Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ^HuB40
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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 l LBzY`j
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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 ;5T}@4m|r
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分页支持类: nHF~a?|FT
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java代码: 211T}a
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package com.javaeye.common.util; Bz%wV-
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import java.util.List; _ q>|pt.W
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publicclass PaginationSupport { ]w4?OK(j
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publicfinalstaticint PAGESIZE = 30; CZy3]O"qW
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privateint pageSize = PAGESIZE; '4M; ;sKW
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privateList items; y5^OD63s
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privateint totalCount; #tw_`yh
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privateint[] indexes = newint[0]; QWt3KW8)
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privateint startIndex = 0; Ll#W:~
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public PaginationSupport(List items, int xd"+ &YT
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totalCount){ ?V~vP%1
setPageSize(PAGESIZE); ) 3f\H
setTotalCount(totalCount); q^ &r<i
setItems(items); z/WGL
setStartIndex(0); X -=M>H^
} c|k(_#\B
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public PaginationSupport(List items, int VKlC`k8L
7GErh,
totalCount, int startIndex){ `6# s+JA[
setPageSize(PAGESIZE); BbL]0i
setTotalCount(totalCount); GZuWAa
setItems(items); BT$Oh4y4
setStartIndex(startIndex); KP>1%ap6
} 2r+nr
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public PaginationSupport(List items, int '|Lv-7
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totalCount, int pageSize, int startIndex){ g "c7$
setPageSize(pageSize); H,7!"!?@N
setTotalCount(totalCount); (_3'nFg
setItems(items); wQ9@
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setStartIndex(startIndex); LZ&I<ID`-
} udc9KuR@
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publicList getItems(){ ^LXsU]
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return items; 3Tw9Uc\vT
} XVo+ <&
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publicvoid setItems(List items){ (4C)]
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this.items = items; 0xvSi9
} bJ6H6D>
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publicint getPageSize(){ Fo~q35uB
return pageSize; $S2
/*
} F~OQ'59!Pf
@`^Z5n.4
publicvoid setPageSize(int pageSize){ *mYGs )|
this.pageSize = pageSize; -QBM^L
} ,C_MB1u
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publicint getTotalCount(){ OJM2t`}_t
return totalCount; &5B/>ag1!
} Are0Nj&?
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publicvoid setTotalCount(int totalCount){ n!Y}D:6c6
if(totalCount > 0){ xbHI4A"Z
this.totalCount = totalCount; hKnV=Ha(
int count = totalCount / !tx.2m*5
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pageSize; ![]6| G&
if(totalCount % pageSize > 0) bwszfPM
count++; 1>2
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indexes = newint[count]; S&'s/jB
for(int i = 0; i < count; i++){ ^'+#BPo9@
indexes = pageSize * %@q2
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i;
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} vI48*&]wTf
}else{ ^R(=4%8%"
this.totalCount = 0; $?[pcgv
} )U]q{0`
} D)S_ p&
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publicint[] getIndexes(){ _t4(H))]vG
return indexes; 0r!F]Rm-^
} p`52
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publicvoid setIndexes(int[] indexes){ '[_.mx|cd`
this.indexes = indexes; FBzsM7]j
} VOg'_#I
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publicint getStartIndex(){ V;Ln|._/t
return startIndex; [`bK {Dq2
} E2`9H-6e
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publicvoid setStartIndex(int startIndex){ )}_}D+2
if(totalCount <= 0) l>(*bb1}b
this.startIndex = 0; #%#N.tB5
elseif(startIndex >= totalCount) {CTJX2&
this.startIndex = indexes ?UeV5<TewS
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[indexes.length - 1]; q,;wD1_wG
elseif(startIndex < 0) |}X[Yg=FG
this.startIndex = 0; ;.R)
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else{ WK#%G
this.startIndex = indexes 9gIim
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[startIndex / pageSize]; E4_,EeC#
} cw0uLMqr`
} DC_k0VBn
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publicint getNextIndex(){ LA/Qm/T
int nextIndex = getStartIndex() + :vaVghN\
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pageSize; fZnq5rTk"
if(nextIndex >= totalCount) Jv]$@>#
return getStartIndex(); wqzpFPk(
else ;W\?lGOs{
return nextIndex; (_gt!i{h
} Y\4B2:Qd9
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publicint getPreviousIndex(){ 2)QZYgfh
int previousIndex = getStartIndex() - 5rQu^6&
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pageSize; uy<b5.!-
if(previousIndex < 0) G2P:|R
return0; TDy$Mv=y
else t/3qD7L
return previousIndex; 0&tr3!h\
} yDRi
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} ,*m|Lt%;R
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抽象业务类 :wUi&xw
java代码: 8 ~Pdr]5
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/** O]!o|w(
* Created on 2005-7-12 'UuHyC2Ha3
*/ E!L_"GW
package com.javaeye.common.business; J5xZLv
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import java.io.Serializable; X7tBpyi
import java.util.List; tv:
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import org.hibernate.Criteria; #n|eq{fkK
import org.hibernate.HibernateException; h$%h w+"4
import org.hibernate.Session; Ya!PV&"Z
import org.hibernate.criterion.DetachedCriteria; 'tX}6wurf
import org.hibernate.criterion.Projections; mSk";UCn
import WQBV~.<Yv
