Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _=XX~^I,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 5]Ajf;W\
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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 d l]#
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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 4_?7&G0(
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分页支持类: e&<yX
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java代码: Q9F)
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package com.javaeye.common.util; 3(E
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import java.util.List; p*QKK@C
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publicclass PaginationSupport { =3xE:
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publicfinalstaticint PAGESIZE = 30; =qVP] 9
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privateint pageSize = PAGESIZE; BHDML.r }M
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privateList items; 5N$E()m$
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privateint totalCount; s54nF\3V
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privateint[] indexes = newint[0]; 5f'DoT
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privateint startIndex = 0; "Y:/=
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public PaginationSupport(List items, int Pn.bVV:
d[gl]tj9
totalCount){ $"JpFT
setPageSize(PAGESIZE); 5/><$06rq
setTotalCount(totalCount); cV
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setItems(items); !\ND(
setStartIndex(0); |iYg >
} rt-\g1x
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public PaginationSupport(List items, int q(o/yx{bm
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totalCount, int startIndex){ 's?Ai2=#
setPageSize(PAGESIZE); Nt`b;X&
setTotalCount(totalCount); ;#+0L$<t
setItems(items); G#`\(NW
setStartIndex(startIndex); _cH@I?B
} b}9[s
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public PaginationSupport(List items, int \BV
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totalCount, int pageSize, int startIndex){ eitu!=u
setPageSize(pageSize); b8KsR=]4I
setTotalCount(totalCount); c{#yx_)V&
setItems(items); \0;(VLN'U
setStartIndex(startIndex); *O$CaAr\s
} f|EUqu%E
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publicList getItems(){ ;^u*hZN[Up
return items; q z&+=d@
} u+9<&)X0
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publicvoid setItems(List items){ K/_9f'^
this.items = items; v5ur&egVs
} `iKj
* A|-KKo\
publicint getPageSize(){ W`rNBfG>
return pageSize; #G]! %
} FyL_xu\e
e;YW6}'}
publicvoid setPageSize(int pageSize){ mABe'"8
this.pageSize = pageSize; _W!p8cB
} \uOdALZ
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publicint getTotalCount(){ -<_$m6x"A
return totalCount; U]~^Z R
} @DAF 6ygs
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publicvoid setTotalCount(int totalCount){ 0[A9b,MMVO
if(totalCount > 0){ (P|~>k
this.totalCount = totalCount; V}w;Y?]J
int count = totalCount / h~Q)Uy5N(D
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pageSize; &O\(;mFc
if(totalCount % pageSize > 0) +V862R4,o
count++; &fP XU*l4
indexes = newint[count]; &:B<Q$g#
for(int i = 0; i < count; i++){ ._:nw=Y0<}
indexes = pageSize * 6&U+6gb
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} m#H3:-h,
}else{ o`,Qku k
this.totalCount = 0; RuW!*LI
} 'Yy&G\S
} _A_ A$N~9
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publicint[] getIndexes(){ }A$WO{2
return indexes; #b0{#^S:
} $WQq?1.9
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publicvoid setIndexes(int[] indexes){ N@o?b
this.indexes = indexes; RH;:9_*F
} eDO!^.<5
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publicint getStartIndex(){ w]j+9-._
return startIndex; 2h30\/xkU
} Pj#'}ru!
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publicvoid setStartIndex(int startIndex){ qUF'{K
if(totalCount <= 0) v*hRz;
this.startIndex = 0; RWq{Ff}Hk
elseif(startIndex >= totalCount) Wa/g`}
this.startIndex = indexes ^W83ByP
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[indexes.length - 1]; "L"150Ih
elseif(startIndex < 0) =H7xD"'%R
this.startIndex = 0; `rY2up#%
else{ )n7l'}o?+
this.startIndex = indexes V)o,1
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[startIndex / pageSize]; 2+8#H.
