Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 y{&k`H
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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 m7<HK,d
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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 %>,B1nt
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分页支持类: I+JWDYk
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java代码: yf|,/{S
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package com.javaeye.common.util; \.0cA4)[$
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import java.util.List; $H0diwl9R
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publicclass PaginationSupport { GCrIaZ
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publicfinalstaticint PAGESIZE = 30; 3C:!\R
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privateint pageSize = PAGESIZE; XOOWrK7O
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privateList items; M.DU^-7
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privateint totalCount; cL+--$L
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privateint[] indexes = newint[0];
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privateint startIndex = 0; tKr.{#)
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public PaginationSupport(List items, int g(X-]/C{
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totalCount){ t1LIZ5JY
setPageSize(PAGESIZE); =1!,A
setTotalCount(totalCount); \VL_
setItems(items); `
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setStartIndex(0); CsJ38]=Mt
} 6CQ.>M:R
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public PaginationSupport(List items, int "o| f
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totalCount, int startIndex){ W|~Jl7hs8Q
setPageSize(PAGESIZE); ;HKb
setTotalCount(totalCount); 4blw9x N
setItems(items); It5U=PU
setStartIndex(startIndex); )^Ha?;TS
} iTX:*$~I
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public PaginationSupport(List items, int tVAWc$3T
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totalCount, int pageSize, int startIndex){ h;q=<[h\
setPageSize(pageSize); .,-,@ZK
setTotalCount(totalCount); .2K4<UOAbm
setItems(items); a'NxsByG]s
setStartIndex(startIndex); \IL;}D{
} B #[URZ9S
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publicList getItems(){ SHoov
return items; su?{Cj6*
} jb~W(8cj
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publicvoid setItems(List items){ mbf'xGO
this.items = items; ;-aF\}D@n
} /]xu=q2
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publicint getPageSize(){ )+Nm@+B
return pageSize; }Q }&3m~g
} 0XkLWl|k
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publicvoid setPageSize(int pageSize){ zC@ ziH>{]
this.pageSize = pageSize; 4t C-msTf
} A-=B#U F
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publicint getTotalCount(){ /mi9q
return totalCount; \2UtT@3|C
} r>>4)<C7J
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publicvoid setTotalCount(int totalCount){ n]G_#
;
if(totalCount > 0){ f *Xum[
this.totalCount = totalCount; /.knZ_aJ!
int count = totalCount / 6%jv|\>
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pageSize; {Df97n%h;
if(totalCount % pageSize > 0) ;)6LX-
count++; T(GEFntY
indexes = newint[count]; %=ZN2)7{
for(int i = 0; i < count; i++){ .=~-sj@k
indexes = pageSize * qD/GYqvm
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i; fXL&?~fS
} "8.to=Lx
}else{ _f"HUKGN
this.totalCount = 0; /~8<;N>,+
} aEO`` W
} QNN*/n
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publicint[] getIndexes(){ ?g~w6|U(r
return indexes; v$WH#;(\
} 8\AyKw
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publicvoid setIndexes(int[] indexes){ jX9{Ki"
this.indexes = indexes; +vDEDOS1
} +#B4Z'nT
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publicint getStartIndex(){ Qb N7sg~~
return startIndex; slQxz;t
} tny^sG/'
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publicvoid setStartIndex(int startIndex){ \!*3bR
if(totalCount <= 0) 0xN1Xm0d
this.startIndex = 0; u{asKUce\
elseif(startIndex >= totalCount) 6\+ZTw
this.startIndex = indexes jD<fu
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[indexes.length - 1]; %Voq"}}N
elseif(startIndex < 0) Y=NXfTc
this.startIndex = 0; 0P+B-K>n
else{ l[,RA?i
{
this.startIndex = indexes `<?{%ja
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[startIndex / pageSize]; o4[
} +zl2|'
} h/LlH9S:!
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publicint getNextIndex(){ <FkoWN
int nextIndex = getStartIndex() + @nh*H{
z PW [GkD
pageSize; 7_=7 ;PQ<
if(nextIndex >= totalCount) Ar;uq7c,G
return getStartIndex(); q2$-U&
else ]_hrYjX;
return nextIndex; sy\w ^]
} wU"0@^k]<
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publicint getPreviousIndex(){ ~!Ar`=
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int previousIndex = getStartIndex() - o 94]:$=~
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pageSize; ,GU|3
if(previousIndex < 0) un&Z'
.
return0; (
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else 'XbrO|%
return previousIndex; >u-6,[(5X*
} I6.!0.G
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} I7S#vIMXR.
