Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n.H`1@
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 r<f-v_bxF
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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 i7w}`vs
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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 ~BYEeUo;%v
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分页支持类: 0 *Yivx6
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java代码: Nm:|C 3_I
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package com.javaeye.common.util; s)&R W#:X
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import java.util.List; xzf)_ <
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publicclass PaginationSupport { >8mW-p
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publicfinalstaticint PAGESIZE = 30; 5bqYi
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privateint pageSize = PAGESIZE; {Z~VO
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privateList items; V{aIhH>P
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privateint totalCount; P@T $6%~
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privateint[] indexes = newint[0]; Y<$"]@w
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privateint startIndex = 0; zm^p7&ak$
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public PaginationSupport(List items, int v_F?x!
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totalCount){ x?k |i}Q
setPageSize(PAGESIZE); w7ABnX
setTotalCount(totalCount); "@'9+$i6
setItems(items); ; >hPHx
setStartIndex(0); h^,YYoA$
} d5W[A#}
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public PaginationSupport(List items, int vH\nL>r
O7_NXfh|
totalCount, int startIndex){ %RF
setPageSize(PAGESIZE); "lj:bxM2C
setTotalCount(totalCount); &(U=O?r7
setItems(items); I3=Sc^zz&V
setStartIndex(startIndex); ha'm`LiX
} #S74C*'8
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public PaginationSupport(List items, int mp$II?hZ*
\Hx#p`B%
totalCount, int pageSize, int startIndex){ ,T>2zSk
setPageSize(pageSize); +( 7vmC.
setTotalCount(totalCount); w9?wy#YI
setItems(items); *xN jhR]7v
setStartIndex(startIndex); K?<Odw'k
} j{+I~|ZB,
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publicList getItems(){ W$ {sD|d-
return items; 4>eg@s N
} JZ0+VB-3U
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publicvoid setItems(List items){ |&*rSp2iH
this.items = items; IZ ha* 7
} T{2//$T?
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publicint getPageSize(){ VFp)`+8
return pageSize; RR {9
} [9Hm][|Ph
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publicvoid setPageSize(int pageSize){ xo3)dsX
this.pageSize = pageSize; X7!A(q+h
} *VAi!3Rx;
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publicint getTotalCount(){ ;Awzm )Q
return totalCount; zT 40,rk
} \}(-9dr
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publicvoid setTotalCount(int totalCount){ F#9KMu<<cI
if(totalCount > 0){ l@9:VhU(
this.totalCount = totalCount; _E-GHj>k
z
int count = totalCount / wY)GX
nr6[rq
pageSize; -2XIF}.Hu
if(totalCount % pageSize > 0) +n]Knfi
count++; Cf 8-%
indexes = newint[count]; 6/C
for(int i = 0; i < count; i++){ J)~=b_'<
indexes = pageSize * g4932_tC
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i; JIkmtZv
} :zZM&r>
}else{ wn.0U
this.totalCount = 0; F=lj$?4{
} "A$Y)j<#G
} ^E8Hv
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publicint[] getIndexes(){ LD"}$vfs
return indexes; g[Y$SgJ
} dv>zK#!
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publicvoid setIndexes(int[] indexes){ 1&WFs6
this.indexes = indexes; A~t7I{`
} *gKr1}M
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publicint getStartIndex(){ }jXUd=.Nu
return startIndex; Kqjeqr@)
} b?^<';,5
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publicvoid setStartIndex(int startIndex){ (6aZQ`H
if(totalCount <= 0) uSbg*OA
this.startIndex = 0; }gt~{9?c
elseif(startIndex >= totalCount) |1x,_uyQ%
this.startIndex = indexes @T T[H*,
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[indexes.length - 1]; 11'Tt!