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org.springframework.orm.hibernate3.HibernateCallback; xNLgcb@v>
import Jq8v69fyQ
8{6`?qst@
org.springframework.orm.hibernate3.support.HibernateDaoS eIhfhz?Q;#
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upport; !>GDp >0
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import com.javaeye.common.util.PaginationSupport; K @:t6
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public abstract class AbstractManager extends pP#|: %
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HibernateDaoSupport { kD)]\
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privateboolean cacheQueries = false; sJ5#T iX
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privateString queryCacheRegion; 15Jc PDV
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publicvoid setCacheQueries(boolean J'k^(ZZ
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cacheQueries){ tOo\s&j
this.cacheQueries = cacheQueries; S?c<Lf~W
} f=7[GZoDn
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publicvoid setQueryCacheRegion(String 3[ xHY@c
/R>YDout}
queryCacheRegion){ ~4mRm!DP
this.queryCacheRegion = UoSc<h|
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queryCacheRegion; joNV4v"=`
} >Qg-dJt[
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publicvoid save(finalObject entity){ 1Cw$^jd
getHibernateTemplate().save(entity); q &S@\b
} O2U}jHsd
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publicvoid persist(finalObject entity){ b%d, X-3
getHibernateTemplate().save(entity); `v'yGsIV
} ^E~1%Md.
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publicvoid update(finalObject entity){ e-VGJxR
getHibernateTemplate().update(entity); 7=&+0@R#/d
} 0}'/3Q
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publicvoid delete(finalObject entity){ HC6v#-( `{
getHibernateTemplate().delete(entity); T#vY(d
} Rv.IHSQUo
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publicObject load(finalClass entity, u}rJqZ
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finalSerializable id){ ;3%Y@FS@
return getHibernateTemplate().load MIN}5kc<
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(entity, id); i8%@4U/ J
} sI{?4k
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publicObject get(finalClass entity, _3#_6>=M
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finalSerializable id){ SQ'%a-Mct
return getHibernateTemplate().get 9 aK U}y
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(entity, id); '+c@U~d*7
} D<WGau2H
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publicList findAll(finalClass entity){ (Bv~6tj~J
return getHibernateTemplate().find("from [/<kPi
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" + entity.getName()); <Ynrw4[)t
} ~n(LBA
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publicList findByNamedQuery(finalString $FZcvo3@*S
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namedQuery){ ^/xb-tuV
return getHibernateTemplate @xk ;]H80
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().findByNamedQuery(namedQuery); |qU~({=b
} 43~v1pf{!
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publicList findByNamedQuery(finalString query, <UTO\w%
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finalObject parameter){ 1qp"D_h
return getHibernateTemplate J*AYZS-tSE
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().findByNamedQuery(query, parameter); \!%~(FM
} +k0UVZZX?
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publicList findByNamedQuery(finalString query, h${=gSJc
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finalObject[] parameters){ ^g.HJQ'vF
return getHibernateTemplate [@]i_L[
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().findByNamedQuery(query, parameters); 1@F>E;YjL=
} X?(R!=a
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publicList find(finalString query){ F;Q'R|HQ
return getHibernateTemplate().find !P":z0K4
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(query); /J(~NGT
} ;1>V7+/
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publicList find(finalString query, finalObject OM`Ws5W}f
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parameter){ Dr"PS
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return getHibernateTemplate().find H29vuGQjq
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(query, parameter); k ,ezB+
} iRM ?_|
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public PaginationSupport findPageByCriteria ?=HoU3
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(final DetachedCriteria detachedCriteria){ p4$4;)
return findPageByCriteria `7.$
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); phwBil-vUU
} t@iw&>8z
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public PaginationSupport findPageByCriteria nj-LG!"a
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(final DetachedCriteria detachedCriteria, finalint Q@"!uB.e
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startIndex){ !LsIHDs4
return findPageByCriteria R~;8v1>K
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(detachedCriteria, PaginationSupport.PAGESIZE, ke)<E98DC
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startIndex); N{6-a
} Q<yvpT(
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public PaginationSupport findPageByCriteria >D_)z/v?"
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(final DetachedCriteria detachedCriteria, finalint aPX'CG4m
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pageSize, j!@,r^(
finalint startIndex){ `H9!Z$7G
return(PaginationSupport) OU*skc>
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getHibernateTemplate().execute(new HibernateCallback(){ mILCC}Kt
publicObject doInHibernate
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(Session session)throws HibernateException { 8:Dkf v
Criteria criteria = V}FH5z
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detachedCriteria.getExecutableCriteria(session); <)"2rxX&5
int totalCount = *z dUCX
n-1
((Integer) criteria.setProjection(Projections.rowCount a%QgL&_5
anORoK.
