Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 l8
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Y_iF$m/R
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 6"c!tJc7j
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 wP *a>a
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。 !z6/.>QJ~
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分页支持类: [q|Q]O0
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java代码: VDI S`E
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package com.javaeye.common.util; P`Wf'C^h
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import java.util.List; U~`^Y8UF
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publicclass PaginationSupport { (DaP~*c3cC
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publicfinalstaticint PAGESIZE = 30; eOnl
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privateint pageSize = PAGESIZE; sn-+F%[
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privateList items; f#-T%jqnK
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privateint totalCount; 9'L0Al~L
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privateint[] indexes = newint[0]; f$*9J
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privateint startIndex = 0; M/`z;a=EP
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public PaginationSupport(List items, int ,OFr]74\
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totalCount){ K OHH74}_
setPageSize(PAGESIZE); s 17gi,"X
setTotalCount(totalCount);
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setItems(items); Dve5m=
setStartIndex(0); I6Q_A
} 745V!#3!M
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public PaginationSupport(List items, int c15^<6]g
^)]*10
totalCount, int startIndex){ ${:$jX[
setPageSize(PAGESIZE); 9 7qS.Z27
setTotalCount(totalCount); SPm5tU
setItems(items); s~ZC!- [;
setStartIndex(startIndex); r*xw\
} ?4||L8j2^
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public PaginationSupport(List items, int bM_(`]&*
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totalCount, int pageSize, int startIndex){ ">^]^wa08
setPageSize(pageSize); >~8Df61o`
setTotalCount(totalCount); 2gI_*fG1
setItems(items); C+IE<=%F
setStartIndex(startIndex); cr;`0
} j`pR;XL1[
i*E`<9
publicList getItems(){ ee?ZkU#@
return items; P`v~L;f
} -L<Pm(v&
8WQ%rN={8
publicvoid setItems(List items){ SJr:
this.items = items; 90v18k
} IYC#H}
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publicint getPageSize(){ j %0_!*#3
return pageSize; h\ek2K
} ,H1~_|)<
31 ;T$5 v1
publicvoid setPageSize(int pageSize){ 1! [bu
this.pageSize = pageSize; Q]:%Jj2
} [|Pe'?zkf
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publicint getTotalCount(){ b:&$x (|
return totalCount; V1U[p3J-S
} p&27|1pZm
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publicvoid setTotalCount(int totalCount){ ZKL%rp_
if(totalCount > 0){ NUtyUv
this.totalCount = totalCount; ~n
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int count = totalCount / \+A<s,x
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pageSize; 1/BMs0 =
if(totalCount % pageSize > 0) / kGX 6hh
count++; UL"3skV
indexes = newint[count]; ]997`,1b
for(int i = 0; i < count; i++){ z1 px^#
indexes = pageSize * m?`Rl6!@8\
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i; *G=AhH$t
} c'qM$KN9G
}else{ L`
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this.totalCount = 0; B.WkHY%/
} b(Xg6
} iROM?/$
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publicint[] getIndexes(){ !r
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return indexes; ?8m/]P/~
} 6p{x2>2y[
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publicvoid setIndexes(int[] indexes){ N^N?!I
this.indexes = indexes; m~B=C>r}t
} DNe^_v)]|
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publicint getStartIndex(){ { "c,P:S]
return startIndex; Q7%#3ML
} 8hp]+k_y
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publicvoid setStartIndex(int startIndex){ L?(rv.lb
if(totalCount <= 0) l[| e3<H
this.startIndex = 0; mjHY-lK
elseif(startIndex >= totalCount) qm8RRDG
this.startIndex = indexes SLo/7$rct
YR.'JF`C
[indexes.length - 1]; #"JU39e
elseif(startIndex < 0) R<Tzt'z
this.startIndex = 0; bb/MnhB
else{ A'EA !
this.startIndex = indexes xGA0]
_
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[startIndex / pageSize]; {`Z)'G\`
} NBYE#Uih
} ^IYN"yX_
t_Wn<)XA
publicint getNextIndex(){ o3kj7U:'x
int nextIndex = getStartIndex() + 20)Il:x
#!Fs[A5%
pageSize; 7:%K-LeaQu
if(nextIndex >= totalCount) A-$BB=Ot
return getStartIndex(); i=+6R
else 0=DawJ9
return nextIndex; <H/H@xQ8G
} 5?MvO]_
t |h mEHUk
publicint getPreviousIndex(){ bwFc>{Wo5
int previousIndex = getStartIndex() - |VL,\&7rk
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pageSize; Vba}RF[b
if(previousIndex < 0) rl=_ "sd=
return0; @~ L.m}GF
else HfiM]^
return previousIndex; |O?Aj1g[c?
