Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 mjO4GpG3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 |&eZ[Sy(=l
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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 <e-9We."
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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 Y!c
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分页支持类: ,#hS#?t
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java代码: }-?_c#G3
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package com.javaeye.common.util; 3[B*l@}j
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import java.util.List; |Wd]:ijJ
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publicclass PaginationSupport { r1b{G%;mJ
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publicfinalstaticint PAGESIZE = 30; 8!2NZOZOS
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privateint pageSize = PAGESIZE; pp@Jndlg
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privateList items; .lAqD-
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privateint totalCount; dP63bV
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privateint[] indexes = newint[0]; 1wP#?p)c
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privateint startIndex = 0; rCU f,)
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public PaginationSupport(List items, int !`"@!
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totalCount){ Kq#\P
setPageSize(PAGESIZE); >a7OE=K
setTotalCount(totalCount); 8dgI&t
setItems(items); /?uA{/8
setStartIndex(0); JJ`RF
} I4{uw ge
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public PaginationSupport(List items, int c]LE9<G
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totalCount, int startIndex){ 4>eY/~odq]
setPageSize(PAGESIZE); !)gTS5Rh:
setTotalCount(totalCount); B64L>7\>`
setItems(items); ,<R/jHZP9
setStartIndex(startIndex); 0NrUB
} C1&~Y.6m
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public PaginationSupport(List items, int {`?C5<r
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totalCount, int pageSize, int startIndex){ %EkV-%o*
setPageSize(pageSize); =?g26>dYo
setTotalCount(totalCount); Z-X(.Q
setItems(items); qn)
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setStartIndex(startIndex); 6-#<*Pg
} (3a]#`Q
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publicList getItems(){ Dx`-Kg_p
return items; 8g0By;h;
} g}
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publicvoid setItems(List items){ =j#1HI=Fe
this.items = items; [&12`!;j
} l2H-E&'=
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publicint getPageSize(){ 4M4Y2fBH
return pageSize; DP{kin"4I
} K8`Jl=}z%&
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publicvoid setPageSize(int pageSize){ $>Md]/I8
this.pageSize = pageSize; wJ#fmQXKJ5
} WqQAt{W/<
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publicint getTotalCount(){ n7-|\p!xP6
return totalCount; z
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} )H=}bqn
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publicvoid setTotalCount(int totalCount){ ~nYp*t C'
if(totalCount > 0){ BkywYCWZ )
this.totalCount = totalCount; |dNJx<-
int count = totalCount / FvpaU\D
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pageSize; @CGci lS=
if(totalCount % pageSize > 0) yQ$Q{,S9
count++; |NuX9!S
indexes = newint[count]; ueI1O/Mi
for(int i = 0; i < count; i++){ Su"9`
indexes = pageSize * T%0vifoQ_$
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i; I
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} V9aGo#
}else{ iA*^`NMaT
this.totalCount = 0; 99W-sV
} pc9m,?n
} m#
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publicint[] getIndexes(){ ^3~+| A98M
return indexes; 2J7=
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} bm/pLC6%.
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publicvoid setIndexes(int[] indexes){ X S:W{tL!
this.indexes = indexes; X}"Ic@8
} "rxhS;
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publicint getStartIndex(){ tYb8a
return startIndex; >4I,9TO
} Gg'sgn
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publicvoid setStartIndex(int startIndex){ |5J'`1W
if(totalCount <= 0) GxH]
this.startIndex = 0; o8<0#W@S
elseif(startIndex >= totalCount) b!(ew`Y;
this.startIndex = indexes rq#8}T>
]rwHr;.
[indexes.length - 1]; 4I"%GN[tA
elseif(startIndex < 0) z"7I5N
this.startIndex = 0; BhAWIH8@C
else{ M$Sq3m`{!
this.startIndex = indexes k OYF]^uJ
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[startIndex / pageSize]; I^}q;L![\
} ++>HU{
} <jt_<p
+
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publicint getNextIndex(){ #kGgzO
int nextIndex = getStartIndex() + U`)\|\NY
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pageSize; ?+3vK=Rf}
if(nextIndex >= totalCount) hY*ylzr83
return getStartIndex(); qKt*<KGeY
else kHWW\?O
return nextIndex; 2EO WbN}M
} O_v8R7 {
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - y4N8B:j%
]|H`?L
pageSize; K)ZW1d;
if(previousIndex < 0) h?Y->!'
return0; 11"- taWj
else /#<R
return previousIndex; sxG8jD
} +,;"?j6<p
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} 1w`]2
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抽象业务类 o*]Tqx
java代码: W;Pdbf"
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/** i}tBB~]
* Created on 2005-7-12 9N+3S2sBx&
*/ =D>,s)}o3;
package com.javaeye.common.business; QD8.C=2R
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import java.io.Serializable; VtTTvP3
import java.util.List; Ym% $!#
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import org.hibernate.Criteria; `7D]J*?`
import org.hibernate.HibernateException; Jn|sS(Q}
import org.hibernate.Session; l+ ,p=
import org.hibernate.criterion.DetachedCriteria; Ux/|D_rlf
import org.hibernate.criterion.Projections; lmGVSdo
import mM[KT}
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org.springframework.orm.hibernate3.HibernateCallback; :eH*biXy}2
import CI#6r8u
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org.springframework.orm.hibernate3.support.HibernateDaoS QLPb5{>KDS
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upport; ~vb yX
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import com.javaeye.common.util.PaginationSupport; {+3
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public abstract class AbstractManager extends u# TNW.
