Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 R2)@Q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (U'n1s/X
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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 <Y)14w%
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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 v/ry" W
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分页支持类: dC6>&@
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java代码: .w4|$.H
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package com.javaeye.common.util; s4Ja y!A
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import java.util.List; @JSWqi>
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publicclass PaginationSupport { $PMr)U
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publicfinalstaticint PAGESIZE = 30; 0s`6d;
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privateint pageSize = PAGESIZE; 8g=O0Gb
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privateList items; i7dDklj4
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privateint totalCount; 4b}p[9k
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privateint[] indexes = newint[0]; wQ(DX!
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privateint startIndex = 0; z_(l]Ern}
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public PaginationSupport(List items, int jO"/5x26
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totalCount){ lz=DGm
setPageSize(PAGESIZE); pKLcg"{[F
setTotalCount(totalCount); W<<G
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setItems(items); 6`9QGi,)
setStartIndex(0); D0#U*tq;
}
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ky !ZJR
public PaginationSupport(List items, int 5JOfJ$(n
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totalCount, int startIndex){ ,U9j7E<4
setPageSize(PAGESIZE); lsV>sW4]Z
setTotalCount(totalCount);
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setItems(items); t_^cqEr
setStartIndex(startIndex); _
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} Wda?$3!^q
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public PaginationSupport(List items, int gB#!g@
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totalCount, int pageSize, int startIndex){ v0r:qku
setPageSize(pageSize); C=c&.-Nb9
setTotalCount(totalCount); Cdl"TZ<
setItems(items); jGLmgJG-P
setStartIndex(startIndex); ~H''RzN
} ="T}mc
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publicList getItems(){ W[QgddR
return items; tQj=m_
} R?:K\
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publicvoid setItems(List items){ heF'7ezv#
this.items = items; -0(+a$P7e
} 2;:]Q.g
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publicint getPageSize(){ Z+R-}<
return pageSize; lxTqGwx
} je\]j-0$u
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publicvoid setPageSize(int pageSize){ e>Q:j_?.e
this.pageSize = pageSize; PJb/tKC
} f:q2JgX
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publicint getTotalCount(){ zV$Z@o
return totalCount; @ &c@
} !/2kJOSp
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publicvoid setTotalCount(int totalCount){ 2P57C;N8|
if(totalCount > 0){ 7T X$
this.totalCount = totalCount; Q-_;.xy#4
int count = totalCount / a&)$s;
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pageSize; OG IN-
if(totalCount % pageSize > 0) 0Q%I[f8
count++; eJOo~HIWQ
indexes = newint[count]; 0NsPo
for(int i = 0; i < count; i++){ )$Fw<;4
indexes = pageSize * @6 jKjI
;).QhHeg>
i; On4Vqbks
} 99h#M3@!
}else{ #r&yH^-
this.totalCount = 0; MMRO@MdfV
} w2"]%WS %
} 7<Ut/1$MI
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publicint[] getIndexes(){ :)_P7k`>e/
return indexes; Sr10ot&ox
} @ceL9#:uc
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publicvoid setIndexes(int[] indexes){ D5T0o"A
this.indexes = indexes; ^sZHy4-yK#
} arPqVMVr
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publicint getStartIndex(){ M>Ws}Y
return startIndex; $>~4RXC
} b#e|#!Je
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publicvoid setStartIndex(int startIndex){ AK;G_L
if(totalCount <= 0) AQBr{^inH|
this.startIndex = 0; [aC2ktI
elseif(startIndex >= totalCount) !ImtnU}
this.startIndex = indexes iV%tn{fc
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[indexes.length - 1]; IW|1)8d
elseif(startIndex < 0) 5|[\Se#
this.startIndex = 0; `WU"*HqW
else{ [k
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this.startIndex = indexes zQ eXN7$
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[startIndex / pageSize]; i*vf(0G
} I'uRXvEr7
} .7zdA IKW
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publicint getNextIndex(){ ~_L_un.R
int nextIndex = getStartIndex() + 78+PG(Q_M
^$O,Gy) V
pageSize; *$7c||J7
if(nextIndex >= totalCount) ?Da!QH
>,]
return getStartIndex(); ,}#l0BY
else yX8$LOjE
return nextIndex; A0Hs d
} Z4Qq#iHZR
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publicint getPreviousIndex(){ ny~~xQ"
int previousIndex = getStartIndex() - M>g\Y
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pageSize; vvG#O[| O
if(previousIndex < 0) pEE.%U
return0; Ey;uaqt
else n P4DHb&5
return previousIndex; pTJJ.#$CEF
} ;HeUD5Nt6F
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} ]T! >]
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抽象业务类 .qCD(XZ+
java代码: /u8m|S<
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/** Q_F8u!qrZ
* Created on 2005-7-12 aD@sb o
*/ =q(;g]e
package com.javaeye.common.business; tQ:)j^\
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import java.io.Serializable; l(@UpV-
import java.util.List; $!x8XpR8s
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import org.hibernate.Criteria; nDSmr
import org.hibernate.HibernateException; --S2lN/:T
import org.hibernate.Session; Bp`?inKBOd
import org.hibernate.criterion.DetachedCriteria; Nj_h+=UE!
import org.hibernate.criterion.Projections; +tNu8M@xFo
import DUxj^,mf,
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org.springframework.orm.hibernate3.HibernateCallback; @""aNKA^r>
import R*D0A@
$4y;F]
org.springframework.orm.hibernate3.support.HibernateDaoS kckWBL
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upport; AAE8j.
