Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {rn^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .`(YCn?\
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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 .zTkOkL
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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 f4&;l|R0a
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分页支持类: o-JB,^TE
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java代码: _>;{+XRX[
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package com.javaeye.common.util; i0*Cs#(=h
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import java.util.List; 57O|e/2
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publicclass PaginationSupport { ;mC|>wSZ
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publicfinalstaticint PAGESIZE = 30; {fjBa,o
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privateint pageSize = PAGESIZE; KZa6*,,s
,_s.amL3O{
privateList items; fjY:u,5V_
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privateint totalCount; [j0jAl
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privateint[] indexes = newint[0]; %oquHkX%OJ
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privateint startIndex = 0; *{5/" H5
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public PaginationSupport(List items, int 2%9L'-
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totalCount){ $yq76
setPageSize(PAGESIZE); 5NhAb$q2Y
setTotalCount(totalCount); qq3/K9 #y
setItems(items); ?%#no{9
setStartIndex(0); ]&9=f#k%
} o6:bmKWE
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public PaginationSupport(List items, int [:qJ1^U U
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totalCount, int startIndex){ RGkV%u^
setPageSize(PAGESIZE); f.bw A x
setTotalCount(totalCount); }RKsS3}
setItems(items); TBky+]p@
setStartIndex(startIndex); =#[t!-@
} Q7{{r&|t&
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public PaginationSupport(List items, int W~a|AU8]C
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totalCount, int pageSize, int startIndex){ R3.w")6
setPageSize(pageSize); f`_{SU"3
setTotalCount(totalCount); f9
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setItems(items); w'XSkI_ay
setStartIndex(startIndex); a>9_#_hI
} <:T/hm$
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publicList getItems(){ dLeos9M:
return items; 3x7fa^umR
} 5wha _Yet
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publicvoid setItems(List items){ <#199`R
this.items = items; /q,=!&f2
} D>o u,
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publicint getPageSize(){ r!w*y3
return pageSize; bg_io* K
} Iza;~8dH5
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publicvoid setPageSize(int pageSize){ 5|>ms)[RQ
this.pageSize = pageSize; i)$+#N
} j]`hy"
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publicint getTotalCount(){ uFhPNR2l
return totalCount; bj0<A
} Ciz,1IV
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publicvoid setTotalCount(int totalCount){ (FZ8T39
if(totalCount > 0){ ?<Hgq8J
this.totalCount = totalCount; jC$~m#F
int count = totalCount / O '`|(L
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pageSize; 7y42)X
if(totalCount % pageSize > 0) o?~27
count++; .F2"tt?'
indexes = newint[count]; L{l}G,j<
for(int i = 0; i < count; i++){ -dN`Ok<g
indexes = pageSize * ~l.C-
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i; W$&*i1<a+
} Evqy e;
}else{ L; A#N9
this.totalCount = 0; ^,?>6O
} ="f-I9y
} Io>U-Zd\>
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publicint[] getIndexes(){ O8N1gf;t
return indexes; ~E_irzOFP
} c* ~0R?
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publicvoid setIndexes(int[] indexes){ qW|h"9sr
this.indexes = indexes; ;=E}PbZt2
} HZS.%+2
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publicint getStartIndex(){ m^0 I3;
return startIndex; C8YStT
} +
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publicvoid setStartIndex(int startIndex){ k`]76C7
if(totalCount <= 0) Zy{hYHQ
this.startIndex = 0; k6Vs#K7a
elseif(startIndex >= totalCount) 8wZ
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this.startIndex = indexes w^n&S=E E~
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[indexes.length - 1]; gkq~0/
elseif(startIndex < 0) &e#pL`N
this.startIndex = 0; /R?*i@rvf
else{ G&MO(r}B
this.startIndex = indexes Z![#Uz.z
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[startIndex / pageSize]; \$t{K
} NwQ$gDgu t
} ";jAH GbO
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publicint getNextIndex(){ xdY'i0fh
int nextIndex = getStartIndex() + I$)9T^Ra
wdV)M?
pageSize; 0"+QWh
if(nextIndex >= totalCount) ;- Vs|X
return getStartIndex(); hp}rCy|01
else {!{T,_ J
return nextIndex; ^L
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} D62'bFB^
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publicint getPreviousIndex(){ mUR[;;l
int previousIndex = getStartIndex() - ?duw0SZ
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pageSize; Vhb~kI!x
if(previousIndex < 0) @Eh(GZN
return0; Q&%gpa).W
else zJ ;]z0O
return previousIndex; '-G,7!.,r%
} `Pwf?_2n-
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} Gz8JOl
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抽象业务类 (5[#?_~
java代码: 36.mf_AM
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/** 5"q{b1
* Created on 2005-7-12 KpS=oFX{}
*/ <8Z%'C6d
package com.javaeye.common.business; "/UPq6
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import java.io.Serializable; T:CWxusL
import java.util.List; (>Pz3 7
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import org.hibernate.Criteria; `$3P@SO"
import org.hibernate.HibernateException; |Xv\3r
import org.hibernate.Session; ,c;#~y
import org.hibernate.criterion.DetachedCriteria; *|0W3uy\Y
import org.hibernate.criterion.Projections; Z vyF"4QN
import ZC^?ng
*S4&V<W>
org.springframework.orm.hibernate3.HibernateCallback; 6+PP(>em
import +l7Bu} _?
