Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 yM,.{m@F<
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 *<HA])D,
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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 CgT5sk}
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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 B:mtl?69g
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。 ,4W~CkLD
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分页支持类: xWRkg$A
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java代码: 3R|UbG`
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package com.javaeye.common.util; GZxPh&BM?
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import java.util.List; r4MPs-}oF
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publicclass PaginationSupport { Q*jNJ^IW
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publicfinalstaticint PAGESIZE = 30; y@XE! L
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privateint pageSize = PAGESIZE; TmviYP gb
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privateList items; G^1 5V'*
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privateint totalCount; <@.!\
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privateint[] indexes = newint[0]; 9 AWFjoXl"
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privateint startIndex = 0; =Ju%3ptH0
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public PaginationSupport(List items, int aHR+4m~)
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totalCount){ } "QL"%
setPageSize(PAGESIZE); Wf!u?nH.5
setTotalCount(totalCount); $y$E1A6h+
setItems(items); Z Jgy!)1n
setStartIndex(0); \Gl>$5np
} `8 Ann~Z|k
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public PaginationSupport(List items, int Q]1s*P
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totalCount, int startIndex){ 5M v<8P~
setPageSize(PAGESIZE); QZwZ4$jkiO
setTotalCount(totalCount); sgLw,WZ:
setItems(items); 99GK6}~TGm
setStartIndex(startIndex); S1I# qb
} GI5#{-)
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public PaginationSupport(List items, int Q30TR
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totalCount, int pageSize, int startIndex){ `RlMfd
setPageSize(pageSize);
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setTotalCount(totalCount); ]mR!-Fqj
setItems(items); \"7U,y',
setStartIndex(startIndex); 'w"hG$".
} Xk>YiV",?
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publicList getItems(){ )z\ 73|w
return items; 1j_
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} @
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publicvoid setItems(List items){ ?Gnx!3Q
this.items = items; Ud:;kI%Vj
} X..<U}e
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publicint getPageSize(){ aY8QYK ;?^
return pageSize; Oil~QAd,
} ruU &.mZ
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publicvoid setPageSize(int pageSize){
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this.pageSize = pageSize; =#T3p9
} X1XmaO%A
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publicint getTotalCount(){ 6f*QUw~
return totalCount; F\2<q$Zn+
} 06]%$-j
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publicvoid setTotalCount(int totalCount){ +JejnG0
if(totalCount > 0){ Ake$M^Bz
this.totalCount = totalCount; Yln[ZmK9g
int count = totalCount / !NO)|N>
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pageSize; /k.?x] Ab
if(totalCount % pageSize > 0)
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count++; '/F%
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indexes = newint[count]; 2-dEie/{'
for(int i = 0; i < count; i++){ quL+UFuM
indexes = pageSize * 7r{159&=
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i; 6<o2 0(?
} MLvd6tIv,
}else{ kYZj^tR
this.totalCount = 0; HhB&vi
} )}to7r7`
} 9P& \2/ {
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publicint[] getIndexes(){ !BDJU
return indexes; R*O<(
} J-ErG!
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publicvoid setIndexes(int[] indexes){ B-oQjr-
this.indexes = indexes; $u cmE
} 7v
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publicint getStartIndex(){ avb'dx*q>
return startIndex; =sUrSVUeU
} .cK<jF@'
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publicvoid setStartIndex(int startIndex){ x"~gulcz
if(totalCount <= 0) b[^|.>b
this.startIndex = 0; glomwny
elseif(startIndex >= totalCount) 2CRgOFR
this.startIndex = indexes JIXZI\Fk
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[indexes.length - 1]; TJ>$ ~9&Sy
elseif(startIndex < 0) :~Ppv5W.
this.startIndex = 0; i#%!J:_=
else{ ^WUG\@B
this.startIndex = indexes e"cvo(}g
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[startIndex / pageSize]; d`3>@*NR<
} $Dm|ol.Z
} h3Y|0-D
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publicint getNextIndex(){ \t
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int nextIndex = getStartIndex() + ;4<!vVf e
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pageSize; Q\pI\]p:
if(nextIndex >= totalCount) X< 4f7;]O
return getStartIndex(); tY- `$U@
else aucG|}B
return nextIndex; %
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} [orS-H7^
)\+1*R|H}
publicint getPreviousIndex(){ "H|hN
int previousIndex = getStartIndex() - ;:aCZ8e
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pageSize; |W*i'E
if(previousIndex < 0) xeW}`i5_w
return0; evlz R/
else f,VJfY?#
return previousIndex; c^7QiTt_
} z4r g.ai
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} Qsg([K
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抽象业务类 p9gX$-!pbG
java代码: \*\ )zj*r
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i
/** 6tN!]
