Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [>W"R1/
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~Cjz29|gp
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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 [##`Um
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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 YBb)/ZghY
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。 vU=9ydAj?
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分页支持类: a}:A, t<6
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java代码: 2
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package com.javaeye.common.util; 2O
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import java.util.List; '
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publicclass PaginationSupport { rRB~=J"
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publicfinalstaticint PAGESIZE = 30; sX+`wc
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privateint pageSize = PAGESIZE; q@(1Yivk
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privateList items; 7;&(}
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privateint totalCount; *)u?~r(F
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privateint[] indexes = newint[0]; ^:`oP"%-T
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privateint startIndex = 0; cA D[3b[Gk
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public PaginationSupport(List items, int tAF]2VV(e
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totalCount){ i+g~ Uj}h
setPageSize(PAGESIZE); ,V,f2W 4
setTotalCount(totalCount); $@_{p*q
setItems(items); tR kF
setStartIndex(0); R (G2qi
} +a%xyD:.?
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public PaginationSupport(List items, int ZWO)tVw9G
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totalCount, int startIndex){ Q]@c&* _|
setPageSize(PAGESIZE); Fh K&@@_
setTotalCount(totalCount); z
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setItems(items); >OV<_(S4
setStartIndex(startIndex); ~W<CE_/]k
} +b^]Pz5
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public PaginationSupport(List items, int hk%k(^ekU]
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totalCount, int pageSize, int startIndex){ YutQ ]zYA.
setPageSize(pageSize); @5xu>g Kn
setTotalCount(totalCount); l3.
setItems(items); iv*V#J>
setStartIndex(startIndex); .}q]`<]ze
} .u l
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publicList getItems(){ ?~J i-{#X
return items; l<(cd,
} > !L&>OOx
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publicvoid setItems(List items){ H3, ut
this.items = items; 8-m
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} `\bT'~P
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publicint getPageSize(){ W^es;5
return pageSize; C-m*?))go
} `5q
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publicvoid setPageSize(int pageSize){ 5Fmav5
this.pageSize = pageSize; 8TE>IPjm
} v?%LQKO
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publicint getTotalCount(){ rEdY>\'
return totalCount; /.Fj.6U5
} _%~$'Hy
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publicvoid setTotalCount(int totalCount){ S,''>`w
if(totalCount > 0){ $IVwA
this.totalCount = totalCount; %d1draL
int count = totalCount / |t))u`~
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pageSize; |S&5es-yW
if(totalCount % pageSize > 0) K B!5u 9
count++; [ %}u=}@
indexes = newint[count]; :]PM_V|
for(int i = 0; i < count; i++){ Dw_D+7>(v
indexes = pageSize * Iy';x
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} =bLY
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}else{ `S3>3
this.totalCount = 0; N>|XS
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} (u hd "
} <P_ea/5:|
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publicint[] getIndexes(){ ('C7=u&F
return indexes; #]E(N~
} @%hCAm
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publicvoid setIndexes(int[] indexes){ c)}2K0
this.indexes = indexes; #aar9
} AVl~{k|
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publicint getStartIndex(){ x[Im%k
return startIndex; c+kU o$
} ]ikomCg
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publicvoid setStartIndex(int startIndex){ 4-R^/A0
if(totalCount <= 0) N@xg:xr
this.startIndex = 0; -.IEgggf
elseif(startIndex >= totalCount) 6/Fzco#N
this.startIndex = indexes R"AUSO|{
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[indexes.length - 1]; C[uOReo
elseif(startIndex < 0) kW@,$_cK
this.startIndex = 0; w%y\dIeI'
else{ 8X$LC
this.startIndex = indexes k|YWOy@D~
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[startIndex / pageSize]; +Qxu$#
} 71fk.16
} mee$"Y
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publicint getNextIndex(){ -nbMTY}
int nextIndex = getStartIndex() + 5fJ[}~
@U{<a#
pageSize; :hRs`=d"r
if(nextIndex >= totalCount)
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return getStartIndex(); F {+`uG
else r?/A?DMe
return nextIndex; <#M`5X.
} G:W>I=^DaR
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publicint getPreviousIndex(){ N587(wZ
int previousIndex = getStartIndex() - o>Er_r
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pageSize; N K]B?
if(previousIndex < 0) V 9wI\0
return0; N8r*dadDd
else \x{;U#B[3>
return previousIndex; l_rn++
} L!Cz'm"Nl
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} Pmg)v!"
