Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 14!J\`rI
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 bFezTl{M
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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 A=UIN!
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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 0@lC5-=
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分页支持类: q-%KfZ@(|
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java代码: Xp6*Y1Y
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package com.javaeye.common.util; [IFRwQ^%_O
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import java.util.List; jHH
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publicclass PaginationSupport { WG
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rs Uw(K^
publicfinalstaticint PAGESIZE = 30; @z)tC@
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privateint pageSize = PAGESIZE; ^YJA\d@
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privateList items; :ZS8Zm"
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privateint totalCount; 6^O?p2xpo
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privateint[] indexes = newint[0]; 1L8ULxi_?]
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privateint startIndex = 0; |8 2tw|<o
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public PaginationSupport(List items, int jne9=Als5
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totalCount){ ^>8]3@ Nh
setPageSize(PAGESIZE); &17,]# 3
setTotalCount(totalCount); t"/"Ge#a
setItems(items); WG/J4H`Od
setStartIndex(0); 5A$az03y$\
} $;uWj|
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public PaginationSupport(List items, int KHecc/,,S
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totalCount, int startIndex){ LQ\
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setPageSize(PAGESIZE); VnSj:LUD
setTotalCount(totalCount); 4Sstg57x~
setItems(items); 8o7]XZE=)
setStartIndex(startIndex); -*hb^MvP
} R``VQ
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public PaginationSupport(List items, int ]~00=nXFM/
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totalCount, int pageSize, int startIndex){ _Sgk^i3v
setPageSize(pageSize); Uc_`Eh3y
setTotalCount(totalCount); Fy@#r+PgWp
setItems(items); nj^q@h
setStartIndex(startIndex); %Mng8r
} *76viqY;dE
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publicList getItems(){ ?3,64[
return items; Dg>'5`&
} 4ZJT[zi
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publicvoid setItems(List items){ >}DjHLTW\
this.items = items; ~"q,<t
} 37O#aJ,K
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publicint getPageSize(){ {8#N7(%z
return pageSize; `+hy#1]
} Md>f
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publicvoid setPageSize(int pageSize){ ra%R:xX
this.pageSize = pageSize; w
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} < [S1_2b.t
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publicint getTotalCount(){ oBj>9I;
return totalCount; NB+$ym
} 5G'&9{oB
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publicvoid setTotalCount(int totalCount){ YR|(;B
if(totalCount > 0){ =WmBpUh
this.totalCount = totalCount; zh^jWu
int count = totalCount / #'4<> G]
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pageSize; "zedbJ0
if(totalCount % pageSize > 0) -.b
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count++; nI*(a:
indexes = newint[count]; t ?9;cS4
for(int i = 0; i < count; i++){ i_0,BVC
indexes = pageSize * WAwfL?
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} 7"n)/;la
}else{ 6)#- 5m
this.totalCount = 0; rKzv8d
} ayH%
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} !$p2z_n$@.
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publicint[] getIndexes(){ wWJQ~i?
return indexes; %Rd~|$@>x
} ]{AOh2Z.hv
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publicvoid setIndexes(int[] indexes){ JA?,0S
this.indexes = indexes; a(}VA|l
} + q
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publicint getStartIndex(){ mEB2RLCM
return startIndex; |5O >>a()
} Et}C`vZ+Ve
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publicvoid setStartIndex(int startIndex){ h;EwkbDQg>
if(totalCount <= 0) nE]~E xr
this.startIndex = 0; x2j/8]'o
elseif(startIndex >= totalCount) (o x4K{
this.startIndex = indexes 2vqmsl?
