Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ^b %8_?2m
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根
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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 :Qo
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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 34Khg
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分页支持类: \=_q{
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java代码: 3og$'#6P
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package com.javaeye.common.util; E}9ldM=]s
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import java.util.List; zxUj1
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publicclass PaginationSupport { Pm(:M:a
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publicfinalstaticint PAGESIZE = 30; GPLt<K!<#
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privateint pageSize = PAGESIZE; DF|s,J`98
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privateList items; E2H<{Q
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privateint totalCount; _j\=FJz[
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privateint[] indexes = newint[0]; ]NV ]@*`tO
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privateint startIndex = 0; "ak9LZQ9z
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public PaginationSupport(List items, int /JubiLEK
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totalCount){ $YY)g$
setPageSize(PAGESIZE); X/K)kIi
setTotalCount(totalCount); 'Sy *'&
setItems(items); -Dxhq&
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setStartIndex(0); #x@lZ! Y
} etMh=/NFV
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public PaginationSupport(List items, int IKzRM|/
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totalCount, int startIndex){ 6*aa[,>
setPageSize(PAGESIZE); u<=KC/vZe
setTotalCount(totalCount); "Lq|66
setItems(items); JOx,19r
setStartIndex(startIndex); t{8v(}
} 5vX8mPR_
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public PaginationSupport(List items, int _s^:zPl
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totalCount, int pageSize, int startIndex){ qJXsf M6
setPageSize(pageSize); Wo9psv7.
setTotalCount(totalCount); Tb1}XvZ
setItems(items); ]ZzG!7
setStartIndex(startIndex); L@n6N|[_
} F:o#
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publicList getItems(){ X0Z-1bs
return items; -F+P;S
} =ch
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publicvoid setItems(List items){ m_!vIUOz
this.items = items; Jp3di&x
} &M3ES}6
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publicint getPageSize(){ 0SYf<$
return pageSize; DxKfWb5 R
} w-H%B`/
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publicvoid setPageSize(int pageSize){ xJ2O4ob
this.pageSize = pageSize; PL9eU y
} EhIV(q9x
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publicint getTotalCount(){ leES YSY:
return totalCount; GtM(
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} ,>
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publicvoid setTotalCount(int totalCount){ xa{<R+LR
if(totalCount > 0){ :\+{;;a@
this.totalCount = totalCount; O/Y\ps3r
int count = totalCount / C?60`^
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pageSize; YF! &*6m
if(totalCount % pageSize > 0) JU'WiR
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count++; d]7|v
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indexes = newint[count]; tSb?]J
for(int i = 0; i < count; i++){ uqa4&2(I=j
indexes = pageSize * UROj9COv
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i; 8{G?92
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} t$H':l0
}else{ pdi=6<?bd
this.totalCount = 0; 6/[Z178m
} ^5;vx
} L`jB)wF/J
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publicint[] getIndexes(){ $K?T=a;z
return indexes; )pjjW"C+
} %9QMzz5
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publicvoid setIndexes(int[] indexes){ {}g %"mi#
this.indexes = indexes; Z(Eke
} \7,MZt
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publicint getStartIndex(){ my\o P(e\
return startIndex; :T7?
} H~[LJ5x
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publicvoid setStartIndex(int startIndex){ 9U|<q
if(totalCount <= 0) y8w0eq94
this.startIndex = 0; msc 1^2
elseif(startIndex >= totalCount) OB?S kR
this.startIndex = indexes kRN|TDx(
:F7k{~
[indexes.length - 1]; NV}RRs
elseif(startIndex < 0) ).NcLJw_
this.startIndex = 0; W&+y(Z-t
else{ "YG\
this.startIndex = indexes O->_/_
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[startIndex / pageSize]; ]~ !XiCqu
} *?_qE
} cc|CC
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publicint getNextIndex(){ r"{Is?yKe
int nextIndex = getStartIndex() + 6kt]`H`cfJ
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pageSize; RDs,sj/Y9?
if(nextIndex >= totalCount) Y&vHOA
return getStartIndex(); jDlA<1
else T[0V%Br{d+
return nextIndex; 8pYyG
| \
} /[a|DUoHO
n}< ir!ZTO
publicint getPreviousIndex(){ 3yTQ
int previousIndex = getStartIndex() - @72x`&|I?u
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pageSize; ycgfZ 3K
if(previousIndex < 0) L]k*QIn:h
return0; N9i}p^F<_
else 5%<TF.;-J
return previousIndex; 7$(_j<o`
} 'FShNY5
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} XVQL.A7
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抽象业务类 a(8>n
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java代码: $brKl8P
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/** <fNGhmL
* Created on 2005-7-12 r_Lu~y|
*/ luW
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package com.javaeye.common.business; h ZoC _\
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import java.io.Serializable; |/@0~O(6
import java.util.List; A)8rk_92Q
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import org.hibernate.Criteria; |vv]Z(_
import org.hibernate.HibernateException; \).Nag +
import org.hibernate.Session; za,6du6
import org.hibernate.criterion.DetachedCriteria; fC_zX}3
import org.hibernate.criterion.Projections; #hIEEkCp +
import 5pO]vBT
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org.springframework.orm.hibernate3.HibernateCallback; 5B%w]n
import GGCqtA^@7d
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org.springframework.orm.hibernate3.support.HibernateDaoS 6hZ.{8e0
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upport; ('=Z}~
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import com.javaeye.common.util.PaginationSupport; Iq+2mQi*/k
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public abstract class AbstractManager extends &a.']!$^"
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HibernateDaoSupport { +<&E3O r
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privateboolean cacheQueries = false; ;:P7}v fz!