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抽象业务类 OZY, @c
java代码: e({9]
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/** N2'qpxOLI
* Created on 2005-7-12 Z?P~z07
*/ nl aM
package com.javaeye.common.business; j@gMbiu
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import java.io.Serializable; }A=y=+4j
import java.util.List; 4+$b~u
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import org.hibernate.Criteria; xo}b=
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import org.hibernate.HibernateException; 2&PPz}Sw
import org.hibernate.Session; iD38\XNMV
import org.hibernate.criterion.DetachedCriteria; LQ11ba
import org.hibernate.criterion.Projections; J5p"7bc
import 3.d"rl
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org.springframework.orm.hibernate3.HibernateCallback; Uxfl_@lJ
import TL$EV>Nr
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org.springframework.orm.hibernate3.support.HibernateDaoS ._w8J"E5
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upport; J_;N:7'p
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import com.javaeye.common.util.PaginationSupport; /M;#_+VK<
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public abstract class AbstractManager extends u%/fx~t$
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HibernateDaoSupport { i,A#&YDl
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privateboolean cacheQueries = false; 0P^L }VVX
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privateString queryCacheRegion; D\w h;r
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publicvoid setCacheQueries(boolean Ji1Pz)fq
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cacheQueries){ PWRy7d
this.cacheQueries = cacheQueries; GZS1zTwBL
} T{qTj6I
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publicvoid setQueryCacheRegion(String %W,D;?lEo>
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queryCacheRegion){ pLa[}=
this.queryCacheRegion = '{I_\~*
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queryCacheRegion; TD[EQ
} YjF|XPv+ l
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publicvoid save(finalObject entity){ ?Xdak|?i
getHibernateTemplate().save(entity); )VL96 did
} !Fo*e
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publicvoid persist(finalObject entity){ Xs&TJ8a
getHibernateTemplate().save(entity); [,n c
} ~DRmON5 M
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publicvoid update(finalObject entity){ |@ ,|F:h<M
getHibernateTemplate().update(entity); Sxdsv9w
} p4IZ
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publicvoid delete(finalObject entity){ ~\x:<)
getHibernateTemplate().delete(entity); Om{l>24i.\
} PB%-9C0
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publicObject load(finalClass entity, lo%;aK
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finalSerializable id){ ]E =Iu
return getHibernateTemplate().load *Av"JAX
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(entity, id); q-nSLE+_;
} [I4ege>
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publicObject get(finalClass entity, hcVJBK
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finalSerializable id){ y/e2l
return getHibernateTemplate().get dz~co Z9
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(entity, id); bjAnaya
} #r
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publicList findAll(finalClass entity){ ^pM+A6
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return getHibernateTemplate().find("from + <,gB $j
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" + entity.getName()); 7t,t`
} dU\%Cq-G)
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publicList findByNamedQuery(finalString VG/3xR&y
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namedQuery){ .jy]8S8[|%
return getHibernateTemplate yj4+5`|f
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().findByNamedQuery(namedQuery); Ax !+P\\2~
} ==i[w|
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publicList findByNamedQuery(finalString query, Hw#d_P:
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finalObject parameter){ $}")1|U,X
return getHibernateTemplate Ra*e5
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().findByNamedQuery(query, parameter); -
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} GUsl PnG
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publicList findByNamedQuery(finalString query, :4v3\+T
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finalObject[] parameters){ [ sd;`xk
return getHibernateTemplate qj cp65^
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().findByNamedQuery(query, parameters); P{Q=mEQ
} [r/k% <
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publicList find(finalString query){ PRNoqi3sY
return getHibernateTemplate().find Kx_h1{
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(query); wP,JjPUt
} fDx9iHGv
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publicList find(finalString query, finalObject +cU>k}
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parameter){ 8w({\=
return getHibernateTemplate().find ;gC|
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(query, parameter); V.wqZ {G
} 64:fs?H
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public PaginationSupport findPageByCriteria p }[zt#v
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(final DetachedCriteria detachedCriteria){ qY 4#V k
return findPageByCriteria $=?@*p
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); $ cj>2.
} };'\~g,1
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public PaginationSupport findPageByCriteria Zw
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(final DetachedCriteria detachedCriteria, finalint yoAfc
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startIndex){ ePIiF_X
return findPageByCriteria _=|vgc
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(detachedCriteria, PaginationSupport.PAGESIZE, Fd*8N8Pi
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startIndex); TIvRhbu
} 'mV9 {lj7E
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public PaginationSupport findPageByCriteria Z4IgBn(Z_}
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(final DetachedCriteria detachedCriteria, finalint 1
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pageSize, F: mq'<Q
finalint startIndex){ 0Ia($.1mY
return(PaginationSupport) b%cF
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getHibernateTemplate().execute(new HibernateCallback(){ "fq{Y~F%`
publicObject doInHibernate C!7>1I~5
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(Session session)throws HibernateException { ;NlWb =
Criteria criteria = P'Q+GRpSw
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detachedCriteria.getExecutableCriteria(session); s=42uKz
int totalCount = Hty0qr3
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((Integer) criteria.setProjection(Projections.rowCount %\i9p]=
z5TuGYb<
()).uniqueResult()).intValue(); %6_AM
criteria.setProjection qTQBt}
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(null); yv)ux:P&+
List items = sN5B7)Vc
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criteria.setFirstResult(startIndex).setMaxResults *}8t{ F@k
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(pageSize).list(); M`S0u~#tI
PaginationSupport ps = '}Ri`
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new PaginationSupport(items, totalCount, pageSize, n[(Qr9
$v Z$'(
startIndex); } CfqG?)
