Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6kHuKxY,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 >D_!d@Z
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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 PYyT#AcW2
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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 -=GmI1:=$4
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分页支持类: i|!W;2KL5
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java代码: d@ef+-
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package com.javaeye.common.util; oT i$@q
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import java.util.List; ^?S lM
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publicclass PaginationSupport { V|)nUsU
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publicfinalstaticint PAGESIZE = 30; #B5-3CwB
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privateint pageSize = PAGESIZE; I]Ws
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privateList items; G8lTIs4u;
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privateint totalCount; :'Tq5kE
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privateint[] indexes = newint[0]; 5`)[FCQ
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privateint startIndex = 0; 8TCbEPS@Q
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public PaginationSupport(List items, int 7T?T0x3>
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totalCount){ >:|jds#
setPageSize(PAGESIZE); }*c[}VLN
setTotalCount(totalCount); ne# %Gr
setItems(items); Erm]uI9`
setStartIndex(0); 2#@-t{\3-p
} 3j\Py'};
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public PaginationSupport(List items, int Dv}VmC""
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totalCount, int startIndex){ Q&vU|y
setPageSize(PAGESIZE); 6\RZ[gA?
setTotalCount(totalCount); w_*$wVl
setItems(items); &{S@v9~IT
setStartIndex(startIndex); b
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} ,"Nb;Yhg
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public PaginationSupport(List items, int
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totalCount, int pageSize, int startIndex){ t:%u4\nZ;
setPageSize(pageSize); dC?l%,W
setTotalCount(totalCount); 9PG3cCr?
setItems(items); (t"e#b(:
setStartIndex(startIndex); f<vZ4 IU
} +oiuulA
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publicList getItems(){ Lv@'v4.({
return items; {;3a^K
} ; Z2
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publicvoid setItems(List items){ ,EH^3ODD
this.items = items; /U=?D(>x
} */j[n$K>~`
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publicint getPageSize(){ 5
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return pageSize; @!B%ynrG
} iz2;xa*
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publicvoid setPageSize(int pageSize){ v
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this.pageSize = pageSize; \xX'SB#.l
} K}tC8D
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publicint getTotalCount(){ jBJ|%KM
return totalCount; s}?QA cC
} 8[x{]l[
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publicvoid setTotalCount(int totalCount){ v4r%'bA
if(totalCount > 0){ ms#|Yl1/|
this.totalCount = totalCount; i*e'eZ;)
int count = totalCount / a>#]d
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pageSize; u(g9-O
if(totalCount % pageSize > 0) EO"G(v
count++; V BjA$.
indexes = newint[count]; 4B@Ir)^(*
for(int i = 0; i < count; i++){ 5$c*r$t_RK
indexes = pageSize * ]f*.C9Y
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} gZ6tbp,X
}else{ p*~b5'+ C+
this.totalCount = 0; y~<_ux,
} oEsqLh9a|
} GE}>{x=^x
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publicint[] getIndexes(){ 3PEW0b*]Pf
return indexes; "BvDLe':
} 5c1{[
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publicvoid setIndexes(int[] indexes){ trlZ
this.indexes = indexes; ML7qrc;Rx
} d8VFa'|
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publicint getStartIndex(){ ~/;shs<9EM
return startIndex; V(F1i%9l g
} #./8inbG
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publicvoid setStartIndex(int startIndex){ 1
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if(totalCount <= 0) Y"E*#1/
this.startIndex = 0; ,ZvlKN
elseif(startIndex >= totalCount) _nec6=S6(
this.startIndex = indexes
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[indexes.length - 1]; ]
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elseif(startIndex < 0) =]P|!$!}0
this.startIndex = 0; qKNHhXi
else{ S=3 H.D!f
this.startIndex = indexes ,m;G:3}48
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[startIndex / pageSize]; 6QNO#!;
} %=5 m!"F
} #<yKG \X?