} y9Y1PH7G
} ]bCq=6ZKR
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publicint getNextIndex(){ kW=z+
int nextIndex = getStartIndex() + P%pp
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pageSize; }7<5hn E
if(nextIndex >= totalCount) Zwt; d5U
return getStartIndex(); \~rlgxd
else "+ "{+k5t
return nextIndex; "GT4s?6O
} @!=\R^#p
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publicint getPreviousIndex(){ {Ng oYl
int previousIndex = getStartIndex() - JM$.O;y
-
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pageSize; "LhUxnll
if(previousIndex < 0) .o{0+fC#
return0; 1tzV8(7
else pI`?(5iK6|
return previousIndex; ,M !tm7
} <M?:
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} -OZ 5vH0
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抽象业务类 _hf4A8ak
java代码: Kz8:UG(
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/** Ths_CKwgWY
* Created on 2005-7-12 / RZR}
*/ fr6^nDY
package com.javaeye.common.business; _Yb_D/
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import java.io.Serializable; iItcN;;7
import java.util.List; q*jNH\|
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import org.hibernate.Criteria; YEu1#N
import org.hibernate.HibernateException; ewNz%_2
import org.hibernate.Session; 8cx=#Me
import org.hibernate.criterion.DetachedCriteria;
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import org.hibernate.criterion.Projections; ?VU(Pq*`
import u#7+U\
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org.springframework.orm.hibernate3.HibernateCallback; #h!*dj"
import %b.UPS@I
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org.springframework.orm.hibernate3.support.HibernateDaoS wu<])&F
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upport; [36,eK
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import com.javaeye.common.util.PaginationSupport; ExSe=4q#
/(I*,.d
public abstract class AbstractManager extends C.:=lo B
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HibernateDaoSupport { !;@_VWR
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privateboolean cacheQueries = false; O[17";P
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privateString queryCacheRegion; h 6G/O`:
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publicvoid setCacheQueries(boolean ? Q@kg
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cacheQueries){ G |*(8r()
this.cacheQueries = cacheQueries; WlB'YL-`g
} %ugHhS!
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publicvoid setQueryCacheRegion(String ^da44Qqu
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queryCacheRegion){ 5\mTr)\R
this.queryCacheRegion = eC
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queryCacheRegion; Hi!Jj
} "\"DCDKmG
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publicvoid save(finalObject entity){ ;:S&F
getHibernateTemplate().save(entity); e[u?_h
} {",MCu_V
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publicvoid persist(finalObject entity){ GJi~y
getHibernateTemplate().save(entity); 05Fz@31~
} 148V2H)
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publicvoid update(finalObject entity){ QZAB=rR
getHibernateTemplate().update(entity); 9 A,Z|q/z5
} dBsX*}C
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publicvoid delete(finalObject entity){ 7T``-:`[
getHibernateTemplate().delete(entity); @r(Z%j7
} I-D^>\k+
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publicObject load(finalClass entity, i>L+gLW
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finalSerializable id){ M`,~ mU
return getHibernateTemplate().load MfF~8
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(entity, id); _i_Q?w`
} ->z54 T
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publicObject get(finalClass entity, )"(] Lf's
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finalSerializable id){ Jo(`zuLJ
return getHibernateTemplate().get 0X8t>#uF
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(entity, id); 2A`A\19t
} &adI (s~
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publicList findAll(finalClass entity){ uf<@ruN
return getHibernateTemplate().find("from MvLs%GE%
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" + entity.getName()); "eWk#/
} =.<@`1
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publicList findByNamedQuery(finalString 5V[oE\B
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namedQuery){ WFR?fDtE
return getHibernateTemplate ^VW
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().findByNamedQuery(namedQuery); TlL^7f}
} 'AGto'Yy;
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publicList findByNamedQuery(finalString query, ,)+o
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finalObject parameter){ A61^[Y,dX_
return getHibernateTemplate Mj-vgn&/
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().findByNamedQuery(query, parameter); vE6mOM!_L
} ~0$NJrUy
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publicList findByNamedQuery(finalString query, 5*PYT=p}
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finalObject[] parameters){ |Z\R*b"
return getHibernateTemplate N- e$^pST
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().findByNamedQuery(query, parameters); -50HB`t
} *D4hq=
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publicList find(finalString query){ 0`.^MC?