* Created on 2005-7-12 QygbfW6u
*/ +K:hetv
package com.javaeye.common.business; PDhoCAh
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import java.io.Serializable; =-;J2Qlg6
import java.util.List; oT*qMLdn
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import org.hibernate.Criteria; c;7`]}fGu
import org.hibernate.HibernateException; x%%OgO+>
import org.hibernate.Session; tjbI*Pw7(
import org.hibernate.criterion.DetachedCriteria; _e$T'*q
import org.hibernate.criterion.Projections; Qn`Fq,uvL
import S\ ) ~9?
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org.springframework.orm.hibernate3.HibernateCallback; VP_S[+Zv~
import W*9*^
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org.springframework.orm.hibernate3.support.HibernateDaoS AZfW
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upport; xnPi'?A]
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import com.javaeye.common.util.PaginationSupport; ehyCAp0oI
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public abstract class AbstractManager extends M6H#Y2!ZbC
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HibernateDaoSupport { &'oZ]}^0
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privateboolean cacheQueries = false; DGO\&^GT^
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privateString queryCacheRegion; O9R[F
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publicvoid setCacheQueries(boolean {vU;(eN
0 ![
cacheQueries){ T[eb<
this.cacheQueries = cacheQueries; !EB[Lutm
} 3pjK`"Nmz\
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publicvoid setQueryCacheRegion(String 1Y{pf]5Wx
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queryCacheRegion){ #SqU>R
this.queryCacheRegion = I3d!!L2ma
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queryCacheRegion; /7hC
/!@
} 'ARbJ1a
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publicvoid save(finalObject entity){ OtZc;c
getHibernateTemplate().save(entity); ;ji["b
} r"&VG2c0K
% jSB9
publicvoid persist(finalObject entity){ UzT"Rb:e
getHibernateTemplate().save(entity); DgODTxiX
} N~+ e\K6
< m/@_"
publicvoid update(finalObject entity){ 10{zF_9yx
getHibernateTemplate().update(entity); KYR64[1
} !M;><b}=5
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publicvoid delete(finalObject entity){ k@>y<A{;D
getHibernateTemplate().delete(entity); @w73U;9\
} 1i/&t[
Lb} $)AcC
publicObject load(finalClass entity, GDY=^r
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finalSerializable id){ ]h?p3T$h
return getHibernateTemplate().load N^%7
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(entity, id); 4#lOAzDtv
} aM|;3j1p
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publicObject get(finalClass entity, mY&(&'2T"
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finalSerializable id){ Sd+bnq%
return getHibernateTemplate().get ^]X\boWlI
' ?uwUBi
(entity, id); rObg:(z&\
} qaiR329fx
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publicList findAll(finalClass entity){ dzs(sM=
return getHibernateTemplate().find("from #H.DnW
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" + entity.getName()); xP-\)d-.aN
} 1fqJtP6
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publicList findByNamedQuery(finalString N;R I
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namedQuery){ 0[.T`tpN'
return getHibernateTemplate a~&euT2
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().findByNamedQuery(namedQuery); ?g9oiOhnG
} u#nM_UJe
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publicList findByNamedQuery(finalString query, /Suh&qw>
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finalObject parameter){ og`K!d~
return getHibernateTemplate CkR
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().findByNamedQuery(query, parameter); i)=
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} JVR,Py:%G
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publicList findByNamedQuery(finalString query, Hv-f :P O
Dbw{E:pq
finalObject[] parameters){ JS^!XB'!
return getHibernateTemplate %/w%A:y#&
)8%m|v#W
().findByNamedQuery(query, parameters); v,d'SR.
} /wU4^8Hz
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publicList find(finalString query){ 0SV4p.
return getHibernateTemplate().find "P a y2
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(query); r<5i
} Y|cj&<o
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publicList find(finalString query, finalObject 47!k!cHa
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parameter){ E7 P'}
return getHibernateTemplate().find ffR<G&"n~b
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(query, parameter); nrKir
} +g&M@8XO&
){4 !
public PaginationSupport findPageByCriteria zKfY0A R
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(final DetachedCriteria detachedCriteria){ EIF"{,m
return findPageByCriteria 6cXZ3;a
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); {
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} [r^WS;9n
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public PaginationSupport findPageByCriteria Ie(M9QMp
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(final DetachedCriteria detachedCriteria, finalint rA /T>ZM
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startIndex){ a+<{!+3v
return findPageByCriteria sp6A*mwl
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(detachedCriteria, PaginationSupport.PAGESIZE, _2X6c,
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startIndex); X3m)
} }aL&3[>>
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public PaginationSupport findPageByCriteria B^Hhrz!
