Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 XxeP;}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 QxbG-B^)=
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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 toU<InN
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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 YnU*MC}
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分页支持类: k|RY;
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java代码: wmX(%5vY^
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package com.javaeye.common.util; DTsD<o
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import java.util.List; 3&"uf9d
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publicclass PaginationSupport { 7/KK}\NE
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publicfinalstaticint PAGESIZE = 30; Kv:.bHN}
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privateint pageSize = PAGESIZE; .F%jbnKd_
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privateList items; A|4
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e NH9`Aa
privateint totalCount; #}Xsi&:XU
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privateint[] indexes = newint[0]; *2.h*y'u
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privateint startIndex = 0; u] G
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public PaginationSupport(List items, int r?
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totalCount){ 5-H"{29
setPageSize(PAGESIZE); j4`+RS+q
setTotalCount(totalCount); 9D,!]
setItems(items); j,9/eZRZ
setStartIndex(0); I (k(p\l%
} kaoiSL<[6
*5XOYb?'v.
public PaginationSupport(List items, int xDPR^xY
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totalCount, int startIndex){ UxF9Ko( ]d
setPageSize(PAGESIZE); sV0NDM0
setTotalCount(totalCount); 6Z=Qs=q
setItems(items); e_l|32#/
setStartIndex(startIndex); (!efaj
} >o3R~ [
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public PaginationSupport(List items, int }}rp/16
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totalCount, int pageSize, int startIndex){ tv~Y5e&8
setPageSize(pageSize); oxUBlye
setTotalCount(totalCount); py%~Qz%
setItems(items); eR`Q7]j] -
setStartIndex(startIndex); 48 0M|^
} amX1idHo^
&sYxe:H
publicList getItems(){ xTH3g^E
return items; }7xcHVO8-
} <dVJV?i;
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publicvoid setItems(List items){ M
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this.items = items; $Xu/P5
} J,=ZUh@M
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publicint getPageSize(){ 0S&J=2D!
return pageSize; mfffOG
} FJKlqM5]
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publicvoid setPageSize(int pageSize){ 0V8 6]zSo
this.pageSize = pageSize; paMK]-
} rz`"$g+#
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publicint getTotalCount(){ VfDa>zV3
return totalCount; zMO#CZ t
} ;|$o z{Ll
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publicvoid setTotalCount(int totalCount){ Hr7pcz/#l
if(totalCount > 0){ mb%U~Na
this.totalCount = totalCount;
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int count = totalCount / QoxQ"r9Wh
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pageSize; >vYb'%02
if(totalCount % pageSize > 0) u~JR]T
count++; a({N}ZDo
indexes = newint[count]; Ro `Xs.X
for(int i = 0; i < count; i++){ gq4X(rsyD
indexes = pageSize * ,&fZo9J9
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i; >#gDk K
} 1{a4zGE?[
}else{ p8?"}
this.totalCount = 0; nqTOAL9FF
} z[O*f#t
} vCK+v
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publicint[] getIndexes(){ a0 PU&o1EF
return indexes; ""_G4{
} .yD
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publicvoid setIndexes(int[] indexes){ hd(TKFL^y
this.indexes = indexes; !h<O c!9
} }s6Veosl
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publicint getStartIndex(){ OQKc_z'"
return startIndex; wa`c3PQGu
} >p;&AaXkoG
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publicvoid setStartIndex(int startIndex){ f|F=)tJO
if(totalCount <= 0) Q7d@+C
this.startIndex = 0; :)T*:51{#
elseif(startIndex >= totalCount) 7xux%:BN
this.startIndex = indexes A;&YPHB
?Pf#~U_
[indexes.length - 1]; c9c3o{(6Y
elseif(startIndex < 0) )~ &gBX
this.startIndex = 0; `CBXz!v!O
else{ o61rTj
this.startIndex = indexes fgC@(dvfk
:qj;f];|
[startIndex / pageSize]; YTTij|(
} G-R83Orl
} EwuRIe;D
/& c2y=/'C
publicint getNextIndex(){ loE;q}^
int nextIndex = getStartIndex() + esQ`6i
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pageSize; D@ !r?E`
if(nextIndex >= totalCount) _IV!9 JL
return getStartIndex(); DnG9bVm>
else z}Us+>z+jc
return nextIndex; #T{)y
} F+ RE
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publicint getPreviousIndex(){ '=\>n(%Q
int previousIndex = getStartIndex() - 2i
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pageSize; SXO.|"M
if(previousIndex < 0) cu'( Hj
return0; G)M! ,
Q
else o`7 Z<HF
return previousIndex; ZH>i2|W<
} T\=#y
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} ""|;5kJS4