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publicint getNextIndex(){ 1V;,ZGI*
int nextIndex = getStartIndex() + ]9~6lx3/
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pageSize; Y{2L[5_1
if(nextIndex >= totalCount) PB!*&T'!
return getStartIndex(); .gA4gI1kH
else 7
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return nextIndex; }c'T]h\S
} qIk(ei
iH)-8Q
publicint getPreviousIndex(){ / a$B8,
int previousIndex = getStartIndex() - qoOq47F
d2*uY.,
pageSize; >C/O >g
if(previousIndex < 0) q[%SF=~<k{
return0; $i$Z+-W4'
else nh>lDfJV<
return previousIndex; )0{ZZ-beG
} y@\J7 h:
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} 94L>%{59
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抽象业务类 og|~:>FmJo
java代码: Kj*$'('
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/** D*!9K8<o
* Created on 2005-7-12 J;Veza
*/ W4:#=.m
package com.javaeye.common.business; !p(N
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import java.io.Serializable; iTJE:[W"y
import java.util.List; vSGvv43G
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import org.hibernate.Criteria; `D0Hu!;
import org.hibernate.HibernateException; N6!$V7oT
import org.hibernate.Session; }RZN3U=
import org.hibernate.criterion.DetachedCriteria; "SU
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import org.hibernate.criterion.Projections; W_h!Puj_
import VHx:3G
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org.springframework.orm.hibernate3.HibernateCallback; >?GCH(eW%
import io*iA<@Gx
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org.springframework.orm.hibernate3.support.HibernateDaoS 1D)=q^\I
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upport; '<&rMn
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import com.javaeye.common.util.PaginationSupport; WS1#i\0
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public abstract class AbstractManager extends 2g%p9-MO]I
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HibernateDaoSupport { "%K[kA6
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privateboolean cacheQueries = false; *hkNJ
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privateString queryCacheRegion; Wh1'?#
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publicvoid setCacheQueries(boolean 3zo:)N \K
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cacheQueries){ | gP%8nh'C
this.cacheQueries = cacheQueries; +%LR1+/%b
} G*rlU
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publicvoid setQueryCacheRegion(String 2q%vd=T
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queryCacheRegion){ dR
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this.queryCacheRegion = yIma7H@=L
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queryCacheRegion; &9\8IR >
} e2L4E8ST<
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publicvoid save(finalObject entity){ Y%@a~|
getHibernateTemplate().save(entity); vABUUAo!Jr
} 3V@!}@y,F6
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publicvoid persist(finalObject entity){ .X{U\{c| a
getHibernateTemplate().save(entity); aui3Mq#f
} (zIIC"~5
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publicvoid update(finalObject entity){ O@sJ#i>
getHibernateTemplate().update(entity); _Wgpk0
} Bngvm9k3
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publicvoid delete(finalObject entity){ [M&.'X
getHibernateTemplate().delete(entity); =x}p>#o,J
} Qi\"b
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publicObject load(finalClass entity, ZA'Qw2fF0
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finalSerializable id){ 6G]hsgro
return getHibernateTemplate().load Kp%:\s,lO
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(entity, id); 7q'T,'[
} 0M 5m8
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publicObject get(finalClass entity, 0p1~!X=I
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*
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finalSerializable id){ Q(h/C!rKe
return getHibernateTemplate().get T {zz3@2?
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(entity, id); ::8c pUc`f
} QW_W5|_
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publicList findAll(finalClass entity){ |oV_7%mlu
return getHibernateTemplate().find("from 9O\N
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" + entity.getName()); 29r (Y
} Wtqv
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publicList findByNamedQuery(finalString Eg 8rgiU
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namedQuery){ tzdh3\6F
return getHibernateTemplate C!6d`|
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().findByNamedQuery(namedQuery); uZ8^" W
} tW}At
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publicList findByNamedQuery(finalString query, OzS/J;[PO[
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finalObject parameter){ m!_*Q
return getHibernateTemplate A7=k9|
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().findByNamedQuery(query, parameter); d{:0R9
} a F%V
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publicList findByNamedQuery(finalString query, /'Q2TLy=
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finalObject[] parameters){ 22r$Ri_>
return getHibernateTemplate ;eT+Ly|{
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().findByNamedQuery(query, parameters); >j_N6B!