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org.springframework.orm.hibernate3.support.HibernateDaoS m5KLi
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upport; =Q|s[F
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import com.javaeye.common.util.PaginationSupport; pMp@W`i^6
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public abstract class AbstractManager extends pBQ[lPCY/
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HibernateDaoSupport { _F8-4
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privateboolean cacheQueries = false; ~n/:a
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privateString queryCacheRegion; _qQo}|/q
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publicvoid setCacheQueries(boolean u/\Ipk/
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cacheQueries){ {>brue*)
this.cacheQueries = cacheQueries; dQ<e}wtg
} x}reeqn
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publicvoid setQueryCacheRegion(String T16B2|C"Y
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queryCacheRegion){ ^1--7#H
this.queryCacheRegion = 2Paw*"U
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queryCacheRegion; lw4#C`bx
} 6b!1j,\Vx
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publicvoid save(finalObject entity){ '_g*I
getHibernateTemplate().save(entity); Yt4v}{+
} ,l\D@<F
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publicvoid persist(finalObject entity){ VC!g,LU|-
getHibernateTemplate().save(entity); b1ZHfe:
} 2Ju,P_<dt
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publicvoid update(finalObject entity){ Ax!fvcsN
getHibernateTemplate().update(entity); 2L 1Azx
} 8}^ym^H|j
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publicvoid delete(finalObject entity){ ]08~bL1Q
getHibernateTemplate().delete(entity); "xD5>(|^+Q
} r1$x}I#Zv
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publicObject load(finalClass entity, "n<u(m8E
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finalSerializable id){ +OUM 4y
return getHibernateTemplate().load
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(entity, id); HL!" U(_
} #8bI4J{dE
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publicObject get(finalClass entity, ;Y(~'KF
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finalSerializable id){ +
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return getHibernateTemplate().get yXc@i)9w3
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(entity, id); )v.\4Q4
} ]JI
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publicList findAll(finalClass entity){ h3A|nd>\
return getHibernateTemplate().find("from V0:db
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" + entity.getName()); I~c}&'V
} ]PXpzruy
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publicList findByNamedQuery(finalString ve=
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namedQuery){ HSk}09GV
return getHibernateTemplate DRi/<
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().findByNamedQuery(namedQuery); faI4`.i
} w~*"mZaG
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publicList findByNamedQuery(finalString query, _n<
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9}Zi_xK&|e
finalObject parameter){ 8m)E~6
return getHibernateTemplate OB~74}3;
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().findByNamedQuery(query, parameter); <4Cy U
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} {pB9T3ry]
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publicList findByNamedQuery(finalString query, GP}+c8|2
*|:]("i
finalObject[] parameters){ ia/_61%
return getHibernateTemplate {{_,YO^w
4:v{\R
().findByNamedQuery(query, parameters); '
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} & |o V\L
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publicList find(finalString query){ w+tO@
return getHibernateTemplate().find rx;zd ?
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(query); ZsYT&P2
} x68s$H
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publicList find(finalString query, finalObject (*Y ENT}
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parameter){ 6T~xjAuJ3T
return getHibernateTemplate().find SYTzJK@vZJ
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(query, parameter); cj/FqU"
} nyB~C7zR
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public PaginationSupport findPageByCriteria ]7{-HuQ8>}
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(final DetachedCriteria detachedCriteria){ uw@|Y{(K r
return findPageByCriteria jDc5p3D&[]
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); <$
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} Z?-l-sK
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public PaginationSupport findPageByCriteria 1e^-_Bo6'o
(wIpq<%
(final DetachedCriteria detachedCriteria, finalint ouUU(jj02
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startIndex){ {%b-~& F9
return findPageByCriteria th*E"@
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(detachedCriteria, PaginationSupport.PAGESIZE, z '%Vy
];go?.*C
startIndex); XX(;,[(_
} I2'UC)
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public PaginationSupport findPageByCriteria dGzZ_Vf