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import com.javaeye.common.util.PaginationSupport; t%wC~1
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public abstract class AbstractManager extends $UAmUQg)}_
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HibernateDaoSupport { gf^"sfNk
ika/ GG
privateboolean cacheQueries = false; : uglv6
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@&(
privateString queryCacheRegion; K%ltB&
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publicvoid setCacheQueries(boolean ML!Zm[I9
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cacheQueries){ %Uj7g>
this.cacheQueries = cacheQueries; ;#G)([
} &{?*aK&%3l
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publicvoid setQueryCacheRegion(String !SAjV)
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queryCacheRegion){ <J4|FOz!=
this.queryCacheRegion = 8|uFW7Q
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queryCacheRegion; lL.3$Rp;
} a,3}
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publicvoid save(finalObject entity){ E(F<shT#
getHibernateTemplate().save(entity); |[/[*hDZ9
} :|3n`,
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publicvoid persist(finalObject entity){ \M-}(>Pfk
getHibernateTemplate().save(entity); ^W|B Xxo
} #gzY _)E
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publicvoid update(finalObject entity){ QZ!;` ?(
getHibernateTemplate().update(entity); x#ub % t
} JX%B_eUlAs
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publicvoid delete(finalObject entity){ V3j1M?>
getHibernateTemplate().delete(entity); 5 Z+2
} ;fLYO6
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publicObject load(finalClass entity, $xRZU9+
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finalSerializable id){ ZPHiR4fQli
return getHibernateTemplate().load %$K2$dq5
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(entity, id); g.![>?2$8
} =\;yxl
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publicObject get(finalClass entity, *7: )k
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finalSerializable id){ d~B]s
return getHibernateTemplate().get 6E~T$^Q}
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(entity, id); 6q^Tq {I
} 2
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publicList findAll(finalClass entity){ ,})x1y
return getHibernateTemplate().find("from Q2[@yRY/z
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" + entity.getName()); So &c\Ff
} n{oRmw-
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publicList findByNamedQuery(finalString &w@~@]
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namedQuery){ e_3KNQ`kA
return getHibernateTemplate L@> +iZSO
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().findByNamedQuery(namedQuery); ="fq.Tt
} !FwR7`i
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publicList findByNamedQuery(finalString query, |~Q`DdkX
# 3{g6[Y
finalObject parameter){ n^OWz4
return getHibernateTemplate DoV<p?U
HD"Pz}k4
().findByNamedQuery(query, parameter); -~z]ut<Z
} CS[[TzC=5
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publicList findByNamedQuery(finalString query, V'vDXzk\
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finalObject[] parameters){ q0Rd^c
return getHibernateTemplate OE,uw2uaT
!_{2\&
().findByNamedQuery(query, parameters); 4}nsW}jCc
} utk'joo
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publicList find(finalString query){ _ PC}`Y'&
return getHibernateTemplate().find qta^i819
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(query); =X6+}YQ"
} u@!iByVAg
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publicList find(finalString query, finalObject 4{2)ZI#
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parameter){ 9:tvkl
return getHibernateTemplate().find .:eNL]2%:
_;*|"e@^
(query, parameter); fneg[K
} QInow2/u
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public PaginationSupport findPageByCriteria h'8w<n+%)
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(final DetachedCriteria detachedCriteria){ BV=L.*
return findPageByCriteria :sT\-MpQvn
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); RZykwD(
} t
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public PaginationSupport findPageByCriteria r.e,!B s
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(final DetachedCriteria detachedCriteria, finalint m.~&n!1W*`
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startIndex){
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return findPageByCriteria iR-MuDM
q9n0bw^N
(detachedCriteria, PaginationSupport.PAGESIZE, 51oZw%os=
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startIndex); y%T5"p$,
} {b@rQCre7
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public PaginationSupport findPageByCriteria /Cd`h;#@
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(final DetachedCriteria detachedCriteria, finalint 7#Qa/[? D
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pageSize, g%w@v$
finalint startIndex){ #80*3vi~F
return(PaginationSupport) zT}Q rf~
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getHibernateTemplate().execute(new HibernateCallback(){ qlUYu"`i
publicObject doInHibernate 5 Vm
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(Session session)throws HibernateException { 06bl$%
Criteria criteria = "AjtNL5
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detachedCriteria.getExecutableCriteria(session); `~( P
int totalCount = kmM4KP#&|
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((Integer) criteria.setProjection(Projections.rowCount Fz+0 h"
;K?fAspSH
()).uniqueResult()).intValue(); Fi{~UOZg
criteria.setProjection 0|X!Uw-Q%_
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(null); %l@Q&)f8e
List items = sY,!Ir`/`
@]f"X>
criteria.setFirstResult(startIndex).setMaxResults l79jd%/m
q>&F%;q1]
(pageSize).list(); ?r@euZ&
PaginationSupport ps = ~B%EvG7:n
N}\Da:_
new PaginationSupport(items, totalCount, pageSize, WfVkewuPo
i L1.R+
startIndex); /2oTqEqaV
return ps;
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} 3nBbPP_
}, true); ww"ihUX
} *qg9~/
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public List findAllByCriteria(final wxZnuCO%H8
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DetachedCriteria detachedCriteria){ G#'3bxI{f+
return(List) getHibernateTemplate A"Rzn1/
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().execute(new HibernateCallback(){ =ox#qg.5
publicObject doInHibernate ^ j@Q2>&?