elseif(startIndex < 0) 6<GWDO
this.startIndex = 0; a_x6 v*
else{ Ku# _
this.startIndex = indexes (\_d'Js(;
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[startIndex / pageSize]; [\p0eUog/
} hWJc
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} N:zSJW`1
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publicint getNextIndex(){
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int nextIndex = getStartIndex() + C<)&qx3
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pageSize; _u!G6
if(nextIndex >= totalCount) R["7%|RV
return getStartIndex(); Fx\Re]~n
else EtG)2)
return nextIndex; 1gr jK.x
} <WmCH+>?r
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publicint getPreviousIndex(){ cke[SUH,
int previousIndex = getStartIndex() - woKdI)f$
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pageSize; C,rZ}-
if(previousIndex < 0) 7]Yd-vA
return0; iE5^Xik,
else R&p5 3n
return previousIndex; XDQ1gg`
} :4TcCWG
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} &3. 8i%
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抽象业务类 jTIn@Q
java代码: H9?~#GPb
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/** l+,rc*-j0
* Created on 2005-7-12 Ab)7hCUW
*/ Z5K,y19/~
package com.javaeye.common.business; P{ o/F
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import java.io.Serializable; a{=~#u8
import java.util.List; 6]*qx5m`<l
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import org.hibernate.Criteria; fQh!1 R
import org.hibernate.HibernateException; ,#{aAx|]
import org.hibernate.Session; D1a4+AyI
import org.hibernate.criterion.DetachedCriteria; vbU{Et\^
import org.hibernate.criterion.Projections; 4a~_hkY]
import +{Ttv7l_2
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org.springframework.orm.hibernate3.HibernateCallback; Qp}<8/BM\
import 'u~use"
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org.springframework.orm.hibernate3.support.HibernateDaoS ;8UHPDnst
jw)t"S/E
upport; Wj0([n
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import com.javaeye.common.util.PaginationSupport; Ym6[~=~EK
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public abstract class AbstractManager extends xe'*%3-v)
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HibernateDaoSupport { [o6d]i!
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privateboolean cacheQueries = false; |{(ynZ]R
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privateString queryCacheRegion; QQJcvaQ
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publicvoid setCacheQueries(boolean L`BLkDm
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cacheQueries){ `B~%TEvMh
this.cacheQueries = cacheQueries; e BPMT
} P=.W.oS
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publicvoid setQueryCacheRegion(String
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}j
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queryCacheRegion){ pmZr<xs
this.queryCacheRegion = xfilxd
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queryCacheRegion; 1x]G/I*
} /}wGmX! -!
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publicvoid save(finalObject entity){ >*&[bW'}?
getHibernateTemplate().save(entity); \W4SZR%u
}
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publicvoid persist(finalObject entity){ ;XjKWM;
getHibernateTemplate().save(entity); G|V ^C_:
} e>/PW&Z8Z
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publicvoid update(finalObject entity){ RAvV[QkT
getHibernateTemplate().update(entity); f-PDgs
} pLRHwL.
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publicvoid delete(finalObject entity){ xZhh%~
getHibernateTemplate().delete(entity); 0z.&
} B; ~T|ex u
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publicObject load(finalClass entity, fE >FT9c
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finalSerializable id){ 7J)-WXk
return getHibernateTemplate().load /}V9*mD2
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(entity, id); ~{J.br`
} ?U&onGy
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publicObject get(finalClass entity, j&F&wRD%r
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finalSerializable id){ l ^{]pD
return getHibernateTemplate().get u
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(entity, id);
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} sf%=q$z
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publicList findAll(finalClass entity){ 'O
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return getHibernateTemplate().find("from U^.$k-|k
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" + entity.getName());
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} >[[< 5$,T
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publicList findByNamedQuery(finalString 27)$;1MT:
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namedQuery){ mIOx)`$
return getHibernateTemplate ~yci2{
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().findByNamedQuery(namedQuery); {aU~[5L3(
} FG?B:Zl%T
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publicList findByNamedQuery(finalString query, -)w/nq
avdi9!J2
finalObject parameter){ @>da%cX
return getHibernateTemplate k(et b#
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().findByNamedQuery(query, parameter); y2)~ljR
} /@q_`tU
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publicList findByNamedQuery(finalString query, B<i1UJ5
${e{#
finalObject[] parameters){ ?;\YiOTda
return getHibernateTemplate <[(xGrEZV
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().findByNamedQuery(query, parameters); W;2y.2*
} Xod#$'M>
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publicList find(finalString query){ 'Kl} y,
return getHibernateTemplate().find 7z`)1^M
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(query); ! @|"84
} S);bcowf_
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publicList find(finalString query, finalObject n{|~x":9V
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parameter){ Yf|+p65g
return getHibernateTemplate().find iX}EJD{f
fy7]I?vm@
(query, parameter); od$Cm5
} Rzw}W7zg[
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public PaginationSupport findPageByCriteria k |M
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(final DetachedCriteria detachedCriteria){ %G>*Pez%
return findPageByCriteria $33wK
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ymx/N+Jl
} ``U>9S"p)
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public PaginationSupport findPageByCriteria ONg_3vD{
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(final DetachedCriteria detachedCriteria, finalint (FP-
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startIndex){ [8![UcMq
return findPageByCriteria 8KN0z<
^C_ ;uz
(detachedCriteria, PaginationSupport.PAGESIZE, V4iN2
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startIndex); bDRl}^aO6
} 4;y*y tY*
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public PaginationSupport findPageByCriteria @} qMI
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(final DetachedCriteria detachedCriteria, finalint y@e/G3
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pageSize, '8PZmS8X9
finalint startIndex){ "cj6i{x,~w
return(PaginationSupport) fn;`V it#
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getHibernateTemplate().execute(new HibernateCallback(){ lh{U@,/
publicObject doInHibernate =[`B -?
