Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 U+g<lgH1J
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 a5%IjgQ&z
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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 +4k7ti1Qb
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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 '>r"+X^W
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分页支持类: @0q*50
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java代码: ZNG{:5u,
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package com.javaeye.common.util; GG[$-
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import java.util.List; nD;8)VI'I
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publicclass PaginationSupport { yn-TN_/Y,
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publicfinalstaticint PAGESIZE = 30; 8p~G)J3U
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privateint pageSize = PAGESIZE; q3R?8Mb
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privateList items; d512Y[ R
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privateint totalCount; ]Q0+1'yuK
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privateint[] indexes = newint[0]; Md ,KW#
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privateint startIndex = 0; #:3~I
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public PaginationSupport(List items, int mmrz:_
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totalCount){ :u>9H{a
setPageSize(PAGESIZE); \d{S3\7
setTotalCount(totalCount); Lj03Mx.2S
setItems(items); 6)~J5Fb
setStartIndex(0); \ )n'Ywr
} >0qe*4n|M
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public PaginationSupport(List items, int . 'rC'FT
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totalCount, int startIndex){ vS'5Lm
setPageSize(PAGESIZE); p-o!K\o-1
setTotalCount(totalCount); iSxuor^;
setItems(items); VVyms7
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setStartIndex(startIndex); ~!{y3thZ
} o>Jr6:D(
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public PaginationSupport(List items, int YX:[],FP
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totalCount, int pageSize, int startIndex){ $'>h7].
setPageSize(pageSize); "FT(U{^7d
setTotalCount(totalCount); Z6xM(*vg
setItems(items); /xcl0oe(
setStartIndex(startIndex); N61\]BN<
} r*t\\2
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publicList getItems(){ W{v-(pW
return items; A[O' e
} COf>H0^%Q
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publicvoid setItems(List items){ ESAFsJ$r;
this.items = items; s5'So@L8
}
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Xm!;
publicint getPageSize(){ WMLsKoby
return pageSize; i5 F9*
} R87e"m/C%
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publicvoid setPageSize(int pageSize){ _Q1[t9P"
this.pageSize = pageSize; MKN],l
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} 60 z =bd]
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publicint getTotalCount(){ /
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return totalCount; ir ^XZVR
} wNgS0{}&`
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publicvoid setTotalCount(int totalCount){ ;K9rE3
if(totalCount > 0){ oH|<(8efD
this.totalCount = totalCount; zn@yt%PCV
int count = totalCount / +(|6Wv
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pageSize; E}WO?xxv74
if(totalCount % pageSize > 0) $m-rn'Q
count++; CAl]Kpc
indexes = newint[count]; b];p/V#
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for(int i = 0; i < count; i++){ $M=W`E[g
indexes = pageSize * {)8!> K%G
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} :"oQ _bLT
}else{ xi
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this.totalCount = 0; ^
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} LiF(#OuZ
} S!;:7?mq
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publicint[] getIndexes(){ 'sCj|=y2Qc
return indexes; c$>$2[*=
} pjP
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publicvoid setIndexes(int[] indexes){ S EeDq/h
this.indexes = indexes; eQRY xx{
} vF ,iHzv
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publicint getStartIndex(){ WI$MT6
return startIndex; ,9C~%c0Pw
} U- a+LS
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publicvoid setStartIndex(int startIndex){ :nHa-N3
if(totalCount <= 0) pGO)9?j_N
this.startIndex = 0; Dr!g$,9
elseif(startIndex >= totalCount) ?U`~,oI0
this.startIndex = indexes RN%*3{-
,' m<YTF
[indexes.length - 1]; *"pf3x6
elseif(startIndex < 0)
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this.startIndex = 0; H?(I-vO
else{ &7 YTz3aj
this.startIndex = indexes C&QT-|
[0(+E2/:2
[startIndex / pageSize]; a\Ond#1p
} d}.*hgk
} jxU z-U-
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publicint getNextIndex(){ A #y,B
int nextIndex = getStartIndex() + ;L gxL
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pageSize; f;nO$h[Qb
if(nextIndex >= totalCount) kT+Idu
return getStartIndex(); X. =%
else Ae0jfTv
return nextIndex; mQ@A3/= `
} uP-I7l0i1
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publicint getPreviousIndex(){ o"Dk`L2
int previousIndex = getStartIndex() - 2)A% 'Akf
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pageSize; K6=i\
if(previousIndex < 0) {v,O
return0; ue5C
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else E26 zw9d
return previousIndex; Sl8A=Ez
} h}k/okG
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} mP@<UjxI
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抽象业务类 TA.ugF)h
java代码: .^fVm
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/** 6,707h
* Created on 2005-7-12 '9+JaB
*/ }J~
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package com.javaeye.common.business; V5MLzW\8
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import java.io.Serializable; c /G4@D>
import java.util.List; 7Z#r9Vr
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import org.hibernate.Criteria; xIN&>D'|N
import org.hibernate.HibernateException; vnNX)$f
import org.hibernate.Session; P9Yw\
import org.hibernate.criterion.DetachedCriteria; Y~P1r]piB
import org.hibernate.criterion.Projections; {W[OjPC~F
import 6z6\-45
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org.springframework.orm.hibernate3.HibernateCallback; <Be:fnPX7
import (V:z7
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org.springframework.orm.hibernate3.support.HibernateDaoS 8gQg#^,(t
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upport; ScgaWJ
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import com.javaeye.common.util.PaginationSupport; |4J ;s7us
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public abstract class AbstractManager extends +:a#+]g
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HibernateDaoSupport { ig Q,ZY1
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privateboolean cacheQueries = false; S~~G0GiW
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privateString queryCacheRegion; Y
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publicvoid setCacheQueries(boolean r9nyEzk
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cacheQueries){ ZU=omRh5
this.cacheQueries = cacheQueries; xppl6v(
} BwLggo
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publicvoid setQueryCacheRegion(String gQ< >S
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queryCacheRegion){ g[D(]t\#x
this.queryCacheRegion = Y<4%4>a
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queryCacheRegion; WE-cq1)
} s?fO)7ly
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publicvoid save(finalObject entity){ 0tL#-47
getHibernateTemplate().save(entity);
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} FO"sE`
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publicvoid persist(finalObject entity){ &V`~ z
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getHibernateTemplate().save(entity); ftr8~*]O
} 9+"R}Nxv^
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publicvoid update(finalObject entity){ gMGX)Y ,=/
getHibernateTemplate().update(entity); AYVkJq ?
