Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 v6+<F;G3y>
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #BX^"J{~
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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 pN7 v7rs
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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 F9C3i
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。 [;hCwj#
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分页支持类: Y!lc/[8
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java代码: dE|luN~
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package com.javaeye.common.util; PU^@BZ_m
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import java.util.List; Com`4>0>I
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publicclass PaginationSupport { UJ6zgsD1b?
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publicfinalstaticint PAGESIZE = 30; 9>HCt*|_8
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privateint pageSize = PAGESIZE; TGu]6NzyZ
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privateList items; ]*JH~.p
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privateint totalCount; HVK./yqy
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privateint[] indexes = newint[0]; |!H@{o
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privateint startIndex = 0; n0CS=
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public PaginationSupport(List items, int .q9wyVi7GI
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totalCount){ >PMLjXK
setPageSize(PAGESIZE); *IBCThj
setTotalCount(totalCount); k>q}: J9V
setItems(items); F 5FzT^
setStartIndex(0); qI#ow_lL#
} uV+.(sjH
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public PaginationSupport(List items, int 52d8EGC
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totalCount, int startIndex){ F_C_K"[s
setPageSize(PAGESIZE); KHJk}]K
setTotalCount(totalCount); #Do#e
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setItems(items); 2OQDG7#Kc
setStartIndex(startIndex); B!zqvShF
} cJ!C=J
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public PaginationSupport(List items, int yCG<qQz
@%sr#YqY
totalCount, int pageSize, int startIndex){ KK4"H]!.
setPageSize(pageSize); .WT^L2l%
setTotalCount(totalCount); kw.IVz<
setItems(items); hXx.
setStartIndex(startIndex); ?\$\YX%/p
} [.`%]Z(
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publicList getItems(){ Ps_q\R
return items; Z-B b,8
} &b7i> ()
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publicvoid setItems(List items){ C^ hCT
this.items = items; aR~Od Ys
} Oe[qfsdW
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publicint getPageSize(){ .&Ok53]b
return pageSize; xRU ~hQ
} 4%L-3Ij
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publicvoid setPageSize(int pageSize){ l`A4)8Y@
this.pageSize = pageSize; Lb}
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} ,dO$R.h
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publicint getTotalCount(){ XU19+mW=P
return totalCount; :u$+lq
} XTOZ]H*^
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publicvoid setTotalCount(int totalCount){ ';0NWFP
if(totalCount > 0){ +)gXU Vwd
this.totalCount = totalCount; gYy9N=f+
int count = totalCount / /P3s.-sL
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pageSize; }lzN)e
if(totalCount % pageSize > 0) ]9}T)Df'
count++; 9?_ybO~Oq
indexes = newint[count]; OnKPD=<
for(int i = 0; i < count; i++){ AZTn!hrU
indexes = pageSize * _p`@/[(|
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} &RP}w%I1
}else{ \1p5$0z
this.totalCount = 0; q
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} {UR&Y
} j2/3NF5&
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publicint[] getIndexes(){ 6(X5n5C
return indexes; >.-$?2
} t9Nu4yl
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publicvoid setIndexes(int[] indexes){ njy^<7;
this.indexes = indexes; V^U1o[`
} i!=28|_
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publicint getStartIndex(){ Dxwv\+7]
return startIndex; 0y3<Ho,+$
} i;Y@>-[e<
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publicvoid setStartIndex(int startIndex){ 7q] @Jx9
if(totalCount <= 0) k9^Vw+$m
this.startIndex = 0; X}5aE4K/
elseif(startIndex >= totalCount) d$G<g78D
this.startIndex = indexes @}e'(ju%R
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[indexes.length - 1]; 9A4h?/
elseif(startIndex < 0) @-ma_0cZQ
this.startIndex = 0; g#ZuRL
else{ !^|%Z
this.startIndex = indexes VnJ-nfA
ab=s+[r1
[startIndex / pageSize]; ;Q]j"1c
} %YaUc{.%
} ^3-Wxn9&
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publicint getNextIndex(){ L8~nx}UP5
int nextIndex = getStartIndex() + O&:0mpRZ
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pageSize; ClH aR
if(nextIndex >= totalCount) H<SL=mb;
return getStartIndex(); elgCPX&:W
else Iy}r'#N
return nextIndex; yMNLsR~ rh
} LxGE<xj|V%
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publicint getPreviousIndex(){ l}DCK
int previousIndex = getStartIndex() - IKK<D'6
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pageSize; S%ri/}qI[{
if(previousIndex < 0) h]94\XQ>$
return0; vl@t4\@3
else 1 ]@}+H
return previousIndex; 9@yP;{Q
} p0.?R
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} $l&&y?()
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抽象业务类 G5Ci"0
java代码: 1q!JpC^
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/** y0qE::/H$
* Created on 2005-7-12 UZdE^Q[
*/ oT5xe[{yj
package com.javaeye.common.business; Ss u{Lj
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import java.io.Serializable; j8os6I
import java.util.List; Ar sMqb
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import org.hibernate.Criteria; cLlfncI
import org.hibernate.HibernateException; KrkZv$u,
import org.hibernate.Session; 4[3T%jA
import org.hibernate.criterion.DetachedCriteria; D^PsV
import org.hibernate.criterion.Projections; [&*$!M
import {K'SOhH4?