s
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(Session session)throws HibernateException { vjmNS=l
Criteria criteria = TZ3"u@ 06
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detachedCriteria.getExecutableCriteria(session); |L,_QXA2
int totalCount = Sjv_% C$
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((Integer) criteria.setProjection(Projections.rowCount tP^2NTs%]
Z0 @P1
()).uniqueResult()).intValue(); /'O?
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criteria.setProjection nF`_3U8e
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(null); '9.L5*wh]
List items = \AQ*T`Dq
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criteria.setFirstResult(startIndex).setMaxResults v4OroG=^
#-W
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(pageSize).list(); i_Ol vuy~
PaginationSupport ps = 9bwG3jn4?
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new PaginationSupport(items, totalCount, pageSize, QbrR=[8b
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startIndex); ,%6!8vX
return ps; {el[W,CT#
} Tmjcc(
}, true); h6`v%7H?
} ]O]6O%.ao
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public List findAllByCriteria(final +6-_9qRq
1 UdET#\
DetachedCriteria detachedCriteria){ #\1)Tu%-
return(List) getHibernateTemplate m#|;?z
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().execute(new HibernateCallback(){ RA^6c![
publicObject doInHibernate rU/8R'S
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(Session session)throws HibernateException { w]1Ltq*g/
Criteria criteria = /#TtAkH
Bre:_>*
detachedCriteria.getExecutableCriteria(session); #:[^T,YD0
return criteria.list(); q|h#J}\
} x`n7D
}, true); +@G#Z3;l!
} (}*1,N!#
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public int getCountByCriteria(final P.#@1_:gC
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DetachedCriteria detachedCriteria){ jEu-CU#:
Integer count = (Integer) Qv1<)&Ft<
pm` f?Py
getHibernateTemplate().execute(new HibernateCallback(){ oDW)2*8yF
publicObject doInHibernate r|av|7R
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(Session session)throws HibernateException { zPm|$d
Criteria criteria = n~_;tO
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detachedCriteria.getExecutableCriteria(session); nOTe 3?i>
return gUGMoXSTI|
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criteria.setProjection(Projections.rowCount o3C GG
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()).uniqueResult();
}o[NB
} "*8>` 6 E
}, true); LiyR,e
return count.intValue(); ?LSwJ
@#
} R/EpfYOX
} 4p<c|(f#
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用户在web层构造查询条件detachedCriteria,和可选的 <P@ "VwUX
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 tZ>'tE
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PaginationSupport的实例ps。 H"NBjVRU%
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ps.getItems()得到已分页好的结果集 M.qE$
ps.getIndexes()得到分页索引的数组 ?+_Y!*J2b
ps.getTotalCount()得到总结果数 SDu%rr7sQ
ps.getStartIndex()当前分页索引 rczwxWK
ps.getNextIndex()下一页索引 !,<rW<&;
ps.getPreviousIndex()上一页索引 f D<0V
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }Jo}K)>!
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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 K?@x'q1
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一下代码重构了。 =xjtPmZ5X
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我把原本我的做法也提供出来供大家讨论吧: _a\$uVZ
tq=7HM
首先,为了实现分页查询,我封装了一个Page类: yk0^m/=C(
java代码: T_ j0*A$
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/*Created on 2005-4-14*/ 0ky3rFSh1
package org.flyware.util.page; }hA)p:
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/** uWLf9D "
* @author Joa Pd+Wb3
* Ow0( q^H<
*/ ^tL]QE?|
publicclass Page { Mj W{JR)I
0`4Fa^o]h
/** imply if the page has previous page */ k r5'E#
privateboolean hasPrePage; Wgm{
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/** imply if the page has next page */ (V>/[Ev
privateboolean hasNextPage; zP>=K
nNhb,J
/** the number of every page */ 1`2lq~=GV
privateint everyPage; a;f A0_
N)EJP~0
/** the total page number */ +{\b&q_
privateint totalPage; 9w<k1j
PNpH)'C|
/** the number of current page */ &UQP9wS4v
privateint currentPage; H<Zs2DP`
N&G;`
/** the begin index of the records by the current 'XI-x[w
#]2,1dJ
query */ RY}:&vWDk
privateint beginIndex; obK6GG?ZE
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/** The default constructor */ [Qn=y/._r
public Page(){ r)gtx!bx
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} 7Ga'FT.F
rsD?