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HibernateDaoSupport { -$ VP#%
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privateboolean cacheQueries = false; [
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privateString queryCacheRegion; |#b]e|aP
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publicvoid setCacheQueries(boolean mi';96
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cacheQueries){ >fq]c
this.cacheQueries = cacheQueries; sQ}E4Iq1#S
} *2T"lpl
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publicvoid setQueryCacheRegion(String )K}-z+$)k
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queryCacheRegion){ ufF>I
this.queryCacheRegion = L*8U.{NY
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queryCacheRegion; mEZHrr J
} Ueb&<tS
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publicvoid save(finalObject entity){ ^\f1zg9I
getHibernateTemplate().save(entity); hNRN`\5Z
} mXPA1#qo
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publicvoid persist(finalObject entity){ {aVRvZH4
getHibernateTemplate().save(entity);
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} Ql1J?9W
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publicvoid update(finalObject entity){ si,)!%b
getHibernateTemplate().update(entity); Ylhy Z&a,
} zl3GWj|?\7
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publicvoid delete(finalObject entity){ =j"bLX6;
getHibernateTemplate().delete(entity); _2a)b(<tF
} *-';ycOvr
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publicObject load(finalClass entity, ~( ;HkT
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finalSerializable id){ -`A+Qp)
return getHibernateTemplate().load 8yC/:_ML
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(entity, id); *}'3|e4w}
} Qx_]oz]NY
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publicObject get(finalClass entity, 8Q(A1U
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finalSerializable id){ u_=^Bd
return getHibernateTemplate().get 8~}~d}wW
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(entity, id); JKF/z@Vbe\
} pt%*Y.)az
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publicList findAll(finalClass entity){ )tv~N7
return getHibernateTemplate().find("from =.]{OT
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" + entity.getName()); -y'tz,En.
} w+Y_TJ%
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publicList findByNamedQuery(finalString 2w;Cw~<=d
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namedQuery){ 0<)Ep~!
return getHibernateTemplate [85b+SKW
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().findByNamedQuery(namedQuery); lyzM?lK-
} .3CQFbHF
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publicList findByNamedQuery(finalString query, (-Qr.t_B`
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finalObject parameter){ O&
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return getHibernateTemplate 'x,6t66*"l
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().findByNamedQuery(query, parameter); lxfv'A
} 8K9RA<
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publicList findByNamedQuery(finalString query, =>-W!Of
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finalObject[] parameters){ s[;1?+EI
return getHibernateTemplate "9IR|
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().findByNamedQuery(query, parameters); pD]2.O
} q\/xx`L
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publicList find(finalString query){ mYFc53B
return getHibernateTemplate().find ?!u9=??
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(query); s{:Thgv,9
} |*g\-2j{
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publicList find(finalString query, finalObject sitgz)Ki^
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parameter){ 7|k2~\@q
return getHibernateTemplate().find e\._M$l
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(query, parameter); l%
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} N>w+YFM
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public PaginationSupport findPageByCriteria 7[1VFc#tf
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(final DetachedCriteria detachedCriteria){ >@EwfM4[e
return findPageByCriteria }_D{|!!!T
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); j>3Fwg9V
} bsc#Oq]
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public PaginationSupport findPageByCriteria \j4!dOGZ
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(final DetachedCriteria detachedCriteria, finalint @QDUz>_y
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startIndex){ USJ4Z
return findPageByCriteria I:WPP'L4o
a1x].{
(detachedCriteria, PaginationSupport.PAGESIZE, v8TNBsEL
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startIndex); k>=wwPy
} >:OP+Vc
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public PaginationSupport findPageByCriteria P]7s1kgaS
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(final DetachedCriteria detachedCriteria, finalint AD>/#Ul
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pageSize, s>=$E~qq
finalint startIndex){ f[q_eY
return(PaginationSupport) (`<B#D;
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getHibernateTemplate().execute(new HibernateCallback(){ Z
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publicObject doInHibernate Ch]q:o4
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(Session session)throws HibernateException { F.D6O[pZ
Criteria criteria = }OSf C~5P
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detachedCriteria.getExecutableCriteria(session); [OFT!=.y &
int totalCount = t&-c?&FO\;
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((Integer) criteria.setProjection(Projections.rowCount D=)qd@,K
ie/QSte
()).uniqueResult()).intValue(); N@"e^i
criteria.setProjection {JM3drnw
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(null); )O\l3h"
List items = +B7UGI
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criteria.setFirstResult(startIndex).setMaxResults _+gpdQq\p
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(pageSize).list(); V/ZWyYxjLi
PaginationSupport ps = @^`5;JiUk
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new PaginationSupport(items, totalCount, pageSize, (A;HB@)[A
]@qD4:
startIndex); [n +(
return ps; xRF_'|e
} ?h8/\~Dw
}, true); P.~sNd oJ
} FWo`oJeN
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public List findAllByCriteria(final 7>gW2m
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DetachedCriteria detachedCriteria){ t5QGXj
return(List) getHibernateTemplate FYK}AR<=
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().execute(new HibernateCallback(){ %Ip=3($Ku[
publicObject doInHibernate /Wy9".