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org.springframework.orm.hibernate3.HibernateCallback; | 4I x2GD
import
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org.springframework.orm.hibernate3.support.HibernateDaoS .bl0w"c^qq
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upport; ;_i0@@J
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import com.javaeye.common.util.PaginationSupport; x=B+FIJ
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public abstract class AbstractManager extends <nsl`C~6g0
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HibernateDaoSupport { Wsz='@XvB
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privateboolean cacheQueries = false; 8"LaP3U
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privateString queryCacheRegion; %FFw!eVi
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publicvoid setCacheQueries(boolean ~+7yi4(i
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cacheQueries){ |/fbU_d
this.cacheQueries = cacheQueries; [/uKo13
} zFi+6I$
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publicvoid setQueryCacheRegion(String ,P"R.A
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queryCacheRegion){ wI}'wALhA
this.queryCacheRegion = K=5_jE^e
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queryCacheRegion; ap%o\&T;
} ]bnxOk
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publicvoid save(finalObject entity){ z3*G(,
getHibernateTemplate().save(entity); =w A< F
} 0v7;ZxD
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publicvoid persist(finalObject entity){ ]|`gTD6
getHibernateTemplate().save(entity); jPU#{Wo#
} L7Oytdc<
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publicvoid update(finalObject entity){ {t/!a0\HS
getHibernateTemplate().update(entity); <M'IRf/D
} 9_>4~!x`
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publicvoid delete(finalObject entity){ T4!]^_t^
getHibernateTemplate().delete(entity); NuO>zAu
} <uTsXv
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publicObject load(finalClass entity, Ee|+uQ981>
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finalSerializable id){ aY:(0en]&
return getHibernateTemplate().load f,L
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(entity, id); M.8!BB7\8e
} w|nVK9.
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publicObject get(finalClass entity, l.)N
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finalSerializable id){ BWPYHWW}E
return getHibernateTemplate().get NUnP'X=J,
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(entity, id); l wg.'<
} ;W+-x]O
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publicList findAll(finalClass entity){ _5m }g!
return getHibernateTemplate().find("from 8&UuwZ6i-
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" + entity.getName()); \34|9#*z-
} %|,<\~P
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publicList findByNamedQuery(finalString Nz}Q"6L
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namedQuery){ .FXQ,7mZ-
return getHibernateTemplate f.P( {PN
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().findByNamedQuery(namedQuery); ,?d%&3z<a
} 8_,ZJ9l;
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publicList findByNamedQuery(finalString query, iE Oyc59
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finalObject parameter){ rODKM-7+
return getHibernateTemplate PjP%,-@1
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().findByNamedQuery(query, parameter); 0/gcSW
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} 6+u'Tcb
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publicList findByNamedQuery(finalString query, p_AV3
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finalObject[] parameters){ W^N"y&
return getHibernateTemplate +i>q;=~
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().findByNamedQuery(query, parameters); \fz
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} 5VTbW
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publicList find(finalString query){ g7P1]CZ}
return getHibernateTemplate().find |:#mw1
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(query); 9>#|~P&FE
} % KA/
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publicList find(finalString query, finalObject gCJ'wv)6|%
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parameter){ A%PPG+IfA
return getHibernateTemplate().find l17ZNDzLU
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(query, parameter); bevT`D
} }m H>lN
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public PaginationSupport findPageByCriteria SHk[X ]Uo
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(final DetachedCriteria detachedCriteria){ W =zG
return findPageByCriteria g=C<E2'i*
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); +mA=%?l
} 4B]61|A
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public PaginationSupport findPageByCriteria [KH?5C
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(final DetachedCriteria detachedCriteria, finalint S0+zq<
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startIndex){ u,m-6@il
return findPageByCriteria 1955(:I
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(detachedCriteria, PaginationSupport.PAGESIZE, Ln_l>X6j51
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startIndex); %-l:_A
} |&Pl 4P
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public PaginationSupport findPageByCriteria "AouiZkh
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(final DetachedCriteria detachedCriteria, finalint 5 DB>zou
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pageSize, ^eW.hNg
finalint startIndex){ ?X'*
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return(PaginationSupport) 8q3TeMYV
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getHibernateTemplate().execute(new HibernateCallback(){ &%X Jf~IQ
publicObject doInHibernate 3@] a#>
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(Session session)throws HibernateException { pU ]{Z(
Criteria criteria = ? sW`**j
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detachedCriteria.getExecutableCriteria(session); > bF!Y]H
int totalCount = <S$21NtM87
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((Integer) criteria.setProjection(Projections.rowCount ~It+|X=Kx
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()).uniqueResult()).intValue(); ({KAh?