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/** construct the page by everyPage Ubv_a
* @param everyPage Zr|\T7w 3
* */ T^@P.zX
public Page(int everyPage){ 6'|NALW
this.everyPage = everyPage; `L
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} |?LUt@r;
*#Iqz9X.Y3
/** The whole constructor */ ug?#Oa
public Page(boolean hasPrePage, boolean hasNextPage, :?$<:
uDMyO<\
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int everyPage, int totalPage, pAH9
int currentPage, int beginIndex){ @rlL'|&X*
this.hasPrePage = hasPrePage; \GCT3$
this.hasNextPage = hasNextPage; 72sBx3 ;
this.everyPage = everyPage; J%P{/ nR
this.totalPage = totalPage; X?SLYm@v
this.currentPage = currentPage; J5zu}U?
this.beginIndex = beginIndex; "v+%F
} p><DA fB
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/** "uU[I,h
* @return q;<Q-jr&O
* Returns the beginIndex. ~2}^
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*/ (*G'~gSX
publicint getBeginIndex(){
++CL0S$e
return beginIndex; 8]&lUMaqVZ
} S%7%@Qs"%
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/** 70E@h=oQ
* @param beginIndex W C3b_ia
* The beginIndex to set. sx][X itR+
*/ ^" 4u1
publicvoid setBeginIndex(int beginIndex){ HE*P0Yf=
this.beginIndex = beginIndex; x=3+@'
} }J] P`v
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/** p/?TU
* @return 'p4b8:X
* Returns the currentPage. }>m3V2>[
*/ N4wMAT:h
publicint getCurrentPage(){ D}K/5iU]a
return currentPage; Ts3(,Y
} Op
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n4G53+y'
/** 5h>t4 [~
* @param currentPage q^+Z>
* The currentPage to set. #mbl4a
*/ Zq>}SR
publicvoid setCurrentPage(int currentPage){ $:<G=
this.currentPage = currentPage; o/p'eY:)
} W'<cAg?
P8;f^3V(+/
/** W'M\DKJ?
* @return <>K@#|%Y&
* Returns the everyPage. Y\ G^W8
*/ 'gv7&$X}4
publicint getEveryPage(){ T(6B,
return everyPage; ,__|SnA.
} -g)*v<Fb5
# fl%~Y
/** Abf=b<bu
* @param everyPage m#(ve1E
* The everyPage to set. {>=#7e-]
*/ ^9I^A!w=
publicvoid setEveryPage(int everyPage){ od~`q4p1(-
this.everyPage = everyPage; .
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} 9C)w'\u9+
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/** i*%2 e)
* @return }V
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* Returns the hasNextPage. \^%5!
*/ Y/w) VV
publicboolean getHasNextPage(){ 4 4kb
return hasNextPage; P1mPC
} _G5MQ%z
yy-\$<j
/** +qEvz<kch
* @param hasNextPage #]5|Qhrr+
* The hasNextPage to set. QZ54Osdl
*/ yi/jZX
publicvoid setHasNextPage(boolean hasNextPage){ yD!V;?EnK
this.hasNextPage = hasNextPage; J#y?^Qm$)<
} ps6c>AN`A&
u3H2\<
/** `?L-{VtM3*
* @return v]HiG_C
* Returns the hasPrePage. U%na^Wu
*/ -/#tQ~{gs
publicboolean getHasPrePage(){ <ArP_!
`3
return hasPrePage; kV Z5>D$
} ywV8s|o
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/** P'6(HT>F?
* @param hasPrePage !S',V&Yb
* The hasPrePage to set. #UH7z 4u
*/ ^ok;<fJ
publicvoid setHasPrePage(boolean hasPrePage){ (N\Zz*PLz
this.hasPrePage = hasPrePage; ;{inhiySN
} <~Tlx:
i>[1^~;
/** jsvD[ \P
* @return Returns the totalPage. VNbq]L(g
* Lay+)S.ta[
*/ Az2$\
publicint getTotalPage(){
<&'r_m
return totalPage; R`:NUGR
} ^50/.Z>
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/** <`q|6XWL
* @param totalPage _k@{>
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* The totalPage to set. Q( KLx )
*/
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publicvoid setTotalPage(int totalPage){ %?EOD=e=
this.totalPage = totalPage; *<! W k\
} =`X@+~%-
#={L!"3?e
} D4r5wc%
ZCMB]bL-e
yX(6C]D
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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 `8TM<az-L
$E4W{ad2jW
个PageUtil,负责对Page对象进行构造: %6"b<
MAO
java代码: 1a90S*M
R6Cm:4m}I
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/*Created on 2005-4-14*/ [,a O*7N
package org.flyware.util.page; wDZFOx0#8
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import org.apache.commons.logging.Log; q$`:/ ehw
import org.apache.commons.logging.LogFactory; LxVd7r VY6
?Y'S
/
/** u
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* @author Joa O`dob&C
* :u{0M&
*/ zux+ooU
publicclass PageUtil { j78xMGKO
GD'C^\EaZ
privatestaticfinal Log logger = LogFactory.getLog .VmI4V?}h
Q[p0bD:
(PageUtil.class); Md
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/** tTyu,%/m
* Use the origin page to create a new page R\:C|/6f
* @param page c)SSi@<
cv
* @param totalRecords :*&wnQMKR
* @return im+2)9f
*/ _'H<zZo
publicstatic Page createPage(Page page, int S53%*7K.