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抽象业务类 yF _@^V
java代码: C.#\Pz0
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/** z_ 01*O
* Created on 2005-7-12 YF4?3K0F:k
*/ #s}cK
package com.javaeye.common.business; {hNvCk
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import java.io.Serializable;
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import java.util.List; 4/Mi-ls_
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import org.hibernate.Criteria; 1KI,/ H"SY
import org.hibernate.HibernateException; )' hOW*v
import org.hibernate.Session; Q4[^JQsR2
import org.hibernate.criterion.DetachedCriteria; 3jh:
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import org.hibernate.criterion.Projections; ;1^([>|
import O} &%R:
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org.springframework.orm.hibernate3.HibernateCallback; D,c53B6M
import 'G#T 6B!
^p}S5,
org.springframework.orm.hibernate3.support.HibernateDaoS drM@6$k
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upport; ^z^zsNx
} 5nVZ;
import com.javaeye.common.util.PaginationSupport; 7gx
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public abstract class AbstractManager extends P@xb
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HibernateDaoSupport { c@&`!e
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privateboolean cacheQueries = false; HT%
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privateString queryCacheRegion; B(zcoWQ*B
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publicvoid setCacheQueries(boolean Rn4Bl8z'>
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cacheQueries){ ?b,x;hIO
this.cacheQueries = cacheQueries; jfOqE*frl!
} KT9!R
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publicvoid setQueryCacheRegion(String ^tr?y??k
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queryCacheRegion){ HO`N]AMw
this.queryCacheRegion = CC~:z/4,N
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queryCacheRegion; en?J#fz
} c?/R=/H
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publicvoid save(finalObject entity){ !4 =]@eFk
getHibernateTemplate().save(entity); e*Gt%'
} 2K~<_.S
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publicvoid persist(finalObject entity){ AY
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getHibernateTemplate().save(entity); iL6Yk @
} ,P.yl~'Al
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publicvoid update(finalObject entity){ Af`qe+0E
getHibernateTemplate().update(entity); 6`JY:~V"
} c2o.H!>
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publicvoid delete(finalObject entity){ %p(!7FDE2n
getHibernateTemplate().delete(entity); ~M!9E])
} Y;uQq-C P
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publicObject load(finalClass entity, Mnx')([;W
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finalSerializable id){ NU <K+k
return getHibernateTemplate().load .IkQo`_s:
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(entity, id); 'Y;M%
} 5X1z^(
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publicObject get(finalClass entity, u;/5@ADW
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finalSerializable id){ @}oY6cW;B*
return getHibernateTemplate().get %vZTD+i
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(entity, id); GLpl
} WW&agr
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publicList findAll(finalClass entity){ QO;OeMQv%
return getHibernateTemplate().find("from #<k L.e[
G<_<j}=
" + entity.getName()); |H%[tkW6c
} \v]esIP5R'
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publicList findByNamedQuery(finalString iS@+qWo1
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namedQuery){ |3SM
return getHibernateTemplate "+{>"_KV
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().findByNamedQuery(namedQuery); # ^q87y
} ,g~Iup
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publicList findByNamedQuery(finalString query, m~;}8ObQE
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finalObject parameter){ "WfVZBWG$
return getHibernateTemplate 5%#V>|@e#
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().findByNamedQuery(query, parameter); f[s|<U^
} 50='>|b
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publicList findByNamedQuery(finalString query, ZdsYIRU#
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finalObject[] parameters){ ~^ <1k-
return getHibernateTemplate YA:!ULzR*
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().findByNamedQuery(query, parameters); "+sl(A3`U
} ,CED%
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publicList find(finalString query){ l RM7s(^l
return getHibernateTemplate().find Iss)7I
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(query); 0vjlSHS;`.
} .kf FaK
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publicList find(finalString query, finalObject S"Z.M _
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parameter){ E},^,65
return getHibernateTemplate().find h( V:-D
];
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(query, parameter); <oKoz0!
} 8ZN"-]*
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public PaginationSupport findPageByCriteria >X58 zlxk
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(final DetachedCriteria detachedCriteria){ 9h/JW_
return findPageByCriteria 30fqD1_{
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); LLD#)Jl{?
} R|g50Q
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public PaginationSupport findPageByCriteria 3bBCA9^se
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(final DetachedCriteria detachedCriteria, finalint &peUC n
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startIndex){ A8T75?lL(
return findPageByCriteria kW4B
@Zh
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(detachedCriteria, PaginationSupport.PAGESIZE, duq(K9S
|)[I$]L
startIndex); S(ky:
} kb~;s-$O`s
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public PaginationSupport findPageByCriteria x"83[0ib
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(final DetachedCriteria detachedCriteria, finalint =pnMV"'9
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pageSize, Y2d(HD@
finalint startIndex){ H[ o > "@4
return(PaginationSupport) ~Iz{@Ep*
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getHibernateTemplate().execute(new HibernateCallback(){ u.rFZu?E\
publicObject doInHibernate 0U&@;/?
