Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 C-M_:kQ[U
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 H cmW
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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 _a09;C
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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 Ow0>qzTg
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分页支持类: r1!1u7dr
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java代码: w/@ZPBRo]
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package com.javaeye.common.util; i(~DhXz*T
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import java.util.List; BX_yC=S
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publicclass PaginationSupport { n)yDep]$G
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publicfinalstaticint PAGESIZE = 30; ~'M<S=W
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privateint pageSize = PAGESIZE; b1Vr>:sK47
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privateList items; ixA.b#!1
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privateint totalCount; N7?]eD
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privateint[] indexes = newint[0]; B:h<iU:'D
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privateint startIndex = 0;
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q,Gymh;
public PaginationSupport(List items, int <::lfPP
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totalCount){ [}szM^
setPageSize(PAGESIZE); jPSVVOG
setTotalCount(totalCount); \2@J^O1,
setItems(items); Q6m8N
setStartIndex(0); q|*^{(tWs
} $0$sM/ %
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public PaginationSupport(List items, int 0AHQ(+Ap
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totalCount, int startIndex){ ^PEw#.WG
setPageSize(PAGESIZE); [ar0{MPYd
setTotalCount(totalCount); .B]l@E-u
setItems(items); biHacm
setStartIndex(startIndex); G*IP?c>=
} }Xj25` x
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public PaginationSupport(List items, int _(-jk4 L
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totalCount, int pageSize, int startIndex){ !(lcUdBd
setPageSize(pageSize); Zv!`R($
setTotalCount(totalCount); zRna=h!
setItems(items); i"&FW&W
setStartIndex(startIndex); .D@J\<,+l
} q-! H7o
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publicList getItems(){ NQ`D"n
return items; sD3ZZcy|=
} ZWkRoJXNi
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publicvoid setItems(List items){ 8>YF}\D V
this.items = items; 1<ag=D`F_"
} ^+x?@$rq
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publicint getPageSize(){ * zp tbZ
return pageSize; t5{P'v9J
} @v2<T1UC
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publicvoid setPageSize(int pageSize){ { b$"SIg1E
this.pageSize = pageSize; {R_>KE1
} TAXsL&Tz>
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publicint getTotalCount(){ -;9
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return totalCount; J+/}m}bx
} Y(Oh7VwY*P
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publicvoid setTotalCount(int totalCount){ c|/HX%Y
if(totalCount > 0){ o-6d$c}{f
this.totalCount = totalCount; BpIyw
int count = totalCount / ?Ek)" l
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pageSize; D|q~n)TW5
if(totalCount % pageSize > 0) `n$Ak5f
count++; Z1 Nep!
indexes = newint[count]; k|-\[Yl .
for(int i = 0; i < count; i++){ 6\8d6x>
indexes = pageSize * (fpz",[
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i; -+"#G?g
} B[L m}B[
}else{ 6nTM~]5.
this.totalCount = 0; WJq>%<#
} c9+G
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} j*>J1M3E
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publicint[] getIndexes(){ u=0O3-\h
return indexes; {JfQQP&FV
} z>PVv)X
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publicvoid setIndexes(int[] indexes){ ,'
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this.indexes = indexes; c~hH
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} M|blg!j;
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publicint getStartIndex(){ v_XN).f;
return startIndex; kk78*s {6
} .HZ d.*
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publicvoid setStartIndex(int startIndex){ V&f*+!!2
if(totalCount <= 0) .\caRb[
this.startIndex = 0; ]nsjYsT
elseif(startIndex >= totalCount) D_lRYLA+
this.startIndex = indexes dWd%>9}
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[indexes.length - 1]; rMwa6ZO'm;
elseif(startIndex < 0) jf3Zy:*K
this.startIndex = 0; n=!T(Hk
else{ 4K^cj2X
this.startIndex = indexes 4o#]hB';ni
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[startIndex / pageSize]; *duG/?>P
} v*.R<-X:
} )=f}vHg$
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publicint getNextIndex(){ jq
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int nextIndex = getStartIndex() + hJM&rM7
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pageSize; IRbyW?/Xv
if(nextIndex >= totalCount) GDLi?3q
return getStartIndex(); ^(JrOh'
else `%Fp'`ZM$8
return nextIndex; OG}890$n
} x;[ . ZzQ
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publicint getPreviousIndex(){ ]+:yfDtZd
int previousIndex = getStartIndex() - 4.,EKw3
:-{"9cgFR
pageSize; CmB_g?K
if(previousIndex < 0) +Q+O$-a<
return0; 8;gi8Y
else [r`KoHwdm
return previousIndex; [WDzaRzd
} =%|`gZ
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} a*(Zb|g
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抽象业务类 M@TG7M7Os
java代码: d~8U1}dP
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/** ~m=GS[=
* Created on 2005-7-12 I<QUvs%e
*/ v:SHaUS
package com.javaeye.common.business; cx:_5GF
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import java.io.Serializable; XKGiw 2
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import java.util.List; {v*4mT
[<=RsD_q~
import org.hibernate.Criteria; :=Zd)i)3
import org.hibernate.HibernateException; .
