Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 %`k [xz
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 P9
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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 Mrgj*|
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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 4o M~
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分页支持类: ynM:]*~K
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java代码: G7CkP
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package com.javaeye.common.util; RiAg:
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import java.util.List; 'gor*-o:wu
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publicclass PaginationSupport { :(ql=+vDb4
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publicfinalstaticint PAGESIZE = 30; [- 92]
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privateint pageSize = PAGESIZE; vdn)+fZ;
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privateList items;
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privateint totalCount; ?bM%#x{e
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privateint[] indexes = newint[0]; X@[5nyILf
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privateint startIndex = 0; sE&nEc
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public PaginationSupport(List items, int j?*n@'
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totalCount){ 2~/`L=L
setPageSize(PAGESIZE); ):hz/vZ
setTotalCount(totalCount); ,=C ipL9]
setItems(items); PTe$dPB
setStartIndex(0); G"&$7!6[Y
} MVzj7~+
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public PaginationSupport(List items, int l
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totalCount, int startIndex){ JdI*@b2k[
setPageSize(PAGESIZE); V^FM-bg%9
setTotalCount(totalCount); cHr]{@7Cs
setItems(items); )MI w/
setStartIndex(startIndex); s1]Pv/a=y
} 5K9W5hA:D
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public PaginationSupport(List items, int >.P*lT
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totalCount, int pageSize, int startIndex){ 4J,6cOuW4
setPageSize(pageSize); w7~]c,$y.
setTotalCount(totalCount); h{-en50tN
setItems(items); Ke@Bf
setStartIndex(startIndex); &/uakkS
} +1qvT_
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publicList getItems(){ dk]
return items; p=[dt
} o(v`
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publicvoid setItems(List items){ nUONI+6Z/
this.items = items; |U1u:=[
} ;w%g*S
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publicint getPageSize(){ o>]w76A^(
return pageSize; J.2BBy
} 0j;|IU\
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publicvoid setPageSize(int pageSize){ >Gg[J=7`
this.pageSize = pageSize; i-0AcN./p
} "OUY^ cM
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publicint getTotalCount(){ 6"?#s/fk
return totalCount; 7 je1vNs
} ZKI` ;
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publicvoid setTotalCount(int totalCount){ *sfz+8Y
if(totalCount > 0){ K24y;968
this.totalCount = totalCount; /%?bO-
int count = totalCount / g+.E=Ef8<4
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pageSize; >>J!|
if(totalCount % pageSize > 0) &#q%#M:
count++; Z#%77!3
indexes = newint[count]; g5Hsz,x
for(int i = 0; i < count; i++){ z9#jXC#OdN
indexes = pageSize * 2(D&jL
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} -IV-"-6(
}else{ H~hAm
this.totalCount = 0; \BsvUGd
} DUm/0q&
} MT&q~jx*
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publicint[] getIndexes(){ ER$~kFE2yP
return indexes;
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} zgpPu4t
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publicvoid setIndexes(int[] indexes){ JY>I
this.indexes = indexes;
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} i%B$p0U<
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publicint getStartIndex(){ !C0=
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return startIndex; `V0]t_*D
} F{<rIR
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publicvoid setStartIndex(int startIndex){ 8%U)EU
if(totalCount <= 0) qdu:kA:]
this.startIndex = 0; }`^<ZNkb/
elseif(startIndex >= totalCount) IPE(
this.startIndex = indexes B "}GAk}V
%s)E}cGH
[indexes.length - 1]; ;6)|'3.B9
elseif(startIndex < 0) WCWBvw4&"{
this.startIndex = 0; 2W~2Hk=0+%
else{ /ci.IT$Q^
this.startIndex = indexes +Q_Gm3^
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[startIndex / pageSize]; QU4'x4YS
} Ip1QmP
} n:!J3pR
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publicint getNextIndex(){ >\p}UPx
int nextIndex = getStartIndex() + \1B*iW
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pageSize; <*5D0q#~"
if(nextIndex >= totalCount) u})JQ<|
return getStartIndex(); ?x/L"h&Kp
else },L[bDOV07
return nextIndex; jKQP0 t-
} aY+>85?g
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publicint getPreviousIndex(){ _1JvA-
int previousIndex = getStartIndex() - q.X-2jjpx:
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pageSize; 5astv:p,P
if(previousIndex < 0) K^vMIo h
return0; #sHP\|rA
else :R&tO3_F
return previousIndex; \
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} >) ^!gz8
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} cS[`1y,\3
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抽象业务类 +$'/!vN
java代码: :4Vt
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/** KKzvoc?Bt
* Created on 2005-7-12 1$W!<:uh
*/ ?m.4f&X
package com.javaeye.common.business; v]!7=>/2
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import java.io.Serializable; Ui.F<,E
import java.util.List; m}E$6E^~O
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import org.hibernate.Criteria; g/J!U8W"
import org.hibernate.HibernateException; 2S4z$(x3
import org.hibernate.Session; }ie]7N6;
import org.hibernate.criterion.DetachedCriteria; tQ67XAb
import org.hibernate.criterion.Projections; v>5F[0gE
import uI[*uAR
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org.springframework.orm.hibernate3.HibernateCallback; 4Ojw&ys@V
import (r4\dp&
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org.springframework.orm.hibernate3.support.HibernateDaoS [C6?:'}FA
6>I.*Qt \l
upport; URgF8?n
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import com.javaeye.common.util.PaginationSupport; ~e<<aTwN
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public abstract class AbstractManager extends z"#.o^5
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HibernateDaoSupport { xTMTkVa+B
%-Z~f~<?