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(Session session)throws HibernateException { X4dxH_@
Criteria criteria = ^hRx{A
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detachedCriteria.getExecutableCriteria(session); K'f`}y9
int totalCount = G<W;HM j2
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((Integer) criteria.setProjection(Projections.rowCount T8W;Lb9hQ
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()).uniqueResult()).intValue(); pZ)N,O3
criteria.setProjection FByA4VxB
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(null); iPCDxDLN3V
List items = K:L_y1!T
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criteria.setFirstResult(startIndex).setMaxResults c1sVdM}|
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(pageSize).list(); Msst:}QY
PaginationSupport ps = 'B9q&k%<
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new PaginationSupport(items, totalCount, pageSize, wB+X@AA
;2}wrX
startIndex); ;)23@6{R%
return ps; L]Dq1q8`
} A/TCJ#>l
}, true); SQ
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} XP^[,)E
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public List findAllByCriteria(final :y1,OR/k
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DetachedCriteria detachedCriteria){ 1"S~#
return(List) getHibernateTemplate P^^WViVX
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().execute(new HibernateCallback(){ ' '<3;
publicObject doInHibernate |crm{]7X
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(Session session)throws HibernateException { !6FO[^h||H
Criteria criteria = {NUI8AL46A
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detachedCriteria.getExecutableCriteria(session); U28frRa
return criteria.list(); o0 |T<_
} U(:Di]>{
}, true);
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} trz&]v=:
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public int getCountByCriteria(final $&X-ay o
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DetachedCriteria detachedCriteria){ S+bpWA
Integer count = (Integer) c&'5r OY~
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getHibernateTemplate().execute(new HibernateCallback(){ |ngv{g
publicObject doInHibernate fL~@v-l#~
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(Session session)throws HibernateException { 0b}.!k9
Criteria criteria = V*gh"gZ<
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detachedCriteria.getExecutableCriteria(session); ~cul;bb#
return 4SJb\R)XK
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criteria.setProjection(Projections.rowCount
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9@>Q7AUCQ
()).uniqueResult(); nLY(%):(P
} & ^;3S*p
}, true); 3QDz9KwCAw
return count.intValue(); ?$.JgG%Z+g
} w >w zV=R
} ?izl#?
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用户在web层构造查询条件detachedCriteria,和可选的 a5?Yh<cJ
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 \Vx_$E
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PaginationSupport的实例ps。 g\1|<jb3
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ps.getItems()得到已分页好的结果集 AP+%T
ps.getIndexes()得到分页索引的数组 /vs79^&
ps.getTotalCount()得到总结果数 Gq-~zmg
ps.getStartIndex()当前分页索引 (,D:6(R7t
ps.getNextIndex()下一页索引 Xi0fX$-,
ps.getPreviousIndex()上一页索引 HcM/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]GBlads
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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 ` <u2 N
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一下代码重构了。 +
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我把原本我的做法也提供出来供大家讨论吧: $f=6>Kn|^]
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首先,为了实现分页查询,我封装了一个Page类: !8&EkXTw,
java代码: >qZl
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/*Created on 2005-4-14*/ Aw&0R" {
package org.flyware.util.page; LfN,aW
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/** mrBK{@n
* @author Joa )Em`kle
* u.Tknw-X
*/ s8dP=_ `
publicclass Page { Z1_F)5pn
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/** imply if the page has previous page */ beB3*o
privateboolean hasPrePage; [\rzXE
]3~u @6
/** imply if the page has next page */ Y
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privateboolean hasNextPage; J-qUJX~4c
tIS.,CEQF
/** the number of every page */ [I}z\3Z
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privateint everyPage; ueEf>0
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/** the total page number */ "^)GnK +-
privateint totalPage; ^!z(IE'
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/** the number of current page */ -Jt36|O
privateint currentPage; Z!3R
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/** the begin index of the records by the current q:=jv6T#
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query */ 0rvBjlFT
privateint beginIndex; b,X+*hRt
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/** The default constructor */ )Y6\"-M[
public Page(){ {yDQncq'^
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} lOM8%{.'_x
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/** construct the page by everyPage .osG"cS
* @param everyPage qWf[X'
* */ USaa#s4'
public Page(int everyPage){ tu(^D23
this.everyPage = everyPage; \01 kK)
} ?Qx4Z3n
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/** The whole constructor */ P-<1vfThH
public Page(boolean hasPrePage, boolean hasNextPage,
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int everyPage, int totalPage, 5A<}*T
int currentPage, int beginIndex){ ydA@@C\&
this.hasPrePage = hasPrePage; p{:y?0pGN
this.hasNextPage = hasNextPage; CM%;/[WBxy
this.everyPage = everyPage; ?J-\}X
this.totalPage = totalPage; yL),G*[p\}
this.currentPage = currentPage; I9m9`4BK
this.beginIndex = beginIndex; }9glr]=
} jGT|Xo>t
hA;Ai:8
/** c,O;B_}M]
* @return +TX4,"
* Returns the beginIndex. pjl>ZoOM
*/ #c":y5:
publicint getBeginIndex(){ v+}${h9
return beginIndex; __zHe-.m
} 9C=*>I27?