} ) b8*>k
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} 3!L)7Z/
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抽象业务类 5KSsRq/8"
java代码: IuF-bxA
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/** 0a'y\f:6*
* Created on 2005-7-12 BKEB,K=K@
*/ 5EUkp6Y
package com.javaeye.common.business; 0*/~9n-Vl
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import java.io.Serializable; `39U I7
import java.util.List; O.dNhd$
*79<ypKG$
import org.hibernate.Criteria; `h'^S,'*
import org.hibernate.HibernateException; :O%O``xT
import org.hibernate.Session; 8Bvjj|~ (@
import org.hibernate.criterion.DetachedCriteria; 10&A3C(E
import org.hibernate.criterion.Projections; m.*+0NG
import ceCshxTU
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org.springframework.orm.hibernate3.HibernateCallback; .YkKIei
import 5\J;EWTU
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org.springframework.orm.hibernate3.support.HibernateDaoS voxlo>:
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upport; g:g>;"B
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import com.javaeye.common.util.PaginationSupport; "<WSEs
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public abstract class AbstractManager extends :jPAA`,
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HibernateDaoSupport { r.GjM#X
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privateboolean cacheQueries = false; lI 8"o>-~
mx yT==E
privateString queryCacheRegion; U PC& O
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publicvoid setCacheQueries(boolean &g`a [#
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cacheQueries){ 0)NHjKP
this.cacheQueries = cacheQueries; fomkwN
} v\c3=DbO
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publicvoid setQueryCacheRegion(String `dK\VK^
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queryCacheRegion){ WA/\x
this.queryCacheRegion = BhjXNf9[
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queryCacheRegion; ]Vsze4>Z[
} c2nZd.SD|
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publicvoid save(finalObject entity){ ZS-9|EA<
getHibernateTemplate().save(entity); QEPmuG
} C*9m `xh
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publicvoid persist(finalObject entity){ saV `-#
getHibernateTemplate().save(entity); /dqKFxB1
} #E1*1E
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publicvoid update(finalObject entity){ $
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getHibernateTemplate().update(entity);
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} [D)A+
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publicvoid delete(finalObject entity){ ICi- iX
getHibernateTemplate().delete(entity);
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} xOT3>$
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publicObject load(finalClass entity, JnZxP> 2B
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finalSerializable id){ dw-r}Qioe
return getHibernateTemplate().load .UcS4JU
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(entity, id); ^\!p;R
} e:l 6;
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publicObject get(finalClass entity, ~(8A&!#,!
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finalSerializable id){ s|%</fMt9
return getHibernateTemplate().get !EFd-fk
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(entity, id); "hvw2lyp3
} ZFzOW
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publicList findAll(finalClass entity){ /vMpSN|3
return getHibernateTemplate().find("from b?$3jOtW
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" + entity.getName()); ~AO0(Lp
} |] YT6-?.
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publicList findByNamedQuery(finalString $Z j.
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namedQuery){ A1C@'9R*
return getHibernateTemplate &jJgAZ!
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().findByNamedQuery(namedQuery); Ov9.qNT
} NF.SGga
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publicList findByNamedQuery(finalString query, `/U:u9H9v
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finalObject parameter){ 4MIVlg9
return getHibernateTemplate x83XJFPWL
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().findByNamedQuery(query, parameter); 5&>(|Y~I
} 0jXIx2y
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publicList findByNamedQuery(finalString query, 6f?DW-)jp/
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finalObject[] parameters){ T \A uL
return getHibernateTemplate arB$&s
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().findByNamedQuery(query, parameters); K5KN}sRs"
} , ^nUi c
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publicList find(finalString query){ p)oW'#@a
return getHibernateTemplate().find BYY>;>V
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(query); =4[zt^WX"
} O []+v
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publicList find(finalString query, finalObject 1$|z%(
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parameter){ n33SWE(
return getHibernateTemplate().find 'G^=>=w|Nv
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(query, parameter); \yxr@z1_b
} lG{J
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public PaginationSupport findPageByCriteria UJZa1p@L
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(final DetachedCriteria detachedCriteria){ pM=vW{"I/
return findPageByCriteria 2::T, Z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); gR6:J
} LDNpEX~
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public PaginationSupport findPageByCriteria Qknd ^%
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(final DetachedCriteria detachedCriteria, finalint aql*@8
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startIndex){ &Ls0!dWC
return findPageByCriteria 2P|-V} ;9
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(detachedCriteria, PaginationSupport.PAGESIZE, s:_5p`w>
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startIndex); x:2_FoQ
} BgRiJFa.d[
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public PaginationSupport findPageByCriteria +vuW9
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(final DetachedCriteria detachedCriteria, finalint wEp/bR1=
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pageSize, N\0Sq-.
finalint startIndex){ OS,$}I[`8
return(PaginationSupport) jzV#%O{`
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getHibernateTemplate().execute(new HibernateCallback(){ "Vh(%N`6
publicObject doInHibernate 9qPP{K,Pq2
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(Session session)throws HibernateException { Y~C S2%j
Criteria criteria = EKt-C_)U
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detachedCriteria.getExecutableCriteria(session); =SdWU}xn2
int totalCount = XyI w5
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((Integer) criteria.setProjection(Projections.rowCount *qqFIp^
@s/ qOq?
