Wp|C}K3
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publicvoid update(finalObject entity){ y\Wp}}
getHibernateTemplate().update(entity); Sobp;OZ5
} p~OX1RBI
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publicvoid delete(finalObject entity){ #r QT)n
getHibernateTemplate().delete(entity); BiA^]h/|
} VVqpzDoXG
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publicObject load(finalClass entity, !'Ww%ZL\
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finalSerializable id){ b6g/SIae
return getHibernateTemplate().load 7%W@Hr,%F
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(entity, id); j-v/;7s/B
} *~^%s+b
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publicObject get(finalClass entity, @B9#Hrc
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finalSerializable id){ U["IXR#
return getHibernateTemplate().get aT8A+=K6
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(entity, id); rd^j<
} ~R7{gCqdr
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publicList findAll(finalClass entity){ +f,I$&d.V
return getHibernateTemplate().find("from OT#foP
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" + entity.getName()); @'"7[k!y;
} W3&~[DS@~
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publicList findByNamedQuery(finalString yppXecFJ
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namedQuery){ 4g?qKoc
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return getHibernateTemplate ,&jjpeZP
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().findByNamedQuery(namedQuery); =6BI[_0
} hroRDD
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publicList findByNamedQuery(finalString query, 8},fu3Z
JB HnJm
finalObject parameter){ r6L
return getHibernateTemplate !%QbE[Kl>
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().findByNamedQuery(query, parameter); !={QL :
} ]%UAN_T
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publicList findByNamedQuery(finalString query, jyC>~}?
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finalObject[] parameters){ CN7qqd
return getHibernateTemplate S.^x)5/,,T
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().findByNamedQuery(query, parameters); BF
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} >2tosxH M
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publicList find(finalString query){ N}q*(r!q<
return getHibernateTemplate().find K\$z,}0
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(query); #e6x_o|
} ? \NT'CG
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publicList find(finalString query, finalObject yJw4!A 1!
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parameter){ <@=w4\5j9
return getHibernateTemplate().find Yq:TWeZD
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(query, parameter); UbSD?Ew@35
} e{d$OzT) V
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public PaginationSupport findPageByCriteria n/IDq$/P
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(final DetachedCriteria detachedCriteria){ \K(#
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return findPageByCriteria ]BBjFs4#
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); U&y?3
} )X-TJ+d
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public PaginationSupport findPageByCriteria vC5y]1QDd
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(final DetachedCriteria detachedCriteria, finalint N9cUlrDO
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startIndex){ w~VqdB
return findPageByCriteria >HQ<KFA
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[+_T{
(detachedCriteria, PaginationSupport.PAGESIZE, uJ/&!q<3
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startIndex); k'+Mc%pg4E
} `<d{(9:+
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public PaginationSupport findPageByCriteria [7SR2^uf<j
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(final DetachedCriteria detachedCriteria, finalint t~FOaSt
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pageSize, 00@y,V_]
finalint startIndex){ Iw) 'Yyg
return(PaginationSupport) QOY M/1U
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getHibernateTemplate().execute(new HibernateCallback(){ 9`sIE _%+
publicObject doInHibernate j4.deQ,
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(Session session)throws HibernateException { (.B+U'6
Criteria criteria = `=cOTn52
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detachedCriteria.getExecutableCriteria(session); Smlf9h&
int totalCount = 0|_d{/VK4
\ )n'Ywr
((Integer) criteria.setProjection(Projections.rowCount h ?%]uFJC
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()).uniqueResult()).intValue(); Vy[ m%sEP
criteria.setProjection A&6qt
