Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {/SLDyf%Z
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Kq2,J&Ca3
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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 JO"-"&>
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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 fr([g?F%D
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。
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分页支持类: IJV1=/NJW
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java代码: lq\/E`fc`
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package com.javaeye.common.util; D\i8WU
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import java.util.List; Id;YIycXe
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publicclass PaginationSupport { ?:XbZ"25pJ
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publicfinalstaticint PAGESIZE = 30; l9Sx'<
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privateint pageSize = PAGESIZE; *FrlzIAom
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privateList items; 6`Af2Y_
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privateint totalCount; DKxzk~sOM
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privateint[] indexes = newint[0]; ts3BmfR?
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privateint startIndex = 0; yYM_
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public PaginationSupport(List items, int 'CSIC8M<j
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totalCount){ O4i5fVy{
setPageSize(PAGESIZE); [exIK
setTotalCount(totalCount); z}:|is)?
setItems(items); 1rmK#ld"=Z
setStartIndex(0); vkQkU,q
} c3$h-M(jVJ
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public PaginationSupport(List items, int t^zmvPDK
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totalCount, int startIndex){ $Q cr
setPageSize(PAGESIZE); HKZD*E((
setTotalCount(totalCount); 7$&3(#!N
setItems(items); N?mTAF'M
setStartIndex(startIndex); o<r|YRzQl
} kxp, ZP
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public PaginationSupport(List items, int N-4k
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* vMNv
totalCount, int pageSize, int startIndex){ 6(uK5eD(!n
setPageSize(pageSize); ( d2|r)O
setTotalCount(totalCount); RiX~YLeM
setItems(items); u79,+H@ep
setStartIndex(startIndex); ZfYva(zP{Q
} ^ A`@g4!
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publicList getItems(){ SuU_psF
return items; zrg#BXj7
} _b8?_Zq
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publicvoid setItems(List items){ M{ mdh\
this.items = items; QXcSDJ
} Gcseq
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publicint getPageSize(){ 5}uH;E)4
return pageSize; MWxv\o
} Mr3;B+S
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publicvoid setPageSize(int pageSize){ }bxW@(bs
this.pageSize = pageSize; 8;C_@
} L-T3{I,3
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publicint getTotalCount(){ "
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return totalCount; )d\u_m W^
} q{?ku!cL
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publicvoid setTotalCount(int totalCount){ ?!:$Z4G
if(totalCount > 0){ '9Hah
this.totalCount = totalCount; IP]"D"
int count = totalCount / 8 N5ga
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pageSize; ^gK8
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if(totalCount % pageSize > 0) Wp[R$/uT
count++; &Q85B q
indexes = newint[count]; eKq`t.*Ft
for(int i = 0; i < count; i++){ _ xAL0 (
indexes = pageSize * `T
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i; ;%j1'VI
} f;u<r? >Z
}else{ Gqz<;y
this.totalCount = 0; ;gC.fpu
} #=G[~m\
} q-g3!
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publicint[] getIndexes(){ Sj$XRkbj:
return indexes; Uo!#p'<w)p
} H |1owmbD
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publicvoid setIndexes(int[] indexes){ 5gPcsn"D
this.indexes = indexes; $&@L[[xl
} 19u'{/Y"
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publicint getStartIndex(){ =X0"!y"
return startIndex; Ez*9*]O*+
} /WlpRf%
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publicvoid setStartIndex(int startIndex){ vT#$`M<
if(totalCount <= 0) {p{TG5rwX
this.startIndex = 0; G8y:f%I!b
elseif(startIndex >= totalCount) YR2Q6}xR
this.startIndex = indexes J 5Nz<
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[indexes.length - 1]; 0jlwL
elseif(startIndex < 0) {g:I5
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this.startIndex = 0; ndIf1}
else{ 3 9|4)1e
this.startIndex = indexes -\b$5oa(
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[startIndex / pageSize]; &:i|;^^2
} "gcHcboU5$
} S+mZ.aFS0z
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publicint getNextIndex(){ _k0X)N+li
int nextIndex = getStartIndex() + q"|,HpQ
t4a/\{/#9|
pageSize; #+vIq?
if(nextIndex >= totalCount) RJo"yB$1e6
return getStartIndex(); ~VRt6C
else j{i3lGaN
return nextIndex; 7gL N7_2
} :
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publicint getPreviousIndex(){ T+O Qa+E@P
int previousIndex = getStartIndex() - \,-t]$9
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pageSize; *?zyF@K{%
if(previousIndex < 0) %6\e_y%
return0; BI'}
else `uO(#au,U
return previousIndex; Ag3[Nu1
} ,X[lC\1a
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} 5AvbKT
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抽象业务类 p7UdZOi2
java代码: 03F%!Rm/j
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/** :u%Jrc(W
* Created on 2005-7-12 td:GZ %
*/ kEH(\3,l
package com.javaeye.common.business; h|=<I)}z
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import java.io.Serializable; e/pZLj]M
import java.util.List; tevB2'3^
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import org.hibernate.Criteria; EJM6TI"
import org.hibernate.HibernateException; gWxpGW^eZ~
import org.hibernate.Session; MZyzc{c,
import org.hibernate.criterion.DetachedCriteria; ,t`u3ykh
import org.hibernate.criterion.Projections; 5'JONw'\
import Qi
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org.springframework.orm.hibernate3.HibernateCallback; }@kD&2
import |i)7jG<
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org.springframework.orm.hibernate3.support.HibernateDaoS h]wahExYP
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upport; {XT3M{`rWL
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import com.javaeye.common.util.PaginationSupport; -^C't_Q o
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public abstract class AbstractManager extends ^BDM'
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HibernateDaoSupport { N7S?m@
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privateboolean cacheQueries = false; V/X4WZs|i
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privateString queryCacheRegion; gnW]5#c@
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publicvoid setCacheQueries(boolean 8VbHZ9Q
AS 5\X.%L*
cacheQueries){ _|VWf 8?\
this.cacheQueries = cacheQueries; *Y4h26
} svt%UE|_:$
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publicvoid setQueryCacheRegion(String E5-f{Qc
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queryCacheRegion){ vx:MLmZ.