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抽象业务类 ~Lg ;7i1L
java代码: 9k6/D.Dz
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/** YK$[)x\S
* Created on 2005-7-12 iVf7;M8O
*/ ~{-Ka>A
package com.javaeye.common.business; 3;wiwN'
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import java.io.Serializable; v ;Q*0%~
import java.util.List; ;(;~yB|NZ5
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import org.hibernate.Criteria; KhX)maQ
import org.hibernate.HibernateException; fE&s 6w&
import org.hibernate.Session; nt-_)4Fm
import org.hibernate.criterion.DetachedCriteria; r:E4Wi{\
import org.hibernate.criterion.Projections; P/^@t+KC
import 6BEpnw>p(
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org.springframework.orm.hibernate3.HibernateCallback; a\oz-`ESa
import |!7leL
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org.springframework.orm.hibernate3.support.HibernateDaoS suW|hh1/Ya
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upport; 7#oq|5
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import com.javaeye.common.util.PaginationSupport; 8O60pB;4
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public abstract class AbstractManager extends oSf`F1;)HQ
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HibernateDaoSupport { ],~[ ^0
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privateboolean cacheQueries = false; @g+v2(f2v
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privateString queryCacheRegion; &(l.jgqg&
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publicvoid setCacheQueries(boolean }Qe(6'l_
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cacheQueries){ XqhrQU|wM
this.cacheQueries = cacheQueries; P>)J:.tr0
} r!eW]M
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publicvoid setQueryCacheRegion(String m_Z(osoE#W
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queryCacheRegion){ 3O1Lv2)_
this.queryCacheRegion = 2EN}"Du]mj
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queryCacheRegion; I.|b:c
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} ,{msJyacmR
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publicvoid save(finalObject entity){ &m[}%e%~0
getHibernateTemplate().save(entity); !g}@xwWax
} |O'*CCrCL
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publicvoid persist(finalObject entity){ tq@)J_7|
getHibernateTemplate().save(entity); e Y^zs0
} -%P}LaC<
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publicvoid update(finalObject entity){ J(maJuY
getHibernateTemplate().update(entity); y;4g>ma0
} 3
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publicvoid delete(finalObject entity){ +Zr~mwM=x
getHibernateTemplate().delete(entity); 4KSq]S.
} :[f[-F
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publicObject load(finalClass entity, !+z^VcV
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finalSerializable id){ )+8r$ i
return getHibernateTemplate().load #Dz"g_d
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(entity, id);
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} V*(x@pF
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publicObject get(finalClass entity, m^m=/'<+
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finalSerializable id){ n+Conp/
return getHibernateTemplate().get 9mv0} I
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(entity, id); :V#xrH8R
} omy3<6
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publicList findAll(finalClass entity){ 99By.+~pX
return getHibernateTemplate().find("from O0`ofFN
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ss
" + entity.getName()); 5rCJIl.
} f?GoBh<
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publicList findByNamedQuery(finalString i[FYR;C
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namedQuery){ y:$qX*+9e
return getHibernateTemplate 9,\AAISi
q+<,FdG
().findByNamedQuery(namedQuery);
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} r2i]9>w
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publicList findByNamedQuery(finalString query, J&JZYuuf
@W
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finalObject parameter){ zw$\d1-+h
return getHibernateTemplate mJ5%+.V
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().findByNamedQuery(query, parameter); Knb(MI6
} b2[U3)|oO
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publicList findByNamedQuery(finalString query, IuAu_`,Ndi
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finalObject[] parameters){ PU1YR;[Fe
return getHibernateTemplate F6Q%<p a
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().findByNamedQuery(query, parameters); K]M@t=
} /?XI,#j3kM
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publicList find(finalString query){ h&d"| <
return getHibernateTemplate().find gp $Rf9\
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(query); u(f;4`
} +|pYu<OY
gae=+@z
publicList find(finalString query, finalObject 5T( cy
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parameter){ ZHeq)5C ;f
return getHibernateTemplate().find ;/?w-)n?
