Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ]]5(:>l
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #X6=`Xe#
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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 EAF\7J*
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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 77 ?TRC
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分页支持类: Gr3 q
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java代码: Q0xQxz
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package com.javaeye.common.util; F-$NoEL
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import java.util.List; ]!@!qp@
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publicclass PaginationSupport { TJ,?C$3
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publicfinalstaticint PAGESIZE = 30; Kke
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privateint pageSize = PAGESIZE; E,4*a5Fi
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privateList items; s2nZW pIy
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privateint totalCount; Y2+YmP*z`
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privateint[] indexes = newint[0]; )P.,h&h/
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privateint startIndex = 0; sr:hRQ27
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public PaginationSupport(List items, int >waA\C}
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totalCount){ -1R7 8(1
setPageSize(PAGESIZE); 2%]#rZ
setTotalCount(totalCount); `Cu9y+t
setItems(items); .;D'
setStartIndex(0); ^brh\M,:@
} oK&G
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public PaginationSupport(List items, int TQ5kT?/{
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totalCount, int startIndex){ Q%t
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setPageSize(PAGESIZE); wJ7Fnj>u%
setTotalCount(totalCount); ASNo6dP7
setItems(items); Lf8{']3
setStartIndex(startIndex); G2J4N2hu
} FWS!b!#,N
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public PaginationSupport(List items, int RLDu5
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totalCount, int pageSize, int startIndex){ ay=f1<a
setPageSize(pageSize); #;'*W$Wk2
setTotalCount(totalCount); ck8Qs08
setItems(items); TG.\C8;vFh
setStartIndex(startIndex); WVL\|y728s
} 57$/Dn
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publicList getItems(){
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return items; QwI HEmdM
}
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publicvoid setItems(List items){ )/{~&LU
this.items = items; A{52T]9X
} 9O:-q[K**
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publicint getPageSize(){ SN#N$] y5s
return pageSize; Vb~;"WABo
} l+O\oD?-
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publicvoid setPageSize(int pageSize){ AE%zqvp>
this.pageSize = pageSize; Ude)$PAe%
} :NWrbfz
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publicint getTotalCount(){ @OC*:?!4
return totalCount; /?6
} ;7!u(XzN
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publicvoid setTotalCount(int totalCount){ w)gMJX/0yw
if(totalCount > 0){ 0-U%R)Q
this.totalCount = totalCount; J5\2`U_FZ
int count = totalCount / Q!W+vh
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pageSize; N3Z6o.k
if(totalCount % pageSize > 0) (m=F
count++; w{Y:p[}
indexes = newint[count]; rVnolA*%
for(int i = 0; i < count; i++){ <P
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indexes = pageSize * mmEe@-lE
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i; XN'<H(G
} U6_GEBz~y
}else{ "J3n_3+
this.totalCount = 0; "ODs.m oq
} &4Y@-;REt
} [b@9V_
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publicint[] getIndexes(){ P Z+Rz1x
return indexes; {hKf
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} &0euNHH;sL
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publicvoid setIndexes(int[] indexes){ J<7nOB}OD
this.indexes = indexes;
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} I~7eu&QZ
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publicint getStartIndex(){ </7?puVR
return startIndex; Dad*6;+N
} [moz{Y
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publicvoid setStartIndex(int startIndex){ 8'Bik
if(totalCount <= 0) {;Y2O.lV
this.startIndex = 0; OW8"7*irT
elseif(startIndex >= totalCount) pkEqd"G
this.startIndex = indexes OYNPZRu
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[indexes.length - 1]; o2NU~Ub
elseif(startIndex < 0) E3o J;E
this.startIndex = 0; /'>#1J|TlK
else{ Klk[h
this.startIndex = indexes Fu#mMn0c
$ ~2qEe.h
[startIndex / pageSize]; ai(J%"D"
} _#6ekl|%
} Y,C3E>}Dq
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publicint getNextIndex(){ _l!TcH+e
int nextIndex = getStartIndex() + +;wu_CQu
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pageSize; <YBA
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if(nextIndex >= totalCount) *ZA.O
return getStartIndex(); H-1y2AQ
else :g=z}7!s
return nextIndex; ^H
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} E;^~}
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publicint getPreviousIndex(){ xQ7-4N,
int previousIndex = getStartIndex() - sDvtk]4o-4
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pageSize; HX:rVHY
if(previousIndex < 0) }[*BC5{>
return0; o w<.Dh
else ]
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return previousIndex; y9L:2f\
} Wo+'j $k
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} SB'$?Kh
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抽象业务类 C@i4[g){
java代码: #x;i R8^
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/** ]MXeWS(
* Created on 2005-7-12 Z6I^HG{:
*/ ~&Gw[Nd1
package com.javaeye.common.business; ngoAFb
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import java.io.Serializable; Q(Dp116
import java.util.List; L0HkmaH
{ f@k2^
import org.hibernate.Criteria; s'/ g:aJ
import org.hibernate.HibernateException; }+8w