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(Session session)throws HibernateException { 9#%(%s2+
Criteria criteria = uqZLlP#
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detachedCriteria.getExecutableCriteria(session); :5?ti
return criteria.list(); 0c1}?$f[?%
} C5Q|3d
}, true); SPsq][5eR
} l3}n.ODA
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public int getCountByCriteria(final P<kTjG
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DetachedCriteria detachedCriteria){ c}mJ6Pt
Integer count = (Integer) #s1M>M)
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getHibernateTemplate().execute(new HibernateCallback(){ NpD}7t<EF
publicObject doInHibernate GT%V,OJ
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(Session session)throws HibernateException { U=XaI%ZM)
Criteria criteria = #`a-b<uz
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detachedCriteria.getExecutableCriteria(session); CV4V_G
return U^Z[6u
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criteria.setProjection(Projections.rowCount 5HG 7M&_
.mDqZOpf=4
()).uniqueResult(); o;Zoj}
} ,-CDF)~G=3
}, true); vyV n5s
return count.intValue(); RYE::[O7
} $},:z]%D
} TFxb\
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用户在web层构造查询条件detachedCriteria,和可选的 94APjqV6'
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 X3L9j(
(%#d._j>fZ
PaginationSupport的实例ps。 o9wg<LP
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ps.getItems()得到已分页好的结果集 .ET;wK
ps.getIndexes()得到分页索引的数组 JIb<>X,
ps.getTotalCount()得到总结果数 Pms3X
ps.getStartIndex()当前分页索引 xOT'4v&.
ps.getNextIndex()下一页索引 xxkP4,(p
ps.getPreviousIndex()上一页索引 9,`mH0jP
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 |B` -chK
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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 EE}NA{b
}#'KME4
一下代码重构了。 8@hzw~>
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我把原本我的做法也提供出来供大家讨论吧: MCh8Q|Yx4
8~HC0o\2
首先,为了实现分页查询,我封装了一个Page类: b V9Z[[\
java代码: Ysr{1! K
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/*Created on 2005-4-14*/ ePs<jrB<
package org.flyware.util.page; h*MR5qa
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/** e982IP
* @author Joa nrt0[E-&~
* l42m81x"
*/ yFpHRfF}
publicclass Page { w|L~+
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/** imply if the page has previous page */ 5?O/Aub
privateboolean hasPrePage; Q`vyDoF
{t=Nnc15K
/** imply if the page has next page */ keJec`q=X
privateboolean hasNextPage; s`#hk^{
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/** the number of every page */ *0c
}`|
privateint everyPage; :W1,s53
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/** the total page number */ MxdfuFss
privateint totalPage; v,D_^?] @
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/** the number of current page */ ';ZJuJ.
privateint currentPage; WN?T*bz2
8fe"#^"s R
/** the begin index of the records by the current g u|;C
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query */ >}4]51s
privateint beginIndex; ) F~>
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Ql}
/** The default constructor */ <`r+l5
public Page(){ KPR{5
*z+\yfOO"
} D{loX6
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/** construct the page by everyPage }oN(nPxv9
* @param everyPage T^nX+;:|
* */ I2W2B3D` c
public Page(int everyPage){ Vks,3$
this.everyPage = everyPage; v
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} J<BdIKCma
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/** The whole constructor */ )_Oc=/c|f
public Page(boolean hasPrePage, boolean hasNextPage, z5vryhX_Z
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int everyPage, int totalPage, Z~c7r n
int currentPage, int beginIndex){ Bjo&
this.hasPrePage = hasPrePage; 0ay!tS
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this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; (mD]}{>
this.totalPage = totalPage; SW; bE
this.currentPage = currentPage; ]rN fr-
this.beginIndex = beginIndex; +[qkG.