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(final DetachedCriteria detachedCriteria, finalint :
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pageSize, rB:W\5~7
finalint startIndex){ f"5vpU^5*
return(PaginationSupport) qzqv-{.h
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getHibernateTemplate().execute(new HibernateCallback(){ U{o0Posg
publicObject doInHibernate I.\fhNxHY
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(Session session)throws HibernateException { ( Qw"^lE3
Criteria criteria = j{9sn,<:
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detachedCriteria.getExecutableCriteria(session); T!)v9L
int totalCount = 9_F2nmEv
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((Integer) criteria.setProjection(Projections.rowCount @DrMaTr
x,z +l-y
()).uniqueResult()).intValue(); }CA oB::&
criteria.setProjection >T4.mB7+>
/AP@Bhm
(null); FHI`/
List items = R1FBH:Iu
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criteria.setFirstResult(startIndex).setMaxResults Cv|ya$}a
r"a0!]n
(pageSize).list(); gYx|Na,+
PaginationSupport ps = |[?"$g9v
".eD&oX{
new PaginationSupport(items, totalCount, pageSize, &/4W1=>(
'k#^Z
startIndex);
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return ps; %uyRpG3,
} YZdp/X6x
}, true); ZO+c-!%[(
} ]v3 9ag_hu
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public List findAllByCriteria(final Z| Z447_
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DetachedCriteria detachedCriteria){ |b52JF
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return(List) getHibernateTemplate >9(lFh0P
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().execute(new HibernateCallback(){ QdL
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publicObject doInHibernate /PAxPZf_
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(Session session)throws HibernateException { keEyE;O}u
Criteria criteria = 70l" [Y
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detachedCriteria.getExecutableCriteria(session); h\b]>q@
return criteria.list(); B]q
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} Ym5q#f)|
}, true); {
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} T2
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public int getCountByCriteria(final *?K3jy{
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DetachedCriteria detachedCriteria){ )W~w72j-
Integer count = (Integer) # &o3[.)9
!L+*.k:
getHibernateTemplate().execute(new HibernateCallback(){ |Z<NM#1
publicObject doInHibernate `(?E-~#'
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(Session session)throws HibernateException { H~1*`m
Criteria criteria = -#H>kbs
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detachedCriteria.getExecutableCriteria(session); !j6]k^ra
return NWSBqL5v
q3B#rje>h
criteria.setProjection(Projections.rowCount 0 }k[s+^
ig]*Z
()).uniqueResult(); P'GX-H
} `(<XdlOj
}, true); u<./ddC
return count.intValue(); LZV
} X~GnK>R
} [>Kkj;*
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用户在web层构造查询条件detachedCriteria,和可选的 $$2\qN -
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _=XzQZT!L
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PaginationSupport的实例ps。 0m6Vf
x
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ps.getItems()得到已分页好的结果集 CE:TQzg
ps.getIndexes()得到分页索引的数组 *[(O&L&0
ps.getTotalCount()得到总结果数 +Cl(:kfYB
ps.getStartIndex()当前分页索引 4r`u@
ps.getNextIndex()下一页索引 l2U"4d!o
ps.getPreviousIndex()上一页索引 1g5%Gr/0$5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (Sr&Y1D
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 wP- pFc
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一下代码重构了。 hWwh`Vw%
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我把原本我的做法也提供出来供大家讨论吧: *<#jr
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首先,为了实现分页查询,我封装了一个Page类: h}i
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java代码: Pfu2=2Ra
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/*Created on 2005-4-14*/ g8
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package org.flyware.util.page; RyKsM.
V03U"eI="
/** ttuQ,SD
* @author Joa 4<)%Esyb
* b"t95qlL
*/ iXK.QktHw
publicclass Page { ilEWxr;,
3:7J@>
/** imply if the page has previous page */ qP6]}Aj]
privateboolean hasPrePage; :TqvL'9o
j{SRE1tqh
/** imply if the page has next page */ {$)zC*l
privateboolean hasNextPage; r5> FU>7'
_?kjIF
/** the number of every page */ p<*3mbgGO
privateint everyPage; -gefdx6ES
$]Kgs6=r
/** the total page number */ Ol6jx%Je`
privateint totalPage; os|8/[gT
XYhN;U}Z
/** the number of current page */ at]=SA
privateint currentPage; >{p&_u.r-
mk8xNpk B
/** the begin index of the records by the current }&Un8Rg"h
G
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query */ bO>q`%&
privateint beginIndex; ^EWkJW,Yc
:#1{c^i%3
z$$ E7i
/** The default constructor */ >Lx,<sE
public Page(){ q 9lz
]l7) F-v
} kg?[
R7}=k)U?d@
/** construct the page by everyPage R)MWO5
* @param everyPage %^f!= *
* */ xDv$z.=Y
public Page(int everyPage){ 5A
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this.everyPage = everyPage; [74HUw>
} c""*Ng*T
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/** The whole constructor */ =/Pmi_
public Page(boolean hasPrePage, boolean hasNextPage, v=e`e68U~