import org.hibernate.Session; OJ:iQ
import org.hibernate.criterion.DetachedCriteria; P9aGDma
import org.hibernate.criterion.Projections; "##Ylq( "
import J9
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#{8n<sE
org.springframework.orm.hibernate3.HibernateCallback; EJrn4QOs
import JtrLTo
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org.springframework.orm.hibernate3.support.HibernateDaoS 3,cZ*4('d
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upport; iCYo?>
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import com.javaeye.common.util.PaginationSupport; tOK lCc
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public abstract class AbstractManager extends C4 &1M
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HibernateDaoSupport { P+Ta|-
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privateboolean cacheQueries = false; Q!<b"8V]
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privateString queryCacheRegion; ]#N~r&hmQ
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publicvoid setCacheQueries(boolean v]tbs)x;h
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cacheQueries){ "&ElKy
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this.cacheQueries = cacheQueries; vq~btc.p{&
} ?6gC;B
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publicvoid setQueryCacheRegion(String 9?M><bBX
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queryCacheRegion){ (@H'7 ,
this.queryCacheRegion = )h0F'MzW
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queryCacheRegion; Ih]'OaE
} I-Ya#s#m
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publicvoid save(finalObject entity){ W`KRaL0^
getHibernateTemplate().save(entity); j`Xe0U<
} R&BbXSIDX
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publicvoid persist(finalObject entity){ h9,ui^#d$
getHibernateTemplate().save(entity); {%K(O$H#
} {[
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publicvoid update(finalObject entity){ ROr..-[u
getHibernateTemplate().update(entity); Pd@y+|
} *t'qn
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publicvoid delete(finalObject entity){ t7#C&B
getHibernateTemplate().delete(entity); 8lo /BGxS>
} {BBL`tg60
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publicObject load(finalClass entity, [WDtr8L
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finalSerializable id){ gu[3L
return getHibernateTemplate().load h^h!OQK Q
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(entity, id); .6yC' 3~;o
} jj,Y:
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publicObject get(finalClass entity, 821@qr|`e
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finalSerializable id){ `gIlS^Q
return getHibernateTemplate().get M~Yho".
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(entity, id); ,[rh7_
} t'bzhPQO)f
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publicList findAll(finalClass entity){ *_puW
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return getHibernateTemplate().find("from &}P{w
D=U"L-rRs
" + entity.getName()); t0*JinKI
} @tvAI2W
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publicList findByNamedQuery(finalString )vB,eZq
}|
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namedQuery){ beyC't
return getHibernateTemplate Farcd!}
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().findByNamedQuery(namedQuery); #\kYGr-G)
} %Y"@VcN
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publicList findByNamedQuery(finalString query, Tti]H9g_
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finalObject parameter){ =FkU:q$
return getHibernateTemplate $*ujX,}xG
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().findByNamedQuery(query, parameter); ] 8sVXZ
} Ij_Y+Mnl4:
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publicList findByNamedQuery(finalString query, k\UDZ)TQV
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finalObject[] parameters){ S&jZYq**
return getHibernateTemplate *xxG@h|5n
a)'^'jm)4
().findByNamedQuery(query, parameters); v%|^\A"V
} v%(2l|M
`}/&}Sp
publicList find(finalString query){ VY)!bjW.
return getHibernateTemplate().find n22k<@y
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(query); c0v;r4Jo#j
} Jrp{e("9
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publicList find(finalString query, finalObject 2)DrZI
q| p6UL9
parameter){ sM)n-Yy#9
return getHibernateTemplate().find E9_aNYD
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(query, parameter); LMchNTL
} ZzA4iT=KO
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public PaginationSupport findPageByCriteria %xE\IRlR
)v&r^DR_
(final DetachedCriteria detachedCriteria){ b&BSigrvou
return findPageByCriteria +@),Fk_
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }Wf \\
} 1{B^RR.
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public PaginationSupport findPageByCriteria 9s\;,!b
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(final DetachedCriteria detachedCriteria, finalint lYkm1
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startIndex){ ?[>+'6
return findPageByCriteria wykk</eQ.i
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(detachedCriteria, PaginationSupport.PAGESIZE, 1?\ #hemL
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startIndex); G*_$[| H
} ; ]GSVv:
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public PaginationSupport findPageByCriteria wehZ7eqm
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(final DetachedCriteria detachedCriteria, finalint 5#+G7 'k
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pageSize, G"3)\FEM
finalint startIndex){ o*7`r ~
return(PaginationSupport) Zf~Em'g"3
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getHibernateTemplate().execute(new HibernateCallback(){ ^sxcBG
publicObject doInHibernate |,c\R"8xS
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(Session session)throws HibernateException { Ie(vTP1Cj
Criteria criteria = VmM?KlC
#8P9}WTno.