privateboolean cacheQueries = false; ?r<F\rBT7*
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privateString queryCacheRegion; Kc0OLcu^d
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publicvoid setCacheQueries(boolean o{p_s0IX;S
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cacheQueries){ }[`?#`sW
this.cacheQueries = cacheQueries; {)qP34rM
} aw1J#5j`n
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publicvoid setQueryCacheRegion(String Uj)]nJX
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queryCacheRegion){ 1\0@?6`^
this.queryCacheRegion = ZZ*k3Ce
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queryCacheRegion; >ULp!
} m9@n
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publicvoid save(finalObject entity){ ,IE0+!I
getHibernateTemplate().save(entity); Ui!|!V-
} @/L. BfTz
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publicvoid persist(finalObject entity){ Vz]=J;`Mz
getHibernateTemplate().save(entity); I >Q,]S1h
} z_@zMLs
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publicvoid update(finalObject entity){ Els= :4
getHibernateTemplate().update(entity); {C6;$#7P
} ot#kU 8f
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publicvoid delete(finalObject entity){ ,
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getHibernateTemplate().delete(entity); 1o 78e2B
} ]_8I_VcQ
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publicObject load(finalClass entity, %W;Gf9.w
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finalSerializable id){ Tk&9Klo
return getHibernateTemplate().load z|)1l`
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(entity, id); l>Ja[`X@
} .oN
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publicObject get(finalClass entity, 6D"`FPC
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finalSerializable id){ y7EX&
return getHibernateTemplate().get _J~ta.
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(entity, id); @i-@mxk6<
} F6]!?@
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publicList findAll(finalClass entity){ {}&f\6OI%
return getHibernateTemplate().find("from h=r<
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" + entity.getName()); [k7N+W8
} qZ_fQ@
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publicList findByNamedQuery(finalString Y_>-p(IH
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namedQuery){ 4$DliP
return getHibernateTemplate m3Z}eC8LK
cW\Y?x
().findByNamedQuery(namedQuery); C"Q=(3
} G|oB'~{&
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publicList findByNamedQuery(finalString query, Z6([/n
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finalObject parameter){ _6S
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return getHibernateTemplate gXLZ) >+A+
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().findByNamedQuery(query, parameter); 3et2\wOX1x
} m-S33PG{
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publicList findByNamedQuery(finalString query, `NWgETf^#
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finalObject[] parameters){ ji)4WG/1
return getHibernateTemplate vWi.[]
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().findByNamedQuery(query, parameters); LVFsd6:h
} qwNKRqT
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publicList find(finalString query){ {F6dSF`
return getHibernateTemplate().find nL(%&z \4
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(query); s3_e7D ^H
} 1s}NQ3
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publicList find(finalString query, finalObject kGuk
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parameter){ :OQ:@Yk
return getHibernateTemplate().find 1S[5#ewB;j
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(query, parameter); 'f?&EsIV?
} FH`'1iVH
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public PaginationSupport findPageByCriteria ss0'GfP
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(final DetachedCriteria detachedCriteria){ A{8K#@!
return findPageByCriteria >xZhK63C/
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); *e-ptgO
} R<lNk<
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public PaginationSupport findPageByCriteria 3b?OW7H
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(final DetachedCriteria detachedCriteria, finalint aO^:dl5
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startIndex){ RFn0P)9&
return findPageByCriteria )p!*c,
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(detachedCriteria, PaginationSupport.PAGESIZE, ANFg]g.Az
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startIndex); EOBs}M;
} ,h@R' f!
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public PaginationSupport findPageByCriteria r{q}f)
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(final DetachedCriteria detachedCriteria, finalint 2-$bh
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pageSize, 4j=<p@
finalint startIndex){ *1Ut}
return(PaginationSupport) 4#@W;'
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getHibernateTemplate().execute(new HibernateCallback(){ tIyuzc~U
publicObject doInHibernate 0~Iu7mPY
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(Session session)throws HibernateException { J+}+"h~.
Criteria criteria = 7>'uj7r]=
BLL]^qN;Y
detachedCriteria.getExecutableCriteria(session); u(1J=h
int totalCount = A[^qq UL'
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((Integer) criteria.setProjection(Projections.rowCount aE7u5PM
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()).uniqueResult()).intValue(); " K 8&{=
criteria.setProjection KMK&[E#r
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(null); 861i3OXVE>
List items = p{ @CoOn
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criteria.setFirstResult(startIndex).setMaxResults F-BJe]
0T9@,scY
(pageSize).list(); -,~;qSs
PaginationSupport ps = .