} Tb<}GcwJ
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publicList find(finalString query){ L}\~)
return getHibernateTemplate().find jC_m0Iwc
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(query); ^{l$>e]
} 3jDAj!_ea
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publicList find(finalString query, finalObject !nt[J$.z^
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parameter){ v 5dLjy5
return getHibernateTemplate().find .l +yK-BZ
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(query, parameter); [LDY;k~5+
} vnD `+y
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public PaginationSupport findPageByCriteria 0*XCAnJ^_
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(final DetachedCriteria detachedCriteria){ nV3I6
return findPageByCriteria a+PVi
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?yy,3:
} -SN6&-#c_
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public PaginationSupport findPageByCriteria QI*<MF,1
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(final DetachedCriteria detachedCriteria, finalint v]X*(e
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startIndex){ xvTz|Y
return findPageByCriteria pgEDh^[MW
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(detachedCriteria, PaginationSupport.PAGESIZE, VQl(5\6O
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startIndex); -)Of\4kx
} y{Vh?Z<E
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public PaginationSupport findPageByCriteria Q%n$IQr4gM
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(final DetachedCriteria detachedCriteria, finalint `/JuItL-
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pageSize, }0idFotck
finalint startIndex){ }) Zcw1g
return(PaginationSupport) =SVb
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getHibernateTemplate().execute(new HibernateCallback(){ Aqo90(jffx
publicObject doInHibernate r>cN,C
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(Session session)throws HibernateException { 6o<(,\ad[
Criteria criteria = |(3"_
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detachedCriteria.getExecutableCriteria(session); w:07_`cH=
int totalCount = ug^esB
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((Integer) criteria.setProjection(Projections.rowCount ppzQh1
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()).uniqueResult()).intValue(); a6!|#rt
criteria.setProjection t4Pi <m:7
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(null); JsHD3
List items = hO; XJyv
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criteria.setFirstResult(startIndex).setMaxResults T(
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(pageSize).list(); aKz:hG
PaginationSupport ps = _)[UartKx
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new PaginationSupport(items, totalCount, pageSize, #jM-XK
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startIndex); P7\?WN$p
return ps; Z7p!YTA
} 8\Bb7*
}, true); K/M2L&C
} q![`3m-d.
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public List findAllByCriteria(final IPf>9#L
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DetachedCriteria detachedCriteria){ zD;k|"e
return(List) getHibernateTemplate uR6 `@F
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().execute(new HibernateCallback(){ "{[\VsX|c
publicObject doInHibernate xSq{pxX
Z): Nd9
(Session session)throws HibernateException { }CL7h;5N 3
Criteria criteria = oS^KC}X
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detachedCriteria.getExecutableCriteria(session); ]94`7@
return criteria.list(); `IT]ZAem`/
} vUhgM'
}, true); GglGFXOL-
} 45rG\$%#
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public int getCountByCriteria(final sO{TGk]*
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DetachedCriteria detachedCriteria){ qHnX)
Integer count = (Integer) es<8"CcP
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getHibernateTemplate().execute(new HibernateCallback(){ SG]Sx4fg,Y
publicObject doInHibernate k$ b)
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(Session session)throws HibernateException { fZrh_^yH
Criteria criteria = LGK@taw^
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detachedCriteria.getExecutableCriteria(session); Xw3j(`w$,
return c(aykIVOo
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criteria.setProjection(Projections.rowCount ,Oe:SZJ>
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()).uniqueResult(); <~P!yL r
} %OOkPda
}, true); DTG-R>y^
return count.intValue(); Jj?HOtaM
} O]'2<;
} RL3*fRlb
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用户在web层构造查询条件detachedCriteria,和可选的 #nw+U+qL
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 sUU[QP-
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PaginationSupport的实例ps。 `]^W#6l
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ps.getItems()得到已分页好的结果集 .f"1(J8
ps.getIndexes()得到分页索引的数组 [S1 b\f#
ps.getTotalCount()得到总结果数 %uCsCl
ps.getStartIndex()当前分页索引 |Z)}-'QUJ
ps.getNextIndex()下一页索引 ] E:NmBN<
ps.getPreviousIndex()上一页索引 5z =}o/?