()).uniqueResult()).intValue(); h"'f~KM9a>
criteria.setProjection s.~SV"
4>|5B:
(null); 4[#.N
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List items = `+gF|o9
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criteria.setFirstResult(startIndex).setMaxResults GZ e
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(pageSize).list(); *Dn{MD7,M
PaginationSupport ps = 0uvL,hF
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new PaginationSupport(items, totalCount, pageSize, jlB3BwG{w
Ns $PS\
startIndex); LY>JE6zTt
return ps; /t/q$X
} E,X,RM~
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}, true); p-}:7CXP
} qkEy$[D9
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public List findAllByCriteria(final q8D1MEBL`
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DetachedCriteria detachedCriteria){ @!S$gTz
return(List) getHibernateTemplate qvscf_%FM
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().execute(new HibernateCallback(){ U".-C`4v
publicObject doInHibernate c;e,)$)-|
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(Session session)throws HibernateException { w"e2}iE7
Criteria criteria = Xnh1pwDhe<
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detachedCriteria.getExecutableCriteria(session); Z`%;bP:
return criteria.list(); e`oc#Od&x]
} KV6S-
}, true); `7j,njCX.
} LiRY-;8=
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public int getCountByCriteria(final MnQ_]cC
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DetachedCriteria detachedCriteria){ oHYD6qJX{
Integer count = (Integer) s6egd%r
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getHibernateTemplate().execute(new HibernateCallback(){ {\e}43^9N
publicObject doInHibernate }8SHw|-
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(Session session)throws HibernateException { V OX>Sl
Criteria criteria = PTP2QAt
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detachedCriteria.getExecutableCriteria(session); XVfQscZe
return Hke\W'&
7[)(;-
criteria.setProjection(Projections.rowCount ?/wloLS47
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()).uniqueResult(); f[RnL#*xJU
} Xx^c?6YM
}, true); jDnh/k0{d
return count.intValue(); kel {9b=i
} AM[:Og S
} *"
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)/
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用户在web层构造查询条件detachedCriteria,和可选的 2S;zze7)
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *v9G#[gG
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PaginationSupport的实例ps。 :-Pj )Y{I
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ps.getItems()得到已分页好的结果集 7Tbk ti;
ps.getIndexes()得到分页索引的数组 F)@<ZE
ps.getTotalCount()得到总结果数 B_S3}g<~
ps.getStartIndex()当前分页索引 bo2Od
ps.getNextIndex()下一页索引 !8g
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ps.getPreviousIndex()上一页索引 *.RVH<W=8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 k-U/x"Pl
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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 ;vitg"Zh>
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一下代码重构了。 93\,m+-
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我把原本我的做法也提供出来供大家讨论吧: 4pqZ!@45|
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首先,为了实现分页查询,我封装了一个Page类: BP6Shc|C
java代码: wOOPWwk
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/*Created on 2005-4-14*/ =m:W
package org.flyware.util.page; 7r>W r#
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/** NS q=_8
* @author Joa 5glGlD6R
* 0YL0Oa+7
*/ =Ug_1w
publicclass Page { N,|oV|i
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/** imply if the page has previous page */ Fn,|J[sC
privateboolean hasPrePage; GLyh1qNX
]_?y[@ZP
/** imply if the page has next page */ >y[S?M
privateboolean hasNextPage; jq)|Uq'6
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/** the number of every page */ '_)tR;s
privateint everyPage; c &HoS
qE}YVKV*
/** the total page number */ L nGSYrx1
privateint totalPage; /`> P|J
$}$@)!-
/** the number of current page */ _u$K Lqt/,
privateint currentPage; ]Ho`*$dD
}3 }=tN5
/** the begin index of the records by the current ([~`{,sv
c29Z1Zs2)
query */ 1tdCzbEn+
privateint beginIndex; 27:x5g?
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$ *A3p
/** The default constructor */ >gJWp@6V
public Page(){ qgNK!(kWpr
3;:V1_JA
} ^q\zC%.