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(null); p8Wik<'^
List items = :IlJQ{=W
'VTLp.~G~
criteria.setFirstResult(startIndex).setMaxResults rfS kQT
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(pageSize).list(); *(sFr E
PaginationSupport ps = w*"h#^1z
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new PaginationSupport(items, totalCount, pageSize, T.p:`}Ma
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startIndex); r*t\\2
return ps; BTu_$5F
} <i!7f26r
}, true); CA{(x(W\:
} COf>H0^%Q
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public List findAllByCriteria(final ESAFsJ$r;
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DetachedCriteria detachedCriteria){ e[a?5,s2
return(List) getHibernateTemplate :F`yAB3
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().execute(new HibernateCallback(){ N^{+1u7
publicObject doInHibernate ,HLgb}~
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(Session session)throws HibernateException { Fb{kql=
Criteria criteria = E|fQbkfw
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detachedCriteria.getExecutableCriteria(session); I2PFJXp_]n
return criteria.list(); S*-/#j
}
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}, true); 7D%}(pX
} A(Ss:7({
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public int getCountByCriteria(final 1Xi.OGl
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DetachedCriteria detachedCriteria){ +(|6Wv
Integer count = (Integer) g$j ZpU
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getHibernateTemplate().execute(new HibernateCallback(){ $m-rn'Q
publicObject doInHibernate h!L6NS_Q,
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(Session session)throws HibernateException { 4D-4BxN*
Criteria criteria = }}'0r2S
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detachedCriteria.getExecutableCriteria(session); (NBq!;_2,x
return )6
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criteria.setProjection(Projections.rowCount xi
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()).uniqueResult(); =,-&h
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} ]wQ#8}zO
}, true); BL^8gtdn
return count.intValue(); Z`)}1|~B
} M[@=m[#a
} AGdFJ>/
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用户在web层构造查询条件detachedCriteria,和可选的 >$yqx1=jW
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 (haYY]W\
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PaginationSupport的实例ps。 <+oTYPgD9
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ps.getItems()得到已分页好的结果集 @N-P[.qL"
ps.getIndexes()得到分页索引的数组 ^<}eONa
ps.getTotalCount()得到总结果数 [*k25N
ps.getStartIndex()当前分页索引 Iw<:
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ps.getNextIndex()下一页索引 dk^Uf84.Gr
ps.getPreviousIndex()上一页索引 kCu" G
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 l?N|Gj;ZFZ
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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 zNs8yMnFr
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一下代码重构了。 -Pr1r
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我把原本我的做法也提供出来供大家讨论吧: VNmQ'EuV}2
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首先,为了实现分页查询,我封装了一个Page类: !Cpy
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java代码: x@ZxV*T^
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/*Created on 2005-4-14*/ >2[\WF*"X
package org.flyware.util.page; 1$*ZN4
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/** Vu/{Hr
* @author Joa C#r1zr6
* Y|NANjEAfm
*/ s
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publicclass Page { 7( &\)qf=n
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/** imply if the page has previous page */ ^rmcyy8;g
privateboolean hasPrePage; 'V=i;2mB*
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/** imply if the page has next page */ tR,&|?0
privateboolean hasNextPage; DRn]>IFU
IwfJDJJ
/** the number of every page */ 8<Y*@1*j
privateint everyPage; W?n)IBj8
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/** the total page number */ tf VK
privateint totalPage; 0.9%m7.m
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/** the number of current page */ Eu4-=2!4
privateint currentPage; =peodj^
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/** the begin index of the records by the current ID-Y*
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query */ RZtY3:FBx|
privateint beginIndex; 0~(K@U>#
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/** The default constructor */ zT\nj&7
public Page(){ [p+]H?(A
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} Pp*:rA"N
< )dqv0=
/** construct the page by everyPage ]Kutuf$t
* @param everyPage Y;X_E7U
* */ m5wfQ_}}ss
public Page(int everyPage){ o_.f7|U!