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[indexes.length - 1]; oh7#cFZZ0
elseif(startIndex < 0) nr<WO~Xw~
this.startIndex = 0; hl6,#2$
else{ Y7*(_P3/
this.startIndex = indexes 6(N.T+;]
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[startIndex / pageSize]; #1QX!dK+
} sR"zRn
} `ICcaRIN8I
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publicint getNextIndex(){ r@*=|0(OrK
int nextIndex = getStartIndex() + ,J~,ga~
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pageSize; O+G~Qp0b>
if(nextIndex >= totalCount) WFU?o[k-O
return getStartIndex(); 6keP':bt
else z:Xj_ `p
return nextIndex; N,j>;x3xT
} !lQ#sL`
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publicint getPreviousIndex(){ `e'G.@
int previousIndex = getStartIndex() - .k# N7[q=
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pageSize; 6}VUD
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if(previousIndex < 0) oupJJDpP
return0; =cf{f]N
else awj+#^
return previousIndex; T&9`?QD
} c;c:Ea5
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} D^66p8t
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抽象业务类 u^`eKak"l
java代码: OJMvn'y
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/** ^G}# jg.
* Created on 2005-7-12 Bz~ -2#l
*/ 5a=nF9/
package com.javaeye.common.business; 7*zB*"B'1t
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import java.io.Serializable; jg~_'4f#
import java.util.List; {iA^rv|
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import org.hibernate.Criteria; FJT1i@N
import org.hibernate.HibernateException; ],[)uTZc
import org.hibernate.Session; G52Z)^
import org.hibernate.criterion.DetachedCriteria; ]*;F. pZ
import org.hibernate.criterion.Projections; M3(k'q7&:
import ZXt?[Ll
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org.springframework.orm.hibernate3.HibernateCallback; Uo6(|mm
import {155b0
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org.springframework.orm.hibernate3.support.HibernateDaoS ,J(lJ,c
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upport; +O+<Go@a
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import com.javaeye.common.util.PaginationSupport; })[($$f/
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public abstract class AbstractManager extends p<5!02yQ\
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HibernateDaoSupport { q4ipumy*
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privateboolean cacheQueries = false; ~Ltr.ci
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privateString queryCacheRegion; )~
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publicvoid setCacheQueries(boolean </s,pe79B
)a cV-+{
cacheQueries){ jGD%r~lN
this.cacheQueries = cacheQueries; G{RTH_p
} 6>DLp}d
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publicvoid setQueryCacheRegion(String ssl&5AS
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queryCacheRegion){ V1<`%=%_W
this.queryCacheRegion = HZZDv+
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queryCacheRegion; v01#>,R
} L"vj0@n'0
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publicvoid save(finalObject entity){ iiNSDc
getHibernateTemplate().save(entity); usOx=^?=
} MzTW8
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publicvoid persist(finalObject entity){ j*zD0I]
getHibernateTemplate().save(entity); kMxjS^fr
} -MfQ&U
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publicvoid update(finalObject entity){ '*R%^RK
getHibernateTemplate().update(entity); $1@,Qor
} *H2]H@QHN
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publicvoid delete(finalObject entity){ Z8&'f,
getHibernateTemplate().delete(entity); =+oZtP-+o
} 3&*'6D
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publicObject load(finalClass entity, ngUHkpYS5
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finalSerializable id){ |4C^$
return getHibernateTemplate().load :6Pad
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(entity, id); C1fyV]
} '^}+Fv<O
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publicObject get(finalClass entity, 3!#/k+,C
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finalSerializable id){ !B^K[2`)N
return getHibernateTemplate().get wahZK~,EaY
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(entity, id); ?<~WO?
} /[pqI0sf<A
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publicList findAll(finalClass entity){ I>n
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return getHibernateTemplate().find("from nSS=%,?