LS'=>s"
/** construct the page by everyPage s`RJl V
* @param everyPage '9@R=#nd
* */ "[yiNJ"kt
public Page(int everyPage){ vuBA&j0C
this.everyPage = everyPage; *\", qMp
} #cS,5(BM
@XC97kGWp
/** The whole constructor */ |T *qAJ8c
public Page(boolean hasPrePage, boolean hasNextPage, R:N-y."La.
+ctv]'P_
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int everyPage, int totalPage, LnS>3$t*
int currentPage, int beginIndex){ MFuI&u!g:
this.hasPrePage = hasPrePage; c ?XUb[
this.hasNextPage = hasNextPage; .Er/t"Qs;
this.everyPage = everyPage; Z"X*FzFo
this.totalPage = totalPage; 8
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this.currentPage = currentPage; VsEAo
this.beginIndex = beginIndex; u(702S4
} gH3kX<e
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/** Z;D3lbqE
* @return S8m&Rj3O&
* Returns the beginIndex. PDng!IQ^
*/ D5u"4\g<&
publicint getBeginIndex(){ #Ca's'j&f
return beginIndex; Q%Q?q)x
} 3:lp"C51
nX%'o`f
/** 0!`7kZrN
* @param beginIndex ]bb}[#AY
* The beginIndex to set. C}_:K)5q
*/ Y{RB\}f(
publicvoid setBeginIndex(int beginIndex){ ~79Qg{+]N
this.beginIndex = beginIndex; Tj5@OcA$
} J5_Y\@
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/** yX3H&F6
* @return 3z92Gy5cr
* Returns the currentPage. 8p{
*/ Gcz@ze
publicint getCurrentPage(){ gecT*^
return currentPage; -Jo :+].
} Cnci%eo
t<,p-TM]
/** g4a X
* @param currentPage ?0<INS~
* The currentPage to set. FNCLGAiZ
*/ UQ])QTrZFi
publicvoid setCurrentPage(int currentPage){ AO$PuzlLh
this.currentPage = currentPage; Juqn
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} e.|RC
hRIS[#z;U
/** vx}Z
* @return Ej09RO"pB
* Returns the everyPage. 5|G3t`$pa
*/ #aY<J:Nx
publicint getEveryPage(){ 1[g!^5W
return everyPage; y6jmn1K
} gzCMJ<3!D
I S8nvx\
/** u;ooDIq@
* @param everyPage F%Umau*1
* The everyPage to set. =z1o}ga=EA
*/ m$mY<Q
publicvoid setEveryPage(int everyPage){ k5QD5/Ej
this.everyPage = everyPage; m:fouMS
} 124L3AG
ivz9R'
/** {-N90Oe
* @return <` j[;>O
* Returns the hasNextPage. 2vdQ&H4
*/ *a,.E6C*
publicboolean getHasNextPage(){ |4> r"
return hasNextPage; 7h9[-d6
} 4O_+4yS
3r:)\E+Q_
/** fw v
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* @param hasNextPage <&s)k
* The hasNextPage to set. w[7.@ %^[
*/ J*~2:{=%
publicvoid setHasNextPage(boolean hasNextPage){ gq_7_Y/
this.hasNextPage = hasNextPage; j /dE6d
}
p $1Rgm\
PT@e),{~o9
/** ph12x: @B
* @return ]n]uN~)9
* Returns the hasPrePage. 7M#$: Fdb
*/ JRjMt-7H_
publicboolean getHasPrePage(){ C:GHP$/}
return hasPrePage; wQ=yY$VP
} ]RXtC*
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/**
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* @param hasPrePage M|5]#2J_2
* The hasPrePage to set. JlDDM
%
*/ 5 (21gW9
publicvoid setHasPrePage(boolean hasPrePage){ 4 ^~zN"6]
this.hasPrePage = hasPrePage; r>:L$_]L
} *- IlF]
#"p1Qea$
/** 5Jhbf2-
* @return Returns the totalPage. ?+,*YVT
* r5!x,{E6
*/ ^o6)[_L
publicint getTotalPage(){ SXo[[ao
return totalPage; OT}Yr9h4
} kV:FJx0xP
;Ma/b= Y
/** 8LQ59K_WX
* @param totalPage ?F87C[o
* The totalPage to set. Y =g>r]2
*/ $dZ>bXUw:
publicvoid setTotalPage(int totalPage){ &. =}g]
this.totalPage = totalPage; Z"n'/S:q
} "gbnLKs
q?Ku}eID3
} UC+7-y,
le^_6|ek
> 0Twr
BsK|:MM]
aFr!PQp4{
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 vpeBQ=2\
8>VI$
个PageUtil,负责对Page对象进行构造: przubMt
java代码: I`"-$99|t1
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/*Created on 2005-4-14*/ z>mZT.