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privateString queryCacheRegion; bn $)f6%
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publicvoid setCacheQueries(boolean 9+}cE**=d
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cacheQueries){ Qe_+r(3)k
this.cacheQueries = cacheQueries; U<Vy>gIC
} X1Qr_o-BR
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publicvoid setQueryCacheRegion(String 6_WmCtvF
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queryCacheRegion){ jDkm:X}:
this.queryCacheRegion = {t&*>ma6)
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queryCacheRegion; J<rlz5':
} :i.t)ES
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publicvoid save(finalObject entity){ 6Z Xu,ks}
getHibernateTemplate().save(entity); x.ba|:5
} hqL+_|DW
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publicvoid persist(finalObject entity){ /N>} 4Ay
getHibernateTemplate().save(entity); {#N%Bq}
} E30Ln_^o
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publicvoid update(finalObject entity){ NddO*`8+)
getHibernateTemplate().update(entity); ^}J<)}Q
} sZKEUSFD #
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publicvoid delete(finalObject entity){ [_V:)
getHibernateTemplate().delete(entity); ul$,q05nb
} 6(Vhtr2(*
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publicObject load(finalClass entity, ~T%Ui#Gc
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finalSerializable id){ Pubv$u2
return getHibernateTemplate().load q(gjT^aN
;,k=<]
(entity, id); pl|h>4af
} 9p4y>3
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publicObject get(finalClass entity, KU]ok '
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finalSerializable id){ *jE;9^
return getHibernateTemplate().get uaaf9SL?
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(entity, id); J1X~vQAe
} Z5$fE7ba+
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publicList findAll(finalClass entity){ b1xpz1
return getHibernateTemplate().find("from T cJ$[
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" + entity.getName()); <!F3s`7~
} ,5{$+
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publicList findByNamedQuery(finalString s7l23*Czl
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namedQuery){ FqZgdmwR
return getHibernateTemplate '#q4Bc1
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().findByNamedQuery(namedQuery); Zj!Abji=O
} \J3/keL
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publicList findByNamedQuery(finalString query, R%"K
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finalObject parameter){ y3JMbl[S0
return getHibernateTemplate Da_()e[9p
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().findByNamedQuery(query, parameter); MA*
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} VD[pZ2;4
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publicList findByNamedQuery(finalString query, :G=FiC
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finalObject[] parameters){ ||Y<f *
return getHibernateTemplate Q4Q pn
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().findByNamedQuery(query, parameters); R\O.e
} IZrk1fh
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publicList find(finalString query){ Y3rt5\!
return getHibernateTemplate().find E ]f)Os$
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(query); pW|u P8#
} N'?u1P4G
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publicList find(finalString query, finalObject pj8azFZ
#{PmNx%M
parameter){ +}JM&bfK
return getHibernateTemplate().find Md&WJ
};L
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(query, parameter); OfZN|S+~W
} f^b K=#
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public PaginationSupport findPageByCriteria DQ80B)<O
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(final DetachedCriteria detachedCriteria){ ^+/kr/
return findPageByCriteria {_>em*V b
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); lm0N5(XP
} :YO@_
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public PaginationSupport findPageByCriteria DL8x":;
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(final DetachedCriteria detachedCriteria, finalint 6v732;^
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startIndex){ KoBW}x9Jp
return findPageByCriteria 0. ;}]v
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(detachedCriteria, PaginationSupport.PAGESIZE, ,o#kRWRG
zP) ~a
startIndex); ~
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} D4u%6R|F
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public PaginationSupport findPageByCriteria h~}.G{"
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(final DetachedCriteria detachedCriteria, finalint {?8B,G2r
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pageSize, @cD uhK"U}
finalint startIndex){ TO#Pz.)>B6
return(PaginationSupport) .~D>5 JnEk
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getHibernateTemplate().execute(new HibernateCallback(){ I4c!m_sr
publicObject doInHibernate <L0#O(L
r4XH =
(Session session)throws HibernateException { 0L-!!
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Criteria criteria = 5iX!
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~)]} 91p
detachedCriteria.getExecutableCriteria(session); m$2<`C=
int totalCount = .*/Fucr
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((Integer) criteria.setProjection(Projections.rowCount #JW+~FU`
9pSUIl9|j
()).uniqueResult()).intValue(); Ud(`V:d
criteria.setProjection |U'I/A
svhI3"r
(null); j`>^1Q
List items = Y%aWK~O
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criteria.setFirstResult(startIndex).setMaxResults iCQ>@P]nE
8y2+$
(pageSize).list(); !{%: qQiA
PaginationSupport ps = `BXS)xj
A[N{
new PaginationSupport(items, totalCount, pageSize, j<yiNHC
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startIndex); YwDt.6(+,
return ps; gFN9jM
} r ,(Mu
}, true); L"(4R^]
} {]N3f[w
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public List findAllByCriteria(final 5Rv+zQ#GR
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DetachedCriteria detachedCriteria){ {8RFK4! V@
return(List) getHibernateTemplate B4H!5b
!nf-}ze{
().execute(new HibernateCallback(){ t+ Bf#:
publicObject doInHibernate 8?FueAM'
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(Session session)throws HibernateException { qSU|=
Criteria criteria = 2umv|]n+l|
#1nJ(-D+
detachedCriteria.getExecutableCriteria(session); 6p;m\
return criteria.list(); o*S"KX$
} X[$++p
.