criteria.setProjection dCP Tpm
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(null); 0xUj#)
List items = @izi2ND
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criteria.setFirstResult(startIndex).setMaxResults 4p8jV*:@{
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(pageSize).list(); [\9(@Bx
PaginationSupport ps = LDEt.,6i
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new PaginationSupport(items, totalCount, pageSize, #>jH[Q
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startIndex); gVU\^KN]
return ps; /Q8A"'Nk
} 1K9?a;.
}, true); [|n-x3h
} a<'$` z|s
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public List findAllByCriteria(final W 'a~pB1I
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DetachedCriteria detachedCriteria){ 0Eu$-)
return(List) getHibernateTemplate f_h"gZWV
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().execute(new HibernateCallback(){ ]8>UII ,US
publicObject doInHibernate 37-y
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(Session session)throws HibernateException { N#['fg'
Criteria criteria = ~_db<!a
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detachedCriteria.getExecutableCriteria(session); }r~l72
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return criteria.list(); 'Y{ux>
} wT~;tOw~
}, true); %4|}&,%%r
} ^Pg
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public int getCountByCriteria(final @\`G & VB
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DetachedCriteria detachedCriteria){ R}X_2""
Integer count = (Integer) jjwMvf.R
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getHibernateTemplate().execute(new HibernateCallback(){ >?W;>EUH
publicObject doInHibernate Xb@z7X#O!
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(Session session)throws HibernateException { g~hk-nXL.
Criteria criteria = d<GG(
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detachedCriteria.getExecutableCriteria(session); *DCNu{6
return FR,#s^kF
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criteria.setProjection(Projections.rowCount zg Y*|{4Sl
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()).uniqueResult(); qVD!/;l
} @VC9gdO/
}, true); f93rY<
return count.intValue(); %r
} Be>c)90bO_
} 5f&{ !N
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用户在web层构造查询条件detachedCriteria,和可选的 5@>4)dk\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 J%f=A1Q
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PaginationSupport的实例ps。 a.}:d30
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ps.getItems()得到已分页好的结果集 m wEVEx24
ps.getIndexes()得到分页索引的数组 BRU9LS
ps.getTotalCount()得到总结果数 K~y9zF{
ps.getStartIndex()当前分页索引 Z>Kcz^a#
ps.getNextIndex()下一页索引 .)^3t~
ps.getPreviousIndex()上一页索引 _/%]:
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 dy6F+V\DG
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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 i5E:FS^!I
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一下代码重构了。 g?A5'o&Yu
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我把原本我的做法也提供出来供大家讨论吧: dJQ }{,+6
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首先,为了实现分页查询,我封装了一个Page类: *@G(3 n
java代码: 0'%+X|
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/*Created on 2005-4-14*/ dW{o+9 nw
package org.flyware.util.page; Xs%R]KOwt
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/** # McK46B z
* @author Joa (ju
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* N1+4bR
*/ r>Qyc
publicclass Page { rq'##`H
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/** imply if the page has previous page */ #zSi/r/=1
privateboolean hasPrePage; 9#s95RO
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/** imply if the page has next page */ x<{;1F,k3
privateboolean hasNextPage; &w;^m/zP3
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/** the number of every page */ :_fjml/
privateint everyPage; p;n3`aVh
XC7Ty'#"KX
/** the total page number */ l?@MUsg+
privateint totalPage; "
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/** the number of current page */ y?Hj%,
privateint currentPage; w8ZHk?:
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/** the begin index of the records by the current BYr_Lz|T
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query */ 'XP>} m
privateint beginIndex; +B`'P9Zk@
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/** The default constructor */ KD%xo/Z.
public Page(){ RWh9&O:6'
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} iL7-4Lv#
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/** construct the page by everyPage e8XM=$@
* @param everyPage y(/jTS/hd
* */ Xc8= 2n
public Page(int everyPage){ JK(`6qB>(6
this.everyPage = everyPage; Nh1e1m?