H8K<.RY
totalRecords){ @\!wW-:A
return createPage(page.getEveryPage(), 0 $e;#}
z[v5hhI)4
page.getCurrentPage(), totalRecords); %1VMwqC]E
} ;^DUtr
;
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/** ,mYoxEB kl
* the basic page utils not including exception 45j+n.9=
(4 {49b
handler <\^X,,WtO
* @param everyPage @?Y^=0
* @param currentPage
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* @param totalRecords R/^JyL
* @return page cT0utR&
*/ X_'.@q<!CV
publicstatic Page createPage(int everyPage, int Z{p6Q1u
k #*|-?
currentPage, int totalRecords){ YF>t {|
everyPage = getEveryPage(everyPage); yekIw
currentPage = getCurrentPage(currentPage); &"tce6&
int beginIndex = getBeginIndex(everyPage, \ @N> 38M
P>@`hZ9
o
currentPage); v[a#>!;s
int totalPage = getTotalPage(everyPage, 2J4|7UwJ
;mi0Q.
totalRecords); _;B!6cRLps
boolean hasNextPage = hasNextPage(currentPage, 29sgi"
GPR`=]n& &
totalPage); 3^Yk?kFE
boolean hasPrePage = hasPrePage(currentPage); \;7DS:d@
2hJ{+E.m
returnnew Page(hasPrePage, hasNextPage, M+hc,;6
everyPage, totalPage, jq0tMTb%L
currentPage, 0"2 [I
5h:SH]tn8]
beginIndex); M@'V4oUz
} %&_(IY$d
($S{td;
privatestaticint getEveryPage(int everyPage){ ^Nsl5
return everyPage == 0 ? 10 : everyPage; @5?T]V g
} i9!Urq-
H;sQ]:.*]
privatestaticint getCurrentPage(int currentPage){ R^B2J+O
return currentPage == 0 ? 1 : currentPage; @i{JqHU"
} 3K?0PRg
mzT} C&hfP
privatestaticint getBeginIndex(int everyPage, int )b%c]!
MW`a>'0t?
currentPage){ 7 $9fGo
return(currentPage - 1) * everyPage; "}OFwes
} #>v7"
<
>|Jw,,uf
privatestaticint getTotalPage(int everyPage, int 4|$D.`Wu
xeI ,Kz."
totalRecords){ b(SV_.4,'
int totalPage = 0; #`p>VXBj!
GVl
u4
if(totalRecords % everyPage == 0) @^` <iTK&p
totalPage = totalRecords / everyPage; /M3D[aR<d
else z'qVEHc)
totalPage = totalRecords / everyPage + 1 ; 7%E1F)%
GcU/
return totalPage; i`>X5Da5
} k(
g$_ ]X
<y.D0^68
privatestaticboolean hasPrePage(int currentPage){ "q`%d_
return currentPage == 1 ? false : true; EkL\~^
} nUd\4;J#
*b)b#p
privatestaticboolean hasNextPage(int currentPage, '!.;(Jo
q~^:S~q
int totalPage){ Dz50,*}J
return currentPage == totalPage || totalPage == 13QCM0#
^z^>]Qd
0 ? false : true; +
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} P+b^;+\1s
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^ Wl/
} *.*:(7`
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J7\q#] ?
