Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 (&xIBF_6
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &U{"dJ r
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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 KJCi4O&
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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 d;E
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分页支持类: *FC26_pH
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java代码: v0,&wdi
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package com.javaeye.common.util; cPg$*,]
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import java.util.List; k*o>ZpjNH
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publicclass PaginationSupport { Ahrtl6@AS
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publicfinalstaticint PAGESIZE = 30; FXo{|z3
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privateint pageSize = PAGESIZE; "<1-9CMl
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privateList items; _NB8>v
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privateint totalCount; $[g8j`or!
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privateint[] indexes = newint[0]; &8@
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privateint startIndex = 0; Ufv0Xj
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public PaginationSupport(List items, int </33>Fu)
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totalCount){ (m&''yaH
setPageSize(PAGESIZE); :my@Oxx4@
setTotalCount(totalCount); cDqj&:$e
setItems(items); V(<(k,8=
setStartIndex(0); .tt= \R
} wZ\% !#}7
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public PaginationSupport(List items, int A^@,Ha
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totalCount, int startIndex){ x(bM
setPageSize(PAGESIZE); (5&l<u"K~
setTotalCount(totalCount); &E$:^a4d
setItems(items); d{~Qd|<rr
setStartIndex(startIndex); g%2twq_
} :IX_}|
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public PaginationSupport(List items, int .Af H>)E
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totalCount, int pageSize, int startIndex){ |
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setPageSize(pageSize); g0"KCX
setTotalCount(totalCount); -K U@0G
setItems(items); Wkc^?0p
setStartIndex(startIndex); VO+3@d:
} ["XS|"DM
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publicList getItems(){ E K#ib
return items; eVB.g@%T
} p="K4E8~H
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publicvoid setItems(List items){ dX;G[\
this.items = items; 77o&$l,A|
} `%Uz0h F
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publicint getPageSize(){ 2mVLR;s{_
return pageSize; J&jig?t
} aFV d}RO0
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publicvoid setPageSize(int pageSize){ R;Gf3K
this.pageSize = pageSize; ~[9(}UM
} 70{fl
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publicint getTotalCount(){ AlQ
return totalCount; :h)A/k_
} @AAkEWo)_
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publicvoid setTotalCount(int totalCount){ Trwk9 +
if(totalCount > 0){ MtIhpTX
this.totalCount = totalCount; ZeP3
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int count = totalCount / z]F4Z'(e.
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pageSize; m=p<.%a
if(totalCount % pageSize > 0) AC9#!#
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count++; mB]Y;R<
indexes = newint[count]; \J?5Kl[*c
for(int i = 0; i < count; i++){ >5}jM5$
indexes = pageSize * Dt8wd,B
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i; b6~MRfx`7
} |?
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}else{ n*U+jc
this.totalCount = 0; +i.b&PF'H
} >!|(n@
} ?{M!syD<
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publicint[] getIndexes(){ /"%QIy'{
return indexes; Il9pL~u
} O`W&`B(*k
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publicvoid setIndexes(int[] indexes){ 1F_ 1bAh$
this.indexes = indexes; zPT!Fa`
} &.t|&8-
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publicint getStartIndex(){ p$A` qx<M_
return startIndex; 95CCje{o_
} smt6).o
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publicvoid setStartIndex(int startIndex){ K;_.WzWD=
if(totalCount <= 0) H<6/i@ly
this.startIndex = 0; ,0R2k `m!
elseif(startIndex >= totalCount) W!G2$e6
this.startIndex = indexes pr(16P
CF k^(V"
[indexes.length - 1]; N}2xt)JZz
elseif(startIndex < 0) Fl^}tC
this.startIndex = 0; k(v8zDq*
else{ * 5Y.9g3)Q
this.startIndex = indexes 4? a!6
2!^[x~t
[startIndex / pageSize]; -O=a"G=
} (iZE}qf7g
} Aa;s.:?