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import org.hibernate.Session; o'lG9ePM|
import org.hibernate.criterion.DetachedCriteria; `p\%ha!,w
import org.hibernate.criterion.Projections; /D"T\KNWr
import $tu
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org.springframework.orm.hibernate3.HibernateCallback; )#AYb
import ; Pk"mC
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org.springframework.orm.hibernate3.support.HibernateDaoS n@`3O'S
'`upSJ;e
upport; <l1/lm<#
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import com.javaeye.common.util.PaginationSupport; +(Y\w^@%H
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public abstract class AbstractManager extends .Vt|;P}
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HibernateDaoSupport { 1le9YL1_g
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privateboolean cacheQueries = false; |Kd6.Mx
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privateString queryCacheRegion; D&m1yl@\J
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publicvoid setCacheQueries(boolean "dCIg{j
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cacheQueries){ Wqv7
this.cacheQueries = cacheQueries; t'F$/mx.
} q<\r}1Dm
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publicvoid setQueryCacheRegion(String |!K&h(J|
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queryCacheRegion){ xd3mAf
this.queryCacheRegion = IG0_
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queryCacheRegion; X)SUFhP\
} pW ~;B*hF
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publicvoid save(finalObject entity){ Oi?Q^ISxP
getHibernateTemplate().save(entity); 3R/6/+S-
} ;7Qe m&
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publicvoid persist(finalObject entity){ @dQr^'h
getHibernateTemplate().save(entity); Yy
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} "a(R>PV%
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publicvoid update(finalObject entity){ g{DOQA
getHibernateTemplate().update(entity); T2-x 1Sw_
} 6iQqOAG
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publicvoid delete(finalObject entity){ h`fZ8|yw
getHibernateTemplate().delete(entity); "Io-%Su+
} 3Dc^lfn
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publicObject load(finalClass entity, ip'v<%,Q3"
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finalSerializable id){ J>dj]1I
return getHibernateTemplate().load E2
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(entity, id); 6AD&%v
} VFV8ik)
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publicObject get(finalClass entity, sUF5Yq:9
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finalSerializable id){ y%--/;
return getHibernateTemplate().get @lB1t=
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(entity, id); A f?&VD4K
} h<m>S,@g
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publicList findAll(finalClass entity){ 9F,XjPK=
return getHibernateTemplate().find("from Ql7opl,
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" + entity.getName()); ;$a|4_U$m
} l$BKE{rg
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publicList findByNamedQuery(finalString 6:r1^q6A9L
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namedQuery){ ICo Z<;p
return getHibernateTemplate FlS)m`
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().findByNamedQuery(namedQuery); Rpcnpo
} 2b
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publicList findByNamedQuery(finalString query, \l6mXIn=>
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finalObject parameter){ ^1}ffE(3>
return getHibernateTemplate +&AU&2As
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().findByNamedQuery(query, parameter); bv[*jr;45
} ,v| vgt
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publicList findByNamedQuery(finalString query, fv3)#>Dgp>
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finalObject[] parameters){ e ]>{?Z
return getHibernateTemplate 8/34{2048
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().findByNamedQuery(query, parameters); gp'n'K]
} gvZLW!={
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publicList find(finalString query){ /|e"0;{
return getHibernateTemplate().find ;LT#/t)}<
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(query); 9]8M {L
} WY~}sE
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publicList find(finalString query, finalObject 7L:R&W6
qf]OSd
parameter){ `|JQ)!Agx
return getHibernateTemplate().find Y@%6*uTLa
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(query, parameter); Df/f&;`
} Q^V`%+
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public PaginationSupport findPageByCriteria w_J`29uc
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(final DetachedCriteria detachedCriteria){ 4sK|l|W
return findPageByCriteria NU/~E"^I.
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); nBiA=+'v
} s.dn~|a
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public PaginationSupport findPageByCriteria ?t.?f`(|
Hp> J,m(*
(final DetachedCriteria detachedCriteria, finalint L{CHAVkV
zck |jhJ6
startIndex){ f<'&_*7,|t
return findPageByCriteria N<Q}4%^c
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(detachedCriteria, PaginationSupport.PAGESIZE, VF==F_l
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startIndex); XWy
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} v:T` D
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public PaginationSupport findPageByCriteria B&Ci*#e
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(final DetachedCriteria detachedCriteria, finalint z06pX$Q.<
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pageSize, " Gn; Q-@
finalint startIndex){ C X'E+
return(PaginationSupport) 't_=%^q
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getHibernateTemplate().execute(new HibernateCallback(){ $BBfsaJPT
publicObject doInHibernate /s*>V@Q
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(Session session)throws HibernateException { G7/LY TT)
Criteria criteria = Z/RUrYeb
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detachedCriteria.getExecutableCriteria(session); Iq}h}Wd
int totalCount = |~CnELF)
ng<`2XgU
((Integer) criteria.setProjection(Projections.rowCount tw3d>H`
'IW+"o
()).uniqueResult()).intValue(); kWz%v
criteria.setProjection =<_5gR
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(null); Yh%wf3
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List items = Tk2kis(n
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criteria.setFirstResult(startIndex).setMaxResults h'fD3Gr&
Sf'5/9<DW+
(pageSize).list(); w+$gY?%
PaginationSupport ps = q(p0#Mk,E
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new PaginationSupport(items, totalCount, pageSize, tr/dd&(Y1
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startIndex); aC$g(>xFt
return ps; B+DRe 8
} \j;uN#)28
}, true); cnPXvD^kY
} (MIw$)#^
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public List findAllByCriteria(final 5)oIPHXw
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DetachedCriteria detachedCriteria){ "=n8PNV/
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return(List) getHibernateTemplate ;Gs**BB&
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().execute(new HibernateCallback(){ _~(Xd@c(
publicObject doInHibernate :{
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(Session session)throws HibernateException { .-Lqo=o\
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); 1;gSf.naG
return criteria.list(); !Cy2>6v7
} r=Q5=(hn
}, true); _Usg`ax-
}
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public int getCountByCriteria(final ?^vZ{B)&0E
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DetachedCriteria detachedCriteria){ yrs3`/
Integer count = (Integer) U[D<%7f
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getHibernateTemplate().execute(new HibernateCallback(){ ggTjd"|)
publicObject doInHibernate =|%T E
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(Session session)throws HibernateException { qU
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Criteria criteria = ui{_w @o
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detachedCriteria.getExecutableCriteria(session); y4L9Cxvs
return Madaxx
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criteria.setProjection(Projections.rowCount A,e^bM
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()).uniqueResult();
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} E}=,"i
}, true); %$xFnGb
return count.intValue(); NLGr=*dq
} ^e,RM_.