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int everyPage, int totalPage, {I0b%>r=
int currentPage, int beginIndex){ +?Vj}p;
this.hasPrePage = hasPrePage; q&OF?z7H
this.hasNextPage = hasNextPage; u+%Ca,6
this.everyPage = everyPage; /~[+'
this.totalPage = totalPage; $mOVo'2
this.currentPage = currentPage; /|V!2dQs"
this.beginIndex = beginIndex; (|+Sbq(o
} huFT_z_;;
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/** Uyf<:8U\
* @return L[o;@+32
* Returns the beginIndex. /RU'~(
*/ qpzzk9ba[
publicint getBeginIndex(){ GSo&$T;B6
return beginIndex; l]t9*a]a
} d5h]yIz^
3<.]+ukm
/** (?R;u>
* @param beginIndex )@+lfIE(l
* The beginIndex to set. VWDXEa9
*/ ^Z1t'-xZ
publicvoid setBeginIndex(int beginIndex){ j06?Mm_c2
this.beginIndex = beginIndex; &AM<H}>
} 7R9.g6j
qNb|6/DG
/** kHLpa/A
* @return +@*}_%^l"
* Returns the currentPage. P7ktr?V0a
*/ 9D@
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publicint getCurrentPage(){ mG4$
return currentPage; .,Qj3
} {p3VHd#
/]7FX"
/** Mx?]7tI
* @param currentPage y.,S}7l:
* The currentPage to set. /){F0Zjjt
*/ |^!#x Tj
publicvoid setCurrentPage(int currentPage){ XfY~q~f8
this.currentPage = currentPage; EC9D.afy&
} u\LG_/UJV1
"9F]Wv/
/** &q~**^;'
* @return }#0MJ6L
* Returns the everyPage. 4HXqRFUD
*/ |]=. ^
publicint getEveryPage(){ YdsY2
return everyPage; LF o{,%B
} 'lmZ{a6
DXX(q k)6
/** xW|^2k
* @param everyPage 7C~qAI6Eg
* The everyPage to set. fDe4 [QQ8
*/ P(iZGOKUs=
publicvoid setEveryPage(int everyPage){ CbPCj.MH
this.everyPage = everyPage; 0LI:R'P+P[
} 2K >tI9);
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/** %1f, 8BM
* @return Ve/"9?Y_
* Returns the hasNextPage. w\(LG_n|
*/ V[E7mhqy
publicboolean getHasNextPage(){ 6 0C;J!D
return hasNextPage; n =SY66
} jC_7cAsl
bOIVe
/** g;p]lVx=>
* @param hasNextPage VrG4wLpLs
* The hasNextPage to set. 8R!3}kx
*/ !r=^aa(\
publicvoid setHasNextPage(boolean hasNextPage){ X`xI~&t_
this.hasNextPage = hasNextPage; Z)iRc$;
} r]! <iw
7\ .Ax
/** PT2b^PP
* @return "= H.$
+
* Returns the hasPrePage. E>_?9~8Mf
*/ }qf9ra
publicboolean getHasPrePage(){ t<`h(RczHI
return hasPrePage; In1VW|4h
} *7L*:g
/D9FjOP
/** Rg:3}T`~n
* @param hasPrePage }h+_kRQ
* The hasPrePage to set. TWv${m zE
*/ 2m`4B_g A
publicvoid setHasPrePage(boolean hasPrePage){ :V)W?~Z7B
this.hasPrePage = hasPrePage; ?(8z O"
} 8 I'1~d%$
XTIRY4{
d
/**
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* @return Returns the totalPage. R'E8>ee;^
* qF9rY)ifm
*/ 7Pt*V@DHS
publicint getTotalPage(){ $D,m o2I
return totalPage; doR'E=Z4h
} tykA69X\W
pB
@l+
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/** 6{O#!o*g
* @param totalPage |
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* The totalPage to set. tE)%*z@<Lt
*/ xx}R6VKU.
publicvoid setTotalPage(int totalPage){ " mKMym2
this.totalPage = totalPage; x,9fOA
} E)(`Z0
] o!#]]
} j/zD`ydj
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5io7!%
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 NJYx.TL
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个PageUtil,负责对Page对象进行构造: gbc^Lb
java代码: ^q"wd?((h
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M/U$x /3K
/*Created on 2005-4-14*/ ivdw1g|)h
package org.flyware.util.page; y$)gj4k/D
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import org.apache.commons.logging.Log; &`rV{%N"
import org.apache.commons.logging.LogFactory; nsyg>=j
0/.#V*KM
/** >Kl78w:
* @author Joa V07x+ovq
* <_*8a(j3
*/ ;WIL?[;w
publicclass PageUtil { 0w >DU^+
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privatestaticfinal Log logger = LogFactory.getLog Q^Ln`zMe
?`F")y
(PageUtil.class); TJtW?c7
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/** }iy`Ko+B"b
* Use the origin page to create a new page $ql-"BB
* @param page _ED1".f
* @param totalRecords (.,E6H|zI
* @return }nE#0n
*/ )Jx!VJ^Y
publicstatic Page createPage(Page page, int @ ADY?
XA])<dZ
totalRecords){ +DKrX
return createPage(page.getEveryPage(), |Y<ca
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page.getCurrentPage(), totalRecords); S&-sl
} sF;1)7]Pq
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/** ?Di,'
* the basic page utils not including exception ?xf59mY7
yZ&By?.0
handler [ hj|8)
* @param everyPage w8%yX$<
* @param currentPage F *;
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* @param totalRecords +Z XGT
* @return page hBsjO3n
*/ whNRUOK:
publicstatic Page createPage(int everyPage, int 4\(;}M-R{
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currentPage, int totalRecords){ kyJv,!};
everyPage = getEveryPage(everyPage); wrG*1+r
currentPage = getCurrentPage(currentPage); 7kn=j6I
int beginIndex = getBeginIndex(everyPage, {CH\TmSz
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currentPage); #py7emu
int totalPage = getTotalPage(everyPage, P7\(D`
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totalRecords); se_zCS4Y
boolean hasNextPage = hasNextPage(currentPage, ^F?H)[0
$!I$*R&
totalPage); iy
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boolean hasPrePage = hasPrePage(currentPage); MbnV5 b:X
zi>f436-
returnnew Page(hasPrePage, hasNextPage, 62EJ# q[
everyPage, totalPage, [ur/`
currentPage, -lL*WA`
+:&(Ag
beginIndex); 3:Co K#
} D .Cm&
lO,
2
privatestaticint getEveryPage(int everyPage){ j<deTK;.