this.queryCacheRegion = 'z'q)vcr
$$UMc-Pq
queryCacheRegion; Who7{|M\'
} \E9Hk{V:6
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publicvoid save(finalObject entity){ XCQS_'D
getHibernateTemplate().save(entity); U>0' K3_
} 80PlbUBb!
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publicvoid persist(finalObject entity){ c$X0C&m
getHibernateTemplate().save(entity); BXNt@%
} >d.o1<
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publicvoid update(finalObject entity){ W<J".2D
getHibernateTemplate().update(entity); aBo8?VV]8
} ]_cBd)3P}
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publicvoid delete(finalObject entity){ Ix+===6
getHibernateTemplate().delete(entity); Y^zL}@
} G k'j<a
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publicObject load(finalClass entity, 7@[3]c<=
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finalSerializable id){ 4nC`DJ;V
return getHibernateTemplate().load KfC8~{O-
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(entity, id); a&>Tk%
} q3+G
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publicObject get(finalClass entity, 3j{VpacZY
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finalSerializable id){ #[.vfG
return getHibernateTemplate().get 'qGKS:8
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(entity, id); )&G
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} v3b[08
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publicList findAll(finalClass entity){ 5O.dRp7dJ
return getHibernateTemplate().find("from $=>(7 =l_
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" + entity.getName()); B7:8%r/
} *gu4%
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publicList findByNamedQuery(finalString j@4
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namedQuery){ Ri$wt.b
return getHibernateTemplate Qo*,2B9R L
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().findByNamedQuery(namedQuery); sE*A,z?
} 6S-1Wc4
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publicList findByNamedQuery(finalString query, T6s~f$G
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finalObject parameter){ F_8nxQ-
return getHibernateTemplate .#"O VI]#
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().findByNamedQuery(query, parameter); X[L6Av
} ISHNeO8
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ O34'c_ fZ
return getHibernateTemplate AJ'YkSg
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().findByNamedQuery(query, parameters); l3Vw?f
} 8 *@knkJ
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publicList find(finalString query){ zWiMl.[
return getHibernateTemplate().find *9"L?S(X#
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(query); ;p~ &G"-C`
} nSH
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publicList find(finalString query, finalObject #"}Z'|X*
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parameter){ yZf+*j/a7
return getHibernateTemplate().find (<ybst6+I
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(query, parameter); az7<@vSXi
} /0(2PVf
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public PaginationSupport findPageByCriteria jEQr{X7bEL
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(final DetachedCriteria detachedCriteria){ N2yxli
return findPageByCriteria )|>LSKTEl
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); v:s.V>{"S
} QcyYTg4i
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public PaginationSupport findPageByCriteria xNG'UbU
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(final DetachedCriteria detachedCriteria, finalint WNkAI9B
qzv$E;zAl
startIndex){ g%z?O[CN
return findPageByCriteria r>+Hwj0>
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(detachedCriteria, PaginationSupport.PAGESIZE, vF, !8e'v
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startIndex); n7~!klF-
} 0mB]*<x8
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public PaginationSupport findPageByCriteria &gc8"B@V
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v,
(final DetachedCriteria detachedCriteria, finalint VFN\
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pageSize, @";z?xj
finalint startIndex){ uHdrHP
return(PaginationSupport) 4;;F(yk8
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getHibernateTemplate().execute(new HibernateCallback(){ XcJ'w
publicObject doInHibernate O@U[S.IK
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(Session session)throws HibernateException { J~z;sTR
Criteria criteria = 7)zn[4v7qt
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detachedCriteria.getExecutableCriteria(session); \m!swYy
int totalCount = y}jX/Ln
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((Integer) criteria.setProjection(Projections.rowCount M 7j0&>NTG
x;NCW
()).uniqueResult()).intValue(); KK-9[S-
criteria.setProjection Dx/!^L02
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(null); =~YmM<L
List items = 3=9yR**
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criteria.setFirstResult(startIndex).setMaxResults O~F/pJN`
;u LD_1%
(pageSize).list(); 'tK5s>gv<
PaginationSupport ps = se](hu~w
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new PaginationSupport(items, totalCount, pageSize, iqCKVo7:M
hx$-d}W{
startIndex); Qg+0(odd
return ps; )%8oE3O#
} VXvr`U\
}, true); ;i`X&[y;
} !pI)i*V|
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public List findAllByCriteria(final =LJc8@<:f
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DetachedCriteria detachedCriteria){ d>:(>@wz
return(List) getHibernateTemplate &F"Mkyf
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().execute(new HibernateCallback(){ r@+IDW.=9
publicObject doInHibernate uAT01ZEm
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(Session session)throws HibernateException { jh.W$.Oq