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" + entity.getName()); !j^&gRH
} (tCib 4
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publicList findByNamedQuery(finalString @Icq1zb]
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namedQuery){ O\Eqr?%L)
return getHibernateTemplate .eF_cD7v
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().findByNamedQuery(namedQuery); ctn,
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} y4jU{,
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publicList findByNamedQuery(finalString query, <nzN $"%
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finalObject parameter){ {j
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return getHibernateTemplate r>|-2}{N/
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().findByNamedQuery(query, parameter); p2 ! FcFi
} 8Y{s;U0n
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publicList findByNamedQuery(finalString query, A
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finalObject[] parameters){ ]<trA$ 0
return getHibernateTemplate s&tE_
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().findByNamedQuery(query, parameters); >k(MUmhX
} EX
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publicList find(finalString query){ ^[q /Mw
return getHibernateTemplate().find Uems\I0
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(query); Mr3-q
} =/9^,
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publicList find(finalString query, finalObject LN^f1/b*
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parameter){ jna;0)
return getHibernateTemplate().find FN87^.^2S
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(query, parameter); WFv!Pbq,
} Gi?_ujZR
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public PaginationSupport findPageByCriteria v#oi0-9o[
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(final DetachedCriteria detachedCriteria){ q{' ~+Nq
return findPageByCriteria -n))*.V
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); -j`LhS~|
} VLvS$0(}Z
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public PaginationSupport findPageByCriteria A o/vp-e
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(final DetachedCriteria detachedCriteria, finalint 3YL
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startIndex){ AHbZQulC
return findPageByCriteria ;)hw%Z]Jj$
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(detachedCriteria, PaginationSupport.PAGESIZE, F jrINxL7^
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startIndex); X_ TiqV
} CboLH0Fa
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public PaginationSupport findPageByCriteria Y "jE'
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(final DetachedCriteria detachedCriteria, finalint 2HL9E|h
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pageSize, h0 |}TV^UJ
finalint startIndex){ 2KJ1V+g@a6
return(PaginationSupport) DDd/DAkCX
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getHibernateTemplate().execute(new HibernateCallback(){ Z|m`7xeCy
publicObject doInHibernate U.oksD9v
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(Session session)throws HibernateException { yW7'?
Criteria criteria = Kuw^qX"
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detachedCriteria.getExecutableCriteria(session); t%VDRZo7
int totalCount = >t+
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((Integer) criteria.setProjection(Projections.rowCount wxQ>ifi9Z
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()).uniqueResult()).intValue(); Ty4S~ClO#'
criteria.setProjection U>qHn'M
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(null); s4LO&STh{
List items = Rd&9E
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criteria.setFirstResult(startIndex).setMaxResults 7{kP}?
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(pageSize).list(); X"asfA[6K
PaginationSupport ps = - xm{&0e)
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new PaginationSupport(items, totalCount, pageSize, Jl<ns,Zg
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startIndex); #&.]"
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return ps; x34f9!
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} ,?cH"@RJ
}, true); >7Jr^o#|_x
} 0?Q_@Y
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public List findAllByCriteria(final cDEJk?3+
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DetachedCriteria detachedCriteria){ zU5Hb2a
return(List) getHibernateTemplate {d3<W N
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().execute(new HibernateCallback(){ dE`-\J
publicObject doInHibernate m}j:nk
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(Session session)throws HibernateException { G5.nPsuM
Criteria criteria = KP"%Rm`XN
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detachedCriteria.getExecutableCriteria(session); "hz\Z0zg2
return criteria.list(); d'
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} {D&9UZm
}, true); !c#]?b%
} o:q1beU
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public int getCountByCriteria(final s?Uh| BfB
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DetachedCriteria detachedCriteria){ g.JN_t5
Integer count = (Integer) /.Nov
= VLS/\A
getHibernateTemplate().execute(new HibernateCallback(){ k^ F@X
publicObject doInHibernate x]mxD|?f
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(Session session)throws HibernateException { "&Dx=Yf
Criteria criteria = `~UZU@/x
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detachedCriteria.getExecutableCriteria(session); OX:O^ (-r,
return q*![AzFh
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criteria.setProjection(Projections.rowCount ?!w^`D0}o
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()).uniqueResult(); m,3er*t{
} Uu6L~iB
}, true); NIZ<0I*5
return count.intValue(); f#%JSV"7
} PYB+FcR6?n
} `T/~.`R
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用户在web层构造查询条件detachedCriteria,和可选的 ,p{`pma
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 zHB_{(o7
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PaginationSupport的实例ps。 #)+- lPe
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ps.getItems()得到已分页好的结果集 si1*Wt<3Bc
ps.getIndexes()得到分页索引的数组 !2Dy_U=
ps.getTotalCount()得到总结果数
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ps.getStartIndex()当前分页索引 GYRYbiwqdi
ps.getNextIndex()下一页索引 BOlAm*tFt
ps.getPreviousIndex()上一页索引 NX* O_/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =<f-ob8,
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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 TmRxKrRs
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一下代码重构了。 xIbMs4'iEx
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我把原本我的做法也提供出来供大家讨论吧: 8$P>wCK\l
QEJGnl676
首先,为了实现分页查询,我封装了一个Page类: R"xp%:li
java代码: s3t!<9[m
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/*Created on 2005-4-14*/ Hhv$4;&X
package org.flyware.util.page; xfHyC'?