return everyPage == 0 ? 10 : everyPage; b&~uK"O'7d
} #Mbt%m
!^axO
privatestaticint getCurrentPage(int currentPage){ #bu`W!p}
return currentPage == 0 ? 1 : currentPage; mKpUEJ<a
} k5-mK{RZ
>\DXA)nc
privatestaticint getBeginIndex(int everyPage, int qUtVqS
XQ(`8Jl&^
currentPage){ rvE!Q=y~
return(currentPage - 1) * everyPage; >^J!Z~;L)
} lYw A5|+
<Mc:Cg8>
privatestaticint getTotalPage(int everyPage, int *7*g!
km
\f66ipZK*
totalRecords){ g8kw|BgnL
int totalPage = 0; /LSiDys
66L*6O4
if(totalRecords % everyPage == 0) SgXXitg9+
totalPage = totalRecords / everyPage; [RpFC4W
else p'w[5'
totalPage = totalRecords / everyPage + 1 ; [F/x U
9: ~,TH
return totalPage; n;rOH[P
} F$ h/k^
McsqMI6
privatestaticboolean hasPrePage(int currentPage){ * n!0
return currentPage == 1 ? false : true; X<9DE!/)
} VDnAQ[T@d
V$v;lvt^Uq
privatestaticboolean hasNextPage(int currentPage, [/#n+sz.A
%7|qnh6
int totalPage){ 3b&W=1J
return currentPage == totalPage || totalPage == 5h{Hf]A
LnJ7i"Q
0 ? false : true; coLn};W2
} 0>e>G (4(8
P;_dilG
}p- %~Y
} SbI,9<
S?3{G@!
k6Tpaf^
!m(6/*PAl
kT$4X0}
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 H>7!+&M
SiBbz4
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 3:;%@4f
b6/:reH{
做法如下: Fk9(FOFg
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /Cg/Rwl
F 1zc4l6
的信息,和一个结果集List: 9MYt4
java代码: 3p4bOT5
b5)>h
i{e<kKh
/*Created on 2005-6-13*/ PRah?|*0s
package com.adt.bo; 33;|52$
;q^YDZ'
import java.util.List; kXj pCtCu
sIy$}_
import org.flyware.util.page.Page; AMm O+E?
#&5\1Qu
/** r=[}7N
* @author Joa aEM#V
*/ &GZR-/
publicclass Result { O~Fk0}-
-"nYCF
private Page page; G7=8*@q>:
a #0{tZd
private List content; h n]6he
'{u#:TTj
/** kg@J.
* The default constructor O71rLk;
*/ }N|/b"j9
public Result(){ e.kt]l
super(); {r}}X@|5
} v}mmY>M%
2bC%P})m
/** PJ.jgN(r
* The constructor using fields pxC5a i
* f
0#V^[%Q
* @param page r 1a{Y8?
* @param content j,-7J*A~
*/ F>Oh)VL,Ev
public Result(Page page, List content){ ~VGK#'X:
this.page = page; Cwh;+3?C|
this.content = content; |S}*M<0
} gjWH
}(K
a[!d)Y:zx
/** ;7A,'y4f
* @return Returns the content. c,fedH;
*/ [aC9vEso!
publicList getContent(){ atAA[~
return content; ;(,Fe/wvC
} aRwBxf
'ng/A4
/** vJ'
93h
* @return Returns the page. LYFvzw>M
*/ -XyuA:pxx
public Page getPage(){ /Rz,2jfRx'
return page; tSYnc7
} ]mh+4k?b
]>,|v,i
=
/** ]z%9Q8q'
* @param content f$'D2o, O
* The content to set. `ouzeu9}
*/ c2f$:XiM
public void setContent(List content){ &40]sxm
this.content = content; ~e8n yB
} c 1GP3
f#nmr5F
/** u"T^DrRlQ
* @param page HXQrtJ
* The page to set. q Q'@yTVN
*/ N-|Jj?c
publicvoid setPage(Page page){ bW|y -GM
this.page = page; O5?Eb
} 1hWz%c|
} ?rDwYG(u]@
3"n8B6
"lZ<bG
jFv<]D%A[
Uy:.m
2. 编写业务逻辑接口,并实现它(UserManager, ?0a 0 R
UXJl;Mb
UserManagerImpl) t_dg$KB
java代码: 9="sx 8?
:
eFc.>KoD
#w@Pa L iS
/*Created on 2005-7-15*/ aB)DX
package com.adt.service; Z(eSnV_RL
xW4+)F5P(
import net.sf.hibernate.HibernateException; sCl,]g0{
SI9hS4<j
import org.flyware.util.page.Page; 0Kk*~gR?
QEKFuY<E+
import com.adt.bo.Result; bl<7[J.
z;fSd
/** R2`g?5v
* @author Joa (^9M9+L[i
*/ ;I'/.gW;{
publicinterface UserManager { nL!@#{z
B vc=gW
public Result listUser(Page page)throws %5gJ6>@6Z
M(uB
;Te
HibernateException; ZB&Uhi
Rp*t"HSaAW
} ?<QFW#:)
'4sD1LD~}
*Rh .s!@4
!.$P`wKr
UD`Z;F
java代码: JrTBe73.]j
cx(F,?SbS
CF"3<*%x
/*Created on 2005-7-15*/ 9m4rNvb
package com.adt.service.impl; s=
fKAxH
@#c6\$
import java.util.List; m!g8@YI
J|24I4
import net.sf.hibernate.HibernateException; iXRt9)MT{
%Qz`SO8x?
import org.flyware.util.page.Page; ;%alZ
import org.flyware.util.page.PageUtil; v6\2mc.