Criteria criteria = [X:mmM0gd
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detachedCriteria.getExecutableCriteria(session); R}4o{l6
return criteria.list(); pYV$sDlD
} q4vu r>m6
}, true); 10dVV[=
} +F ~;Q$T
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public int getCountByCriteria(final lpkg(J#&
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DetachedCriteria detachedCriteria){ dwks"5l
Integer count = (Integer) ~I6Er6$C^
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getHibernateTemplate().execute(new HibernateCallback(){ NUBzm nA>8
publicObject doInHibernate 0`/ PEK{
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(Session session)throws HibernateException { ABEC{3fWpu
Criteria criteria = ITh1|yP
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detachedCriteria.getExecutableCriteria(session); z<rdxn,9
return pmXx2T#=
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criteria.setProjection(Projections.rowCount H n+1I
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()).uniqueResult(); YMP:T?vMVh
} )NZ6!3[@
}, true); %>'2E!%
return count.intValue(); /h%<e
} !o &+
} k%#`{#ni
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用户在web层构造查询条件detachedCriteria,和可选的 iC&=-$vu
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 .z+?b8Q\
1&c>v3 $2
PaginationSupport的实例ps。 zLXmjrC
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ps.getItems()得到已分页好的结果集 CFqoD l
ps.getIndexes()得到分页索引的数组 -yeQQ4b
ps.getTotalCount()得到总结果数 0m,A`*o
ps.getStartIndex()当前分页索引 TCp!4-~,
ps.getNextIndex()下一页索引 49}yw3-
ps.getPreviousIndex()上一页索引 "s2?cQv{#
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (6z^m?t?
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 hC<X\yxe
'P}"ZHW
一下代码重构了。 +V1EqC*
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我把原本我的做法也提供出来供大家讨论吧: n1o/-UY
qAm$yfYs`
首先,为了实现分页查询,我封装了一个Page类: k(o[T),_%0
java代码: )gV+BHK
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/*Created on 2005-4-14*/ OYC4iI
package org.flyware.util.page; -2|D(
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/** dra'1E
* @author Joa ];6c/#2x
* 0t5>'GYX
*/ `3kE$h#
publicclass Page { QRdNi1&M
$ZYEH
/** imply if the page has previous page */ %0INtq
privateboolean hasPrePage; 0m)["g4
KM4w{
/** imply if the page has next page */ hxx,E>k
privateboolean hasNextPage; _`/0/69
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/** the number of every page */ p+;Re2Uyg
privateint everyPage; L@S"c
(
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/** the total page number */ 93x.b]]"
privateint totalPage; [{N
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/** the number of current page */
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privateint currentPage; twt
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/** the begin index of the records by the current \l{*1lQ`
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query */ PTA;a0A
privateint beginIndex; n)} J<
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/** The default constructor */ CSc*UX+
public Page(){ _@;2h`q ?
<?52Svi}}
} -QIcBzw;q
cZ|D!1%
/** construct the page by everyPage JwB:NqB
* @param everyPage s6Bt)8A
* */ Yc=y Vh
public Page(int everyPage){ |_F-Abk
this.everyPage = everyPage; ,TOLr%+v~n
} )
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/** The whole constructor */ %2BFbaE
public Page(boolean hasPrePage, boolean hasNextPage, yZK1bnYG|I
@<CJbFgJp
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int everyPage, int totalPage, #1hT#YN
int currentPage, int beginIndex){ ,9|%
this.hasPrePage = hasPrePage; :m5&
i&
this.hasNextPage = hasNextPage; )oTEB#J
this.everyPage = everyPage; 'e3y|
this.totalPage = totalPage; u>&\@?(
this.currentPage = currentPage; 8)5n
this.beginIndex = beginIndex; 34YYw@?}Y
} Mn>dI@/gM
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/** z"}k\B-5
* @return jm RYL("
* Returns the beginIndex. X]cB`?vR
*/ Lj *FKP\{
publicint getBeginIndex(){ ol!o8M%Q
return beginIndex; KblOP{I
} kjaz{&P
J}jK_
/** Vnh
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* @param beginIndex 3mWo`l
* The beginIndex to set. rctn0*MP
*/ lx$Y-Tb^F
publicvoid setBeginIndex(int beginIndex){ \^Y#"zXo1
this.beginIndex = beginIndex; XYod>[.x
} l]WV?^*
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/** (N;Jw^C@
* @return (&x~pv"+
* Returns the currentPage. ?[RG8,B
*/ vR,HCI
publicint getCurrentPage(){ QIi*'21a+
return currentPage; pC8(>gV<h
} enG6T
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/** U%oI*
* @param currentPage N#7 ]xL
* The currentPage to set. 3
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*/ [ R~+p#l+Q
publicvoid setCurrentPage(int currentPage){ 4bAgbx-^
this.currentPage = currentPage; ,;/4E
} EyBdL
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/** )V@qH]
* @return }S#.Pw%
* Returns the everyPage. ljiq +tT
*/ !ox &`
publicint getEveryPage(){ bx6@FKns}
return everyPage; 7[D0n7B@
} C{!Czz.N
ykM#EyN
/** `b\4h/~
* @param everyPage _
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* The everyPage to set. So`xd
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*/ @b>]q$)(}
publicvoid setEveryPage(int everyPage){ <ht>>
this.everyPage = everyPage; Phb<##OB
} T&R`s+7
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/** 2~ 'Q#(
* @return #m$H'O[WG\
* Returns the hasNextPage. xje{kx#
*/ yLDHJ}R
publicboolean getHasNextPage(){ !?l 23(d
return hasNextPage; ;euWpE;E\#
} nn=JM7e\9
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/** =x7ODBYW^
* @param hasNextPage Ev^Xs6 }"
* The hasNextPage to set. [w{ZP4d>
*/ whLske-
publicvoid setHasNextPage(boolean hasNextPage){ R
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this.hasNextPage = hasNextPage; 4k#B5^iJ
} "Y%\qw/wq
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/** xDQ$Ui.