} yMkd|1
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用户在web层构造查询条件detachedCriteria,和可选的 -JENY|6
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <Y2!c,"
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PaginationSupport的实例ps。 ] O>7x
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ps.getItems()得到已分页好的结果集 uCfp+
ps.getIndexes()得到分页索引的数组 sK?-@
ps.getTotalCount()得到总结果数 j2M(W/_
ps.getStartIndex()当前分页索引 rtx]dc1m
ps.getNextIndex()下一页索引 Ohag%<1#
ps.getPreviousIndex()上一页索引 #Vigu,zY
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~(/HgFLLu
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做
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一下代码重构了。 zpqNmxmF
# :w2Hf6Q
我把原本我的做法也提供出来供大家讨论吧: PZJ
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首先,为了实现分页查询,我封装了一个Page类: mm-UQ\h
java代码: ]/Qy1,
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/*Created on 2005-4-14*/ /$,=>
package org.flyware.util.page; Z<<gz[$+p
f {Z%:H
/** ja- ~`
* @author Joa i%4k5[f.:
* -z$2pXT ^
*/ HbfB[%
publicclass Page { a
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S{T d/1}
/** imply if the page has previous page */ =Fy8rTdk6r
privateboolean hasPrePage; 8I0Tu
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/** imply if the page has next page */ %H@76NvEz
privateboolean hasNextPage; E2H<{Q
WcO,4:
/** the number of every page */ _j\=FJz[
privateint everyPage; bXwoJ2
]NV ]@*`tO
/** the total page number */ zf>^2t*\
privateint totalPage; xevP2pYG:
5qkuKF
/** the number of current page */ lV6[d8P
privateint currentPage; 0uO=wOIhH
6oh@$.ThG
/** the begin index of the records by the current m<"fRT!Y
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query */ !LOors za
privateint beginIndex; g^ $11
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/** The default constructor */ q,+kPhHEgy
public Page(){ ~!:S p_y
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} <-B"|u
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/** construct the page by everyPage |EV\a[
* @param everyPage !FO^:V<|5
* */ "=\_++
public Page(int everyPage){ 6eYf2sZ;J
this.everyPage = everyPage; =l2Dm
}
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/** The whole constructor */ oA;Ty7s
public Page(boolean hasPrePage, boolean hasNextPage, ^h6$>n5
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int everyPage, int totalPage, +i@yZfT
int currentPage, int beginIndex){ 5Sjr6l3Vq8
this.hasPrePage = hasPrePage; sC5uA
.?>9
this.hasNextPage = hasNextPage; !H|82:`t+
this.everyPage = everyPage; Ryba[Fz4Di
this.totalPage = totalPage; 3E!<p
this.currentPage = currentPage; "R2t&X[9
this.beginIndex = beginIndex; DxKfWb5 R
} w-H%B`/
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/** C7 ]DJn
* @return d9-mWz(V+
* Returns the beginIndex. "vOfAo]`
*/ `,Y[ Z
publicint getBeginIndex(){ 0YpiHoM
return beginIndex; 2@R8P~^W
} fQW_YQsb
IFrb}yH
/** GtM(
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* @param beginIndex H/Ec^Lc+_
* The beginIndex to set. Bq~hV;9nf
*/ e@:P2(WWl
publicvoid setBeginIndex(int beginIndex){ ?l,
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this.beginIndex = beginIndex; qH
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} 0i*'N ch#i
w~$c= JO#
/** S@}B:}2
* @return rI<nUy P?
* Returns the currentPage. c/=y*2,zo
*/ Y0PGT5].@'
publicint getCurrentPage(){ 9jMC|oE
return currentPage;
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} LGo2^Xx
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/** k~1j/VHv
* @param currentPage oT|P1t.