3+5\xRq
import com.adt.bo.Result; Yj\yO(o/
import com.adt.dao.UserDAO; 66^t[[
import com.adt.exception.ObjectNotFoundException; ^)l@7XxD
import com.adt.service.UserManager; @|Bp'`j%J
eE%yo3
/** _|:bac8pL
* @author Joa U&$]?3?
*/ pw yl,A
publicclass UserManagerImpl implements UserManager { \#,#_
"Cj#bUw
private UserDAO userDAO; i6 ?JX@I
guXpHF=
/** {OrE1WHB
* @param userDAO The userDAO to set. *AR<DXEL
*/ Ki6.'#%7
publicvoid setUserDAO(UserDAO userDAO){ NV4W2thYo
this.userDAO = userDAO; >%dAqYi $
} ibs"Iv34
(1j$*?iGA
/* (non-Javadoc) L"6/"L
* @see com.adt.service.UserManager#listUser SfSEA^@|
\<x_96jt!\
(org.flyware.util.page.Page) #@s~V<rW
*/ <" l;l~Y1
public Result listUser(Page page)throws wg_CI,Kq
t>@3RBEK
HibernateException, ObjectNotFoundException { d|+jCTKS
int totalRecords = userDAO.getUserCount(); _hL4@C
if(totalRecords == 0) gr{Sh`Cm-
throw new ObjectNotFoundException 3|r!*+.
.OS?^\
("userNotExist"); *"{Z?< 3
page = PageUtil.createPage(page, totalRecords); \1C!,C
List users = userDAO.getUserByPage(page); b\m(0/x
returnnew Result(page, users); -0WCwv
} n12c075
P\6T4s
} ^GaPpm
~.`r(
Ny7=-]N4{"
nL07^6(
OVSq8?L
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 &\`a5[
QN&^LaB<T
询,接下来编写UserDAO的代码: =1OAy`8
3. UserDAO 和 UserDAOImpl: E(kb!Rz
java代码: p<fgUVR
7"NJraQ6
:fKz^@mY4
/*Created on 2005-7-15*/ YkAWKCOni
package com.adt.dao; `Mp7})
M#=5u`h
import java.util.List; ~2DV{dyj
a;T[%'in
import org.flyware.util.page.Page; 7oLf5V1~
}\L!;6oy
import net.sf.hibernate.HibernateException; yxWMatZ2
=,8Eo"~\
/** b<V./rWIB
* @author Joa nEcd+7(
*/ @&xaaqQ-
publicinterface UserDAO extends BaseDAO { L0|hc
c1A G3Nb
publicList getUserByName(String name)throws z<vO#
=/QU$[7X(
HibernateException; 9f%y)[ \
O0(Q0Ko
publicint getUserCount()throws HibernateException; F@'rP++4
{%~4RZA
publicList getUserByPage(Page page)throws C
3XZD4.2
#Q7x:,f
HibernateException; "~2#!bK7
5~%,u2
} A1t~&?
p vQK6r
>g"M.gW
[gns8F#H\
Y0fO.k#C^
java代码: !a&SB*%^I3
#!u51P1
$EGRaps{j>
/*Created on 2005-7-15*/ V]kGcS}
package com.adt.dao.impl; VMye5 P
LSu^#B
import java.util.List; :Ip:sRz
jM1%6
import org.flyware.util.page.Page; 1LId_vJtJ
m_Ac/ctf
import net.sf.hibernate.HibernateException; Ao,!z
import net.sf.hibernate.Query; O][Nl^dl
i$^B-
import com.adt.dao.UserDAO; Q$h:[_v
mV*/zWh_
/** 8u'O`j
* @author Joa 5+/b$mHZX
*/ kAB+28A
public class UserDAOImpl extends BaseDAOHibernateImpl *xo;pe)9
'tu@`7*
implements UserDAO { /sT
^lf=
^g-t#O lD?
/* (non-Javadoc) 7}cDGdr
* @see com.adt.dao.UserDAO#getUserByName ?9gTk
\s?R
1^f.5@tV
(java.lang.String) =1
BNCKT<
*/ %X"m/4c8}
publicList getUserByName(String name)throws E_D ^O
]dbSa1?
HibernateException { 0+<eRR9-
String querySentence = "FROM user in class ta4JWllf
(YYj3#|
com.adt.po.User WHERE user.name=:name"; 8lWH=kA\
Query query = getSession().createQuery :9F''f$AP
'LbeL1ca
(querySentence); 9sU+IT K4
query.setParameter("name", name); pgd8`$(Q
return query.list(); RE>ks[
} %t~SOkx
b WbXh$
/* (non-Javadoc) E<<p_hX8R
* @see com.adt.dao.UserDAO#getUserCount() U7B/t3,=U
*/ .-KtB(t
publicint getUserCount()throws HibernateException { v"~Do+*+
int count = 0; "<w2v'6S
String querySentence = "SELECT count(*) FROM M .)}e7
`/w\2n
user in class com.adt.po.User"; R{)
Q1~H=q
Query query = getSession().createQuery hY=w|b=Y
Rj}o4s2x
(querySentence); 4g7ja
count = ((Integer)query.iterate().next ran^te^Ks(
0Ws;|Yg
()).intValue(); Z%+BWS3YqY
return count; a4T~\\,dZ>
} HUJ|-)"dw
Lvi[*une|
/* (non-Javadoc) %-#
qO
* @see com.adt.dao.UserDAO#getUserByPage kYxl1nv
@q&|MMLt
(org.flyware.util.page.Page) y7JZKtsFA
*/ !6zyJc@01
publicList getUserByPage(Page page)throws cGE=.