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publicint getNextIndex(){ #815h,nP+
int nextIndex = getStartIndex() + Rtl;*ZAS
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pageSize; bUp
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if(nextIndex >= totalCount) ?>p<!:E!r
return getStartIndex(); r&|-6OQZZ
else VIxt;yE
return nextIndex; kGZ_/"iuO
} (]mh}=:KDg
K$..#]\TM
publicint getPreviousIndex(){ B R-(@
int previousIndex = getStartIndex() - uUczD 8y
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pageSize; &)p/cOiV
if(previousIndex < 0) hL,+wJ+A
return0; D~xUr)E
else M7(vI4V
return previousIndex; 0Up@+R2
} %q@eCN
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} C||A[JOS
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抽象业务类 Gd~Xvw,u
java代码: U$`)|/8
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/** h
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* Created on 2005-7-12 O]n"aAu@
*/ e_wz8]K)n
package com.javaeye.common.business; }V3p <
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import java.io.Serializable; 4><b3r;T'
import java.util.List; )CzWq}:
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import org.hibernate.Criteria; 6?0^U 9
import org.hibernate.HibernateException; 22|f!la8n
import org.hibernate.Session; ~7!J/LHg
import org.hibernate.criterion.DetachedCriteria; SrN;S kS
import org.hibernate.criterion.Projections; ]rDf3_!m(
import &DFe+y~PR
$;_'5`xs
org.springframework.orm.hibernate3.HibernateCallback; S#X$QD
import 'r%`(Z{~
daaEN(
org.springframework.orm.hibernate3.support.HibernateDaoS SPIYB/C
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upport; fz
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import com.javaeye.common.util.PaginationSupport; ,sk;|OAI
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public abstract class AbstractManager extends 0*%j6*XDq9
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HibernateDaoSupport { I~qS6#%r
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privateboolean cacheQueries = false; k3[
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privateString queryCacheRegion; _VR Sdr5
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publicvoid setCacheQueries(boolean #Xri%&~
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cacheQueries){ jz|zq\Eek
this.cacheQueries = cacheQueries; '
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} LS?hb)7
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publicvoid setQueryCacheRegion(String Um\Nd#=:
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queryCacheRegion){ .b vB8VOrW
this.queryCacheRegion = ^" ywltW>
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queryCacheRegion; iLy}G7h
} UUv&X+Y
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publicvoid save(finalObject entity){ TeQWrms
getHibernateTemplate().save(entity); v|jBRKU99
} e(BF=gesgp
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publicvoid persist(finalObject entity){ @4h .?
getHibernateTemplate().save(entity); ]}F_nc2L
} fk P@e3
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publicvoid update(finalObject entity){ sRo%=7Z
getHibernateTemplate().update(entity); r,i^-jv;
} tCK%vd%
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publicvoid delete(finalObject entity){ [e ;K$
getHibernateTemplate().delete(entity); :n>m">4
} XN]kNJX
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publicObject load(finalClass entity, K|Std)6
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finalSerializable id){ ;,Sl+)@h
return getHibernateTemplate().load ?D\6CsNp(2
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(entity, id); j0o_``
} ?YX2CJ6N
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publicObject get(finalClass entity, PR~ho&!
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finalSerializable id){ "sf8~P9qy
return getHibernateTemplate().get ^Ebaq`{V\'
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(entity, id); .BlGV 2@^#
} zF(I#|Vo
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publicList findAll(finalClass entity){ rjQV;kX>
return getHibernateTemplate().find("from &~G>pvZ
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" + entity.getName()); G(|ki9^@"9
} {DBgW},
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publicList findByNamedQuery(finalString ve=oH;zf
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namedQuery){ $PstThM
return getHibernateTemplate #+QwRmJdT!
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().findByNamedQuery(namedQuery); A%oHx|PD
} e0+N1kY
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publicList findByNamedQuery(finalString query, ,#UaWq@7
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finalObject parameter){ (m=-oQ&Ro
return getHibernateTemplate }!(cm;XA"
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().findByNamedQuery(query, parameter); =cM\o{ q
} ,K6s'3O(LW
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publicList findByNamedQuery(finalString query, ?H0 #{!s
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finalObject[] parameters){ 3F[z]B
return getHibernateTemplate tV@!jaj\
7
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().findByNamedQuery(query, parameters); 7:R8QS9
} yiSv#wD9
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publicList find(finalString query){ \$V~kgQ0
return getHibernateTemplate().find YT}m
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(query); l^%Ez?-:s
} /'u-Fr(Q+
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publicList find(finalString query, finalObject I/<aY*R4
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parameter){ dMQtW3stY
return getHibernateTemplate().find ((N<2G)
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(query, parameter); |jk"; h
} xYRN~nr
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public PaginationSupport findPageByCriteria X.}:gU-
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(final DetachedCriteria detachedCriteria){ YbND2i
return findPageByCriteria gb|C592R5C
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); C!]hu)E
} g[0b>r7
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public PaginationSupport findPageByCriteria D?)91P/R
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(final DetachedCriteria detachedCriteria, finalint <6)Ogv",
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startIndex){ 81O`#DfZ
return findPageByCriteria 5yI_uQR
'mp@!@_
(detachedCriteria, PaginationSupport.PAGESIZE, 8Sd<!