* The currentPage to set. j(%gMVu
*/ 'z-;* !A}j
publicvoid setCurrentPage(int currentPage){ lP@)
this.currentPage = currentPage; (~ ]g,*+
} 5"kx}f2$
pG!(6V-x<E
/** nrTv=*tDj
* @return 9P7xoXJ@y
* Returns the everyPage. "B9[cDM&
*/ &N"'7bK6n
publicint getEveryPage(){ 5>ADw3z'
return everyPage; 0Oc}rRH(C
} >lraYMc<rZ
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/** *U;4t/(
* @param everyPage X`fhln9N
* The everyPage to set. 5@ bc(H
*/ [;?"R-V"z
publicvoid setEveryPage(int everyPage){ JFG",09]
this.everyPage = everyPage; qukjS#>+
} &0+x2e)7g
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/** QGH
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* @return - yC:?
* Returns the hasNextPage. 3tT|9Tb@
*/ ?{
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publicboolean getHasNextPage(){ TsaW5ho<p
return hasNextPage; g> ~cs_N@
} (VYR!(17
3:[!t%Yb
/** =PNdP
* @param hasNextPage Yzj%{fkh
* The hasNextPage to set. ,8c
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*/ =5y`(0 I`U
publicvoid setHasNextPage(boolean hasNextPage){ B*?ZE4`
this.hasNextPage = hasNextPage; Hva2j<h
} &l.x:eD
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/** (O8,zqP9l
* @return L!;^#g
* Returns the hasPrePage. 6P;o 6s
*/ M!N`
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publicboolean getHasPrePage(){ 4 ,p#:!
return hasPrePage; eM?rc55|
} ta&Q4v&-
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/** &sm
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* @param hasPrePage 7$(_j<o`
* The hasPrePage to set. 'FShNY5
*/ t|;%DA)fjw
publicvoid setHasPrePage(boolean hasPrePage){ j\2]M
this.hasPrePage = hasPrePage; ?^LG
hdR
} YF}9k
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/** wL'oImE
* @return Returns the totalPage. $brKl8P
* 9v~1We;{$
*/ Bj@x$v#/^
publicint getTotalPage(){ <fNGhmL
return totalPage; r_Lu~y|
} luW
<V>
h ZoC _\
/** (E!%v`_0
* @param totalPage |/@0~O(6
* The totalPage to set. A)8rk_92Q
*/ qE>i,|rP`
publicvoid setTotalPage(int totalPage){ {bN Y
this.totalPage = totalPage; 6 -]>]Hr-
} za,6du6
;K3d' U
} }%eDEM
&oA~
Tx
k_]\(myq
7egq4gN]2Y
lZ}P{d'f.
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 F(deu^s%{
,#
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个PageUtil,负责对Page对象进行构造: $zdd=.!KiK
java代码: T`uDlo
X$/E>I
SijtTY#r
/*Created on 2005-4-14*/ dIma{uv
package org.flyware.util.page; /x$}D=(CZ
y'^F,WTM
import org.apache.commons.logging.Log; neF8V"-u&
import org.apache.commons.logging.LogFactory; LyIKP$t
-:MmSeG7gO
/** $u:<x
* @author Joa O47PkP8
* jQ6Xr&}
*/ >wA+[81[
publicclass PageUtil { vruD U#
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"5Cf
privatestaticfinal Log logger = LogFactory.getLog Kk 7GZ
R6 ;jY/*#
(PageUtil.class); \fTTkpM
fTBVvY4(
/** bV_j`:MD
* Use the origin page to create a new page i&JpM]N
* @param page +vf:z?I8
* @param totalRecords YUCC*t
* @return <P-$RX
*/ Q |%-9^
publicstatic Page createPage(Page page, int C ck#Y
Y.7}
totalRecords){ MZ WmlJ
return createPage(page.getEveryPage(), Y,'%7u
E${J
page.getCurrentPage(), totalRecords); 6.[)`iF+#
} ?H`j>]%&
=LOk13l\"
/** vHS2q
>
* the basic page utils not including exception .@@an;C
#G[t X6gU
handler ^+wk
* @param everyPage 40u7fojg2
* @param currentPage !~)90Z!
* @param totalRecords u\f3qc,]F
* @return page B_hPcmB
*/ mg` j[<wp
publicstatic Page createPage(int everyPage, int T<P0T<
Ls1B\Aw _
currentPage, int totalRecords){ b:1 L@8s;
everyPage = getEveryPage(everyPage); L/yaVU{aEb
currentPage = getCurrentPage(currentPage); Hs$'0:
int beginIndex = getBeginIndex(everyPage, ~q 7;8<U
q4/909x=
currentPage); UA0F):
int totalPage = getTotalPage(everyPage, `;$h'eI9
o5SQ1;`
totalRecords); =G4u#t)
boolean hasNextPage = hasNextPage(currentPage, 9Sz7\W0
*}w+68eO
totalPage); GWdSSr>
boolean hasPrePage = hasPrePage(currentPage); q*bt4,D&Es
&qKigkLd
returnnew Page(hasPrePage, hasNextPage, RU|X*3";T
everyPage, totalPage, i'=2Y9S}
currentPage, O[FZq47
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beginIndex); b# u8\H
} f!x[ln<
m'bi\1Q
privatestaticint getEveryPage(int everyPage){ /OG zt
return everyPage == 0 ? 10 : everyPage; R&*@@F-dx
} {n&Uf{
k3>YBf`fC
privatestaticint getCurrentPage(int currentPage){ W:vr@e6
return currentPage == 0 ? 1 : currentPage; FY4 T(4#
} y^R4I_* z
ezUQ>
e
privatestaticint getBeginIndex(int everyPage, int RYy,wVh}
pawl|Z'Ez
currentPage){ aClA{
return(currentPage - 1) * everyPage; g*J@[y;
} ~x#vZ=]8
N}x9N.