detachedCriteria.getExecutableCriteria(session); d4h1#MK
int totalCount = n gA&PU
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((Integer) criteria.setProjection(Projections.rowCount M&Aeh8>uX
$i&u\iL
()).uniqueResult()).intValue(); "*O(3L.c-
criteria.setProjection epa)~/sA
fI@4 v\
(null); &UtsI@Mu
List items = {f;]
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criteria.setFirstResult(startIndex).setMaxResults / $7E
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(pageSize).list(); .^BL7
PaginationSupport ps = W$=MuF7R
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new PaginationSupport(items, totalCount, pageSize, Tl9KL%9
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startIndex); g+Z~"O]$M
return ps; &Pu}"M$[MH
} 1:S75~b-`
}, true); JR='c)6:
} b=<xzvy
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public List findAllByCriteria(final :_F$e
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DetachedCriteria detachedCriteria){ 0KknsP7
return(List) getHibernateTemplate /I@nPH<y
)r_zM~jI
().execute(new HibernateCallback(){ |ho|Kl `=
publicObject doInHibernate S7SD$+fX
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(Session session)throws HibernateException { <a_Q1 l
Criteria criteria = Bd8,~8
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detachedCriteria.getExecutableCriteria(session); ^3*k6h[(
return criteria.list(); ,1+AfI
} :Z0m "
}, true); S`ms[^-q*
} &y-(UOqbkP
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public int getCountByCriteria(final tm27J8wPzV
$7%e|0jC
DetachedCriteria detachedCriteria){ }$-;P=k
Integer count = (Integer) T@c{5a
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getHibernateTemplate().execute(new HibernateCallback(){ D&KD5_Sw
publicObject doInHibernate iYE:o{
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(Session session)throws HibernateException { i^LLKx7M&
Criteria criteria = kI5`[\
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detachedCriteria.getExecutableCriteria(session); 78't"2>
return Ys |n9pW
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criteria.setProjection(Projections.rowCount =1' / ?
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()).uniqueResult(); jcNYW_G
} ~5e)h_y
}, true); >q{E9.~b
return count.intValue(); Z/nTI0N{
} A8bDg:G1i
} ;E? Z<3{
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用户在web层构造查询条件detachedCriteria,和可选的 gc|?$aE
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |fYr*8rH
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PaginationSupport的实例ps。 nZ>8r
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ps.getItems()得到已分页好的结果集 </,RS5ukn
ps.getIndexes()得到分页索引的数组 +
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ps.getTotalCount()得到总结果数 ,r<!30~f
ps.getStartIndex()当前分页索引 1p#O(o
ps.getNextIndex()下一页索引 x|
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ps.getPreviousIndex()上一页索引 RL=
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 r=8(n<;Co
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 t#pF.!9=
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一下代码重构了。 (+Ia:D
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我把原本我的做法也提供出来供大家讨论吧: rVU::C+-
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首先,为了实现分页查询,我封装了一个Page类: {Vy2uow0
java代码: &p>VTD
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/*Created on 2005-4-14*/ :q6j{C(
package org.flyware.util.page; f=0U&~
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/** 7GN>o@ t
* @author Joa DIx!Sw7EC
* O6nCu
*/ obYXDj2
publicclass Page { F'eV%g
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/** imply if the page has previous page */ -rC_8.u :
privateboolean hasPrePage; )2
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/** imply if the page has next page */ fQZ,kl
privateboolean hasNextPage; (of=hzT^?
/yRP>CX~
/** the number of every page */ ,{{e'S9cy
privateint everyPage; ;MD6iBD
*AEN
/** the total page number */ @9yY`\"ed
privateint totalPage; }bwH(OOS
DEmU},<S
/** the number of current page */ +k@$C,A
privateint currentPage; g=8}G$su{%
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/** the begin index of the records by the current 9~AAdD
JA .J~3
query */ a>1_|QB.
privateint beginIndex; zq(R !a6
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/** The default constructor */ gEFs4;
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public Page(){ K0681_bp
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} Q?e]N I^
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/** construct the page by everyPage v.wHj@
* @param everyPage ^cQTRO|
* */ )vO?d~x|
public Page(int everyPage){ $kc*~V~
this.everyPage = everyPage; okl*pA)
} /eZ UAxq
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/** The whole constructor */ q-3,p.
public Page(boolean hasPrePage, boolean hasNextPage, Yv}V =O%
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int everyPage, int totalPage, EX]LH({?+L
int currentPage, int beginIndex){ 5~AK+6Za
this.hasPrePage = hasPrePage; r-Nv<oH;
this.hasNextPage = hasNextPage; JqX+vRY;dd
this.everyPage = everyPage; XeGtge/}T
this.totalPage = totalPage; })zYo 7
this.currentPage = currentPage; lwY2zX&%)/
this.beginIndex = beginIndex; t-, =sV
} }3{ x G+,
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/** 6Dx^$=Sa$
* @return =3~u.iq$
* Returns the beginIndex. :cx}I
*/ @Yv+L)
publicint getBeginIndex(){ *3,Kn}ik
return beginIndex; fT:a{
} #M9rt~4
O@$wU9D<
/** ]!v:xjzT
* @param beginIndex @vy{Q7aM
* The beginIndex to set. z?9vbx
*/ BKiyog
publicvoid setBeginIndex(int beginIndex){ F_Pv\?35z
this.beginIndex = beginIndex; g;|3n&
} _A[k&nO!&J
Klw\
/** jB"?iC.
* @return X>0$zE@0
* Returns the currentPage. 2swHJ.d\
*/ B~[}E]WEK
publicint getCurrentPage(){ H<gC{:S
return currentPage; Bu:h_sV D
} W7k0!Grrl
s>A!Egmo
/** m2j&v$
* @param currentPage SHc<`M'+
* The currentPage to set. #osP"~{
*/ z2EZ0vZ
publicvoid setCurrentPage(int currentPage){ -d|Q|zF^x
this.currentPage = currentPage; L)0j&
} b.Yl0Y
1WArgR
/** H%}ro.u
* @return e:&+m `OSH
* Returns the everyPage. ~M>EB6
*/ =\t%U5
publicint getEveryPage(){ m1](f[$
return everyPage; st|;]q9?