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/** QlzQ]:dWC
* @author Joa g()m/KS<
* b~Z=:'m8
*/ =HE
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publicclass Page { 9N
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/** imply if the page has previous page */ kV)'a
privateboolean hasPrePage; U6{dI@|B
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/** imply if the page has next page */ km>o7V&4G
privateboolean hasNextPage; S<oQ}+4[~
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/** the number of every page */ \iZ1W
privateint everyPage; TETsg5#
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/** the total page number */ -CU,z|g+
privateint totalPage; XI
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/** the number of current page */ IMR$x(g=
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privateint currentPage; *]9XDc]{j1
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/** the begin index of the records by the current fiqj;GW
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query */ =0Y'f](2eW
privateint beginIndex; 0C7" 3l
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/** The default constructor */ |vN$"mp^a
public Page(){ k`Y,KuBpM
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} ;@O(z*14@
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/** construct the page by everyPage rN'k4V"K
* @param everyPage L%4tw5*N
* */ 3?6 Ber y=
public Page(int everyPage){ g&8 .A(
this.everyPage = everyPage; 7dx4~dF
} @@xF#3
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/** The whole constructor */ 2f
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public Page(boolean hasPrePage, boolean hasNextPage, /iTH0@Kw;
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int everyPage, int totalPage, LDSbd,GF
int currentPage, int beginIndex){ OQ
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this.hasPrePage = hasPrePage; <C2c"=b
this.hasNextPage = hasNextPage; uFa-QG^Y{
this.everyPage = everyPage; y& Gw.N}<r
this.totalPage = totalPage; ec,z6v^9
this.currentPage = currentPage; \>_eEZ5
this.beginIndex = beginIndex; `_6@3-%
} o<Ke3?J\
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/** ^O?l9(=/u
* @return il<gjlyR]L
* Returns the beginIndex. NF@i#:
*/ ([E#zrz%
publicint getBeginIndex(){ &7JEb]1C
return beginIndex; LH1BZ(5g
} :^C#-O
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/** ..sJtA8
* @param beginIndex Hd96[Uo
* The beginIndex to set. D]3bwoFo&u
*/ MX%|hIOpr
publicvoid setBeginIndex(int beginIndex){ N2 M?5fF
this.beginIndex = beginIndex; Z{j!s6Y@{
} )2
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/** aA!@;rR<yU
* @return 1ZGQhjcx
* Returns the currentPage. ajg7xF{l)
*/ g#pIMA#/
publicint getCurrentPage(){ B`t)rBy
return currentPage; 'lSnyW{
} $L $j
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/** W`
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* @param currentPage Y,p2eAss
* The currentPage to set. g0[<9.ke
*/ H"kc^G+(R"
publicvoid setCurrentPage(int currentPage){ E0WrpGZ
this.currentPage = currentPage; Ix%"4/z>
} 4C2>0O<^s
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/** ?}!gLp
* @return D~t"9Z\
* Returns the everyPage. T/X?ZK(T
*/ ^Hy)<P
publicint getEveryPage(){ QqT6P`0u
return everyPage; N
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} N69eIdl
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/** v{\n^|=])
* @param everyPage Gff[c%I
* The everyPage to set. .T
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*/ 96([V|5K
publicvoid setEveryPage(int everyPage){ 5r2ctde)Y
this.everyPage = everyPage; UlLM<33_)
} e{#a{`?Uez
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/** : Oz7R:
* @return Oujlm|
* Returns the hasNextPage. 1' @lg*^9
*/ &d &oP
publicboolean getHasNextPage(){ 6#lC(ko'
return hasNextPage; Xk$l-Zfse
} u"
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/** :w&)XI34
* @param hasNextPage %I2xK.8=
* The hasNextPage to set. \p=W4W/
*/ ]I.& .?^i0
publicvoid setHasNextPage(boolean hasNextPage){ e*'|iuDrY
this.hasNextPage = hasNextPage; ofJ]`]~VG
} E]U3O>hf
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/** 7! A%6