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new PaginationSupport(items, totalCount, pageSize, vix&E`0yD
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startIndex); gohAp
return ps; w`c0a&7
} ] vC=.&]
}, true); le7
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} {8^Gs^c
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public List findAllByCriteria(final .UM<a
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DetachedCriteria detachedCriteria){ nE/=:{~Ws
return(List) getHibernateTemplate D4< -8
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().execute(new HibernateCallback(){ \*f;!{P{
publicObject doInHibernate 6m4Te|
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(Session session)throws HibernateException { _9D|u<D
Criteria criteria = :{[<g](
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detachedCriteria.getExecutableCriteria(session); [f<"p[
return criteria.list(); 2HcsQ*H]G
} j((hqJr
}, true); '5'3_vM
} x!'7yx
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public int getCountByCriteria(final `5~7IPl3
@Z?7E8(
DetachedCriteria detachedCriteria){ 7t'(`A6t/
Integer count = (Integer) :/+>e
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getHibernateTemplate().execute(new HibernateCallback(){ t,RyeS/
publicObject doInHibernate $Axng
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(Session session)throws HibernateException { iJ}2"i7M
Criteria criteria = ,{?wKXJ}L!
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detachedCriteria.getExecutableCriteria(session); *5e<\{!
return cv3L&zg M
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criteria.setProjection(Projections.rowCount P3G:th@j=
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()).uniqueResult(); : (cb2j(C
} C1 W>/?XC
}, true); QV0M/k<'
return count.intValue(); ~L~]QN\3
} XJUEwX
} D -6
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用户在web层构造查询条件detachedCriteria,和可选的 J;~E<_"Hn
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _
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PaginationSupport的实例ps。 Lx%:t YZ
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ps.getItems()得到已分页好的结果集 glx2I_y
ps.getIndexes()得到分页索引的数组 RK-x?ZYH'
ps.getTotalCount()得到总结果数 gwiR/(1
ps.getStartIndex()当前分页索引 &3I$8v|!?
ps.getNextIndex()下一页索引 QWw"K$l
ps.getPreviousIndex()上一页索引 -,^WaB7u\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Pu..NPl+
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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 _dr*`yXi
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一下代码重构了。 B9*Sfw%
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我把原本我的做法也提供出来供大家讨论吧: N<liS3>
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首先,为了实现分页查询,我封装了一个Page类: y@3kU*-1
java代码: 9 #Y2`pT
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/*Created on 2005-4-14*/ `VZZ^K9zR
package org.flyware.util.page; ufPCx|x~
.E$q&7@/j
/** ]G*$W+G]
* @author Joa )~}PgbZ^
* JT)k
*/ #ZlM?Q
publicclass Page { )b92yP{
t8vc@of$c,
/** imply if the page has previous page */ Lm|al.Z
privateboolean hasPrePage; <tuS,.
[))JX"a
/** imply if the page has next page */ &z>q#'X;.
privateboolean hasNextPage; TsD;Kl1
F\LsI;G
/** the number of every page */ QKccrAo
privateint everyPage; -k{Jp/-D
q-
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/** the total page number */ zMGzReJ
privateint totalPage; XG&K32_fs
TQJF+;%
/** the number of current page */ JZ=5Bpw
privateint currentPage; 1lcnRHO
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/** the begin index of the records by the current j Nc<~{/
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query */ cPuHLwwYf
privateint beginIndex; CH;;V3
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/** The default constructor */ ~`R1sSr"
public Page(){ cZi[(K
Q2c*.Y
} Rla4L`X;
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/** construct the page by everyPage 2B` 8eb
* @param everyPage C[YnrI!
* */ }bMWTT
public Page(int everyPage){ C`4gsqD;Z
this.everyPage = everyPage; 2EfflZL3
} :woa&(wN;1
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/** The whole constructor */ 8=Q VN_
public Page(boolean hasPrePage, boolean hasNextPage, O
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int everyPage, int totalPage, N E=
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int currentPage, int beginIndex){ q#vlBL
this.hasPrePage = hasPrePage; 8i:[:Z
this.hasNextPage = hasNextPage; o:UXPAj
this.everyPage = everyPage; !kXeO6X@m
this.totalPage = totalPage; X/+OF'po
this.currentPage = currentPage; If'2rE7J
this.beginIndex = beginIndex; y $V[_TN
} (p |DcA]BX
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/**
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* @return ez*jjm
* Returns the beginIndex. E*|tOj9`1n
*/ (~()RkT
publicint getBeginIndex(){ 9$O@`P\
return beginIndex; ~m`!;rE
} inF6M8
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/** 0H:dv:#WAI
* @param beginIndex [rdsv
* The beginIndex to set. CBHc A'L
*/ ~FUa:KYD
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; @vs@>CYdz
} TnE+[.Qu
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/** bPd-D-R
* @return 509Q0 [k
* Returns the currentPage. z\.1>/Z=
*/ r4eUZ .8R
publicint getCurrentPage(){ V(mnyI
return currentPage; LSkk;)'2K
} OVs wt
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/** )U(u>SV(\
* @param currentPage `ROEV~
* The currentPage to set. p|VcMxT9-
*/ .3wY\W8Dr-
publicvoid setCurrentPage(int currentPage){ ?R6`qe_F
this.currentPage = currentPage; 3jPB#%F
} nGa1a
Y}.Ystem
/** xncwYOz
* @return p4mY0Y]mP
* Returns the everyPage. wO!u!I
*/ +1@AGJU3
publicint getEveryPage(){ ~_ P YNY`"
return everyPage; jA`a/vWu
} iBvOJs
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/** /V^sJ($V$~
* @param everyPage 0HbJKix!