} I"=a:q
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publicvoid delete(finalObject entity){ $?HOke
getHibernateTemplate().delete(entity); n A<#A
} F}f/cG<X
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publicObject load(finalClass entity, Y<]A5cm
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finalSerializable id){ X6T*?t3!9[
return getHibernateTemplate().load \>DMN #
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(entity, id); m]7oTmS
} n$*e(
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publicObject get(finalClass entity, #OQT@uF!
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finalSerializable id){ j3Sz+kOf,
return getHibernateTemplate().get Z[,A>tJ
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(entity, id); j>}<FW-N
} 6h5,XcO4
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publicList findAll(finalClass entity){ {:63% j
return getHibernateTemplate().find("from <>Nq]WqA
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" + entity.getName()); 5x2m]u
} N!{waPbPi
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publicList findByNamedQuery(finalString <Z>p1S
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namedQuery){ J7RO*.O&Iq
return getHibernateTemplate ![ce=9@t<
[X\<C '<
().findByNamedQuery(namedQuery); ~+~^c|
} )B!64'|M
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publicList findByNamedQuery(finalString query, 1.U9EuI
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finalObject parameter){ RT~6 #Caf
return getHibernateTemplate MYlPG1X=?
ta*6xpz-\Q
().findByNamedQuery(query, parameter); 3d>3f3D8;
} e8Y;~OAj[
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publicList findByNamedQuery(finalString query, s"xiGp9
)HL[_WfY
finalObject[] parameters){ Mb1K:U
return getHibernateTemplate 0dKv%X#\
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FtX}
().findByNamedQuery(query, parameters); t0"2Si
} b~u53
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publicList find(finalString query){ \Wn0,%x2
return getHibernateTemplate().find $Lc-}m9n
}jI=*
(query); 4#fgUlV
} }vXf}2C
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publicList find(finalString query, finalObject k^:+Pp
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parameter){ 2Sha&Z*CE
return getHibernateTemplate().find &x#3N=c#
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(query, parameter); 1M<;}hJ{/
} u]uUm1Er
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public PaginationSupport findPageByCriteria .!^}sp,E
}Y=X{3+~.
(final DetachedCriteria detachedCriteria){ F5(D A
return findPageByCriteria AB0>|.
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); .zQ'}H1.C
} 'k1vV
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public PaginationSupport findPageByCriteria *$Tz g!/
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(final DetachedCriteria detachedCriteria, finalint ro8c-[V
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startIndex){ ,mY3oyu
return findPageByCriteria rF:l+I]
<AN=@`+
(detachedCriteria, PaginationSupport.PAGESIZE, C
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: 6|nXL
startIndex); [a2Q ^ab
} i9O;D*
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public PaginationSupport findPageByCriteria Tz<@k
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(final DetachedCriteria detachedCriteria, finalint q Xj]O3
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pageSize, 62Q`&n6
finalint startIndex){ ~ ~U,
return(PaginationSupport) l2ww3)Z
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getHibernateTemplate().execute(new HibernateCallback(){ G{!adBna
publicObject doInHibernate #BOLq`9f
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(Session session)throws HibernateException { }Lc8tj<
Criteria criteria = 0\tdxi
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detachedCriteria.getExecutableCriteria(session); e{k)]]J
int totalCount = in>.Tax*
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((Integer) criteria.setProjection(Projections.rowCount SYaL@54
h#?)H7ft
()).uniqueResult()).intValue(); G$7!/O%#_
criteria.setProjection hG! |ts
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(null); i^_?C5
List items = r(i!". Z
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criteria.setFirstResult(startIndex).setMaxResults sNbCOTow
f`Wces=5
(pageSize).list(); YLkdT%
PaginationSupport ps = y|h:{<
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new PaginationSupport(items, totalCount, pageSize, <HMmsw
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startIndex); ,Z aPY
return ps; ki<4G
} }:9UI
}, true); yT pvKCC
} <52)
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public List findAllByCriteria(final 3uJ>:,~r
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DetachedCriteria detachedCriteria){ T.B}k`$
return(List) getHibernateTemplate *R8qnvE\()
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().execute(new HibernateCallback(){ 1Uf8ef1,
publicObject doInHibernate m>8tA+K)+)
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(Session session)throws HibernateException { 6SVh6o@]
Criteria criteria = Ps=<@,dks
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detachedCriteria.getExecutableCriteria(session); 6eq`/~#
return criteria.list(); Y V#|qb
} =Xu(Js-
}, true); eczS(KoL4
} F?.J1]
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public int getCountByCriteria(final OaCp3No
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DetachedCriteria detachedCriteria){ yr,Oq~e
Integer count = (Integer) wW1>#F
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getHibernateTemplate().execute(new HibernateCallback(){ n.tJ-l5[
publicObject doInHibernate O9jpt>:kZ
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(Session session)throws HibernateException { fNNik7
Criteria criteria = 4M3{P
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detachedCriteria.getExecutableCriteria(session); d`ESe'j:
return 6j5?&)xJ
bP3S{Jt-|
criteria.setProjection(Projections.rowCount ^_o9%)RL(
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()).uniqueResult(); [bZASeh
} <lFQ4<"m
}, true); #`Gh8n#
return count.intValue(); Zg2F%f$Y
} QJKVNOo
} mvrg!/0w
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用户在web层构造查询条件detachedCriteria,和可选的 ?~fuMy B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {nyVC%@Y
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PaginationSupport的实例ps。 E])X$:P?