* @return Eg-Mm4o
* Returns the hasPrePage. $'mB 8 S
*/ c#4L*$ViF
publicboolean getHasPrePage(){ +e3WwUx
return hasPrePage; %?9r (&
} 35]G_\
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/** =='{[[J
* @param hasPrePage ~m;MM)_V
* The hasPrePage to set. j*Wh;I+h
*/ "!_
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publicvoid setHasPrePage(boolean hasPrePage){ #SLxN AH
this.hasPrePage = hasPrePage; G*wW&R)
} ^*UfCoj9Z
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/** +]~w ?^h
* @return Returns the totalPage. }+RF~~H/
* <[B[
*/ SAxa7B/U2
publicint getTotalPage(){ SAo\H
return totalPage; elHarey`f
} ^@5ui;JV
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/** {'Qk>G
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* @param totalPage AL$Ty
* The totalPage to set. Kac j
*/ P)j9\ muc
publicvoid setTotalPage(int totalPage){ ,m'#>d&zO
this.totalPage = totalPage; m ?"%&|
} Xgth|C}k
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} a:%5.!Vd
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[
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6l]?%0[*
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 D.CsnfJ
2?7hUaHX
个PageUtil,负责对Page对象进行构造: |ij5c@~&
java代码: 1eyyu!
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/*Created on 2005-4-14*/ l
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package org.flyware.util.page; >W]"a3E
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import org.apache.commons.logging.Log; #_L&
import org.apache.commons.logging.LogFactory; Ri6 br
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/** WuZn|j'
* @author Joa $>s@T(
* PL_wa(}y]D
*/ VP[!ji9P
publicclass PageUtil { M~Dc5\T
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privatestaticfinal Log logger = LogFactory.getLog [>9"RzEl
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(PageUtil.class); g
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/** ^X'7>{7Io
* Use the origin page to create a new page MCpK^7]k
* @param page Q>g$)-8
* @param totalRecords `rJ ~*7-
* @return He;%6OG{
*/ PCnJ2
publicstatic Page createPage(Page page, int Guc^gq}
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totalRecords){ >ZsK5v
return createPage(page.getEveryPage(), OWfj<#}t+
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page.getCurrentPage(), totalRecords); <rmV$_
} U.h PC3
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/** .u3W]5M|
* the basic page utils not including exception n:)Y'52}
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handler pra&A2Y\
* @param everyPage SP1oBR"3
* @param currentPage 640V&<+v
* @param totalRecords 6RodnQ
* @return page gq &85([
*/ _Hj,;Z
publicstatic Page createPage(int everyPage, int V7i`vo3Cc
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currentPage, int totalRecords){ :?W:'% (`[
everyPage = getEveryPage(everyPage); - & r{%7
currentPage = getCurrentPage(currentPage); lB@K;E@r8
int beginIndex = getBeginIndex(everyPage, D$
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currentPage); Vk
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int totalPage = getTotalPage(everyPage, 9oz)E>K4f
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totalRecords); JwVv+9hh
boolean hasNextPage = hasNextPage(currentPage, 1D]wW%us
j` lK}
totalPage); nzDY!Y
boolean hasPrePage = hasPrePage(currentPage); Z`MQ+
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returnnew Page(hasPrePage, hasNextPage, Pw.+DA
everyPage, totalPage, 9Ua@-
currentPage, mJT
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beginIndex); /9Xf[<
} &ayoTE^0,
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privatestaticint getEveryPage(int everyPage){ GjBQxn
return everyPage == 0 ? 10 : everyPage; ?OFvGd
} 9hU@VPB~
zZQoY_UI
privatestaticint getCurrentPage(int currentPage){ +^:K#S9U
return currentPage == 0 ? 1 : currentPage; } q(0uzaG
} =Y0m;-1M
{ q<l]jn9
privatestaticint getBeginIndex(int everyPage, int Wd#6Y}:
Fjb[Ev
currentPage){ 5N/;'ySAE_
return(currentPage - 1) * everyPage; ~gD]JiiA
} GS%Dn^l
=|/b[Gd(
privatestaticint getTotalPage(int everyPage, int k@'.d)y0`
duCm+4,.