* The everyPage to set. m6U8)!)T
*/ -JTG?JOd]
publicvoid setEveryPage(int everyPage){ $G[KT):N
this.everyPage = everyPage; %f!iHo+Z
} K`4GU[ul
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/** 1xTTJyoq
* @return l)8sw=
* Returns the hasNextPage. 2k+16/T
*/ ~B_ D@gV|
publicboolean getHasNextPage(){ V/bH^@,sA
return hasNextPage; #&siHHs \
} ZvH{wt
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/** yXF|Sqv
* @param hasNextPage Z[}
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* The hasNextPage to set. V^En8
*/ "{(
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publicvoid setHasNextPage(boolean hasNextPage){ K0<yvew
this.hasNextPage = hasNextPage; &=zU611,
} hTw}X.<4
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/** Gvn : c/m;
* @return v@_in(dk
* Returns the hasPrePage. }ywi"k4>
*/ O71BM@2<
publicboolean getHasPrePage(){ E@pFTvo
return hasPrePage; Dh`=ydI5
} 2U%qCfh6|
A&l7d0Z^j5
/** EUZq$@uWL
* @param hasPrePage 8c).8RL f
* The hasPrePage to set. :t>Q:mX(N
*/ +/q0Y`v
publicvoid setHasPrePage(boolean hasPrePage){ \)R-A
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this.hasPrePage = hasPrePage; .Cr1,Po
} *?N<S$m
(1 yGg==W.
/** ;+%Z@b%
* @return Returns the totalPage. J wFned#T
* ][t6VA
*/ b~as64
publicint getTotalPage(){ kY!C_kFcn
return totalPage; s3< F
} `,Zb2"
1;`Fe":;vC
/** JUU&Z[6J
* @param totalPage ^0Q'./A{&
* The totalPage to set. M.[wKGX(
*/ Ilef+V^qr
publicvoid setTotalPage(int totalPage){ bK7.St
this.totalPage = totalPage; _BwKY#09Zp
} qUg9$oh{LI
o=mo/N4
} h0XH`v
M[z3 f
_H2tZ%RM
Y Z\@)D;
>[P%Ty);
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 M8_ R
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个PageUtil,负责对Page对象进行构造: Nm"<!a<F
java代码: \!4|tBKVY
cIZ[[(Db
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/*Created on 2005-4-14*/ :iEA UM
package org.flyware.util.page; .FJj
raF]
k0{
import org.apache.commons.logging.Log; TZBVU&,{Z
import org.apache.commons.logging.LogFactory; 7vq
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/** %yKKUZ~
* @author Joa z \^
* j%u8=
*/ `fMpV8vv
publicclass PageUtil { 3 69Zu4|u
_[%n ~6
privatestaticfinal Log logger = LogFactory.getLog {s9<ej~<R
aPt{C3<
(PageUtil.class); R Y9.n
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/** fOLnK
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* Use the origin page to create a new page >'.[G:b
* @param page K?JV]^
* @param totalRecords s" N\82z)
* @return |
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*/ IF
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publicstatic Page createPage(Page page, int hWm0$v1p
Y=|CPE%V
totalRecords){ G4O3h Y.`
return createPage(page.getEveryPage(), }Wqtip:L
|lY`9-M`I
page.getCurrentPage(), totalRecords); G-ZhGbAI7
} xjE7DCmA
q6Rw4
/** yduuFK
* the basic page utils not including exception }\EL;sT
zNwc((
handler c{ 7<H
* @param everyPage ,,7.=#
* @param currentPage 8ZFH}v@V1'
* @param totalRecords sc9]sIb
* @return page i:{:xKiC a
*/ 4':MI|/my_
publicstatic Page createPage(int everyPage, int l-XnB
g(1"GKg3K
currentPage, int totalRecords){ y1nP F&_
everyPage = getEveryPage(everyPage); yZ ?$8r
currentPage = getCurrentPage(currentPage); 2G H)iUmc
int beginIndex = getBeginIndex(everyPage, "7:u0p!
qR_SQ
VN
currentPage); 3eJ\aVI>pE
int totalPage = getTotalPage(everyPage, fG3wc
l~
" xlJs93c
totalRecords); BL7>dZOa
boolean hasNextPage = hasNextPage(currentPage, MV9r5 |3-
~R)1nN|
totalPage); Nz}|%.GP"
boolean hasPrePage = hasPrePage(currentPage); 4bE42c=Ca7
OW?uZ<z
returnnew Page(hasPrePage, hasNextPage, FXcc1X/
everyPage, totalPage, 6<#Slw[
currentPage, [1e.i
B5D3_iX]
beginIndex); ybC-f'0
} mSy|&(l
87R%ke
privatestaticint getEveryPage(int everyPage){ coW)_~U|
return everyPage == 0 ? 10 : everyPage; Hi$#!OU
} t2~"B&7My
!'+\]eA
privatestaticint getCurrentPage(int currentPage){ X #&(~1O
return currentPage == 0 ? 1 : currentPage; p!C_:Z5i
} QziN]
5aa}FdUq
privatestaticint getBeginIndex(int everyPage, int \dC.%#
?0? x+
currentPage){ v`@5enr
return(currentPage - 1) * everyPage; ys:1Z\$P
} !."Izz/
7YoofI
privatestaticint getTotalPage(int everyPage, int ^-
u[q-
!