package org.flyware.util.page; >FY&-4+v
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import org.apache.commons.logging.Log; 8yE%X!E
import org.apache.commons.logging.LogFactory; iFnOl*TC
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/** ~~xyFT+{F
* @author Joa 4C,kA+P
* a81!~1A
*/ $(KIB82&
publicclass PageUtil { ovQS
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privatestaticfinal Log logger = LogFactory.getLog !v-w6WG"
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(PageUtil.class); Z{a{H X[Jx
1!>bhH}{D
/** 462!;/y
* Use the origin page to create a new page @)OnIQN~
* @param page )BF \!sTn
* @param totalRecords '0R/6Z|/Y
* @return y$j1?7
*/ :cXIO
publicstatic Page createPage(Page page, int ZRXI?Jr%
){O1&|z-
totalRecords){ u}-d7-=
return createPage(page.getEveryPage(), uQ:ut(
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page.getCurrentPage(), totalRecords); Wj&<"Z6'm(
} %;pD8WgJA
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/** 'GV&]
* the basic page utils not including exception mD D4_E2*
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handler (j8GiJ]{L,
* @param everyPage
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* @param currentPage 6?%]odI#
* @param totalRecords lq>*x=<
* @return page \3t,|%v
*/ QO5OnYh
publicstatic Page createPage(int everyPage, int 'v'`
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currentPage, int totalRecords){ (oLpnjJ(,
everyPage = getEveryPage(everyPage); %'{V%IXQ
currentPage = getCurrentPage(currentPage); "t5
+*
int beginIndex = getBeginIndex(everyPage, _, \y2&KT
-]Q3/"Q
currentPage); &q4ox7 1
int totalPage = getTotalPage(everyPage, "[awmZ:wo
'fS?xDs-v
totalRecords); JZ %`%rA
boolean hasNextPage = hasNextPage(currentPage, W.yV/fu
vx04h ~
totalPage); k k
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boolean hasPrePage = hasPrePage(currentPage); t*o7,
r> Fec
returnnew Page(hasPrePage, hasNextPage, o{9?:*?7
everyPage, totalPage, qAUaF;{
currentPage, ge^!F>whr
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beginIndex); D",A$(lG
} *w=z~Jq^R"
/t$rX3A
privatestaticint getEveryPage(int everyPage){ (3AYy0J%
return everyPage == 0 ? 10 : everyPage; rQ=xcn[A
} &|/vM.
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privatestaticint getCurrentPage(int currentPage){ ])N|[ |$
return currentPage == 0 ? 1 : currentPage; sk#9x`Rw
} jz
%;4e~t
H!Wis3S3G
privatestaticint getBeginIndex(int everyPage, int nA>*IU[
j'k8^*M6
currentPage){ L5R `w&Up
return(currentPage - 1) * everyPage; f8^"E $"
} i B%XBR
dj3|f{kg{
privatestaticint getTotalPage(int everyPage, int &K06}[J
+*n]tlk
totalRecords){ b+W)2rFO
int totalPage = 0; ah 4kA LO
*]FgfttES
if(totalRecords % everyPage == 0) zs4>/9O
totalPage = totalRecords / everyPage; P`}$-#D F
else u06tDJ[
totalPage = totalRecords / everyPage + 1 ; xy2\'kS`G
{V.Wk
return totalPage; Z/xV\Ggx
} /CIx$G
SrSG{/{
privatestaticboolean hasPrePage(int currentPage){ 7Aqn[1{_O
return currentPage == 1 ? false : true; ,r@xPZPz:e
} NI^{$QMj
"PMO
privatestaticboolean hasNextPage(int currentPage, '-`O.
4u
|drf"lX<{
int totalPage){ Pl_^nFm0
return currentPage == totalPage || totalPage == yU *u
&xgZFSq
0 ? false : true; F@g17 aa
} [C~fBf5
hl`u"?rg
Xc{ZN1 4n
} Og+)J9#
bdCykG-
x,w8r+~5
yXkt:O,i
c2/"KT
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。 j]AekI4I
?'Cb-C_
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 hMv2"V-X
8IeI0f"l)
做法如下: '[%jjUU
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?qy*s3j'M
[@ILc*2O
的信息,和一个结果集List: ebzzzmwo
java代码: 1y7y0V
Qy/uB$q{A
FzVZs#O
/*Created on 2005-6-13*/ lBS"3s384
package com.adt.bo; g#w`J\iz
s}s|~
import java.util.List; tbg*_ZQO u
3eWJt\}?B
import org.flyware.util.page.Page; 2H6:np|O
\/n+j!