}, true); >bo'Y9C
} _GYMPq\%L#
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public int getCountByCriteria(final Vm1-C<V9
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DetachedCriteria detachedCriteria){ `)$_YZq|SR
Integer count = (Integer) 0#p/A^\#7M
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getHibernateTemplate().execute(new HibernateCallback(){ Am4lEvb
publicObject doInHibernate $&I'o
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(Session session)throws HibernateException { umEVy*hc
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); L V{Q,DrP
return \3YO<E!t
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criteria.setProjection(Projections.rowCount UK[v6".^h
ts~{w;c
()).uniqueResult(); [1G^/K"
} >!6JKL~=
}, true); gXFWxT8S
return count.intValue(); cI0 ]}S
} d9^E.8p$
} 30j|D3-
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用户在web层构造查询条件detachedCriteria,和可选的 aBuoHdg;
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 S_(d9GK<
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PaginationSupport的实例ps。 (]2H7X:b
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ps.getItems()得到已分页好的结果集 <cN~jv-w$
ps.getIndexes()得到分页索引的数组 m:QG}{<.h
ps.getTotalCount()得到总结果数 B^ 7eo W
ps.getStartIndex()当前分页索引 r),PtI0X
ps.getNextIndex()下一页索引 7*+]wEs
ps.getPreviousIndex()上一页索引 >p\e0n
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _o3e]{
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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 (t^n'V
~:4kU/]
一下代码重构了。 -NGK@Yk22
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我把原本我的做法也提供出来供大家讨论吧: uYI@9U
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首先,为了实现分页查询,我封装了一个Page类: fT\:V5-
java代码: )=pD%$iq
}
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/*Created on 2005-4-14*/ . RVVWqW
package org.flyware.util.page; Yf_6PGNzX
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/** 9' 1B/{
* @author Joa E\7m<'R
* %V!iQzL1
*/ )}v3q6?_
publicclass Page { R9vT[{!i
$"JpFT
/** imply if the page has previous page */ NR%Y+8^M
privateboolean hasPrePage; }CL"S_>1
&jA\hg#9
/** imply if the page has next page */ *hhmTc#
privateboolean hasNextPage; l(W[_ D
4Aes#{R3v
/** the number of every page */ ,Dmc2D
privateint everyPage; ]:]H:U]p
+]xFoH
/** the total page number */ )P&9A)8
privateint totalPage; y8Xv~4qQW
5i6
hp;=
/** the number of current page */ >B -q@D
privateint currentPage; AIl4]F5I
\5
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/** the begin index of the records by the current Fe&qwq"
\p&~,%
query */ B1
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privateint beginIndex; qZk'tRv
hi2sec|;<
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/** The default constructor */ rnFM/GAy
public Page(){ c~,23wP1
U'( sn
} }ucIH@U{
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/** construct the page by everyPage \0;(VLN'U
* @param everyPage *O$CaAr\s
* */ f|EUqu%E
public Page(int everyPage){ 7v}x?I
this.everyPage = everyPage; ;^u*hZN[Up
} q z&+=d@
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/** The whole constructor */ bUy,5gk-
public Page(boolean hasPrePage, boolean hasNextPage, )emOKS
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int everyPage, int totalPage, * A|-KKo\
int currentPage, int beginIndex){ W`rNBfG>
this.hasPrePage = hasPrePage; #G]! %
this.hasNextPage = hasNextPage; FyL_xu\e
this.everyPage = everyPage; yoe}$f4
this.totalPage = totalPage; imL_lw^?
this.currentPage = currentPage; b;mSQ4+
this.beginIndex = beginIndex; \uOdALZ
} iTo k[uJ}
`s#Hq\C
/** m`?MV\^
* @return A~(l{g
* Returns the beginIndex. 2(!fg4#+
*/ KU9Z"9#
publicint getBeginIndex(){ Rf %HIAVE
return beginIndex; SjEAuRDvUz
} |+IZS/W"
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/** hqSJ(gs{
* @param beginIndex !/{+WHxIr|
* The beginIndex to set. Oc?+M 5
*/ &p
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publicvoid setBeginIndex(int beginIndex){ R>@uY(>dJ
this.beginIndex = beginIndex; Vn=qV3OE]
} KLQTKMNv
B@v\eF;
/** mY!iu(R1
* @return )U<Y0bZA!