lO%MyP
totalRecords){
~JAH-R
int totalPage = 0; LZgwIMd
(7M^-_q]D
if(totalRecords % everyPage == 0) PWADbu{+
totalPage = totalRecords / everyPage; +8L(pMI4
else AN|jFSQ'
totalPage = totalRecords / everyPage + 1 ; .CIbpV?T
45]Ym{]
return totalPage; =x|##7
} aeN}hG
Oex{:dO "F
privatestaticboolean hasPrePage(int currentPage){ sURUQ H
return currentPage == 1 ? false : true; <1;,B%_^
} Zm"!E6`69
Zkwy.Hq^
privatestaticboolean hasNextPage(int currentPage, jx^|2
7j9D;_(.^$
int totalPage){ T%M1[<"Q
return currentPage == totalPage || totalPage == F'$9en2I:
I!C(K^
0 ? false : true; GC5#1+fQ
} xiOv$.@q
@m !9"QhC
BN<#x@m$]
} w7=D6`
&0;{lS[N:L
-s?dzX
J4Q)`Y\~
C,sD?PcSi+
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 v*C+U$_3\1
r|
6S
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 w@gl
89:?.'
做法如下: |k['wqn"
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象
s+y'<88
Egjk^:@
的信息,和一个结果集List: cEh0Vh-]
java代码: Q G=-LXv:@
.g(\B
XNkQk0i;g&
/*Created on 2005-6-13*/ q N[\J7Pz9
package com.adt.bo; E7Gi6w~\
~u~[E
import java.util.List; 5CRc]Q#@
'
q=NTP
import org.flyware.util.page.Page; 61s2bt#
#(26t _a
/** &bS"N)je
* @author Joa r[UyI3(i^
*/ N18diP[C
publicclass Result { f!uA$uLc
>H=Q$gI
private Page page; U4^p({\|-
xi1N?
pP
private List content; W O+?gu
Z@c0(ol
/** 3wa<,^kqy
* The default constructor &[W3e3Asra
*/ QU,TAO
public Result(){ HhY2`P8
super(); upEPv
.h
} H[_uVv;}6
Fy(nu-W
/** \{+nXn
* The constructor using fields 3q.[-.q
* BhE~k?$9
* @param page S\{^LVXTMd
* @param content VATXsD
*/ &"H<+>`
public Result(Page page, List content){ qqom$H<
this.page = page;
Vf,~MG
this.content = content; OCOO02Wq1
} bh;b`
5
q:~`7I
/** EB3o8
* @return Returns the content. ixJ20A7
*/ ,TfI
publicList getContent(){ Er)_[^)
HG
return content; m^oi4mV
} I}G}+0geV
g`5`KU|
/** J!K/7uS
* @return Returns the page. }^Ua
*/ s=%+o&B
public Page getPage(){ {+UNjKQC
return page; IIt^e#s&
} { d2f)ra.
.jGsO0
/** cT=wJ
* @param content E[Ws} n.
* The content to set. %_@5_S
*/ HfeflGme*
public void setContent(List content){ ";Ig%]
this.content = content; uI-76
} k\thEEVP0*
/HJ(Wt
q
/** *ZSp9g"Z
* @param page 1PTu3o&3
* The page to set. ^(m6g &$(
*/ ?VN]0{JSp
publicvoid setPage(Page page){ QB|fFj58u
this.page = page; $I6eHjYT
} O\8|niW|
} r5qx! >
|KrG3-i3X
Rd1ku=
-S3+
h$Y8
0|>
2. 编写业务逻辑接口,并实现它(UserManager, @G$<6CG\
yjFQk,A
UserManagerImpl) 2"Uk}Yz|
java代码: ~md|k
/,@v"mE7c!