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startIndex); !0CC &8C`
} #pErGz'{
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public PaginationSupport findPageByCriteria Vi?[yu<F
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(final DetachedCriteria detachedCriteria, finalint JZNRMxu
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pageSize, $5jQm,V$K
finalint startIndex){ >Olg
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return(PaginationSupport) -Id4P _y
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getHibernateTemplate().execute(new HibernateCallback(){ ) kfA5xi[
publicObject doInHibernate WId"2W3M
[
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(Session session)throws HibernateException { $d3al%Uo
Criteria criteria = lRF04
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detachedCriteria.getExecutableCriteria(session); n#Q ;bSw
int totalCount = O; 7`*}m
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((Integer) criteria.setProjection(Projections.rowCount p#wQW[6
s {p-cV
()).uniqueResult()).intValue(); W,9. z%
criteria.setProjection {Iy<iV
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(null);
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List items = 0?8O9i
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criteria.setFirstResult(startIndex).setMaxResults Hm!ffqO_
:hr% 6K7
(pageSize).list(); hCV e05
PaginationSupport ps = wmAZ {
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new PaginationSupport(items, totalCount, pageSize, 18f!k
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startIndex); hOw
return ps; S.pL^Ru
} ecDni>W
}, true); V9&7K65-1
} <ZcJC+k
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public List findAllByCriteria(final D!Pv`wm
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DetachedCriteria detachedCriteria){ @M-i$
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return(List) getHibernateTemplate cH%qoHgx
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().execute(new HibernateCallback(){ 'APtY;x^{
publicObject doInHibernate bnHQvCO3$
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(Session session)throws HibernateException { un([3r
Criteria criteria = a9]F.Jm
}N[|2nR'
detachedCriteria.getExecutableCriteria(session); r@b M3V_o
return criteria.list(); W^#HR
} {9:[nqX
}, true); B3|h$aKC
} P'%#B&LZo
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public int getCountByCriteria(final E-gI'qG\(
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DetachedCriteria detachedCriteria){ tljZE)
Integer count = (Integer) <LL+\kfTZO
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getHibernateTemplate().execute(new HibernateCallback(){ p}H:t24Cr5
publicObject doInHibernate $WmB __
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(Session session)throws HibernateException { t6u>_She
Criteria criteria = ;e
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detachedCriteria.getExecutableCriteria(session); &O8vI,M
return hWc`4xdl
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criteria.setProjection(Projections.rowCount ]nPfIBoS
dpG l
()).uniqueResult(); >=Bl/0YH
} lw+Y_;
}, true); sNB*S{
return count.intValue(); vd<r}3i*
} X!H[/b:1O
} @jh\yj rW
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用户在web层构造查询条件detachedCriteria,和可选的 T:FaD V{
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 a(.q=W
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PaginationSupport的实例ps。 p+x}$&<|
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ps.getItems()得到已分页好的结果集 oF'_x,0
ps.getIndexes()得到分页索引的数组 pQ~Y7
ps.getTotalCount()得到总结果数 E>LZw>^YJ
ps.getStartIndex()当前分页索引 s Zn@y e^
ps.getNextIndex()下一页索引 N"/J1
ps.getPreviousIndex()上一页索引 Pgug!![
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 <TN+-)H6
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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 3R|UbG`
,:[\h\5m
一下代码重构了。 0G;
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我把原本我的做法也提供出来供大家讨论吧: B1^9mV'O
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首先,为了实现分页查询,我封装了一个Page类: |)KOy~"
java代码: V2B@Lq"9`
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/*Created on 2005-4-14*/ TmviYP gb
package org.flyware.util.page; (V(8E%<c
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/** C[ma!he
* @author Joa hqDnmzG
* E;1QD/E$
*/ eP(|]Rk
publicclass Page { !l9i)6W
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/** imply if the page has previous page */ D( \c?X"
privateboolean hasPrePage; kR0/jEz
C
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/** imply if the page has next page */ R1cOUV,y[/
privateboolean hasNextPage; _-=yD@;[D
_^ZBSx09)
/** the number of every page */ 5ho!}K
privateint everyPage; c)`=wDi
!8Y$}
/** the total page number */ V$Zl]f$S
privateint totalPage; Kcu*Z
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/** the number of current page */ m!-R}PQC
privateint currentPage; ]]Fe:>
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/** the begin index of the records by the current #fVk;]u`[3
Hb&C;lk
query */ %\f<N1~*
privateint beginIndex; $V870
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/** The default constructor */ \"7U,y',
public Page(){ 'w"hG$".