* @return 2f:'~ P56
* Returns the hasPrePage. ItRGq
*/ 'R'>`?Nh
publicboolean getHasPrePage(){ 4U6{E#
return hasPrePage; RtIc:ym
} 9723f1&Vd
/ZzlC#`
/** %kc g#p+tE
* @param hasPrePage RU{}qPs?
* The hasPrePage to set. 1B1d>V$*
*/ #-@{ rgH
publicvoid setHasPrePage(boolean hasPrePage){ JfVayI=
this.hasPrePage = hasPrePage; yr=r?h}
} VKs\b-1
"|Pl(HX
/** /C(L(X
* @return Returns the totalPage. xJ"KR:CD>
* {[s<\<~B*
*/ sW]n~kTt'
publicint getTotalPage(){ N!m%~},s//
return totalPage; V`H#|8\i
} {$EXI]f
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/** G`
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* @param totalPage r]E$uq
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* The totalPage to set. c3}}cFe
*/ w1}[lq@
publicvoid setTotalPage(int totalPage){ )R|7> 97
this.totalPage = totalPage; a>kDG <.A
} i]YQq! B
n -=\n6"P
} zJsoenU
/F4:1
}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 :J~j*_hZ
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个PageUtil,负责对Page对象进行构造: (]V.#JM
java代码: {c1qC zM4
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/*Created on 2005-4-14*/ p']AXJ`Z
package org.flyware.util.page; ]S:@=9JB'
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import org.apache.commons.logging.Log; J{Ay(
import org.apache.commons.logging.LogFactory; Cn55%:
[x)e6p)
/** OMZT\$9yT
* @author Joa 4tC_W!?$t
* g}D$`Nx:
*/ K@i*Nl
publicclass PageUtil { 0l##M06>
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privatestaticfinal Log logger = LogFactory.getLog Lg?'1dg
'
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(PageUtil.class); Jt)~h,68
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/** Y/^<t'o&
* Use the origin page to create a new page n>4S P_[E7
* @param page S?{5DxilO
* @param totalRecords ep?0@5D}]
* @return xHGoCFB
*/ 3dbf!
publicstatic Page createPage(Page page, int \1!k)PZdTW
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totalRecords){ /'1y`j<
return createPage(page.getEveryPage(), v<SEGv-
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page.getCurrentPage(), totalRecords); k$c
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} gctaarB&
Cm4*sN.&)
/** A1q^E(}O
* the basic page utils not including exception P&GZe/6Y
p4t)Z#0
handler Z C93C7lJ
* @param everyPage cOb%SC[A{
* @param currentPage mQs$7t[>t
* @param totalRecords [z~Nw#
* @return page K[[k,W]qb
*/ .ndQ(B
publicstatic Page createPage(int everyPage, int jE#8&P~
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currentPage, int totalRecords){ /RM-+D:Y
everyPage = getEveryPage(everyPage); W,~1KUTc
currentPage = getCurrentPage(currentPage); DS C4
int beginIndex = getBeginIndex(everyPage, ]Yg EnZ
Dkb&/k:)
currentPage); bw\=F_>L
int totalPage = getTotalPage(everyPage, (Pd>*G\
zl\#n:|
totalRecords); d]3sC
boolean hasNextPage = hasNextPage(currentPage, sJoi fl
7
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totalPage); t {"iIz_S
boolean hasPrePage = hasPrePage(currentPage); Elp!,(+&6
{ 9 ".o,
returnnew Page(hasPrePage, hasNextPage, 'EV *-_k
everyPage, totalPage, G C'%s
currentPage, IFxI>6<&
ku?_/-ko]
beginIndex); .@Uz/j?>
} [MS.5+1Y
!j9i=YDb
privatestaticint getEveryPage(int everyPage){ mPin\-I
return everyPage == 0 ? 10 : everyPage; gN(hv.nQ
} <gLtX[v!CL
05B+WJ1
privatestaticint getCurrentPage(int currentPage){ m;f?}z_\$
return currentPage == 0 ? 1 : currentPage; YZRB4T9
} wF8\
j\f$r,4
privatestaticint getBeginIndex(int everyPage, int *]WXM.R8
LFyceFbm
currentPage){ od1omYsR
return(currentPage - 1) * everyPage; 1`lFF_stkP
} ~,2hP
~
^4pKsO3ul
privatestaticint getTotalPage(int everyPage, int o2 d~
suFOc
totalRecords){ T''+zk
int totalPage = 0; Ts .Zl{B
j7#GqVS'
if(totalRecords % everyPage == 0) i@5%d!J
totalPage = totalRecords / everyPage; /\cu!yiX
else ]Cn*C{
totalPage = totalRecords / everyPage + 1 ; [IFRwQ^%_O
;Ia1L{472m
return totalPage; a~F@3Pd
} ;J-Ogt @d7
V2{#<d-T!