()).uniqueResult()).intValue(); u]]mbER*t#
criteria.setProjection M[e^Z}w.V
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(null); gj&5>brP
List items = +;bZ(_ohG
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criteria.setFirstResult(startIndex).setMaxResults 'CRjd~L
-67!u;
(pageSize).list(); 3@1$y`SN
PaginationSupport ps = X<f4X"y
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new PaginationSupport(items, totalCount, pageSize, n} ]gAX
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startIndex); m]}EVa_I`/
return ps; pezfB{x?
} {J/+KK
}, true); ]1I-e2Q-J
} OUN"'p%%
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public List findAllByCriteria(final }|RL6p-/'
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DetachedCriteria detachedCriteria){ l(}l([rdQ
return(List) getHibernateTemplate K1o&(;l8G
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().execute(new HibernateCallback(){ :zpT Gk8Z
publicObject doInHibernate M"$g*j
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(Session session)throws HibernateException { LCb0Kq}*/(
Criteria criteria = +^.xLTX`$
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detachedCriteria.getExecutableCriteria(session); L\"eE'A
return criteria.list(); {#&D=7LP
} fr8';Jm
}, true); @[Wf!8_
}
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public int getCountByCriteria(final hK3Twzte
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DetachedCriteria detachedCriteria){ 7(H?3)%0
Integer count = (Integer) SE$l,Z"[*b
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getHibernateTemplate().execute(new HibernateCallback(){ AR
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publicObject doInHibernate |Vp
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(Session session)throws HibernateException { zY].ZS=7
Criteria criteria = .mxc~
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detachedCriteria.getExecutableCriteria(session); cu#r#0U-
return CYM>4C~>JW
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criteria.setProjection(Projections.rowCount 6 I43a1[s
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()).uniqueResult(); R0F&!y!B
} *~.'lE%[U
}, true); ~x J#NC+
return count.intValue(); CU/Id`"tW
} 1`Uu;mz
} WISK-z
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用户在web层构造查询条件detachedCriteria,和可选的 g$z6*bL
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 G%CS1#
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PaginationSupport的实例ps。 <B+
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ps.getItems()得到已分页好的结果集 WGUd@lC~
ps.getIndexes()得到分页索引的数组 HLqDI lL
ps.getTotalCount()得到总结果数 lEw!H^O4
ps.getStartIndex()当前分页索引 |w>d]eA5
ps.getNextIndex()下一页索引 '1Ex{$Yk
ps.getPreviousIndex()上一页索引 $`L
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 On,z#A
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 NkAu<>
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一下代码重构了。 `U>]*D68
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我把原本我的做法也提供出来供大家讨论吧: cHnd
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首先,为了实现分页查询,我封装了一个Page类: A|m0.'/
java代码: QjTs$#eMW
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/*Created on 2005-4-14*/ $wk(4W8E
package org.flyware.util.page; R l)g[s
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/** :S+Bu*OyH
* @author Joa I"D}amuv
* ;20sh^~
*/ JRDIGS_~
publicclass Page { c7R6.T
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/** imply if the page has previous page */ ] B>.}
privateboolean hasPrePage; ~hT(uxU/
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/** imply if the page has next page */ )\{]4[9N
privateboolean hasNextPage; `Zci<
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/** the number of every page */ C0&ZQvvy1:
privateint everyPage; Z|d+1i
#_: %Yd
/** the total page number */ A!a.,{fZ
privateint totalPage; Xzqx8Kd
mC'<Ov<eJ
/** the number of current page */ v/,,z+%-
privateint currentPage; "[CR5q9Pr
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/** the begin index of the records by the current &E-q(3-
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query */ :7s2M
privateint beginIndex; B06W(y,3Q>
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/** The default constructor */ `X(H,Q}*;
public Page(){ !_-Uwg
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} MwaRwk;
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/** construct the page by everyPage 3.h0
* @param everyPage m ~gc c
* */ X#ud_+6x
public Page(int everyPage){ B_"PFWwg
this.everyPage = everyPage; |J~A )Bw?