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} L_.}z)S[\
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/** 0*AlLwO
* @return ua[\npz5
* Returns the beginIndex. V8sY7QK=
*/ q@sH@-z4]
publicint getBeginIndex(){ W" !amMQ
return beginIndex; @s@
} 1(?J>{-lw
9Ac t<(V
/** -24.[E/5
* @param beginIndex &q<8tTW5
* The beginIndex to set. IW1\vfe
*/ QVH_B+
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publicvoid setBeginIndex(int beginIndex){ FO5SXwx
this.beginIndex = beginIndex; 5`uS<[vA
} i3"sArP"|
"_K 6=
/** /iN\)y#u1
* @return h|H;ZC(B
* Returns the currentPage. GMNb;D(>K
*/ yTn@p(J
publicint getCurrentPage(){ b910Z?B^L
return currentPage; bpx=&74,6m
} KCT8Q!\
-,;Ep'
/** <^\r9Qxl
* @param currentPage \nHlI=!P
* The currentPage to set. :A'!u r=\
*/ <S}qcjG
publicvoid setCurrentPage(int currentPage){ kW~F*
this.currentPage = currentPage; ry\']\k
} o{he)r6)_
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/** #Kl2K4
* @return +o3g]0
* Returns the everyPage. z3C^L
*/ 8<kme"%s
publicint getEveryPage(){ #~+#72+x7
return everyPage; asi1c
y\
} X]fw9tZ
3XnXQ/({
/** oW[,EW+u
* @param everyPage &rl>{Uvq
* The everyPage to set. $Y`aS^IW
*/ U.aa iX7
publicvoid setEveryPage(int everyPage){ *X\c
$=*
this.everyPage = everyPage; W.|6$hRl)
} LasH[:QQQ
r$F]e]Ic\
/** p.9v<I%0
* @return y]l"u=$Tr{
* Returns the hasNextPage. <J)A_Kx[57
*/ 2mUu3fZ
publicboolean getHasNextPage(){ _}&]`,s>
return hasNextPage; C6VoOT)\
} [&CM-`
N
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/** W/>?1+r.Z
* @param hasNextPage iy]}1((hR
* The hasNextPage to set. $3TTHS o
*/ i .N1Cvp&
publicvoid setHasNextPage(boolean hasNextPage){ 7fay:_
this.hasNextPage = hasNextPage; $vBU}~l7
} >, E$bm2
9+QrTO
/** 5E!m! nBZ
* @return S=}~I
* Returns the hasPrePage. 9oP{Al
*/ *d@Hnu"q
publicboolean getHasPrePage(){ yj~"C$s
return hasPrePage; EaD@clJS
} =%\6}xPEl<
pxxFm~"d
/** qDM[7q3.
* @param hasPrePage +q/h:q.TV
* The hasPrePage to set. Qu,k
*/ jw[BtRW
publicvoid setHasPrePage(boolean hasPrePage){ *Zi%Q[0Me
this.hasPrePage = hasPrePage; p'uz2/g
} $ rYS
&=Zg0Q
/** CFm1c1%Hg
* @return Returns the totalPage. HY4E
* F2$bUY
*/ nb_^3K]r
publicint getTotalPage(){ 2<G1'7)
return totalPage; q|X4[E|{Q
} qffSq](D.
nV3
7`
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/** Tr0V6TS7
* @param totalPage &H&P)Px*_
* The totalPage to set. \83A|+k
*/ ^|GtO.
publicvoid setTotalPage(int totalPage){ n2mw@Ay!
this.totalPage = totalPage; ox_h9=$-
} r.b6E% D
7J;~&x
} Tud1xq
y,?G75wij
J md
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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 2A}u qaF
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个PageUtil,负责对Page对象进行构造: S<3!oDBs
java代码: wDSUMB<?
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;3|Lw<D5;
/*Created on 2005-4-14*/ G'2=jHzMF
package org.flyware.util.page; fG2&/42J
(kQ.tsl
import org.apache.commons.logging.Log; rz}l<t~H
import org.apache.commons.logging.LogFactory; 0BB@E(*
rm=~^eB
/** :{s%=\k {d
* @author Joa Q|B|#?E==
* ; eF4J
*/ Rca
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publicclass PageUtil { $SzCVWS
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privatestaticfinal Log logger = LogFactory.getLog 9G&l qfX:
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(PageUtil.class); C^" Hj
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/** |SP.S 0.y
* Use the origin page to create a new page tnF9Vj[#%_
* @param page mvA xx`jc
* @param totalRecords *:T>~ilF
* @return s`iNbW="
*/ cL)rjty2
publicstatic Page createPage(Page page, int c =N]!
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totalRecords){ @=0r3
return createPage(page.getEveryPage(), boF4d'g"
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page.getCurrentPage(), totalRecords); "h^#<bPN
} dA)4(0o8fD
3.<6;?