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(final DetachedCriteria detachedCriteria, finalint (}
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pageSize, `5SQ4
finalint startIndex){ HL%|DCo
return(PaginationSupport)
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getHibernateTemplate().execute(new HibernateCallback(){ H18pVh
publicObject doInHibernate S]?I7_
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(Session session)throws HibernateException { m8Rt>DY
Criteria criteria = $Y[C A.F
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detachedCriteria.getExecutableCriteria(session); Z@0IvI
int totalCount = 4e?MthJ>
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((Integer) criteria.setProjection(Projections.rowCount UZ!It>
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()).uniqueResult()).intValue(); FiKGB\_]
criteria.setProjection BK1I_/_!
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(null); C);I[H4Yfw
List items = @s0 mX3P
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criteria.setFirstResult(startIndex).setMaxResults ^bECX<,H
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(pageSize).list(); ''}2JJU{
PaginationSupport ps = 3cc;BWvM
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new PaginationSupport(items, totalCount, pageSize, o\X|\nUk
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startIndex); dst!VO:
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return ps; bJ]blnH
} B1TWOl?d{
}, true); B? 9"Ztb
} _Zus4&'
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public List findAllByCriteria(final ')ZZ)&U>z
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DetachedCriteria detachedCriteria){ >3&9Wbv>
return(List) getHibernateTemplate \"b'Z2g
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().execute(new HibernateCallback(){ xn anca
publicObject doInHibernate ?N&s.
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(Session session)throws HibernateException { w,LB
Criteria criteria = cG{
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detachedCriteria.getExecutableCriteria(session); ])?[9c
return criteria.list(); ZUS06#t}
} m}'!W`<
}, true); ppnl bL^*
} + aWcK6
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public int getCountByCriteria(final ;<#=|eD2
@ssT$#)$!
DetachedCriteria detachedCriteria){ ]>[0DX]j
Integer count = (Integer) j+Q+.39s-~
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getHibernateTemplate().execute(new HibernateCallback(){ &3:<WU:U
publicObject doInHibernate =oTj3+7
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(Session session)throws HibernateException { C)ic;!$Qhb
Criteria criteria = V6_~"pRR=
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detachedCriteria.getExecutableCriteria(session); w`[`:H_z
return 5Q,j+
9>;CvR
criteria.setProjection(Projections.rowCount &t}6sD9o
"p[3^<~uQ
()).uniqueResult(); Y)7\h:LIg
} I2z6iT4nB
}, true); XW:%YTv
return count.intValue(); BOv ^L?)*Z
} WQMoAPfqL
} <4TF ]5
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用户在web层构造查询条件detachedCriteria,和可选的 S7j U:CLJ
\zhCGDm1_
startIndex,调用业务bean的相应findByCriteria方法,返回一个 oWq]\yT<`
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PaginationSupport的实例ps。 NG:
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ps.getItems()得到已分页好的结果集 9r
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ps.getIndexes()得到分页索引的数组 'r rnTd c
ps.getTotalCount()得到总结果数 AI-ZZ6lzR
ps.getStartIndex()当前分页索引 fJ+4H4K
ps.getNextIndex()下一页索引 lXXWQ=
ps.getPreviousIndex()上一页索引 YMj iJTl
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: :928y
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 @{ L|&Mk!
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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 'N`x@(
=69sWcC8
一下代码重构了。 @XVx{t;g2
czK}F/Sg `
我把原本我的做法也提供出来供大家讨论吧: 7A{Z1[7
seb/rxb
首先,为了实现分页查询,我封装了一个Page类: (^m~UN2@~m
java代码: eF?jNO3
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/*Created on 2005-4-14*/ IiV]lxiE]
package org.flyware.util.page; QT4vjz+|
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/** 57EL&V%j
* @author Joa z6fY_LL
* 6iY(RYZ7-
*/ :0p$r
pJP
publicclass Page { {x~r$")c?