return getHibernateTemplate().find ^m#-9- `
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(query); 'K@|3R
} g
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publicList find(finalString query, finalObject /-zXM;h
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parameter){ ]3ONFa
return getHibernateTemplate().find }7fZ[J3
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(query, parameter); 7*j
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} eD$M<Eu
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public PaginationSupport findPageByCriteria ^Jb
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(final DetachedCriteria detachedCriteria){ Er/bO
return findPageByCriteria Ze<K=Q%(i
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); kK8itO
} d\e7,"L*Q
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public PaginationSupport findPageByCriteria $,I q;*7N
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(final DetachedCriteria detachedCriteria, finalint MRU7W4W-~/
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startIndex){ ,Vd\m"K{
return findPageByCriteria u4z&!MT}
fA'qd.{f^
(detachedCriteria, PaginationSupport.PAGESIZE, ly% F."v
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startIndex); !8 &=y
} T5urZq*R
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public PaginationSupport findPageByCriteria 0CSv10Tg
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(final DetachedCriteria detachedCriteria, finalint 'c\iK=fl
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pageSize, ntNI]~z&
finalint startIndex){ R1&unm0
return(PaginationSupport) =to=8H-
!=;XBd-
getHibernateTemplate().execute(new HibernateCallback(){ 'mI'dG
publicObject doInHibernate .xf<=ep
[c_|ob]
(Session session)throws HibernateException { E{6~oZ#L
Criteria criteria = Q1V9PRZX
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detachedCriteria.getExecutableCriteria(session); J0zn-
int totalCount = +C7 ~b~ %
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((Integer) criteria.setProjection(Projections.rowCount Zmbfq8K
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()).uniqueResult()).intValue(); ^Rm
criteria.setProjection No2b"G@
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(null); 6c0>gUQx-
List items = /0\
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criteria.setFirstResult(startIndex).setMaxResults ,C3,TkA]
}kg ye2[
(pageSize).list(); u!1{Vt87
PaginationSupport ps = M$f7sx
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new PaginationSupport(items, totalCount, pageSize, 8* Jw0mSw
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startIndex); HF|oBX$_
return ps; w+1Gs
;
} @p\}p Y$T
}, true); );-~j
} m%?V7-9!k
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public List findAllByCriteria(final X.`~>`8
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DetachedCriteria detachedCriteria){ x@8a''
return(List) getHibernateTemplate KZ~*Nz+H2
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().execute(new HibernateCallback(){ 6q
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publicObject doInHibernate `6+"Z=:
#c^^=Z
(Session session)throws HibernateException { +iOKb c'
Criteria criteria = 9@+5LZR
8,dBl!G=
detachedCriteria.getExecutableCriteria(session); O12eH
return criteria.list(); g+X}c/".
} k4 F"'N
}, true); Cu6%h>@K$
} $1SUU F\.
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public int getCountByCriteria(final "Ks,kSEzu
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DetachedCriteria detachedCriteria){ {k rswh3
Integer count = (Integer) ;#Q%j%J
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getHibernateTemplate().execute(new HibernateCallback(){ $.]l!cmi%Q
publicObject doInHibernate 86nN"!{l:
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(Session session)throws HibernateException { +^;JS3p@\
Criteria criteria = <$JaWL
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detachedCriteria.getExecutableCriteria(session); +>JjvYx}\
return m.,U:>
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criteria.setProjection(Projections.rowCount fFQ|T:vm
[`
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()).uniqueResult(); #:SNHM^><
} 4`,j =3
}, true); Dc)dE2
return count.intValue(); s.8{5jVG
} :6%Z]tt
} B7imV@<
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用户在web层构造查询条件detachedCriteria,和可选的 5atYOep
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 NIw\}[-Z0E
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PaginationSupport的实例ps。 B$Kn1 k
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ps.getItems()得到已分页好的结果集 /&4U6a