} L<GF1I)
~E]ct F
/** E{Gkq:
* @param everyPage A,P_|
* The everyPage to set. dZMOgZ.!yr
*/ fR:BF47
publicvoid setEveryPage(int everyPage){ _ct18nh9
this.everyPage = everyPage; oNkASAd
} V>8)1)dF
"kYzgi
/** UJ}Xa&*H\
* @return ZQ&A'(tt4
* Returns the hasNextPage. %syFHUBw
*/ M9_G
publicboolean getHasNextPage(){ `PV+.V}
return hasNextPage; C4Tn
} p "J^
T7wy{;
/** Lc0U-!{G
* @param hasNextPage [<2#C#P:6
* The hasNextPage to set. BdK2I!mm
*/ ?PMF]ah
publicvoid setHasNextPage(boolean hasNextPage){ CY"iP,nHl
this.hasNextPage = hasNextPage; MS_@
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} mKsTA;
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/** F"#8`Ps>
* @return efK3{
* Returns the hasPrePage. C(ay7
*/ Lq-Di|6q
publicboolean getHasPrePage(){ a\UhOPFF
return hasPrePage; $?Et sf#*'
} YY&3M
cz2guUu
/** ,b&-o?.{
* @param hasPrePage
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* The hasPrePage to set. w2
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*/ ftL>oOz[
publicvoid setHasPrePage(boolean hasPrePage){ *KDT0 ;/s
this.hasPrePage = hasPrePage; "agc*o~!F
} [f_4%Now
rh8.kW-K_
/** Bi!j re
* @return Returns the totalPage. j K!Y-
* 9PU9BYBG
*/ ]m>N!Iu
publicint getTotalPage(){ v7V.,^6+
return totalPage; |Lq -vs?
} /~4wM#Yi8
m]Sv>|
/** 8Wa&&YTB
* @param totalPage oicj3xkw?
* The totalPage to set. +[=yLE#P%
*/ ;yc|=I^
publicvoid setTotalPage(int totalPage){ Tb2Tb2C
this.totalPage = totalPage; RR%[]M#_T
} BQs~>}(V
isdEs k#A.
} Z[(V0/[]
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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 z_Nw%V4kr
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个PageUtil,负责对Page对象进行构造: ^kS44pr\Q
java代码: R)%1GG4
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/*Created on 2005-4-14*/ $'9b,- e
package org.flyware.util.page; +npcU:(Kg
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import org.apache.commons.logging.Log; 2'R&K
import org.apache.commons.logging.LogFactory; EmaVd+Sw
;+) M~2 =
/** 4. &t
* @author Joa Y|s?9'z
* cY}Nr#%s@U
*/ q ;@:,^
publicclass PageUtil { k 5<[N2D|!
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privatestaticfinal Log logger = LogFactory.getLog :%#(<@ {
\~1>%F'op
(PageUtil.class); CoZXbTq
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/** LPg1 G+e
* Use the origin page to create a new page @Ju!|G9z/p
* @param page NwK(<dzG
* @param totalRecords
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* @return m &U
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*/ o9tvf|+z
publicstatic Page createPage(Page page, int -rEg(@S %
t`"]"Re
totalRecords){ `&)khxT/
return createPage(page.getEveryPage(), .] S{T
0@ -3U{Q
page.getCurrentPage(), totalRecords); p'`SYEY@Z
} JG2)-x;9
C ?^si
/** 7R$]BY=
* the basic page utils not including exception O_PKS$sz{
l
)hg!(
handler Hkc:B/6
* @param everyPage 9$9Pv%F:j
* @param currentPage nUAs:Q
* @param totalRecords c'9-SY1'~
* @return page HMUn+kk+
*/ .js@F/Hp
publicstatic Page createPage(int everyPage, int kUl:Yj=&
(I?CW~3#
currentPage, int totalRecords){ b,?@_*qv+
everyPage = getEveryPage(everyPage); hBSci|*f
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, ty8\@l
AT#&`Ew
currentPage); K%Sy~6iD&
int totalPage = getTotalPage(everyPage, 0A~zuK
p'2ZDd=v
totalRecords); -L9I;]:KY
boolean hasNextPage = hasNextPage(currentPage, Ha~g8R&
qlT'gUt=H
totalPage); G3j&8[
boolean hasPrePage = hasPrePage(currentPage); hRn[ 9B
i;1EXM
returnnew Page(hasPrePage, hasNextPage, x5Sc+5?*
everyPage, totalPage, x<
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currentPage, erG;M! 9\
0G(T'Z1
beginIndex); );LkEXC_'
} 1U"Fk3
UMg*Yv%
privatestaticint getEveryPage(int everyPage){ AZmABl
return everyPage == 0 ? 10 : everyPage; Bn7~ p+N
} VQ{.Ls2`Z
=6mnXpM.