WTZr{)e
ps.getItems()得到已分页好的结果集 }2i3
ps.getIndexes()得到分页索引的数组 tW7*(D
ps.getTotalCount()得到总结果数 {nl4(2$
ps.getStartIndex()当前分页索引 =`y.L5
ps.getNextIndex()下一页索引 *3r{s'm
ps.getPreviousIndex()上一页索引 8jxs%N,aI
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 8 ?+t+m[
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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 ~.'NG?
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一下代码重构了。 #w<:H1,4
jf'#2-
我把原本我的做法也提供出来供大家讨论吧: BoMf#l.3B
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首先,为了实现分页查询,我封装了一个Page类: ob3Z
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java代码:
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/*Created on 2005-4-14*/ KN"V(<!)~
package org.flyware.util.page; _8G
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/** 8LouCv(>
* @author Joa 5
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* '5vgpmn
*/ 4lqowg0
publicclass Page { q>X%MN y
bWAVBF
/** imply if the page has previous page */ u teI[Q
privateboolean hasPrePage; (&x#VmDL
{}TR'Y4
/** imply if the page has next page */ R0v5mD$:G
privateboolean hasNextPage; z9#iU>@
1*!`G5c,}
/** the number of every page */ {Noa4i
privateint everyPage; ua-cX3E
WV'FW)%
/** the total page number */ G()- NJ{
privateint totalPage; aH1mW;,1u
fGD#|a;,
/** the number of current page */ b1A8 -![
privateint currentPage; k!lz_Y
l'2a?1/q
/** the begin index of the records by the current I}a iy.l
@I '_
query */ LOkNDmj
privateint beginIndex; 6k=ink-/
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/** The default constructor */ 9rn[46s`
public Page(){ _e;$Y#`EO
z$d/Vz,a
} ,\FJVS;NeJ
Y M_\ ZK:
/** construct the page by everyPage 9OC!\'
8
* @param everyPage 27t23@{YL
* */ 'RlPj0Cg
public Page(int everyPage){ JKkR963 O
this.everyPage = everyPage; jI8qiZ);~
} yBPaGZ{f
C>qKKLZ
/** The whole constructor */ Jz!8Xg%a
public Page(boolean hasPrePage, boolean hasNextPage,
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}lk_Oe1
8W]6/st?]
int everyPage, int totalPage, pOCLyM9c
int currentPage, int beginIndex){ ueiXY|
this.hasPrePage = hasPrePage; Q`Q%;%t
this.hasNextPage = hasNextPage; 'wd-!aZAd
this.everyPage = everyPage; SY`
U]-h
this.totalPage = totalPage; A(mU,^
this.currentPage = currentPage; "(hhb>V1Wl
this.beginIndex = beginIndex; R^.oM1qu|
} =-`}(b2N
*:q3<\y{
/** 7J]tc1-re
* @return Yd4J:
* Returns the beginIndex. _M/ckv1q@
*/ D-/K'|b
publicint getBeginIndex(){ `o6Hm
return beginIndex; ag-\(i;K]
} m"~^-mJ-
9ZL3p!