IZ\fvYp
/** /DP0K
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* @param beginIndex 8_o~0lb
* The beginIndex to set. |5ge4,}0
*/ 3rd8mh&l
publicvoid setBeginIndex(int beginIndex){ EJRkFn8XG'
this.beginIndex = beginIndex; Ke=+D'=
} 6kMkFZ}+
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/** W\j)Vg__e
* @return k"C'8<T)'
* Returns the currentPage. l}r 9kS
*/ hg#O_4D
publicint getCurrentPage(){ ?#fm-5WIi
return currentPage; !|j|rYi-
} E m^Dg9
\ q3ui}-9
/** *A4eYHn@
* @param currentPage y. 1F@w|
* The currentPage to set. M<*WC{
*/ cD=IFOB*GD
publicvoid setCurrentPage(int currentPage){ NUJ $)qNA
this.currentPage = currentPage; z@w}+fYO
} JZ~wacDd
%n GjP^
/** :Ocw+X3
* @return [~X&J#
* Returns the everyPage. Z[ &d2'
*/ 0w0{@\9
publicint getEveryPage(){ g<,0kl2'S
return everyPage; M] +.xo+A
} bM5o-U#^ C
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/** U]w"T{;@.)
* @param everyPage KV$4}{
* The everyPage to set. FvG?%IFM
*/ c8Ud<M .
publicvoid setEveryPage(int everyPage){ Zd%wX<hU"
this.everyPage = everyPage; XogCq?_m
} v;U5[
rGXUV`5Na
/** RjTGm=1w
* @return X,#~[%h$-=
* Returns the hasNextPage. (vX<Bh
*/ vC`SD]
publicboolean getHasNextPage(){ LkP
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return hasNextPage; Xx%<rsA>F
} )J0h\ky
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/** [p~,;%
* @param hasNextPage c#"t.j<E}
* The hasNextPage to set. -u4")V>
*/ B /w&Lo
publicvoid setHasNextPage(boolean hasNextPage){ F?05+
this.hasNextPage = hasNextPage; bk;uKV+<
} RPte[tq
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/** y1T(R#
* @return 5ya^k{`+ZO
* Returns the hasPrePage. tl\<:8pI"
*/ {V[}#Mf
publicboolean getHasPrePage(){ ^G(Ee+PN@
return hasPrePage; OXbShA&1
} V>,=%r4f
'P" i9j
/** )7.DF|A
* @param hasPrePage &e;Qabwxva
* The hasPrePage to set. vJ=Q{_D=\
*/ CswKT9
publicvoid setHasPrePage(boolean hasPrePage){ \q4r/SbgW
this.hasPrePage = hasPrePage; '
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} 7gZ}Qy
Mqvo
j7
/** dFDf/tH
* @return Returns the totalPage. i}P{{kMJ
* rQ_@q_B.