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(query, parameter); 4t/ ?b
} 8)pL0bg
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@V4
public PaginationSupport findPageByCriteria \.sC{@5K
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(final DetachedCriteria detachedCriteria){ e 6>j
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return findPageByCriteria ^*B@=
X !0 7QKs
(detachedCriteria, PaginationSupport.PAGESIZE, 0); F Qk
} S'ms>ZENC
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public PaginationSupport findPageByCriteria >py[g0J
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(final DetachedCriteria detachedCriteria, finalint RIO?rt;
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startIndex){ VGxab;#,:3
return findPageByCriteria .j|uf[?h
/Qef[$!(
(detachedCriteria, PaginationSupport.PAGESIZE, .Z"`:4O
/4;A.r`;
startIndex); I2SH
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} o&z [d
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public PaginationSupport findPageByCriteria em )%U
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(final DetachedCriteria detachedCriteria, finalint U,6sR
,`YBTU
pageSize, \QF0(*!!
finalint startIndex){ D Y4!RjJ47
return(PaginationSupport) Gx}`_[-
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getHibernateTemplate().execute(new HibernateCallback(){ &V+KM"Ow
publicObject doInHibernate T9]0/>
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(Session session)throws HibernateException { GJ2ZK=/
Criteria criteria = /'_<~A
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detachedCriteria.getExecutableCriteria(session); _JTK$\
int totalCount = (aSuxl.Dq
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((Integer) criteria.setProjection(Projections.rowCount K`<HZK
Pi9?l>
()).uniqueResult()).intValue(); wpi$-i`
criteria.setProjection P6ktA-Hv>
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(null); 4(oU88z
List items = Fo;:GX,b
>#l:]T
criteria.setFirstResult(startIndex).setMaxResults S+-$Ih`[
=h|cs{eT\2
(pageSize).list(); Zby3.=.e
PaginationSupport ps = CQa8I2VF
(
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new PaginationSupport(items, totalCount, pageSize, .sM,U
x{K"z4xbI
startIndex);
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return ps; IO=$+c
} $_TS]~y4}
}, true); UF }[%Sa
} =2QP7W3mg<
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public List findAllByCriteria(final 9y5JV3
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DetachedCriteria detachedCriteria){ PeqW+Q.
return(List) getHibernateTemplate 3tJfh=r=1
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().execute(new HibernateCallback(){ !.t D.(XP
publicObject doInHibernate 74:~F)BP
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(Session session)throws HibernateException { 3"v>y]$U
Criteria criteria = ']I!1>v$[
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detachedCriteria.getExecutableCriteria(session); _-543B}
return criteria.list(); p[].4_B;
} }mIN)o
}, true); &IzNoB
} w3sU& |N
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public int getCountByCriteria(final *x]*%
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DetachedCriteria detachedCriteria){ xLi3|^q
Integer count = (Integer) n=F
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getHibernateTemplate().execute(new HibernateCallback(){ Xy!NBh7I
publicObject doInHibernate V.qH&FJ=l
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(Session session)throws HibernateException { r<:d+5"
Criteria criteria = @H4]Gp ]
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detachedCriteria.getExecutableCriteria(session); eiyr^Sch.
return GI,TE
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criteria.setProjection(Projections.rowCount jn(!6\n"
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()).uniqueResult(); YaC[S^p
} <DR!AR)
}, true); _Y]Oloo('
return count.intValue(); Cojs;`3iF:
} t^zE^:06
} ^dhx/e%s
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用户在web层构造查询条件detachedCriteria,和可选的 <; ?1#ok
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 U!uJ )mm
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PaginationSupport的实例ps。 ~|O; Sdo=
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ps.getItems()得到已分页好的结果集 9*K-d'm
ps.getIndexes()得到分页索引的数组 ^--R#$X
ps.getTotalCount()得到总结果数 cb0rkmO
ps.getStartIndex()当前分页索引 Ay 4P_>^
ps.getNextIndex()下一页索引 !m9hL>5vR
ps.getPreviousIndex()上一页索引 rEC
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 IO
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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 'kC#GTZi
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一下代码重构了。 phf{b+'#X
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我把原本我的做法也提供出来供大家讨论吧: ZX`x9/0&
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首先,为了实现分页查询,我封装了一个Page类: w6X:39d
java代码: 4^:dmeMZ`
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/*Created on 2005-4-14*/ 1hi,&h
package org.flyware.util.page; /}6y\3h
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/** G/#<d-}_
* @author Joa [f lK
* $/g`{OI]K
*/ G<<;a
publicclass Page { >]gB@tn[
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/** imply if the page has previous page */
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privateboolean hasPrePage; H!X*29nX
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lu?