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}
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 {xeJO:M3/
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Qj|rNeM_
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一下代码重构了。 lrj&60R`w
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我把原本我的做法也提供出来供大家讨论吧: b$yIM
m2"wMt"*V
首先,为了实现分页查询,我封装了一个Page类: *V7mM?
java代码: Yxbg _RQm
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/*Created on 2005-4-14*/ r}es_9*~Z
package org.flyware.util.page; YC')vv3o(
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/** '&e8;X
* @author Joa FvY=!U06
* k1oJ<$Q
*/ {@F'BB\
publicclass Page { = pn;b1=
~M8|r!_
/** imply if the page has previous page */ Cf9{lhE8
privateboolean hasPrePage; 6 &0r/r
v?
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/** imply if the page has next page */ %S%IW
privateboolean hasNextPage; Hi$R"O
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/** the number of every page */ uAqiL>y
privateint everyPage; ')0@J`
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/** the total page number */ U[02$gd0l
privateint totalPage; DxwR&S{
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/** the number of current page */
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privateint currentPage; K4jHha
('7$K
/** the begin index of the records by the current df$.gP
w%s];EE
query */ :L@n(buRN
privateint beginIndex; s .<.6t:G4
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/** The default constructor */ $y&W:
public Page(){ 8["%e#%`$
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} ]XbMqHGS
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/** construct the page by everyPage / Ws>;0
* @param everyPage Sc/l.]k+
* */ u*):
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public Page(int everyPage){ } 6!/Nb
this.everyPage = everyPage; C#nT@;VO5
} 2.I|8d[
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/** The whole constructor */ \*=wm$p&*
public Page(boolean hasPrePage, boolean hasNextPage, 9?MzIt
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int everyPage, int totalPage, )~)l^0X
int currentPage, int beginIndex){ nH&z4-1Y?
this.hasPrePage = hasPrePage; NLY=o@<
this.hasNextPage = hasNextPage; RrvC}9ar
this.everyPage = everyPage; IH dA2d?.]
this.totalPage = totalPage; ,|s*g'u
this.currentPage = currentPage; A5J41yH
this.beginIndex = beginIndex; v}N\z2A
} |(Mxbprz
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/** $BMXjXd}
* @return :MY=Q]l
* Returns the beginIndex. \Q(a`6U
*/ P*BRebL:
publicint getBeginIndex(){ lYCvYe
return beginIndex; Qy0w'L/@
} bf0,3~G,P
F5RL+rU(h
/** T>'O[=UWh
* @param beginIndex ,wes*
* The beginIndex to set. #55:qc>m
*/ 4qp|g'uXT
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; )f|`mM4DW!
} WM?-BIlT=
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/** -
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* @return #i@f%Bq-
* Returns the currentPage. TDDMx |{
*/ yy=hCjQ)
publicint getCurrentPage(){ $
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return currentPage; U%s@np
} ];hqI O#nM
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/** t&?{+?p:
9
* @param currentPage /]3[|
* The currentPage to set. q+\<%$:u
*/ 2I [zV7 @t
publicvoid setCurrentPage(int currentPage){ `
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this.currentPage = currentPage; wQUl!s7M;
} &&9|;0<
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/** ,M.}Q ak^
* @return o& FOp'
* Returns the everyPage. rL1yq|]I
*/ HvG %##
publicint getEveryPage(){ [oVM9Q
return everyPage;
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} zp;!HP;/=
1*u]v{JJ(
/** >-I <`y-H
* @param everyPage ]|tg`*l!>
* The everyPage to set. Cjr]l!
*/ RbTGAA
publicvoid setEveryPage(int everyPage){ v#qd q!64
this.everyPage = everyPage; KJ'ID
} qx5`lm~L
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/** c%/b*nQ(=
* @return >|A,rE^Ojt
* Returns the hasNextPage. S[3"?$3S
*/ ,~naKd.ZY
publicboolean getHasNextPage(){ g=$U&Hgs
return hasNextPage; 8xO
} GLtd<M"
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/** 8l5>t
* @param hasNextPage 9y*] {IY
* The hasNextPage to set. dYrgL3'
*/ ud`-w
publicvoid setHasNextPage(boolean hasNextPage){ ]##aAh-P4&
this.hasNextPage = hasNextPage; hU""YP~y
} 9KU&M"Yq&i
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/** d-_V*rYU
* @return X?'cl]1?