*/ 8.8t$
publicint getTotalPage(){ # Q,EL73;
return totalPage; X<Z(,B
} 3X1 1Gl
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/** zBTW&
* @param totalPage :?BK A0E
* The totalPage to set. S\<i`q
*/ ^.\O)K {h
publicvoid setTotalPage(int totalPage){ M}# DX=NZc
this.totalPage = totalPage; uf9&o#
} QDV+(
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} 9A} *
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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 4C%pKV
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个PageUtil,负责对Page对象进行构造: Es)|#0m\x@
java代码: Y$\|rD^f
matna
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/*Created on 2005-4-14*/ M3O !jN~
package org.flyware.util.page; 2M'dTXz
RK &>!^
import org.apache.commons.logging.Log; *wj5( B<y
import org.apache.commons.logging.LogFactory; 16~E
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/** rf:H$\yw
* @author Joa HOFxOBV
* kDWEgnXK,v
*/ 7#%Pry
publicclass PageUtil { LlO8]b!P-^
@x+2b0 b
privatestaticfinal Log logger = LogFactory.getLog 4}v|^_x-i
;-kDJi
(PageUtil.class); BR@m*JGajz
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/** B6k<#-HAT
* Use the origin page to create a new page 6X%g-aTs
* @param page )3:0TFS}}k
* @param totalRecords >>$`]]7
* @return &k%>u[Bo
*/ /G'3!S
publicstatic Page createPage(Page page, int A8*zB=C
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totalRecords){ ">z3i`#C'
return createPage(page.getEveryPage(), tMX$8W0
c
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page.getCurrentPage(), totalRecords); %J^x `P
} ^zQI_ydG
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/** 2*V[kmD/3
* the basic page utils not including exception #xw*;hW<
!h7.xl OpN
handler 5HV+7zU5
* @param everyPage ,_RNZ
sa;&
* @param currentPage %csrNf
* @param totalRecords -"dt3$ju
* @return page e@ZM&iR
*/ m\0_1 #(
publicstatic Page createPage(int everyPage, int /~ {`!30
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currentPage, int totalRecords){ 0zB[seyE
everyPage = getEveryPage(everyPage); ]>VG}e~b
currentPage = getCurrentPage(currentPage); >- \bLr
int beginIndex = getBeginIndex(everyPage, ")STB8kQ
nwUz}em?O
currentPage); q_h (D/g
int totalPage = getTotalPage(everyPage, Bso#+v5
A,c XN1V
totalRecords); qGV_oa74
boolean hasNextPage = hasNextPage(currentPage, V>`ANZ4
Fds
11
/c7
totalPage); =oq8SL?bJ*
boolean hasPrePage = hasPrePage(currentPage); KZw~Ch}b9
ggx_h
returnnew Page(hasPrePage, hasNextPage, +wmG5!%$|
everyPage, totalPage, P8,Ps+
currentPage, 4>>=TJ!M
2.Qz"YDh
=
beginIndex); ?zf3Fn2y
} zR^Gy"
i9DD)Y<
privatestaticint getEveryPage(int everyPage){ M>]A!W=
return everyPage == 0 ? 10 : everyPage; \MOwp@|y
} j,+]tHC-
]$[sfPKA
privatestaticint getCurrentPage(int currentPage){ *kl :/#
return currentPage == 0 ? 1 : currentPage; $}gMJG
} k_=yb^6[U
jfY7ich
privatestaticint getBeginIndex(int everyPage, int Ey|_e3Lf[
Qw}1q!89
currentPage){ !ka* rd
return(currentPage - 1) * everyPage; !B}9gT
} 7t:RQ`$:
yQD>7%x
privatestaticint getTotalPage(int everyPage, int SXm%X(JU
Mz(Vf1pi%
totalRecords){ ?1SsF>|
int totalPage = 0; rm,`M
W8^m-B&
if(totalRecords % everyPage == 0) zl|z4j'Irc
totalPage = totalRecords / everyPage; YOD.y!.zq7
else TQF+aP8[L
totalPage = totalRecords / everyPage + 1 ; GBbnR:hM
#4msBax4
return totalPage; x?+w8jSR
} :x*)o+
T`ibulp
privatestaticboolean hasPrePage(int currentPage){ "0P`=n
return currentPage == 1 ? false : true; 20|`jxp
} \xkKgI/
&Vz$0{d5
privatestaticboolean hasNextPage(int currentPage, 3S:Lce'f
:hX[8u
int totalPage){ qq| 5[I.?
return currentPage == totalPage || totalPage == ukW&\
"tzu.V-
0 ? false : true; 9Rnypzds
} }aVZ\PDg
6QX m]<
`OBzOM
} kt/,& oKI
s{Z)<n03
MY^{[#Q
:CyHo6o9
J,2V&WuV0r
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 D0r viO
147QB+cE
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 CI'RuR3y]Z
iAwEnQ3h
做法如下: ^a4z*#IOr
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 x;n3 Zr;(
D(AH3`*|#
的信息,和一个结果集List: 6}"c4^k6
java代码: dI{DiPho
~|V^IJZ22
faDSyBLo
/*Created on 2005-6-13*/ `t~jHe4!Y
package com.adt.bo; 2s\ClT
f2i:I1 p("
import java.util.List; 08`|C)Z!
#Vq9 =Q2
import org.flyware.util.page.Page; :aesG7=O
0ns\:2)cEB
/** }Y~Dk]*
* @author Joa Lnr9*dm6q
*/ Iux3f+H
publicclass Result { @Jzk2,rI
.A2$C|a*
private Page page; i}) s4%a
5?kfE
private List content; ?h= n5}Y
v`HER6
/** nI\6aG?`
* The default constructor Y}:~6`-jj
*/ uzy5rA==
public Result(){ 9P?0D
super(); pM?;QG;jA
} JE?rp1.