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(Session session)throws HibernateException { "?YpF2pD
Criteria criteria = 'IER9%V$
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detachedCriteria.getExecutableCriteria(session); ~'):1}KN]
return criteria.list(); 'v@1_HHW\
} ;e~K<vMm;y
}, true); o#IWH;ck.
} vw` '9~
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public int getCountByCriteria(final hflDVGBW
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DetachedCriteria detachedCriteria){ l_x>.' a
Integer count = (Integer) h#8{fr)6
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getHibernateTemplate().execute(new HibernateCallback(){ U7G|4(
publicObject doInHibernate !" : arK
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(Session session)throws HibernateException { &J=x[{R
Criteria criteria = S*rc XG6Q^
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detachedCriteria.getExecutableCriteria(session); gOk^("@
return ,0$b8lb;x/
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criteria.setProjection(Projections.rowCount OL[_2m*;9p
q{.~=~
()).uniqueResult(); QpifO
} 2K'}Vm+
}, true); ^[zF IO
return count.intValue(); l1RFn,Tzr
} {K2F(kz?T
} " 2@Ys*e
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用户在web层构造查询条件detachedCriteria,和可选的 M~!LjJg;
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 m<22E0=g
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PaginationSupport的实例ps。 @aGS~^Uh
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ps.getItems()得到已分页好的结果集 wmPpE_{
ps.getIndexes()得到分页索引的数组 JGk,u6K7
ps.getTotalCount()得到总结果数 )^'wcBod,
ps.getStartIndex()当前分页索引 ZZ6F0FLXJ
ps.getNextIndex()下一页索引 O4 Y;
ps.getPreviousIndex()上一页索引 Va'K~$d_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 >:P3j<xTv
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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 ^A$~8?f
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一下代码重构了。 1vxh3KS.
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我把原本我的做法也提供出来供大家讨论吧:
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首先,为了实现分页查询,我封装了一个Page类:
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java代码: iJE|u
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/*Created on 2005-4-14*/ VVje|T^{Z
package org.flyware.util.page; `o*g2fW!
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/** egi?Qg
* @author Joa G8?<(.pi@
* W.,J'
*/ efP2 C\
publicclass Page { am05>c9
i&FC-{|Z
/** imply if the page has previous page */ QX~*aqS3s8
privateboolean hasPrePage; Ic&t_B*i}]
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/** imply if the page has next page */ ?8C+wW
privateboolean hasNextPage; M !OI :v
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/** the number of every page */ 49Ue2=PP#
privateint everyPage; @kwD$%*0
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/** the total page number */ 6YU2
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privateint totalPage; C5RDP~au
uf)W?`e~
/** the number of current page */ L ou4M
privateint currentPage; :7>Si%
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/** the begin index of the records by the current 7<^D7
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query */ nZ7v9o9
privateint beginIndex; M7Hk54U+t
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/** The default constructor */ =3SL&
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public Page(){ 83l)o$S
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} iK%Rq
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/** construct the page by everyPage r IK|} 5
* @param everyPage ZJ[ Uz_%W
* */ OEwfNZQ-
public Page(int everyPage){ BtHvfoT
this.everyPage = everyPage; JN KZ'9
} F5<{-{Ky
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/** The whole constructor */ M<~F>(wxA
public Page(boolean hasPrePage, boolean hasNextPage, NxX1_d
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int everyPage, int totalPage, usTCn3u
int currentPage, int beginIndex){ V!<#E)-?<
this.hasPrePage = hasPrePage; l*:p==
this.hasNextPage = hasNextPage; S8)awTA9
this.everyPage = everyPage;
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this.totalPage = totalPage; 3MzY]J
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this.currentPage = currentPage; M7>\Qk
this.beginIndex = beginIndex; [sk"2
} _gGy(`
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/** L2h+[f
* @return 99:L#0!.W
* Returns the beginIndex. }b^lg&$(
*/ )eV40l$
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publicint getBeginIndex(){ w9PY^U.Y3e
return beginIndex; ::`j@ ]
} GQZUC\cB
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/** j5)qF1W,
* @param beginIndex 7=AKQ7BB>b
* The beginIndex to set. vZDQ@\HrC
*/ ,`7GI*Vq
publicvoid setBeginIndex(int beginIndex){ >PJ-Z~O'
this.beginIndex = beginIndex; 5k(#kyP
} 68!fcK
j&mL]'Zy
/** PYf`a`dH
* @return dbXG?K][
* Returns the currentPage. mHMej@
*/ vPsX!m[#
publicint getCurrentPage(){ KE3v3g<
return currentPage; dCK-"#T!