} +)_#j/
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/** The whole constructor */ lr)9 U7
public Page(boolean hasPrePage, boolean hasNextPage, cvjZ$Fcc%(
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int everyPage, int totalPage, ksyQ_4^SO
int currentPage, int beginIndex){ pV$A?b"?*
this.hasPrePage = hasPrePage; <'~6L#>,<
this.hasNextPage = hasNextPage; "7w=LhzV[$
this.everyPage = everyPage; WdbHT|.Aj
this.totalPage = totalPage; [f]:hJi
this.currentPage = currentPage; !j9(%,PR
this.beginIndex = beginIndex; 88l{M[B2
} p\tA&>3-
.+5;AtN
/** hSaw)g`w
* @return CJ6v S
* Returns the beginIndex. %U9f`qE
*/ fbJa$
publicint getBeginIndex(){ Eg1|Kg\&
return beginIndex; )IKqO:@
} zT'(I6S:)
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/** ;33SUgX
* @param beginIndex J>fq5
* The beginIndex to set. CT(HTu
*/ Wli!s~c5Fo
publicvoid setBeginIndex(int beginIndex){ m(CsO|pz
this.beginIndex = beginIndex; (w
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} ^j2z\yo
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/** "P$')uwE
* @return
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* Returns the currentPage. fH%C&xj'&
*/ ,W>-MPJn[8
publicint getCurrentPage(){ $I9U.~*
return currentPage; [2ri=lf,
} ;VbB]aUg
}*7Gq
/** 3w+ +F@(
* @param currentPage DO~~
* The currentPage to set. 7Kti&T
*/ a)!R4
publicvoid setCurrentPage(int currentPage){ *]ME]2qP
this.currentPage = currentPage; 8x9;3{R
} #y1M1O g
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/** UFeQ%oRa8
* @return }U**)"
* Returns the everyPage. )a$sx}
*/ H:o=gP60]
publicint getEveryPage(){ /.(F\2+A
return everyPage; FmQiy+.|
} QG09=GQ
T )bMHk
/** x/%/MFK)>8
* @param everyPage Srrzj-9^)K
* The everyPage to set. tNxKpA |F
*/ v5.KCc}"
publicvoid setEveryPage(int everyPage){ ?Xqkf>
this.everyPage = everyPage; 'N/u<`)
} _w7yfZLv+
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/** }L>0}H
* @return Q1x=@lXR
* Returns the hasNextPage. 3&B- w
*/ (>gb9n
publicboolean getHasNextPage(){ <M\#7.](
return hasNextPage; @y,>cDg
} #W/ATsDt
jr^btVOI#\
/** /=KEM gI?
* @param hasNextPage K%;=i2:
* The hasNextPage to set. AdRK )L
*/ ephvvj~zW4
publicvoid setHasNextPage(boolean hasNextPage){ &Vg)/t;
this.hasNextPage = hasNextPage; [2z
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} 8aW<lu
>&Vz/0
/** Y7 e1%,$v
* @return \sS0@gnDI
* Returns the hasPrePage. D`)K3;h
*/ #X0Y8:vj
publicboolean getHasPrePage(){ 1c4:'0
return hasPrePage; %5j*e
} 2QKt.a
z!)@`?
/** E+Dcw
* @param hasPrePage 9M@,BXOt
* The hasPrePage to set. x(A6RRh
*/ {Bb:\N8X
publicvoid setHasPrePage(boolean hasPrePage){ 2FEi-m}
this.hasPrePage = hasPrePage; w+hpi5OH
} [f=Y*=u9,
1/c+ug!y
/** %ejq|i7
* @return Returns the totalPage. K/8TwB?I
* 4 Z&KR<2Z
*/ seZb;0
publicint getTotalPage(){ ^_uCSA'X
return totalPage; E*QLw*H
} SxL/]jWR7
:13u{5:th
/** V/yj.aA*@
* @param totalPage Sea6xGdq
* The totalPage to set. Nu+DVIM
*/ z]!w@:
publicvoid setTotalPage(int totalPage){ rf]x5%ij
this.totalPage = totalPage; rg I Z
} |]b,% ?,U
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} >*$Xbj*
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vHb^@z=
[iC]Wh%
.L.9e#?3
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 ?B<.d8i
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个PageUtil,负责对Page对象进行构造: f\H1$q\p\
java代码: 4j<[3~:0
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/*Created on 2005-4-14*/ l$m}aQ%h
package org.flyware.util.page; 7hT@,|(j
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import org.apache.commons.logging.Log; j)#GoU=w
import org.apache.commons.logging.LogFactory; D{JwZL@7k2
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/** =:\5*
* @author Joa ]N:Wt2
* E|W7IgS
*/ dEam|
publicclass PageUtil { FhQb9\g
j? Vs"d|
privatestaticfinal Log logger = LogFactory.getLog 'a>D+A:
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(PageUtil.class); SUD~@]N1
:)%cL8Nz]$
/** kR{$&cE^
* Use the origin page to create a new page '30JJ0
* @param page w^}*<q\
* @param totalRecords 2%)~E50U
* @return sY?sQ'E2]
*/ =]1g*~%
publicstatic Page createPage(Page page, int Ho $+[K
kH4m6p
totalRecords){ fr&p0)85>B
return createPage(page.getEveryPage(), lHE+o;-
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page.getCurrentPage(), totalRecords); 3V<c4'O\W
} 2m9qg-W
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/** /buj(/q^#
* the basic page utils not including exception nPH\Lra
$9Gra#
handler !(y(6u#
* @param everyPage Bf" ZmG9
* @param currentPage SBY0L.