3e_tT8
/** q<JCgO-F<
* The constructor using fields ;w7 mr1
* i+Z)`
* @param page O$,Fga
* @param content )U@9dV7u
*/ utlr|m Xc
public Result(Page page, List content){ u\]EG{w(
this.page = page; !_S#8"
this.content = content; ~||0lj.D
} 6hxZ5&;(*
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/** QNj]wm=mp
* @return Returns the content. Re$h6sh
*/ G;Li!H
publicList getContent(){ Nd~B$venh
return content; s2;~FK#/
} uoS:-v}/Y~
G{U#9
/** IiU> VLa
* @return Returns the page. XB)D".\
*/ U\KMeaF5e-
public Page getPage(){ M.W
X&;>
return page; T
ozx0??)
} (bsx|8[
|&; ^?M
/** QL?_FwZL
* @param content z
6:Wh
* The content to set. f9.?+.^_
*/ hyI7X7Hy
public void setContent(List content){ (8duV
this.content = content; 9LDv?kYr
} k9Pvh,_wp
17LhgZs&
/** 5 ~Wg=u<6
* @param page Z>hTL_|]a{
* The page to set. ;*A'2ymXUT
*/ #-/W?kD
publicvoid setPage(Page page){ wZqYtJ
this.page = page; 4Uy% wB
} =)a24PDG
} cS ~OxAS
3:)z+#Uk6
uO%0rKW
2|nm> 4
@N=vmtLP
2. 编写业务逻辑接口,并实现它(UserManager, Vao:9~
"-~7lY%
UserManagerImpl) |5&+VI
java代码: GEc6;uz<
F B]Y~;(
Y|>dS8f;4
/*Created on 2005-7-15*/ VoU8I ~
package com.adt.service; {)[o*+9
YvR bM
import net.sf.hibernate.HibernateException; r/Y J, 2!
ij"~]I
import org.flyware.util.page.Page; acd[rjeT
GEBSUvM 7
import com.adt.bo.Result; >B BV/C'9
kK6OZhLH
/** g`XngRb|j
* @author Joa W }NUU
*/ oaIk1U;g
publicinterface UserManager { ~k"+5bHa*
'6so(>|
public Result listUser(Page page)throws t R^f]+Up
>!963>D R
HibernateException; n;g'?z=hy
5ZCu6A
} CIudtY(:
Fr9/TI
w,UE0i9I
JJ: ku&Mb
h4Crq Yxa_
java代码: ?uWUs )9
Obs#2>h
wlS/(:02
/*Created on 2005-7-15*/ k<gH*=uXY'
package com.adt.service.impl; J'44j;5&
J9^NHU
import java.util.List; #Hw|P
?CpVA
import net.sf.hibernate.HibernateException; E C#0-,z
;%e&6
import org.flyware.util.page.Page; T{{:p\<]_
import org.flyware.util.page.PageUtil; 6= iHw24
BWt`l,nF
import com.adt.bo.Result; f ,F X# _4
import com.adt.dao.UserDAO; mZ)>^.N6
import com.adt.exception.ObjectNotFoundException; }EK{UM9y
import com.adt.service.UserManager; <,i4Ua
5'2kP{;
/** RSX27fb4
* @author Joa 9YzV48su#
*/ #;[G>-tC
publicclass UserManagerImpl implements UserManager { [vg&E
)V
oC0ndp~+&
private UserDAO userDAO; 56V|=MzX]
;mQj2Bwr
/** #]` uH{
* @param userDAO The userDAO to set. fBS a8D3}`
*/ a"Qf
publicvoid setUserDAO(UserDAO userDAO){ 4~fYG| a
this.userDAO = userDAO; NL21se
} %M6OLq!K
K;F1'5+=D
/* (non-Javadoc) 01cBAu
* @see com.adt.service.UserManager#listUser Q\Ek U.[I
/%@;t@BK4
(org.flyware.util.page.Page) fG0 ?"x@>
*/ gZ @+62
public Result listUser(Page page)throws RGW@@
'I[?R&j$G
HibernateException, ObjectNotFoundException { fdl.3~.C
int totalRecords = userDAO.getUserCount(); c(Q@5@1y:
if(totalRecords == 0) dC C*|b8h
throw new ObjectNotFoundException &
3#7>oQ
v$ ti=uk$
("userNotExist"); m2]N%Y
page = PageUtil.createPage(page, totalRecords); o[Iu9.zJpy
List users = userDAO.getUserByPage(page); f{BF%;
returnnew Result(page, users); n0(Q/
} f%G\'q]#F
u`MMK4 %
} hD6BP
pH'_k k
^<I(
>pq~ &)^u
@16GF!.