} HY:@=%R
|#B"j1D,H
/** 7A|jnm
* @param currentPage 4>E2G:
* The currentPage to set. t;1NzI$^
*/ ~GeYB6F
publicvoid setCurrentPage(int currentPage){ ^>p [b
this.currentPage = currentPage; ]x G4T>S
} %dU}GYL_
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/** eBV{B70k
* @return 7| T:TbY>
* Returns the everyPage. ^Bb_NcU
*/ HW G~m:km
publicint getEveryPage(){ S_CtEM
return everyPage; vSA%A47G
} FTfA\/tl(;
/fq6-;co+
/** PS22$_}
* @param everyPage ("oA{:@d
* The everyPage to set. 0R]CI
*/ bsry([N>w
publicvoid setEveryPage(int everyPage){ A!kyga6F5
this.everyPage = everyPage; Mt Z(\&~
} ,H?p9L; qp
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/** {\&"I|dpe
* @return f)x}_dw%
* Returns the hasNextPage. zOOX>3^
*/ iFA"m;$
publicboolean getHasNextPage(){ -!cAr
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return hasNextPage; b9N4Gr
} o%%fO
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/** Mg$9'a"[\
* @param hasNextPage >i%w'uU
* The hasNextPage to set. 0d ->$gb
*/ eNFUjDm
publicvoid setHasNextPage(boolean hasNextPage){ ODEXQl}R
this.hasNextPage = hasNextPage; wjJ1Psnx
} '5U$`Xe1
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/** m4wTg
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* @return ["<(\v9P)
* Returns the hasPrePage. jTr4A-"
*/ ;NeP&)Td
publicboolean getHasPrePage(){
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return hasPrePage; ha=z<Q
} =>
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/** g4~qcI=a
* @param hasPrePage I)6Sbt JV^
* The hasPrePage to set. #L0I+ K,K\
*/ I uj=d~|>
publicvoid setHasPrePage(boolean hasPrePage){
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this.hasPrePage = hasPrePage; B7MW" y
} \cP'#jZz
}GDG$QI]K&
/** !nq\x8nU
* @return Returns the totalPage. 0Zh
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* f](uc(8Z
*/ :5{@*
publicint getTotalPage(){ k)V%.Eobf
return totalPage; &2=KQ\HO
} d %W}w.
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/** AsLjU#jn
* @param totalPage ;-GzGDc~0
* The totalPage to set. pHB35=p28
*/ y9li<u<PF
publicvoid setTotalPage(int totalPage){ Xb-c`k~_
this.totalPage = totalPage; ,nR8l
} D(6x'</>?
}~r6>7I
} X,+}syK
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KR(} A"
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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 v-fi9$#^
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个PageUtil,负责对Page对象进行构造: hO.G'q$V
java代码: d5"EvT
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/*Created on 2005-4-14*/ n qLAby_
package org.flyware.util.page; `F\:XuY
mv*T=N8fC
import org.apache.commons.logging.Log; kj!7|1i2
import org.apache.commons.logging.LogFactory; Au} ;z6k
^;$a_$|
/** ]Y&)98
* @author Joa |;9 A{#zM
* _G[I2]
*/ *;e@t4
publicclass PageUtil { ;c-
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2{B(j&{
privatestaticfinal Log logger = LogFactory.getLog ]p&< nK,
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(PageUtil.class); Vt=(2d5:p
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/** V9j1j}
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* Use the origin page to create a new page A1QI4.K
* @param page 3E}NiD\V}
* @param totalRecords j8Q5d`
* @return u] U)d$|
*/ 9jR[:[
publicstatic Page createPage(Page page, int 8$v zpu
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totalRecords){ D5!K<G?-K
return createPage(page.getEveryPage(), %7>AcTN~
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Mh)
page.getCurrentPage(), totalRecords); CQjZAv
} [s{r$!Gl
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/** 25a#eDbqi
* the basic page utils not including exception PIEW \i
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handler "bR'Bt
* @param everyPage |\%F(d330
* @param currentPage '"w}gx
* @param totalRecords mKq<'t]^k
* @return page ]\RSHz
*/ {LT4u]#
publicstatic Page createPage(int everyPage, int _TOi
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currentPage, int totalRecords){ ri<'-w i
everyPage = getEveryPage(everyPage); ?D(FNd
currentPage = getCurrentPage(currentPage); L+L"$
int beginIndex = getBeginIndex(everyPage, `Ixs7{&jU
#K#Mv/
currentPage); -|Yh/
int totalPage = getTotalPage(everyPage, +t>*l>[
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totalRecords); 6c2ThtL
boolean hasNextPage = hasNextPage(currentPage, n4WSV
YO(:32S
totalPage); p584)"[*t
boolean hasPrePage = hasPrePage(currentPage); I[=Wmxa?r
nGx ~)T
returnnew Page(hasPrePage, hasNextPage, 9eGCBVW:*
everyPage, totalPage, ?UZ$bz
currentPage, :_^0'ULP
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beginIndex); wrQydI
} ]M~8@K
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privatestaticint getEveryPage(int everyPage){ i0'Xy>l
return everyPage == 0 ? 10 : everyPage; U+.PuC[3
} .>kccLr:z
t}]9VD9
privatestaticint getCurrentPage(int currentPage){ c>S"`r
return currentPage == 0 ? 1 : currentPage; >G<\1R
} Na.
nA
TZh\#dp4l
privatestaticint getBeginIndex(int everyPage, int 6;
5)/ q
n9kd2[s|
currentPage){ |7QVMFZ
return(currentPage - 1) * everyPage; E 4='m
} p*pn@z
Iys6R?~
privatestaticint getTotalPage(int everyPage, int HZDk
<aU/!