[-^xw1:
/** imply if the page has previous page */ rr2^sQ;_
privateboolean hasPrePage; uJa.]J~L=
<&HHo>rl
/** imply if the page has next page */ ]+>Kl>@
privateboolean hasNextPage; 0CI\Yd=
%K0Wm#)
/** the number of every page */ jVna;o)
privateint everyPage; 7?8+h
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/** the total page number */ )Jh:~9L%='
privateint totalPage; tO3#kV\,
IV%Rph>d
/** the number of current page */ z }Vg4\x&
privateint currentPage; 0|,Ij$
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/** the begin index of the records by the current 3pyE'9"f6
4W=fQx]
query */ fIn^a3TV
privateint beginIndex; O2/_$i[F
| NyANsI
8J~-|<Q6
/** The default constructor */ g|j15&x
public Page(){ /&l4 sF1
34L1Gxf
} PB~
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/** construct the page by everyPage 3~Ll<8fv
* @param everyPage \T?6TDZ]
* */ l!:L<B
public Page(int everyPage){ m@YK8c#$
this.everyPage = everyPage; !PgwFJ
} Us_1 #$p,
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/** The whole constructor */ H% FP!03
public Page(boolean hasPrePage, boolean hasNextPage, 9{Igw"9ck
3il$V78|
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int everyPage, int totalPage, bd2QQ1[1vh
int currentPage, int beginIndex){ znAo]F9=J"
this.hasPrePage = hasPrePage; ep{/m-h(!_
this.hasNextPage = hasNextPage; z Ece>=C
this.everyPage = everyPage; H`jnChD:M'
this.totalPage = totalPage; 77'@U(
this.currentPage = currentPage; YR[I,j
this.beginIndex = beginIndex; 9xeg,#1
} gOMy8w4>
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/** DX ZZZ[#
* @return L0Ajj=
* Returns the beginIndex. 3Te&w9K
*/ 1!
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publicint getBeginIndex(){ Cv;#8Wj}
return beginIndex; yTf/]H]d
} B &3sV+
H%0WD_
/** yi2F#o 'K
* @param beginIndex 3CPSyF
* The beginIndex to set. gw$?&[wY
*/ Lz!H@)-mr
publicvoid setBeginIndex(int beginIndex){ EXR6Vb,
this.beginIndex = beginIndex; u(8dsgR
} 6#ktw)e
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/** 4~2 9,
* @return t_+owiF)M
* Returns the currentPage. B_RF)meux
*/ &ViK9
publicint getCurrentPage(){ fZQ2<*)pqO
return currentPage; Z6&bUZF$bE
} AEUR`.
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/**
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* @param currentPage ^FZ9q
* The currentPage to set. +^%)QH>9
*/ w*X(bua@
publicvoid setCurrentPage(int currentPage){ uH#X:Vne
this.currentPage = currentPage; V{X/y N.u
} =Z..&H5i
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/** "BIhd*K[~
* @return ]`|;ZQiD
* Returns the everyPage. bD?gwhAKA
*/ 8t|?b
publicint getEveryPage(){ ! vuun |
return everyPage; @~FJlG(n
} 2>f3nW
W*/2x8$d
/** gLlA'`!
* @param everyPage n6 wx/:
* The everyPage to set. y( UWh4?t
*/ E:[!)UG|y
publicvoid setEveryPage(int everyPage){ !e+Sa{X
this.everyPage = everyPage; M~)iiKw~MY
} W{1l?Wo
8"rK
/** -![{Zb@
* @return V0n8fez
b
* Returns the hasNextPage.
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*/ O2xqNQ`d
publicboolean getHasNextPage(){ n^nQrRIp
return hasNextPage; L@J$kqWY
} UJjtDV3@_g
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/**
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* @param hasNextPage y,`q6(&
* The hasNextPage to set. ygd*zy9
*/ %&J`mq
publicvoid setHasNextPage(boolean hasNextPage){ #%{
this.hasNextPage = hasNextPage; _>^Y0C[?5
} BM5)SgK
~+PK Ws'}F
/** lB7/oa1]>
* @return iz+,,UH
* Returns the hasPrePage. }4Q3S1|U
*/ v!=e]w6{
publicboolean getHasPrePage(){ Z1p%6f`
return hasPrePage; w9Nk8OsL
} &SPIu,
M
#%V%<
/** pV1;gqXNS
* @param hasPrePage 0*j\i@
* The hasPrePage to set. ^ '_Fd
*/ &E@mCQ1
publicvoid setHasPrePage(boolean hasPrePage){ aHPx'R
this.hasPrePage = hasPrePage; Y5*A,piq
} $4kbOqn4
dvglh?7d
/** !:~C/B{
* @return Returns the totalPage. QaXdO=3
* [=:4^S|M
*/ N9vNSmm
publicint getTotalPage(){ wQM( |@zE}
return totalPage; W k "_lJ
} |aj]]l[@S
H~:g=Zw
/** V'9OGn2v
* @param totalPage slLTZ]
* The totalPage to set. xscR Bx
*/ ~8'HX*B]z
publicvoid setTotalPage(int totalPage){ |1Nz8Vr.
this.totalPage = totalPage; ^5+7D1>W%
} iphdJZ/f
%v^qQWy=*
} &m{~4]qWpM
"*KOU2}C
hJX;/~L
F |_mCwA
v'Up& /(
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 z[JM ]Wy
}(WUZ^L
个PageUtil,负责对Page对象进行构造: 5UQ[vHMqI
java代码: S Z &[o&H
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dhuIVBp!!e
/*Created on 2005-4-14*/ uuy0fQQ8ti
package org.flyware.util.page; - @KT#
SQk5SP
import org.apache.commons.logging.Log; z] |Y
import org.apache.commons.logging.LogFactory; qLB(Th\&'
/#}%c'
/** 7/\SN04l
* @author Joa / $'M
* ])WIw'L!