/** @LS*WJ< w-
* @param beginIndex 8"4&IX
* The beginIndex to set. lEBt<
*/ ,OX(z=i_
publicvoid setBeginIndex(int beginIndex){ #cqia0.H
this.beginIndex = beginIndex; ;~$_A4;
} Hb KJ&^
gL(ny/Ob9
/** -,Q
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* @return W27EU/+3
* Returns the currentPage. iw\RQ
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*/ ec:?Q0
publicint getCurrentPage(){ ISI\<qx
return currentPage; 8'Z#sM^E
} " r!O9X6
!e?GS"L~
/** O!}TZfC
* @param currentPage Cg/L/0Ak
* The currentPage to set. /2K4ka<?7
*/ =h?WT*
publicvoid setCurrentPage(int currentPage){ y]B?{m``6
this.currentPage = currentPage; 7u!i)<pn
} )z/+!y
P {x`eD0
/** GqXnOmk
* @return {H+~4XG
* Returns the everyPage. )\C:|
*/ J#7\R':}zl
publicint getEveryPage(){ 'ao<gTUbu
return everyPage; (PjC]`FK
} LMf_wsp
}1P>^I"[Y
/** |*W`}i
* @param everyPage JzJS?ZF
* The everyPage to set. `H6-g=C
*/ 5-M EOy(
publicvoid setEveryPage(int everyPage){ b-8{bP]n
this.everyPage = everyPage; _ji"##K
} n*6Oa/JG7
#1i&!et&/
/** EELS-qA
* @return ,y}?Z8?63
* Returns the hasNextPage. 7q<2k_3<
*/ &13qlc6
publicboolean getHasNextPage(){ k{<]J5{7
return hasNextPage; 'c3P3`o,;
} UI}v{05]
xJtblZ1sr
/** :?%$={m
* @param hasNextPage Hn5:*;N
* The hasNextPage to set. l2"{uCcA
*/ +jePp_3$O
publicvoid setHasNextPage(boolean hasNextPage){ v1Tla]d
this.hasNextPage = hasNextPage; )$XW~oA'
} ld8 E!t[
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/** iB;EV8E
* @return ES[H^}|Gi
* Returns the hasPrePage. tLXwszR0r
*/ #T1py@b0zA
publicboolean getHasPrePage(){ YIv!\`^ \
return hasPrePage; 3-z;pk
} ]zEatY
1*\JqCR
/** p
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* @param hasPrePage z^z_!@7v
* The hasPrePage to set. 0|kkwZVPn
*/ P` Hxj> {
publicvoid setHasPrePage(boolean hasPrePage){ InnjZ>$
this.hasPrePage = hasPrePage; W($}G_j[B1
} 4RCD<7
egMl(~D
/** RKoM49W
* @return Returns the totalPage. jC3ta
* J jRz<T;
*/ f%fD>a
publicint getTotalPage(){ `yYo Vu*
return totalPage; U.]5UP:a
} JDcc`&`M
e 4-
/** NUBf>~_}
* @param totalPage -j1?lY
* The totalPage to set. Vmq:As^a
*/ l"70|~
publicvoid setTotalPage(int totalPage){ w U".^
+
this.totalPage = totalPage; ]X
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}
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} <d89eV+
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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''`Tf
LpCJfQ
个PageUtil,负责对Page对象进行构造: KE>|,Ur
java代码: v_M-:e3`
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@r7ekyO8)
/*Created on 2005-4-14*/ Vwxb6,}Z
package org.flyware.util.page; P2la/jN
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import org.apache.commons.logging.Log; &QHZ]2%U
import org.apache.commons.logging.LogFactory; zh8\
_>+
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/** HK_Vk\e
* @author Joa = BcKWC
* []^fb,5a
*/ <'WS -P%U
publicclass PageUtil { M_
* KA
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privatestaticfinal Log logger = LogFactory.getLog @">^2
&CP]+ at
(PageUtil.class); kAc8[Hn
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/** D,R"P }G
* Use the origin page to create a new page >3aB{[[N
* @param page 4FwtC"G3
* @param totalRecords `Vph=`0
* @return CMu/n]?c
*/ ckDWY<@v
publicstatic Page createPage(Page page, int t`F<lOKj
>|j8j:S[
totalRecords){ i|N%dl+T=
return createPage(page.getEveryPage(), :$k];
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page.getCurrentPage(), totalRecords); Bs?B\k=
} eKpWFP0
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/** 4~8!3JH39
* the basic page utils not including exception o2'^MxKb T
{"rYlN7,
handler {&u`d.Lk2p
* @param everyPage 2!@ER i
* @param currentPage hYvWD.c}
* @param totalRecords ]lQLA
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* @return page g>gVO@"b2
*/ py-5 :g}d
publicstatic Page createPage(int everyPage, int n1Ic[cM}
#_(t46
currentPage, int totalRecords){ @%"+;D
everyPage = getEveryPage(everyPage); )By#({O
currentPage = getCurrentPage(currentPage); M\m6|P
int beginIndex = getBeginIndex(everyPage, ,a6Oi=+>/U
b=87k
currentPage); 9nGS"E l{
int totalPage = getTotalPage(everyPage, PiL[&_8g
Hl|EySno
totalRecords); w'i8yl
bZ
boolean hasNextPage = hasNextPage(currentPage, {OIktG2gZ
{tKi8O^Rb
totalPage); rjaG{ i
boolean hasPrePage = hasPrePage(currentPage); OYYk[r
Zqi;by%
returnnew Page(hasPrePage, hasNextPage, K^6fg,&
everyPage, totalPage, A#;TY:D2
currentPage, \I-bZ|^
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beginIndex); m)\wbkC
} 506AvD
sKCfI]
privatestaticint getEveryPage(int everyPage){ <>l!