* @param totalRecords ^!x qOp!
* @return page n%!50E6*:
*/ 1yTw*vH F
publicstatic Page createPage(int everyPage, int T#HF!GH]
.`oKd@I*"
currentPage, int totalRecords){ j?VHR$
everyPage = getEveryPage(everyPage); Ii>#9>!F
currentPage = getCurrentPage(currentPage); }d@;]cps
int beginIndex = getBeginIndex(everyPage, S`vw<u4t
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currentPage); V>ZDJW"G!
int totalPage = getTotalPage(everyPage, rw?wlBEG%
8yM8O
#S
totalRecords); ?F~0\T,7
boolean hasNextPage = hasNextPage(currentPage, jH<,dG:{
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totalPage); (@S9>z4s
boolean hasPrePage = hasPrePage(currentPage); |I3&a=,
,<[x9 "3\
returnnew Page(hasPrePage, hasNextPage, (U:6vk3Q
everyPage, totalPage,
n,{
currentPage, ${`q!
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beginIndex); ){w!<Lb
} a&[>kO
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privatestaticint getEveryPage(int everyPage){ y|3!E>Up
return everyPage == 0 ? 10 : everyPage; Pt'=_^Io
} 2L=(-CH9]
\!k\%j9
privatestaticint getCurrentPage(int currentPage){ A@reIt
return currentPage == 0 ? 1 : currentPage; ?28)l
4 Ml
} In*0.
{fMo#`9=
privatestaticint getBeginIndex(int everyPage, int =.,XJIw&
:)Da^V
currentPage){ Me^L%%:@
return(currentPage - 1) * everyPage; =q[ynZ8O\w
} 1"T&B0G3l
B0^:nYko
privatestaticint getTotalPage(int everyPage, int w<Iq:3
?S.LGc
totalRecords){ ~xc0Ky?8
int totalPage = 0; ~!_UDD
-#g0
if(totalRecords % everyPage == 0) .[Ny(X/]/}
totalPage = totalRecords / everyPage; >Fc=F#tA9
else {7K l#b
totalPage = totalRecords / everyPage + 1 ; 8qT^=K
$
<g, 21(bc
return totalPage; 51'V[tI;8
} LtNspFoLb
EpENhC0
privatestaticboolean hasPrePage(int currentPage){ vb`:
return currentPage == 1 ? false : true; /}s#
} $[b1_Db
dCzS f4:
privatestaticboolean hasNextPage(int currentPage, D?"Q)kVuD
uFaT~ 4
int totalPage){ X$ A ]7t
return currentPage == totalPage || totalPage == K:Z|# i-
ca%XA|_J
0 ? false : true; EDg; s-T=
} >,f5 5
Ex{;&UWm
Qk&6Z%
} &]c7<=`K"
s2K8|q=
7s;*vd>
$-gRD|oY
VC^QCuSq
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 S4{\5ulr7
\G6V -W
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 +Xmza8T9
3GZrVhU?m
做法如下: MED_#OS
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a(x#6
T=fVD8
的信息,和一个结果集List: Vtk}>I@%
java代码: Y7`Dx'x
_Fjax
(KR.dxzjf
/*Created on 2005-6-13*/ q&,uJo
package com.adt.bo; ;$UB@)7%
qx}*L'xB
import java.util.List; oSP^
.BJ$
?q"9ZYX<
import org.flyware.util.page.Page; KzB9
mMrO
bbWW|PtWwP
/** W}k)5<C4v
* @author Joa 1["IT.,f.
*/ 'he&h4fm
publicclass Result { x!UGLL]_M
&tw{d DD6
private Page page; dVBr-+
/-g%IeF
private List content; ;AT~?o`n
ts=+k/Z
/** K?V'
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* The default constructor wA6<BujD
*/ weIlWxy
public Result(){ )lVplAhZD
super(); smX&B,&@
} 7] 17?s]t,
WQHlf0]
/** vFK(Dx
* The constructor using fields 1(4IcIR5T;
* N'8}5Kx5
* @param page 8FBXdk?A
* @param content wQX%*GbL2
*/ 0f,Ii_k bT
public Result(Page page, List content){ <:~'s]`zf
this.page = page; d'p@[1/
this.content = content; nAyyjd3!S
} HE3x0H}o>
ra{HlB{
/** >orDw3xC
* @return Returns the content. {^Q1b.=
*/ xQ8?"K;iX
publicList getContent(){ \eS-wO7%
return content; _({K6adb
} 0EUC8Ni
'>UQsAvm
/** PL7_j
* @return Returns the page. Yn-;+ 4 K
*/ |A:+[35
public Page getPage(){ "@&I*1&
return page; g=kuM
} L(3}
H,t
9jrlB0
/** IaRq6=[
* @param content 50`<[w<J
q
* The content to set. FdmoR;
*/ )>WSuf
j
public void setContent(List content){ %<'PSri
this.content = content; N x/_+JWje
} ]a\HgFp@
!*=+E%7
/** 1.q
a//'RW
* @param page %;YERO!