/** G#n^@kc*,
* the basic page utils not including exception Sd\IGy{a
i9\\evJs
handler 12d}#G<q-
* @param everyPage :uwRuPI
* @param currentPage ?gR\A8:8
* @param totalRecords nG^M 2)(8
* @return page wEfz2Eq
*/ C*s0r;
publicstatic Page createPage(int everyPage, int rF'^w56
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currentPage, int totalRecords){ P"=UI$HN
everyPage = getEveryPage(everyPage); 8q~FUJhU
currentPage = getCurrentPage(currentPage); '!fFI 1s
int beginIndex = getBeginIndex(everyPage, LA+$_U"Jk
loC5o|Wh
currentPage); ) qyx|D
int totalPage = getTotalPage(everyPage, ~f=6?5.wa
dx13vZ3[U
totalRecords); XW~ BEa
boolean hasNextPage = hasNextPage(currentPage, tT* W5
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totalPage); n.a=K2H:V
boolean hasPrePage = hasPrePage(currentPage); nrS[7~
LN.Bd,
returnnew Page(hasPrePage, hasNextPage, *K}z@a_
everyPage, totalPage, :nKsZ1b X
currentPage, d7gH3 l
V8nz-DL{
beginIndex); g^z5fFLg/8
} Tw}?(\ya
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privatestaticint getEveryPage(int everyPage){ 2%5^Fi
return everyPage == 0 ? 10 : everyPage; ?79SP p)oo
} urT/+deR
oBRm\8 2|
privatestaticint getCurrentPage(int currentPage){ 8tV=fSHd
return currentPage == 0 ? 1 : currentPage; EFRZ% Y
} B;z>Dd,Y_x
W>?f^C!+m
privatestaticint getBeginIndex(int everyPage, int K#l
-?
aT?p>
currentPage){ y /X:=d6"
return(currentPage - 1) * everyPage; -t%{"y
} Iuu<2#gb8"
4T==A#Z
privatestaticint getTotalPage(int everyPage, int uG=t?C6
^J#?hHz
totalRecords){ ;/?Z<[B
int totalPage = 0; >}<29Ii
|t&G&)~:
if(totalRecords % everyPage == 0) *`+<x
totalPage = totalRecords / everyPage; ;!l*7}5X=
else #gX%X~w$F
totalPage = totalRecords / everyPage + 1 ; 3R<ME c
IW1GhZ41'
return totalPage; 1A%N0#_(Md
} tDC0-N&6S~
;#Jq$v)D
privatestaticboolean hasPrePage(int currentPage){ J.bFv/R
return currentPage == 1 ? false : true; 0<]$v"`I
} 7m|`tjQ1
F@=e2e
4
privatestaticboolean hasNextPage(int currentPage, zj~nnfoys
io9y;S"+
int totalPage){ VM-qVd-
return currentPage == totalPage || totalPage == _=|nOj39
_l24Ba$F6
0 ? false : true; }g>dn
} HF&h
7oZ@<QP'
nd $H
3sf
} |~@x4J5,
--in+
C2+{U
?(5o@Xq
U8-Q'1IT&
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 j>$=SMc
pau*kMu^}
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 tJUVw=
{E3xI2
做法如下: Ne &Xf
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 o,?!"*EP
=7 Jy
的信息,和一个结果集List: pT("2:)x
java代码: V*6l6-y~Ih
l;XU#6{
.abyYVrN4?
/*Created on 2005-6-13*/ snXB`UC
package com.adt.bo; RDUT3H6~
4t&gW
import java.util.List; ad"'O]
[3t0M5x w
import org.flyware.util.page.Page; J"%8:pL
+mJ
:PAy4
/** ~gu=x&{
* @author Joa If~95fy~c
*/ 6N9 c<JC
publicclass Result { M:R8<.{
S:/{
private Page page; Qo'yS"g<9)
Oq*n9V
private List content; Iq)(UfaSve
9 wAA.
-"
/** mbF(tSy
* The default constructor rei
8LW
*/ dX_!0E[c
public Result(){ Wt>J`
super(); x|.v{tQa
} mfZ)^X
]kRI}Om2
/** j*tk(o}qG
* The constructor using fields Dq?E\
* fZ[kh{|
* @param page y&1%1 #8F
* @param content i][f#e4
*/ F4GP7]
public Result(Page page, List content){ Dt
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this.page = page; `&7mHa61
this.content = content; #"::
'?,
} fi=0{
DeH0k[o
/** ^uia`sOP4
* @return Returns the content. a* D,*C5}
*/ v9u<F6
publicList getContent(){ ERF,tLa!
return content; w'A tf
} ar Q)%W
%Nj #0YF]
/** QS^~77q
* @return Returns the page. BU!#z(vU
*/ 2R~6<W+&:>
public Page getPage(){ ndr)3tuYu
return page; s8^~NX(xdy
} 88
{1mA,v
fO6[!M(
/** Nu@5 kwH
* @param content G%S6$@:
* The content to set. /?Vdqci
*/ _l<mu? "
public void setContent(List content){ cg,Ua!c
this.content = content; @@Q6TB
} (z/jMMms
j?xk&
/** D z@1rc<B
* @param page \SOeTn+
* The page to set. S`=n&'
*/ @M=$qO_$9
publicvoid setPage(Page page){ !x7o|l|cP
this.page = page; 8"x9#kyU<3
} (_K_`5d;QI
} 6a*83G,k
RwW$O@0
:s"2Da3B
wZjlHe
fp{G|.SA
2. 编写业务逻辑接口,并实现它(UserManager, 8.yCA
c_#*mA"+
UserManagerImpl) Rv<L#!;
t
java代码: ^2EhlK^)
}%$OU = T
?KB@Zm+#~
/*Created on 2005-7-15*/ Ad/($v5+
package com.adt.service; xI?0N<'.*q
'd/*BjNp)
import net.sf.hibernate.HibernateException; mZ7B<F[qV
n3$gx,KL
import org.flyware.util.page.Page; paWxanSt
!MoOKW
import com.adt.bo.Result;
Yl~$V(
"]#'QuR
/** ul@3
Bt
* @author Joa I^G^J M!