return everyPage == 0 ? 10 : everyPage; g&]n:qx
} -a+oQP]O
R?Ys%~5
privatestaticint getCurrentPage(int currentPage){ RCC~#bb
return currentPage == 0 ? 1 : currentPage; y+aL5$x6
} UL3++bt
EJByYk
privatestaticint getBeginIndex(int everyPage, int ^`*p;&(K\^
[&MhAzF
currentPage){ hLo'q^mGr
return(currentPage - 1) * everyPage; B[IqLD'6
} Z*Lv!6WS
h*lU&8)m\
privatestaticint getTotalPage(int everyPage, int .E/NlGm[
cedH#;V!j
totalRecords){ ]"X} FU
int totalPage = 0; .dw;b~p
:k&5Z`>)
if(totalRecords % everyPage == 0) _GtG8ebr
totalPage = totalRecords / everyPage; lm[LDtc
else p=jIDM'
totalPage = totalRecords / everyPage + 1 ; $T2n^yz
`21$e
return totalPage; G5Z_[Q~z
} y9::m]s
gPf^dGi7t
privatestaticboolean hasPrePage(int currentPage){
gI5Fzk@:
return currentPage == 1 ? false : true; #U?=D/
} nq,P.~l
d>bS)
privatestaticboolean hasNextPage(int currentPage, "raC?H
z$]HZ#aRE
int totalPage){ p6*|)}T_%
return currentPage == totalPage || totalPage == Kc#42C;t/
.!2Ac
0 ? false : true; \0bZ1"
} mA" 82"
) mG
Xxmvg.Nl
} OE8H |?%
k<.VR"I
p
@'lO~i
no
UXRQ
8 aC]" C
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。 =>u9k:('9
];7/DM#Np
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 wPRs.(]_
Zt{\<5j
做法如下: a";xG,U
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !<AY0fpY
g|
M@/Dl
的信息,和一个结果集List: ^hIKDc!.m
java代码: EwuBL6kN
eT ZQ[qMp
lKA2~ o
/*Created on 2005-6-13*/ K4|{[YpPB
package com.adt.bo; I/Q5Y- atg
]>"q>XgnI
import java.util.List; KX $Q`lM
'X]my
import org.flyware.util.page.Page; ndxijqw
wJb"X=i*
/** {z0PB] U
* @author Joa M
hJ;)(
*/ EVE<LF?
publicclass Result {
}29Cm$p
*s}j:fJ
private Page page; r<XlIi
I]B[H6
private List content; 0ofl,mXW
cd?a rIV5
/** Z`97=:W
* The default constructor |@lVFEl]
*/ $" `9QD~
public Result(){ Mz:t[rfs
super(); r\f|r$i
} }RPeAcbU_
_3{,nhkf:!
/** -mPrmapb3
* The constructor using fields 7iM;X2=7}
* % m0x]
* @param page ?&>H^}gDZ
* @param content }y P98N5o
*/ /{7we$+,p
public Result(Page page, List content){ AYLCdCoK.
this.page = page;
l6uUS
this.content = content; K-f\nr
} cQ<* (KU
Xy'qgK?
/** Vo-]&u&cr
* @return Returns the content. 5q>u]n9]
*/ Zd]2>h
publicList getContent(){ OcLFVD=
return content; _Sxp|{H0
} eOI#T'5
cojbuo
/** 8OW504AD
* @return Returns the page. h1uD >heGl
*/ xB&6f")
public Page getPage(){ .wv!;
return page; va_TC!{;
} W2([vRT
ok+-#~VTn
/** .7EZB
* @param content &ivPY
* The content to set. }bxx]rDl
*/ oL69w1
public void setContent(List content){ bAl0z)p
this.content = content; GP/Gv
} ;zl/
av*M#
/** gc6T`O-_;
* @param page B hnwb0b<
* The page to set. }:5>1FfX=
*/ D@yuldx'/
publicvoid setPage(Page page){ :/
yR
this.page = page; 4{1.[##]o
} ;PrL)!
} ?fXlrJ
>&kb|)
Pv(icf
l|
Nu%JI6&R
95G*i;E
2. 编写业务逻辑接口,并实现它(UserManager, 9ywPWT[^
.+"SDtoX
UserManagerImpl) T'TxC)
java代码: s`$px2Gw
vs)1Rm
@Fl&@ $
/*Created on 2005-7-15*/ cKj6tT"=O
package com.adt.service; [Bz'c1
uPtHCP6
import net.sf.hibernate.HibernateException; sa71Vh{
&2!F:L
import org.flyware.util.page.Page; .7nr :P
&$?i
import com.adt.bo.Result;
"w\Iz]
W]v[Xm$q
/** Je6=N3)
* @author Joa oVc
l (
*/ r|WoM39bp
publicinterface UserManager { 0*.>
>rI
]v^;]0vcr
public Result listUser(Page page)throws U/JeEI%L
@zJhJ'~Sl
HibernateException; AjQ^
{P
M zLx2?