privatestaticint getCurrentPage(int currentPage){ `-l,`7e'
return currentPage == 0 ? 1 : currentPage; Kvu0Av-7
} kf3yJP/
W$x'+t5H
privatestaticint getBeginIndex(int everyPage, int H3=U|wr|
S`LS/)
currentPage){ @v1f)(N
return(currentPage - 1) * everyPage; |[k/%
} A7~~{9
E%CJM+r!
privatestaticint getTotalPage(int everyPage, int wvAXt*R
2
{lo
totalRecords){ C<!%VHs
int totalPage = 0; ^cYm.EHI
yqpb_h9
if(totalRecords % everyPage == 0) [u_-x3`
totalPage = totalRecords / everyPage; mdu5aL
else 8^3Z]=(Q
totalPage = totalRecords / everyPage + 1 ; Fe(qf>E
1*_wJ
return totalPage; qDqgU
} r)jj]$0
^-3R+U- S
privatestaticboolean hasPrePage(int currentPage){ LbGyD;#_
return currentPage == 1 ? false : true; 7`^]:t
} `I.Uw$,P
P)?)H]J"
privatestaticboolean hasNextPage(int currentPage, mlgw0
K0xZZ`
int totalPage){ o=`FGowF
return currentPage == totalPage || totalPage == Hu
.e@7
h"S+8Y:1{k
0 ? false : true; Re <G#*^
} 9}`A_KzFx
]KMOLe6(
hSmu"a,S
} D. 2HM
'kW' e
UE4zmIq
h' OLj#H
X0X!:gX
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。 F=C8U$'S
!BHIp7p
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7d0E9t;W
Zy2@1-z6
做法如下: oWVlHAPj
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 fu/v1Nhm
~Tv
%6iaeE
的信息,和一个结果集List: Aj06"ep
java代码: 28L3"c
PjEKZHHz
]XEkQ
/*Created on 2005-6-13*/ &Y2mLPB
package com.adt.bo; GI}h)T
zT|]!',
import java.util.List; .'Vjs2 2
XDvT#(Pu
import org.flyware.util.page.Page; .S&S#}$/]
v_*E:E
/** ".z~c%'
* @author Joa iY~9`Q1E
*/ |9)Q =(
publicclass Result { 'vO+,-
hia_CuY#
private Page page; ;b:Ct <
"1rZwFI0l
private List content; JHN35a+
Pm]6E[zC
/** ^'DrU<o
* The default constructor 24 S,w>j
*/ t@-:e^ v
public Result(){ 'z\K0
super(); y: @[QhV
} vVF#]t b|
4*9y4"
/** rm*Jo|eH`
* The constructor using fields =4
&/Pr
* $l:?(&u
* @param page |y@TI
* @param content I(E1ym
*/ 2 @g'3M
public Result(Page page, List content){ )J+vmY~&
this.page = page; 7\aLK#
this.content = content; 9viQ<}K<
} f<A Bs4w
STp}?Cb
/** VIL #q
* @return Returns the content. kStWsc$;+T
*/ B[F,D
publicList getContent(){ x,"'\=|s*
return content; vB, X)
} ,L&Ka|N0
j'i-XIs
/** GYot5iLg
* @return Returns the page. Zs!)w9y&V
*/ D,+I)-k<
public Page getPage(){ a3]'%kKp
return page; 9PEjV$0E2
} krm&.J
JMN1+:7i
/** ulsr)Ik
* @param content b
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* The content to set. 6Gjr8
*/ NS"hdyA
public void setContent(List content){ [vpZ 3;
this.content = content; @AL,@P/9=
} li\hH d5
& v=2u,]T
/** |r5|IA
* @param page zEJ|;oL
* The page to set. r'fNQJ >
*/ N4"%!.Y
publicvoid setPage(Page page){ !8ub3oj)
this.page = page; =!r9;L,?
} $@q)IK%FDL
} +\9Y;Ny
&O(z|-&| x
b#|M-DmT
|SXMd'<3`Z
z7F~;IB*u
2. 编写业务逻辑接口,并实现它(UserManager, '6u;KIG
I'G$: GX
UserManagerImpl) AEm?g$a
java代码: ;5-Sn(G
kc `Q-
N}
%VsuGA
/*Created on 2005-7-15*/ <pRb#G"
package com.adt.service; J\XYUs
)DuOo83n["
import net.sf.hibernate.HibernateException; ws4a(1
5#+!|S[PK
import org.flyware.util.page.Page; YSk,kU
<T:u&Ic
import com.adt.bo.Result; OUn,URI
R@t?!`f!+
/** UO8#8
* @author Joa Z2`(UbG}
*/ o
<8L,u(U
publicinterface UserManager { $zq`hI!1
9)s=%dL
public Result listUser(Page page)throws MsCY5g
IX;u +B
HibernateException; d_Ll,*J9
30g-J(Zg
} )Z0pU\
V3K
Ab
-uK|<
om$)8'A,l
v"6q!