return ps; IIyI=WlpG
} <I"S#M7-s
}, true); a@R]X5[O
} xZV1k~C
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public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ ;V<fB/S.=+
return(List) getHibernateTemplate @$T 9Ll
*&f$K1p
().execute(new HibernateCallback(){ ;D$)P7k6
publicObject doInHibernate _2N$LLbg
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(Session session)throws HibernateException { g(4xC7xK6
Criteria criteria = 1T[et-
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detachedCriteria.getExecutableCriteria(session); H@l}WihW
return criteria.list(); !fj(tPq
} uIZWO.OdU
}, true); "U7qo}`I
} 5YrBW:_OI
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public int getCountByCriteria(final PiA0]>
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DetachedCriteria detachedCriteria){ 3d|9t9v
Integer count = (Integer) YQY%M>F@d%
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getHibernateTemplate().execute(new HibernateCallback(){ Qf@
publicObject doInHibernate D::rGB?.b
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(Session session)throws HibernateException { yiO.z
Criteria criteria = []D@Q+1
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detachedCriteria.getExecutableCriteria(session); p/h
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return 5L!y-3
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criteria.setProjection(Projections.rowCount 7nuU^wc
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()).uniqueResult(); |6<p(i7
} tPF.r
}, true); ^#sU*trr
return count.intValue(); >vA2A1WhW
} Jkek-m
} pxa(
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用户在web层构造查询条件detachedCriteria,和可选的 Ih"XV
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @mfEKU!
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PaginationSupport的实例ps。 V 0rZz
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ps.getItems()得到已分页好的结果集 ^(FdXGs[
ps.getIndexes()得到分页索引的数组 ' <=+;q
ps.getTotalCount()得到总结果数 ?5{>;#0Z
ps.getStartIndex()当前分页索引 yNbjoFM.i
ps.getNextIndex()下一页索引 pfI"36]F
ps.getPreviousIndex()上一页索引 VzVc37Z>6
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 1{JV}O
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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 j{Q9{}<e
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一下代码重构了。 pS7w' H
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我把原本我的做法也提供出来供大家讨论吧: v%iflCK
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首先,为了实现分页查询,我封装了一个Page类: aSnFKB
java代码: c-0#w=
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/*Created on 2005-4-14*/ BGX.U\uc
package org.flyware.util.page; sdo[D
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/** 3(,?S$>
* @author Joa RtM8yar+sn
* EU+S^SyZi
*/ =aTv! 8</
publicclass Page { 1waTTT?"Ho
L}pt)w*V1j
/** imply if the page has previous page */ W@I|Q -
privateboolean hasPrePage; N <Xq]!
K-
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/** imply if the page has next page */ io8'g3<
privateboolean hasNextPage; ] &Rx@&e*
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/** the number of every page */ #*UN >X
privateint everyPage; $[a8$VY^Cm
0a XPPnuX
/** the total page number */ ^0\
privateint totalPage; SR|`!
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/** the number of current page */ ] [p>Y>:b-
privateint currentPage; ~XmLX)vO/
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/** the begin index of the records by the current Yz+ZY
t!_<~
query */ )O@]uY
privateint beginIndex; |}di&y@-JI
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/** The default constructor */ 4J/}]Dr5
public Page(){ N@Uy=?)ZJ
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} )x=1]T>v"'
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/** construct the page by everyPage sW'2+|3"
* @param everyPage +Z!)^j
* */ .Z
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public Page(int everyPage){ hRD=Y<>A
this.everyPage = everyPage; U!*M*s
} _)>_{Pm
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/** The whole constructor */ ,N]H dR
public Page(boolean hasPrePage, boolean hasNextPage, \=ux atw
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st:`y=F_
int everyPage, int totalPage, os:A]
int currentPage, int beginIndex){ S p;G'*g
this.hasPrePage = hasPrePage; Vg>dI&O
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; 8h*Icf
this.totalPage = totalPage; tnN.:%mZ
this.currentPage = currentPage; pUQ/03dp
this.beginIndex = beginIndex; K1+)4!}%U
} xg;+<iW
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/** ?IqQ-C)6D
* @return yy i#Mo
,
* Returns the beginIndex. _M`--.{\O[
*/ F`XP@Xx
publicint getBeginIndex(){ 9CWF{"