* The page to set. @4j!M1}4
*/ :JG2xtn
publicvoid setPage(Page page){ YDiru
this.page = page; hkR Jqta)
} q=uJ^N
} qISzn04
?r(Bu
wfBf&Z0{
LF_am*F
N`!=z++G
2. 编写业务逻辑接口,并实现它(UserManager, Rs1JCP=d8
"\x\P)j0>
UserManagerImpl) 2]-xmS>|b
java代码: Z$ Mc{
Tg#%5~IX
2ee((vO&
/*Created on 2005-7-15*/ x'`L(C
package com.adt.service; t+O7dZt%r
-hpMd/F
import net.sf.hibernate.HibernateException; 1$rrfg
2W=am_\0e.
import org.flyware.util.page.Page; atjrn:X
YDo,9
import com.adt.bo.Result; EyPF'|Qtn
J l9w/T
/** p+|(lrYC
* @author Joa Lw #vHNf6
*/ aG/L'weR
publicinterface UserManager { aT%6d@g
bY7~b/
public Result listUser(Page page)throws \J3n[6;
K@+(6\6I
HibernateException; rJ_fg$.<
'5m`[S-IU
} 'Lv>!s 7
/,#&Htk
:TN^}RML
p+d?k"WN?
k6W
[//
java代码: pbb6?R,
F5;x>;r
<ooRpn
/*Created on 2005-7-15*/ *[[TDduh&
package com.adt.service.impl; <)$b=z
!Typ_Cs
import java.util.List; vaUUesytt
0`l(c
import net.sf.hibernate.HibernateException; 'CO3b,
Qg4g(0E@
import org.flyware.util.page.Page; @+
U++
import org.flyware.util.page.PageUtil; yW)X
asn
h"5!puN+
import com.adt.bo.Result; b py576GwA
import com.adt.dao.UserDAO; YkbZ 2J*-
import com.adt.exception.ObjectNotFoundException; (xhV>hsA
import com.adt.service.UserManager; dGBVkb4]T
>J
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/** 7e
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* @author Joa 9a0ibN6m
*/ d 1bx5U
publicclass UserManagerImpl implements UserManager { #-Nc1+gu
>@NGX-gp
private UserDAO userDAO; EkE U}2
pUXszPf
/** b(.,Ex]
* @param userDAO The userDAO to set. vx8-~Oq{|;
*/ .ITR3]$
publicvoid setUserDAO(UserDAO userDAO){ nPS:T|*G
this.userDAO = userDAO; p[lciWEW
} V57tn6>b
QUU'/e2^c
/* (non-Javadoc) &lYe
* @see com.adt.service.UserManager#listUser *wetPt)~v_
j9Y'HU5"
(org.flyware.util.page.Page) &DgJu.
*/ qCaM]Y
public Result listUser(Page page)throws kan4P@XVS
m6=Jp<
HibernateException, ObjectNotFoundException { ^-i<TJ
int totalRecords = userDAO.getUserCount(); />\6_kT
if(totalRecords == 0) K<Qy1y~[
throw new ObjectNotFoundException >*aqYNft
9F^rXY.
("userNotExist"); El)WjcmH
page = PageUtil.createPage(page, totalRecords); G*lkVQ6?
List users = userDAO.getUserByPage(page); SYsbe 5j
returnnew Result(page, users); !Cv:,q
} I>L@P`d
Lw!Q*3c
} 79JU
f.&((z?rC
Pwh0Se5Z
9:tn!<^=I
V
K)%Us-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 o1(?j}:c|
(jY -MF3
询,接下来编写UserDAO的代码: ,:1_I`d>#X
3. UserDAO 和 UserDAOImpl: E)=X8y
java代码: bAa+MB#A
^E3 i]Oem
Y]R;>E5o|
/*Created on 2005-7-15*/
3l8k O
package com.adt.dao; z1u1%FwOfM
n!K<g.tjW
import java.util.List; {v>orP?