/** imply if the page has next page */ HpIi- Es7C
privateboolean hasNextPage; ILH[q>
5EI"5&`*
/** the number of every page */ Yu_
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privateint everyPage; (2L,m
C(B"@
/** the total page number */ Q$]1juqg
privateint totalPage; GBRiU&D
/|UbYe,
/** the number of current page */ B]<N7NYn1
privateint currentPage; =FIZh}JD
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/** the begin index of the records by the current u1u;aG
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query */ SnXM`v,
privateint beginIndex; 1D8S}=5&
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/** The default constructor */ O NcLhwH
public Page(){ _ eBNbO_J
JLo E)\Mi
} R[v<mo[s
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/** construct the page by everyPage K8BlEF`
* @param everyPage Je9Z:s[
* */
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public Page(int everyPage){ F-ofR]|)>
this.everyPage = everyPage; 8,vP']4r%
} _4SZ9yu
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/** The whole constructor */ r1RM7y
public Page(boolean hasPrePage, boolean hasNextPage, 2h*aWBLk
)T
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int everyPage, int totalPage, VZ`YbY
int currentPage, int beginIndex){ tS3&&t
this.hasPrePage = hasPrePage; I/A%3i=H
this.hasNextPage = hasNextPage; g5Io=e@s
this.everyPage = everyPage; uTrzC+\aU
this.totalPage = totalPage; }{:}K<
this.currentPage = currentPage; /`aPV"$M
this.beginIndex = beginIndex; Lwf[*n d
} '" &*7)+g*
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/** o(l%k},a
* @return V62lN<M
* Returns the beginIndex. (]I=';\
*/ Wrp+B[{r\
publicint getBeginIndex(){ r]D>p&4
return beginIndex; }u0&> k|y
} fiSX( 9
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/** WpE"A
* @param beginIndex Xf7]+
* The beginIndex to set. nC??exc
*/ eUCBQK
publicvoid setBeginIndex(int beginIndex){ 7iM@BeIf
this.beginIndex = beginIndex; Q$`uZ
} BSd.7W;cS=
_G<Wq`0w)
/** G}NqVbZ9]
* @return ><S2o%u~
* Returns the currentPage. 5pY|RV6:
*/ DQV9=
publicint getCurrentPage(){ &1yErGXC
return currentPage; -:45Q{u/
} ^
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/** jHatUez4O
* @param currentPage v<l]K$5J&
* The currentPage to set. AFYdBK]
*/ ]S9Z5l0
publicvoid setCurrentPage(int currentPage){ Ow5VBw(
this.currentPage = currentPage; UMD\n<+cG,
} =<aFkBX-
u=~`5vA
/** !e
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* @return |<oqT+?i
* Returns the everyPage. x.|sCqx
*/ OR+py.vK
publicint getEveryPage(){ awQGu,<N
return everyPage; z `\KQx
} W[Z[o+7pK
t*Z5{
/** FBouXu#
* @param everyPage E|_8#xvb
* The everyPage to set. c`lL&*]
*/ /FPO'} 6i
publicvoid setEveryPage(int everyPage){ [GI2%uA0
this.everyPage = everyPage; sVmqx^-
} {dE(.Z?]!#
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/** +tg${3ti_
* @return $X\2h+ Os
* Returns the hasNextPage. zO$r
*/ 'T7 3V
publicboolean getHasNextPage(){ >MRuoJ
return hasNextPage; r_tt~|s,>
}
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/** }jWg&<5+z
* @param hasNextPage M5_t#[ [
* The hasNextPage to set. i=P}i8,^=
*/ THK^u+~LM
publicvoid setHasNextPage(boolean hasNextPage){ *a{WJbau]
this.hasNextPage = hasNextPage; /!p}H'jl
} f;,*P,K
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/** f$dIPt(
* @return #a
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* Returns the hasPrePage. )_o^d>$da
*/ ? `kZ 6$
publicboolean getHasPrePage(){ ;}ThBb3
return hasPrePage; Wy/h"R\=
} ]8Xip/uE
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/** Ja/
* @param hasPrePage `@:TS)6X0
* The hasPrePage to set. TpYh)=;k
*/ Pl`Nniy
publicvoid setHasPrePage(boolean hasPrePage){ UL%a^' hR
this.hasPrePage = hasPrePage; {9XNh[NbP
} Co=Bq{GY
]TcQGW@'
/** |}<Gz+E>
* @return Returns the totalPage. ]P>XXE;[
* !3DY#
*/ 0O]v|
publicint getTotalPage(){ AA=eWg
return totalPage; Ra
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} AUIp
vd
/J&DYxl":
/** DpT$19Q+
* @param totalPage ^7=7V0>,:
* The totalPage to set. )DlKeiK
*/ fd>&RbUp
publicvoid setTotalPage(int totalPage){ )t\aB_ =
this.totalPage = totalPage; n;>=QG
-v
} vEGI
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} {c*5 )x!