this.everyPage = everyPage; Z#O )0ou
} ps DY}y\"
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/** The whole constructor */ :7,j%ELic
public Page(boolean hasPrePage, boolean hasNextPage, XYi-o][Mf
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int everyPage, int totalPage, \F$V m'f_
int currentPage, int beginIndex){ r9nyEzk
this.hasPrePage = hasPrePage; " vW4"R6
this.hasNextPage = hasNextPage; ;i)NP X
this.everyPage = everyPage; 'F\@KE-d
this.totalPage = totalPage; 5Iql%~_x
this.currentPage = currentPage; K}vP0O}
this.beginIndex = beginIndex; A#yZh\#
} |6cz r
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/** Ix-bJE6+I,
* @return >FVBn;1
* Returns the beginIndex. {Dc{e5K
*/ Io|3zE*<
publicint getBeginIndex(){ #-]!;sY>
return beginIndex; :>:F6Db"U
} FZt a
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/** /IO<TF(X
* @param beginIndex \]j{
* The beginIndex to set. :i?7RouO
*/
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publicvoid setBeginIndex(int beginIndex){ u8w4e!rKo6
this.beginIndex = beginIndex; `X["Bgk$!T
} MO_-7,.y
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/** ^^9O9]
* @return !-cO0c!
* Returns the currentPage. ,ln=kj
*/ M$ jU-;hRH
publicint getCurrentPage(){ _d[4EY
return currentPage; _Q**4
} q =\3jd
}nsxo5WP
/** dR9[K4`p/
* @param currentPage m]7oTmS
* The currentPage to set. n$*e(
*/ L@|xpq
publicvoid setCurrentPage(int currentPage){ #OQT@uF!
this.currentPage = currentPage; fEWXC|"
} j3Sz+kOf,
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/** z]twh&^1L
* @return TtWE:xE
* Returns the everyPage. Z\\'0yuY(
*/ ^Fn~@'
publicint getEveryPage(){ B24,;2J
return everyPage; xJ);P.
} 7;8#iS/
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/** e5GJ:2sH
* @param everyPage <o aVI?
* The everyPage to set. Vx~N`|yY
*/ #:)yh]MP
publicvoid setEveryPage(int everyPage){ pX/42W
this.everyPage = everyPage; )y .1}R2[
} 'yw7|i2
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/** ~jpdDV&u\
* @return j><8V Qx
* Returns the hasNextPage. b 9%G"?~Zz
*/ X!AD]sK
publicboolean getHasNextPage(){ GyVRe]<>B
return hasNextPage; ,ix> e
} .H33C@
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/** Ec/-f`8
* @param hasNextPage mu>L9Z~(L_
* The hasNextPage to set. i?+>,r@\p
*/ A*a:#'"*N
publicvoid setHasNextPage(boolean hasNextPage){ >!gW]{
this.hasNextPage = hasNextPage; 7`G
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} t0"2Si
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/** Qp5YS
* @return j1sgvh]D
* Returns the hasPrePage. [b?[LK}.
*/ ImG7E
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publicboolean getHasPrePage(){ jgyXb5GY
return hasPrePage; skeXsls
} H!81Pq~
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/** p(8[n^~,i
* @param hasPrePage "%?$BoJR0
* The hasPrePage to set. S_|VlI
*/ q=J8SvSRl
publicvoid setHasPrePage(boolean hasPrePage){ s6YnNJ,SK
this.hasPrePage = hasPrePage; :W6R]y
} KB\A<(o,
+FGw)>g8'm
/** 5/f"dX
* @return Returns the totalPage. gNj~o^6|@
* jg3X6 /'
*/ z7PmyU
>
publicint getTotalPage(){ q(nPI
return totalPage; 0+m4
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} <W2YG6^i
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/** O V+|j
* @param totalPage g4U`Qf3
* The totalPage to set. ol #4AU`
*/ "P9SW?',
publicvoid setTotalPage(int totalPage){ W02t6 DW
this.totalPage = totalPage; +DR,&;
} !=B=1th4
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} [izP1A$r#Q
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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 :vWixgLg
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个PageUtil,负责对Page对象进行构造: 1m\ihU
java代码: L_(Y[!