/** VXA[TIqp
* @author Joa f#1/}Hq/I
*/ Cc2MYm8
publicclass Result { b(/j\NWC
[M`=HhJ4
private Page page; d<!IGt4Ky
sp^Wo7&g
private List content; UAdz-)$
|4Qx=x>
/** <Kg2$lu(_`
* The default constructor ><cU7 ja[^
*/ hzv3F9.x
public Result(){ v_.HGGS
super(); 0JK2%%
} +N7"EROc
w\Iqzpikr
/** vf[&7n
* The constructor using fields \Y+")
* w=|py>%
* @param page RJ@\W=aZ
* @param content JwB"\&'1ZS
*/ cu)U7
public Result(Page page, List content){ fa4=h;>a+
this.page = page; G?R_aPP
this.content = content; 7_KXD#
} *U_S1>0n
~}K{e
/** 5?w.rcN[j
* @return Returns the content. RtwUb(wn6
*/ |U EC
publicList getContent(){ "-P/jk
return content; f}2;N
} 3-iD.IAUm@
IytDvz*|
/** sCkO0dl8
* @return Returns the page. (vnoP< 0
*/ @7%.7LK
public Page getPage(){ i-]U+m*
return page; \ADLMj`F|
} L:pUvcAc?
$~G@
/** ;
h85=l<8u
* @param content tvGlp)?.
* The content to set. []gRfM]$&
*/ 2QL?]Vo
public void setContent(List content){ \sITwPA[z
this.content = content; dZDK7UL
} Z%OW5]q
b)`pZiQP
/** >Mw'eQ0(y
* @param page ws[/
* The page to set. 7E\g
&R.
*/ T)~!mifX
publicvoid setPage(Page page){ -=a[J;'q
this.page = page; #|?8~c;RWG
} (0R2T"/
} Im+7<3Z
e1UITjy
f3vF"O
BPewc9RxV
^KbL
,T
2. 编写业务逻辑接口,并实现它(UserManager, v%nP*i9
!D;c,{Oz
UserManagerImpl) ?A&%Cwj
java代码: G|*G9nQ
7&foEJ3q
xNIGO/uI~
/*Created on 2005-7-15*/ + {e`]t>_
package com.adt.service; K{2h9 ]VF
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A(:"
import net.sf.hibernate.HibernateException; , D"]y~~I5
(:n|v%
import org.flyware.util.page.Page; (v^Z BM_
"mA1H]r3
import com.adt.bo.Result; qnXTNs
?b
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/** d@ (vg
* @author Joa AG>\aV"b
*/ o0mJy'
publicinterface UserManager { yLqF ,pvO
?oKL&I@
public Result listUser(Page page)throws R5kH0{zM
n"Z |e tZ4
HibernateException; Y{+3}drJE
*)D1!R<\,R
} :j,}{)5=
$DE&J4K
CmHyAw(
`{o$F ::(
RG}}Oh="v
java代码: ``4?a7!!
4.w"(v9 V
V;;#/$oU:4
/*Created on 2005-7-15*/ N}mh}
package com.adt.service.impl; ~},W8\C>
]\dHU.i
import java.util.List; t^U^Tr
AY88h$a
import net.sf.hibernate.HibernateException; 2y%R:Mu
BIj
import org.flyware.util.page.Page; c\K<sM{
import org.flyware.util.page.PageUtil; 12OlrU
30d#Lq
import com.adt.bo.Result; Mk5RHDh
import com.adt.dao.UserDAO; iRt*A6`m+
import com.adt.exception.ObjectNotFoundException; vaB!R 0
import com.adt.service.UserManager; {SdO9Yy?@7
b# ='^W3
/** EO:avH.*0
* @author Joa ix*muVBj.
*/ tvpN/p
publicclass UserManagerImpl implements UserManager { 8,*3zVk-
-?fR|[\[U
private UserDAO userDAO; t!qwxX*$T
Nw pS)6<-
/** 1EsqQz*$u
* @param userDAO The userDAO to set. S{:Cu}o
*/ 7 :U8 f:
publicvoid setUserDAO(UserDAO userDAO){ HeozJ^u\?