* Returns the currentPage. yR~-k?7b
*/ i7[uLdQ
publicint getCurrentPage(){ `BFIC7a
return currentPage; ~:Uwg+]j
} kdx
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jA
2
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/** ZUXr!v/R:1
* @param currentPage #%3rTU
* The currentPage to set. W1aa:hEf
*/ "O>n@Q|
publicvoid setCurrentPage(int currentPage){ 1r)kR@!LNG
this.currentPage = currentPage; YA(@5CZ
} +A_J1iJ<
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/** O{z}8&oR:
* @return I 8
* Returns the everyPage. 36m5bYMd)
*/ "%2xR[NF
publicint getEveryPage(){ ~vdkFc(8B
return everyPage; W{cY6@
} Q-TV*FD.
.4.pJbOg
/** c8 K3.&P6
* @param everyPage ewsKH\#
* The everyPage to set. ]LPQYL
*/ cFd
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publicvoid setEveryPage(int everyPage){ i=FQGWAUu
this.everyPage = everyPage; `ejUs]SR
} eBN)g^
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/** bucR">_p
* @return 7Ob*Yv=[
* Returns the hasNextPage. \6|/RFT
*/ ,FQdtNMap
publicboolean getHasNextPage(){ 0IM8
return hasNextPage; v]:=K-1n
} =/Aj
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/** eKZ%2|+j!7
* @param hasNextPage Z@D*1\TG=
* The hasNextPage to set. |Yi)"-
*/ Fr?z"
publicvoid setHasNextPage(boolean hasNextPage){ `xS{0P{uj
this.hasNextPage = hasNextPage; DLPUqKL]
} ri~<~oB2:
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/** m8]?hJY3l
* @return 79J-)e9
* Returns the hasPrePage. JeH;v0
*/ ]bCq=6ZKR
publicboolean getHasPrePage(){ L7Dh(y=;7
return hasPrePage; P%pp
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} _K2?YY(#>
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/** 8am`6;O:!
* @param hasPrePage 9W*+SlH@!
* The hasPrePage to set. qf'm=efRyu
*/
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publicvoid setHasPrePage(boolean hasPrePage){ Sywu=b
this.hasPrePage = hasPrePage; vP!GJX&n5
} s3s4OAY
:
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/** fCAiLkT,C[
* @return Returns the totalPage. PrF}a<:n:
* w [>;a.$
*/ p(SRjQt
publicint getTotalPage(){ z:Sigo_z[
return totalPage; Ha>*?`?yI
} F#|O@.tDG
qKS;x@
/** |rRO@18dA
* @param totalPage JF9yVE -
* The totalPage to set. F^aR+m
*/ ~iBgw&Y
publicvoid setTotalPage(int totalPage){ = iB,["s
this.totalPage = totalPage; 9V uq,dv
} d87vl13
rf+:=|/_3
} /{2*WI;
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qr\!*\9
oj,lz?
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 MWk:sBCqr
IHfzZHy
个PageUtil,负责对Page对象进行构造: 9ch#}/7B
java代码: Gm`}(;(A
FxG7Pk+=
6~:Sgt nU
/*Created on 2005-4-14*/ aMARZ)V
package org.flyware.util.page; [36,eK
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import org.apache.commons.logging.Log; Dz=k7zRg"
import org.apache.commons.logging.LogFactory; /T^ JS
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/** v}G]X Z8
* @author Joa kU5.iK'
* !;@_VWR
*/ 8?t"C_>*e
publicclass PageUtil { lor8@Qz
3XiO@jzre
privatestaticfinal Log logger = LogFactory.getLog M_0zC1
F-(dRSDNM
(PageUtil.class); ^_I} x)i*@
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/** pZZgIw}aS
* Use the origin page to create a new page hli|B+:m"
* @param page Oh.ZPG=
* @param totalRecords *x~xWg9^
* @return 1RLY $M
*/ WlB'YL-`g
publicstatic Page createPage(Page page, int Hs"(@eDV&J
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totalRecords){ 5/[H+O1;
return createPage(page.getEveryPage(), u/b7Z`yX}
kID[#g'
page.getCurrentPage(), totalRecords); Q0?\]2eet9
} gIWrlIV{9
mAgF73,3
/** V{-AP=C7
* the basic page utils not including exception n;HHogA
r,SnXjp@
handler wCMQPt)VS
* @param everyPage +`mGK:>
* @param currentPage ymY1o$qWB}
* @param totalRecords 5OIc(YhYf
* @return page K)7zKEp`cj
*/ n>,L=wV
publicstatic Page createPage(int everyPage, int ;:S&F
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currentPage, int totalRecords){ {",MCu_V
everyPage = getEveryPage(everyPage); 2 gq$C"
currentPage = getCurrentPage(currentPage); GJi~y
int beginIndex = getBeginIndex(everyPage, 05Fz@31~
148V2H)
currentPage); ?[TfpAtQ`
int totalPage = getTotalPage(everyPage, ubMOD<
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totalRecords); $lIWd
boolean hasNextPage = hasNextPage(currentPage, idc`p?XP
_Jz8{` "
totalPage); aeyNdMk-
boolean hasPrePage = hasPrePage(currentPage); =-cwXo{Q.O
zo{/'BnU
returnnew Page(hasPrePage, hasNextPage, EqiFy"H
everyPage, totalPage, O-vGyNxP|
currentPage, sML=5=otx
p1pQU={<
beginIndex); m8Vdb"0
} Y&H}xn
2N#$X'8
privatestaticint getEveryPage(int everyPage){ -Ue$T{;RoH
return everyPage == 0 ? 10 : everyPage; )"(] Lf's
} uhH^>z
KA
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privatestaticint getCurrentPage(int currentPage){ Zv]x'3J#Y
return currentPage == 0 ? 1 : currentPage; <>xJn{f0c
} -Lu)'+
%m,6}yt
privatestaticint getBeginIndex(int everyPage, int (;x3} ]
<>eOC9;VY
currentPage){ KT|RF
return(currentPage - 1) * everyPage; mpC`Yk
} Ok5<TZ6t4k
@4d)R
privatestaticint getTotalPage(int everyPage, int i!2TH~zl
0|xIBg)
totalRecords){ p?[Tm*r
int totalPage = 0; (GnuWc\p
`J<*9dq%
if(totalRecords % everyPage == 0) %)jxW{
totalPage = totalRecords / everyPage; rVvR!"//yH
else 5hj
totalPage = totalRecords / everyPage + 1 ; VpfUm?Nq
[u@Jc,
return totalPage; z't??6
} gXT9 r' k
.xzEAu ;
privatestaticboolean hasPrePage(int currentPage){ {u{@jp
return currentPage == 1 ? false : true; @}_WE,r
} *,C(\!b
!?