ps.getIndexes()得到分页索引的数组 ^Ox3XC
ps.getTotalCount()得到总结果数 %iw3oh&Fkm
ps.getStartIndex()当前分页索引 ZK)%l~J
ps.getNextIndex()下一页索引 fum0>tff
ps.getPreviousIndex()上一页索引 ]LM-@G+Jz
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 0#MqD[U(
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ZzX~&95G
'PP#^aI,
一下代码重构了。 0P]E6hWgg
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我把原本我的做法也提供出来供大家讨论吧: ,\@O(;
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首先,为了实现分页查询,我封装了一个Page类: `HBf&Z
java代码: %$DI^yS
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/*Created on 2005-4-14*/ 28=O03q
package org.flyware.util.page; uDZT_c'Y
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/** C7O6qpO
* @author Joa p*P)KP
* 42qYg(tZ
*/ yR\btx|e5~
publicclass Page { 71{p+3Z&
Z@$8I{}G
/** imply if the page has previous page */ B9J&=6`)
privateboolean hasPrePage; _x5 3g
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/** imply if the page has next page */ /QJ?bD#a
privateboolean hasNextPage; "T- `$'9
#KiRfx4G
/** the number of every page */ Qg<(u?7N
privateint everyPage; 9*(aUz9j
\(vY%DL1:
/** the total page number */ icgSe:Ci
privateint totalPage; Vkc#7W(
Kc^;vT>3
/** the number of current page */ ih;]nJ]+-
privateint currentPage;
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/** the begin index of the records by the current `{xNXH]@
9uQ 4u/F
query */ |x-S&-
privateint beginIndex; e[#j.|m
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/** The default constructor */ oTuOw|[
public Page(){ GHeVp/u
h^o{@/2
} A`}rqhU.{-
_n` a`2C|m
/** construct the page by everyPage AlIpsJ[UU
* @param everyPage o$Z6zm xO
* */ [Yc G(^^
public Page(int everyPage){ 7fba-7-P
this.everyPage = everyPage; CtS l
} Pw61_ZZ4B\
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/** The whole constructor */ 9BuSN*4
public Page(boolean hasPrePage, boolean hasNextPage, *9{Z$IA9w
uPl\I6k
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int everyPage, int totalPage, fu]s/'8B
int currentPage, int beginIndex){ iB& 4>+N+
this.hasPrePage = hasPrePage; 9B7^lR
this.hasNextPage = hasNextPage; )(384@'"u
this.everyPage = everyPage; AQ[GO6$,%H
this.totalPage = totalPage; aiu5}%U
this.currentPage = currentPage; 6'Worj
this.beginIndex = beginIndex; 4Q6mo/=H
} pxh"B\"4*
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/** J\M>33zu
* @return <
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* Returns the beginIndex. "*srx]
*/ 65aK2MS@
publicint getBeginIndex(){ uW}s)j.
return beginIndex; G%W8S
\
} ^8AXxE
428>BQA
/** 8Y7Q+p|O
* @param beginIndex @8ppEFw
* The beginIndex to set. &RnTzqv
*/ u*ObwcI/Bn
publicvoid setBeginIndex(int beginIndex){ GfmI<{da
this.beginIndex = beginIndex; PC-"gi=h
} +2&@x=xy
a+Kj1ix
/** N%*5 T[.
* @return j+uLV{~g6
* Returns the currentPage. f m)pulz
*/ 'g
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publicint getCurrentPage(){ A"G
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return currentPage; ^Uf]Q$uCjE
} G'ei/Me6{
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/** ov_j4j>6P
* @param currentPage [8=vv7wS
* The currentPage to set. )E-inHD /
*/ Ne[7gxpu
publicvoid setCurrentPage(int currentPage){ |6K+E6H
this.currentPage = currentPage; noml8o
} {^7Hgg
,>0* @2
/** 7G}2,ueI
* @return 'kL#]
* Returns the everyPage. $JMXV
*/ !y@NAa0
publicint getEveryPage(){ %}Ss,XJ
return everyPage; ?&63#B,iZ
} !O:y@
Of[XKFn_
/** _lGdUt 2
* @param everyPage iB%gPoDCL@
* The everyPage to set. LE9(fe) fe
*/ MbZJ;,e?
publicvoid setEveryPage(int everyPage){ 7b;I+q
this.everyPage = everyPage; +wN^c#~7
} j}JrE,|
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/** YkniiB[/
* @return ]+XYEv
* Returns the hasNextPage. Z{ X|6.
*/ %S*{9hm/
publicboolean getHasNextPage(){ aTqd@},?
return hasNextPage; G
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} )4<__|52"1
$Q96,rb}k;
/** beRVD>T
* @param hasNextPage /H(?
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* The hasNextPage to set. si`A:14R
*/ Crho=RJPR
publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; zF8dKFE~
} (e!0]Io@
mpI5J'>]
/** ^S UPi
* @return b&~4t/Vq
* Returns the hasPrePage. ]b7zJUz
*/ 6K-_pg]
publicboolean getHasPrePage(){ OWjk=u2Lz
return hasPrePage; 8S mCpg
} / ';0H_
juka0/
/** pQ=>.JU
* @param hasPrePage Y;@>b{s
* The hasPrePage to set. 1zm ulj%&
*/ j9?}j#@
publicvoid setHasPrePage(boolean hasPrePage){ EQb7-vhg
this.hasPrePage = hasPrePage; 3DiLk=\~
} \W1,F6&j
R7$:@<:g
/** 9[b<5Llt
* @return Returns the totalPage. Q[vJqkgT
* JJ}0gZ
*/ ?s\:hNNY
publicint getTotalPage(){ 2N~Fg^xB
return totalPage; m?pstuUK(
} "HElB9
lef2 X1w}!