\T`["<
HibernateException { Re*|$r#
String querySentence = "FROM user in class l] _b;iux
d/B'[Ur
com.adt.po.User"; jow7t\wk
Query query = getSession().createQuery [IX*sr
s) Cpi
(querySentence); %M{k.FE(
query.setFirstResult(page.getBeginIndex()) Q !9HA[Ly
.setMaxResults(page.getEveryPage()); %5JW<9
return query.list(); v@8S5KJ
} .3VK;au\\
~->Hlxze'K
} {r={#mO;p
J &!B|TS
dQ: ?<zZ
#gh
p/YoTq
l8z%\p5cR
至此,一个完整的分页程序完成。前台的只需要调用 Ko#4z%Yq
z!fdx|PUX
userManager.listUser(page)即可得到一个Page对象和结果集对象 u(W^Nou/+
c~P)4(udT
的综合体,而传入的参数page对象则可以由前台传入,如果用 W_^>MLq
ajW[eyX
webwork,甚至可以直接在配置文件中指定。 nV'3sUvR#
[#p&D~Du&
下面给出一个webwork调用示例: HOE2*4r
java代码: ibvJWg
{G]?{c)"
Qi_&aU$>lM
/*Created on 2005-6-17*/ {|s/]W
package com.adt.action.user; >):m-I
mA&=q_gS
import java.util.List; W.^Ei\w/t
Cz_AJ-WR
import org.apache.commons.logging.Log; D9~}5
import org.apache.commons.logging.LogFactory; OCCEL9d
import org.flyware.util.page.Page; EYG"49
c
!g8*r"[UJ
import com.adt.bo.Result; huz86CO
import com.adt.service.UserService; T?>E{1pS
import com.opensymphony.xwork.Action; PdT83vOCE
5O&d3;p'
/** [FGgkd}
* @author Joa Y;} 2'"
*/ yz?q(]
publicclass ListUser implementsAction{ jZRh KT
KxY$PgcC
privatestaticfinal Log logger = LogFactory.getLog e#.\^
E#8_hT]5
(ListUser.class); gI)u}JX
+ 3h`UF
private UserService userService; "%VbI P
V]rhVMA
private Page page; ;1v=||V
hyfR9~
privateList users; wxj>W[V
cf)J )
/* t:>x\V2m
* (non-Javadoc) y_*n9
)Ct
* 7F9;Su3.
* @see com.opensymphony.xwork.Action#execute() `)$`-Pw*
*/ B| tzF0;c
publicString execute()throwsException{ SET-8f
Result result = userService.listUser(page); Txo@U
page = result.getPage(); c5("-xB
users = result.getContent(); ~b Rd)1
return SUCCESS; 3qtr9NI
} vf<UBa;Xm
M ?*Tf&
/** 34ha26\np
* @return Returns the page. vIVr@1S
*/ 9x?B5Ap[
public Page getPage(){ }p=g*Zo*C;
return page; <c+K3P'3?
} X8b|]Nr
[SkKz>rC
/** t,h{+lYU
* @return Returns the users. ?g3 ]~;#
*/ P?
(vW&B
publicList getUsers(){ 3;-^YG
return users; (bv,02
} hL!QLiF:
zmiZ]uq
/** ^P?vkO"pB?
* @param page WS:5MI,OL
* The page to set. W`rMtzL5
*/ *"cD.)]#2
publicvoid setPage(Page page){ XK qK<!F
this.page = page; gRAC d&)
} ` H
XEZ|
e3v5,.
/** vc8?I."?