* Returns the hasPrePage. +_7a/3kh
*/ f"FFgQMkv
publicboolean getHasPrePage(){ ad: qOm
return hasPrePage; .g*N+T6O
} X>[i<ei
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/** mp8GHV
* @param hasPrePage 88osWo6rG
* The hasPrePage to set. C12UZE;
*/ ,XO@ZBOM
publicvoid setHasPrePage(boolean hasPrePage){ "TJu<O"2
this.hasPrePage = hasPrePage; xc#t8`
} N x&/p$d
~|}]
/** ^ f! M"@
* @return Returns the totalPage. 9-c3@>v
* 8<C*D".T$
*/ =%7drBo D
publicint getTotalPage(){ nXRa_M(z8
return totalPage; L5FOlzn
} [_'A(.
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/** }:IIk-JoC
* @param totalPage fwz:k]vk
* The totalPage to set. G{} 2"/
*/ jjV'`Vy)
publicvoid setTotalPage(int totalPage){ \s*M5oN]]
this.totalPage = totalPage; d. vNiq,`
} n>ui'}L
TF/NA\0c$
} U*r54AyP
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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 (+|+ELfqW
5I2,za&e
个PageUtil,负责对Page对象进行构造: QXZXj#`
java代码: jU&m*0nL
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,-AF8BP
/*Created on 2005-4-14*/ Czjb.c:a.Y
package org.flyware.util.page; L\2"1%8Wj
H[~ D]RG}'
import org.apache.commons.logging.Log; "#O9ij
import org.apache.commons.logging.LogFactory; d&NnpjH}c
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/** Q ]CMm2L^f
* @author Joa @njNP^'Kx
* "u^Erj# /
*/ Nu"v
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publicclass PageUtil { |eu8;~A
;_bRq:!j;
privatestaticfinal Log logger = LogFactory.getLog Uqel
UL}
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(PageUtil.class); _aFe9+y
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4
/** M~2Us{ `
* Use the origin page to create a new page kg^0 %-F
* @param page hU$o^ICH
* @param totalRecords |0i{z(B
* @return [MpWvLP"x
*/ 7
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publicstatic Page createPage(Page page, int E5^\]`9P
>N |?>M*
totalRecords){ D m0)%#
return createPage(page.getEveryPage(), qf x*a88
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page.getCurrentPage(), totalRecords); M1/d7d
} 12Oa_6<\0;
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/** t.9s4 9P
* the basic page utils not including exception (.:*GUg
A] |w1nq
handler O-V|= t
* @param everyPage DPT6]pl"y
* @param currentPage K+}0:W=P
* @param totalRecords EQ$k^Y8 "
* @return page UDG1F_&h
*/ 9)oi_U.
publicstatic Page createPage(int everyPage, int r%=-maPL[
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currentPage, int totalRecords){ 2GptK"MrD
everyPage = getEveryPage(everyPage); PMytk`<`zw
currentPage = getCurrentPage(currentPage); cHvm
int beginIndex = getBeginIndex(everyPage, JUr
t%2
b{<?E };%
currentPage); YCDH 0M
int totalPage = getTotalPage(everyPage, SI!A?34
T aS1%(
totalRecords); KkCGL*]K
boolean hasNextPage = hasNextPage(currentPage, |cU75
S 1
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totalPage); o`iA&
boolean hasPrePage = hasPrePage(currentPage); l5T[6C
@}4aF|
returnnew Page(hasPrePage, hasNextPage, P2'N4?2
everyPage, totalPage, (mIjG)4t
currentPage, p]mN)
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beginIndex); fxd+0R;f
} '[WL8,.Q
9f!
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privatestaticint getEveryPage(int everyPage){ ~$u9
return everyPage == 0 ? 10 : everyPage; }:2##<"\t
} ^m#tWb)f
T[SK>z
privatestaticint getCurrentPage(int currentPage){ =@!t/LR7kg
return currentPage == 0 ? 1 : currentPage; ;stjqTd
} hW#^H5?