l5KO_"hy
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u3tT=5.D
ev_' .t'
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 vP? T
;G3?Sa7+
个PageUtil,负责对Page对象进行构造: x)eoz2E1
java代码: 8gt&*;'}*D
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wQ@:0GJH
/*Created on 2005-4-14*/ D&~%w!
package org.flyware.util.page; V@O)7ND
6h %rt]g
import org.apache.commons.logging.Log; !H9^j6|
import org.apache.commons.logging.LogFactory; *vvm8ik
d~{$,"!-f
/** KNj~7aTp
* @author Joa
j|!t3}((
* f:J-X~T_f
*/ K'
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publicclass PageUtil { ]6A wd A
p?4[nS-,
privatestaticfinal Log logger = LogFactory.getLog t*)mX2R,
A=p'`]Yld
(PageUtil.class); =oI6yf&8 Z
u*,>$(-u
/** 10OkrNQ
* Use the origin page to create a new page N3@[95
* @param page kLU-4W5t
* @param totalRecords t4/ye>P &
* @return 0(:SEiz6s
*/ c-n/E. E
publicstatic Page createPage(Page page, int 0\B{~1(^
+8itP>
totalRecords){ %d(= >
return createPage(page.getEveryPage(), `.3@Ki~$#
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page.getCurrentPage(), totalRecords); 5$N#=i`V
} iR88L&U>
%9Z0\
a)[
/** bcpsjUiy#
* the basic page utils not including exception 6y MZ2%
NRp
handler pi/0~ke4"
* @param everyPage x|G
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* @param currentPage \]5I atli
* @param totalRecords QKlsBq
* @return page 2{vAs
*/ 0< vJ*z|_
publicstatic Page createPage(int everyPage, int >0<n%V#s:r
ih^FH>@
currentPage, int totalRecords){ A8Fe@$<#8
everyPage = getEveryPage(everyPage);
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currentPage = getCurrentPage(currentPage); W{tZX^|
int beginIndex = getBeginIndex(everyPage, GQ7uxdqWBQ
=W:=}ODD
currentPage); rVl 8?uy
int totalPage = getTotalPage(everyPage, mTxqcQc:7
m|{^T/kIbQ
totalRecords); 2b^Fz0
w4
boolean hasNextPage = hasNextPage(currentPage, :/$WeAg
liH#=C8l*%
totalPage); X~D[CwA|`
boolean hasPrePage = hasPrePage(currentPage); t&J A1|q
83t/\x,Q
returnnew Page(hasPrePage, hasNextPage, 'hs4k|B
everyPage, totalPage, HdB>CVuh
currentPage, Q!V:=d
*K;)~@n
beginIndex); 5:f!EMb
} 2HN*j~>i~
yxp,)os:
privatestaticint getEveryPage(int everyPage){ Hxgc9Fis
return everyPage == 0 ? 10 : everyPage; d!0rq4v7
} D_czUM
UgS`{&b36
privatestaticint getCurrentPage(int currentPage){ ?dCwo;~
return currentPage == 0 ? 1 : currentPage; 2J&~b 8 :
} "YgpgW
Y'iyfnk
privatestaticint getBeginIndex(int everyPage, int 52tc|j6~#
:e;6oC*"q
currentPage){ T[k$ [
return(currentPage - 1) * everyPage; kF~(B]W(
} 6` TwP\!$/
cVL|kYVWT
privatestaticint getTotalPage(int everyPage, int "}*D,[C5e
J~]@#=,v
totalRecords){ 8lYA6A
int totalPage = 0; Rq5'=L
5buW\_G)
if(totalRecords % everyPage == 0) U\?D;ABQ%
totalPage = totalRecords / everyPage; 2RX]~}
else uo]xC+^
totalPage = totalRecords / everyPage + 1 ; ya8p
4N{_
X_o#!
return totalPage; <Q9l'u]3$c
} D`a6D
|du%c`wl
privatestaticboolean hasPrePage(int currentPage){ y&,|+h
return currentPage == 1 ? false : true; O?Bf (y
} :.e'?a
?o;ip
privatestaticboolean hasNextPage(int currentPage, hFi gY\$m
[8sYE h
int totalPage){ %%s)D4sW
return currentPage == totalPage || totalPage == Ol RXgJ
3d6z_Yd:
0 ? false : true; ?Te#lp;`~
} s"=TM$Vb
F%|P#CaB
X+XDfEt:Q
} ;um)JCXz
<
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HqW /
,XEIg
>fXtu:C-!J
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 6~%><C
Ra|P5
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 D#&9zR86F
#kM|!U=
做法如下: =\%ER/
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 AyO%,6p[
6
H P66B
的信息,和一个结果集List: b_~XTWP$l
java代码: GB|>eZLv<
~ps,U
y<FC7
/*Created on 2005-6-13*/ (uvQ/!