* @param users W8]V
* The users to set. PK4`5uT
*/ jJBnDxsA
publicvoid setUsers(List users){ L\e>B>u
this.users = users; y bQP E/9
} 8:thWGLN
(PRBS\*G
/** }"_j0ax
* @param userService :$g8Zm,y
* The userService to set. Gr: 3{o`
*/ !8R@@,_v
publicvoid setUserService(UserService userService){ }HRK?.Vj:
this.userService = userService; nWJ:=JQ i"
} Tf x :"u
} 5f^>b\8+ |
zN{JJ3-
R J~%0
gg^1b77hT
!VP %v&jKm
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, #? ?%B
PB9/m-\H
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 uP@\#/4u
2r&R"B1`(
么只需要: _w(ln9
java代码: xx)-d,S
pB p#a
?WpenUWk
<?xml version="1.0"?> )R?;M
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ]]BOk
<G~>~L.E
1.0//EN" "http://www.opensymphony.com/xwork/xwork- (qBvoLkF9N
ys'T~Cs
1.0.dtd"> @hif$
LA%bq_>f
<xwork> VK:8 Nk_y
AIRr{Y
<package name="user" extends="webwork- FT89*C)oD
.lN s4e
interceptors"> !bU\zH
Xsuwa-G!5~
<!-- The default interceptor stack name z0bJ?~w,
@;:>G A
--> / nZ;v4
<default-interceptor-ref vq!uD!lr
7dOyxr"H-
name="myDefaultWebStack"/> tX%`#hb?s
k?6z_vu
<action name="listUser" feX^~gM
j1-,Sqi
class="com.adt.action.user.ListUser"> r~7:daG*
<param M4m$\~zf
zj|WZ=1*Wp
name="page.everyPage">10</param> MYLsHIPC
<result '+Xlw
l= }~v
name="success">/user/user_list.jsp</result> IQH[Q9%
</action> bb-q O#E
g(ogXA1
</package> Vj?DA5W`'
+&|S'7&{
</xwork> xV\5<7qk5g
$uDqqG(^
TDt Amk
]N{0:Va@D
Anm=*;*M`
%|"g/2sF[G
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 k\`S
lb1
!CUoHTmB
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 TsQU6NNE
a
W%5~3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 iK()&TNz
>[10H8~bI/
*|#T8t,}n
G?c-79]U
GV.A+u
我写的一个用于分页的类,用了泛型了,hoho h8e757z
w5=tlb
java代码: PVOx`<ng
3)=c]@N0
u3 0s_\
package com.intokr.util; 28.~iw
3AcD,,M>>
import java.util.List; eqAW+Ptx
q'Wr[A40j
/** >rsqH+oL
* 用于分页的类<br> !g!5_|
* 可以用于传递查询的结果也可以用于传送查询的参数<br> qJ4T]FVN
* `D$Jv N
* @version 0.01 9W ^xlid6
* @author cheng ~|ss*`CT
*/ "=/ f$Xf
public class Paginator<E> { _aWl]I){5
privateint count = 0; // 总记录数 ;)AfB#:d
privateint p = 1; // 页编号 >slm$~rv
privateint num = 20; // 每页的记录数 )!BsF'uVQ
privateList<E> results = null; // 结果 a>O9pX
J%lgR
/** )\uO9PB[O
* 结果总数 81LNkE,
*/ nC1zzFFJ
publicint getCount(){ =ONHKF[UJ
return count; ^5GW$
} cvd\/pG)
mLV[uhq
publicvoid setCount(int count){ ) 0 W`
this.count = count; aUHcYc\u
} PxS4,`#~
8I;XS14Q
/** u"1rF^j6k
* 本结果所在的页码,从1开始 s*/ bi
W
* yS(}:'`r
* @return Returns the pageNo. !~]<$WZV
*/ nrm+z"7
publicint getP(){ q#w8wH"
return p; gKz(=
} $d S@y+
zq+o+o>xo
/** d[p;T\?"
* if(p<=0) p=1 ~Nf})U
* 66x?A0P
* @param p $$APgj"|<
*/
HB+|WW t>
publicvoid setP(int p){ EtbnE*S
if(p <= 0) PO:"B6
p = 1; W14F
this.p = p; ,GWNLm\5
} <@wj7\pQ
9,j-Vp!G
/** 8to8!(
* 每页记录数量
X\$ 0
*/ goat<\a
publicint getNum(){ m7EcnQf
return num; E%oY7.~-
}
j~j jX
-=s(l.?Hm5
/** 5DOBsf8Jo
* if(num<1) num=1 n1
6 `y}
*/ 0Wa}<]:^
publicvoid setNum(int num){ G,Z^g|6
if(num < 1) !q"W{P
num = 1; wo_,Y0vfB
this.num = num; 3(TsgP>`
} dL7E<?l
Y!iZW
/** 8k
q5ud
* 获得总页数 !Z
VU,b>
*/ _iNq"8>2
publicint getPageNum(){ ~{sG| ;/!*
return(count - 1) / num + 1; !EUan
} Bqma\1cgb
W>-Et7&2
/** ,h"-
* 获得本页的开始编号,为 (p-1)*num+1 F}Vr:~
*/ 2'=T[<nNB
publicint getStart(){ ifN64`AhRX
return(p - 1) * num + 1; uqz]J$
} }D+}DPL{^
g&/T*L
/** iq(
)8nxi
* @return Returns the results. 6aM*:>C"
*/ rZ8`sIWQt
publicList<E> getResults(){ *m?/O}R
return results; bfo["
} lHgs;>U$
Xpzfm7CB/
public void setResults(List<E> results){ cGjPxG;
this.results = results; ;WR,eI..
} Ft}@1w5
{s. = )0V
public String toString(){ w]N!S;<N
StringBuilder buff = new StringBuilder %|s+jeUDn|
tcxcup%
(); >EY3/Go>
buff.append("{"); vpmj||\-
buff.append("count:").append(count); .\>v0Du
buff.append(",p:").append(p); mI 74x3 [
buff.append(",nump:").append(num); SlsdqP
9
buff.append(",results:").append oudxm[/U
lNSLs"x^
(results); ,VO2a mI
buff.append("}"); 8WnwQ%;m?
return buff.toString(); |sJSN.8
} E>l~-PaZY
9B;{]c
} lg^Z*&(
!47n[Zs
<[w=TdCPs