privatestaticint getTotalPage(int everyPage, int Xb,T{.3@
)M:)y
totalRecords){ ;&S;%W>|
int totalPage = 0; 9->q| E4
y`So&:1
if(totalRecords % everyPage == 0) m*Cu-6&qd
totalPage = totalRecords / everyPage; -ihiG_f
else .T8K-<R
totalPage = totalRecords / everyPage + 1 ; N=~~EtX
J+ts
return totalPage; TH:W#Ot
} 59lj7
sJU`u'w
privatestaticboolean hasPrePage(int currentPage){ Ee)xnY%(
return currentPage == 1 ? false : true; gCJIIzl%Bh
} hqDqt"dKz
9:8|)a(1
privatestaticboolean hasNextPage(int currentPage, EI1?
GB)b
o\!qcoE2W
int totalPage){ #]Y*0Wzpfn
return currentPage == totalPage || totalPage == T$P-<s
5JSrrpGr
0 ? false : true; x)oRSsv!Tr
} :FHA]oec1
Ej"u1F14J
PVYyE3`UB
} WD.U"YI8y
`q_<Im%I
!Z|($21W
qINTCm j
izuF !9
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。 /{*$JF
Qihdn66
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 Vte EDL/w
#{PmNx%M
做法如下: ppN} k)m
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 KY.ZT2k
76@qHTh}
的信息,和一个结果集List: H=~9CJ+tc
java代码: (MLhaux-
+@:L|uFU
OfZN|S+~W
/*Created on 2005-6-13*/ -6C +LbV
package com.adt.bo; r,NgG!zq<
6N" l{!
import java.util.List; ~x]9SXD%
2*1ft>Uty
import org.flyware.util.page.Page; RUo9eQIPD
1@qgF
/** +B"0{>n}F
* @author Joa ;rR/5d1!
*/ %!|O.xxRR
publicclass Result { E^CiOTN
z]@6fM[
private Page page; Or+p%K}-7
s\3q!A?S3
private List content; &JhX+'U
-t-tn22
/** \?lz&<
* The default constructor 5v
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Oq
*/ fZ{[]dn[
public Result(){ |FNCXlgZ
super(); `JURQ:l)3^
} Nneo{j
r{K;|'d%h
/** (f#b7O-Wn
* The constructor using fields =RsXI&&vh
* g0R[xOS|
* @param page `u_Qa
* @param content i.y)mcB4
*/ l=={pb
public Result(Page page, List content){ 3z8C
this.page = page; `I;F$ `\
this.content = content; K5 KyG
} ,6"l (]0
K$[$4 dX]
/** U[\Vj_?(I
* @return Returns the content. z5 m>H;P
*/ wkb$^mU
publicList getContent(){ J/x2qQ$9
return content; P'$ `'J]j
} 9A$m$
KZ:hKY@q
/** h<l1U'Bn7
* @return Returns the page. %,q.),F
*/ anN#5jt
public Page getPage(){ <48<86TP
return page; \}"m'(\c
} 0C$vS`s&
ccJM>9
/** +OHGn;C
* @param content z\!K<d"Xv
* The content to set. X[3}?,aqL
*/ Ip
*g'
public void setContent(List content){ wdas1
this.content = content; 3HC
} CA s>AXbs
;H0 {CkH
/** ko\):DN
* @param page 5Av=3[kh"%
* The page to set. E-2eOT
*/ Y]g?2N=E
publicvoid setPage(Page page){ G4-z3e,crr
this.page = page; ,xi({{L*
} AC- )BM';
} ]0j9>s2|Z
Z;DCI-Wg
[k%4eO2p "
4=<*Vd`p
jLVl4h&
2. 编写业务逻辑接口,并实现它(UserManager, 2I'~2o
g=8un`]7
UserManagerImpl) !q"cpL'4
java代码: 42C<1@>zO
!cX[-}Q
YTaLjITG
/*Created on 2005-7-15*/ R^&q-M=O[
package com.adt.service; 8Cx^0
1Y j~fb(
import net.sf.hibernate.HibernateException; gE7L L=x
"&+3#D
>
import org.flyware.util.page.Page; 5FeFN)
@'2m$a
import com.adt.bo.Result; +0$/y]k
r%]Qlt~K
/** Jh/ E@}'
* @author Joa X` YwP/D
*/ ]+Ixi o
publicinterface UserManager { \,G#<>S
iw?I
public Result listUser(Page page)throws ssQ BSbx
3R$Z[D-
HibernateException; KW3+luI6
Li{~=S@N*
} )7c b6jCU
_.)eL3OF
)6X.Nfkb^k
-7qIToO.
fz_nsVD
java代码:
ZI>km?w
Q;/a F`
L V{Q,DrP
/*Created on 2005-7-15*/ >]D4Q<TY
package com.adt.service.impl; @* ust>7
e /K#>,
import java.util.List; GIwh@4;
8(U{2B8>\%
import net.sf.hibernate.HibernateException; ;3'NMk
MjL)IgT
import org.flyware.util.page.Page; kSncZ0K{
import org.flyware.util.page.PageUtil; j Ch=@<9
Q4]4@96Aj
import com.adt.bo.Result; kLSrj\6I[
import com.adt.dao.UserDAO; ?)4?V\$
import com.adt.exception.ObjectNotFoundException; y(jg#7)
import com.adt.service.UserManager; ^ZRYRA
W6c]-pc
/** +K",^6%1
* @author Joa /+K?