java代码: ^,'!j/w5
L~SM#?z:ue
HS]|s':
/*Created on 2005-7-15*/ 'x
lK_Z
package com.adt.service.impl; 95>(NwST4
(F~i
import java.util.List; +mE y7qM
OT{wqNI
import net.sf.hibernate.HibernateException; ;OTD1=
ZffK];D
import org.flyware.util.page.Page; 4&~1|B{Z
import org.flyware.util.page.PageUtil; Zz=+?L
v! uD]}
import com.adt.bo.Result; u!?.vx<qy
import com.adt.dao.UserDAO; i1ur>4Ns
import com.adt.exception.ObjectNotFoundException; " GkBX
import com.adt.service.UserManager; phwk0J]2
T?:Vw laE
/** "zL<:TQ"
* @author Joa 2#ND(
*/ B.6gJ2c
publicclass UserManagerImpl implements UserManager { 2ksX6M3kY
IIUoB!`
private UserDAO userDAO; 7qq}wR]]
0RN]_z$;H
/** z%(m:/N70
* @param userDAO The userDAO to set. 1XUsr;Wz
*/ 0sto9n3
publicvoid setUserDAO(UserDAO userDAO){ _a"5[sG
this.userDAO = userDAO; 5Q,#Co
} w_q{C>-cR
_n@#Lufx
/* (non-Javadoc) J7/"8S_#N
* @see com.adt.service.UserManager#listUser 1om :SHw
+'Pf|S
(org.flyware.util.page.Page) p]:5S_$
*/ #GT/Q3{C
public Result listUser(Page page)throws u) y6 $
J,%v`A ~N
HibernateException, ObjectNotFoundException { yYwZZa1
int totalRecords = userDAO.getUserCount(); b;`gxXeL
if(totalRecords == 0) lhva|
throw new ObjectNotFoundException bEyZRG
&z8@ rk|
("userNotExist"); ,]\L\ V
page = PageUtil.createPage(page, totalRecords); NGtSC_~d
List users = userDAO.getUserByPage(page); 7'z{FSS
returnnew Result(page, users); w`&~m:R
} "detDB
s"?Z jV)`
} F\F_">5
f1y3l1/
f/&gR5
vzM8U>M
2Kovvh y#
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 (4o_\&
wP8Wx~Q=
询,接下来编写UserDAO的代码: 4\a K C%5
3. UserDAO 和 UserDAOImpl: 4UT%z}[!
java代码: sxinA8
r ) ;U zd
<R582$( I
/*Created on 2005-7-15*/ {Y6U%HG{{r
package com.adt.dao; WM$}1:O
-61{ MMiA
import java.util.List; pSvRyb.K
/J )MW{;O
import org.flyware.util.page.Page; A-Be}A
3&:Us|}
import net.sf.hibernate.HibernateException; X|fl_4NC>
K?o( zh;
/** rrbD0UzFA
* @author Joa 0+%{1JkJq
*/ GM=r{F
&
publicinterface UserDAO extends BaseDAO { SDt)|s
uOUgU$%zqH
publicList getUserByName(String name)throws UJMM&
AP5[}$TT
HibernateException; T'B4 3Q
PKFjM~J
publicint getUserCount()throws HibernateException; >uT,Z,7O
/5 yjON{
publicList getUserByPage(Page page)throws &u&+:m
X)^eaw]Q0
HibernateException; E7X6Shng
AGu#*,K
} Z>
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kT)[<`p
36"-cGNr{
HR'sMu3
1oU/gm$7\q
java代码: 0%J0.USkM7
9/2VU<
K
AB(WK9o
/*Created on 2005-7-15*/ =2v/f_
package com.adt.dao.impl; z7TMg^9#
Io_bS+
import java.util.List; E$l 4v>iA
#C^)W/dP
import org.flyware.util.page.Page; @A32|p}
fk%W07x!
import net.sf.hibernate.HibernateException; 1OI/!!t1$
import net.sf.hibernate.Query; .5$"qb
?
J]G]
<)
import com.adt.dao.UserDAO; I<E~=
;IyA"C(i
/** En!X}Owh
* @author Joa }@6Tcn1
*/ D!7-(3R
public class UserDAOImpl extends BaseDAOHibernateImpl 4^uQB(}Z
c_"=G#^9@i
implements UserDAO { {BV0Y.O
E;v#'
/* (non-Javadoc) 9u[^9tL+D
* @see com.adt.dao.UserDAO#getUserByName k-it#'ll{x
FgwIOpqE*
(java.lang.String) RW"QUT
*/ vq?Le j
publicList getUserByName(String name)throws 4# +i\H`
WSEw:pln
HibernateException { hK]mnA[Y
String querySentence = "FROM user in class %lsRj)n
7:/gO~gI
com.adt.po.User WHERE user.name=:name"; <|-da&7
Query query = getSession().createQuery T)c<tIr6
,J;Cb}
(querySentence); @!'rsPrI
query.setParameter("name", name); #hMS?F|
return query.list(); 6LRvl6ik
} P{m(.EC_
{$>Pg/
/* (non-Javadoc) _c!$K#Yl{
* @see com.adt.dao.UserDAO#getUserCount() xP{)+$n
*/ t;HM
publicint getUserCount()throws HibernateException { LNNwy:_ !
int count = 0; XXDLbT'J
String querySentence = "SELECT count(*) FROM XrUc`
[L m
user in class com.adt.po.User"; r>ziQq8C&
Query query = getSession().createQuery X!xmto
gN@|lHbU
(querySentence); k~%j"%OB
count = ((Integer)query.iterate().next ~a$h\F'6
L;GkG! g
()).intValue(); OsT|MX
return count; /SW*y@R2l
} '3|fv{I
{ )g
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/* (non-Javadoc) S(^HIJK
* @see com.adt.dao.UserDAO#getUserByPage MCO2(E-
,ZV>"'I:
(org.flyware.util.page.Page) %_@T'!]