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/*Created on 2005-4-14*/ |k[hk
package org.flyware.util.page; hha!uD~(
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import org.apache.commons.logging.Log; '6zk>rN
import org.apache.commons.logging.LogFactory; 9'I$8Su
C%T$l8$
/** \*i[m&3;q
* @author Joa ZhnRsn9
* FrL
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*/ #_9Jam%M
publicclass PageUtil { 9X ^D(
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privatestaticfinal Log logger = LogFactory.getLog NB)$l2<d
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(PageUtil.class); *T:gx:Sg/
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/** =t!$72g\
* Use the origin page to create a new page +T*]!9%<`:
* @param page ^Sj*
* @param totalRecords $-l\&V++F
* @return &l;wb.%ijW
*/ _2p D
publicstatic Page createPage(Page page, int 'M=c-{f~
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totalRecords){ M?I^Od'8
return createPage(page.getEveryPage(), 96P3B}Dk
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page.getCurrentPage(), totalRecords); Z0!yTM/C
} cK _:?G
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/** 2y` :#e`x1
* the basic page utils not including exception je`w$ ^w
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handler Q2jl61d_9
* @param everyPage ?<h|Q~JH
* @param currentPage c3X8Wi7m
* @param totalRecords csCi0'u
* @return page .~jn
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*/ p5?8E$VHV
publicstatic Page createPage(int everyPage, int /}&@1
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currentPage, int totalRecords){ =! P
everyPage = getEveryPage(everyPage); fF.qQTy;7
currentPage = getCurrentPage(currentPage); oaMh5FPy
int beginIndex = getBeginIndex(everyPage, kXY p.IVA
l>{+X )
currentPage); (rB?@:zN
int totalPage = getTotalPage(everyPage, OJTEvb6nPg
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totalRecords); ,`.`}'
boolean hasNextPage = hasNextPage(currentPage, w8298Kl
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totalPage); .In8!hjYy4
boolean hasPrePage = hasPrePage(currentPage); <h[l)-86
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returnnew Page(hasPrePage, hasNextPage, kp>AZVk
everyPage, totalPage, Qu6Q)dZ<
currentPage, <F#/wU^9
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beginIndex); ` 8OA:4).
} QCVwslj,K
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privatestaticint getEveryPage(int everyPage){ w?Nx^)xX
return everyPage == 0 ? 10 : everyPage; q@8j[15
} Yt#e[CYnu
81&5g'
privatestaticint getCurrentPage(int currentPage){ !Q" 3B6
86
return currentPage == 0 ? 1 : currentPage; +t`QHvxv
} l!9G
]xf|xs
privatestaticint getBeginIndex(int everyPage, int ,.PW
qfb
zm`^=cV
currentPage){ oMer+=vH
return(currentPage - 1) * everyPage; x"xtILrI
} ?>
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privatestaticint getTotalPage(int everyPage, int :"e,&
%
3|g]2|~w@h
totalRecords){ mbCY\vEl
int totalPage = 0; 2%oo.?!R
m(c5g[6nO
if(totalRecords % everyPage == 0) e Zb8x
totalPage = totalRecords / everyPage; *3r{s'm
else 8jxs%N,aI
totalPage = totalRecords / everyPage + 1 ; PN@[k:5(
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return totalPage;
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} A"`(^#a
.f~x*@
privatestaticboolean hasPrePage(int currentPage){ q9mYhT/Im
return currentPage == 1 ? false : true; '.&z y#
} .-W_m7&}
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privatestaticboolean hasNextPage(int currentPage, i][af
? W`?F
int totalPage){ Vg^@6zU
return currentPage == totalPage || totalPage == +""8aA
JkM f+!