@)'@LF1Z
/*Created on 2005-7-15*/ *u4X<oBS*
package com.adt.service;
UoS;!}l
GuY5 %wr
import net.sf.hibernate.HibernateException; pr,1Wp0l
\lakT_x
import org.flyware.util.page.Page; 898wZ{ 9
_5S$mc8K0
import com.adt.bo.Result; H!>oLui
utl=O
/** u,,WD
* @author Joa '=5_u
*/ =bg&CZVT
publicinterface UserManager { iEgM~
g2>u]3&W
public Result listUser(Page page)throws %s :
jMWwu+w
HibernateException; 5a|m}2IX
@#Uiy5N
} :h^UC~[h 3
;xtb2c8HT
mL5f_Fb+
_7"W\gn:9
d?y\~<
java代码: DSZhl-uGM
L=wFo^N
@%G"i:HZ&
/*Created on 2005-7-15*/ 8[`<u[Iv
package com.adt.service.impl; &`Z)5Ww
_"bvT?|
import java.util.List; ',s7h"
"<$vU_
import net.sf.hibernate.HibernateException; $hp?5KM
WM
)g(i~(
import org.flyware.util.page.Page; "57G@NC{n
import org.flyware.util.page.PageUtil; $<e .]`R
JU1; /3(
import com.adt.bo.Result; 6U9Fa=%>}
import com.adt.dao.UserDAO; #( J}xz;
import com.adt.exception.ObjectNotFoundException; =V]i?31[
import com.adt.service.UserManager; QGG(I7{-
A2_3zrE
/** f8jz49C
* @author Joa _H<OfAO
*/ 6Q.whV%y
publicclass UserManagerImpl implements UserManager { Ki;5 =)
vUx$[/<
private UserDAO userDAO; ~cj:AIF
8vo7~6yy
/** c;}n=7,>:L
* @param userDAO The userDAO to set. 5<?$/H|7T
*/ 8&hn$~ate
publicvoid setUserDAO(UserDAO userDAO){ 5MU@g*gj,C
this.userDAO = userDAO; rWKLxK4oU
} L>GYj6D9
h,?Yw+#o"
/* (non-Javadoc) IVODR
* @see com.adt.service.UserManager#listUser
C)}LV
> .~k?_Of
(org.flyware.util.page.Page) J
uKaRR~
*/ 2+cicBD
public Result listUser(Page page)throws [N+ruc?)
pvxqeC9`
HibernateException, ObjectNotFoundException { G)|HFcE
int totalRecords = userDAO.getUserCount(); ~x|Sv4M
if(totalRecords == 0) 8k'em/M~
throw new ObjectNotFoundException tO3B_zC
d0E5 ;3tQ
("userNotExist"); i.,B
0s]Z
page = PageUtil.createPage(page, totalRecords); 481u1
List users = userDAO.getUserByPage(page); 30`H
Xv@
returnnew Result(page, users); a
:AcCd)
} uRhH_c-6C
*9^k^h(r&4
} [T|1 Qq7
!gQ(1u|r
824%]i3
-bQvJ`iF
(XWs4R.mkb
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 aKcV39brr
nwH|Hs riU
询,接下来编写UserDAO的代码: #]^`BQ>
3. UserDAO 和 UserDAOImpl: ^@eCT}p{
java代码: xF0*q
l%/,Ef*3
hUc|Xm
/*Created on 2005-7-15*/ n&&y\?n
package com.adt.dao; THZ3%o=X
l]cQ7g5
import java.util.List; cn{l
%6K
H-lRgJdc
import org.flyware.util.page.Page; i?9Lf
N?:S?p9R@
import net.sf.hibernate.HibernateException; 6h8NrjX
2N#L'v@g=+
/** 2V 'Tt3
* @author Joa U {v_0\ES
*/ Hq8.O/Y"=
publicinterface UserDAO extends BaseDAO { _95tgJ y
ttrp|(
publicList getUserByName(String name)throws ?c*d
z{
E ..[F<5
HibernateException; PX'%)5:q;i
:#;?dMkTY
publicint getUserCount()throws HibernateException; =r8(9:F!
{D8IA3w
publicList getUserByPage(Page page)throws 4mg&H0 !
zvWQ&?&o2
HibernateException; ~ME=!;<_
^&%?Q_]
} J4; ".Y=
-Zh+5;8g
75u*ZMK
0fNBy^(K
`{":*V
java代码: usip>y
7Ll(,i<,C
W`
V
/*Created on 2005-7-15*/ ] $*cmk(Y
package com.adt.dao.impl; Oh: -Y]m=
{3>^nMv@e
import java.util.List; >v{m^|QqB
'7^_$M3$\
import org.flyware.util.page.Page; ?{'Q}%
F=H=[pSe
import net.sf.hibernate.HibernateException; U?>cm`DBP
import net.sf.hibernate.Query; <LE>WfmC
f &|SGD*
import com.adt.dao.UserDAO; JC-L80-
)mU)7@!
/** 0IK']C
* @author Joa 6Jm4?ex
*/ $H}Q"^rs
public class UserDAOImpl extends BaseDAOHibernateImpl C-7.Sa
lF<(yF5
implements UserDAO { Q1rwTg\
dxA=gL2
/* (non-Javadoc) LYKepk
* @see com.adt.dao.UserDAO#getUserByName Kh> ^;`h
|@+
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(java.lang.String) C`ok{SNtUy
*/
7@`(DU`z
publicList getUserByName(String name)throws ~(c<ioIf
b4Z#]o
HibernateException { vgV0a{u"
String querySentence = "FROM user in class +MEWAW[}^
v1:5r
com.adt.po.User WHERE user.name=:name"; w-1CA{"i7
Query query = getSession().createQuery q+z,{K
3k=q>~&@
(querySentence); s=q}XIWK
query.setParameter("name", name); _Nd\Cm
return query.list(); czj[U|eB}=
} Z7(hW,60
_K8-O>I "
/* (non-Javadoc) .{6TX"M
* @see com.adt.dao.UserDAO#getUserCount() I|:*Dy,~
*/ IJ!UKa*o%
publicint getUserCount()throws HibernateException { Qtk'^Fc
int count = 0; |YH1q1l
String querySentence = "SELECT count(*) FROM 2oNlQiE_
=U:iR
user in class com.adt.po.User"; h"[
][
Query query = getSession().createQuery cu
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!nu#r$K(
(querySentence); 5~qr+la
count = ((Integer)query.iterate().next JL<}9K
Th-zMQ4
()).intValue(); fx*Swv%r
return count; S>6APQ-
} Dj[D|%9a
Ouj5NL
/* (non-Javadoc) y&iLhd!p
* @see com.adt.dao.UserDAO#getUserByPage j@9A!5<CCk
:r|dXW
(org.flyware.util.page.Page) ?L_#AdK
*/ t]Vw`z%G
publicList getUserByPage(Page page)throws ,O2Uj3"
g|W~0A@D
HibernateException { -2f0CAh~
String querySentence = "FROM user in class E;%{hAD{
/H\ZCIu/7
com.adt.po.User"; ,"DkMK4%
Query query = getSession().createQuery 1y
6H 2
wLW!_D,/R
(querySentence); 6MZfoR
query.setFirstResult(page.getBeginIndex()) !I:6L7HdwB
.setMaxResults(page.getEveryPage()); olh|.9Kdj}
return query.list(); ?vvjwys@
} i<-#yL5
z]tvy).