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} > I>=/i^
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/** construct the page by everyPage 1j_
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* @param everyPage 'ZFbyt Q2
* */ <SKzCp\
public Page(int everyPage){ 6DuA
this.everyPage = everyPage; 'z9}I
#
} dKpUw9C#/
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/** The whole constructor */ a{
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public Page(boolean hasPrePage, boolean hasNextPage, X..<U}e
{>Yna"p
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int everyPage, int totalPage, Lk lD^AJA
int currentPage, int beginIndex){ Uz_OUTFM
this.hasPrePage = hasPrePage; G,X> f?
this.hasNextPage = hasNextPage; ^k2g60]
this.everyPage = everyPage; *{!E`),FX
this.totalPage = totalPage; e3.q8r
this.currentPage = currentPage; M@]@1Q.p
this.beginIndex = beginIndex; /B!Ik:c}
} ?s5/
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/** d3;Sy`.
* @return -|2k$W
* Returns the beginIndex. s 9n_s=w
*/ =3;~7bYO
publicint getBeginIndex(){ jZgCDA8Mr!
return beginIndex; h f{RI 4Jc
} X?aj0# Q
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/** 9GgXX9K
* @param beginIndex
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* The beginIndex to set. @bIZ0tr4
*/ |hD)=sCj
publicvoid setBeginIndex(int beginIndex){ g[L}puN
this.beginIndex = beginIndex; P$v9
} ne|N!!Dmk
\Lg{GN.
/** 6<o2 0(?
* @return 8}Cp(z2
* Returns the currentPage. AhU
*/ CHckmCgf4
publicint getCurrentPage(){ AOM@~qyc
return currentPage; tjJi|
} a v"dJm
|t6 :4']
/** Hto+spW
* @param currentPage Gt$PBlq0
* The currentPage to set. L2IY$+=M
*/ wCt!.<, .
publicvoid setCurrentPage(int currentPage){ 'M35L30
this.currentPage = currentPage; f{j`d&|
} ]D<3yIGS
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/** #k
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* @return bScW<DZJ-
* Returns the everyPage. /s
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*/ Zvkb=
publicint getEveryPage(){ !@T5]( zV
return everyPage; LMaY}m>
} :Izdj*HL;A
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/** AP9>_0=
* @param everyPage (5GjtFojY|
* The everyPage to set. "+A8w
*/ om{aws;
publicvoid setEveryPage(int everyPage){ o&RNpP*
this.everyPage = everyPage; 9'0v]ar
} !'(QF9%Q
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/** ebiOR1)sN
* @return &~"e["gF=
* Returns the hasNextPage. ;4<!vVf e
*/ !h70 <Q^
publicboolean getHasNextPage(){ ozkmZ;
return hasNextPage; |3C5"R3ZGO
} j/, I)Za
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/** W[qQDn!r
* @param hasNextPage zt2#6v
* The hasNextPage to set. H{g&yo
*/ qa,i:T(w
publicvoid setHasNextPage(boolean hasNextPage){ #@:GLmD%
this.hasNextPage = hasNextPage; 6Ao{Aej|
} (%)<jg1
<P_B|Y4N/
/** f,VJfY?#
* @return ?sclOOh
* Returns the hasPrePage. z4r g.ai
*/ <|;)iT1VeT
publicboolean getHasPrePage(){ pwmH(94$0
return hasPrePage; -Q"
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} i\C~]K~O!