} 7 vS]O$w<4
?=]*r>a3
Q(}TN,N
|
ZI ~#V
p5KM(N6f
java代码: f]BG`rJX
E&/D%}Wl
"5-S:+
/*Created on 2005-7-15*/ V+()`>44
package com.adt.service.impl; oj7X9~ nd
w:z@!<
import java.util.List; tzxp0&:Z].
m_TZY_;
import net.sf.hibernate.HibernateException; jaAv_=93f
U/B1/96lJ
import org.flyware.util.page.Page; d`|W6Do
import org.flyware.util.page.PageUtil; %KeQp W
G~{xTpL
import com.adt.bo.Result; X^#.4:>.
import com.adt.dao.UserDAO; S!GjCog^J
import com.adt.exception.ObjectNotFoundException; Cl;B%5yl
import com.adt.service.UserManager; sq_N!
eXa a'bTx
/** sg(L`P
* @author Joa H7e/6t<x
*/ #zcp!WE.OI
publicclass UserManagerImpl implements UserManager { <%JRZYZ
]]s_ 8u3
private UserDAO userDAO; sX3Vr&r
j~G^J
/** F6T@YSP
* @param userDAO The userDAO to set. bp6 La`+
*/ $a6&OH/
publicvoid setUserDAO(UserDAO userDAO){ [)`9euR%
this.userDAO = userDAO; *|x2"?d-F:
} -#b-@sD
-;z&">
/* (non-Javadoc) Q^v8n1
* @see com.adt.service.UserManager#listUser 7cn"@h rJ
;<#fZ0(l;
(org.flyware.util.page.Page) hGH{Xp[mW
*/ <?P UF,
public Result listUser(Page page)throws B{W2D
oOuhbFu
HibernateException, ObjectNotFoundException {
1;ulqO
int totalRecords = userDAO.getUserCount(); i4.s_@2Y
if(totalRecords == 0) n%Xw6qV:
throw new ObjectNotFoundException =VlO53Hy{
/|y3M/;F
("userNotExist"); }[PbA4l.g
page = PageUtil.createPage(page, totalRecords); Y9m'RFZr
List users = userDAO.getUserByPage(page); gU/\'~HG
returnnew Result(page, users); V|{ )P@Q
} #kX=$Bzk
joifIp_
} Zg7~&vs$
xZS
:H<u@%
?T5^hQT
{"e/3
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 0x0.[1mB
..7"&-?g{4
询,接下来编写UserDAO的代码: 1+o >#8D
3. UserDAO 和 UserDAOImpl: =L<OTfVE
java代码: Y,?
O#7fkL
C["^%0lj
/*Created on 2005-7-15*/ dH!k{3bL
package com.adt.dao; @6i^wC
VVJhQ bP
import java.util.List; 1,W%t\D
"Q+'lA[}
import org.flyware.util.page.Page; 2s
EdN$O
IqEY.2KN
import net.sf.hibernate.HibernateException; Tm_vo-
f9D7T|J?10
/** \+v_6F
* @author Joa ?4q6>ipx
*/ 'E0{zk
publicinterface UserDAO extends BaseDAO { f+s'.z%
7 .+kcqX
publicList getUserByName(String name)throws S'Q$N-Dy
Y_%\kM?7
HibernateException; AY0o0\6cw
f9JD_hhP'
publicint getUserCount()throws HibernateException; s.KJYP
]&VD$Z984r
publicList getUserByPage(Page page)throws [_qBp:_j?s
Z|d_G}
HibernateException; }tx~y-QQ
>S{1=N@Ev=
} . xX xjl
,y2ur 2
b_Ba0h=
I]Wb\&$
)TyL3Z\>(
java代码: iml*+t
%dL|i2+*8
"=|yM~V
/*Created on 2005-7-15*/ Ff& VBm
package com.adt.dao.impl; X\$|oiR
[ne4lWaE<y
import java.util.List; -.g5|B
cY#TH|M
import org.flyware.util.page.Page; ~AK!_EOs`
;'tsdsu}
import net.sf.hibernate.HibernateException; `"(7)T{
import net.sf.hibernate.Query; /Rk5n
3Luv$6
import com.adt.dao.UserDAO; :":W(O
OU9=O>
/** s&y
* @author Joa 4_t
aCK
*/ yYdXAenQ
public class UserDAOImpl extends BaseDAOHibernateImpl fgl"ox
X^9_'T9
implements UserDAO { pPh_p@3I
{(7.X4\x
/* (non-Javadoc) q97Dn[>3
* @see com.adt.dao.UserDAO#getUserByName +#Ov9b
_BtlO(0&
(java.lang.String) _V:D7\Gs
*/ S~/iHXm
publicList getUserByName(String name)throws 1Q?hskL
x6,S#p
HibernateException { g:;v]
String querySentence = "FROM user in class S3qUzK
g"C$B Fc
com.adt.po.User WHERE user.name=:name"; r7ywK9UL
Query query = getSession().createQuery {Fb)Z"8]
ej%C<0/%n
(querySentence); \~y>aYy
query.setParameter("name", name); -zc9=n<5
return query.list(); z^}T=
$&
} 0yAvAx
Jz:d\M~j5
/* (non-Javadoc) s977k2pp-
* @see com.adt.dao.UserDAO#getUserCount() W11_MTIU
*/ 2U|Nkm
publicint getUserCount()throws HibernateException { *GRhZ~U
int count = 0; Ju+@ROZ
String querySentence = "SELECT count(*) FROM G0]q(.sOy
8%
1hfj
user in class com.adt.po.User"; ~01rc
Query query = getSession().createQuery ~ xf9
ml
HNU[W8mg8
(querySentence); c}v:X
Slh7
count = ((Integer)query.iterate().next S8"X7\d{
b55|JWfC`
()).intValue(); 6Mk@,\1
return count; w0*6GCP
} 8 (.<
#C>pA<YJzK
/* (non-Javadoc) `GPK$ue
* @see com.adt.dao.UserDAO#getUserByPage Qr0JJoHT
JxD@y}ZYE
(org.flyware.util.page.Page) XkdNWR0
*/ $AsM 9D<BE
publicList getUserByPage(Page page)throws 3\D jV2t
5>A3;P
HibernateException { 7ky(g'
String querySentence = "FROM user in class ix!u#7
1Kc*MS
com.adt.po.User"; qM1$?U
Query query = getSession().createQuery Iv/yIS
`+zr PpX
(querySentence);
uft~+w
P
query.setFirstResult(page.getBeginIndex()) P'Y8
t
.setMaxResults(page.getEveryPage()); @KS:d\l}U
return query.list(); ;WGY)=-gv
} jsez$m%vs
l0Pg`wH,
} u:,B"!