0 ? false : true; Mk"V%)1k
} 2~BId&]
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?]bZ6|;2
} I%q&4L7pj
7
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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。 hc4W|Ofj
ND|!U#wMNV
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 DTw3$:
3%$nRP
X
做法如下: V/jEMJNks
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Q<F-l.q
_a3,Zuv
的信息,和一个结果集List: ;2=H7dq
java代码: RO1xcCp
9G'Q3?
z
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/*Created on 2005-6-13*/ "77 j(Vs9
package com.adt.bo; `1$7. ydQ
Vgh_F8G!V
import java.util.List; RW@sh9
k 8Swra?j
import org.flyware.util.page.Page; k!lz_Y
'nFqq:2Xa
/** ZJxUv
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* @author Joa (|PxR#{l<
*/ qq+fUfB2:
publicclass Result { b6k'`vLA
v!pT!(h4
private Page page; p ^U:O&U(
2@ <x%T
private List content; 8R6!SB
JRC+>'}Xj
/** }"'^.FG^_
* The default constructor yn[^!GuJ_
*/ fi2@`37PM
public Result(){ n>Rt9
super(); x@I(G "
} U&D"fM8
)&j4F)
/** 7O)U(<70
* The constructor using fields 5$e|@/(0
* Jz!8Xg%a
* @param page [Pu~kiN
* @param content [kyF |3k~
*/ CjtXU=}A
public Result(Page page, List content){ /8GgEW9Q~G
this.page = page; f@R j;R~Jp
this.content = content; C#<:x!
} XZv(B^
GB(o)I#h
/** ^+JpI*,
* @return Returns the content. <.0-K_
*/ /hef3DV5I
publicList getContent(){ (= H%VXQH
return content; @eRR#S
} A3p@hQl
XF{ g~M
/** &cSTem
0
* @return Returns the page. *N .f_s
*/ k;w1y(
public Page getPage(){ LFCcV<~
return page; jB*%nB*x
} SsDe\"?Q
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/** /#z5bo
* @param content *7Ct#GC
* The content to set. !_VKJZuH
*/ 6uCa iPV
public void setContent(List content){ G}d-L!YbE'
this.content = content; ] ZGP
} OAMsqeWYA
){|Bh3XV
/** -aDGXQM{~
* @param page )oJn@82C|
* The page to set. NKD<VMcqw
*/ XYtDovbv&
publicvoid setPage(Page page){ I
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this.page = page; +_tK \MN
} 66*/"dBwm
} 0b9;vlGq$
PpD ?TAlA
6fhH)]0
0Zp)
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2. 编写业务逻辑接口,并实现它(UserManager, ~6z<tyD^
5A,@$yp+
UserManagerImpl) W3s>+yU
java代码: V?Y;.n&y
"d60IM#N?
'c3P3`o,;
/*Created on 2005-7-15*/ UI}v{05]
package com.adt.service; xJtblZ1sr
_5(lp} s
import net.sf.hibernate.HibernateException; sK8=PZ\
n=#AH;42
import org.flyware.util.page.Page; =T'N6x5@
NGIbUH1[
import com.adt.bo.Result; =X[]0.I%
j:# wt70
/** `9BZ))Pg
* @author Joa ?El8:zt? |
*/ _FXvJ}~m
publicinterface UserManager { f]MKNX
)?#*GMWU
public Result listUser(Page page)throws cRPW
;/w-7O:
HibernateException; QH:k5V~
pj:s+7"t
} 4}@J]_]Z
n $RhD93
qjQR0MC
1zwk0={x-%
64Gd^.Z
java代码: ' NyIy:
(_h<<`@B
C7#ji"t
/*Created on 2005-7-15*/ )[&'\SOO
package com.adt.service.impl; ocCq$%Ka
6%bZZTP`
import java.util.List; lXH?*
e P]L
import net.sf.hibernate.HibernateException; #=mLQSiQ
yd#SB) &
import org.flyware.util.page.Page; (}ObX!,
import org.flyware.util.page.PageUtil; Y5nj _xQJL
~NT2QY5!K
import com.adt.bo.Result; eT33&:n4
import com.adt.dao.UserDAO; )Qe<XJH!
import com.adt.exception.ObjectNotFoundException; 1h uU7xuf
import com.adt.service.UserManager; dU`kJ,=Z
M0Y#=u.