-P}A26qB
privatestaticint getBeginIndex(int everyPage, int VL*KBJ
H{Ewj_L
currentPage){ X)KCk2Ax
return(currentPage - 1) * everyPage; /JS_gr@DK
} S9Sgd&a9
P PJ^;s
privatestaticint getTotalPage(int everyPage, int HV~Fe!J_
Rn?JMM]
totalRecords){ #s{^fUN6
int totalPage = 0; '{ _ X1
\\R}3 >Wc
if(totalRecords % everyPage == 0) E]'
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totalPage = totalRecords / everyPage; O^cC+@l!4
else %6 *c40
totalPage = totalRecords / everyPage + 1 ; Z<;W*6J
N
(4H}2
return totalPage; ~2Wus8X-
} %+l95Dv1
n[Q(q[ULV
privatestaticboolean hasPrePage(int currentPage){ J1G}l5N
return currentPage == 1 ? false : true; q SNCBn '
} UQDAql
MKfK9>a
privatestaticboolean hasNextPage(int currentPage, pT|s#-}
G=zNZ
int totalPage){ vclc%ws
return currentPage == totalPage || totalPage == =Ydrct
>=0]7k;
0 ? false : true; 5?^#v
} ^s{F f+]W
0#WN2f, <:
?b+Y])SJK
} ~P'.R.e
4gen,^ Ij
}.A]=Ew
!Vyf2xS"
)h,yQ`.
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。 _bCAZa&&
!i torSl
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 q@wD@_
G?}?>O
做法如下: 6Hnez @d
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Dz0D ^(;V
_8.TPB]no
的信息,和一个结果集List: \8xSfe
java代码: -yf8
_
dAyw
$BdwKk
!k
/*Created on 2005-6-13*/ uA#K59E+
package com.adt.bo; [\W&
4H6Fq*W{k
import java.util.List; d3c.lD)L9
Tow=B
import org.flyware.util.page.Page; Rt?CE jy
Pg8.RvmQ
/** 4;AF\De
* @author Joa $bG*f*w
*/ J]U_A/f
publicclass Result { !MKecRG_
)J[m>tyY5
private Page page; Z9DfwWI2nu
N)"8CvQL
private List content; [_JdV(]$
vi}16V84l
/** v/ N[)<
* The default constructor Ro]Z9C>1o
*/ `-{l$Hn9|~
public Result(){ *,z/q6
super(); s>/Xb2\
} {g.YGO
YIRe__7-NU
/** n}UJ-\$
* The constructor using fields G*4I;'6
* c
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* @param page xeFx!$3
* @param content ee?
d?:L
*/ >8"(go+02
public Result(Page page, List content){ FygNWI '
this.page = page; >pp/4Ia!
this.content = content; ycBgr,Ynu<
} 0;l~B
h}a}HabA
/** mFTuqujO
* @return Returns the content. i F+:j8
b
*/ g8.z?Ia#5Z
publicList getContent(){ IB&G#2M<
return content; /ugWl99.W
} 8|zavH#P
n$C-^3c
/** nriSVGi
* @return Returns the page. :k_&Zd j,B
*/ C~T,[U
public Page getPage(){ 4*}&nmW
return page; 2A\b-;4EP
} r<ww%2HTS
LL
e*|:
/** p/(Z2N"
* @param content #$Zx ].[lc
* The content to set. p? L%'
*/ {Phq39g
public void setContent(List content){ QQW}.>N
this.content = content; :6(\:
} )G)6D"5,+G
RyK~"CWT
/** |p/*OFC6
* @param page /p<9C?
* The page to set. 4,;*sc 6*
*/ =x-7 Wy
publicvoid setPage(Page page){ /[_aK0U3
this.page = page; )IcSdS0@M
} 5! );4+
} lC#wh2B6
Q!q6R^5!K
d'W2I*Zc<
y>=Y MD
uMDd Zj&
2. 编写业务逻辑接口,并实现它(UserManager, $=.%IJ_MAz
&j:e<{@
UserManagerImpl) :O413#8
java代码: Pp }Z"
9;LjM ~Ct
2FuV%\p
/*Created on 2005-7-15*/ =W7-;&
package com.adt.service; h|]cZMGo
OpaRQ=
import net.sf.hibernate.HibernateException; :j`f%Vg~x
[@9S-$Xa
import org.flyware.util.page.Page; _{`Z?lt
>s5}pkAv|e
import com.adt.bo.Result; z"
tz-~
h)Fc<,vwBE
/** BX$<5S@
* @author Joa "9P @bA
*/ ^5s7mls
publicinterface UserManager { `n>|rd
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public Result listUser(Page page)throws sAc1t`
R*pPUw\yn
HibernateException; kFE9}0-
*{VC<<`
} cRs.@U\{R\
</;e$fh`
{{G3^ysa
AM=,:k$
)ItABl[{
java代码: [ifw}(
b\JU%89
F?'