=2/[n8pSsM
/** .9!?vz]1
* @param hasPrePage ?@H/;hB[|
* The hasPrePage to set. y\mK?eR
*/ z+]YB5zK%
publicvoid setHasPrePage(boolean hasPrePage){ ok/{ w
this.hasPrePage = hasPrePage; #T08H,W/
} yZY.B
{
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/** c=<5DC&p
* @return Returns the totalPage. |g!3f
* :|N(:W>=$Y
*/ W$`p ,$ .n
publicint getTotalPage(){ HG&rE3@
return totalPage; =-;J2Qlg6
} L+Q.y~
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/** c52S2f7
* @param totalPage dCO)"]
* The totalPage to set. gUrXaD#
*/ a[7Lqu
publicvoid setTotalPage(int totalPage){ p* tAwl
this.totalPage = totalPage; 6MmkEU z
} 5^Ps(8VbS
_e$T'*q
} t{Z:N']H
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qHE( p+]E
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nE=,=K~
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 A;gU@8m
e2"gzZ4;g
个PageUtil,负责对Page对象进行构造: :NXM.@jJ="
java代码: ,_I#+XiXY
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/*Created on 2005-4-14*/ T*qSk!
package org.flyware.util.page; BL H~`N3U
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import org.apache.commons.logging.Log; h5}:>yc
import org.apache.commons.logging.LogFactory; =v7%IRP5
h.)o4(bO
/** W5R /
* @author Joa 4(TR'_X(
* rfYFS96
*/ a
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publicclass PageUtil { 2)(ynrCe
Y *n[*N
privatestaticfinal Log logger = LogFactory.getLog ^'Qe.DW[
52q<|MW%
(PageUtil.class); D0LoT?$N
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/** eY8rm
* Use the origin page to create a new page d< b ,].
* @param page */y (~O6
* @param totalRecords .a7!*I#g
* @return j S<."a/n
*/ WbGN
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publicstatic Page createPage(Page page, int x#}{z1op9
g @qrVQv
totalRecords){ h4tAaPcS+
return createPage(page.getEveryPage(), ;CLOZ{
@aUQy;
page.getCurrentPage(), totalRecords); E{xcu9
} /eY}0q%
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/** ^(~%'f
* the basic page utils not including exception M&^Iun
1XJLGMW,
handler eKW^\
* @param everyPage "RLv{D<)J,
* @param currentPage $n* wS,
* @param totalRecords cCO2w2A[*
* @return page ;Miag'7
*/ ##BfI`FJ
publicstatic Page createPage(int everyPage, int _7b' i6-
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currentPage, int totalRecords){ P;
9{;
everyPage = getEveryPage(everyPage); L'r gCOJ<
currentPage = getCurrentPage(currentPage); UB,:won
int beginIndex = getBeginIndex(everyPage, a}[ 1*_G
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currentPage); ]h?p3T$h
int totalPage = getTotalPage(everyPage, PAS0 D
#
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totalRecords); 4#lOAzDtv
boolean hasNextPage = hasNextPage(currentPage, 4}Dfi5:
][ 1
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totalPage); # b94S?dq
boolean hasPrePage = hasPrePage(currentPage); n
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returnnew Page(hasPrePage, hasNextPage, >$G'=N:=X&
everyPage, totalPage, B3'-:
currentPage, xL$7bw5fY
c|<E~_.w@
beginIndex); Ft 6{g
JBG
} D2]i*gs
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privatestaticint getEveryPage(int everyPage){ _p;=]#+c&
return everyPage == 0 ? 10 : everyPage; `%Dz 8Z
} 8C8,Q\WV(~
q}cm"lO$
privatestaticint getCurrentPage(int currentPage){ tO+Lf2Ni+
return currentPage == 0 ? 1 : currentPage; ].HHTCD`c
} m aOt/-
T_Cj=>L
privatestaticint getBeginIndex(int everyPage, int +{L=cWA"
SSysOeD+
currentPage){ U o[\1)
return(currentPage - 1) * everyPage; ZK5
wZU
} #D-Ttla
"wnN
0 p
privatestaticint getTotalPage(int everyPage, int 'g:.&4x_w
0bl 8J5Ar5
totalRecords){ D.*o^{w|
int totalPage = 0; k nljc^
74fE%;F
if(totalRecords % everyPage == 0) xl ,(=L]
totalPage = totalRecords / everyPage; %gEgpJd
else ";;Nc>-Y
totalPage = totalRecords / everyPage + 1 ; v@QfxV2
HcCT=x7:
return totalPage; Ot;)zft
} /@Ec[4^=!.