%Lp2jyv.
totalRecords){ MUbhEau?
int totalPage = 0; 5;FP.{+
FgOUe
if(totalRecords % everyPage == 0) *MYt:ms
totalPage = totalRecords / everyPage; (|g").L
else >`hSye{
totalPage = totalRecords / everyPage + 1 ; Gva}J6{
?eL='>Ne
return totalPage; pXPqDA
} j6tP)f^tD
m\6SG' X
privatestaticboolean hasPrePage(int currentPage){ =$b-xsmeG
return currentPage == 1 ? false : true;
09
} H\)gE>
_kn]#^ucCe
privatestaticboolean hasNextPage(int currentPage, +P[88!
u?q&K|
int totalPage){ Zk]k1]u*5
return currentPage == totalPage || totalPage == 6sYV7w,'@
.-.q3ib
0 ? false : true; j7@!J7S
} ljup#:n
nU}~I)@V
V.;:u#{@-Q
} M4TrnZ1D}
qs!>tw
kF+ZW%6N
ra]!4Kd'
Q&u>7_, Du
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。 Az
U|p
MxY50^}(
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 tCZpfZ@+=
`GvA241
做法如下: tCWJSi`IJ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 <^#P6
cwu$TP A>
的信息,和一个结果集List: 4-y6MH
java代码: RI(=HzB
7^B3lC)
`0yb?Nk `:
/*Created on 2005-6-13*/ g9DG=\*A
package com.adt.bo; U:qF/%w
?N4A9W9
import java.util.List; GS}0;x
so} l#
import org.flyware.util.page.Page; ;e&!
wX-RQ[2X
/** H \r `7
* @author Joa *I=_*LoG2
*/ -"F0eV+y
publicclass Result { nc<qbN
%v]7BV^%6
private Page page; clHM8$
ha_@Yqgh
private List content; IK8%Q(.c
L<0=giE
/** (.PmDBW
* The default constructor dF$KrwDK
*/ +d =~LQ}*
public Result(){ 2[.5o z`
super(); R @"`~#$$
} >[K0=nA
9#u }^t
/** {U(Bfe^a,
* The constructor using fields w]n4KR4
* .SG0}8gW
* @param page 9^oo-,Su_
* @param content y0;,dv]
*/ 8,=G1c
public Result(Page page, List content){ (%i!%{!]
this.page = page; =h(7rU"Yz
this.content = content; 7k>zuzRyF
} Q5g,7ac8L
bpGzTU
/** HP;|'b
* @return Returns the content. VR"8Di&)
*/ MM7"a?y)
publicList getContent(){ =Qyqfy*@D?
return content; 6mwvI4)
} #
2d,U\_
PDhWFF
/** r9?o$=T
* @return Returns the page. n-d:O\]
*/ NNgK:YibD
public Page getPage(){ $> ;a'f~
return page; $;y1Qiel
} Cgo9rC~]
gTnS[
/** oK)[p!D?0{
* @param content B0v|{C
* The content to set. fO#?k<p
*/ ,pn)>
public void setContent(List content){ 9MT3T?IS
this.content = content; 3#9uEDdE
} RXM}hqeG
am2a#4`
/** A$Wx#r7)
* @param page 0EyAMu
* The page to set. 691G15
*/ ]s_@n!
publicvoid setPage(Page page){ au}s=ua~i
this.page = page; "tKNlHBu'
} k9l^6#<?