/*Created on 2005-7-15*/ .bY>++CAPA
package com.adt.service.impl; vQCb?+X&
I8!>7`L
import java.util.List; u)Kiwa
D4c'6WGb@
import net.sf.hibernate.HibernateException; f~W+Rt7o
9_wDh0b~p
import org.flyware.util.page.Page; O^!ds
import org.flyware.util.page.PageUtil; SLEOcOAmD
Evj%$7H1L1
import com.adt.bo.Result; SAq.W"ri
import com.adt.dao.UserDAO; 8TpYt)]S
import com.adt.exception.ObjectNotFoundException; ((`\i=-o5
import com.adt.service.UserManager; nam]eW
Jw5@#j
/** oo;<I_#07
* @author Joa \bT0\
(Js\
*/ }*bp4<|
publicclass UserManagerImpl implements UserManager { <eEIR
B](R(x>L
private UserDAO userDAO; 33<{1Y[Q6E
0p.MH~mx
/** zwC ,,U
* @param userDAO The userDAO to set. 5{(4%
*/ .+S%hT,v6i
publicvoid setUserDAO(UserDAO userDAO){ sxr,]@
this.userDAO = userDAO; d 8;kM`U
} itNuY<"
Fk49~z
/* (non-Javadoc) cEa8l~GC<
* @see com.adt.service.UserManager#listUser Fy\q>(v.
n@tt.n!{l
(org.flyware.util.page.Page) xGyl7$J
*/ *bo| F%NAz
public Result listUser(Page page)throws kttJTP77t
{Y5@SIyE
HibernateException, ObjectNotFoundException { B`)sc ~u
int totalRecords = userDAO.getUserCount(); !2Ompcr1
if(totalRecords == 0) 1\,k^Je7
throw new ObjectNotFoundException Gjeb)Y6N
g"" 1\rc=
("userNotExist");
;@k=9o]A
page = PageUtil.createPage(page, totalRecords); 1c QF(j_
List users = userDAO.getUserByPage(page); &Ih }"
returnnew Result(page, users); <_8bAO8\
} )SP"V~^Wn
g%=K
rO
} fsPsP`|
qN1fWU#$
rD21:1s
ShL!7y*rT{
F(.`@OO
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 dH5*%
hN K wQ
询,接下来编写UserDAO的代码: 43h06X`
3. UserDAO 和 UserDAOImpl: HqsqUS3[
java代码: cQ<|Of
9Vq
;UXV!8SM
/*Created on 2005-7-15*/ >'Lkn2WI
package com.adt.dao; UH0l8ixc
@{RhO|UR
import java.util.List; Y$XzZ>VW
::{\O\w
import org.flyware.util.page.Page; z59;Qk
JtY$AP$
import net.sf.hibernate.HibernateException; [xY-=-T*4
~q+AAWL
/** UTE6U6
* @author Joa 4jDi3MMU9
*/ yw:%)b{
publicinterface UserDAO extends BaseDAO { XM5)|D
(PH7nW7
publicList getUserByName(String name)throws W=EcbH9/.)
5Q%)|(U'
HibernateException; _)<5c!
uQbag]&j
publicint getUserCount()throws HibernateException; ;;i419
SVwxK/Fci
publicList getUserByPage(Page page)throws DM v;\E~D
zmZU"eWp)
HibernateException; E>
pr})^w
Z] r9lC
} +JG05h%'
k@%5P-e}
>{(c\oMD
k(tB+k!vH\
!21G$[H
java代码: (rJ-S"^u
3}g>/F~
6d8)]
/*Created on 2005-7-15*/ L"vk ^>E6
package com.adt.dao.impl; 6 Q7MAP M
}@6yROy.
import java.util.List; j<)$ [v6
!nL94:8U
import org.flyware.util.page.Page; Ff>X='{
5l@}1n
import net.sf.hibernate.HibernateException; [u*7( 4e
import net.sf.hibernate.Query; :j3^p8]
yj'lHC
import com.adt.dao.UserDAO; > .}G[C
X}
V]3
/** B>'J5bZsw
* @author Joa mpD.x5jm<
*/ h`! 4`eI
public class UserDAOImpl extends BaseDAOHibernateImpl Ff0V6j)ji
([a;id
implements UserDAO { U~sC%Ri-@U
q("l?'