D\^\_r):
privatestaticboolean hasPrePage(int currentPage){ `rb}"V+
return currentPage == 1 ? false : true; fVz0H1\J&
} 8c%_R23
#j4RX:T*[
privatestaticboolean hasNextPage(int currentPage, &vN^*:Q
#:s*Hy=
int totalPage){ dU&hM<.|
return currentPage == totalPage || totalPage == 98XlcI#
7x#."6>Dy
0 ? false : true; i,!t u
} 11?d,6Jl
#oJ%i+V
=[LUOOR*]
} }6!m Q
_~bG[lX !
mr>dZ)
ffR<G&"n~b
>E9 k5
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。 YK>?;U+|
}///k]_Sh
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 L~E|c/
X+QoO=02LR
做法如下: %+@<T<>J<k
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 EIF"{,m
O96%U$W
的信息,和一个结果集List: "f:_(np,
java代码: Ou{VDE
zg$NrI&
m1Xc3=Y
/*Created on 2005-6-13*/ -{ES 36
package com.adt.bo; 2]cU:j6G
@ \*Zq
import java.util.List; I lZ$Jd
!md1~g$rN
import org.flyware.util.page.Page; 6#kmV
1F R
/** )yUSuK(Vu
* @author Joa M\9+?
*/ xM?tdQ~VHY
publicclass Result { )u1=, D
LerRrN}~
private Page page; soh9Oedml-
ZG(Pz9{K
private List content; v.F|8 cG
kL"Y>@H
/** %R P\,|
* The default constructor dy4~~~^A
*/ ^00C"58A
public Result(){ #N'bhs
super(); !+(H(,gI
} =-]NAj\
H`
h]y
/** h/]));p
* The constructor using fields dg#w!etB
* R%"'k<`#
* @param page |LirjC4
* @param content <=%=,Yk
*/ ?%*p!m
public Result(Page page, List content){ :kvQ3E0
this.page = page; (w` j?c1
this.content = content; pYh\l.@qf
} yM*_"z!L
Rbcu5.6
/** H@'u$qr$:
* @return Returns the content. T@d4NF#
*/ O@a7MzJ
publicList getContent(){ O+t'E9Fa
return content; lsU`~3nr
} { a_&L
i93^E~q]
/** D~)bAPAD
* @return Returns the page. hVh,\d&2t
*/ krRnE7\m
public Page getPage(){ f1q0*)fk
return page; \7G.anY
} 5%w08
\S>GtlQbn
/** d
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* @param content 9yp'-RKjw
* The content to set. 4P?@NJp
*/ Y+Cv9U0
public void setContent(List content){ HqXS-TG
this.content = content; $V;0z~&!'
} D{6<,#P{w
M=4`^.Ocm
/** T!-ly7-`
* @param page 3*N0oc^m
* The page to set. 3x>Y
*/ f1
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publicvoid setPage(Page page){ Z<#h$XUA
this.page = page; Lc0=5]D
} ucFfxar"
} =lL)g"xX
Tr,
zV
n@J>,K_B
's$/-AV
.gY=<bG/fA
2. 编写业务逻辑接口,并实现它(UserManager, 2:&L|;
xXCsJ9]
UserManagerImpl) d'[q2y?6N
java代码: z\>ZgRi~n
o@ @| 4
F
^M+aQg%
/*Created on 2005-7-15*/ 0P;\ :-&p
package com.adt.service; (?ZS9&y}
Tj6kCB
import net.sf.hibernate.HibernateException; p5J!j I=
h]&o)%{4
import org.flyware.util.page.Page; _7
^:1i~:.
p
MR4]G
import com.adt.bo.Result; " : V@AT
}brBhe8a
/** dte-2?%~j
* @author Joa f |NXibmP
*/ ,,G'Zur7
publicinterface UserManager { s3=slWY=
r ?z}TtDp
public Result listUser(Page page)throws @ X5#?