/** +XV7W=
* @author Joa {j$ :9 H
*/
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publicclass UserManagerImpl implements UserManager { [B<htD&
LpCJfQ
private UserDAO userDAO; a"7zz]XO2
N 4Kj)E@
/** 2d),*Cvf
* @param userDAO The userDAO to set. nn[OC=cDN
*/ ]-ad\PI$
publicvoid setUserDAO(UserDAO userDAO){ c>I(6$
this.userDAO = userDAO; %d-|C.
} L'(ei7Z
7i-G5%w7
/* (non-Javadoc) \ZN> 7?Vs
* @see com.adt.service.UserManager#listUser ncw)VH;_-
SI_u0j4%*
(org.flyware.util.page.Page) uG-t)pej
*/ vmEbk/Vy
public Result listUser(Page page)throws {A<pb{<u
P/%5J3_,
HibernateException, ObjectNotFoundException { yN-o?[o
int totalRecords = userDAO.getUserCount(); X5[.X()M4
if(totalRecords == 0) v\&C]W]
throw new ObjectNotFoundException "[A]tklP
^j~CYzmt
("userNotExist"); =CBY_
page = PageUtil.createPage(page, totalRecords); MZJ@qIg[Y
List users = userDAO.getUserByPage(page); v_U+wga
returnnew Result(page, users); i2bkgyzB.
} Xy(8}
`Hlv*" w$
} ZC7ZlL_
0iS"V^aH
vs=8x\W
*vFXe_.
B \WIoz;'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 \%],pZsA ~
tW$Di*h
询,接下来编写UserDAO的代码: dWKjVf
3. UserDAO 和 UserDAOImpl: wE*o1.
java代码: 9NXL8QmC8
2TQyQ%
MS Qz,nn
/*Created on 2005-7-15*/ {>EM=ZZfg
package com.adt.dao; RaT.%:CRm
M~h^~:Lk
import java.util.List; :~"Dwrui
O@9<7@h+Nl
import org.flyware.util.page.Page; oItEGJ|
<GdQ""X
import net.sf.hibernate.HibernateException; 4hl`~&yDf
z4!Y9
/** FaA'%P@
* @author Joa n]nb+_-97
*/ Z'Uc}M'U
publicinterface UserDAO extends BaseDAO { %"yy8~|
:t)<$dtf[
publicList getUserByName(String name)throws Nbyc,a[o
xZ=6
HibernateException; $u"*n\k>
^ "D
publicint getUserCount()throws HibernateException; ;\mTm;]G
a ]b%v9
publicList getUserByPage(Page page)throws w?JRY
mMt~4(5
HibernateException; ]=ubl!0=:
rl__3q
} Ung K9uB~
~;AJB
cXDG(.!n7B
K?J?]VCw
f.e4 C,
java代码: }57d3s
bVgmjt2&>
QKP@+E_U
/*Created on 2005-7-15*/ "e ;wN3/bF
package com.adt.dao.impl; !