*/ WN]<q`.
publicclass UserManagerImpl implements UserManager { 'I}:!Z
J4$!
68
private UserDAO userDAO; .^(/n9|o-
+C]&2zc.
/** j{++6<tr
* @param userDAO The userDAO to set. A#wEuX=[
*/ I3b"|%
publicvoid setUserDAO(UserDAO userDAO){ [I*!
lbt
this.userDAO = userDAO; mB'3N;~
} jdA
]2]
v-j3bB
/* (non-Javadoc) OW;tT=ql
* @see com.adt.service.UserManager#listUser $^/0<i$
<i\A_qqc/
(org.flyware.util.page.Page) C@\{ehG
*/ knp>m,w
public Result listUser(Page page)throws cR7wx 0Aj
6=_~0PcY
HibernateException, ObjectNotFoundException { PyC0Q\$%
int totalRecords = userDAO.getUserCount(); (?)7)5H
if(totalRecords == 0) \;5\9B"i
throw new ObjectNotFoundException }ET,ysa
,~PYt*X4
("userNotExist"); 4<,|*hAT
page = PageUtil.createPage(page, totalRecords); ;F:fM!l=
List users = userDAO.getUserByPage(page); }=](p-] 5
returnnew Result(page, users); 5f'DoT
} alMYk
l~s7Ae
} lJ;J~>
EV M7Q>
NcS.49
;Y9=!.Ak0y
ff?t[GS
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Rg&-0b
)}v3q6?_
询,接下来编写UserDAO的代码: R9vT[{!i
3. UserDAO 和 UserDAOImpl: $"JpFT
java代码: NR%Y+8^M
,Z9>h[JF
iOw3MfO
/*Created on 2005-7-15*/ gbBy/_b
package com.adt.dao; W[bmzvJ_X
;E;To\NCYF
import java.util.List; E`\8TqO
C2U~=q>>
import org.flyware.util.page.Page; rt-\g1x
0Wvq>R.(]7
import net.sf.hibernate.HibernateException; nv0@xnbz
q(o/yx{bm
/** F4#g?R::U
* @author Joa YB))S!;Ok
*/ ^WYQ]@rh3
publicinterface UserDAO extends BaseDAO { QWnndI_4p
R@Y=o].2
publicList getUserByName(String name)throws 'Ye v}QM
FwAKP>6 *
HibernateException; @~
Dh'w2q
c~,23wP1
publicint getUserCount()throws HibernateException; ]DG?R68DQ
>QE{O.Z
publicList getUserByPage(Page page)throws ^ZeJ[t&!#
|[xi/Q^7
HibernateException; BG`s6aC|z<
D>L2o88
} K<sC F[
WKM)*@#,
j`*N,*ha
r{Rg920
$P
o}
java代码: $o?@0
eJ8]g49mD6
~,6b_W p/
/*Created on 2005-7-15*/ 5AeQQU
package com.adt.dao.impl; sd re#@n}
OKOu`Hz@
import java.util.List; yoe}$f4
imL_lw^?
import org.flyware.util.page.Page; _W!p8cB
b4 #R!
import net.sf.hibernate.HibernateException; f&@BKx
import net.sf.hibernate.Query; G\gMC
<3
/?-7Fg+,
import com.adt.dao.UserDAO; qOV[TP,
CG]Sj*SA~
/** :,pSWfK H
* @author Joa 9W`Frx'h1
*/ NmIHYN3
public class UserDAOImpl extends BaseDAOHibernateImpl B6P|Z%E;D6
9.O8/0w7LV
implements UserDAO { k,Qskd-N]
:c[n\)U[aa
/* (non-Javadoc) uwIc963
* @see com.adt.dao.UserDAO#getUserByName R>@uY(>dJ
Vn=qV3OE]
(java.lang.String) KLQTKMNv
*/ pI[ZBoR~
publicList getUserByName(String name)throws \kamcA
)U<Y0bZA!
HibernateException { T5Eseesp
String querySentence = "FROM user in class iX{G]< n
1t[j"CG(o
com.adt.po.User WHERE user.name=:name"; ~:Uwg+]j
Query query = getSession().createQuery hPhZUL%
6&U+6gb
(querySentence); K!AAGj`
query.setParameter("name", name); W1aa:hEf
return query.list(); qf)$$ qi
} vC;]jJb:
'BMy8
/* (non-Javadoc) %WFu<^jm
* @see com.adt.dao.UserDAO#getUserCount() S*)1|~pRvQ
*/ n}-3o]ku
publicint getUserCount()throws HibernateException { Ok-.}q>\Mv
int count = 0; ;(6g\'m
String querySentence = "SELECT count(*) FROM Rs& @4_D
xgsjm))
user in class com.adt.po.User"; "$HbK
@]!h
Query query = getSession().createQuery [f~N_G6I^o
o/cjXun*
(querySentence); ^,Ydr~|T
count = ((Integer)query.iterate().next M.}7pJ7f
#b0{#^S:
()).intValue(); _1Z=q.sC
return count; lt'I,Xt
} Eu<1Bse;
Mq%,lJA\
/* (non-Javadoc) 7YWNd^FI
V
* @see com.adt.dao.UserDAO#getUserByPage HHk)ZfWRo
Y]aW)u
(org.flyware.util.page.Page) `:{B(+6
*/ ?|;yVew
publicList getUserByPage(Page page)throws 5-u=o)>
u<ySd?