package com.adt.bo; U_*,XLU
T$D(Y`zdn
import java.util.List; D0jV}oz
"Wg,]$IvU
import org.flyware.util.page.Page; ruGJZAhIA^
-orRmn6}
/** + kKanm[!v
* @author Joa 1@L18%h
*/ }?,?2U,8:
publicclass Result { EN2t}rua
\PxT47[@e
private Page page; [y9a.*]u/@
}"T Q\v$
private List content; l%EvXdZuOy
Wm6qy6HR
/** GmR3
a
* The default constructor H7tviSTd
*/ s<{ Hu0K$
public Result(){ X=#us7W}
super(); m:h6J''<Z*
} BEaF-*?A
nv_v FK
/** $!*>5".A
* The constructor using fields 9s"st\u
4
* v%qOW)].
* @param page I/njyV)H
* @param content \~*<[.8~
*/ 9PKXQp
public Result(Page page, List content){ F~6]II
this.page = page; @\&j3A
this.content = content; rByth,|
} F NPu
[<53_2]~
/** G~5pMyOR
* @return Returns the content. V#w$|2
*/ INr1bAe$
publicList getContent(){ $Lj]NtO
return content; SvSO?H!-
} #1haq[Uv7
N]
sbI)Z@
/** vm|u~Yd,s
* @return Returns the page. `6VnL)
*/ A:(|"<lA
public Page getPage(){ P6GTgQ<'BA
return page; cIw X sx
} .9vS4C
A.r7 ks
/** <CVX[R]U
* @param content Jt5V{9:('
* The content to set. "yw{A%J
*/ [`GSc6j
public void setContent(List content){ {'4#{zmp
this.content = content; &5-1Cd E
} v,}C~L3
i$] :Y`3h
/** nZB~l=
* @param page Trs~KcsD
* The page to set. W~mo*EJ'^
*/ )(G<(eiD
publicvoid setPage(Page page){ @LI;q
this.page = page; l!:bNMd
} 6 EqN>.
} dQIF'==6
7#C$}1XJ1
:-d#kU
T@ESMPeU:X
5Yv*f:
2. 编写业务逻辑接口,并实现它(UserManager, AVjRhe
MPUyu(-%{
UserManagerImpl) b<y*:(:
java代码: '|]}f }Go
Xi"9y @
}T.>p#z
/*Created on 2005-7-15*/ p|-> z
package com.adt.service; B`QF;,3S
+>C26Q
import net.sf.hibernate.HibernateException; H&ek"nP_
o+hp#e
import org.flyware.util.page.Page; dE8f?L'
O;4S<N
import com.adt.bo.Result; SHYekX
:i>LESJq
/** ]7<$1ta
* @author Joa ?:/J8s
[O
*/ s;P _LaIp)
publicinterface UserManager { |rJN
^?fsJ
public Result listUser(Page page)throws U $#^ e
Po=:-Of:
HibernateException; x(u.(:V
agfDx^,
} (zsmJe
8-+# !]
H%n/;DW
0(c,J$I]Z!
*H/)S 5
java代码: NUnwf
h
I;jH'._k#
0UpRSh)#
/*Created on 2005-7-15*/ JGq9RB]D$
package com.adt.service.impl; ([$KXfAi]h
X_-/j.
import java.util.List; ]NaH *\q
y+B iaD!U
import net.sf.hibernate.HibernateException; ){/n7*#Th%
v89tV9O)
import org.flyware.util.page.Page; |7|'JTy
import org.flyware.util.page.PageUtil; M GC=L .