} 0okO+QU,a
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/** The whole constructor */ #uD)0zdw
public Page(boolean hasPrePage, boolean hasNextPage, >+Sv9S
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int everyPage, int totalPage, bxd3
int currentPage, int beginIndex){ #sz]PZ\
this.hasPrePage = hasPrePage; 2A*X Hvwb
this.hasNextPage = hasNextPage; )Y&MIJ7>@
this.everyPage = everyPage; ]^yV`Z8
this.totalPage = totalPage; GZ/pz+)i&
this.currentPage = currentPage; + AcKB82
this.beginIndex = beginIndex; ?o(ZTlT
} Aj8l%'h[
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/** >zPO>.?h7T
* @return
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* Returns the beginIndex. >u9id>+
*/ $'A4RVVT
publicint getBeginIndex(){ iX8h2l
return beginIndex; a'
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} 71k!k&Im
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/** 38V $ <w
* @param beginIndex 4c5^7";P
* The beginIndex to set. avu*>SB
*/ Ij;==f~G
publicvoid setBeginIndex(int beginIndex){ x !#Ma
this.beginIndex = beginIndex; ]k[Q]:q
} 88 Fb1!a5Z
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/** ri/t(m^{W
* @return w8AJ#9W
* Returns the currentPage. wb(*7 &eP:
*/ nuf@}W>y
publicint getCurrentPage(){ (
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return currentPage; V+qFT3?-
} -kG3k> by_
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/** |Hx%f
* @param currentPage =8$|_
* The currentPage to set. m.1LxM$8
*/ 3[MdUj1y[
publicvoid setCurrentPage(int currentPage){ :`:xP
this.currentPage = currentPage; RpHpMtvNo/
} <MPeh&_3#
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/** /HB+ami,
* @return (\Rwf}gyR
* Returns the everyPage. qg^(w fI
*/ @rPI$ia1~
publicint getEveryPage(){ I#i?**
return everyPage; e%PCe9
} mDb-=[W5
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/** kmZ.U>#
* @param everyPage 3x04JE3!
* The everyPage to set. [:AB$l*
*/ 6?53q e
publicvoid setEveryPage(int everyPage){ GLo\q:5A
this.everyPage = everyPage; 0L!er%GM
} 4fu'QZ(}
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/** Wr]O
* @return 4a\n4KO X
* Returns the hasNextPage. xCR;
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*/ ]XmQ]Yit
publicboolean getHasNextPage(){ whV&qe;sw
return hasNextPage; gsW=3m&`
} v*&Uk'4E
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/** hmc\|IF`
* @param hasNextPage 1Z\(:ab13
* The hasNextPage to set. R
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*/ }BA9Ka#%
publicvoid setHasNextPage(boolean hasNextPage){ ]b}B~jD
this.hasNextPage = hasNextPage; CkRyzF
} 5){tBK|
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/** q]F4Lq(
* @return EYA/CI
* Returns the hasPrePage. q!ee g
*/ MzG5u<D
publicboolean getHasPrePage(){ 1v;'d1Hg;
return hasPrePage; $8jaapNm@
} d/l,C4p
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/** u@AI&[Z
* @param hasPrePage \BLp-B1s
* The hasPrePage to set. \s,Iz[0Vfz
*/ ]PeLcB
publicvoid setHasPrePage(boolean hasPrePage){ 0Xp
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this.hasPrePage = hasPrePage; %_>Tcm=
} 1#/6r :
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/** +H41]W6
* @return Returns the totalPage. ,Qat
* I%SuT7"Do
*/ I4rV5;f
H4
publicint getTotalPage(){ ojX%RU
return totalPage; NPS.6qY
} yb69Q#V2
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/** Cy`26[E$S
* @param totalPage F|,6N/;!W
* The totalPage to set. v}Z9+ yRC2
*/ [w,(EE
publicvoid setTotalPage(int totalPage){ +yGY785b
this.totalPage = totalPage; =D{B}=D\IM
} ]y.Rg{iv
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} -RGPtD@
FQ U\0<5
g`kY]lu
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oL#xDG
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 #lofhv
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个PageUtil,负责对Page对象进行构造: Jff 79)f
java代码: Bw6 L;Vu
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2@sr:,\1
/*Created on 2005-4-14*/ 9MT? .q
package org.flyware.util.page; d`85P+Qen|
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import org.apache.commons.logging.Log; k'g$2
import org.apache.commons.logging.LogFactory; p<q].^M
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/**
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* @author Joa 21ViHV
* 7 %3<~'v[
*/ ~> PgJ^G
publicclass PageUtil {
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mGO>""<:
privatestaticfinal Log logger = LogFactory.getLog RE 9nU%!