D7"RZF\)
import org.flyware.util.page.Page; Htu}M8/4
oTqv$IzqP
import net.sf.hibernate.HibernateException; )KPQ8y!d
Q7-d]xJ^
/** y! lEGA7
* @author Joa Os# V=P
*/ ^cy.iolt
publicinterface UserDAO extends BaseDAO { 'U"ub2j
T@ecWRro
publicList getUserByName(String name)throws uqg#(ADy?R
dUg| {l
HibernateException; GcL:plz
xJ(4RaP
publicint getUserCount()throws HibernateException; ;^K4kK&f
Mmu>&C\
publicList getUserByPage(Page page)throws LT ZoO9O
&CEZ+\bA
HibernateException; "}jY;d#n
=(x W7Pt~
} a8Q=_4
l
6GZzNhz
u(!@6%?-
J^R#
L,B#%t
java代码: &b#O=LF
))qOsphN
4x'N#m{p
/*Created on 2005-7-15*/ U%~L){<V[
package com.adt.dao.impl; [N-t6Z*
+%hA6n
import java.util.List; U[Pll~m2b
C
{GSf`D!T
import org.flyware.util.page.Page; -`o22G3w
8=#J:LeXj
import net.sf.hibernate.HibernateException; w9J^s<e
import net.sf.hibernate.Query; RI
q9wD}4(
%j3*j
import com.adt.dao.UserDAO; _m+64qG_8'
BrQXSN$i
/** 6H\apgHm
* @author Joa ?u`TX_OsB
*/ I C6}s
public class UserDAOImpl extends BaseDAOHibernateImpl ;
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&!lGx7zf
implements UserDAO { D6KYkN(,v
]ctlK'.
/* (non-Javadoc) *0
0K3
* @see com.adt.dao.UserDAO#getUserByName ?1z." &
Y0||>LX
(java.lang.String) n' \poB?
*/ FD&"k=p+X
publicList getUserByName(String name)throws l }i
.
7;UUS1
HibernateException { G:]w
UC\
String querySentence = "FROM user in class MU ;
L7^
P1Z+XRWOM
com.adt.po.User WHERE user.name=:name"; L(yR"A{FsE
Query query = getSession().createQuery UoLvc~n7
BihXYux*
(querySentence); V_&>0P{q
query.setParameter("name", name); X$L9kZ
return query.list(); \Ami-<T
} MMpGI^x!-X
jo.Sg:7&
/* (non-Javadoc) !XvQm*1
* @see com.adt.dao.UserDAO#getUserCount() Myj 68_wf
*/ 7>a-`"`O
publicint getUserCount()throws HibernateException { J 1?)z+t9~
int count = 0; PN!NB.
String querySentence = "SELECT count(*) FROM lJfn3
8}&O7zO?
user in class com.adt.po.User"; MMMuT^X
Query query = getSession().createQuery jORU+g
f\ wP}c'
(querySentence); Hvn{aLa.
count = ((Integer)query.iterate().next ^b{w\HZ
Wn(pz)+Y
()).intValue(); 4&Q.6HkL
return count; O;u&>BMk
} u'o."J^&'
VFZ_Vw
/* (non-Javadoc) a]<y*N?qu
* @see com.adt.dao.UserDAO#getUserByPage o2FQ/EIE
v>2gx1F"?
(org.flyware.util.page.Page) |G+6R-_
*/ vpoeK'bi,
publicList getUserByPage(Page page)throws c&1:H1#
qeK_w
'
HibernateException { V Q6&7@
c
String querySentence = "FROM user in class <$^76=x,8P
z*cC2+R}=
com.adt.po.User"; p*T`fOL
Query query = getSession().createQuery <5s51b <
u;fD4CA
(querySentence); T9@W,0#
query.setFirstResult(page.getBeginIndex()) &TmN^R>
.setMaxResults(page.getEveryPage()); #PzRhanX
return query.list(); p nS{W
\Q
} >AT{\W!N
E1U~ew
} A8?uCkG
&*wN@e(c
@O7hY8",
H1]An'qz,
q;dg,Om
至此,一个完整的分页程序完成。前台的只需要调用 wt;7+
*CHLs^)
userManager.listUser(page)即可得到一个Page对象和结果集对象 vjy 59m
yw|O,V<4N
的综合体,而传入的参数page对象则可以由前台传入,如果用 3x=f}SO&
<+1d'VQ2
webwork,甚至可以直接在配置文件中指定。 3|=9aM^ x^
#S57SD
下面给出一个webwork调用示例: =Fq"lq %
java代码: "t4$%7L]
k^
CFu
eIzT(3(
/*Created on 2005-6-17*/ |U*wMYC
package com.adt.action.user; !2)$lM1@J
SjT8eH #
import java.util.List; 3d qj:4[f
cxBu2(Y
import org.apache.commons.logging.Log; Hshm;\'
import org.apache.commons.logging.LogFactory; tpJe1 J<
import org.flyware.util.page.Page; &-Bw7v
mHqw,28}
import com.adt.bo.Result; 2|xNT9RW
import com.adt.service.UserService; PVGvj c
import com.opensymphony.xwork.Action; pDGX$1O"
X>Cl{.
/** B|Y6;4?