HibernateException { eHg3}b2r
String querySentence = "FROM user in class "](6lB1Oe
7XrfuG*L$
com.adt.po.User"; cvsz%:Vs
Query query = getSession().createQuery z+2V4s =
wgeNs9L
(querySentence); pj|pcv^
query.setFirstResult(page.getBeginIndex()) Q'B6^%:<~
.setMaxResults(page.getEveryPage()); ?@6b>='!
return query.list(); q(^Q3
} 7[v%GoE
H/F+X?t$0
} }peBR80tQ
[BbutGvj
1MkI0OZE
XhU@W}}
T".]m7!
至此,一个完整的分页程序完成。前台的只需要调用 Mc sTe|X
-7>)i
userManager.listUser(page)即可得到一个Page对象和结果集对象 ("7M
b{
*mG`_9
的综合体,而传入的参数page对象则可以由前台传入,如果用 Z5G!ct:W
kQdt}o])
webwork,甚至可以直接在配置文件中指定。 wz8PtfZ
}$su4A@0
下面给出一个webwork调用示例: OV CR0
java代码: 3cl9wWlJ_E
1pp -=$k
WUdKLx%F
/*Created on 2005-6-17*/ e=P
package com.adt.action.user; JYqSL)Ta*t
nCg66-3A
import java.util.List; cRvvzX
2R-A@UE2
import org.apache.commons.logging.Log; $.6K!x{(
import org.apache.commons.logging.LogFactory; i hL/n
import org.flyware.util.page.Page;
05\dl
>gtQw!
import com.adt.bo.Result; >v;8~pgO
import com.adt.service.UserService; :y]Omp
import com.opensymphony.xwork.Action; \@a$'
Rxpn~QQ
/** K2_Qu't0$
* @author Joa Weoj|0|t
*/ VUU]Pu &
publicclass ListUser implementsAction{ \79X{mcd
*2"6fX[
privatestaticfinal Log logger = LogFactory.getLog rk2xKm^w
PrF}a<:n:
(ListUser.class); D?jk$^p~m#
s)A<=)w/e
private UserService userService; %u{W7
JD>d\z2QC
private Page page; [ Mg8/Oy
2pHR_mrb
privateList users; ,n,RFa
I 1d0iU
/* yKagT$-
* (non-Javadoc) =?0lA_
0
* $L4/I !Yf
* @see com.opensymphony.xwork.Action#execute() 5vzceQE}
*/ E&$_`m;
publicString execute()throwsException{ v'2[[u{7*
Result result = userService.listUser(page); 4\t1mocCSN
page = result.getPage(); W~T}@T:EN
users = result.getContent(); #PvB/3
return SUCCESS; Q3W#`6jpF
} aAvsb$
4wzlJ19E(
/** Qq-"Cg@-/
* @return Returns the page. SD\=
m/W
*/ /{2*WI;
public Page getPage(){ t5k!W7C
return page; bte~c
} {'+QH)w(
}0hL~i
/** FX<b:#
* @return Returns the users. }!#gu3
*/ |iFVh$N
publicList getUsers(){ <3PL@orO
return users; Q\
^[!|
} UCrh/b Tm
3CjL\pIC
/** FUK3)lT
* @param page WnFG{S{s
* The page to set. NIr@R7MKd
*/ k`HP"H
publicvoid setPage(Page page){ bSwWszd~
this.page = page; ({0)@+V8
} v<\A%
[mxTa\
/** $5`!Z%>/
* @param users a\uie$"cr]
* The users to set. /T^ JS
*/ F,Xo|jjj
publicvoid setUsers(List users){ gQSNU_o Z
this.users = users; z7.|fE)<6
} xynw8;Y,
0XwHP{XaO
/** :A46~UA!$
* @param userService E{xVc;t
* The userService to set. XALI<ZY
*/ *MNHT`Y^o
publicvoid setUserService(UserService userService){ =!Vf
this.userService = userService; g o5]<4`r
} d&cU*
} SQsSa1
QlFZO4 P3|
+YOKA*
y<R=
PeX1wK%f
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, &MR/6"/s
z9
u$~
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 D;GD<zC]
#yseiVm;
么只需要: (LvS
:?T}
java代码: $ZPX]2D4B#
m4k
Bj*6c{
Sydh2d
<?xml version="1.0"?> &Wp8u#4L
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork S,fCV~Cio?