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}L|cg2y
import java.util.List; 7g%.:H=
^U;r>[T9h
import org.flyware.util.page.Page; f53WDI6
nqv#?>Z^OT
import net.sf.hibernate.HibernateException; e0e3b]
import net.sf.hibernate.Query; CqAv^n7 }
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import com.adt.dao.UserDAO; 9{-
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/** zNh$d;(O$^
* @author Joa .dw;b~p
*/ [g Y.h/
public class UserDAOImpl extends BaseDAOHibernateImpl k62KZ5| D
@ak3ZNor
implements UserDAO { b!l/O2
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Jc9BZ`~i
/* (non-Javadoc) 3:B4;
* @see com.adt.dao.UserDAO#getUserByName VT:m!<^
b&g`AnYT
(java.lang.String) kN8?.V%Utw
*/ _ry7[/)
publicList getUserByName(String name)throws &60#y4
=N?K)QD`
HibernateException { ;n2b$MB?nM
String querySentence = "FROM user in class WoSJp5By$
VGL!)1b
com.adt.po.User WHERE user.name=:name"; l(A>Rw|
Query query = getSession().createQuery @FLa i
];U}'&
(querySentence); mA" 82"
query.setParameter("name", name); JANP_b:t
return query.list(); hcrx(oJ5
} w=}R'O;k
PvkHlb^x%
/* (non-Javadoc) Ks/Uyu. X
* @see com.adt.dao.UserDAO#getUserCount() *#&s+h,^
*/ xA#'%|"
publicint getUserCount()throws HibernateException {
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int count = 0; fs3jPHZJ#
String querySentence = "SELECT count(*) FROM r4wnfy
_VFL}<i
user in class com.adt.po.User"; Z#_ +yw
Query query = getSession().createQuery MU#$tXmnC
\+I+Lrj%
(querySentence); &h67LMD!
count = ((Integer)query.iterate().next ^hIKDc!.m
4SGF8y@WU
()).intValue(); t=6Wk4
return count; ZNjqH[
} f<K7m
j87IxB?o
/* (non-Javadoc) RXWS,rF
* @see com.adt.dao.UserDAO#getUserByPage oP`yBX
38 HnW
(org.flyware.util.page.Page) 6JZ$;x{j
*/ 6~y7A<[^
publicList getUserByPage(Page page)throws n<3*7/-
@K}8zMmW#
HibernateException { h"849c;C.
String querySentence = "FROM user in class ?D]qw4 J
+ug[TV
com.adt.po.User"; lV)SOs$
Query query = getSession().createQuery 0ofl,mXW
t^(#~hx
(querySentence); 1Yb9ILX[J
query.setFirstResult(page.getBeginIndex()) BdYl
sYp
.setMaxResults(page.getEveryPage()); u4,b%h.
return query.list(); \[ 5mBuk
} +/Vi"
[-*8S1
} B9Z=`c.T
ckg8x&Z
`ek On@T0
u*C"d1v=
VjhwafYC
至此,一个完整的分页程序完成。前台的只需要调用 |&xjuBC
{I~[a#^
userManager.listUser(page)即可得到一个Page对象和结果集对象 QnPgp(d<
@[] A&)B
的综合体,而传入的参数page对象则可以由前台传入,如果用 VN[i;4o:|
$v*0\O
webwork,甚至可以直接在配置文件中指定。 YTo^Q&
;rJ
下面给出一个webwork调用示例: WKB@9Vfju
java代码: /naGn@m5u
#Ies
yNKZ
9e xHR&>{
/*Created on 2005-6-17*/ i@|.1dWh
package com.adt.action.user; 0-{l4;o
G*$a81dAX
import java.util.List; VtJy0OGcRP
?=lnYD j
import org.apache.commons.logging.Log; ;N/=)m
import org.apache.commons.logging.LogFactory; !s:v UY58
import org.flyware.util.page.Page; {Q@pF
|}y6U< I
import com.adt.bo.Result; 5NECb4FG
import com.adt.service.UserService; oL69w1
import com.opensymphony.xwork.Action; bAl0z)p
GP/Gv
/** HxmCKW!
* @author Joa YvP u%=eF
*/ [
queXDn"m
publicclass ListUser implementsAction{ _Mis-K:]{?
B hnwb0b<
privatestaticfinal Log logger = LogFactory.getLog $3C$])k
UIl^s8/
(ListUser.class); F< #!83*%
D;l)&"|r?
private UserService userService; LN?b6s75U
al3[Ph5G
private Page page; nPj/C7j
LpJ_HU7@lk
privateList users; $*u{i4b
<Gr775"
/* }nW) +
* (non-Javadoc) ,UD,)ZPf[
* ecI[lB
* @see com.opensymphony.xwork.Action#execute() J&