return beginIndex; zck#tht4
n
} RL@VSHXc
i%#+\F.&
/** UU;(rS/
* @param beginIndex "!ug_'VW
* The beginIndex to set. [6%VRqY
*/ ^cP!\E-^
publicvoid setBeginIndex(int beginIndex){ ;Q OBBF3HG
this.beginIndex = beginIndex; g"p%C:NN
}
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/** %,}A@H,
* @return 8QLj["
* Returns the currentPage. pz\
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*/ Bn#?zI
publicint getCurrentPage(){ j7$e28|_n
return currentPage;
!sQY&*
} ZojIR\F^
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/** v1+3}5b'uF
* @param currentPage wsZF;8u t
* The currentPage to set. \IV1j)I"u
*/ 0ghGBuv1s
publicvoid setCurrentPage(int currentPage){ }Qn&^[[miL
this.currentPage = currentPage; Dwr)0nk
} DEG[Z7Ju
M "p
/** ;=eDO(Ij
* @return dJeNbVd
* Returns the everyPage. )_syZ1j
*/ ; >hNt
publicint getEveryPage(){ &5fJPv &
return everyPage; c'>/
} f_jo+z{-ik
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/** PV'x+bN5
* @param everyPage 4sF"6+%5d
* The everyPage to set. m? J0i>H
*/ 4o
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publicvoid setEveryPage(int everyPage){ u~7hWiY<2
this.everyPage = everyPage; H]{v;;'~
} C*)3e*T*
GP!?^r:en
/** |[<_GQl
* @return U@_dm/;0&
* Returns the hasNextPage. EUD~CZhS"k
*/ ,
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publicboolean getHasNextPage(){ %p^wZtm
return hasNextPage; Xx."$l
} :DrWq{4
`w#Oih!6A|
/** v5!d$Vctu
* @param hasNextPage Y!~49<;
* The hasNextPage to set. $+8cc\fq
*/ Pk{_(ybaY
publicvoid setHasNextPage(boolean hasNextPage){ =9y[1t
this.hasNextPage = hasNextPage; LSa,1{
} p4.wh|n
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/** 2,$8icM
* @return $2oTkOA
* Returns the hasPrePage. "bFTk/
*/ &gVN&
publicboolean getHasPrePage(){ we~[ ]
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return hasPrePage; :q$.,EZ4#n
} 0%9 q8M;
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/** j"ThEx0
* @param hasPrePage lGPUIoUo
* The hasPrePage to set. Bn=by{i
*/ f2Klt6"9
publicvoid setHasPrePage(boolean hasPrePage){ mXRB7k
this.hasPrePage = hasPrePage; }iXDa?6%
} ZXqSH${Tp
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/** ]
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* @return Returns the totalPage. 6}gls}[0{e
* 1L%CJ+Q#0i
*/ 8##-EN;ag
publicint getTotalPage(){ #a/5SZP
Z\
return totalPage; 8{wwd:6
} 9oRy)_5Z(=
/[a~3^Gs^
/** q.KG^=10
* @param totalPage -[*,^Ti`
* The totalPage to set. SN9kFFIPb=
*/ m'Amli@[
publicvoid setTotalPage(int totalPage){ ''q@>
this.totalPage = totalPage; O,+1<.;+
} ~Sg5:T3
b*;Si7-
} 9oyE$S h]
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^ZvWR%
p#ol*m5wE
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 A_XY'z 1
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个PageUtil,负责对Page对象进行构造: e}D3d=6`
java代码: <":;+Ng+
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/*Created on 2005-4-14*/ <6EeD5{*
package org.flyware.util.page; :By?O"LQ
L6t+zIUc-~
import org.apache.commons.logging.Log; Vi>,kF.fV
import org.apache.commons.logging.LogFactory; TTeH`
n&{Dq}q
/** {'XggI%
* @author Joa R?GDJ3
* gQ o]
*/ ;\a
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publicclass PageUtil { %7"q"A r[
TC@s
privatestaticfinal Log logger = LogFactory.getLog Ee)T1~;W
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(PageUtil.class); X}=n:Ql'YY
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/** 3)F|*F3R
* Use the origin page to create a new page =!kk|_0%E
* @param page M`. tf_x
* @param totalRecords jlkmLcpf
* @return G<At_YS
*/ 0C =3dnp6
publicstatic Page createPage(Page page, int v/Py"hQ
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totalRecords){ 3/aMJR:o
return createPage(page.getEveryPage(), x*![fK
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page.getCurrentPage(), totalRecords); i'a?kSy
} .\[`B.Q
xAqb\|$^
/** YNLV9.P6
* the basic page utils not including exception K0H'4' I
NE"@Bk
cm
handler I3=%h
* @param everyPage ge,H-8'Z
* @param currentPage $:cE ^8K
* @param totalRecords tR}MrM
* @return page I~q#eO)
*/ r;/4F/6"
publicstatic Page createPage(int everyPage, int c2h{6;bfY
&qMPq->
currentPage, int totalRecords){ M2HomO/X)
everyPage = getEveryPage(everyPage); h XfQ)$J
currentPage = getCurrentPage(currentPage); H(R1o~
int beginIndex = getBeginIndex(everyPage, I
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VYu~26Zr
currentPage); qS403+Su1=
int totalPage = getTotalPage(everyPage, dq7x3v^"ZG
bHPYp5UwN
totalRecords); CUO+9X-<8
boolean hasNextPage = hasNextPage(currentPage, ^M3~^lV
)`SES."
totalPage); !Nu<xq@!
boolean hasPrePage = hasPrePage(currentPage); ?p9VO.^5
{!.(7wV\
returnnew Page(hasPrePage, hasNextPage, VO,!x~S!