7 J^rv9i4
privatestaticboolean hasNextPage(int currentPage, mvW%
w&$d* E
int totalPage){ #&<)! YY5
return currentPage == totalPage || totalPage == \]Kh[z0"
3uU]kD^
0 ? false : true; mC&=X6Q]
} e+v({^k
eg<bi@C1|
\}6;Kf}\
} 3<=,1 cU
spU)]4P&
0tISXu-
d\MLOXnLq;
`
8W*
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。 lPH%Do>K
2Y}?P+:%>
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 .Xm(D>>k
~AYN
做法如下: Y^Nuz/
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Y3kA?p0
dca;'$
的信息,和一个结果集List: ]A
FI\$qB\
java代码: ELrsx{p:
rn DCqv!'P
?oZR.D|SZ
/*Created on 2005-6-13*/ qbrp P(.
package com.adt.bo; WPZ?*Sx
4p;aS$Q
import java.util.List; 4v
p
~/NKw:
import org.flyware.util.page.Page; ZZQG?("S'
YDC mI@
/** hLJM%on
* @author Joa _AV1WS;^^8
*/ 4?N8R$
publicclass Result { }'r[m5T
!-s!f&_
private Page page; ,1'4o3
8u[-'pV!
private List content; i'stw6*J
,F&g5'
/** tg^sCxz9]
* The default constructor RMO,ZVq
*/ ]# t6Jwk
public Result(){ gVeEdo`$<
super(); xI,2LGO
} 'c\iK=fl
I%|>2}-_U
/** Li*eGlId
* The constructor using fields bo.(zAz
* HM>lg`S
* @param page u66XN^
* @param content Z*G(5SqUh"
*/ W\1i,ew>
public Result(Page page, List content){ f%5zBYCgC
this.page = page; XC{eX&,2x
this.content = content; \~P=U;l=pO
} B?VhIP e
sNun+xsf^
/** Qf@I)4'
* @return Returns the content. u3Gjg{-N7
*/ $R<Me
publicList getContent(){ m*e{\)rd#
return content; zy*/T>{#
} -}K<ni6
9&<x17'
/** B|o2K}%f
* @return Returns the page. BL@:!t
*/ T843":
public Page getPage(){ 6TP7b|
return page; ~>9_(L
} q2HYiH^L
4k./(f2+
/** RN=` -*E1
* @param content 8* Jw0mSw
* The content to set. 8H[:>;SI
*/ S/;bU:
public void setContent(List content){ R_=6GZH$G
this.content = content; q7u'_R,;
} UMX@7a,[3
.`?@%{
/** IK*07h/!
* @param page vn/.}GkpU
* The page to set. H@]MXP[_
*/ mf'V)
publicvoid setPage(Page page){ /VG2.:
this.page = page; ~
T>U
} phO;c;y}
} E*i#?u
_X?^Cy
ctcS:<r/3@
V|\7')Qq
qZ@s#UiB
2. 编写业务逻辑接口,并实现它(UserManager, w3jO6*_ M
vq34/c^
UserManagerImpl) =B.F;40
java代码: j65<8svl
I%urz!CNE*
U*.0XNKp{
/*Created on 2005-7-15*/
}-~l!