*/ c7~'GXxQ2
publicList getUserByPage(Page page)throws U9"(jl/o
9Bao~(j/k
HibernateException { !S~0T!afF
String querySentence = "FROM user in class kqkTz_r|H
Gf=3h4
com.adt.po.User"; b(_f{R7PY
Query query = getSession().createQuery do.AesdXaq
FUVp}>#U
(querySentence); b#nI#!p'
query.setFirstResult(page.getBeginIndex()) xyD2<?dGUb
.setMaxResults(page.getEveryPage()); $c{fPFe-
return query.list(); ~ &<Ls
} g@2KnzD
E1j3c
:2
} bWgRGJqt
${)oi:K@:
5pT8 }?7
p'`?CJq8
r;^%D(
至此,一个完整的分页程序完成。前台的只需要调用 r2*8.j51
\RqH"HqD
userManager.listUser(page)即可得到一个Page对象和结果集对象 hd*GDjmRQ/
eDsB.^|l
的综合体,而传入的参数page对象则可以由前台传入,如果用 xtBu]I)%
Xub*i^(]
webwork,甚至可以直接在配置文件中指定。 KKq%'y)u^
_\8jnpT:
下面给出一个webwork调用示例: #;[0:jU0
java代码: h/Yxm2
kRjNz~g
uBK0+FLL@
/*Created on 2005-6-17*/ ]Twyj
package com.adt.action.user; I_m3|VCa|t
5Gs>rq" #
import java.util.List; [D+,I1u2h
fG d1
import org.apache.commons.logging.Log; ppo0DC\>
import org.apache.commons.logging.LogFactory; 9
JhCSw-<)
import org.flyware.util.page.Page; BRy3D\}
PJ)l{c
import com.adt.bo.Result; ur.krsU
import com.adt.service.UserService; 78\j
import com.opensymphony.xwork.Action; +[R^ ?~VK
O{EPq' x
/** h'HI92; [
* @author Joa DcNp-X40I
*/ 182g6/,
publicclass ListUser implementsAction{ O/U? Wq
HSWki';G
privatestaticfinal Log logger = LogFactory.getLog {+m8^-T
,CI-IR2
(ListUser.class); a>6D3n
W
-g."{|
private UserService userService; A%2B3@1'q
HC}vO0X4
private Page page; \HIBnkj)3n
!?>QN'p.b
privateList users; vV xw*\`<6
74ho=
/* Q}G2f4
* (non-Javadoc) sv!zY= 6
* n5%\FFG0M
* @see com.opensymphony.xwork.Action#execute() $KQ q~|
*/ YKz#,
publicString execute()throwsException{ 9%Tqk"x?
Result result = userService.listUser(page); {i+
o'Lw
page = result.getPage(); s=]NKJaQH
users = result.getContent(); b*Q3j}c Z
return SUCCESS; $/lM %yXe
} D;s%cL`
`#'j3,\6
/** wAw1K 2d
* @return Returns the page. .'&pw}F
*/ c:e3hJ
public Page getPage(){ PZQAlO,
return page; ^.R!sQ
} eKy!Pai
w\MWr+4
/** qTK(sW
* @return Returns the users. .^M#BAt2
*/ R:+'"dBge
publicList getUsers(){ Ge/K.]>i
return users; D+v?zQw
} 8R%<~fq r
SswcO9JCX3
/** &TY74w*
* @param page *RxJ8.G
* The page to set. 1a/C(4_k
*/ 2Mk;r*FT
publicvoid setPage(Page page){ tT!'qL.*
this.page = page; bZ1*:k2
} 7)]boW~Q
AmHj\NX$
/** _7\`xU
* @param users PDPK|FU
* The users to set. :{N*Z }]
*/ "b~C/-W I
publicvoid setUsers(List users){ Pc*lHoVL
this.users = users; .Sn{a}XP4
} rH!sImz,
S9Oz5_x
/** '5Yzo^R;
* @param userService ~h_
_Y>
* The userService to set. NuPlrCy;
*/ :>.{w$Ln%
publicvoid setUserService(UserService userService){ .n1&Jsey
this.userService = userService; lHtywZ@%3
} |YsR;=6wT
} iphC\*F
>vp4R`
{=3A@/vM
gy%.+!4>v`
{h|<qfH
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, },j |eA/W
9c[X[Qc
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 W,NqevXo:
`X5!s
么只需要: >U,&V%y
java代码: ttUK~%wSx
t*9 gusmG
I)V=$r{
<?xml version="1.0"?> g%l ,a3"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork m{Vd3{H40
7H)$NG<U$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ,eBC]4)B6
pe
vXixl
1.0.dtd"> {o5|(^l
k7Bh[ ..!