} B~z&
"`
7n%QP
BHa!jw_~o
$.v5G>-)3
bE0cW'6r
至此,一个完整的分页程序完成。前台的只需要调用 l'c|I
&Y]
R\6#J0&Y-
userManager.listUser(page)即可得到一个Page对象和结果集对象 >&p_G0-
pp/Cn4"w
的综合体,而传入的参数page对象则可以由前台传入,如果用 $vicxE~-E
^lbOv}C*
webwork,甚至可以直接在配置文件中指定。 AM\`v'I*6
h}.0Ne
下面给出一个webwork调用示例: TqCzpf&&h/
java代码: :;rd!)5
UtY<R
Ktg6 *L/
/*Created on 2005-6-17*/ )J5(M`
package com.adt.action.user; z9E*Mh(NE
E}yl@8g:#
import java.util.List; 5q@o,d
ix,5-j
import org.apache.commons.logging.Log; :QB Wy
import org.apache.commons.logging.LogFactory; c!E+&5|n
import org.flyware.util.page.Page; KK/~W
R /iB
import com.adt.bo.Result; ^+!!:J|ra
import com.adt.service.UserService; ^?w6
import com.opensymphony.xwork.Action; F~z4T/TN%G
>|mmJ4T
/** .z)E
* @author Joa 'd'*4 )]k
*/ E2 #XXc
publicclass ListUser implementsAction{ XP~4jOL]
s:,BcVLx^
privatestaticfinal Log logger = LogFactory.getLog ;IE|XR(
NmVc2V]I
(ListUser.class); mam|aRzd
R8?Xz5
private UserService userService; NgQ {'H[Y
OV^)
N
private Page page; ;}WdxWw4
V] <J^m8
privateList users; @<r;>G
L:j;;9Sp{
/* E*i <P
* (non-Javadoc)
AI/xOd!a
* 9Iy>oV
* @see com.opensymphony.xwork.Action#execute() h{qB\aK
*/ BPwFcT)i!(
publicString execute()throwsException{ 6xvy hg#B
Result result = userService.listUser(page); Em %"]B
page = result.getPage(); 9^x'x@6
users = result.getContent(); &qF
return SUCCESS; Q3'\Vj,S&
} FlgK:=Fmj
UcKpid
/** fMP$o3;
* @return Returns the page. ="JLUq*]s
*/ !*'uPw:l2
public Page getPage(){ Sc`W'q^X
return page; =T|Z[/fto
} Tz:mj
o&-q.;MY
/** 58ev (f
* @return Returns the users. v=RQ"iv8
*/ ^ dM,K
p
publicList getUsers(){ zkA"2dh
return users; ;n?H/(6X8>
} |Rf4^vN
&J,MJ{w6"
/** 2<y!3OeN
* @param page ]KBzuz%
* The page to set. (ylpH`
*/ R bM`"wrZ
publicvoid setPage(Page page){ vdyLwBz:
this.page = page; dX^OV$
} =I-SQI8
:RBp
/** y_;LTCj?
* @param users _
)b:F=4j
* The users to set. 4en[!*
*/ ]hJ#%1
publicvoid setUsers(List users){ z
GhJ
this.users = users; nB[Aw7^|A
} 0hp*(, L
M[g9D
/** cNZuwS~,
* @param userService y 4j0nF
* The userService to set. mQ*:?\@
*/ /r^J8B*
publicvoid setUserService(UserService userService){ A(S =
this.userService = userService; 7Y"CeU-S
} / q*n*j
} _3i.o$GO
xlg 6cO
eZ'J,;
s,!+wHv_8
]>M{Qn*
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, 3C=ON.1eg
IxNY%&* `
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 .'.#bH9K
cy%JJ)sf
么只需要: _ +q.R
java代码: kC"lO'
(U#4j 6Q
A%qlB[!:
<?xml version="1.0"?> $ d? N("L
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Hpo7diBE
$k5mI1~
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ZJlmHlAX
} Wx#"6
1.0.dtd"> yhhW4rz
=B-a]?lM
<xwork> yqi=9NB
~<!b}Hv
<package name="user" extends="webwork- 5Arx"=c
>|1.Z'r/
interceptors"> 0.7*2s-
*.nC'$-2r
<!-- The default interceptor stack name U>PF#@ C/
" lar~
--> 1#9qP~#]'{
<default-interceptor-ref kqxX!