P27%xV-n>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- T[k4lM
C;AA/4Ib
1.0.dtd"> Yw3oJf&
|9xI_(+{kP
<xwork>
r#PMy$7L
_eSdnHWx
<package name="user" extends="webwork- 80}+MWdo
js^ ,(CS
interceptors"> 'PZ|:9FX!
[@<sFP;g
<!-- The default interceptor stack name >$67 7
>t,M
--> Gz
I~TWc+G
<default-interceptor-ref vq*Q.0 M+
VO3pm6r5
name="myDefaultWebStack"/> kEeo5XN
e;bYaM4UX
<action name="listUser" Mpue
;?fS(Vz~
class="com.adt.action.user.ListUser"> .@)mxC:\K9
<param lA!"z~03*
}/dRU${!
name="page.everyPage">10</param> ubsSa}$q
<result #BVtL :x@
tary6K9K+
name="success">/user/user_list.jsp</result> ,y`CRlr:
</action> )O+}T5c=
lv0nEj8F
</package> -F&U
HysS_/t~
</xwork> Z#d&|5Xj
?rVy2!
\mM<\-'p
|rw%FM{F
N(6|yZ<J3M
0X8t>#uF
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Eh</? Qv\
z@|dzvjl
Q
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 'z@ 0
ha@L94Lq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 @tohNO>
"|Fy+'5}
mpC`Yk
Ok5<TZ6t4k
@4d)R
我写的一个用于分页的类,用了泛型了,hoho WS-dS6Q}
0|xIBg)
java代码: p?[Tm*r
gwrYLZNGI
p;)"
package com.intokr.util; %)jxW{
e"]8T},
import java.util.List; W/z7"#
x_=n-lAF
/** WtQ8X|\`
* 用于分页的类<br> 4EI7W,y
* 可以用于传递查询的结果也可以用于传送查询的参数<br> %R#L
* _cTh#t ^
* @version 0.01 :Eh\NOc_O
* @author cheng HjvCujJ
*/ 0C<[9Dl.G8
public class Paginator<E> { >FjR9B
privateint count = 0; // 总记录数 7qO a
;^T
privateint p = 1; // 页编号 t-
u VZ!`\
privateint num = 20; // 每页的记录数 (2ur5uk+
privateList<E> results = null; // 结果 >4Y3]6N0.F
rD?L
/** uJx"W
* 结果总数 yNW\?Z$@q
*/ uY_SU-v
publicint getCount(){ %98' @$:0
return count; &wd;EGGT!q
} 0tISXu-
d\MLOXnLq;
publicvoid setCount(int count){
N#V.1<Y
this.count = count; m^' uipa\
} lN,/3\B
H|ozDA
/** rrg96WD
* 本结果所在的页码,从1开始 U<"WK"SM
* OJT1d-5p
* @return Returns the pageNo. U~{du;\
*/ )m6M9eC
publicint getP(){ HS'Vi9
return p; 4p;aS$Q
} 4%WzIzRb
_(J&aY\
/** g&dPd7
* if(p<=0) p=1 IcP)FB4
* 4=uhh
* @param p 64Lx-avf
*/ R [H+qr
publicvoid setP(int p){ Yw _+`,W
if(p <= 0) 0![
+Q4"
p = 1; a{!QOX%K
this.p = p; 8u[-'pV!
} i'stw6*J
,F&g5'
/** tg^sCxz9]
* 每页记录数量 RMO,ZVq
*/ V)Z70J<'
publicint getNum(){ U$oduY#
return num; \
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} %B.D^]S1:
nEzf.[+9/
/** mw_Ew]&
* if(num<1) num=1 *5bLe'^\|K
*/ Y_`- 9'&
publicvoid setNum(int num){ <Q|d&vDVfV
if(num < 1) 5J8r8` t
num = 1; '`'GK&)
this.num = num; }QZQ3@
} G!4(BGx&
zf3v5Hk
/** yH][(o=2
* 获得总页数 AM=z`0so
*/ kq\)MQ"/X
publicint getPageNum(){ .CP&bJP%
return(count - 1) / num + 1; s
{^yj
} +_-bJo2a
:akT 'q#
/** No2b"G@
* 获得本页的开始编号,为 (p-1)*num+1 t|t#vcB
*/ CJ}5T]WZ
publicint getStart(){ @FdSFQ/9
return(p - 1) * num + 1; ,C3,TkA]
} }kg ye2[
u!1{Vt87
/** M$f7sx
* @return Returns the results. O25lLNmO
*/ 8* Jw0mSw
publicList<E> getResults(){ 8H[:>;SI
return results; S/;bU:
} R_=6GZH$G
zB yqD$
public void setResults(List<E> results){ -i-? .:
this.results = results; Z{'i F
} tTd\|
|bgo;J/
public String toString(){ bLt.O(T}
StringBuilder buff = new StringBuilder #^+DL]*l
(sWLhUgRX
(); E*i#?u
buff.append("{"); \"hJCP?,
buff.append("count:").append(count); e<r,&U$
buff.append(",p:").append(p); e%W$*f
buff.append(",nump:").append(num); QeF3qXI
buff.append(",results:").append vloF::1
ftH:r_"O#
(results); U*.0XNKp{
buff.append("}"); @JdZ5Q
return buff.toString(); a22XDes=
} e}1uz3Rh
:6$>_m=i
} V)}rEX
-W>'^1cR
(XoH,K?{z