*/ RC!T1o~L
publicclass PageUtil { 6X$\:>
XLm@, A[
privatestaticfinal Log logger = LogFactory.getLog " j:15m5
_$v$v$74^
(PageUtil.class); ^AO2%09.S
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/** 1z3I^gI*i
* Use the origin page to create a new page l_(4CimOZ
* @param page |D8c=c%
* @param totalRecords |8\et
* @return n>%TIoY
*/ >~&7D`O
publicstatic Page createPage(Page page, int Bv`3T Af2
*y W9-(
totalRecords){ +R31YR8C0
return createPage(page.getEveryPage(), ZaFqGcS~
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page.getCurrentPage(), totalRecords); dW#l3_'3T
} y{nX 6
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/** EtcXzq>w
* the basic page utils not including exception v2mqM5Z
jF5oc
handler L/O:V^1
* @param everyPage 1:"ZS ]i
* @param currentPage
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* @param totalRecords 4_\]zhS
* @return page dr4 m}v.
*/ E+eC #!&w
publicstatic Page createPage(int everyPage, int l3kBt-m
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currentPage, int totalRecords){ m RtE~~p
everyPage = getEveryPage(everyPage); uTP4r
currentPage = getCurrentPage(currentPage); Y FW0
int beginIndex = getBeginIndex(everyPage, %W$?*Tm
6r)qM)97
currentPage); 1;+(HB
int totalPage = getTotalPage(everyPage, q5~fU$ ,
1)M%]I4
totalRecords); ]&L[]
boolean hasNextPage = hasNextPage(currentPage, 3a,7lTUuB
hfQ^C6yR
totalPage); wW^3/
boolean hasPrePage = hasPrePage(currentPage); C#.d
sl
B4 # gT
returnnew Page(hasPrePage, hasNextPage, Yc
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everyPage, totalPage, 6j~'>w(F
currentPage, H3o Um1
7ZgFCK,8m,
beginIndex); h}P""
} bC]GL$ph9*
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privatestaticint getEveryPage(int everyPage){ #'kVW{
return everyPage == 0 ? 10 : everyPage; YCB=RT]&`
} 3 jay V
?I#zcD)w
privatestaticint getCurrentPage(int currentPage){ `LVX|l62
return currentPage == 0 ? 1 : currentPage; FYeUz$/
} `)eqTeW
aAkO>X%[
privatestaticint getBeginIndex(int everyPage, int 1He'\/#
RIxGwMi%
currentPage){ )Y,>cg:z~
return(currentPage - 1) * everyPage; ^2um.`8
} NU|T`gP
[a1}r=6~
privatestaticint getTotalPage(int everyPage, int 'q=Ly?9
q P>Gre
totalRecords){ :. a}pgh
int totalPage = 0; 1:lhZFZ
v#`P?B\
if(totalRecords % everyPage == 0) s&zg!~@5b
totalPage = totalRecords / everyPage; cwA+?:Ry}
else p[-buB]
totalPage = totalRecords / everyPage + 1 ; EK}f-Xei
DvvjIYB~
return totalPage; zi}dQsy6
} -|xyj2M
g4*]R>f
privatestaticboolean hasPrePage(int currentPage){ 20H$9M=}
return currentPage == 1 ? false : true; vZpt}u
} W%RjjLJ@
{ sL(PS.z
privatestaticboolean hasNextPage(int currentPage, ? k*s!YCZ
O
WVa&8O
int totalPage){ Y:XxTa*
return currentPage == totalPage || totalPage == `l95I7
A?*_14&
0 ? false : true; .pQ4#AJ
} &llp*<
i7
9rsty{J8
h $}&N
} j*jO809%^
I 0}+}{M:
E6d0YgfD
n/5)}( }K
HLcK d`$/
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。 &Q"Ox{~W
'\X<+Sm'
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 ef=LPCi?