0|GxOzNd
:K8T\
,Y!T!o}1
~s5Sk#.z5
至此,一个完整的分页程序完成。前台的只需要调用 m,up37-{
%eT/:I
userManager.listUser(page)即可得到一个Page对象和结果集对象 x!YfZ*
cPS!%?}I
的综合体,而传入的参数page对象则可以由前台传入,如果用 7B&nV92S
Ip2JzE
webwork,甚至可以直接在配置文件中指定。 YKM(qh2
~Kb(`Px@
下面给出一个webwork调用示例: =G=.THRUk
java代码: i:[B#|%
d1E~H]X4
9d2$F9]:o
/*Created on 2005-6-17*/ ORHC bw9
package com.adt.action.user; d!wd,Xj}
eq4<
import java.util.List; e |4jT7L}
hF2
G{{8A
import org.apache.commons.logging.Log; =lDmP|^
import org.apache.commons.logging.LogFactory; vNtbb]')m
import org.flyware.util.page.Page; +ZZiZ&y
ZcdS?Z2k
import com.adt.bo.Result; 3G>E>yJ
import com.adt.service.UserService; ^WD[>E~
import com.opensymphony.xwork.Action; =3J~Fk
A6UtpyS*'
/** 7NXT.E~2
* @author Joa GzR;`,_O/
*/ ]\3dJ^q|%
publicclass ListUser implementsAction{ iySmNI
zzW^AvR
privatestaticfinal Log logger = LogFactory.getLog #Ta@A~.L
d+^4;Hv4
(ListUser.class); Jhut>8
XM=`(e
o
private UserService userService; nwkhGQ
P4N{lQ.>
private Page page; !.w S+
f9\7v_
privateList users; E=x\f "Z
H+: $ 7;
/* 5?I]\Tb
* (non-Javadoc) Icr'l$PE
* QR8F'7S
* @see com.opensymphony.xwork.Action#execute() d5],O48A
*/ .g|pgFM?
publicString execute()throwsException{ om/gk4S2
Result result = userService.listUser(page); hB^"GYZ
page = result.getPage(); f'.yM*
users = result.getContent(); b<7.^
return SUCCESS; RI%l& Hm
} $jntT(V
{Rz`)qqE
/** O'mX7rY<<(
* @return Returns the page. eVlI:yqppj
*/ %-SP
public Page getPage(){ +_ G'FD
return page; M1g|m|H7
} woR)E0'qx
4t+88e
/** Df4n9m}E
* @return Returns the users. !C+25vup
*/ Nyo6R9^
publicList getUsers(){ P&SR;{:y
return users; @Ab<I
} 0FW=8hFp,
Fb}9cpz{
/** R.fRQ>rI
* @param page npe*A
* The page to set. 5QT9
*/ kOc'@;_O
publicvoid setPage(Page page){ yZ P+
this.page = page; Ay_<?F+&
} 4 IHl'*D[#
vSyN_ AB?$
/** duqu}*Jw
* @param users N ;hq
* The users to set. @s[bRp`gd
*/ - Z|1@s&
publicvoid setUsers(List users){ f Xq e7[
this.users = users; 61KJ(
rSX3
} }1>a 71
WU\):n
/** \\T
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* @param userService S%4hv*_c
* The userService to set. n/6A@C
*/ (= \P|iv
publicvoid setUserService(UserService userService){ A<Na,EC
this.userService = userService; -OHG1"/
} /U`"|3
} ?|L)!LYx
.xD-eWw3R
;F:(5GBi
y>o#Hq&qM
COT;KC6
n
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, GphG/C (
&sKYO<6K}
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 '=ZE*nGC
v#X? KqD
么只需要: sM4wh_lO
java代码: 9}\T?6?8pX
6lhVwgy3A
[DE8s[i-
<?xml version="1.0"?> +:t1P V;l
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork hb_Ia]b
RWoiV10
1.0//EN" "http://www.opensymphony.com/xwork/xwork- x O)nS _I
7}#vANm
1.0.dtd">
78Gvc~j
%iGME%oXr
<xwork> e9:l
$`Ou *
<package name="user" extends="webwork- {L+?n*;CA
l(`w]=t&
interceptors"> bT;C8i4b\H
J^W.TM&q$,
<!-- The default interceptor stack name 1idEm*3&(
9-@w(kMu
--> tQ/w\6{
<default-interceptor-ref mI.*b(Irp
@-m&X2J+c
name="myDefaultWebStack"/> -8o8lz
JE j+>