~'N+O K
HibernateException; )gV @6w
?L6wky{
} 7h`t-6<!q
1i;Cw/mr
ptlag&Z
)1f.=QZN^;
<t dsUh:?&
java代码: l0eh}d
-m$2"_
.dj}y
jd]f
/*Created on 2005-7-15*/ &;U
F,
package com.adt.service.impl; p,14'HS%@
I7W?}bR*6
import java.util.List; m,&2s-v
*S'?u_Y7
import net.sf.hibernate.HibernateException; h$p}/A
oz7=1;r
import org.flyware.util.page.Page; Qjmo{'d
import org.flyware.util.page.PageUtil; .x1.` Y
tg7QX/KX
import com.adt.bo.Result; G$2Pny<!
import com.adt.dao.UserDAO; 9/{ 8Y&
import com.adt.exception.ObjectNotFoundException; A@e!~
import com.adt.service.UserManager; u/%Z0`X
h{^MdYJ
/** "g5MltH
* @author Joa NT{'BJ
*/ zKThM#.Wa
publicclass UserManagerImpl implements UserManager { #)4p,H
S~M/!Xb
private UserDAO userDAO; I(<Trn
'N`x@(
/** BwVq:)P/R
* @param userDAO The userDAO to set. vd/ BO
*/ @XVx{t;g2
publicvoid setUserDAO(UserDAO userDAO){ czK}F/Sg `
this.userDAO = userDAO; 7A{Z1[7
} f;!L\$yKy
HBA|NV3.
/* (non-Javadoc) sn+ kFvk}S
* @see com.adt.service.UserManager#listUser n!U1cB{
6n
H'NNS:J
(org.flyware.util.page.Page) w I[Hoi
V
*/ Nhtc^DX
public Result listUser(Page page)throws c_Iq!MH
~;uU{TT
HibernateException, ObjectNotFoundException { G6qFAepwi
int totalRecords = userDAO.getUserCount(); }S{VR(i`J
if(totalRecords == 0) lYU?j|n
throw new ObjectNotFoundException df/7u}>9
5kCXy$"%
("userNotExist"); nLR
page = PageUtil.createPage(page, totalRecords); %
@!hf!
List users = userDAO.getUserByPage(page); h<7@3Ur
returnnew Result(page, users); zrwzI+4
}
zuF]E+
Mtn{63cK
} uJa.]J~L=
<&HHo>rl
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ek d[|g
xu@xP5GB^
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 WA5.qw
wdIJ?\/763
询,接下来编写UserDAO的代码: rj/nn)vv;
3. UserDAO 和 UserDAOImpl: #;h>
x
java代码: f n8|@)J
Q)5V3Q]@^
TXqtE("BDl
/*Created on 2005-7-15*/ hJ?PV@xy
package com.adt.dao; XE#$|Z
H-eHX3c7
import java.util.List; )U{\c2b
hLT?aQLx
import org.flyware.util.page.Page; eL
[.;_
$ )6x3&]P
import net.sf.hibernate.HibernateException; 7_J0[C!G
L#fK
,r8
/** mNJCV8 <
* @author Joa 6UU<:KH
*/ C%#u2C2
publicinterface UserDAO extends BaseDAO { }4?z<. V
j%gle%_
publicList getUserByName(String name)throws - x; xQ
n^<J@uC
HibernateException; fM"&=X
bpa'`sf
publicint getUserCount()throws HibernateException; 6cOlY=
bn
m14'u GC
publicList getUserByPage(Page page)throws [{zfI`6
BY@l:y4
HibernateException; Yi <1z:\
Rpj{!Ia
} N9~'\O$'7
x#hSN|'"
s\Ln
/Eu|Jg=I
>uFFTik
java代码: p+-IvU
K1p. {
hRqr
/*Created on 2005-7-15*/ %8>0;ktU
package com.adt.dao.impl; s0DT1s&
'f8'|o)
import java.util.List; orAr3`AR3
c7nbHJi
import org.flyware.util.page.Page; LtV,djk
"d2JNFIHb
import net.sf.hibernate.HibernateException; ,lVQ-qw5
import net.sf.hibernate.Query; FJBB@<>:
csV3mzP
import com.adt.dao.UserDAO; -8v:eyc
{:=]J4]
/** H;#C NB<e
* @author Joa 6_K7!?YG7
*/ )!;20Po
public class UserDAOImpl extends BaseDAOHibernateImpl N|/gwcKe
%eGI]!vf
implements UserDAO { ?U
=Mdw
>?.jN|
/* (non-Javadoc) AuY*x;~
* @see com.adt.dao.UserDAO#getUserByName \uZ1Sl
f<y3/jl4
(java.lang.String) a3,A_M}M'
*/ z`,dEGfh^
publicList getUserByName(String name)throws j.c{%UYj
D'#,%4P,e\
HibernateException { 6NQ`IC
String querySentence = "FROM user in class @h(Z;
)_}xK={
com.adt.po.User WHERE user.name=:name"; 9<o*aFgCa
Query query = getSession().createQuery V7B%o:FZo
Bq,MTzxD
(querySentence); "*:?m{w5
query.setParameter("name", name); h<qi[d4X
return query.list(); kV4L4yE
} YD0j&@.