VZ8HnNAbX
做法如下: Ni[2 p
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 @cZNoD
Yxt`Uvc(^h
的信息,和一个结果集List: YQ}bG{ V
java代码: Iz\IQa
PO[
AP%;
)0JXUC e
/*Created on 2005-6-13*/ dF%sD|<)
package com.adt.bo; %Ot^G%34
~Xg@,?Zr
import java.util.List; 2*K _RMr~
7.PG*q
import org.flyware.util.page.Page; z`D;8x2b
ggUJ -M'2h
/** n1xN:A
* @author Joa ?qt>;o|Ue
*/ 8j}CP
publicclass Result { 4W9#z~'
5? `*i"
private Page page; W=Ru?sG=
Q1Sf7)
private List content; X,<n|zp
^ cn)eA
/** `AA[k
* The default constructor =%YU~
*/ 5/v@VUzH
public Result(){ .)>DFGb>H
super(); 1dF=BR8
} KN;b+`x;M
hYW<4{Gjr
/** DM%4V|F"
* The constructor using fields PZRm.vC)k
* %<q l
* @param page gekW&tRie
* @param content b"y][5VE
*/ =M'y& iz-
public Result(Page page, List content){
ajayj|h
this.page = page; A({8p
this.content = content; nJ`JF5tI
} &zr..i4O
8qfg=mu+%
/** ZgL4$%
* @return Returns the content. MeqW/!72$L
*/ Fa$ pr`
publicList getContent(){ qsUlfv9L6
return content; 7
Znr2I
} \KmjA)(
eGS1% [
/** MH`H[2<\!,
* @return Returns the page. 0SXWt? }
*/ hgCeU+ H
public Page getPage(){ 0.-2FHc9L
return page; c ZN+D D
} "]ow1{
[g_Cg=J
/** Z_Ox '
* @param content O1Gd_wDC/i
* The content to set. SB1\SNB
*/ @O<kjR<b
public void setContent(List content){ Eoug/we
this.content = content; ;K[`o/#4"
} Q9N=yz
1\q2;5
/** Uc6BI$Fmz
* @param page kn_%'7
* The page to set. m-lUgx7
*/ yG5T;O&
publicvoid setPage(Page page){ #_}lF<k
this.page = page; zm}4=Kz}
} UB]}j^
} b<qv
/t)$
_gK@),de
w8*+l0
1%|+yu1
^{["]!f#
2. 编写业务逻辑接口,并实现它(UserManager, Ep0L51Q
Z'PE^ ,
UserManagerImpl) l
tr=_
java代码: KE+y'j#C3
!JjB,1
>b#z
o,
/*Created on 2005-7-15*/ qx<`Kc4
package com.adt.service; lztPexyXZ
lcij}-z:%e
import net.sf.hibernate.HibernateException; 3ryIXC\v
W?!(/`J]
import org.flyware.util.page.Page; W{l+_a{/9
MN|y5w}$u
import com.adt.bo.Result; lDNB0Ad
J4h7]
qt
/** |QJ!5nb
* @author Joa $!Z6?+
*/ %O;"Z`I
publicinterface UserManager { iLn)Z0<\o
b7{)B?n
public Result listUser(Page page)throws ="RDcf/
OC9_EP\"
HibernateException; !SIGzj
|]~tX zY
} A"k6n\!n;
Aj.TX%}`h
nI%0u<=d
;Br8\2=$
kssS,Ogf\_
java代码: g.X?wyg5
$BG4M?Y
y@'8vOh`
/*Created on 2005-7-15*/ {IJV(%E
package com.adt.service.impl; +/7UM x1
V<
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import java.util.List; [a\:K2*'
Lw?4xerLsb
import net.sf.hibernate.HibernateException; =L9sb!
ErJi
import org.flyware.util.page.Page; ' eO4h^
import org.flyware.util.page.PageUtil; Mi9A%ZmP
bV&/)eqv
import com.adt.bo.Result; a_m P$4T
import com.adt.dao.UserDAO; 4s~YqP{K
import com.adt.exception.ObjectNotFoundException; IP$^)t[
import com.adt.service.UserManager; D,d mlv
Yva^JB
/** 3'O+
* @author Joa 5[esW
*/ !zwnFdp
publicclass UserManagerImpl implements UserManager { ~N;.hU%l
TS)p2#
private UserDAO userDAO; Vp\BNq_!s
=U!'v X d
/** CN\SxK`,
* @param userDAO The userDAO to set. xZjD(e'
*/ |Rw0$he
publicvoid setUserDAO(UserDAO userDAO){ C
7YZ;{t
this.userDAO = userDAO; b4!(~"b.
} AYd7qx:~
0tm%Kd
/* (non-Javadoc) :S0r)CNP
* @see com.adt.service.UserManager#listUser Z,qo
jtw
$.(%7[
(org.flyware.util.page.Page) }]N7CWy
*/ %F9%t
public Result listUser(Page page)throws zFqH)/
&4sUi K"
HibernateException, ObjectNotFoundException { ej4 7'#EY
int totalRecords = userDAO.getUserCount(); /d9I2~}B
if(totalRecords == 0) c~b[_J)
throw new ObjectNotFoundException !v<r=u
)?joF)
("userNotExist"); l.\Fr+*ej
page = PageUtil.createPage(page, totalRecords); [Oe$E5qv)]
List users = userDAO.getUserByPage(page);
pMYEL
returnnew Result(page, users); Fd2Eq&:en$
} w#U3h]>,
/_l%Dm?