<xwork> )`rD]0ua;
I4G0!"T+
<package name="user" extends="webwork- LWv<mtuYf
b'\Q/;oz>
interceptors"> Q3tyK{JE
z^U+oG
<!-- The default interceptor stack name +Q u.86dH
M i& ;1!bg
--> ]B,tCBt
<default-interceptor-ref 9 Gd6/2
>lV,K1Z
name="myDefaultWebStack"/> salC4z3
ySr,HXz
<action name="listUser" EW*sTI3
v1 8<~
class="com.adt.action.user.ListUser"> wHbkF#[:i
<param wx*?@f>u^
Q"dq_8\`U
name="page.everyPage">10</param> It[51NMal
<result c'i5,\ #X
gSwV:hm
name="success">/user/user_list.jsp</result> fgd2jr3T
</action> w\acgQ^%e
7.<jdp
</package> a2B71 RT~
4W"A*A
</xwork> \1!Q.V
%`C*8fc&
BQ0?B*yqd
>8_y-74
7A\`
o6MFMA+vi
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 d}4NL:=&
t|i NSy3
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。 OF7hp5
SvM\9
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 qUd7O](b=?
AB'+6QU9k
!^%3
FB[b]+t`D{
LG&BWs!
我写的一个用于分页的类,用了泛型了,hoho D6Ad"|Z
)k=KLQ\b
java代码: :')[pO_FW*
]gq)%T]
Lto*L X
package com.intokr.util; 2&V>pE
fB3Jp~$
import java.util.List; pq{`WgA^
@!P2f
/** <2U@O`
gC
* 用于分页的类<br> { KWVPeh
* 可以用于传递查询的结果也可以用于传送查询的参数<br> G1z*e.+y
* Xj\ToO
* @version 0.01 :cC$1zv@
* @author cheng Q]K` p(
*/ ,,{;G'R|
public class Paginator<E> { ~A=zjkm
privateint count = 0; // 总记录数 W<)P@_+-
privateint p = 1; // 页编号 }*6BaB
privateint num = 20; // 每页的记录数 tVRN3fJH
privateList<E> results = null; // 结果 `3F#k[IR
/Sj~lHh
/** +]%S}<R
* 结果总数 T'5{p
*/ |Mq+QDTTw~
publicint getCount(){ G\gjCp?!
return count; n)kbQ]
} Bu(51wU8
C#U(POA
publicvoid setCount(int count){ qi4P(s-i
this.count = count; Mh7m2\fLbd
} yiZtG#6K{
l
;:IL\*1I
/** cj[b ^Wv:
* 本结果所在的页码,从1开始 Ks%0!X?3q
* `*8}q!.
* @return Returns the pageNo. t neTOj
*/ )aIcA
publicint getP(){ OBAO(Ke
return p; %4*c/ c6
} bCw{9El!K4
?#K.D vGJ
/** *C*ZmC5
* if(p<=0) p=1 n-ffX*zA(
* uE's&H
* @param p 4EqThvI{
*/ }93kHO{
publicvoid setP(int p){ Cb ;6yE)!Z
if(p <= 0) AY/.vyS
p = 1; vXDs/,`r
this.p = p; :lB*km g
} x0<;Rm [u=
.#yg=t1C
/** EsGu#lD2
* 每页记录数量 O@Aazc5K
*/ q|D5
A|)
publicint getNum(){ aS [[
AL
return num; L)JB^cxf
} .t@|2
t$!zgUJ
/** nONuw;K
* if(num<1) num=1 rt+4-WuK>
*/ ~~/,2^
publicvoid setNum(int num){ RAO+<m
if(num < 1) ETHcZ
num = 1; z&%i"IY
this.num = num; m# {'9 |
} xOTvrX
r{R-X3s
/** P~\rP6
;
* 获得总页数 MRLiiIrq,5
*/ B"GC|}N)v
publicint getPageNum(){ ;"MChk
return(count - 1) / num + 1; +dCDk* /m
} 0/Q_%
:
\jC) ;mk
/** 9lYKG^#D
* 获得本页的开始编号,为 (p-1)*num+1 {W,5]-
*/ uFWA] ":is
publicint getStart(){ s%D%c;.|
return(p - 1) * num + 1; # ?2*I2_
} ]Fy'M
ly%^\jW
/** d {!P
c<
* @return Returns the results. , /.@([C
*/ T~]~'+<Pi
publicList<E> getResults(){ {xTq5`&gT
return results; %>
XsKXj
} |*{*tW C1
O\=Z;}<N
public void setResults(List<E> results){ F1yn@a "=J
this.results = results; );0
}
p'h'Cz
_5p$#U`
public String toString(){ `jE[Xt"@
StringBuilder buff = new StringBuilder .Pm5nS
UXct+l
(); .\XRkr'-
buff.append("{"); ]K(a32V CH
buff.append("count:").append(count); ,j%\3g`
buff.append(",p:").append(p); #*.!J zOg
buff.append(",nump:").append(num); ^OY$
W
buff.append(",results:").append }WsPu o
/]U$OP*0
(results); ,l>w9?0Z
buff.append("}"); E'WXi!>7p
return buff.toString(); MJ:c";KCq0
} zVE" 6
mE<_oRM)
} v<1@"9EH
84(Jo_9
(@^9oN~}