/* (non-Javadoc) Am3j:|>*
* @see com.adt.dao.UserDAO#getUserByName rZ.=Lq
Z%ZOAu&p
(java.lang.String) )CoFRqz<h
*/ um]N]cCD`
publicList getUserByName(String name)throws ! 1?u0
.$d:c61X
HibernateException { +KExK2=
String querySentence = "FROM user in class 3,i`FqQa
>cjxu9Vr1K
com.adt.po.User WHERE user.name=:name"; %r6_['T
Query query = getSession().createQuery D->E& #
fh_:ung
(querySentence); jX' pUO
query.setParameter("name", name); @|<nDd{2
return query.list(); k}kwr[
} wp8-(E^
VIGLl'8p
/* (non-Javadoc) 0)PZS>
* @see com.adt.dao.UserDAO#getUserCount() ZR3sz/ulLd
*/ :T6zT3(")D
publicint getUserCount()throws HibernateException { 8Rw:SU9H?T
int count = 0; -$%~EY}
String querySentence = "SELECT count(*) FROM ~ cu+QR)
c uAp,!
user in class com.adt.po.User"; K4Nz I9@
Query query = getSession().createQuery liB~vdqj
^cW{%R>XY
(querySentence); =$~x]
count = ((Integer)query.iterate().next b)XGr?
|1!|SarM{B
()).intValue(); c\P}ZQ
return count; tIBEja^l
} {hO|{vz
Y8s-cc(
/* (non-Javadoc) @:'E9J06
* @see com.adt.dao.UserDAO#getUserByPage N8r+Q%ov
`.VkR5/
(org.flyware.util.page.Page) PMQ31f/zf
*/ c}=[r1M*
publicList getUserByPage(Page page)throws vcy+p]6KE-
Nt<Ac&6
s
HibernateException { WpI5C,3Z!l
String querySentence = "FROM user in class m^0*k|9+G
?~}8^~3
com.adt.po.User"; A1zV5-E/
Query query = getSession().createQuery o'P[uB/
*"/BD=INv}
(querySentence); w+%p4VkA<r
query.setFirstResult(page.getBeginIndex()) Y\1& Uk
.setMaxResults(page.getEveryPage()); r 3T #Nv
return query.list(); bw#\"uJ
} s5d[sx
tUfze9m
} odcrP\S
jP3 ~O
blbzh';0}
'i/"D8
nM$-L.dG
至此,一个完整的分页程序完成。前台的只需要调用 {;UBW7{
OH+2)X
userManager.listUser(page)即可得到一个Page对象和结果集对象 z"sv,W
NlG!_D"(y
的综合体,而传入的参数page对象则可以由前台传入,如果用 aI\>=*HF
ok&v+A
webwork,甚至可以直接在配置文件中指定。 .$x822
Si#XF[/
下面给出一个webwork调用示例: _{i-.;K
java代码: 99q$>nx,w
g;3<oI/P
&19z|Id
/*Created on 2005-6-17*/ ON_GD"
package com.adt.action.user; kA 4kQ}q
'_=XfTF
import java.util.List; !Nhq)i
'aZAWY d
import org.apache.commons.logging.Log; \HJ t }
import org.apache.commons.logging.LogFactory; T:j!a{_|
import org.flyware.util.page.Page; s.}:!fBk
{-5b[m(
import com.adt.bo.Result; 7XIG ne%v
import com.adt.service.UserService; }W]k1Bsx
import com.opensymphony.xwork.Action; f7]C1!]
QF_K^(
/** #Bn7Cc
* @author Joa o648
xUP
*/ l>>,~
publicclass ListUser implementsAction{ @2$iFZq~
U./1OZ&
privatestaticfinal Log logger = LogFactory.getLog %eqL)pC]
}5;3c %
(ListUser.class); J&b&*3
^UpwVKdP
private UserService userService; (e{pAm
0.t1p(x;
private Page page; W&