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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。 5{g9Wh[
JG<3,>@%
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 /J+)P<_ A
@}?D<O8#"#
做法如下: S!q}Pn
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Lq [wabF
%8*d)AB:
的信息,和一个结果集List: 6g"<i}_|
java代码: qE{cCS
$McO'Bye{h
'i(p@m<'
/*Created on 2005-6-13*/ Q'a N|^w"f
package com.adt.bo; 1ZL_;k
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*
import java.util.List; Dgm%Ng
84!4Vz^
import org.flyware.util.page.Page; if}]8
rl^LSz
/** -7O/ed+
* @author Joa ^<VE5OM
*/ JKT+ q*V
publicclass Result { ,j nRt%W
3kQ ^f=Wd
private Page page; >slN:dr0:
(RmED\.]4
private List content; :(b3)K
4:@|q:DR
/** "r
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* The default constructor 0w['jh|,
*/ z=p
public Result(){ 4LjSDgA
super(); oPy zk7{
} C%c `@="b
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/**
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* The constructor using fields | q16%6q
* D&r8V;G[[
* @param page 8-5jr_*
* @param content mG~y8nUtp
*/ SU'1#$69F
public Result(Page page, List content){ m[{&xF|_
this.page = page; DP_Pqn8p&M
this.content = content; iFCH$!
} I|IlFu?O=
6h_ k`z
/** |<|,RI?
* @return Returns the content. V3W85_*
*/ NydW9r:T
publicList getContent(){ \.1b\\
return content; Gr@{p"./z
} N`Xnoehu
)Zf}V0!?+
/** N#)VD\m
* @return Returns the page. G`#gV"PlC
*/ 4_%FSW8-
public Page getPage(){ L[G\+
return page; 5SL>q`t.bd
} pInWKj[y1
ePRM v
/** b2=Q~=Wc
* @param content +Jka :]MW!
* The content to set. px>>]>ZMH
*/ U9o*6`"o
public void setContent(List content){ }PIB b
this.content = content; (I[h.\%
} '(pdk
d+2O^of:T
/** J8v:a`bX&
* @param page h==GdS4
* The page to set. 8}oDRN!J
*/ f5GR#3-h(
publicvoid setPage(Page page){ 9T,QWk
this.page = page; '}`hY1v
} a61eH )a
} {qWG^Db
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quGPk)c
LEngZ~sV/
h!N&gZ[0
2. 编写业务逻辑接口,并实现它(UserManager, X_({};mz
<SM&VOiaOz
UserManagerImpl) Mr NOcx&
java代码: }
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. 02(O
=@KY A(D
/*Created on 2005-7-15*/ ?*R^?[
package com.adt.service; ?3TK7]1V:
(bFWT_CChz
import net.sf.hibernate.HibernateException; KO]?>>5S6
l6B ^sc*@
import org.flyware.util.page.Page; gqdB!l4
=E}%>un
import com.adt.bo.Result; `{|}LFS>
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/** \m~\,em
* @author Joa v6P~XK}G
*/ R`C_CsXir
publicinterface UserManager { W8yfa[z~J
;Q>3N(
public Result listUser(Page page)throws W3V{Xk|
v8vh~^X%P
HibernateException; ({_:^$E\
)Kk(P/s
} x$5nLS2.
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t6%xit+
H=o-ScA
\eMYw7y5M
java代码: 8
1KG1i )
tD~PvUJ
4}8+)Pd
/*Created on 2005-7-15*/ p-yOiG8b}
package com.adt.service.impl; a,57`Ks+n<
>,"D9!
import java.util.List; &Rl3y\
r
[5p7@6:$u
import net.sf.hibernate.HibernateException; KG-k$glD
;vv!qBl|@
import org.flyware.util.page.Page; \,%o>M'
import org.flyware.util.page.PageUtil; QVG0>,+}$
;c
m wh<
import com.adt.bo.Result; @maZlw1q
import com.adt.dao.UserDAO; itC *Z6^
import com.adt.exception.ObjectNotFoundException; %I|+_ z&x
import com.adt.service.UserManager; hKH$AEHEU}
Ss<_K>wk
/** d1uG[
* @author Joa IGK_1@tq
*/ }Uwkef.Q
publicclass UserManagerImpl implements UserManager { 27*(oT
1Oca@E\Z.
private UserDAO userDAO; -0KbdHIKb'
[zh4W*K_cq
/** "\zj][sL
* @param userDAO The userDAO to set. _Xk03\n6
*/ csFJ5
publicvoid setUserDAO(UserDAO userDAO){ 1IF'>*
this.userDAO = userDAO; C DnR
} \o62OfF!