package com.adt.service; s&'QN=A
\W1/p`
import net.sf.hibernate.HibernateException; [9:9Ql_h
a&vY!vx3
import org.flyware.util.page.Page; 4tY ss
W`^@)|9^)
import com.adt.bo.Result; G@j0rnn>B
hlt[\LP=$
/** n_'{^6*O
* @author Joa S6fb f>[
*/ Uix6GT;
publicinterface UserManager { Z0l+1iMx
K_&4D'
public Result listUser(Page page)throws QY= = GfHt
Y3Q9=u*5
HibernateException; 4j)tfhwd8
aMTu-hA
} qx%}knB
(Cqn6dWK
:%IoM E
6-O_\Cq8
bJs9X/E
java代码: @B}aN@!/
4[N^>qt =
y!xE<S&Y
/*Created on 2005-7-15*/ W^"AU;^V56
package com.adt.service.impl; JchSMc.9
0wS+++n$5
import java.util.List; Y".RPiTL
* RtgC/
import net.sf.hibernate.HibernateException; *?MGMhE
fDLG>rXPT
import org.flyware.util.page.Page; =FD;~
import org.flyware.util.page.PageUtil; B5$kHM%p
itMg|%B%
import com.adt.bo.Result; D_Bb?o5
import com.adt.dao.UserDAO; g:EVhuK
import com.adt.exception.ObjectNotFoundException; 1@$Ko5
import com.adt.service.UserManager; fDSv?crv
0]4(:(B
/** bJD;>"*
* @author Joa
ge8/``=
*/ 63A}TBC
publicclass UserManagerImpl implements UserManager { }u1O#L}F5
MHa#?Q9
private UserDAO userDAO; *z7dl5xJ
)+fh-Ui
/** t%8d-+$
* @param userDAO The userDAO to set. jVq(?Gc
*/ l}qE 46EL
publicvoid setUserDAO(UserDAO userDAO){ ^b
%0B
this.userDAO = userDAO; /7
Cn(s5 o
} H*r>Y
{26ONa#i
/* (non-Javadoc) bcupo:N
* @see com.adt.service.UserManager#listUser n93=8;&
9YBv|A
(org.flyware.util.page.Page) fDP$ sW
*/ nl9P,
d
public Result listUser(Page page)throws ,UuH}E
b6*!ACY
HibernateException, ObjectNotFoundException { ]~Z6;
int totalRecords = userDAO.getUserCount(); 0#MqD[U(
if(totalRecords == 0) //aF5:Y#
throw new ObjectNotFoundException Gw1@KKg
:Lz\yARpk
("userNotExist"); F;>!&[h}G
page = PageUtil.createPage(page, totalRecords); \nP>:5E1
List users = userDAO.getUserByPage(page); D$x_o!JT
returnnew Result(page, users); (IPY^>h
} vI@%Fg+D
|n] d34E
} FJd]D[h
qcT'nZ:
,#8e_3Z$
n..g~$k
e$pMsw'MJ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 BX yo
Y5j]Z^^v
询,接下来编写UserDAO的代码: xL" |)A =
3. UserDAO 和 UserDAOImpl: I&YSQK:b
java代码: :GJ &_YHf
&
j+oJasI
b3VS\[p
/*Created on 2005-7-15*/ -!
K-Htb-
package com.adt.dao; /S lYm-uQ+
1PatH[T[
import java.util.List; {,L+1h
jkvgoxY
import org.flyware.util.page.Page; tzh1s
i
nb>7UN.9
import net.sf.hibernate.HibernateException; ivz{L-
-(b kr+N
/** <Z/x,-^*<
* @author Joa 42qYg(tZ
*/ 'R:"5d
publicinterface UserDAO extends BaseDAO { NG6& :4!
.AU)*7Gh
publicList getUserByName(String name)throws ',S'.U
JGQj w(Xs
HibernateException; *H|M;G
`F>O; >i''
publicint getUserCount()throws HibernateException; _hk.2FV:3m
)=etG
publicList getUserByPage(Page page)throws 6w@ Ii;
Y(d$
HibernateException; $O5UyKI
&kpwo )
} STaA]i}P
J:\|Nc?
[r[=W!
0xXC^jx:
;I!MLI
java代码: jXMyPNTK
xagBORg+Bd
>HS W]"k
/*Created on 2005-7-15*/ Zp#v Hs
package com.adt.dao.impl; XSZ k%_
pLzk
import java.util.List; }_68j8`
~Onoe $A[<
import org.flyware.util.page.Page; z'EajBB\f
v@d
import net.sf.hibernate.HibernateException; :EA\)@^$R
import net.sf.hibernate.Query; "l*`>5Nn9
*v3]}g[<
import com.adt.dao.UserDAO; ` 5C~
+o51x'Ld*
/** O7 $hYk
* @author Joa ~7Tc$
"I
*/ =pC3~-;3
public class UserDAOImpl extends BaseDAOHibernateImpl x
a06i#
(#E.`e1#6
implements UserDAO { smDw<slC
E}tqQ*u
/* (non-Javadoc) '>rw(3
* @see com.adt.dao.UserDAO#getUserByName : 7`[$<~E
[E
] E
(java.lang.String) JC3m.)/
*/ >L
0_ dvr
publicList getUserByName(String name)throws _}En/V_
A`}rqhU.{-
HibernateException { ^:Gie
String querySentence = "FROM user in class n= u&uqA*
&sL&\+=<(
com.adt.po.User WHERE user.name=:name"; ?28N ^
Query query = getSession().createQuery r|qp3x
JQ@E>o7_
(querySentence); [Yc G(^^
query.setParameter("name", name); McQe1
return query.list(); 1cD! :[
} u9EgdpD
oczN5YSt
/* (non-Javadoc) `6xkf&Kt
* @see com.adt.dao.UserDAO#getUserCount() lh;:M-b9
*/ >M/V oV
publicint getUserCount()throws HibernateException { ixT:)|'i
int count = 0; )}?#
String querySentence = "SELECT count(*) FROM A?pbWt~}
g #6E|n
user in class com.adt.po.User"; &mtJRfnu
Query query = getSession().createQuery HI11Jl}{
=^5Alba/
(querySentence); KW^7H
count = ((Integer)query.iterate().next y;o^- O
Bjz Pz
()).intValue(); .ODR ]7{
return count; q*7VqB
} 5w@4:$=I
c>)Yt^q&K
/* (non-Javadoc) d >t<_}
* @see com.adt.dao.UserDAO#getUserByPage I]EbodAyZ,
AQ[GO6$,%H
(org.flyware.util.page.Page) C
.~+*"Vw
*/ ^i}
L-QR
publicList getUserByPage(Page page)throws yLQ*"sw\
x-?Sn' m
HibernateException { Cy=Hy@C
String querySentence = "FROM user in class rMhB9zB1
_`:1M2=
com.adt.po.User"; csW43&
Query query = getSession().createQuery L=sYLC6d
Nu?-0>
(querySentence); AGYc |;
query.setFirstResult(page.getBeginIndex()) 7*Ej. HK
.setMaxResults(page.getEveryPage()); j+,d^!