everyPage, totalPage, RS"H8P4W
currentPage, e>7]w,*|
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beginIndex); )'Oh`$M
} $56Z#'(D
;,$NAejgd
privatestaticint getEveryPage(int everyPage){ O!zV)^r
return everyPage == 0 ? 10 : everyPage; B\<Q ;RI2;
} Ao&\E cIOT
, R'@%,/
privatestaticint getCurrentPage(int currentPage){ IC#>X5
return currentPage == 0 ? 1 : currentPage; IM:=@a{
} |M>eEE*F<
@.osJ}FxA
privatestaticint getBeginIndex(int everyPage, int oeKHqP wg
K\>tA)IPSV
currentPage){ kd=GCO
return(currentPage - 1) * everyPage; XUM!Qv
} VcAue!MN
*YW/_
privatestaticint getTotalPage(int everyPage, int stG~AC
8;z6=.4xtg
totalRecords){ IYqBQnX}oM
int totalPage = 0; ZtV9&rd7
]Oh@,V8
if(totalRecords % everyPage == 0) rFIqC:=
totalPage = totalRecords / everyPage; ^g*pGrl#
else \[BK1JP
totalPage = totalRecords / everyPage + 1 ; w<C#Bka
~u)}ScTp
return totalPage; ]p*l%(dhY
} V\6=ySx
VOKZ dC-
privatestaticboolean hasPrePage(int currentPage){ p%iGc<vHX
return currentPage == 1 ? false : true; `D>S;[~S7
} ~Cl){8o
'Hc-~l>D
privatestaticboolean hasNextPage(int currentPage, D5$wTI
Q<z_/j9
int totalPage){ ,%n\=
return currentPage == totalPage || totalPage == #?5 (o
8
![|F:
0 ? false : true; ,O.3&Nz,c
} CJ(NgYC h
0FGe=$vD
Uh.oErHQD
} y@ ML/9X8q
ykv94i?Q
2GFLnz
pM x
|B.0TdF
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。 _= +V/=
r9X?PA0f
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 Ae
mDJ8Y
J+[_Wd
做法如下: "nZ*{uv
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 wyp|qIS;
Q&MZN);.
的信息,和一个结果集List: 0*%Z's\M"
java代码: iDMJicW!+F
:r%P.60H X
D0g ZC
/*Created on 2005-6-13*/ ~}F{vm
package com.adt.bo; =Qh\D
NXwz$}}Pp
import java.util.List; km)zMoE{c{
zfI>qJ+Nqt
import org.flyware.util.page.Page; 8'~[pMn`
UjaK&K+M?
/** Dpvk\t
* @author Joa 0.dgoq3u
*/ +hn+K1
publicclass Result { @b"t]#V(E
xB_!>SqF1U
private Page page; }MRd@ 0-?!
MHSs!^/g5
private List content; tYZ[68
}Mo=PWI1?
/** _Xn qb+
* The default constructor Is]aj-#r
*/ ]GN7+8l
public Result(){ sW)Zi
super(); t0z!DOODZP
} ~(x;5{
T;@;R%
/** ,$1eFgY%
* The constructor using fields WtViW=j'
* RMd[Yr2e
* @param page N5* u]j
* @param content +u!0rLb
*/ XS`M-{f`
public Result(Page page, List content){ f~Fm4>\(
this.page = page; P/xKnm~
this.content = content; R16'?,
} XpmS{nb
!lEY=1nHOJ
/** >wb'QzF:
* @return Returns the content. SGh1 DB
*/ [!} :KD2yX
publicList getContent(){ /TZOJE(2j
return content; Qi_>Mg`x
} U Z.=aQ}M
(rkyW z
/** O<96/a'
* @return Returns the page. *:>"q ej
*/ mocI&=EF2X
public Page getPage(){ D@.tkzU@E
return page; 7h6,c /<
} VUVaaOmO
Ynp{u`?
/** ,oaw0Vw
* @param content z74in8]
* The content to set. ~vXaqCX
*/ =Vy`J)z9
public void setContent(List content){ 0GB:GBhZ
this.content = content;
=i_-F$pV
} v3}L`dyh3
Hu.t 3:w
/** ]4h92\\965
* @param page b7 !Qn}
* The page to set. r`AuvwHPs[
*/ 6b%WHLUeT
publicvoid setPage(Page page){ ^xh}I5
this.page = page; .mDM[e@'
} /I)yU>o
} 9so6WIWc
<Ard7UT
`D`sr[3n
[[>wB[w
x%+aKZ(m)
2. 编写业务逻辑接口,并实现它(UserManager, ?_"+^R z
j7sKsbb
UserManagerImpl) U>V&-kxtV
java代码: >=UF-xk;
Jd5:{{Lb
tjGd )
/*Created on 2005-7-15*/ OR}c)|1
package com.adt.service; '~ ,p[
][W_[0v
import net.sf.hibernate.HibernateException; K?s+ 3
FDVcow*] n
import org.flyware.util.page.Page; N@O8\oQG
3dht!7/
import com.adt.bo.Result; _<a7CCg
9uRFnzJVx
/** M9y<t'
* @author Joa TUHi5K
*/ wD68tG$
publicinterface UserManager { A|L 8P
slg ]#Dy
public Result listUser(Page page)throws HPb]Zj
Q3|T':l4
HibernateException; GP&vLt51
NZ/yBOD(
} Nluv/?<
{e+-vl
v2H#=E4cZ#
TF 'U
-RS7h
java代码: OCZ[D{i9@
x9x E&
ZO4*sIw%
/*Created on 2005-7-15*/ 5aln>1x>hn
package com.adt.service.impl; tZ `z
,WvY$_#xW%