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[qI
(PageUtil.class); {8 N=WZ
alc]
/** vu<#wW*9
* Use the origin page to create a new page qJ
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* @param page BB63xEx
* @param totalRecords ocwE_dR{
* @return 7lR<@$q
*/ 7-X/>v
publicstatic Page createPage(Page page, int 0vn[a,W<A
}a ^|L"
totalRecords){ 0yz~W(tsm
return createPage(page.getEveryPage(), &+G;R
=-Nsc1&
page.getCurrentPage(), totalRecords); =e{.yggE
} @; ;G88=
q? 9GrwL8F
/** @(>XOj?+
* the basic page utils not including exception g_vm&~U/'
&{ ZSE^
handler 4sIXO
* @param everyPage s/t11;
* @param currentPage ybE[B}pOeZ
* @param totalRecords \2>?6zs
* @return page 3;l "=#5
*/ 4mJFvDZV`
publicstatic Page createPage(int everyPage, int @1bH}QS
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currentPage, int totalRecords){ iP#=:HZu;
everyPage = getEveryPage(everyPage); NAJVr}4f
currentPage = getCurrentPage(currentPage); 2+:'0Krc
int beginIndex = getBeginIndex(everyPage, Kam]Mn'
=|,A%ZGF$
currentPage); PS@ *qTin
int totalPage = getTotalPage(everyPage, ,r`UBQ}?
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totalRecords); 'zxoRc-b@N
boolean hasNextPage = hasNextPage(currentPage, iSiDSeW8
[l*;E
f,
totalPage); kjE*9bUc
boolean hasPrePage = hasPrePage(currentPage); 74f9|~%
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returnnew Page(hasPrePage, hasNextPage, Y(r@v
everyPage, totalPage, d!V$Y}n
currentPage, ?WHy0x20
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beginIndex); QVtM.oi!Q
} i_ QcC
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privatestaticint getEveryPage(int everyPage){ B4Lx{uno
return everyPage == 0 ? 10 : everyPage; 0^&!6R
} Z 0*%Rq
@;Y~frT
privatestaticint getCurrentPage(int currentPage){ Wi$dZOcSJ
return currentPage == 0 ? 1 : currentPage; ~pz FZ7n4
} .=<$S#x^Hb
CS@&^SEj
privatestaticint getBeginIndex(int everyPage, int o@k84+tn(
O3qM1-k}S
currentPage){ 1*UNsEr
return(currentPage - 1) * everyPage; !p[`IWZ
} BsLG^f
CdZ BG
privatestaticint getTotalPage(int everyPage, int F]_cbM{8/
/3B6Mtb
totalRecords){ b$-e\XB!
int totalPage = 0; xs!p|
HOZRYIQB
if(totalRecords % everyPage == 0) fn}UBzED\
totalPage = totalRecords / everyPage; vAi$[p*im
else qp~gP
totalPage = totalRecords / everyPage + 1 ; Y*LaBxt Q
L1#Ij#
return totalPage; 0rE(p2
} 0X9Y~TM%
`xz&Scil
privatestaticboolean hasPrePage(int currentPage){ ]RIVc3?;$
return currentPage == 1 ? false : true; uf' 4'
} [j9E pi(
.}`hCt08
privatestaticboolean hasNextPage(int currentPage, io%')0p5q
tIuoD+AW
int totalPage){ 9uYyfb:
,z
return currentPage == totalPage || totalPage == ycr"Y|
nH[+n `{o
0 ? false : true; !;
v~^#M]~
} %fjuG
I+;-p]~
5VE2@Fn}
} K_/B?h
"!UVs+)]
)TmtSSS
|m
G7XL,
K%j&/T j1
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。 ,,<PVTd
W/+K9S25
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 zO=%J)-=
E]} n(
做法如下: V H^AcO
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Bl;KOR
b=[?b+
的信息,和一个结果集List: my.`k'
java代码: 53OJ-m%a
(ywo
a
1|QvN1?