privatestaticboolean hasPrePage(int currentPage){ 4oV_b"xz~
return currentPage == 1 ? false : true; &hN&nH"PC
} Tki/d\!+
$sF#Na4^
privatestaticboolean hasNextPage(int currentPage, e[mhbFf-
,'CWt]OS'
int totalPage){ 7&V^BW
return currentPage == totalPage || totalPage == |.O!zRm
gvqd1?0w
0 ? false : true; %K'*P56
} m}[~A@qD
N5s|a5
/Jf`x>eiH
} v7FRTrqjj
|vN@2h(|"
8UT%:DlxQ
ef}E.Bl
3
9{"T0
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。 eM=) >zl
'0')6zW5s
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 c48J!,jCd'
%;(|KrUN
做法如下: _~ZQ b
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 xPMyG);
B9IXa;
的信息,和一个结果集List: (GEi<\16[
java代码: (1AA;)`Kp
Di<J6xu
`JWYPsWk
/*Created on 2005-6-13*/ ]~00=nXFM/
package com.adt.bo; &1E~ \8U
MIlCUk
import java.util.List; XDdcq ]*|
O%K?l}e
import org.flyware.util.page.Page; @=NVOJy}c
e*2&s5 #RT
/** (Ef2
w['
* @author Joa B_"OA3d_
*/ w}W@M,.^
publicclass Result { &O6;nJEI
m/hi~.D9
private Page page; y|;8 :b32
?FV7|)f
private List content; dD^_^'i
j&[.2PW\
/** O/Mz?$8J
* The default constructor J4[x,(iq(
*/ x1:Pj
public Result(){ 52MCU l
super(); r($_>TS&"
} B2G5hbaA
Z0"&
/** Naf`hE9
* The constructor using fields cl8_rt
* 3W-NS~y
* @param page P10p<@?
* @param content E]H
*/ tC?Aso
public Result(Page page, List content){ LPapD@Z
this.page = page; u1;e*ty
this.content = content; otz_nF;E
} we\b]
2JA&{ch
/** %<wQ
* @return Returns the content. 3j+=3n,
*/ y4/>Ol]
publicList getContent(){
N8kb-2
return content; ) _9e@~,
} v$)@AE
/=muj9|+s
/** HTDyuqs
* @return Returns the page. 7"n)/;la
*/ 6)#- 5m
public Page getPage(){ )&Kn(l)
return page; +e0dV_T_>
} |
or 8d>,
T$n>7X-r
/** wWJQ~i?
* @param content xxLgC;>[
* The content to set. _b!;(~@p
*/ Nxbd~^j
public void setContent(List content){ n b0 Py>4
this.content = content; vn0cKz@
} Ez/\bE
N&I8nZ9
/** S2'`|uI
* @param page vJTfo#C|
* The page to set. .*EOVo9S
*/ R0Ax$Cv{
publicvoid setPage(Page page){ ^A *]&%(h
this.page = page; ;&+[W(7Sy
} Sv~YFS :oy
} @ate49W
*R_'$+
>9o,S3
IqhICC1V-
7>PF ~=
2. 编写业务逻辑接口,并实现它(UserManager, RwAbIXG{0
_.d}lK3$2
UserManagerImpl) + ZR(
java代码: ^MW\t4pZ
,bZ"8Z"lss
+CnyK(V
/*Created on 2005-7-15*/ |D;_:x9
package com.adt.service; HA^jk%53
U^M@um M
import net.sf.hibernate.HibernateException; E8T"{
R80
!j!Z%]7
import org.flyware.util.page.Page; )(h&Q?
Ar
%~#!NX
import com.adt.bo.Result; r{K\(UT]!
Bs+c2R
/** v>#Cg\
* @author Joa n!0${QVnS
*/ [2GXAvXsT
publicinterface UserManager { M1AZ}bc0]
:DZLjC
public Result listUser(Page page)throws ,}9f(`
G 2%
HibernateException; [;(]Jy
tA`mD >[
} *.kj]BoO
P]pmt1a
O"
%Hprx
E$]a?uA:
KI Ek/]<H
java代码: gCv"9j<j
Dk)@>l:gI,
Xtci0eS#V
/*Created on 2005-7-15*/ )^t!|*1LA
package com.adt.service.impl; P['X<Xt8
Bz~ -2#l
import java.util.List; 6RK ~Dl&g
=E;=+eqt
import net.sf.hibernate.HibernateException; jA4PDH f+
2Ryp@c&r^
import org.flyware.util.page.Page; uew0R;+oa
import org.flyware.util.page.PageUtil; ;EK(b
Y.DwtfE
import com.adt.bo.Result; +VSZhg,Np8
import com.adt.dao.UserDAO; wENzlXeOP
import com.adt.exception.ObjectNotFoundException; "#*Nnt
import com.adt.service.UserManager; 0-*Z<cu%l
&g*klt'B
/** j.k@6[R>?