/** (l-tvk4Ln
* @param totalPage \K@'Z
* The totalPage to set. Cjqklb/
*/ iop2L51eJ
publicvoid setTotalPage(int totalPage){ C([phT;
this.totalPage = totalPage; 3L833zL
} e+$p9k~
+$C4\$t
} *c~T@m~DR
#!aN{nK0
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x(hE3S#+
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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 u<3HQ.:;
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个PageUtil,负责对Page对象进行构造: ROg(U8
N
java代码: ?u/@PR\D
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_hRcc"MS`
/*Created on 2005-4-14*/ iYDEI e
package org.flyware.util.page; SSz~YR^}Sr
8P^ITL z%
import org.apache.commons.logging.Log; lG4H:[5V
import org.apache.commons.logging.LogFactory; U}6.h&$
4{hps.$?~
/** ;3d"wW]}7K
* @author Joa a:"Uh**
* !lf|7
*/ 4]h
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publicclass PageUtil { D2](da:]8)
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privatestaticfinal Log logger = LogFactory.getLog @6{~05.p
D B-l$rj
(PageUtil.class); ue4Vcf
-R57@D>j\
/** Y%PwktQm
* Use the origin page to create a new page a=DcZ_M
* @param page e?7&M
* @param totalRecords f0X_fm_q
* @return NWM8[dI
*/ 3pv4B:0
publicstatic Page createPage(Page page, int ` D= S{
99:C"`E{
totalRecords){ @!`Xl*l
return createPage(page.getEveryPage(), }dp=?AFg
#9X70|f
page.getCurrentPage(), totalRecords); /LO-HnJ
} o
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/** 3):A
* the basic page utils not including exception y^%n'h{
?YZ- P{rTS
handler ``ou/Z
* @param everyPage JBJhG<J
* @param currentPage _59huC.
* @param totalRecords g=QDu7Ux
* @return page
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*/ UD8op]>L
publicstatic Page createPage(int everyPage, int U@-^C"R
GH+r?2<
currentPage, int totalRecords){ fjU8gV
everyPage = getEveryPage(everyPage);
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currentPage = getCurrentPage(currentPage); 9\/xOwR
int beginIndex = getBeginIndex(everyPage, NMa}
<
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currentPage); ~C>?W[Y
int totalPage = getTotalPage(everyPage, F )W:
R~)\3] "2m
totalRecords); kg'o&^/=
boolean hasNextPage = hasNextPage(currentPage, KU8Jbl*
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y>
totalPage); =>M^02"
boolean hasPrePage = hasPrePage(currentPage); 5*1D$mxD"
;
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returnnew Page(hasPrePage, hasNextPage, ~g5[$r-u-u
everyPage, totalPage, M+w=O!dq
currentPage, P/Q!<I
LN@F+CyDc
beginIndex);
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} C!fMW+C@
H[S%J3JI
privatestaticint getEveryPage(int everyPage){ paKSr|O
return everyPage == 0 ? 10 : everyPage; #MRMNL@
} [uI|DUlI6o
<})2#sZO!
privatestaticint getCurrentPage(int currentPage){ a=hxJ1O
return currentPage == 0 ? 1 : currentPage; QNpqdwu%h
} %?p1d!
no<
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privatestaticint getBeginIndex(int everyPage, int ?XA2&
DV<` K$ET
currentPage){ XpBj%e:
return(currentPage - 1) * everyPage; I?ae\X@M
} tE]= cTSV
J"=vE=
privatestaticint getTotalPage(int everyPage, int _OuWB"
Kfh|
totalRecords){ :'~Y
int totalPage = 0; f;1K5Y
@I_8T$N=
if(totalRecords % everyPage == 0) =8; {\
totalPage = totalRecords / everyPage; 9983aFam
else gx\&_)w N
totalPage = totalRecords / everyPage + 1 ; Il=
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7z!tKs"TMT
return totalPage; wnM9('\
} A-T]9f9
V3c l~
privatestaticboolean hasPrePage(int currentPage){ }>VG~u8
return currentPage == 1 ? false : true; ,PWgH$+
} v"OY 1<8
9Hc$G{[a
privatestaticboolean hasNextPage(int currentPage, PDrZY.-
1e&QSzL
int totalPage){ ;uwRyd
return currentPage == totalPage || totalPage == nij!1z|M
X_$Cb<e
0 ? false : true; $CY't'6Hn
} ~:3QBMk::
,]+z)
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} 20Z8HwQi
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K)\M5id]
$D}{]MN.