/*Created on 2005-6-13*/ %_M2N.n
package com.adt.bo; k(s;,B\
8cWZ"v
import java.util.List; _|{aC1Y!V
V5rp.~
import org.flyware.util.page.Page; kBEmmgL
=y]$0nh
/** 8;\sU?
* @author Joa <vc`^Q&4B
*/ F?4(5 K
publicclass Result { )j&"%[2F
x ,/TXTZ6
private Page page; gz#4{iT~
,8Iv9M}2
private List content; 3C>qh{z"
JHV)ZOO
/** &M&{yc*%
* The default constructor A]`:VC=IU
*/ j}HFs0<L
public Result(){
&wH:aD
super(); QOFvsJ<s
} H:&?ha,9
>O`l8tM
/** 0Dv JZ|e
* The constructor using fields !-]C;9Zd
* ~XM[>M\qB
* @param page 8}p8r|d!ls
* @param content <EX7WA
*/ FY0%XW
public Result(Page page, List content){ $r.U
this.page = page; [2Mbk~
this.content = content; 1hQN8!: <
} oW}!vf3z
T`YwJ6N
/** ,32xcj}j)r
* @return Returns the content. f|3q^wjs
*/ ks(SjEF
publicList getContent(){ vn').\,P2O
return content; %n?vJ#aX%
} ?s%v0cF
$< %B#axL
/** V-W'RunnW
* @return Returns the page. L^Wz vv]
*/ &V=7D# L
public Page getPage(){ 6DF
return page; Rs;15@t@
} -e -e9uP
W.}].7}h
/** 9t:]
* @param content BR_TykP
* The content to set. D#rrW?-z
*/ C*~aSl7
public void setContent(List content){ HD`>-E#
this.content = content; eQN.sl5
} JNU/`JN9f
I2Ev~!
/** TR vZ
* @param page cgZaPw2
bw
* The page to set. D@54QJ<
*/ J\co1kO9/
publicvoid setPage(Page page){ n@>wwp
this.page = page; $^% N U
} 0%C^8%(x
} C0C0GqN,
H'g?llh1J
>9K//co"of
fib#CY
*:"^[Ckc
2. 编写业务逻辑接口,并实现它(UserManager, ? 5|/
C
2ypIq
UserManagerImpl) laREjN/\`
java代码: (|h:h(C
jZ9[=?
lu\o`m5wF
/*Created on 2005-7-15*/ Iin#Wd-/
package com.adt.service; b{[*N
4SVW/Zl.?
import net.sf.hibernate.HibernateException; Di(9]:+
:b#%C
pR
import org.flyware.util.page.Page; i.a _C'<$
7nE"F!d+0
import com.adt.bo.Result; F1W+o?B
)c<6Sfp^B
/** aq>?vti1D
* @author Joa M@7Xp)S"
*/ {[#(w75R{
publicinterface UserManager { 8n)WW$
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public Result listUser(Page page)throws CY"i-e"q<Q
/'&;Q7!)
HibernateException; pO/%N94s
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} nfE@R."A
)iE"Tl
2<W&\D o@
T_hV%
!C&%T]
java代码: Z5)eREi=
]|oJ)5P
.[pUuVq]
/*Created on 2005-7-15*/ ! q6hC
package com.adt.service.impl; `lCuU~~ag
I0w%8bs
import java.util.List; Gp2!xKgm
lgD]{\O$ip
import net.sf.hibernate.HibernateException; 8I#D`yVKc
+<(a}6dt
import org.flyware.util.page.Page; &^QPkX@p
import org.flyware.util.page.PageUtil; AlX3Wv}
:=!Mh}i
import com.adt.bo.Result; DdjCn`jqlf
import com.adt.dao.UserDAO; 2<6j1D^jM
import com.adt.exception.ObjectNotFoundException; Z7#7N wy4
import com.adt.service.UserManager; Os&1..$Nb
H!eh
J$[
/** -Zy)5NB-tZ
* @author Joa o:\XRPB
*/ x-Z^Q C
publicclass UserManagerImpl implements UserManager { 9D_wG\g
`iYc<N`
private UserDAO userDAO; rw u3Nb
zy)i1d
/** ~
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* @param userDAO The userDAO to set. 7'j9rmTXs
*/ IC~ljy]y_
publicvoid setUserDAO(UserDAO userDAO){ O%$O(l
this.userDAO = userDAO; Q"}s>]k3_
} \qq-smcM-
z,Xk\@
/* (non-Javadoc) 5si}i'in
* @see com.adt.service.UserManager#listUser 7'.s7&
'7
%C*^:\y
(org.flyware.util.page.Page) gGbI3^r#
*/ ;'1Apy
public Result listUser(Page page)throws ,U=E[X=H
*x,HnHT
HibernateException, ObjectNotFoundException { >>V&yJ_
int totalRecords = userDAO.getUserCount(); > V%Q O>C
if(totalRecords == 0) h6QWH
throw new ObjectNotFoundException Vyt
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]P3[.$z
("userNotExist"); P\(30
page = PageUtil.createPage(page, totalRecords); LknVqZ|k
List users = userDAO.getUserByPage(page); -Bv12ymLG
returnnew Result(page, users); bXvbddu)}
} ,}7_[b)&V
CA^.?&CH^O
} %$9:e
J?