this.userDAO = userDAO; r?3Aqi"
} Yqj+hC6>,
$5A^'q
/* (non-Javadoc) ,g|2NjUAc
* @see com.adt.service.UserManager#listUser i}lRIXjdV
0*yJ %
(org.flyware.util.page.Page) [h-norB((
*/ kEP<[K
public Result listUser(Page page)throws (p,}'I#i*
#pA[k-
HibernateException, ObjectNotFoundException { #>[wD#XJV
int totalRecords = userDAO.getUserCount(); zy>}L #
if(totalRecords == 0) C}Qt "-%
throw new ObjectNotFoundException (STx$cya
AC4 l<:Yh
("userNotExist"); x~+-VF3/
page = PageUtil.createPage(page, totalRecords); mi^hvks<
List users = userDAO.getUserByPage(page); S^j,f'2
returnnew Result(page, users); jQ$BPEG&X
} s|2}2<+
PGX+p+wB
} 0>@[o8
$$4W}Ug3U
c-*2dV[@
6+PGwCS
W[|[;{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <L&eh&4c
F,pCR7o>
询,接下来编写UserDAO的代码: ;k}H(QI
3. UserDAO 和 UserDAOImpl: 88o:NJ}_
java代码: c<jB6|.=2
/gw Cwyo
E{>`MNj
/*Created on 2005-7-15*/ *U_oao
package com.adt.dao; q-IWRb0j%a
v8'5pLt"
import java.util.List; F1c&0*_A
=x
H~ww (D
import org.flyware.util.page.Page; 2C1+_IL
"&-C$J5
Id
import net.sf.hibernate.HibernateException; uvv.WbZ
(.Xr#;\(
/** t)r1"oA
* @author Joa D^$OCj\
*/ o,
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publicinterface UserDAO extends BaseDAO { ? OsS`)T
<'2u
a
publicList getUserByName(String name)throws [@2s&Ct;
%h/! Y<%
HibernateException; MGybGbd
@a(oB.i
publicint getUserCount()throws HibernateException; 784;]wdy\
RGp'b
publicList getUserByPage(Page page)throws gp/YjUH7k8
n(R_#,Hs
HibernateException; w1i?#!|
)eR$:uO
} dtTlIhh1V
~6d5zI4\
plXG[1;&G
.Dx2 ;lj
}cW#045es
java代码: T 2|:nC)@
ML=z<u+
oEIqA
/*Created on 2005-7-15*/ Yi Zx{5
package com.adt.dao.impl; ) b:4uK
A
5f_7&NxT
import java.util.List; sN]Z
#7
rPO}6lsc
import org.flyware.util.page.Page; >EIrw$V$
x'i0KF
import net.sf.hibernate.HibernateException; #LWg" i
import net.sf.hibernate.Query; wPH+n-&e
<25ccE9^c
import com.adt.dao.UserDAO; &7Kb]Ti
DL4iXULNY
/** <V
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* @author Joa Qlh?iA
*/ $G3@< BIN
public class UserDAOImpl extends BaseDAOHibernateImpl f3n~{a,[
j38 6gL
implements UserDAO { __(V C:
+-ewE-:|L
/* (non-Javadoc) 0b++17aV
* @see com.adt.dao.UserDAO#getUserByName 5hz_P+Q
@p]UvqtB@
(java.lang.String) 8\_*1h40s
*/ qTy v.#{y
publicList getUserByName(String name)throws K PggDKS
+WLD
HibernateException { $5L(gn[
String querySentence = "FROM user in class 'tuBuYD\
^c'f<<z|7r
com.adt.po.User WHERE user.name=:name"; $W, zO|-
Query query = getSession().createQuery -'ZxN'*%
V16%Ne
(querySentence); f4
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query.setParameter("name", name); 6[+j'pW?
return query.list(); PbN3;c3
} {AgBwBCE
,qu:<
/* (non-Javadoc) s41adw>
* @see com.adt.dao.UserDAO#getUserCount() ]-Lruq#
*/ }!B.K^@)
publicint getUserCount()throws HibernateException { y5%5O xB
int count = 0; m1y `v"
String querySentence = "SELECT count(*) FROM +{*)}[w{x
5rN7':(H!%
user in class com.adt.po.User"; Gh+f1)\FA"
Query query = getSession().createQuery r?$&Z^
JV%nH!Fs
(querySentence); zq=&4afOE
count = ((Integer)query.iterate().next
JWWInuH
U'M|=I'
()).intValue(); Bac| ;+L~L
return count; T 9MzUV&
} ArX]L$D
yxY
h?ka
/* (non-Javadoc) 'M-)Os"
* @see com.adt.dao.UserDAO#getUserByPage vv*
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l7~Pa0qD
(org.flyware.util.page.Page) }5hZo%w[n
*/ R8ZD#,;
publicList getUserByPage(Page page)throws U!NI_uk
kQ[Jo%YT?E
HibernateException { 2-7Z(7G{ F
String querySentence = "FROM user in class mtX31M4
Gw`/.0
com.adt.po.User"; c_DaNEfaY
Query query = getSession().createQuery -R8/`M8GbD
//tT8HX
(querySentence); #/s7\2
query.setFirstResult(page.getBeginIndex()) b=G4MZQ
.setMaxResults(page.getEveryPage()); Yx 3|G
return query.list(); /N%zwj/*
} 5\3 swP_7
m{O
Dz:
} MYu`c[$jZ
-)>(8 f
'}CN?f|.