=u+d_'P7-R
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@<CsgKB-
7D!u1?]d{
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 4)U.5FBk
)
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做法如下: pb$~b\s]=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 v7DE
@O[}QB?/fi
的信息,和一个结果集List: Dg}
Ka7H
java代码: nSkPM5\TI
C@bm
/6h(6 *JI
/*Created on 2005-6-13*/ Xt#4/>dlR
package com.adt.bo; ~R&;v3
t| 'N+-T3
import java.util.List; {WPobP"
opJMS6%r
import org.flyware.util.page.Page; QC X8IIHG
kjtjw1\o
/** "sl1vzRN
* @author Joa 9$|Gfyv
*/ cg*)0U-_(
publicclass Result { /Ne<V2AX
NN1$'"@NL
private Page page; ^pe{b9c
+{L<? "
private List content; YBP:q2H
K!] 1oy'V
/** M>>qn_yq4
* The default constructor ,i,q!M{-
*/ ,$
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public Result(){ aN $}?
super(); YI.w-K\
} i7utKj*57
bLd#xXl
/** X0M1(BJgGo
* The constructor using fields SJ};TEA
* K
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* @param page ^+m+zd_
* @param content i6 (a@KRY
*/ j~e;DO
public Result(Page page, List content){ ]/B$br'O{?
this.page = page; ~DsECnD
this.content = content; V]vc(rH
} F`9ZH.
jvV9eA:zl
/** zKsz*xv6b
* @return Returns the content. k!KDWb
*/ -~QHqU.
publicList getContent(){ 8-Hsgf.*
return content; )"m!YuS Y
} l$jxLZ
m~D&gGFt
/** nYt/U\n!
* @return Returns the page. $8'O
*/ zBP>jM(8
public Page getPage(){ "luR9l,RRE
return page; QlHd,w
} 6"D/xV3Z
Zb134b'
/** UD)e:G[Gat
* @param content j$TwL;
* The content to set. ]d]JXt?)i
*/ UEzb^(8>
public void setContent(List content){ ,E$@=1)
this.content = content; _C+b]r/E
} XbZ*&
vYU;_R
/** =Mb1o[
* @param page j$7Xs"
* The page to set. xGG,2W+z
*/ %Jf<l&K.`
publicvoid setPage(Page page){ brZ sAQ+k
this.page = page; $L2%u8}8:
} Z-B%'/.
} v*qQ? S
q;:6_Qr
B:\Uw|Mf
/2RajsK
)Y8",Ig
2. 编写业务逻辑接口,并实现它(UserManager, ZJjTzEV%^B
Na\WZSu'"
UserManagerImpl) atW'
java代码: Go&D[#
~-83Q5/[
//&j<vus
/*Created on 2005-7-15*/ SgEBh
package com.adt.service; tL+OCLF;
: ~ A%#
import net.sf.hibernate.HibernateException; w?,M}=vg
Y=T'WNaL)0
import org.flyware.util.page.Page; ZK'-U,Y.H7
a@pz*e
import com.adt.bo.Result; )kJH5/
0'r%,0
/** A~dQ\M
* @author Joa L}yyaM)
*/ ]O:N-Y
publicinterface UserManager { 8V-\e?&^
34QfgMyH
public Result listUser(Page page)throws }elH75[64
G8I Y#
HibernateException; T'fcc6D5p
Z.wA@ ~e
} 2F8|I7R
((rv]f{
QI_59f>
?_`0G/xl
'ho{eR@d
java代码: 0"g@!gSrQ
|8)Xc=Hz
c
{I"R8
/*Created on 2005-7-15*/ jvzBh-!
package com.adt.service.impl; M_``'gw
nVD Xj
import java.util.List; y@wF_WX2
jLcHY-P0V
import net.sf.hibernate.HibernateException; QT#6'>&7-b
:o"8MZp
import org.flyware.util.page.Page; yW.COWL=)
import org.flyware.util.page.PageUtil; 1'G8o=~
Vj;
vo`T
import com.adt.bo.Result; Ewo*yY>
import com.adt.dao.UserDAO; MjaUdfx
import com.adt.exception.ObjectNotFoundException; Napf"Av
import com.adt.service.UserManager; 0p fnV%
sygH1|f
/** gUB{Bh($Y
* @author Joa THhy ~wC".