m%c]+Our`
/* (non-Javadoc) 5x!rT&!G
* @see com.adt.dao.UserDAO#getUserCount() yh'*eli
*/ (px3o'ls h
publicint getUserCount()throws HibernateException { ^2i$AM1t
int count = 0; AYDAt5K_
String querySentence = "SELECT count(*) FROM }|)T<|Y;
Hm+VGH'H?
user in class com.adt.po.User"; 2'Raj'2S4
Query query = getSession().createQuery %g69kizoWi
0a1Mu>P,
(querySentence); 0v``4z2Z
count = ((Integer)query.iterate().next fS p
2>f3nW
()).intValue(); X.ZG-TC
return count; iO$ ?No
} QHd|cg
=F_j})O5
/* (non-Javadoc) :d~mlyFI6P
* @see com.adt.dao.UserDAO#getUserByPage uc LDl
'C @yJf
(org.flyware.util.page.Page) =%|f-x
*/ ZA}!Rzo
publicList getUserByPage(Page page)throws U*XdFH}vV
($gmN 4
HibernateException { n^nQrRIp
String querySentence = "FROM user in class (%G>TV
_qH]OSo
com.adt.po.User"; B_C."{G
Query query = getSession().createQuery 0^6}s1d_
<SdOb#2
(querySentence); #c9MVQ_
query.setFirstResult(page.getBeginIndex()) ,^jQBD4={
.setMaxResults(page.getEveryPage()); 65tsJ"a<
return query.list(); >fD%lq;
} Ex6Kxd}8
%VE FruM
} <3Rq!w/
q(BRJ(
]deO\mB
OaY]}4tI$
3h6,x0AG
至此,一个完整的分页程序完成。前台的只需要调用 Jg$ NYs.xZ
TN/&^/
userManager.listUser(page)即可得到一个Page对象和结果集对象 /K;A bE
y^ D3}ds
的综合体,而传入的参数page对象则可以由前台传入,如果用 Z=l2Po n
WGo ryvEx
webwork,甚至可以直接在配置文件中指定。 ?P}) Qa
X>Z83qV5d!
下面给出一个webwork调用示例: I*pFX0+
java代码: 4-9cp=\PE
}a%Wu 7D
kmt+E'^]
/*Created on 2005-6-17*/ 4$4Tx9C
package com.adt.action.user; S+?*l4QK
fT=ZiHJ3Gu
import java.util.List; I/gfsyfA
7,Q7`}gBf
import org.apache.commons.logging.Log; |aj]]l[@S
import org.apache.commons.logging.LogFactory; H~:g=Zw
import org.flyware.util.page.Page; V'9OGn2v
j`_Z`eG
import com.adt.bo.Result; e.(RhajB
import com.adt.service.UserService; ~8'HX*B]z
import com.opensymphony.xwork.Action; !Wy&+H*0
mn(MgJKQ\
/** ANR611-a
* @author Joa [P]M)vJ**
*/ Q[lkhx|.B
publicclass ListUser implementsAction{ &m{~4]qWpM
#XNURj
privatestaticfinal Log logger = LogFactory.getLog bHzZ4i
"AIS6%,
(ListUser.class); d8WEsQ+)A
lxBcO/
private UserService userService; |r4&@)
,pW^>J
private Page page; {@Z*.G^
$$R->
privateList users; 8:]5H}Hi
r)<n)eXeD
/* syb$%
* (non-Javadoc) Q?'Ax"$D
* bf[l4$3k
* @see com.opensymphony.xwork.Action#execute() }@53*h i(
*/ |+=ctpx9&
publicString execute()throwsException{ o
Y<vKs^
Result result = userService.listUser(page); clr]gib
page = result.getPage(); Z
eWstw7
users = result.getContent(); D~TK'&