} *=TYVM9
xLZ bU4
ZlrhC= 0
{(%~i37
!\ZcOk2
2. 编写业务逻辑接口,并实现它(UserManager, ( :iPm<
J=@xAVBc
UserManagerImpl) |f<9miNu
java代码: V7BsE w
f -7S:,
S4)A6z$
/*Created on 2005-7-15*/ kAeNQRjR
package com.adt.service; KYf;_C,$
fL2^\dB;
import net.sf.hibernate.HibernateException; !f`5B( @
g#}tm<
import org.flyware.util.page.Page; W=3? x
y=#j`MH{>
import com.adt.bo.Result; o ~;M"
@*SA$9/l
/** 2Q}7fht
* @author Joa 1#]B^D
*/ O~atNrHD
publicinterface UserManager { 7u|%^Ao6
{d,?bs)
public Result listUser(Page page)throws 3+%nn+m
z<i,D08|d
HibernateException; ;7L ;
3
&Sp@,
}
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|WBZN1W)
Z B$NVY
pu#[pa
2Y$
java代码: BtzYA"
a>w~FUm*
@gEr+O1K(
/*Created on 2005-7-15*/ xvB8YW"
package com.adt.service.impl; q=+wI"[
.'&V#D0
import java.util.List; %XR<isn
~TM>"eB b
import net.sf.hibernate.HibernateException; -zdmr"CA
PV(4$I}
import org.flyware.util.page.Page; 5/,Qz>QE[
import org.flyware.util.page.PageUtil; _-RyHgX
8RU.}PD
import com.adt.bo.Result; n>S2}y
import com.adt.dao.UserDAO; bM ^7g
import com.adt.exception.ObjectNotFoundException; ~3d*b8
import com.adt.service.UserManager; FllX za)
`6}Yqh))
/** 5#2jq<D
* @author Joa #Skj#)I"
*/ v1h.pbz`w
publicclass UserManagerImpl implements UserManager { DL1
+c`d
l|7O)
private UserDAO userDAO; ;P8(Zf3wJb
~2(]ZfO?>H
/** %i595Ij-]
* @param userDAO The userDAO to set. %jTw
*/ +!><5
publicvoid setUserDAO(UserDAO userDAO){ op.d;lO@
this.userDAO = userDAO; ly=a>}F_
} H#`8Ey
#N$9u"8C
/* (non-Javadoc) \C7q4p?8
* @see com.adt.service.UserManager#listUser CbQ4Y
) $J7sa
(org.flyware.util.page.Page) =9<$eLE0
*/ \?dTH:v/E
public Result listUser(Page page)throws nd.hHQ
7 OWsHlU
HibernateException, ObjectNotFoundException { #
M>wH`Q#
int totalRecords = userDAO.getUserCount(); +|0 t
if(totalRecords == 0) >:$"a
throw new ObjectNotFoundException x;(g
GMw)*
("userNotExist"); *Dc@CmBr
page = PageUtil.createPage(page, totalRecords); YD9!=a$
List users = userDAO.getUserByPage(page); X.eB ;w/}
returnnew Result(page, users); .`+yo0O:
} OJ>iq@>
WN\PX!K9
} a%*_2#
-K^41W71
tgB=vIw?3
+99Bi2H}o
QtlT&|$
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 *uU4^E(
y;QQ| =,
询,接下来编写UserDAO的代码: ^cn@?k((A
3. UserDAO 和 UserDAOImpl: #a'r_K=ch)
java代码: sG1BNb_
ST%
T =_q
mV;3ILO
/*Created on 2005-7-15*/ abSq2*5K
package com.adt.dao; [T]Bf o
5*+I
M*c
import java.util.List; gyFr"9';c
G
B&:G V
import org.flyware.util.page.Page; aj
v}JV&:
tah}^
import net.sf.hibernate.HibernateException; D2]ZMDL.
R;'?;I
/** )qd={
* @author Joa CIy^`2wq
*/ C`EY5"N r
publicinterface UserDAO extends BaseDAO { GW8CaTf~
2LZS|fB9o
publicList getUserByName(String name)throws MQ9vPgh
Qi^;1&
HibernateException; NWaO_sm
sv`"\3N[
publicint getUserCount()throws HibernateException; dN0mYlu1|
;W6-i2?
publicList getUserByPage(Page page)throws Vd<K4Tk
'kQ~
HibernateException; n.ct]+L
Z/h|\SyJ
} ONfyYM?
0Z8/R
)cKj iXn
UFf,+4q
#D0W7a
java代码: \HD-vINV;
N%*9&FjrL
r&Qt_
/*Created on 2005-7-15*/ b!,ja?
package com.adt.dao.impl; K"^cq~
;j!UY.i
import java.util.List; ^vW$XRnt
XmlIj8%9[&
import org.flyware.util.page.Page; #fj[kq)&S
@(){/cF
import net.sf.hibernate.HibernateException; KC]tY9 FK
import net.sf.hibernate.Query; H0+:XF\M
q0g1EJar
import com.adt.dao.UserDAO; eo ?Oir)
B/G3T
u uG
/** <p/MyqZf
* @author Joa -%i#j>
*/ "/!'9na{QL
public class UserDAOImpl extends BaseDAOHibernateImpl vnZ4(
|(&oI(l5K
implements UserDAO { Vmtzig3w[
bs P6\'\4
/* (non-Javadoc) ZMJ3NN]F
* @see com.adt.dao.UserDAO#getUserByName ydup)[n
{lMqcK
(java.lang.String) j-6v2MH
*/ 82s5VQ6
publicList getUserByName(String name)throws
pl?kS8#U?
k,lqT>C
HibernateException { -$9~xX
String querySentence = "FROM user in class yfC2^#9 Zu
rmQ\RP W
com.adt.po.User WHERE user.name=:name"; F+3!uWUK
Query query = getSession().createQuery }k| g%HJ
sjb-Me?