totalRecords){ nFSa~M
int totalPage = 0; uPPe"$
=%p{"<
if(totalRecords % everyPage == 0) 8:bNFgJD
totalPage = totalRecords / everyPage; H Vy^^$
else .wywO|
totalPage = totalRecords / everyPage + 1 ; {JJ`|*H$_
[(mq8Nb
return totalPage; ?}.(k/
} I$&/?ns@O
#0c`"2t&M
privatestaticboolean hasPrePage(int currentPage){ [B[ J%?NS
return currentPage == 1 ? false : true; =zKp(_[D
} P?F:x=@'|
dGg+[?
privatestaticboolean hasNextPage(int currentPage, gE&f}M-
7~&Y"&
int totalPage){ tj0vB]c
return currentPage == totalPage || totalPage == T>?~eYHXs
v|xlI4
0 ? false : true; )Jc>l;G(M
} 8"@<s?0\"
c?d#Bj ?
y-U(`{[nM
} <KpQu%2(
W[jxfZD9v
ocMf}"
! 9e>J
TsD
>m
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。 UpITx]y?"m
qhtc?A/0}
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 ch&r.
M3''xrpC
做法如下: _C4^J
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Vl EkT9^:
5^xt/vYa)
的信息,和一个结果集List: P/_XDP./U
java代码: N P"z
W)l&4#__(
TcC=_je460
/*Created on 2005-6-13*/ 5q<kt{06\
package com.adt.bo; 'D4NPG`z
H|^4e
import java.util.List; yD KX,
&$=F$
import org.flyware.util.page.Page; [Yv5Sw
FR <wp
/** >eXNw}_j
* @author Joa )-9/5Z0v
*/ S.I<Hs
publicclass Result { IoX(Pa
xnLf R6B
private Page page; 5u&jNU5m_
vD(;VeW[
private List content; 1~*_H_Q't
k91Y"_&
/** qUo(hbp
* The default constructor 1ID!rxE
*/ >[p+L='
public Result(){ #8`G&S*
super(); vL><Y.kOEs
} e0qa~5
AkF1Hj
/** >hXUq9;:
* The constructor using fields Y,a.9AWw)
* e#AB0-f
* @param page
[W;14BD7
* @param content 8'YL!moG|
*/ Y8d%L;b[D
public Result(Page page, List content){ <sTaXaq?