} muo(bR8
bdk"7N
Y2!OJuyGc
j?29_Az
C,hs!v6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 uJA8PfbD
`MlQPLH
询,接下来编写UserDAO的代码: kB_G L>fc
3. UserDAO 和 UserDAOImpl: jn>3(GRGC$
java代码: E< "aUnI
k'&BAC.K,
rXuhd [!(P
/*Created on 2005-7-15*/ o"R[#E&Yx
package com.adt.dao; $`.7XD}
DbP!wU lqR
import java.util.List; mEv<r6qDT
VmHok
import org.flyware.util.page.Page; di>"\On-
2B3H-`
import net.sf.hibernate.HibernateException; !
pR&&uG
J "yO\Y
/** >B U0B
* @author Joa thDQ44<#)
*/ s[NkPh9&
publicinterface UserDAO extends BaseDAO { kjfZ*V=-
2aX|E4F
publicList getUserByName(String name)throws Jm0P~E[n
'}e_8FS
HibernateException; S=~[ 6;G
>K1)XP
publicint getUserCount()throws HibernateException; RmY5/IYR|:
b%L8mX
publicList getUserByPage(Page page)throws TDs=VTd@Z
B/:q
HibernateException; !JzM<hyg3
fchsn*R%-
} n@XI$>B
B^P)(Nu+
UX;?~X
*BH*
X#'DS&{
java代码: L/_h5Q:'W
F$ShhZgi
V$VqYy9 *
/*Created on 2005-7-15*/ ?>cx;"xF
package com.adt.dao.impl; LdwWB
`L
I?uU}NK
import java.util.List; %%)"W
n#`
>0DQ<@ot:
import org.flyware.util.page.Page; Z,)4(#b =
!?Gt5$f
import net.sf.hibernate.HibernateException; ?OW
4J0B'
import net.sf.hibernate.Query; \ ,ARYwd
Ci4`,
import com.adt.dao.UserDAO; VdjS\VYe,
H=9kDP${
/** ExeD3Zj
* @author Joa =,$*-<p=3
*/ R8I%Cyc
public class UserDAOImpl extends BaseDAOHibernateImpl SE.r 'J0
KiAWr-~gJ
implements UserDAO { kfr' P u
E;/WP!/.
/* (non-Javadoc) p:Ry F4{b2
* @see com.adt.dao.UserDAO#getUserByName QMLz
1"YN{Ut;G
(java.lang.String) 1fm4:xHH
*/ r/}q=J.
publicList getUserByName(String name)throws 3}(6z"r
C]414Ibi
HibernateException { GK.^Gd
String querySentence = "FROM user in class FM;NA{
_8A
com.adt.po.User WHERE user.name=:name"; z`$jxSLm
Query query = getSession().createQuery yiO!ZT
nNz1gV:0X
(querySentence); ]6L;
query.setParameter("name", name); DXBc 7J
return query.list(); _QBN/KE9
} V
6I77z
fI"sdzu^
/* (non-Javadoc) O2;FaASF
* @see com.adt.dao.UserDAO#getUserCount() _; !7:'J
*/ 7'Z-VO
publicint getUserCount()throws HibernateException { iGB1f*K%x
int count = 0; *;t\!XDgp
String querySentence = "SELECT count(*) FROM 0`c|ZzY
VK*Dm:G0
user in class com.adt.po.User"; V[ju7\>$Z
Query query = getSession().createQuery 86Hg?!<i.