?_{{iil
import com.adt.bo.Result; vB7]L9=@"
import com.adt.dao.UserDAO; Se??E+aX
import com.adt.exception.ObjectNotFoundException; lz0dt<8eP
import com.adt.service.UserManager; g#{7qmM
-"Kjn`8
/** /FXb,)1t
* @author Joa /!&eP3^
*/ 0@'-g^PS
publicclass UserManagerImpl implements UserManager { M&Q&be84
hT=E~|O
private UserDAO userDAO; FFwu$S6e
Q.4+"JoG
/** ^,'KmZm=
* @param userDAO The userDAO to set. G|&$/]~
*/ 2bXCFv7}
publicvoid setUserDAO(UserDAO userDAO){ #m7evb5eg*
this.userDAO = userDAO; t:.X=/02
} l;z+E_sQ
,UVd+rY}
/* (non-Javadoc) Tpnwwx[]:|
* @see com.adt.service.UserManager#listUser N}z]OvnZH
yYJ +vs
(org.flyware.util.page.Page) :q1j?0{2N
*/ s*CBYzOm
public Result listUser(Page page)throws t P'._0n0
5 a&a-(
HibernateException, ObjectNotFoundException { S2I{?y&K
int totalRecords = userDAO.getUserCount(); 4tiCxf)
if(totalRecords == 0) nm|"9|/
throw new ObjectNotFoundException v~^*L iP+
ayf;'1
("userNotExist"); 3gCP?%R
page = PageUtil.createPage(page, totalRecords); )1 0aDTlr
List users = userDAO.getUserByPage(page); Fvv/#V^R
returnnew Result(page, users); =6'D/| 3
} jfR!M07|
>\Iy <M
} O,&p"K&Z
BYI13jMH+Y
8
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dr=KoAIxy
r)w]~)8
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 lt l(SIi
(j)>npOd9
询,接下来编写UserDAO的代码: "Bn]-o|r
3. UserDAO 和 UserDAOImpl: FbPoyh
java代码: ~:4Mf/Ca
Y,%G5X@S<
{M0pq3SL*t
/*Created on 2005-7-15*/ &2Cu"O'.i
package com.adt.dao; rI]n4>k{
_@]@&^K$E
import java.util.List; yc$8X sns
5~omZ,qe
import org.flyware.util.page.Page; {uO2m*JrI
L_YY,
import net.sf.hibernate.HibernateException; WB|SXto%4D
CY8=prC
/** "j+=py`
* @author Joa 9y"\]G77E
*/ +(2mHS0_a
publicinterface UserDAO extends BaseDAO { _i&awm/U
SJI+$L\'
publicList getUserByName(String name)throws d,).O
852Bh'u_
HibernateException; =kWm9W<^
Y'i_EX|
publicint getUserCount()throws HibernateException; RiAY>:
wkZ}o,{*:
publicList getUserByPage(Page page)throws DadlCEZv
9k!#5_ M
HibernateException; 8|p*T&Cn&
!xh.S#B
} TL_8c][.4$
JS1''^G&.
j'JNQo;q
fqU*y 6]
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java代码: }Pe0zx.Ge
k@ZmI^
/\M3O
/*Created on 2005-7-15*/ snyg
package com.adt.dao.impl; Obu>xK(
kC)ye"r
import java.util.List; 3 aG?^z
vL7JzSU_
import org.flyware.util.page.Page; H{CG/+x
"(rG5z3P
import net.sf.hibernate.HibernateException; ajz%3/R
import net.sf.hibernate.Query; L?e N(L
thjCfP
import com.adt.dao.UserDAO; `PR)7}/<
@bj3N
/** !bG%@{W T
* @author Joa O=PyXOf
*/ jn9KQe\3
public class UserDAOImpl extends BaseDAOHibernateImpl e " f/
s`G3SE
implements UserDAO { EsU-Ckb_2:
"?GA}e"R
/* (non-Javadoc) 4b B)t#
* @see com.adt.dao.UserDAO#getUserByName Ul@yXtj
195m0'zda
(java.lang.String) fE;<)tU
*/ {WJ+6!v
publicList getUserByName(String name)throws ~P85Or
pAo5c4y!4
HibernateException { <m#ov G6
String querySentence = "FROM user in class V3NQij(
Vs)Pg\B?
com.adt.po.User WHERE user.name=:name"; E
hROd
Query query = getSession().createQuery tN=B9bm3j
{f\/2k3
(querySentence); _>8ZL)NQQ
query.setParameter("name", name); MV<2x7S
return query.list(); P"LbWZ6Nj
} QQUYWC
9"3 7va
/* (non-Javadoc) lU0'5!3R,
* @see com.adt.dao.UserDAO#getUserCount() \ s8j*
*/ )B86
publicint getUserCount()throws HibernateException { xG JX~)
int count = 0; RjY(MSc
String querySentence = "SELECT count(*) FROM F/FUKXxx
gwj+~vSfi
user in class com.adt.po.User"; oz(V a!
Query query = getSession().createQuery HrH-e=j
<
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(querySentence); A~_*vcz
count = ((Integer)query.iterate().next ]uN}n;`12
(*>%^ C?
()).intValue(); Tji G!W8
return count; ~ [k0ay
} | N%?7PZ(
8X,dVX5LT
/* (non-Javadoc) LD]a!eY
* @see com.adt.dao.UserDAO#getUserByPage B8){
#1-,s.)