*/ z#<P}}
publicclass UserManagerImpl implements UserManager { AH.9A_dG
wUi(3g|A
private UserDAO userDAO; -cNx1et
nj\_lL+
/** he)ulB
* @param userDAO The userDAO to set. j.3o W
*/ ,2 WH/"
publicvoid setUserDAO(UserDAO userDAO){ m%QqmTH
this.userDAO = userDAO; Vos?PqUi 4
} ew#T8F[
r@T| e
/* (non-Javadoc) EaS~`
* @see com.adt.service.UserManager#listUser S=gW(c2'
Z{{t^+XG
(org.flyware.util.page.Page) `HUf v@5
*/ !v!N>f4S$
public Result listUser(Page page)throws .#^0pv!
xKp0r1}
HibernateException, ObjectNotFoundException { |0{ i9.=
int totalRecords = userDAO.getUserCount(); -Gsl[Rc0H;
if(totalRecords == 0) j"<Y!Y3
throw new ObjectNotFoundException NcL
=zo<
lVeH+"M?
("userNotExist"); a]1i/3/
page = PageUtil.createPage(page, totalRecords); =LZ>su
List users = userDAO.getUserByPage(page); ]5|z3<K^
returnnew Result(page, users); Goj4`Hc
} Sb^
b)q"
A|<;
} |#TXE|#ux
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Vdvx"s[`m
w)S; J,Hv
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 &]nd!N
Um
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询,接下来编写UserDAO的代码: KR3-Hb4
3. UserDAO 和 UserDAOImpl: :'w?ye[e
java代码: bNvAyKc-
B-Y+F
Mn"/#tXL-
/*Created on 2005-7-15*/ #t5juX9Ho9
package com.adt.dao; b*9e1/]
v+tO$QZ`
import java.util.List; 8Nvr93T,
N^@
\tg=
import org.flyware.util.page.Page; Tcs3>lJ}
v_-ls"l
import net.sf.hibernate.HibernateException; ?1m ,SK
/v&`!nKu
/** Am7| /
* @author Joa i$#,XFFp~
*/ ;a{rWz1Wm
publicinterface UserDAO extends BaseDAO { EHWv3sR-
p#b{xK
publicList getUserByName(String name)throws I2*oTUSik
|p'i,.(c_W
HibernateException; K%<GU1]-]
/s-d?
publicint getUserCount()throws HibernateException; luF#OP C
9`&77+|;e
publicList getUserByPage(Page page)throws t/Z!O
z6ZE
Orc>.~+f%A
HibernateException;
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A}eOR=E
} W}k[slqZA
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Fhi5LhWe+.
~D!ESe*=
M;@Ex`+?i
java代码: y(a}IM3~
[5LMt*Y
aZ/yCS7
/*Created on 2005-7-15*/ ^HoJ.oC/
package com.adt.dao.impl; 5|m9:Hv[#
Jh(mbD
import java.util.List; |bvGYsn_#=
/^QFqM;
import org.flyware.util.page.Page; T=yCN#cqQ`
i\Q":4
import net.sf.hibernate.HibernateException; T;%+ ]:w<
import net.sf.hibernate.Query; %rFllb7
8"pA9Mr
import com.adt.dao.UserDAO; "{6KZ! +0
Wlxk
/** 5YLho2h38!