* @author Joa jmkRP"ZnA
*/ C=>B_EO
publicclass UserManagerImpl implements UserManager { FQ+8J 7
}C=Quy%Z<
private UserDAO userDAO; (l
Lu?NpIi
^fkCyE;=
/** M6# \na
* @param userDAO The userDAO to set. )yHJ[
*/ @(Z( /P;:
publicvoid setUserDAO(UserDAO userDAO){ ;5<P|:^
this.userDAO = userDAO; 0r1g$mKb
} -Bj.hx*
FI\IY
R
/* (non-Javadoc) '4$lL6ly>
* @see com.adt.service.UserManager#listUser R"NGJu9
>OT\~C
(org.flyware.util.page.Page) LRWOBD
*/ doLkrEm&
public Result listUser(Page page)throws Ymq3ty]Pe
S2ark,sp6
HibernateException, ObjectNotFoundException { Zotz?jVVr
int totalRecords = userDAO.getUserCount(); uii7b7[w
if(totalRecords == 0) e[s5N:IUd3
throw new ObjectNotFoundException Z*9L'd"D|
f7Yz>To
("userNotExist"); 8fnR1mWG
page = PageUtil.createPage(page, totalRecords); e{5,'(1]
List users = userDAO.getUserByPage(page); xFOBF")
returnnew Result(page, users); A
6 :Q<
} QO@6VY@
Lj4&_b9
} u2 7S%2P
5Yl6?
jM*AL
X
|Td_S|:d
26M~<Ic
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 q&Q/?g>f
^b=XV&{q
询,接下来编写UserDAO的代码: sD2
^_w6j
3. UserDAO 和 UserDAOImpl: %8
qSv%_
java代码: IK3qE!,&U
w$b~x4y%
0F^]A"kF
/*Created on 2005-7-15*/ aRX
package com.adt.dao; 3x![8 x
)6G"*
import java.util.List;
P&mtA2
m*gj|1k
import org.flyware.util.page.Page; bjlkX[{}I
or7pJy%4"
import net.sf.hibernate.HibernateException; va^0JfQ
A';n6ne%i
/** ' X}7]y
* @author Joa @LcT-3 u
*/ qp\BV #E
publicinterface UserDAO extends BaseDAO { [yC"el6PM
/tP7uVL
R
publicList getUserByName(String name)throws QhCY}Q?X
v{.\iIg N
HibernateException; 66
N)
b~j~
publicint getUserCount()throws HibernateException; c#
xO<
{|XQO'Wg
publicList getUserByPage(Page page)throws TMww
]%Y\ZIS
HibernateException; %@P``
9k}<F z"^.
} dgslUg9z3g
l
DnMjK\M
Z:|9N/>T
VJg,~lQN#t
7G"7wYc>R
java代码: ,%Z&*n
SW#BZ3L
E+z18Lf?
/*Created on 2005-7-15*/ =53bLzr
package com.adt.dao.impl; )tD6=Iz^5
"XhOsMJ
import java.util.List; *> KHRR<N
gQ>2!Qc a-
import org.flyware.util.page.Page; tOM(U-7Z&
Px#$uU
import net.sf.hibernate.HibernateException; uB;_vC
import net.sf.hibernate.Query; [sj VRW-
ib]vX-
import com.adt.dao.UserDAO; JOHRmfqR
(]XbPW
/** `L\)ahM
* @author Joa thptm
*/ GRIa8>
public class UserDAOImpl extends BaseDAOHibernateImpl uY;R8CiD
Fu%X
implements UserDAO { :+:6_x
5B{k\H;
/* (non-Javadoc) l4 "\) ];
* @see com.adt.dao.UserDAO#getUserByName Y208b?=9w
SdxY>;
(java.lang.String) o%`npi1y
*/ ik5|,#}m&
publicList getUserByName(String name)throws LwOJ|jA(,
%`+'v_iu
HibernateException { ej52AK7
String querySentence = "FROM user in class j o_
sAb
E:w:4[neh
com.adt.po.User WHERE user.name=:name"; Qn.[{rw
Query query = getSession().createQuery P"F{=\V1`<
jV^C19
(querySentence); {6O0.}q]&
query.setParameter("name", name); ,H39V+Y*
return query.list(); [(|v`qMv/g
}
rN"Xz
2xn<E>]
/* (non-Javadoc) Pz@/|&]
* @see com.adt.dao.UserDAO#getUserCount() `(DJs-xD
*/ MCU9O
publicint getUserCount()throws HibernateException { Q0~j$Jc
int count = 0; /.$L"u
String querySentence = "SELECT count(*) FROM (ua q<Cvg
rl?7W];
user in class com.adt.po.User"; s<&[\U
Query query = getSession().createQuery TsHF
tj9S
0^#DNq*NQ
(querySentence); %8w9E=
count = ((Integer)query.iterate().next 3wC
R|ab}
M&y5AB0
()).intValue(); 2*u.3,aW
return count; hD
q2-X}
} -eml
g19S
/* (non-Javadoc) #3 bv3m
* @see com.adt.dao.UserDAO#getUserByPage ArzDI{1
@B`Md3$7
(org.flyware.util.page.Page) P^[/Qi}j
*/ Nfw YDY
publicList getUserByPage(Page page)throws OVR?*"N_
mW4%2fD[
HibernateException { m<: IFx#
String querySentence = "FROM user in class _ 08];M|
l}}UFEA^
com.adt.po.User"; *eUc.MX6x
Query query = getSession().createQuery ~Ltr.ci
_]|Qec)
(querySentence); <9ifPSvJ
query.setFirstResult(page.getBeginIndex()) B4yh3cf
.setMaxResults(page.getEveryPage()); N:x0w+Ca
return query.list(); {DBIonY];
} = .`jjDJ
v <Hb-~
} z[9UQU~x?