return query.list(); @-!}BUs?
} aN8|J?JH
DuHu\>f<S
} %YC_Se7
1BpiV-]=
[CXrSST")E
?3.b{Cq{-
j?x>_#tIY
至此,一个完整的分页程序完成。前台的只需要调用 +yD`3`
E
?}U(3
userManager.listUser(page)即可得到一个Page对象和结果集对象 "\o+v|;
-RvQB
的综合体,而传入的参数page对象则可以由前台传入,如果用 cLsV`@J(k
@8ppEFw
webwork,甚至可以直接在配置文件中指定。 m1Mt#@,$
1R1z
下面给出一个webwork调用示例: n' q4
java代码: S9~+c
&b%zQ4%d-`
PC-"gi=h
/*Created on 2005-6-17*/ /*X2c6<d
package com.adt.action.user; I
,z3xU
`yH<E+
import java.util.List; tAv@R&W,
t~#zMUfac
import org.apache.commons.logging.Log; mSb#Nn6W
import org.apache.commons.logging.LogFactory; Ke2ccN
import org.flyware.util.page.Page; [VsKa\9u
0,89H4
import com.adt.bo.Result; V#S9H!hm$
import com.adt.service.UserService; \(^nSy&N
import com.opensymphony.xwork.Action; 5a|w+HO,
z;|A(*Y
/** rFj-kojg
* @author Joa vPTM
*/ |w<H!lGe!$
publicclass ListUser implementsAction{ 2;DuHO1
~^r29'3
privatestaticfinal Log logger = LogFactory.getLog =06gj)8
iA' lon
(ListUser.class); J:V6
)\J+Kiy)
private UserService userService; 1Y7Eajt-5
%R}.#,Suo
private Page page; JSCZ{vJ$
P;qN(2L/=<
privateList users; q#,f 4P
7G}2,ueI
/* Y6zbo
* (non-Javadoc) I J(
* 8{^WY7.'
* @see com.opensymphony.xwork.Action#execute() %)/P^9I6
*/ ;kS&A(
publicString execute()throwsException{ ~&7MkkftM
Result result = userService.listUser(page); 06c>$1-?
page = result.getPage(); OHb[qX\
users = result.getContent(); pgQV /6
return SUCCESS; 4GY[7^
} o4K ~
]<cK";
/** WSp
* @return Returns the page. O$&mFL[`
*/ ,}ECF>
public Page getPage(){ &3J_^210
return page; i*Sqd a
$
} 7 /VK##z
b`~p.c%(
/** 7!EBH(,z
* @return Returns the users. )ttUWy$w
*/ ,+meT`'vn
publicList getUsers(){ 7Z\--=;|[:
return users; -- %N8L;e
} 7BK0}sxO
jY%na
HaI
/** K1\a#w
* @param page @Z\,q's
* The page to set. ][9%Kl*%@p
*/ DRp~jW(\y
publicvoid setPage(Page page){ 1DE<rKI
this.page = page; 2.l Z:VLN
} ^Eb.:}!D6
$o0iLFIX/
/** J;{N72
* @param users Ay5i+)MD
* The users to set. :y%/u%L
*/ *n 6s.$p)%
publicvoid setUsers(List users){ !Wy6/F@Z
this.users = users; |:xYE{*)H
} $JJrSwR<h
$Q96,rb}k;
/** t<z`N-5*
* @param userService c#Sa]n
* The userService to set. q_g+Jf
P-D
*/ )4gJd?
8R
publicvoid setUserService(UserService userService){ 6@{(;~r
this.userService = userService; VEqS;~[
} }L+L"l&
} A+"ia1p,}
bm?sbE
g*e
7hlO#PYZ
Jq&uF*!
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, i|w81p^o
9F)z4
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 J'SZ
4'g;TI^
么只需要: -0$55pa/@:
java代码: >VP=MbN
^;Y|3)vvB
E*V`":efS
<?xml version="1.0"?> s.N7qO^:E
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K1r#8Q!t
8S mCpg
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Y^8C)p9r
K?B{rE Lp
1.0.dtd"> b\vKJ2
)vjh~ybZ
<xwork> hyCh9YOu)
]h* c,.