FU(}=5n
/* (non-Javadoc) .,ppGc|*
* @see com.adt.service.UserManager#listUser "doU.U&u
o! 2n}C
(org.flyware.util.page.Page) 3!"b
guE
*/
m[@%{
public Result listUser(Page page)throws +Jo 3rX'`
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HibernateException, ObjectNotFoundException { hP4)8 >
int totalRecords = userDAO.getUserCount(); rAlh&
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if(totalRecords == 0) i!.I;@
throw new ObjectNotFoundException Wlr&g
xZ
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("userNotExist"); %Vw|5yA4
page = PageUtil.createPage(page, totalRecords); BDm88<]
List users = userDAO.getUserByPage(page); [V2omSZo
returnnew Result(page, users); r(,= uLc
} PQU3s$
W?"2;](
} kyRh k\X
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cXOje"5i
-40'[a9E
\tiUEE|k
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 g:uvoMUD
a+YR5*&[OO
询,接下来编写UserDAO的代码: 9zoT6QP4
3. UserDAO 和 UserDAOImpl: -TK|Y"
java代码: {8!ZKlB
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;o-\. =l
/*Created on 2005-7-15*/ TbKP8zw{
package com.adt.dao; )KaLSL>
wVvqw/j*f
import java.util.List; xf V,==uF
k9^+9P^L
import org.flyware.util.page.Page;
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9S:{
import net.sf.hibernate.HibernateException; v+!y;N;Q
fCt^FU
/** /RJ6nmN@}
* @author Joa cX|[WT0[I
*/ .%x"t>]
publicinterface UserDAO extends BaseDAO { ?qd,>
i\kTm?BQZ
publicList getUserByName(String name)throws F,p`-m[q
DEUd[
HibernateException; `G=ztL!gq
H4PbO/{xO
publicint getUserCount()throws HibernateException; toS(UM n
;Pol#0_(
publicList getUserByPage(Page page)throws E3~,+68U
N_u&3CG
HibernateException; Kcscz,
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} <ICZ"F`S
1A7 %0/K-]
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0t#NMW
java代码: d] b~)!VW
I! h(`
'}U_D:o.b
/*Created on 2005-7-15*/ T-L|Q,-{-
package com.adt.dao.impl; xoqiRtlY:
p{iG{
import java.util.List; ioB|*D<U2
q[{:
import org.flyware.util.page.Page; d&}pgb-Md
fH{9]TU_:
import net.sf.hibernate.HibernateException; Zi 2o
import net.sf.hibernate.Query; 1% $d D2
&Q\_;
import com.adt.dao.UserDAO; v-P8WFjca
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/** ]]el|
* @author Joa Uj4Lu
*/ u~$WH, P3
public class UserDAOImpl extends BaseDAOHibernateImpl i0k+l
hnp`s%e,
implements UserDAO { XXa(305
eq^TA1>T
/* (non-Javadoc) vS7/ ~:C
* @see com.adt.dao.UserDAO#getUserByName C>*5=p|T
6-mmi7IfO
(java.lang.String) N=OS\pz
*/ )>(L{y|uYX
publicList getUserByName(String name)throws gKmX^A5<
GE%2/z p
HibernateException { |0tg:\.
String querySentence = "FROM user in class ./5jx2V
:z
B}z^8-
com.adt.po.User WHERE user.name=:name"; Ihdu1]~R{
Query query = getSession().createQuery Gs+\D0o!
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(querySentence); VLf
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query.setParameter("name", name); `@h:_d
return query.list(); m_c O<LB
} U{7 3Xax
X Y~;)<s_
/* (non-Javadoc) .qSBh
hH\
* @see com.adt.dao.UserDAO#getUserCount() "Kyifw?
*/ ?QGmoQ)
publicint getUserCount()throws HibernateException { %0vTA_W
int count = 0; ;(K
String querySentence = "SELECT count(*) FROM ! mm5I#s
NA+&jV
user in class com.adt.po.User"; 92!JKZe
Query query = getSession().createQuery kGpV;F==*
JxjP@nr
(querySentence); vKU`C?,L
count = ((Integer)query.iterate().next
#;d)?
|Dg;(i?
()).intValue(); >[a FOA
return count; $Z/klSEf
} mKV'jm0
L{=l#vu
/* (non-Javadoc) PfyRZ[3)c
* @see com.adt.dao.UserDAO#getUserByPage vK(I3db!
Yj)
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(org.flyware.util.page.Page) 'V&2Xvl%
*/ O:1DOUYXs
publicList getUserByPage(Page page)throws )7W6-.d
qtHfz"p
HibernateException { ?L=A2C\_-
String querySentence = "FROM user in class 9SY(EL
i`+B4I8[
com.adt.po.User"; i|%5
Query query = getSession().createQuery 9UP:J0 `
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(querySentence); &Cq{
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query.setFirstResult(page.getBeginIndex()) .!i0_Rv5x
.setMaxResults(page.getEveryPage()); P<u"97@8a
return query.list(); 6^sHgYR
} e&2wdH&
J/t!-!