* @author Joa (mHCK5
*/ rkF]Q_'`t;
publicclass ListUser implementsAction{ |IbCN
_5F8F4QY`
privatestaticfinal Log logger = LogFactory.getLog 0XCtw6
$
e<&7
(ListUser.class); iez@j
xn49[T
private UserService userService; 3cuVyf<v
c$.h]&~dN
private Page page; H pHXt78
FSaCbs(
privateList users; ,J|8P{ZO
VTOZ#*f
/* fVlTsc|e
* (non-Javadoc) n\f8%z
* }<y-`WB
* @see com.opensymphony.xwork.Action#execute() xXpeo_y'
*/ {&_1/
publicString execute()throwsException{ ,/O,j
SRk
Result result = userService.listUser(page); Byx8`Cx1
page = result.getPage(); Gj6(ycaS
users = result.getContent(); lkNaSz[
return SUCCESS; mM| 313
} 3snr-)
D$W&6'
/** 26yjQ
* @return Returns the page. x>5"7MR`
*/ /&g5f4[|p
public Page getPage(){ P&Vqr
return page; :x*|?zII
} ^l}Esz`-M
N=e-"8
/** V87?J w%2
* @return Returns the users. ;9>(yJI+
*/ biTET|U`$
publicList getUsers(){ vs3px1Xe#
return users; Bnju_)U5)
} )Mw<e
6%/@b`vZ
/** OR4ZjogzY
* @param page R5i v]8X4W
* The page to set. 's.%rre%
*/ UZ8
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publicvoid setPage(Page page){ r;gtfX*
this.page = page; pBW|d\8
} .VFa,&5;3
t{\,vI
/** S GAu.8Js
* @param users iGG;
* The users to set. MdzG2uZT
*/ RP}.Ei
publicvoid setUsers(List users){ ?]i.Zi\[f
this.users = users; so~vnSQ!x
} 4CR.=
{0J TN%e
/** 9,h'cf`F
* @param userService [ugBVnma
* The userService to set. fmuAX w>
*/ QLx]%E\
publicvoid setUserService(UserService userService){ FBn`sS8hH
this.userService = userService; Ep/kb-~-
} [nQ<pTg~r
} N1dp%b9W(
9cJzL"yi
]s3U +t?
i
#5rk(^t
h{ s- e.
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, j7&57'
EAVB:gE
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 Tvd=EO
oz!;sj{,D
么只需要: R)s@2S
java代码: <S*o}:iB
Jg I+k Nx
5ZG-3qj
<?xml version="1.0"?> JGS4r+
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork mlolSD;7
3*13XQ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- v!oXcHK/
Dps0$fc
1.0.dtd"> J1,\Q<
M"
|Mte
<xwork> B+yr
6Q.
39s%CcI`k
<package name="user" extends="webwork- ifA{E}fRZP
yFp8 >
interceptors"> Gy*6I)l
hhu!'(j
<!-- The default interceptor stack name Isa]5>
Rk#@{_
--> F1s kI _!
<default-interceptor-ref &5Ai&<q"p
/IDfGAE
name="myDefaultWebStack"/> K1S)S8.EZ8
Z4U8~i
<action name="listUser" >L6V!
#q`-"2"|
class="com.adt.action.user.ListUser"> 1:I47/
<param Z-(V fp4
l`s_Id#
name="page.everyPage">10</param> 9Ra_[1
<result n !ty\E
L_Q1:nL-0
name="success">/user/user_list.jsp</result> 'Wv=mBEfZ
</action>
Do3;-yp>`
-\mbrbG9H
</package> wIi_d6?
2=pVX
</xwork> )*[3Imq/
^MPl
wx
Og8:
R8
1z|+c|_
|2,'QTm=
0)}bJ,5/
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ;M '?k8L
cnh\K.*}_x
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ]V!q"|
~`Q8)(y<#$
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^cO^3=
&PRu[!
<&3qFK*9r
!|P>%bi
\wY? 6#;
我写的一个用于分页的类,用了泛型了,hoho 2+pLDIIT
Gq4~9Tm)*
java代码: FyuCYg
\p
@}&o(q1M0
>mzK96
package com.intokr.util; a%2r]:?^?
K-VNU
import java.util.List; Yc+0OBH[
#`P4s>IL1
/** V9 <!pMj
* 用于分页的类<br> %zg&eFRHI
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 31b9pi}nf
* /JPyADi
* @version 0.01 "g7`Ytln
* @author cheng yw'b^D/
*/ YKbR#DC\
public class Paginator<E> { OyVdQ".
privateint count = 0; // 总记录数 1-C 2Y`
privateint p = 1; // 页编号 KL]@y!QU
privateint num = 20; // 每页的记录数 d,j"8\@
privateList<E> results = null; // 结果 |ToCRM
A!}Wpw%(/
/**
:~JgB
* 结果总数 \N1G5W
*/ (Sc]dH
publicint getCount(){ ]wLHe2bEu
return count; U#v??Sl
} [bH5UTA
j>s>i
publicvoid setCount(int count){ X^4HYm
this.count = count; M|e
Qds
} *RKYdwnb
(I~-mzu\
/** {4"!~W
* 本结果所在的页码,从1开始 nU$;W
* j*"V!d
* @return Returns the pageNo. z38&