*/ h=6xZuA\
publicinterface UserManager { F+ukAT
Q_]~0PoH
public Result listUser(Page page)throws Ux}W&K/?'
|gv{z"
HibernateException; Efx=T$%^&
90fs:.
} >F[GVmC
KQ{Lt?S
<
bFy(+
2n)gpLIJ
d)tiO2W
java代码: HTk\723Rdw
>3PMnI
^"x<)@X
/*Created on 2005-7-15*/ $7NCb7%/L
package com.adt.service.impl; *~2cG;B"e
Pu;yEh
import java.util.List; L^FcS\r;
Ie@Jb{x
import net.sf.hibernate.HibernateException; !n<o)DsZR
E(4w5=8TI
import org.flyware.util.page.Page; ]-:6T0JuS
import org.flyware.util.page.PageUtil; s8vKKvs`9
_Yq@ FOu
import com.adt.bo.Result; u,o1{%O
import com.adt.dao.UserDAO; _ie.| 4k
import com.adt.exception.ObjectNotFoundException; *5D3vB*S
import com.adt.service.UserManager; -Sz_mr
n@
[
/** !D:Jbt@R<n
* @author Joa S!hXf|*0[
*/ 0%<+J;'o
publicclass UserManagerImpl implements UserManager { c)~h<=)
{eQWO.C{
private UserDAO userDAO; GeV+/^u
.z-UOyer
/** UpfZi9v?W
* @param userDAO The userDAO to set. g_aCHEFBv
*/ x[X`a
publicvoid setUserDAO(UserDAO userDAO){ vHcqEV|P/n
this.userDAO = userDAO; `PlOwj@u0`
} {^m Kvc
S6sq#kcH
/* (non-Javadoc) G1d(,4Xp
* @see com.adt.service.UserManager#listUser bL1m'^r
VagT_D
(org.flyware.util.page.Page) 66\jV6eH7L
*/ +Gh7^v|"
public Result listUser(Page page)throws Qxa{UQh}9
D4Etl5k
HibernateException, ObjectNotFoundException { (=c1
int totalRecords = userDAO.getUserCount(); h@1!T
if(totalRecords == 0) <)U4Xz ?
throw new ObjectNotFoundException 5 1dSFr<#
`1+F,&e
("userNotExist"); _<*Hv*Zm
page = PageUtil.createPage(page, totalRecords); )`+YCCa6F
List users = userDAO.getUserByPage(page); pe.QiMW{8
returnnew Result(page, users); `A)"%~
} h<x4YB5Mj
41Ve}%
} 2@khSWV
4kl Ao$
X`JVR"=4
?*u*de[,
Kq)MTlP0g
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 :a0zT#u
_O]xey^r
询,接下来编写UserDAO的代码: (sTuG}
3. UserDAO 和 UserDAOImpl: u:dx;*
java代码: x#H
3=YD*
;\{`Ci\
M.[rLJZ4
/*Created on 2005-7-15*/ "%6/a7S
package com.adt.dao; W?Ww2Lo%Y
=L]Q2V}
import java.util.List; 1/Zh^foG
{38bv.3'
import org.flyware.util.page.Page; -{jdn%Y7CK
v)X\GmW7w
import net.sf.hibernate.HibernateException; SA"8!soY3
J'T=q/
/** rcN 9.1
* @author Joa (u1m]WYL
*/ ~nY]o"8D
publicinterface UserDAO extends BaseDAO { $8~e}8dt|
v]VWDT
`
publicList getUserByName(String name)throws 1iBP,:>*
jZ*WN|FK?
HibernateException; Y.6SOu5$]
u bW]-U=T
publicint getUserCount()throws HibernateException; xTz%nx
W!L+(!&H
publicList getUserByPage(Page page)throws s1j{x&OSq
g(E"4M@t!
HibernateException; t^tmz PWA
gm"#:< )
} }6u2*(TmD
8|^CK|m6*
{*m ?Kc7k
SPkn3D6
5*-3?