.a2b&}/.d
(querySentence); (
m/ujz
count = ((Integer)query.iterate().next :B{Wf 2<z
`NYu|:JK:
()).intValue(); "@^Pb$BLY
return count; 8C]K36q
} )Tjh
@W}cM
/* (non-Javadoc) Q2yD4>qy
* @see com.adt.dao.UserDAO#getUserByPage Z,zkm{9*
}py)EI,U
(org.flyware.util.page.Page) B-^r0/y;
*/ kvcDa+#
publicList getUserByPage(Page page)throws W*S}^6ZT`
"| Oj!&0
HibernateException { pHQrjEF*
String querySentence = "FROM user in class +7\$wc_1I@
g)$/'RB
com.adt.po.User"; \]C_ul'
Query query = getSession().createQuery "uCO?hv0
J,4,#2M8
(querySentence); }Q$}LR@
query.setFirstResult(page.getBeginIndex()) (xpt_]Q!H
.setMaxResults(page.getEveryPage()); J^<Gi/:*^
return query.list(); Drm#z05i[g
} RO+ jVY~H-
Ov8^6O
}
P.bxq50
JLd-{}A""-
Gyx4}pV
/tm2b<G
n(I,pF
至此,一个完整的分页程序完成。前台的只需要调用 "DaE(S&
"&Hr)yyWG
userManager.listUser(page)即可得到一个Page对象和结果集对象 a-e_ q
Q$+6f,m#W
的综合体,而传入的参数page对象则可以由前台传入,如果用 u7&q(Z&&O
+YZ*>ki
webwork,甚至可以直接在配置文件中指定。 F m?j-'
b@ QCdi,u
下面给出一个webwork调用示例: <fHJ9(5$V
java代码: 7Tb[sc'
^'9.VVyz
w*?SGW
/*Created on 2005-6-17*/ %xt;&HE
package com.adt.action.user; Q,nJz*AJ
+3uPHpMB-
import java.util.List; T@wgWE<0y_
5{/uHscwLa
import org.apache.commons.logging.Log; 5(zdM)Y7
import org.apache.commons.logging.LogFactory; Q
XSS
import org.flyware.util.page.Page; |I[/Fl:
"; 1@f"kw
import com.adt.bo.Result; P ~ :
N
import com.adt.service.UserService; g(_xo\
import com.opensymphony.xwork.Action; "QD>m7
"I3
#/~q
/** 8Y4mTW
* @author Joa vA3wn><
*/ dx@|M{jz'
publicclass ListUser implementsAction{ Mj&G5R~_
s$% t2UaV
privatestaticfinal Log logger = LogFactory.getLog Hr_5N,
{V,aCr
(ListUser.class); azz=,^U#
|\zzOfaO
private UserService userService; zu3Fi= |0
(>
W\Nf
private Page page; X=+|(A,BdY
VwudNjL
privateList users; 0~~yYo&
\q($8<
/* {xAd>fGG+y
* (non-Javadoc) vPz$+&{I
* y\omJx=,
* @see com.opensymphony.xwork.Action#execute() e2e!"kEF
*/ ;FQNO:NP
publicString execute()throwsException{ NbC2N)L4
Result result = userService.listUser(page); KomMzG:
page = result.getPage(); [
*Dj7zt:
users = result.getContent(); y8_$YA/g
return SUCCESS; b)@D@K"5
} ?3lAogB
+Xp1=2Mq
/** zuu<;^/R
* @return Returns the page. :YQI1 q[6
*/ ~-<MoCm!
public Page getPage(){ 2X<%BFsE
return page; %x.du9
} ]1FLG*sB
TjDtNE
/** ^U5Qb"hz
* @return Returns the users. jST4O"DjM
*/ 35Fxzj $
publicList getUsers(){ 42~.N=2
return users; )X;051Q
} j+fib} 8}
J5(0J7C
/** iciKjXJ:
* @param page NRny]!
* The page to set. xP_/5N=f
*/ *Y?oAVkz
publicvoid setPage(Page page){ 4(*PM&'R
this.page = page; r;xy/*%Mtj
} &<x.D]FA]
99.F'Gz
/** D2g/P8.<A
* @param users d<+hQ\BF,
* The users to set. w
>2sr^!y
*/ 8\"Gs z
publicvoid setUsers(List users){ Y)DAR83
this.users = users; }zks@7kf
} Unv'm5/L
L2+cVR
/** y>.t[*zT
* @param userService ;DSH$'1i
* The userService to set. n\)1Bz
*/ <}:` Y"
publicvoid setUserService(UserService userService){ iGSA$U P|
this.userService = userService; Y/6>OD
}
`!t-$i
} ~|9VVeE
#CPLvg#
7UY4* j|[C
~;?<OOt|wG
rf-yUH]&S
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, 4d%0a%Z
gyD ;kn\CP
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 i(pHJP:a:
2,dWD<h
么只需要: T\n6^@.>
java代码: D
HT^.UM28
/2zan}
Pw| h`[h
<?xml version="1.0"?> F@k}p-e~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $&&E[JY
5?F5xiW
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ^P^%Q)QXl
e*qGrg (E
1.0.dtd"> M,S'4Szuk
$%q=tn'EX
<xwork> ;:j1FOj
EwX&Cj".
<package name="user" extends="webwork- vue^bn
*
eC[74Kng
interceptors"> \7i_2|w
;<N:! $p
<!-- The default interceptor stack name m)} 01N4
tnaFbmp
--> cLl~4jL
<default-interceptor-ref u*v<