I:$"E%
>=
{QQl$ys/
fbC~WV#
M35Ax],:^
至此,一个完整的分页程序完成。前台的只需要调用 Bo
r7] #
y3IWfiz>/d
userManager.listUser(page)即可得到一个Page对象和结果集对象 ssl&5AS
8h.V4/?
的综合体,而传入的参数page对象则可以由前台传入,如果用 ^%#grX#
,2`~ NPb
webwork,甚至可以直接在配置文件中指定。 r]LCvsVa
AhxGj+
下面给出一个webwork调用示例: C1QV[bJK
java代码: mhzYz;}
7[KCWJ
CWlW/>yF
B
/*Created on 2005-6-17*/ o\6iq
package com.adt.action.user; 'UfeluMd
E5UcZ7
import java.util.List; <1@
(ioPH
GGnp Pp
import org.apache.commons.logging.Log; (V?@?25
import org.apache.commons.logging.LogFactory; Do*n#=
import org.flyware.util.page.Page; w sY}JT
[uR/M
import com.adt.bo.Result; };S0 G!
import com.adt.service.UserService; 4tJa-7
import com.opensymphony.xwork.Action; 5=Lq=,K$
8&E}n(XE
/** kMxjS^fr
* @author Joa Gvx[8I
*/ ^Mytp> 7
publicclass ListUser implementsAction{ *Km7U-BG
w> 979g
privatestaticfinal Log logger = LogFactory.getLog '*R%^RK
8_Z/ o5s
(ListUser.class); g`?:=G:a*
X9XI;c;b-
private UserService userService; [,g~m9
sN/+
private Page page; l[%lE
(E!!pz
privateList users; Z'M`}3O
5 DFZ^~
/* #Ufo)\x
* (non-Javadoc) 213\ehhG<
* >Ko[Xb-8^_
* @see com.opensymphony.xwork.Action#execute() `\b+[Nes
*/ *jCW.ZLY
publicString execute()throwsException{ J(iV0LAZb
Result result = userService.listUser(page); GAl+Zg##
page = result.getPage(); |4C^$
users = result.getContent(); LE;g
0s
return SUCCESS; jv&+<j`r
} ~&g a1r2v?
urZ8j?}c
/** )2.)3w1_4
* @return Returns the page. '^}+Fv<O
*/ Kf.T\V4%
public Page getPage(){ <qeCso
return page; {9'M0=
} qnIew?-*
fN[8N$1-
/** Ijedo/
* @return Returns the users. GdA.g
w
*/ n1J]p#nCa.
publicList getUsers(){ U^_D|$6
return users; fRHKQ(a#
} hh"-w3+
qrBZvJU
/** D}{b;Un
* @param page CqoG.1jJS
* The page to set. G{lcYP O
*/ N|dD!
publicvoid setPage(Page page){ $p$dKH
this.page = page; @ 4UxRp6+
} QLr9dnA
PT]GJ<K/
/** 4hAJ!7[A.
* @param users 3S"] u}
* The users to set. KIus/S5
RC
*/ O\Eqr?%L)
publicvoid setUsers(List users){ >K)2NLW\xA
this.users = users; I=rwsL
} Eipp~GD
"wM1 qX
/** DxS sg
* @param userService 2@Lbfo A
* The userService to set. y4jU{,
*/ 8 ws$k\>
publicvoid setUserService(UserService userService){ 92[a;a
this.userService = userService; qL
5>o>J
} )K0i@hM(n
} $3;Upgv
G|4^_`-
G+WM`:v8%
GP,<`l&
I1=(. *B}
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ;=~Xr"(/z
~`cwG`
'N
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 S!Jh2tsg`-
#R5U
么只需要: ,=PKd&
java代码: 1oY^]OD]W
PCE4W^ns
OAe#Wf!c
<?xml version="1.0"?> tP(h9|[N
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork bcz-$?]