(org.flyware.util.page.Page) b*w@kLLN
*/ v803@9@
publicList getUserByPage(Page page)throws + niz(]
^=f<WKn
HibernateException { .gL%0
String querySentence = "FROM user in class F7!g+LPc<
s&UuB1
com.adt.po.User"; '
U]\]Wp
Query query = getSession().createQuery $on"@l%U
.E H&GX
(querySentence); }^!8I7J.
query.setFirstResult(page.getBeginIndex()) #aX+?z\4
.setMaxResults(page.getEveryPage()); vS#Y,H:yAj
return query.list(); 1>I4=mj
} c2Q KI~\x
e[<vVe!
} 6#[
00jW s@K
V
iY -&q'
%b8ig1
05o)Q &`
至此,一个完整的分页程序完成。前台的只需要调用 0 &M~lJ
+rAmy
userManager.listUser(page)即可得到一个Page对象和结果集对象 '%Cc!63t*
bTBV:]w
的综合体,而传入的参数page对象则可以由前台传入,如果用 2/Xro rV
j) G<PW
webwork,甚至可以直接在配置文件中指定。 \wMqVRPoQ
6pJFrWe{
下面给出一个webwork调用示例: E}?n^Zf
java代码: /g/]Q^
J,iS<lV_
'e&L53n
/*Created on 2005-6-17*/ <}uhKp>*
package com.adt.action.user; 0m2%ucKw
N>pTl$\4
import java.util.List; QZwUv<*
olm0O (9
import org.apache.commons.logging.Log; #VM+.75o1
import org.apache.commons.logging.LogFactory; o >wty3l:
import org.flyware.util.page.Page; `!,"">5
>m:;.vVY
import com.adt.bo.Result; k)j6rU
import com.adt.service.UserService; u[:-^H
import com.opensymphony.xwork.Action; Nm{+!}cC
U/}("i![Dy
/** NL^;C3u
* @author Joa ~ 3!yd0[k
*/ #%9t-
publicclass ListUser implementsAction{ WswM5RN
^X]rFY1
privatestaticfinal Log logger = LogFactory.getLog $^TxLv
%I^schE*
(ListUser.class); /1y\EEc
KPi_<LuK
private UserService userService; a!@(bb
z>
nyoLrTs{
private Page page; }HCt=W`
tZXq<k9
privateList users; I]@QhCm0
l;;,[xhq
/* 9kzJ5}
* (non-Javadoc) awU!3)B
* c)j60y
* @see com.opensymphony.xwork.Action#execute() u+;iR/
*/ ul-O3]\'@
publicString execute()throwsException{ \? n<UsI
Result result = userService.listUser(page); 6:Hd `
page = result.getPage(); oA* 88c+{f
users = result.getContent(); " k0gZb
return SUCCESS; f8?hEa:js
} o$p]
p9
*ZkOZ
/** Z!+n/ D-1
* @return Returns the page. "8$Muwm
*/ J4]tT pu"K
public Page getPage(){ 5E#8F
return page; 0 wjL=]X1e
} a9uMgx}
?!.L#]23f
/** /pC60y}O0
* @return Returns the users. $ghlrV;:ct
*/ gXj3=N(l
publicList getUsers(){ Xf;_r+;
return users; &s{d r
} ?>1wZ
c;,-I
/** 2U`!0~pod
* @param page mKLWz1GZ
* The page to set. rA|&G'
*/ #~o<9O
publicvoid setPage(Page page){ '=+gweM
this.page = page;
6o1[fr
} U]&/F{3
im
8{
+KNqz
/** )43z(:<
* @param users ~J0r%P
* The users to set. }ww`Y
*/ BS2'BS8
publicvoid setUsers(List users){ dG!) <
this.users = users; \8)FVpS
} R_=fH\c;
OD~yIV
/** CHVAs9mrNB
* @param userService 1 XpqnyL&
* The userService to set. BQ=JZ4&
*/ "[sr0'g:
publicvoid setUserService(UserService userService){ B@ >t$jK
this.userService = userService; ,va2:V
} RS|*3
$1
} Jv8VM\*
Z6nQW53-
.dn#TtQv
E_0i9
/A-VT
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, YlXqj\a
/GF"D5
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ]l"9B'XR
w3;T]R*
么只需要: S
rhBU6K
java代码: Of-8n-
zj$Ve
8g?2( MT;
<?xml version="1.0"?> R ^"*ut
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork a :CeI
Pk6_ 1LV
1.0//EN" "http://www.opensymphony.com/xwork/xwork- R8Dn
GR
u63Q<P<