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chLeq
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f/>
n~%}Z[5D
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 w2Kq(^?
lU$X4JBzS
询,接下来编写UserDAO的代码: ^x3EotQ\
3. UserDAO 和 UserDAOImpl: z93nYY$`Y
java代码: ;&mxqY8`'
6ZgNHARS
p#<nK+6.8
/*Created on 2005-7-15*/ Q\WXi
package com.adt.dao; VM;g+RRq
e6m1NH4,
import java.util.List; f\'G`4e
`.8-cz
import org.flyware.util.page.Page; PP4d?+;V
5"2@NL
import net.sf.hibernate.HibernateException; $jcz?vH
k~|ZO/X@l%
/** cG(0q[
* @author Joa |_I[1%&`N
*/ |Gc&1*$
publicinterface UserDAO extends BaseDAO { 9:\A7 =
DpNX66O
publicList getUserByName(String name)throws O3xz|&xY&
m)k-uWc$C
HibernateException; I}%mfojC
}K;iJ~kD1
publicint getUserCount()throws HibernateException; -x?Hj/
D(@SnI+
publicList getUserByPage(Page page)throws \E&th p
Zh? V,39
HibernateException; .h6Y<
E
k(9s+0qe
} [oJ& J>U'
JU2P%3
VO|u8Z"
P2QRvn6v
ir+8:./6
java代码: "i(U
_Q^y_f
W
U0UG$o`
/*Created on 2005-7-15*/ 0#]!#1utg
package com.adt.dao.impl; 0STk)>3$-
SZE `J:w
import java.util.List; oVreP
e
sGlMq
import org.flyware.util.page.Page; oFn4%S:
~D_rZ&
import net.sf.hibernate.HibernateException; :SdIU36
import net.sf.hibernate.Query; C#T)@UxBZ
.W-=x,`hY4
import com.adt.dao.UserDAO; pKYLAt+^>
BArJ"t*/z
/** wRj~Qv~E
* @author Joa *Ji9%IA
*/ Sy:K:Z|[U
public class UserDAOImpl extends BaseDAOHibernateImpl u{pTva
YpiRF+G
implements UserDAO { "d:.*2Z2
7s!AHyZ
/* (non-Javadoc) ec#_olG%
* @see com.adt.dao.UserDAO#getUserByName c%b\CP\)W
du8!3I
(java.lang.String) k|fh\F+$
*/ Q>V?w gZ
publicList getUserByName(String name)throws VAt>ji7c
TftOYY.hQ
HibernateException { ko>M&/^
String querySentence = "FROM user in class pj j}K
O/nqNQ?<
com.adt.po.User WHERE user.name=:name"; |<'10
Query query = getSession().createQuery C~:b* X
7Z
VVR*n|
(querySentence); 4fD`M(wv
query.setParameter("name", name); XCV0.u|
return query.list(); z3ZuC{
} L2k;f]
. ^BWR
/* (non-Javadoc) Y0rf9
* @see com.adt.dao.UserDAO#getUserCount() fo*!a$)
*/ LuLy6]6D;
publicint getUserCount()throws HibernateException { Fz{o-4
int count = 0; 2"zI R(
String querySentence = "SELECT count(*) FROM 0NVG"-Q
x}uwWfe 3
user in class com.adt.po.User"; E=A/4p6\$
Query query = getSession().createQuery (tTLK0V-|3
e1oFnu2R
(querySentence); )!BB/'DRQ
count = ((Integer)query.iterate().next KqFmFcf|
_AVy:~/
()).intValue(); +V6j`
return count; rnJS[o0
} Qz'O{f
J&(
/* (non-Javadoc) EWSr@}2j
.