sYn[uPefj
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 2 y8~#*O
lU.Kc
1.0.dtd"> rAukHeH
j]5WK_~M
<xwork> ZFxLBb:
EX
"|H.(
<package name="user" extends="webwork- ,YLF+^w-
P+(i^=S
interceptors"> q,l)I+
g>j| ]6
<!-- The default interceptor stack name SF<Vds}A2
f =s&n}
--> Mr3-q
<default-interceptor-ref MC!ZX)mF
UY>v"M
name="myDefaultWebStack"/> @,OT/egF4:
$g\&5sstE
<action name="listUser" ]z ==
1wn&js C
class="com.adt.action.user.ListUser"> Pqp *
<param w"zE_9I\
=$^MQ\S0p
name="page.everyPage">10</param> !a-b6Aa
<result mG2'Y) Sz
E4oz|2!m
name="success">/user/user_list.jsp</result> m&Y i!7@(
</action> jai|/"HSXw
;_"U "?h_J
</package> +c$I&JO
#@f[bP}a
</xwork> wWjG
JvJ
m7jA
,~O
oy\B;aAK
H3KTir"on
nHst/5dA
< n?=|g
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 l54
m22pfv
vNDu9ovs-
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 3Qn!y\#
mY-hN|
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 eph)=F$
Zq"7,z7
EU+cca|qS9
m#5_%3T
B#l?IB~
我写的一个用于分页的类,用了泛型了,hoho ]\c,BWC@e
\vbk#G
hH
java代码: F:g= i}7
ff2d@P,!
%,V
YiW0
package com.intokr.util; E`;;&V q-
5J.0&Dda
import java.util.List; 3MBN:dbQ
v}(6 <wnnS
/** oh-|'5+,;h
* 用于分页的类<br> cDkV;$
* 可以用于传递查询的结果也可以用于传送查询的参数<br> N$I03m
* 6d|q+]x_n
* @version 0.01 5LW}h^N
* @author cheng ! fl4"
*/ dF@)M
public class Paginator<E> { +}kgQ^
privateint count = 0; // 总记录数 k2^ a$k}
privateint p = 1; // 页编号 j;nb?;
privateint num = 20; // 每页的记录数 ;`j/D@H
privateList<E> results = null; // 结果 X@wm1{!
ig#r4nQ=
/** %V_-%/3Z
* 结果总数 /n5n
)P@L
*/ u?H 2%hD
publicint getCount(){
6ghx3_%w
return count; D ]03eu
} 't (O$
kuMKX`_
publicvoid setCount(int count){ 1Y/$,Oa5
this.count = count; U.oksD9v
} _t>"5s&i
)}lRd#V
/** ^))RM_ic
* 本结果所在的页码,从1开始 p<GR SJIk=
* !PUZWO
* @return Returns the pageNo. X&\d)/Y
*/ kI\tqNJ i
publicint getP(){ J./d!an
return p; QfpuZEUK
} Hh[Tw&J4
]!"S+gT*C
/** =t0tK}Y+4
* if(p<=0) p=1 7(k^a)~PL
* sfD5!Z9#1
* @param p Kx`/\u=/
*/ S33j?+Vs
publicvoid setP(int p){ ,[rPe\w.z
if(p <= 0) e{w>%)rcP
p = 1; :QQlI
this.p = p; k3Cz9Vt%
} hvV_xD8|
ODw`E9
/** Xq#Y*lKVD
* 每页记录数量 |L3X_Me
*/ x hs#u
publicint getNum(){ #KpY6M-H
return num; eny/
fm
} Ve 3 ;
n(ir[w#,]"
/** EMvHFu
* if(num<1) num=1 ,XKCz ]8V
*/ sH#X0fG
publicvoid setNum(int num){ _=f=f cl
if(num < 1) epD?K
num = 1; @tUoD>f
this.num = num; #Z,E><t
} ':h
=*v8a
Rd&9E
/** kyYLP"oB=
* 获得总页数 _r Y,}\
*/ ;@mRo`D`
publicint getPageNum(){ Sr Ca3PA
return(count - 1) / num + 1; _'0
@%P%
} X"asfA[6K
},-*
/** Tenf:Hm/k
* 获得本页的开始编号,为 (p-1)*num+1 q3e8#R)l
*/ }(FPV*mS
publicint getStart(){ S7iDTG_@t
return(p - 1) * num + 1; <E,%@
} lTRl"`@S
PH3 >9/H
/** =6 r:A<F!n
* @return Returns the results. #$ thPZ
*/ x i~uv?f
publicList<E> getResults(){ -b;|q.!
return results; `u'bRp
} ?}p:J{
nA7M8HB
public void setResults(List<E> results){ C|-pD
this.results = results; N#xG3zZl|N
} ^_+XDO
B}?IEpYp
public String toString(){ ;\;M =&{}
StringBuilder buff = new StringBuilder -1|iz2^N
dE`-\J
(); TbVn6V'
buff.append("{"); < B g8,;
buff.append("count:").append(count); ;T +pu>)
buff.append(",p:").append(p); j+4H}XyE
buff.append(",nump:").append(num); *Ust[u
buff.append(",results:").append G'z{b$?/[
=<z.mzqu5
(results); {r85l\u)Q\
buff.append("}"); TX8<J>x
return buff.toString(); cQj-+Tmu
} +/{L#e>
&K+0xnUH
} RD,5AShP
qPGuo5^
xJ8%<RR!t