(querySentence); \imp7}N
query.setParameter("name", name); phmVkV2a;#
return query.list(); P#v^"}.Wd
} "f<#.}8
=1IEpxh%
/* (non-Javadoc) ?yf_Dt
* @see com.adt.dao.UserDAO#getUserCount() B>@D,)/bT5
*/ 9?(x>P
publicint getUserCount()throws HibernateException { T\fudmj&
int count = 0; Az9J\V~"
String querySentence = "SELECT count(*) FROM 8F)=n \
NA\ x<
user in class com.adt.po.User"; +[_gyLN<5b
Query query = getSession().createQuery ?R282l
#<UuI9
(querySentence); AoIc9ElEX
count = ((Integer)query.iterate().next u]0!|Jd0
zu<>"5}]
()).intValue(); :v#8O~
return count; ey*,StT5a
} 77tZp @>hn
]` K[W &
/* (non-Javadoc) <ZV7|'^
* @see com.adt.dao.UserDAO#getUserByPage 61kO1,Uz*
y}Cj#I+a
(org.flyware.util.page.Page) 0f{IE@-b
*/ C[g&F0 6
publicList getUserByPage(Page page)throws soDfi-2o3
Yx!n*+ :J
HibernateException { s<,"Hsh^CR
String querySentence = "FROM user in class QU,?}w'?d
y+= \z*9
com.adt.po.User";
ZRO.bMgZF
Query query = getSession().createQuery )Yrr%f`\
..aK sSm(
(querySentence); }FZp840
query.setFirstResult(page.getBeginIndex()) g&P9UW>qS
.setMaxResults(page.getEveryPage()); -: C[P
return query.list(); [RW,{A
} ;2BPPZ
f)WPOTEY
} pRmE ryR(U
sY_fq.Z
aC4m{F[
pIL`WE1'
*6'_5~G
至此,一个完整的分页程序完成。前台的只需要调用 hl}dgp((
[-QK$~[ g
userManager.listUser(page)即可得到一个Page对象和结果集对象 m8p4U-*j
h|)2'07
的综合体,而传入的参数page对象则可以由前台传入,如果用 9z5z
+Z]y #=
webwork,甚至可以直接在配置文件中指定。 Y[T J;O!R
95VqaR,
下面给出一个webwork调用示例: r^e-.,+
java代码: f&f[La
wH#Lb@cfZ0
|O2|`"7
/*Created on 2005-6-17*/ 31H|?cg<
package com.adt.action.user; ddl3fl#f
W%w82@'
import java.util.List; 7~:>WMv9
/oB K&r[(
import org.apache.commons.logging.Log; H_v/}DEG
import org.apache.commons.logging.LogFactory; gr[D!D>
import org.flyware.util.page.Page; i;gw=Be
-g~iE]x6Y
import com.adt.bo.Result; VB}P Ng
import com.adt.service.UserService; s9=pV4fA~w
import com.opensymphony.xwork.Action; O$YJku
!P+~c0DF
/** O'Vh{JHf
* @author Joa YstXNN4
*/ bl6':m+
publicclass ListUser implementsAction{ CRP7U
[@jp9D
H
privatestaticfinal Log logger = LogFactory.getLog @b4b{d5[
zR_9D}
(ListUser.class); ^o,y5,
m21QN9(i%
private UserService userService; L>eQ*311
I):m6y@
private Page page; _$~ex ~v
i_'|:Uy*F
privateList users; N.kuE=X
"bLP3
/* 2nVuz9h
* (non-Javadoc) 9*"[pt+tA
* W5M
]
* @see com.opensymphony.xwork.Action#execute() XT\Td}>
*/ 'cWlY3%t
publicString execute()throwsException{ # r2$ZCo3o
Result result = userService.listUser(page); m/SJ4op$
page = result.getPage(); ,%&
LG],6
users = result.getContent(); Aigcq38
return SUCCESS; \>&@lA
} V7qCbd^>XJ
1v+JCOy
/** t"jIfU>'a/
* @return Returns the page. EY=\C$3J:
*/ y=y/d>=w
public Page getPage(){ ,K"r:)\
return page; {b\Y?t^>f
} =P@M&Yy'
";%e~
=
/** hlYS=cgY=
* @return Returns the users. 7R%
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*/ $sB48LJuU'
publicList getUsers(){ My`josJ`Pb
return users; $fq-wl-=
} n3-GnVC][
4+Li)A:4.
/** p7?CeyZ-V
* @param page k:&?$
* The page to set. NXC~#oG
*/ S}XB
|
publicvoid setPage(Page page){ 1t}
(+NNjH
this.page = page; o+PQ;Dl
} HY@kw>I
8,Q.t7v
/** \rB/83[;u
* @param users z/Mhu{ttL
* The users to set. 9P,A
t8V(
*/ oRtY?6^$
publicvoid setUsers(List users){ bqf]$}/8k
this.users = users; %tklup]LF8
} ==r?
t6! p\Y}}
/** R(n0!h4
* @param userService ;@=@N9qK
* The userService to set. |1\dCE03}
*/ +3~Gc<OO
publicvoid setUserService(UserService userService){ giA~+m~fN
this.userService = userService; *;V2_fWJ@
} K{`2jK#
} S]#=ES'^/
;'Z,[ a
{!:|.!-u
P %U9S
6w:g77SH)%
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, -Lz1#S k]A
Z]1z*dv
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 A1=$kzw{UH
N'Z_6A*-
么只需要: GT1 X
java代码: |{}d5Z"5;}
?$`1%Y9
KqG$zC^N
<?xml version="1.0"?> `
i^`Q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ?()E5 4y
*n$m;yI
1.0//EN" "http://www.opensymphony.com/xwork/xwork- z!Pdivx
}hObtAS
1.0.dtd"> (pRy1DH~
Rzn 0-cG
<xwork> 8gu7f;H/k
#7cf 8y
<package name="user" extends="webwork- F(J!dG5#
'6Z/-V4k
interceptors"> Xbsj:Ko]]U
A<*tn?M]
<!-- The default interceptor stack name tZc.%TU
=":V
WHf
--> =."WvBKg
<default-interceptor-ref 5G42vTDzS4
p1`'1`.3
name="myDefaultWebStack"/> g en3"\Og{
7p"~:1hU
<action name="listUser" 6m;wO r
+ - KRp1qq
class="com.adt.action.user.ListUser"> <}x|@u
<param MIMPJXT#.