<)e
java代码: 7^6uG6
K9Hqq7"%
/j2H A^GT
/*Created on 2005-7-15*/ #q\x$
package com.adt.dao.impl; vX|UgK?2^
*m+BuGt|
import java.util.List; 9&]M**X
\wvg,j=
import org.flyware.util.page.Page; 0Q5^C!K
!ZXUPH
import net.sf.hibernate.HibernateException; pv)`%<
import net.sf.hibernate.Query; #I*QX%(H#
~ 5"JzT
import com.adt.dao.UserDAO; @OpNHQat9
/0MDISQy9
/** *#
{z 3{+
* @author Joa ;q>9W,jy
*/ zCaT tb|@
public class UserDAOImpl extends BaseDAOHibernateImpl XzIx:J6
w?Ju5 5
implements UserDAO { R9+jW'[K
5VW|fI
/* (non-Javadoc) q8P.,%
* @see com.adt.dao.UserDAO#getUserByName 7V7zGx+Z7
rVnd0K
(java.lang.String) "2ru 7Y"
*/ _HOIT
publicList getUserByName(String name)throws r=.A'"Kf
J Yb}Zw;
HibernateException { 2/
rt@{V(
String querySentence = "FROM user in class ~wm;;#_O
(5L-G{4
com.adt.po.User WHERE user.name=:name"; kS5_
Query query = getSession().createQuery :iWS\G^U
fh8j2S9J
(querySentence); /# NYi,<{X
query.setParameter("name", name); Q
n)d2-<
return query.list(); $tqJ/:I
} T#@lDpO
1Tp/MV/>
/* (non-Javadoc) $g9**b@
* @see com.adt.dao.UserDAO#getUserCount() oPf)be| #
*/ >R,'5:Rw
publicint getUserCount()throws HibernateException { U&Wwyu:4i
int count = 0; pmvT$;7I
String querySentence = "SELECT count(*) FROM &
WOiik
Elj_,z
user in class com.adt.po.User"; {y= W6uP
Query query = getSession().createQuery >4` dy
SMr13%KN/
(querySentence); n{0Ld -zH
count = ((Integer)query.iterate().next qFX~[h8i+
U @v*0
()).intValue(); oTjyN\?H
return count; 2NGeC0=
} p/Sbt/R
VZka}7a
/* (non-Javadoc) eDI=nSo
* @see com.adt.dao.UserDAO#getUserByPage m><w0k?t
N7r_77%m0
(org.flyware.util.page.Page) `$LWmm#
*/ 6DIZ@ oi
publicList getUserByPage(Page page)throws u|#>32kV
4LcX<BU9
HibernateException { RprKm'b8x`
String querySentence = "FROM user in class 2zSG&",2D
o Pci66
com.adt.po.User"; QS.>0i/7l
Query query = getSession().createQuery R:-JkV>e:
asiov[o;
(querySentence); 6d[_G$'nk
query.setFirstResult(page.getBeginIndex()) gU^$Sx7'
.setMaxResults(page.getEveryPage()); -Y#sI3o*R8
return query.list(); 8M,9kXq{L
} OI1ud/>h
#eZ6)i<
} >Hb^P)3
KOq;jH{$
lASL8O&\
n]_[NR) i
UV
4>N
至此,一个完整的分页程序完成。前台的只需要调用 RgdysyB
YpAg
userManager.listUser(page)即可得到一个Page对象和结果集对象 |'ln?D:&
n6d9\
的综合体,而传入的参数page对象则可以由前台传入,如果用 V"o7jsFH6n
Jf)bHjC_V
webwork,甚至可以直接在配置文件中指定。
JCcZuwu[
9fnA
下面给出一个webwork调用示例: YYEJph@06q
java代码: %=AxJp!a
zJDSbsc$%
N /$`:8"
/*Created on 2005-6-17*/ _-!sBK+F
package com.adt.action.user; eivtH P
Ma *y=d;,1
import java.util.List; z{"2S="
lU^;Z6f
import org.apache.commons.logging.Log; {CG_P,FO
import org.apache.commons.logging.LogFactory; 3nZ9m
import org.flyware.util.page.Page; jCAC
`
4(neKr5\#
import com.adt.bo.Result; TC~Q
G$NW
import com.adt.service.UserService; FsB^CxVg
import com.opensymphony.xwork.Action; (6CN/A{qe
M2x["
/** #*$P'r
* @author Joa 5ercD
*/ !MDNE*_
publicclass ListUser implementsAction{ )D'^3)FF
u<q :$
privatestaticfinal Log logger = LogFactory.getLog H.<a`mm8
e~ aqaY~}
(ListUser.class); [3l*F
93+"D`
private UserService userService; _zt19%Wg
8(.mt/MR
private Page page; R+q"_90_
[%50/_h
privateList users; kg][qn|>J]
jV#ahNq;
/* n?\ nn3
* (non-Javadoc) &
gJV{V5Ay
* ""Zp:8o
* @see com.opensymphony.xwork.Action#execute() ^JZ^>E~
*/ \\BCcr\l
publicString execute()throwsException{ >-_d CNZ
Result result = userService.listUser(page); id<:p*
page = result.getPage(); G$'jEa<:u
users = result.getContent(); v5;I]?72l~
return SUCCESS; 9Suu-A
} wiaX&-c]8
IM$2VlC
/** w{~+EolK
* @return Returns the page. ms($9 Lv/
*/ PiV7*F4qI.
public Page getPage(){ n9pN6,o+
return page; 1Gt/Tq$_b
} <PPNhf8
:+{ ?