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 p9v:T1?
7=-Yxt
询,接下来编写UserDAO的代码: QiK>]xJ'
3. UserDAO 和 UserDAOImpl: qTsy'y;Z
java代码: zdN[Uc+1Bd
b:==:d:0s
z.Cj%N
/*Created on 2005-7-15*/ o'2eSm0H
package com.adt.dao; YT(N][V
kx,.)qKk
import java.util.List; =p5DT
Ho &Q}<(
import org.flyware.util.page.Page; F#Lo^ 8
;1k&}v&
import net.sf.hibernate.HibernateException; E&U_1D9=L<
]!/
/** J0xHpe
* @author Joa qb>ULP0
*/ r:*G{m-
publicinterface UserDAO extends BaseDAO { ON2o^-%=
j=r1JV
@
publicList getUserByName(String name)throws IeYYG^V<A
_ *f>UW*,
HibernateException; omE- c
KC;cu%H
publicint getUserCount()throws HibernateException; I&-r^6Yx
+_GS@)L`%
publicList getUserByPage(Page page)throws 3^8Cc(bk
*.W3V;K
HibernateException; -.Wcz|
gAAC>{Wh
} -S$F\%
4H{t6t@-:
7^dr[.Q[*
"*d6E}wG
\^)i!@v
java代码: a?[[F{X9^
Iz0$T.T
Q'OtXs 80
/*Created on 2005-7-15*/ /U;j-m&
package com.adt.dao.impl; ;Y7'U rn
#Y7jNrxE
import java.util.List; '1mk;%
O= S[n
import org.flyware.util.page.Page; VLXA6+
ddQ+EY@!
import net.sf.hibernate.HibernateException; wJC[[_"3 I
import net.sf.hibernate.Query; D$l!lRu8+L
wf8{v
import com.adt.dao.UserDAO; :>FN|fz
J(]|)?x2
/** (*S<2HN5
* @author Joa Am,{Fj
*/ +?J N_aR
public class UserDAOImpl extends BaseDAOHibernateImpl )Zq'r L<
ciS +.%7
implements UserDAO { $nt&'Xnv
{irc0gI
/* (non-Javadoc) 0'o[2,
* @see com.adt.dao.UserDAO#getUserByName <h -)zI
Tg{5%~L]
(java.lang.String) Q yqOtRk
*/ Kd:l8%+
publicList getUserByName(String name)throws En\@d@j<u
r=Xo; d*TE
HibernateException { ;,77|]<XE
String querySentence = "FROM user in class Oiib2Ov
Fm`*j/rq
com.adt.po.User WHERE user.name=:name"; N@d~gE&^
Query query = getSession().createQuery =u2 z3$
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(querySentence); 24J c`%7,=
query.setParameter("name", name); p%DU1+SA
return query.list(); sxT&T=7
} o`YBz~2
cL9gaD$;)
/* (non-Javadoc) u}du@Aq
* @see com.adt.dao.UserDAO#getUserCount() 5*44QV
*/ |[`YGA4
publicint getUserCount()throws HibernateException { 9]eG|LFD
int count = 0; 7O55mc>cF
String querySentence = "SELECT count(*) FROM 9&sb,^4
0YiTv;mq;
user in class com.adt.po.User"; 5]&sXs
Query query = getSession().createQuery Lm[,^k
M-@RgWvF
(querySentence); 2Q e&FeT
count = ((Integer)query.iterate().next A4zI1QF
pX&bX_F{
()).intValue(); /@\`Ibe
return count; T=PqA)Ym
} "z9C@T
2;gvo*k
/* (non-Javadoc) 'KH+e#?Ar
* @see com.adt.dao.UserDAO#getUserByPage 4X^$"lM
C3'xU` =7
(org.flyware.util.page.Page) 9~hW8{#
*/ p{,#H/+J
publicList getUserByPage(Page page)throws ny
KfM5s_
Z@s[8wrmPl
HibernateException { LK} g<!o(
String querySentence = "FROM user in class %`i*SF(gV
8\s#law
com.adt.po.User"; p7QZn.,=u
Query query = getSession().createQuery P!79{ 8
(_ G>dP_
(querySentence);
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query.setFirstResult(page.getBeginIndex()) |y^=(|eM
.setMaxResults(page.getEveryPage()); -))S
return query.list(); b-ss^UL
} ==Egy:<:Q
'&cH,yc;b
} lp(2"$nQ
'~Y@HRVL@|
_:[@zxT<x
xt|^~~ /
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}Ba02F
至此,一个完整的分页程序完成。前台的只需要调用 wN.S]
~u&gU1}