<action name="listUser" J+;.t&5R
F3qi$ 3HM
class="com.adt.action.user.ListUser"> !9!Ns(vUM
<param (;n|>l?*
@M,_mX
name="page.everyPage">10</param> 87HVD Di
<result 15zL,yo
mrJQB I+
name="success">/user/user_list.jsp</result> 5P! ZJ3C
</action> m}XI?[!s
XJlun l)(K
</package> Jd%#eD*k9
kgQEg)A]!x
</xwork> \<PW_'6
6^zv:C%
LJiMtqg
)O}x&@Q
Gzs x0%`)
'`RCNk5l
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 e88JT_zrO
/M#A[tZ3
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。 '*T7tl
s<5t}{x
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 prwyP
C*KRu`t
_Y0o\0B
>Z3}WMgBN
1|gEY;Ru
我写的一个用于分页的类,用了泛型了,hoho &&m%=i.qK
,wq.C6;&
java代码: `@`CZg
('gjfl
MAR;k?d
package com.intokr.util; :+;F" _
pymT-
import java.util.List; :l6sESr
rdC(+2+Ay
/** R=IeAuZR4k
* 用于分页的类<br> w@"|S_E
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 'rg$%M*(
* 9<Bf5d
* @version 0.01 kL&^/([9
* @author cheng v/^2K,[0>
*/ y /PEm)=Tt
public class Paginator<E> { n3)g{K^
privateint count = 0; // 总记录数 Z^h4%o-l{
privateint p = 1; // 页编号 $zdJ\UX
privateint num = 20; // 每页的记录数 J>+Dv?Ni$
privateList<E> results = null; // 结果 gy>2=d
fkx
9I m4
/** 2L,e\]2Z
* 结果总数 Z|7Y1W[
*/ "+rX*~
publicint getCount(){ Vb1@JC9b
return count; O@ "6)/
} jeJGxfi i
O<+C$J|
publicvoid setCount(int count){ _h.[I8xgYG
this.count = count; eLt6Hg)s`9
} 1LE8,Gm&
E7*]t_p"
/** FV^kOz
* 本结果所在的页码,从1开始
e%qMrR
* G?[#<W@+
* @return Returns the pageNo. ufm#H#n)#X
*/ ;%%=G;b9
publicint getP(){ 8RocObY_W
return p; r`
3)sc
} 3)T5}_
uxR_(~8
/** e0hT
* if(p<=0) p=1 mG2}JWA
* +)V6"XY-(
* @param p 3w0m:~KS6V
*/ }XAoMp
publicvoid setP(int p){ ^ i\zMMR
if(p <= 0) sd=i!r)ya
p = 1; gz$=\=%>RL
this.p = p; nGP>M#F
} XL"e<P;t
?$o8=h
/** Jw86P=
* 每页记录数量 2x`#
f0[
*/ m=n
V$H
publicint getNum(){ l,d8%\
return num; ZkK +?:9
} Ru
sa
&#[
ZLO_5#<
/** W58\V
* if(num<1) num=1 Xe%n.DW m
*/ 8HWY]:|oh
publicvoid setNum(int num){ Ds-%\@p
if(num < 1) 9J1&g(?>-
num = 1; U2K>\/ -~
this.num = num; *rqih_j0
} )\s:.<?EQ
Y[pGaiN:
/** pM4 j=F
* 获得总页数 2
OGg`1XX
*/ '9b<r7\@
publicint getPageNum(){ 3nG(z>
return(count - 1) / num + 1; b9:E0/6
} zg^5cHP\
v[~ U*#i
/** wlkS+$<
* 获得本页的开始编号,为 (p-1)*num+1 m2 OP=z@)
*/ Ot/Y?=j~
publicint getStart(){ i/WYjo
return(p - 1) * num + 1; D'</eJ
} #$#{QEh0}
mDo]5 i<
/** ?B[Z9Ef"8l
* @return Returns the results. / P{f#rV5
*/ /.}&yRR
publicList<E> getResults(){ 5#iv[c
return results; MEo+S
} Ib!`ChZ
!.F`8OD`u
public void setResults(List<E> results){ (D))?jnC
this.results = results; AJq'~fC;I
} 8mMrGf[Q\
H,?AaM[V
public String toString(){ 3J@#V '
StringBuilder buff = new StringBuilder IoA"e@~t
ofN|%g /
(); AU)Qk$c
buff.append("{"); &;,w})
buff.append("count:").append(count); O/Da8#S<
buff.append(",p:").append(p); <iL+/^#
buff.append(",nump:").append(num); m-;u]X=a
buff.append(",results:").append B-Fu/n
n /rQ*hr
(results); mWO=(}Fb\
buff.append("}"); w8>p[F5`O
return buff.toString(); -BB 5bsjA
} JSO>rpO
dmf~w_(7
} N=|w]t0*yc
whvM^
agt7b@-5=