import java.util.List; <Q?a=4
p/U+0f
import net.sf.hibernate.HibernateException; yaG= j
.&9 i
import org.flyware.util.page.Page; ]8T |f
import org.flyware.util.page.PageUtil; FXzFHU/dP
:6zG7qES3
import com.adt.bo.Result; %{/%mJoX
import com.adt.dao.UserDAO; xdf82)
import com.adt.exception.ObjectNotFoundException; NzU,va N
import com.adt.service.UserManager; mt5KbA>nU
/9zE^YcT
/** V5GW:QT
* @author Joa Tszp3,]f
*/ 34wkzu
publicclass UserManagerImpl implements UserManager { wE@'ap#
)(tM/r4`c&
private UserDAO userDAO; TQ`Rk;0R
'=1KVE^Fk
/** Q%wY
* @param userDAO The userDAO to set. {_Lgtu
*/ /v/C<]
publicvoid setUserDAO(UserDAO userDAO){ H"C[&r
this.userDAO = userDAO; {}QB|IH`
} `.T}=j|
8me ]JRw
/* (non-Javadoc) $&<uT
* @see com.adt.service.UserManager#listUser j'aHF#_
+V{7")px6
(org.flyware.util.page.Page) 8E4mA5@
*/ `2`\]X_A{
public Result listUser(Page page)throws E\IlF 6
!'j?.F$}
HibernateException, ObjectNotFoundException { 2*N_5&9mE
int totalRecords = userDAO.getUserCount(); '0\@Mc U]
if(totalRecords == 0) 4'6`Ll|iq
throw new ObjectNotFoundException o99pHW(E
WBN w~|DO]
("userNotExist"); >0dv+8Mn
page = PageUtil.createPage(page, totalRecords); M/q E2L[y
List users = userDAO.getUserByPage(page); ^{xeij/
returnnew Result(page, users); .[Ap=UYI>
} c-g)eV|)S
@FC"nM
} ' j6gG
9elga"4:'
OKi\zS
vTaJqEE
u~3%bJ]
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 vk>b#%1{
~}!3G
询,接下来编写UserDAO的代码: &q`q4g&7
3. UserDAO 和 UserDAOImpl: ,(.MmP`
java代码: MB%Q WU
6<N5_1
m$9w"8R
/*Created on 2005-7-15*/ u5~Ns&o&N
package com.adt.dao; quvanxV-L
Up:<=Kgci
import java.util.List; Gcb|W&
H*bs31i{
import org.flyware.util.page.Page; ALEnI@0
25NTIzI@@
import net.sf.hibernate.HibernateException; t=*@yQ
nB
yA)(*PFz
/** iA0q_( \X
* @author Joa mo1oyQg8
*/ nOQa_G]Gz
publicinterface UserDAO extends BaseDAO { zNY)'
7T"XPV|W6
publicList getUserByName(String name)throws rU;RGz6}
r1<F
HibernateException; y$3;$ R^
$5v0m#[^
publicint getUserCount()throws HibernateException; dJv!Dts')C
Oky**B[D'
publicList getUserByPage(Page page)throws FSRm|
u7xDau(c
HibernateException; +rIL|c}J
`;YU.*
} (ZL sB{r^
A>[|g`;t
`\X+ Ud|
3:{yJdpg
U~W?s(Cy%
java代码: k"g._|G
G[8in
49d@!
/*Created on 2005-7-15*/ U `o^mtW.
package com.adt.dao.impl; LGc&o]k
~>0qZ{3J_
import java.util.List; PlYm&
tX!nsm1
import org.flyware.util.page.Page; *xE,sj+(
>|6iR%"f#
import net.sf.hibernate.HibernateException; .))v0
import net.sf.hibernate.Query; +525{Tj
@Kf_z5tm:
import com.adt.dao.UserDAO; be e5
/T,Z>R
/** RUr=fEH
* @author Joa 6l$L~>
*/ BS&;n
public class UserDAOImpl extends BaseDAOHibernateImpl +fx8muz:y
zZiJ 9 e
implements UserDAO { &20P,8@
N)S!7%ne
/* (non-Javadoc) 341?0%=
* @see com.adt.dao.UserDAO#getUserByName U$H@ jJ*
# wc \T
(java.lang.String) ^FZ^6*
*/ Y%|@R3[Nk
publicList getUserByName(String name)throws eUl/o1~mXa
l{VSb92f
HibernateException { 'xv8Gwf"
String querySentence = "FROM user in class (_r EAEo
&TG5rUUg
com.adt.po.User WHERE user.name=:name"; /H:I 68~
Query query = getSession().createQuery KOg?FmD
83cW=?UgA
(querySentence); .D4bqL
query.setParameter("name", name); >xA),^ YT
return query.list(); W$qd/'%
} DFO7uw1
NZN-^ >
/* (non-Javadoc) ^v9|%^ug
* @see com.adt.dao.UserDAO#getUserCount() YpUp@/"
*/ $T<}y_nHl
publicint getUserCount()throws HibernateException { 5efxEt>U
int count = 0; g(O;{Q_
String querySentence = "SELECT count(*) FROM ;WT{|z
-Q;#sJ?
user in class com.adt.po.User"; +>7$4`Nb2
Query query = getSession().createQuery Y${l!+q
O[9-:,B{w
(querySentence); >)_ojDO
count = ((Integer)query.iterate().next 5]1leT
ec Oy6@UDY
()).intValue(); #Fu>|2F|
return count; .+y>8h3{
} Wk^RA_
l{ex?