)MX1776kU
name="page.everyPage">10</param> 1dgN10
<result %lqG* dRx0
X
G@>1/
name="success">/user/user_list.jsp</result> pN^G[
</action> aGzdur
VHXR)}
</package> $4ZDT]n
m= beB\=
</xwork> _QtQPK\+
s'fcAh,c6
,a?\i
JNb
q_m#BE;t
WTy8 N
e[VJ0 A=
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 nH3b<k;S
JD\-X(O
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。
;] `NR
3Jk?)Dy
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 :N'[de
h}VYA\+<B
jJ{
w -$
iTBhLg,
^Ihdq89 t
我写的一个用于分页的类,用了泛型了,hoho @0@'6J04
"=5vgg3
java代码: <xh'@592
=ym~=
S
.qU%SmQ^
package com.intokr.util; Pt)}HF|u
6;=wuoJi
import java.util.List; mYs->mg1
G QB^
/** HI`A;G]
* 用于分页的类<br> d-S'y-V?d
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ''
A[`,3
* 1J%qbh
* @version 0.01 :R?| 2l
* @author cheng @BQBNGR 1
*/ gt~2Br4
public class Paginator<E> { `LHfAXKN
privateint count = 0; // 总记录数 4sD:J-c
privateint p = 1; // 页编号 +M%2m3.Jo
privateint num = 20; // 每页的记录数 !v;_@iW3e
privateList<E> results = null; // 结果 +H^V},dBp!
qFsg&<
/** o4
OEA)k)=
* 结果总数 Y
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*/ j!8+|eAkk
publicint getCount(){ {,mRMDEy
return count; v}*u[GWl]
} w!9W Cl]9M
"l;8
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publicvoid setCount(int count){ xTawG?"D
this.count = count; >yHnz?bf@
} !?-5hh1\
r#Oz0=0u
/** DO,&Foh\
* 本结果所在的页码,从1开始 S/:QVs
* >mDubP
* @return Returns the pageNo. s/&]gj"
*/ I!0+RP(
publicint getP(){ G78j$
^/0
return p; %_=R&m'n`
} U=#ylQ
Z1lF[d,f;
/** U\GZ
* if(p<=0) p=1 V4i%|vV
* N S}`(N
* @param p G(3la3\(
*/ E&tmWOMj>
publicvoid setP(int p){ DWxh{h">
if(p <= 0) }
K-[/;
p = 1; z7pXpy \
this.p = p; Z!l!3(<G.f
} 2}C>{*}yQ
J0W).mD_H
/** TK?+O}v-]!
* 每页记录数量 !OVEA^6
*/ kxf=%<l
publicint getNum(){ [cAg'R6
return num; k_^/
} _5`S)G{
%~(i[Ur;
/** X',0MBQ0
* if(num<1) num=1 q _|5,_a
*/ ?v~3zHK
publicvoid setNum(int num){ *pUV-^uo
if(num < 1) xVX||rrh
num = 1; ]c=1-Rl
this.num = num; 0BD((oNg
} (SVr>|Db
9+Hb`
/** D)Rf
* 获得总页数 0lh6b3tdP
*/ yC*B OJS
publicint getPageNum(){ 1)r _h(
return(count - 1) / num + 1; ^TuEp$Z=
} ]+7c1MB(5
O +}EE^*a
/** ]Wm ?<7H
* 获得本页的开始编号,为 (p-1)*num+1 &nw~gSe
*/ Ou,_l
publicint getStart(){ ZTC1t_
return(p - 1) * num + 1; z6r/
w
} ,PxQ[CGg
w o9f99
/** qyfxT Q5
* @return Returns the results. 3+uoK f[
*/ XB 7^Ka
publicList<E> getResults(){ uL AXN
return results; "
CoR?[,x
} ,]qX_`qF
.g?,:$`0D?
public void setResults(List<E> results){ !_!b\
this.results = results; C>VZf,JE1
} x}j41E}
^i1:PlW]
public String toString(){ Y &+/[[
StringBuilder buff = new StringBuilder *lO+^\HXD
TBT*j&!L
(); WfO$q^'?DP
buff.append("{"); CxQ,yd;>
buff.append("count:").append(count); Khd ,|pM
buff.append(",p:").append(p); Bz~h-
buff.append(",nump:").append(num); s\R?@
buff.append(",results:").append t+q`h3
E1g$WhXIS
(results); [&V%rhi
buff.append("}"); S6X<3L`FfH
return buff.toString(); Rx-i.Et Z
} zD-8#H35X"
PaJwM%s)L
} $O!<Zz
qEz'l'%(
P9wDTZ
:4