* @see com.adt.dao.UserDAO#getUserByPage ws#hhW3qK
l
DgzM3
(org.flyware.util.page.Page) KX]-ll
*/ zj%cd;
publicList getUserByPage(Page page)throws 9]"\"ka3>
bx1G
CD
HibernateException { }`#j;H$i
String querySentence = "FROM user in class zf}rfn
u|(aS^H=q
com.adt.po.User"; (69kvA&|q
Query query = getSession().createQuery HW^{ ;'kH~
(2n3exx
(querySentence); >3v0yh_3
query.setFirstResult(page.getBeginIndex()) w($XEv;
.setMaxResults(page.getEveryPage()); KwY`<t1lA;
return query.list(); #d3[uF]OmW
} AX/=}G
&mCs%l
} *{HGLl|=
*sIi$1vHu
hg(KNvl
c>M_?::)0
C,V|TF.i2
至此,一个完整的分页程序完成。前台的只需要调用 Kv(Y }
3xc:Y>
*`
userManager.listUser(page)即可得到一个Page对象和结果集对象 0^-z?Kb<}
mm3zQ!2j.
的综合体,而传入的参数page对象则可以由前台传入,如果用 =9#i<te
T]5U_AI@
webwork,甚至可以直接在配置文件中指定。 O<gP)ZW~
E>o&GYc
下面给出一个webwork调用示例: # Lu4OSM+
java代码: 8Ng))7g!
1t!&xvhG
|j\eBCnH3
/*Created on 2005-6-17*/ OFJJ-4[_3
package com.adt.action.user; c }g$1of87
\mqhugy
import java.util.List; rjq -ZrC%
w; yar=n
import org.apache.commons.logging.Log; :/n
?4K^
import org.apache.commons.logging.LogFactory; 0tn7Rkiw
import org.flyware.util.page.Page; A0'tCq]?0
cuJ/ Vc
import com.adt.bo.Result; ,:\zXESy4
import com.adt.service.UserService; RXIH(WiK
import com.opensymphony.xwork.Action; 5|{ t+u
}s8*QfK>
/** H{p[Ghp
* @author Joa +z{x 7
*/ ',v0vyO8
publicclass ListUser implementsAction{ 3/]f4D{MMY
-K{\S2
privatestaticfinal Log logger = LogFactory.getLog #$9U=^Z[
;tZ}i4Ud
(ListUser.class); C={sE*&dYX
q{N lF$X
private UserService userService; f)!{y>Q
uhPIV\
private Page page; l%v hV&
>B|ofwm*
privateList users; ulJ+:zwq$
zwF7DnW<<
/* ZVCv(J
* (non-Javadoc) JC1BUheeb
* ?Vb=4B{~
* @see com.opensymphony.xwork.Action#execute() ^ ^U)WB
*/ D(W7O>5vQ2
publicString execute()throwsException{ t/4/G']W
Result result = userService.listUser(page); )[a?J,
page = result.getPage(); M$E8:
users = result.getContent(); *;~{_Disz
return SUCCESS; [xH2n\7
} yDl5t-0`
4.$hHFqS^5
/** |G5=>W
* @return Returns the page. iyHp$~,q?t
*/ Av\0GqF
public Page getPage(){ HvL9;^!
return page; *>R/(Q
} l-JKcsM
6r?cpJV{
/** 6'X.[0M
* @return Returns the users. *AJezhR
*/ !7#froh
publicList getUsers(){ ,&
{5,=
return users; `OF g.R|
} pRa oR
s2
t-T0;
/** Y?q*hS0!H
* @param page 2T{-J!k
* The page to set. wN%DM)*k
*/ Z2Y583D
publicvoid setPage(Page page){ w Lg:YM"
this.page = page; c"_H%x<[
} %[31ZFYB
E,nYtn|B
/** d%"@#bB
* @param users {yl/T:Bh&
* The users to set. `~s,W.Eu4
*/ =Am*$wGI
publicvoid setUsers(List users){ D6@4
this.users = users; 7{6cLYl
} `dq3=
b&_u
O
/** ps4Wwk(
* @param userService Toa#>Z*+Rb
* The userService to set. e&VR>VJEA
*/ I'wk/
publicvoid setUserService(UserService userService){ q2"'W|I
this.userService = userService; y*TNJJ|
} 3C5D~9v
} hghto
\G5Y
Y+5A2Z)f[
kA9 X!)2w
I@3c QxI
[Z`:1_^0}
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, `E1_S
oew]ijnB
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 R<