/* (non-Javadoc) M }0eu(_|
* @see com.adt.dao.UserDAO#getUserByPage M,3wmW&d6
FFEfp.T1M
(org.flyware.util.page.Page) p.fF}B
*/ ED$DSz)x
publicList getUserByPage(Page page)throws BIf^~jAER%
~#}Dx
:HH
HibernateException { <DH*~tLp2
String querySentence = "FROM user in class i`)!X:j
tvX>{-M
com.adt.po.User"; G6K
<
Query query = getSession().createQuery [oc~iDx%W
<B /5J:o<
(querySentence); # x>g a
query.setFirstResult(page.getBeginIndex()) Rq~t4sA:
.setMaxResults(page.getEveryPage()); gM>=%/.
return query.list(); 4z:#I;
} `ya;:$(6
6@tvRDeaDW
} ]WJfgN4
IfDx@ ?OB
4c~>ci,N?(
PiLJZBUv
5/m$)wE
至此,一个完整的分页程序完成。前台的只需要调用 <-UOISyf
J
NC
userManager.listUser(page)即可得到一个Page对象和结果集对象 ^TXf sQs
Swtbl`,
的综合体,而传入的参数page对象则可以由前台传入,如果用 :9l51oE7
\g-j9|0
webwork,甚至可以直接在配置文件中指定。 p4VqV6LwD
LF*Q!
下面给出一个webwork调用示例: Oajv^H,Em
java代码: %Hi~aRz
BbJkdt7
v|
z08\a[
/*Created on 2005-6-17*/ %K 4
package com.adt.action.user; 2
Tvvq(?T
h5|.Et
import java.util.List; +rNkN:/L
TrE3S'EU#R
import org.apache.commons.logging.Log; YpdNX.P,
import org.apache.commons.logging.LogFactory; <XQ.A3SG!
import org.flyware.util.page.Page; <c,~aq#W'
c\cZ]RZ
import com.adt.bo.Result; MM{_Ur7Q
import com.adt.service.UserService; $2z
_{@Z
import com.opensymphony.xwork.Action; f?Bj _z
1
[z'G)v
/** h`MdKX$
* @author Joa NWmtwS+@
*/ 3+OsjZ
publicclass ListUser implementsAction{ PfW|77
S+x_c4 T
privatestaticfinal Log logger = LogFactory.getLog "oc$
FE5Q?*Ea
(ListUser.class); N4^5rrkL
0vs0*;F;
private UserService userService; 4cCF\&yU
O>DNC-m)i{
private Page page; =~FG&rk^
(N~$x
privateList users; ){Mu~P
SKXBrD=-
/* s<T?pH
* (non-Javadoc) ~waNPjPRG
* O ++/ry%k
* @see com.opensymphony.xwork.Action#execute() >kY p%r6
*/ RU!?-#*
publicString execute()throwsException{ PE@+w#i7*
Result result = userService.listUser(page); 7h<> k*E)
page = result.getPage(); 32XS`Z
users = result.getContent(); ^nDal':*
return SUCCESS; 6`nR5 fh
} gp< =Gmd
Jj"HpK>[
/** vahoSc;sw
* @return Returns the page. @YL}km&Fw
*/ wODvc9p}]
public Page getPage(){ hCc0sRp
return page; lxb 8xY
} QocQowz
D$Kea
/** H/cTJ9zz
* @return Returns the users. gT1P*N;v
*/ |'hLa
publicList getUsers(){ "G?9b
return users; oh}^?p
} -@bp4Z=
*v #/Y9}
/** i+(GNcg2
* @param page Dm{Ok#@r2
* The page to set. T |"`8mG
*/ r?p{LF
publicvoid setPage(Page page){ 9Vh_[^bR
this.page = page; .)PqN s:
} Cv TwBJy1
`^8*<+
/** Rl@$xP
* @param users -zC]^Ho@
* The users to set. hLuJWjCV
*/ yFeeG3n3
publicvoid setUsers(List users){ eK_*q-
this.users = users; ;) pl{_
} ~$aTM_4
n9}RW;N+u
/** |>utWT]S
* @param userService \|+/0USn
* The userService to set. >[3X]n,0
*/ uW[3G
publicvoid setUserService(UserService userService){ dtW0\^ .L
this.userService = userService; *TnzkNN_,
} nxRwWj57
} 8M93cyX
F'BdQk3o
%8D?$v"#Z
1X@b?6
A@ VaaX
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, @l>Xnqx)
w~-X>~ }
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 B7 c[4
.Ty,_3+{#p
么只需要: Vipp /WV
java代码: ,ep9V,+|
;X7i/DQ
j.&
;c'V$.
<?xml version="1.0"?> 8-A|C<
"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork SfDQ;1?