* @author Joa DUPmq!A
*/ `~KAk
public class UserDAOImpl extends BaseDAOHibernateImpl JSUzEAKe
a~F u
implements UserDAO { fcn_<Yh0W
TQ2i{e
/* (non-Javadoc) $WM8tF?H
* @see com.adt.dao.UserDAO#getUserByName YL!oF^XO
*q[^Q'jnN
(java.lang.String) Y/!0Q6<[2Y
*/ '&{(:,!B
publicList getUserByName(String name)throws
z8tt+AU
wtUG^hV #_
HibernateException { QJ6f
EV$~
String querySentence = "FROM user in class _BCT.ual
*ig5Q(b*N
com.adt.po.User WHERE user.name=:name"; ]:Wb1
Query query = getSession().createQuery R=QM;
"vvFq ,c
(querySentence); s~#?9vW
query.setParameter("name", name); >d)|r
return query.list(); i|[S5QXCh
} fV v$K&
aeQ{_SK
/* (non-Javadoc) {bxhH)a'
* @see com.adt.dao.UserDAO#getUserCount() UFJEs[?+Te
*/ d OzO/w&
publicint getUserCount()throws HibernateException { ],!pp3U
int count = 0; 8Q+TE;
String querySentence = "SELECT count(*) FROM ~'|&{-<
UfO'.8*v
user in class com.adt.po.User"; FJ nG<5Rh
Query query = getSession().createQuery MEDskvBG
*E$H;wKs8
(querySentence); @$_rEdwi
count = ((Integer)query.iterate().next Y}*Ctdrl
s')!<E+z\t
()).intValue(); \y<+Fac1S
return count; #0xm3rFy4
} w 2s,
jWz|K
/* (non-Javadoc) Ab/v_mA;
* @see com.adt.dao.UserDAO#getUserByPage C} |O#"t^\
$d5&~I
(org.flyware.util.page.Page) ]q@rGD85K
*/ 7?)m(CFy
publicList getUserByPage(Page page)throws aj%
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'[0
3L9
HibernateException { A/r;;S)%2
String querySentence = "FROM user in class F&-5&'6G+
dVK@Fgo
com.adt.po.User"; zX006{vig
Query query = getSession().createQuery Ebmqq#SHjX
!<JG&9ODP
(querySentence); ^$3w&$K*
query.setFirstResult(page.getBeginIndex()) a^(S!I
.setMaxResults(page.getEveryPage()); <$Xn:B<H
return query.list(); <%T%NjNPQ
} tauP1&%oH{
:6qUSE
} `=WzG"
^2P;CAjj-
k)o7COx
~0:$G?fz
*NKC\aV`0
至此,一个完整的分页程序完成。前台的只需要调用 Zm?G'06
JT}dor
userManager.listUser(page)即可得到一个Page对象和结果集对象 OqUE4.vIP
6oe$)iV
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~W5>;6f\
m|g$'vjk
webwork,甚至可以直接在配置文件中指定。 ,5%aP%
&ij^FAM
下面给出一个webwork调用示例: h=mI{w*
java代码: LKoM\g(
K'ed5J
u^;sx/
/*Created on 2005-6-17*/ p2M?pV
package com.adt.action.user; ?3e!A9x
`3H?*\<(
import java.util.List; *&~sr
as\)S?0`.
import org.apache.commons.logging.Log; 9'1;-^U1
import org.apache.commons.logging.LogFactory; 4
g/<).1<b
import org.flyware.util.page.Page; bDcWb2lqs
j8F~j?%!
import com.adt.bo.Result; u/K)y:ZZ
import com.adt.service.UserService; BBZ)H6TzL
import com.opensymphony.xwork.Action; U{.+*e18
'R-JQE-]
/** #m[w=Pu}
* @author Joa vs)HbQ
*/ QB
oZCLv
publicclass ListUser implementsAction{ d60Fi#3d
%K/G+
privatestaticfinal Log logger = LogFactory.getLog bE%mgaOh
X.W#=$;$:
(ListUser.class); V9);kD
"J0Oa?
private UserService userService; B_6v'=7]
0*'`%W+5
private Page page; KD<; ?oN<O
)PanJHtU
privateList users; '+GVozc6c"
<y b=!
/* Bwi[qw
* (non-Javadoc) (urfaZ;@+
* Vtc)/OH
* @see com.opensymphony.xwork.Action#execute() UC<[z#]\;
*/ [M zc^I&
publicString execute()throwsException{ 9x
6ca
Result result = userService.listUser(page); Xk7$?8r4&
page = result.getPage(); 4YB7og%P
users = result.getContent(); 2TevdyI
return SUCCESS; kcZ;SYosj
} ^FyvaO
R*c0NJF
/** OD2ai]!v+
* @return Returns the page. :pV("tHE
*/ PK|`}z9
public Page getPage(){ J.+?*hcw
return page; |4 d{X@`&
} Ozh^Q$>u
LMhY"/hAXa
/** P*qNRP%
* @return Returns the users. F.* snF
*/ (J) Rs`_
publicList getUsers(){ e&]`X HC9
return users; W:N"O\`{m
} lCs8`bYU
~Hs]} Xo
/** w[$Wpae
* @param page ![."xHVeL
* The page to set. y^+[eT&