4UVW#Rw{
1VGpq-4*j
至此,一个完整的分页程序完成。前台的只需要调用 5Kee2s?*
j@CKO cn2
userManager.listUser(page)即可得到一个Page对象和结果集对象 G g(NGT
yZ|+VXO
的综合体,而传入的参数page对象则可以由前台传入,如果用 h,~tXj
$$\V2%v
webwork,甚至可以直接在配置文件中指定。 ^vG=|X|)c
X&.:H~xS+
下面给出一个webwork调用示例: Nuo^+z
E
java代码: ~W3:xnBEk
;/R kMS
LS{bg.e
/*Created on 2005-6-17*/ 0W_mCV
package com.adt.action.user; X*)?LxTj
$8Ig&k|~8
import java.util.List; d~sJ=)
M6&~LI.We=
import org.apache.commons.logging.Log; Yfe'#MKfL
import org.apache.commons.logging.LogFactory; P*7S3Td
import org.flyware.util.page.Page; 73VQ@Jn
#1B}-PGCm
import com.adt.bo.Result; Enu!u~1]F
import com.adt.service.UserService; hAlPl<BO#V
import com.opensymphony.xwork.Action; m|lM.]2_
]~'9
/** aU4R+.M7@
* @author Joa brj[c>ID
*/ , !r@9T
publicclass ListUser implementsAction{ *|^,DGfQ6
;}UzJe ,S
privatestaticfinal Log logger = LogFactory.getLog 'OG{*TDPu
9@Q&B+!
(ListUser.class); 27Cz1[oX
D$QGL I9(
private UserService userService; 3Fgz)*Gu]
)U]:9)
private Page page; qg|Ox*_od"
[A|(A$jl
privateList users; vUqe.?5
4Q@\h=r
/* ed=n``P~}
* (non-Javadoc) IeH^Wm&^
* `|&\e_"DE
* @see com.opensymphony.xwork.Action#execute() s:3aRQ%
*/ J0Jr
BXCh
publicString execute()throwsException{ k&yQ98H$K"
Result result = userService.listUser(page); UmYD]
page = result.getPage(); 1E8$% 6VV
users = result.getContent(); uL
bp.N8
return SUCCESS; (VfwLo>#
} &<`-:x1 2_
u2Y N[|V
/** re]%f"v:5
* @return Returns the page. hH#lTye
*/ pa>p%
public Page getPage(){ axOi5
return page; $y8mK|3.3u
} .#"1bRWpZ
w<Zdq}{jO
/** !X%S)VSMU
* @return Returns the users. X{#bJ
*/ c$.UE
publicList getUsers(){ FMoJ"6Q
return users; Ih(:HFRMq6
} $|rCrak;
[+y&HNf
/** fBf]4@{
* @param page C?8PT/
* The page to set. NS
h%t+XU]
*/ 3T"2S[gT
publicvoid setPage(Page page){ VIb;96$Or
this.page = page; I+*osk
} B^H4Q
4-
j'\>Nn+
/** !&qx7eOSpP
* @param users (qJIu
* The users to set. 9*BoYFw92*
*/ pi|\0lH6W
publicvoid setUsers(List users){ t#a.}Jl
this.users = users; cZ6?P`X
} NAJ '><2
f+{c1fb>s
/** a:=q8Qy
* @param userService $[)6H7!U)
* The userService to set. ThjUiuWe
*/ @mvIt
publicvoid setUserService(UserService userService){ _2wAaJvA
this.userService = userService; joxS+P5#
} Tnf&pu#5
} th5
X?so
C_6GOpl
cR,'o'V/
$Vo/CZW7
8FAT(f//.
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ^!q 08`0
r5D jCV"
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 <9=zP/Q
X'YfjbGo
么只需要: qsD?dHi7
java代码: wYZy e^7
W/b"a? wE{
s.f`.o
<?xml version="1.0"?> B0 6s6Q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >_rzT9gX&
` 52%XI
1.0//EN" "http://www.opensymphony.com/xwork/xwork- =9kj?
u~
F~tm`n8Z
1.0.dtd"> @~JB\j9
3yeK@>C
<xwork> R1II k
!y.ei1diw
<package name="user" extends="webwork- KK@
&q
,Y`'myL8W
interceptors"> x eJ9H~^
!x`;>0
<!-- The default interceptor stack name ,O$Z,J4VL
Mi;}.K0J
--> =6.8bZT\
<default-interceptor-ref qlz( W
lo\: ]/&6
name="myDefaultWebStack"/> pw0Px
|Dl*w/n
<action name="listUser" }@3Ud'
Y
8:Z@ lp^
class="com.adt.action.user.ListUser"> KC&H*
<param SNQz8(O
59&T