4Y2l]86
name="myDefaultWebStack"/> c
4xh
gb:)t}|
<action name="listUser" >T:
Yp<
%P05k
class="com.adt.action.user.ListUser"> iU]py
<param s
wgn( -
G$FNofQx
name="page.everyPage">10</param> i]oSVXx4WC
<result QbA+\
)xwWig.
name="success">/user/user_list.jsp</result> ozv:$>v@"
</action> vF,\{sgW
B]jN~CO?
</package> J}a 8N.S
46^LPC"x
</xwork> "_dh6naZX
OJ0Dw*K<
KFd !wZ@e
7[aSP5e>T
k=L(C^VP
*tkbC2D
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 'oNY4.[
c@iP^;D
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。 ^,F8 ha
29#&q`J
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 PgZeDUPP
wa/
:JE
g!%C_AI
G ,,c,
lB_&Lq8G
我写的一个用于分页的类,用了泛型了,hoho @w:6m&KL9
NgH"jg-
java代码: *p)1c_
K& /
rzs-
U)mg]o-VE
package com.intokr.util; =<~/U?
=fy~-FN_
import java.util.List; ,#;%ILF4%
2Hltgt,
/** "7Qc:<ww
* 用于分页的类<br> 0{u31#0j
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ^]Mlkd:
* 4'L%Wz[6
* @version 0.01 J`F][ A
* @author cheng :i'jQ<|wZN
*/ 1~X~"M
public class Paginator<E> { )<W6cDx'H+
privateint count = 0; // 总记录数 F=}-ngx8&
privateint p = 1; // 页编号 nU]4)t_o\
privateint num = 20; // 每页的记录数 LZC)vF5
privateList<E> results = null; // 结果 F@=)jrO=$
|/LCwq%
/** 'J*)o<%
* 结果总数 QvB]?D#h
*/ tTa" JXG
publicint getCount(){ ,1>ABz
return count; X[pk9mha
} uYk4qorA
doJ\7c5uU
publicvoid setCount(int count){ MN|8(f5Gs
this.count = count; z>_jC+
} 5|zISK%zHS
?9<byEO%M
/** )dFTH?Mpo
* 本结果所在的页码,从1开始 };m.Y>=)K
* jU
K0?S>
* @return Returns the pageNo. TMsEHd
*/ r+X%0@K
publicint getP(){ 5tyr$P! N
return p; i7^_y3dG
} 7=jeq|&kN
+jk_tPSe
/** Q{9#Am^6w
* if(p<=0) p=1 S].=gR0:
* oe1Dm
* @param p O/;$0`~hY
*/ !M]_CPh]
publicvoid setP(int p){ +bnz%/v
if(p <= 0) Q<]~>cd^
p = 1; DkO>?n:-C
this.p = p; <&&xt
?I.
} nr/^HjMV
m*VM1k V
/** "D V.%7*^
* 每页记录数量 Umwd<o
*/ 3e)3t `
publicint getNum(){ lW F=bz0
return num; gHS;RF9
} I<Vh
Eo,
-QaS/WO_
/** Q+4xU
* if(num<1) num=1 E3N4(V\*
*/ HRF4
R o
publicvoid setNum(int num){ #^IEQZgH
if(num < 1) mtEE,O!+
num = 1; 8YI.f
this.num = num; ,^JP0Vc*
} BS }uv3
<L+D
/** /uSEG<D
* 获得总页数 ,"/<N*vh
*/ oL' :07_
publicint getPageNum(){ gd9ZlHo'Id
return(count - 1) / num + 1; pH&Q]u;O
} pf.T{/%
'ad|@Bh
/** h%kB>E~
* 获得本页的开始编号,为 (p-1)*num+1 G7lC'~}
*/ N"~P` H![x
publicint getStart(){ h[d|y_)f
return(p - 1) * num + 1; IQK__)
} D_E^%Ea&`
Z+"%MkX0
/** ?k4O)?28
* @return Returns the results. lyzMKla"
*/ GiBq1U-Q
publicList<E> getResults(){ )i; y4S
return results; =dbLA ,z9
} 9\W~5J<7
45`Gv
public void setResults(List<E> results){ 7`3he8@ze
this.results = results; BaIh,iu
} ["N>Po
IXp P.d
public String toString(){ L4SvE^2+
StringBuilder buff = new StringBuilder :SSlUl4sU$
ZiDmx-X
(); Rs;,_
buff.append("{"); ?Mp)F2'
buff.append("count:").append(count); Q!>8E4Z
buff.append(",p:").append(p); S<+_yB?
buff.append(",nump:").append(num); (JC -4X_
buff.append(",results:").append dL"$YU9z
n
}lav
(results); vO" $Xw
buff.append("}"); {m}B=u
return buff.toString(); ih1s`CjG
} 7I4G:-V:^
hIa@JEIt
} qv3L@"Ub
rS9*_-NH
M3 8,SH<