} 4b4QbJ$
aM$\#Cx
eaQ90B4
nX._EC
6yI}1g
至此,一个完整的分页程序完成。前台的只需要调用 k,rWa
R uLvG+
userManager.listUser(page)即可得到一个Page对象和结果集对象 }kE87x'
]NtSu%u
的综合体,而传入的参数page对象则可以由前台传入,如果用 ]ZTcOf
kg3ppt
webwork,甚至可以直接在配置文件中指定。 h~w4, T
W
(`c
下面给出一个webwork调用示例: 7UKYmJk.
java代码: *zy'#`>
RlsVC_H\
1kmQX+f
/*Created on 2005-6-17*/ O%-h&C3
package com.adt.action.user; Ziz=]D_
y? "@v.
import java.util.List; '&by3y5w-3
H0a-(
import org.apache.commons.logging.Log; =Y9\DeIZ
import org.apache.commons.logging.LogFactory; pcH<gF(k
import org.flyware.util.page.Page; 0KAj]5nvb
ID4~Gn
import com.adt.bo.Result; ^Dr.DWi{$
import com.adt.service.UserService; 3sFeP&
import com.opensymphony.xwork.Action; 8Mu;U3cIW
U<47WfcW
/** se!mb _!
* @author Joa }>&KUl
*/ )47MFNr~>
publicclass ListUser implementsAction{ ]>Si0%
i[150g?K
privatestaticfinal Log logger = LogFactory.getLog iCTQ]H3
LmQ/#Gx
(ListUser.class); Z)&D`RCf
z/1{OL
private UserService userService; EA|k5W*b
(R'+jWH
private Page page; O"*`'D|hK
ni6r{eSQ
privateList users; 2yKz-"E
$%PVJs
/* &[@\ f^~
* (non-Javadoc) :.iyR
* S &JJIFftO
* @see com.opensymphony.xwork.Action#execute() 5+P@sD
*/ F
Z!J
publicString execute()throwsException{ Y-p<qL|_
Result result = userService.listUser(page); \k@Z7+&7
page = result.getPage(); dB;3.<S=
users = result.getContent(); H9`
f0(H
return SUCCESS; xd8
*<,Wj
} )ofm_R'q*
#tjmWGo,
/** *
OsU Y=;
* @return Returns the page. o>c^aRZ{
*/ #SkX@sl@
public Page getPage(){ TfRGA(+#
return page; ^Y04qeRd
} Ht[{ryTxu
Y
?'tUV
/** &Un6ay
* @return Returns the users. PuXUuJx(
*/ :Q@)*kQH
publicList getUsers(){ /smiopFcq
return users; 5H lWfD
} ksWSMxm
[vTMS2
/** Ct]A%=cZW
* @param page ?a.+j8pbGg
* The page to set. ZA\/{Fw
*/ 7*s8ttX
publicvoid setPage(Page page){ R Fko>d
this.page = page; ~rv})4h
} $/_qE
0a2@b"l
/** .Q>!B?)
* @param users VC-;S7k
* The users to set. (j&A",^^S
*/ Veji^-0E
publicvoid setUsers(List users){ rt4Z;
this.users = users; Zb''mf\
} g4&jo_3:p
$-vo}k%M
/** 'C?NJ~MN
* @param userService Qw)9r{f
* The userService to set. bJ3(ckhq
*/ M>l^%`
publicvoid setUserService(UserService userService){ R,Oe$J<
this.userService = userService; {6
.o=EyM{
} \cuS>G
} x<B'.3y
*'ZN:5%H
x5Zrz<Y$w
hu5!ev2
A^Cj1:,
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, ohQAA h
4TRG.$2[
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 !.Zt[ g}
@CQb[!9C
么只需要: rdJB*Rlkh
java代码: 5bX6#5uP1
ii4B?E
Mkv|TyC
<?xml version="1.0"?> M{N(~ql
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 6Nh0
d^V$Z6*
]
1.0//EN" "http://www.opensymphony.com/xwork/xwork- E9 Y\X
9=+-QdX+0]
1.0.dtd"> WZFH@I28
;-@=
<xwork> }zMf7<C
7#2j>G{?]v
<package name="user" extends="webwork- >nnY:7m
KMjg;!y
interceptors"> RKTb'3H
B0)]s<<
<!-- The default interceptor stack name `M@Ak2gcR+
Y2T$BJJ
--> kA#vByf`v
<default-interceptor-ref 6*XM7'n
svhrf;3:
name="myDefaultWebStack"/> hW2.8f$
&M"ouy Zo9
<action name="listUser" wH6u5*$p
]=&L