userManager.listUser(page)即可得到一个Page对象和结果集对象 dFBFXy
sFM$O232
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)M#9oAM
'I>USl3 hI
webwork,甚至可以直接在配置文件中指定。 PA'&]piPl:
|$\K/]q-
下面给出一个webwork调用示例: Mp/l*"(
java代码: 5n?P}kca)
$
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*Z#OfB4}
/*Created on 2005-6-17*/ m ""+$
package com.adt.action.user; 6 J>A U
4'z)J1M
import java.util.List; V8/4:Va7s
SMrfEmdH+
import org.apache.commons.logging.Log; <&m50pq
import org.apache.commons.logging.LogFactory; Z3&}C h
import org.flyware.util.page.Page; m[eqTh4*
-6+7&.A+
import com.adt.bo.Result; P4@`C{F5m
import com.adt.service.UserService;
OMK,L:poC
import com.opensymphony.xwork.Action; JlYZ\
@<P2di
/** n~UI47
* @author Joa wH?)ZL
*/ yx Om=V
publicclass ListUser implementsAction{ 8xENzTR
^2-
<XD)
privatestaticfinal Log logger = LogFactory.getLog WO.u{vW]'
m%6VwV7U
(ListUser.class); =p_*lC%N
TVcA%]y{;
private UserService userService; E!ndXz 59
0Fb];:a
private Page page; 9)7$U QY
Go{,<
gm
privateList users; `h@fW- r
\96\!7$@O
/* QdgJNT<=H,
* (non-Javadoc) ;mEn@@{
* O q$_ q
* @see com.opensymphony.xwork.Action#execute() jRjeL'"G
*/ 1dLc/,|
publicString execute()throwsException{ (T*$4KGV
Result result = userService.listUser(page); OK]Q Db
page = result.getPage(); ,gw9R9 x_
users = result.getContent(); <7]HM5h
return SUCCESS; KAnV%j
} jh/,G5RM9
BP9#}{kE
/** %rb$tKk
* @return Returns the page. 9nN1f@Y
*/ 36{GZDGQ
public Page getPage(){ >[Vc$[62
return page; =sk[I0W
} ~1+6gG
+4-T_m/W/
/** 8GP17j
* @return Returns the users. $~1vXe
*/ ketp9}u
publicList getUsers(){ bVzi^R"
return users; }O*`I(
} Y5tyFi#w[
ai-s9r'MI?
/** 7}VqXUwabx
* @param page :m<&Ff}
* The page to set. rhc+tR
*/ |BFzTz,o
publicvoid setPage(Page page){ T^7Cv{[
this.page = page; s21}
a,eB
} 67iI wY*8'
!Q[v"6?
/** y2I7Zd .
* @param users rD=D.1_
* The users to set. -g~+9/;n
*/ .f_
A%
publicvoid setUsers(List users){ \<pr28
this.users = users; v\,N"X(,
} E<\$3G-do
bqED5;d'#
/** nx'c=gp
* @param userService O=3/qs6m
* The userService to set. tQ{/9bN?P
*/ bvtpqI QZ
publicvoid setUserService(UserService userService){ _H]^7`;
this.userService = userService; ]"_c-=
} }AS/^E
} 5z_d$.CIc
5VV}w R
0<%$lr
MOD&3>NI
Zkd{EMW
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, \o!3TK"N
#`u}#(
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 nW)+-Wxq
p{L;)WTI
么只需要: 1*8;)#%&
java代码: cp@Fj"
2Xl+}M.:Y
<}J!_$A
<?xml version="1.0"?> `xzKRId0
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 5e+j51
!ekByD
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 6axxyh%
\!\:p/f
1.0.dtd"> Bg]VaTm[=
J|BElBY
<xwork> ^^V3nT2rR3
Y2DL%'K^
<package name="user" extends="webwork- tA#$q;S
x/O;8^b
interceptors"> SxYz)aF~
i]c{(gd`
<!-- The default interceptor stack name W p)!G
jg?UwR&
--> 4"2%mx:
<default-interceptor-ref bX$z)]KKu
WRD
z*Zf
name="myDefaultWebStack"/> {c*$i^T
@l CG)Ix<
<action name="listUser" v8-My1toV
Lw\u{E@
class="com.adt.action.user.ListUser"> .h W>#
<param XN<!.RCw
Z^V;B _
name="page.everyPage">10</param> h*VDd3[#
<result j~N*T XkC
H=BI%Z
name="success">/user/user_list.jsp</result> 9:{<