/** ZT02"3F
* @return Returns the users. "G-1>:
*/ fP3_d
publicList getUsers(){ 4`Q3v4fOF
return users; JOjoiA
} 5Zmw} M
oLWJm
/** Wv__ wZ
* @param page Tu{h<Zy
* The page to set. )!g{Sbl
*/ EFpIp4_Y
publicvoid setPage(Page page){ hS[yNwD
this.page = page; t1VH doNN
} 2^t#6XBk/
+(xeT+J
/** vA$o~?a]/
* @param users bifS 2>c
* The users to set. ]M)O YY
*/ 1)}=bhT
publicvoid setUsers(List users){ ^8 ' sib
this.users = users; J--m[X
} T081G`li
\MxoZ
/** QKN<+,h!z>
* @param userService DC1'Kyk
* The userService to set. =0@&GOq
*/ 9Rek4<5
publicvoid setUserService(UserService userService){ iX'rU@C
this.userService = userService; Lokl2o`
} t+,4Ya|Xj
} Ladsw
Xtwun
AamVms
oG$)UTzGc
LlBN-9p
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, liR?
:K\mN/ x
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 O62b+%~F
pV6d
Id
么只需要: K1V#cB
WO
java代码: {;2vmx9
&a/__c/l
USN8N (
<?xml version="1.0"?> "NRDNqj(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork !6Sd(2
!*2%"H*
1.0//EN" "http://www.opensymphony.com/xwork/xwork- dd?x(,"A`
0y&I/2
1.0.dtd"> 8/z3=O&
SuZ&vqS
<xwork> Z):n c% S
R3k1RE2c&g
<package name="user" extends="webwork- kNu'AT#3|
`h}q
Eo`
interceptors"> 9N%JP+<89
H
_Va"yTO6
<!-- The default interceptor stack name nhG
J
"O8gJ0e
--> IVlf=k
<default-interceptor-ref
E7Cy(LO
+UJuB
name="myDefaultWebStack"/> _C\[DR0n
=)O,`.M.Y
<action name="listUser" ogFKUD*h&>
x{NX8lN
class="com.adt.action.user.ListUser"> z} '! eCl
<param *m%]zj0bo
$+}+zZX5
name="page.everyPage">10</param> h7s;m
<result [ofqGwpDG
nW"q
name="success">/user/user_list.jsp</result> y*{Zbz#{
</action> %gnM(pxl
gX{loG
</package> TpA\9N#$
T0)"1D<l
</xwork> _LwOOZj
vIvVq:6_3
EQqx+J&!
kY]W
Qu
PpLU
[sW.CK=3
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 Og;-B0,A
^\B:R,
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。 G8W#<1LE
RtG}h[k/X
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 iR$<$P5
VL[)[~^
KRJLxNr
)} DUMq7
*&AfR8x_z
我写的一个用于分页的类,用了泛型了,hoho s] /tYJYl
P,ua<B}L
java代码: A?TBtAe
/ug8]Lo0
xf%4, JQ
package com.intokr.util; \,!QJp4
F_xbwa*=
import java.util.List; 8 i&_Jgmr
;X ,1I
/** R{,ooxH\J
* 用于分页的类<br> 3Rm#-T s
* 可以用于传递查询的结果也可以用于传送查询的参数<br> A?G IBjs
* m~Ld~I"
* @version 0.01 yBLK$@9
* @author cheng 6)pH|d.FR
*/ 4[ryKPa,
public class Paginator<E> { ,mPnQ?
privateint count = 0; // 总记录数 avmcw~
TF
privateint p = 1; // 页编号 Y+/JsOD
privateint num = 20; // 每页的记录数 [nxE)D
privateList<E> results = null; // 结果 SPj><5Ro
{;2i.m1
/** $-+/$!
* 结果总数 ~-a'v!
*/ O7']
publicint getCount(){ @{h?+
d
return count; PLM _#+R>
} 1
4LI5T
*zO&N^X.4
publicvoid setCount(int count){ cYNJhGY
this.count = count; L]a`"CH:a$
} TEUY3z[g
KlK`;cr?
/** U=bEA1*@0
* 本结果所在的页码,从1开始 eUS
* 'H9=J*9oG
* @return Returns the pageNo. Bs`$ i ;&
*/ c41: !u^
publicint getP(){ uhN%Aj\iu(
return p; NGYyn`Lx
} h5
Vv:C
+b;hBb]R
/** wx=0'T-[
* if(p<=0) p=1 =1dI>M>tm
* ^s\3/z>b4!
* @param p qdCWy
*/ T~sTBGcv
publicvoid setP(int p){ ]j>i.5
if(p <= 0) OEdJc\n_R
p = 1; ujW1+Oj=~
this.p = p; h72UwJ2rw
} 4VN aq<8
l? #xAZx&_
/** a)*6gf<