<package name="user" extends="webwork- ]>LhkA@V
4)h]MOZ
interceptors"> )Dw,q~xgg0
8\^}~s$$A
<!-- The default interceptor stack name V5sg#|&
FT#8L
--> u37'~&o{U
<default-interceptor-ref s+,OxRVw(
Zhh2v>QOy
name="myDefaultWebStack"/> 8/i!' 0r\
h]+C.Eqnt#
<action name="listUser" ,SynnE68
iYORu3
class="com.adt.action.user.ListUser"> Tl$[4heE
<param E^ P,*s
q|o}+Vr
name="page.everyPage">10</param> DoJ\ q+
<result J&[@}$N
,0*&OXt
name="success">/user/user_list.jsp</result> t2F_uCr
</action> k2c}3 MeP
6x h:/j3
</package> xy5lE+E_U
,&jhlZ i
</xwork> a`&f
{ /K.3
WN{ 9
cik!GA
"!Uqcay-
x(hE3S#+
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 '(f&P=[b
<3xyjX'NE
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 x_|UPF
4}_j`d/8|
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 uw[<5
!>{G,\^=pT
Mn9dqq~a
"uuVy$6C
so"$m
我写的一个用于分页的类,用了泛型了,hoho Izhee%c
,sA[)wP {
java代码: G;v8$)Zj
#33fGmd[
jhXkSj
package com.intokr.util; Q<h-FW8z
yaah*1ip[
import java.util.List; 9K5pwC\$%
),U X4%K=
/** Gb8D[1=u=
* 用于分页的类<br> ,4zmb`dP<
* 可以用于传递查询的结果也可以用于传送查询的参数<br> c_-drS
* 8TGOx%}i
* @version 0.01 DF1I[b=]
* @author cheng NLUT#!Gr
*/ zm]aU`j
public class Paginator<E> { ]w;rfn9D
privateint count = 0; // 总记录数 -~v|Rt
privateint p = 1; // 页编号 uJFdbBDSh
privateint num = 20; // 每页的记录数 fBRo_CU8!
privateList<E> results = null; // 结果 4]h
=yc R
$
et0s;GBv
/** J)`-+}7$v
* 结果总数 f|h|q_<;
*/ :n0vQ5a
publicint getCount(){ h\5OrD@L
return count; k5D%y3|9
} (@%gS[]
V.O(S\
publicvoid setCount(int count){ xl6,s>ob
this.count = count; giZP.C"0
} +Vm}E0Ov
2q3+0Et8
/** )Y2{_ bx4"
* 本结果所在的页码,从1开始 Gnfd;.
(.
* 4US"hexE<
* @return Returns the pageNo. #0ETY\}ZD
*/ S{;sUGcu
publicint getP(){ Pl=ZRKn
return p; R%Q@
} b~'"^ Bts*
V,q](bg
/** Pa{%\dsv
* if(p<=0) p=1 BFL`!^
* uT}' Y)m
* @param p 5]n[]FW
*/ V}dJ.I /#
publicvoid setP(int p){ FrTi+& <
if(p <= 0) AWP"b?^G|
p = 1; ]|MEx{BG-
this.p = p; .Xce9C0SW
} ( M7pT
p 3 w
/** q:dHC,fO
* 每页记录数量 ;.TRWn#
*/ Q$HG
publicint getNum(){ &;D8]7d
return num; I_<I&{N>
} >sWp?
g=QDu7Ux
/** /lo2y?CS*
* if(num<1) num=1 k9L?+PD
*/ D@Vt^_
publicvoid setNum(int num){ OY:,D
if(num < 1) Zn
''_fjh
num = 1; 5[A@gw0u
this.num = num; ~ vJ,`?
} \De{9v
c- }X_)U }
/** c17_2 @N
* 获得总页数 _tBTE%sO
*/ S<4c
r
publicint getPageNum(){
/% M/
return(count - 1) / num + 1; KO]T<R
h<
} eu(:`uu
+tVaBhd!
/** So0f)`A
* 获得本页的开始编号,为 (p-1)*num+1 kdl:Wt*4o
*/ SzjkI+-$:
publicint getStart(){ p4'G$]#
return(p - 1) * num + 1; @7?#Y|`
} DpUbzr41+k
#7MUJY+
9
/** KTP8?Q"n0
* @return Returns the results. "J4WzA%i
*/ Ed_N[I
publicList<E> getResults(){ hnDBFQ{
return results; [/Rf\T(,jn
} -F<Wd/Xse
](&{:>RNJ
public void setResults(List<E> results){ O+]Ifm [
this.results = results; |h;0H`
} Kac' ;1
rNB_W.
public String toString(){ B oC5E#;G
StringBuilder buff = new StringBuilder !"\80LP
J[4mLU
(); i70wrW#k
buff.append("{"); ]=>F.GE
buff.append("count:").append(count); .
koYHq
buff.append(",p:").append(p); \'|>p/5I
buff.append(",nump:").append(num); mGJasn
buff.append(",results:").append 3?1`D/
;i<|9{;
(results); tE)suU5Y
buff.append("}"); prTw'~(B
return buff.toString(); FLGk?.x$\
} fpFhn
R)mu2^
} [uI|DUlI6o
Bh;7C@dq
@JyK|.b#0