VK4/82@5
1.0//EN" "http://www.opensymphony.com/xwork/xwork- B)a@fmp"a
NV~vuC
1.0.dtd"> nEVbfNo0
JD&U}dJ
<xwork> lPS*-p#IZ
&7][@v
<package name="user" extends="webwork- /co%:}ln
j`9Nwa
interceptors"> 3H'*?|Y(#
FfXZ|o$;
<!-- The default interceptor stack name `vEqj v
DB8s
--> 1f;or_f#k?
<default-interceptor-ref UPO^V:.R4
ysth{[<5F3
name="myDefaultWebStack"/> )*HjRTF6G
3ZN>9`
<action name="listUser" hho%~^bn(
jZ#UUnR%
class="com.adt.action.user.ListUser"> =c]a
{|W?
<param )[
b#g(Y(
A;t
zRe
name="page.everyPage">10</param> ~,Mr0
<result xppkLoPK
; +9(;
name="success">/user/user_list.jsp</result> EE9vk*[@C
</action> 3{q[q#"
`oPLl0
</package> O\JD, w
a
8-;
</xwork> $kv[iI@
9<Ag1l
z5ZKks
C2.W[T
jMqx
F,.Q|.nN
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 *I/A,#4r
w>vmF cp
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 fO+UHSC
u#!GMZJN
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ;"SZ}
`$f2eB&
%t{Sb4XZ4k
^\{J5
~zj"OG"zOw
我写的一个用于分页的类,用了泛型了,hoho &/DOO ^
jQs*(=ls
java代码: Z?C4a}
w Oj88J)
>\&= [C
package com.intokr.util; V0S6M^\DK
Z !Z,M' "
import java.util.List; F`3^wHw^
QSv^l-<
/** lT3|D?sF
* 用于分页的类<br> 5Abz5-^KH
* 可以用于传递查询的结果也可以用于传送查询的参数<br> l\Cu1r-z
* *bU% @O
* @version 0.01 ik1XGFy?
* @author cheng ?4MSgu
*/ 15JsmA*Q
public class Paginator<E> { Vp\80D&
privateint count = 0; // 总记录数 *f?S5.
privateint p = 1; // 页编号 o[n<M>@
privateint num = 20; // 每页的记录数 qr9Imr0w<
privateList<E> results = null; // 结果 !^]q0x
/Go>5B>
/** |[DV\23{G
* 结果总数 v10mDr
*/ (<
:mM
publicint getCount(){ |;~nI'0O])
return count; p!QR3k.9s
} 5'62ulwMP=
NQg'|Pt(%
publicvoid setCount(int count){ b24di
this.count = count;
wFp~
} 2*Va9HP!q
f@h2;An$w
/** ['?^>jfr
* 本结果所在的页码,从1开始 48:liR
* xSdN5RN
* @return Returns the pageNo. K_Z+]]$#
*/ Z~:/#?/
publicint getP(){ @|E;}:?u
return p; Lp!0H `L
} |$Qp0vOA}
,RR;VKj
/** ,cPkx~w0
* if(p<=0) p=1 [6G=yp
* {uEu>D$8
* @param p Lblet
*/ J-b~4
publicvoid setP(int p){ %l%=Dkss
if(p <= 0) 6W]OpM
p = 1; 7KeXWW/ d
this.p = p;
!,Qm
} SQKi2\8w
%7iUlO}}V
/** :a=ro2NH
* 每页记录数量 N/(ofy
*/ @Jkui
publicint getNum(){ E7k-pquvE
return num; 5Ws5X_?d
} 1bT'u5&
]!]`~ Z/
/** qwL0~I
* if(num<1) num=1 Nz3zsP$
*/ sWp{Y.
publicvoid setNum(int num){ f%vHx,
if(num < 1) =_K%$y*
num = 1; G~JCgi
this.num = num; _'H2>V_
} ^6ExW>K
PG\\V$}A(
/** 'uws
* 获得总页数 ,\BfmC_i
*/ 2;dM:FHLhO
publicint getPageNum(){ 7qW.h>%WE
return(count - 1) / num + 1; @gs26jX~2}
} 37J\i ]
0Ddn@!J*
/** u4go*#
* 获得本页的开始编号,为 (p-1)*num+1 }~myf\$
*/ <ur KIu
publicint getStart(){ T_3V/)%@
return(p - 1) * num + 1; }P05eI
} Fsnw3/Nr
3s3a>
/** 58M'r{8_
* @return Returns the results. I[tAT[ <
*/ s4!|v`+$M
publicList<E> getResults(){ Ti0
(VdY
return results; ac2}3$u
} N;e;4,_ n
rdORNlK&
public void setResults(List<E> results){ s4MNVT
this.results = results; _K
4eD.
} emGV]A%nss
$ iX^p4v
public String toString(){ R
tXF
StringBuilder buff = new StringBuilder nL 1IS
Bq~AU#
(); \W3+VG2cA
buff.append("{"); s#'|{
buff.append("count:").append(count); "r5'lQI
buff.append(",p:").append(p); 0L3Bo3:k
buff.append(",nump:").append(num); *uk\O]
buff.append(",results:").append jrDz7AfA
qkIA,Kgy
(results); q$e
T!'x
buff.append("}"); MAsWds`bpB
return buff.toString(); u.ULS3`C/X
} f]@[4<N y
},?-$eyX
} 7H8GkuO
44Seq
Y!K^-Y}