this.page = page; (/)JnBy0
this.content = content; 1?*vqdt
} Kq1sGk
bi5'- .B
/** X0lIeGwrQ
* @return Returns the content. Uq&|iB#mF
*/ HiWZ?G
publicList getContent(){ V +hV&|=
return content; %jkd}D
} -uh/W=Q1R
=gj]R
/** w#o<qrpHf
* @return Returns the page. w90y-^p%
*/ H'Po
public Page getPage(){ Q:-/@$&i
return page; Ghj6&K%b0
} )S`A+M K]
U9@q"v-
/** OZ-F+#d
* @param content }3+(A`9h f
* The content to set. ]M2> %Dvw
*/ @}[)uH
public void setContent(List content){ n"Ev25%
this.content = content; f[z#=zv
} _x:K%1_[
^awl-CG
/** 'r-a:8:t^
* @param page UgUW4x'+
* The page to set. yXkgGY5
*/ ;eWVc;H
publicvoid setPage(Page page){ Qdtfi1_Y1
this.page = page; Zw }7vD0
} |~>8]3. Y
} Wima=xYe\5
f[X>?{q
s*S@}l
c xX
Z{e5 OJ
2. 编写业务逻辑接口,并实现它(UserManager, j\W+wnAgk
8*|@A6ig
UserManagerImpl) \Oc3rJ(
java代码: 6#.R'O
F[J;u/Z
_)p%
/*Created on 2005-7-15*/ r^]0LJ
package com.adt.service; NE/3aU
DB?[h<^m
import net.sf.hibernate.HibernateException; t4,6`d?C
D L$P
import org.flyware.util.page.Page; {6~W2zX&
d`2VbZC`
import com.adt.bo.Result; V{(ve#y7`{
V+E2nJ
/** |vGz
1jLV
* @author Joa zRu}lJ1#W$
*/ d,$[633It}
publicinterface UserManager { Q~`]0R159e
^D\#*pIO
public Result listUser(Page page)throws ]0\8g=KK
}J:~}?^%n
HibernateException; K+n6.BzW
;zs4>>^>
} c1Dhx,]ad
lS}5bcjR=k
4,uH 4[7
|3vQmd !2}
In]h+tG?rN
java代码: (3W<yAM+
"bRck88V
m,Os$>{Ok
/*Created on 2005-7-15*/ j#o0y5S
package com.adt.service.impl; p;U[cGHC
@| qnD
import java.util.List; >{$;O
"-90:"W
import net.sf.hibernate.HibernateException; Xo;J1H
rmk'{"
import org.flyware.util.page.Page; -;_NdL@
import org.flyware.util.page.PageUtil; m%'9z L c
b8feo'4Z
import com.adt.bo.Result; 3q{H=6
import com.adt.dao.UserDAO; Lb{~a_c
import com.adt.exception.ObjectNotFoundException; #$e~o}(r
import com.adt.service.UserManager; 0[x?Q[~S_0
yAi#Y3!::
/** Bm;{dO
* @author Joa VABrw t
*/ vFV->/u
publicclass UserManagerImpl implements UserManager { vx5;}[Bhm
Hvnak{5
private UserDAO userDAO; sO~N2
^kch]?
/** ;yx+BaG~?
* @param userDAO The userDAO to set. Xa Yx avq
*/ HEhdV5B
publicvoid setUserDAO(UserDAO userDAO){ jCtl
]
this.userDAO = userDAO; 7=6p
} axxdW)+K
A!ba_14
/* (non-Javadoc) ~i=/@;wRp
* @see com.adt.service.UserManager#listUser d&n0:xOc
\@:pWe
(org.flyware.util.page.Page) K/,
B
*/ 44
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public Result listUser(Page page)throws UFyGp>/06
|0b$60m$!t
HibernateException, ObjectNotFoundException { !-|&
int totalRecords = userDAO.getUserCount(); n,9 *!1y
if(totalRecords == 0) O (tcu@vfl
throw new ObjectNotFoundException .]k(7F!W
/thCu%%9A
("userNotExist"); }V ;PaX
page = PageUtil.createPage(page, totalRecords); *O$kF.3q
List users = userDAO.getUserByPage(page); U@BVVH?,o
returnnew Result(page, users); b0rC\^x
} 7>9/bB+TL
Q5Y4@
} *[.+|v;A
E IsA2 f
OJbY\U
deda=%w0
YxGIv8O]
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 %Kw5b ;
'"GdO;}&
询,接下来编写UserDAO的代码: jO3Q@N0_
3. UserDAO 和 UserDAOImpl: Jn'q'+
java代码: [\ @!~F{
:>F:G%(DK
-x:Wp*,
/*Created on 2005-7-15*/ F2z^7n.S
package com.adt.dao; 4w*F!E2H\}
{pd%I
import java.util.List; ["Z]K'?P
D<5gdIw
import org.flyware.util.page.Page; uQ5NN*C=
FT[wa-b
import net.sf.hibernate.HibernateException; `axNeqM
|>j=#2
/** j<8_SD =,
* @author Joa h'MX{Wm.
*/ qAivsYN*
publicinterface UserDAO extends BaseDAO { e}(.u1
wD22@uM#]
publicList getUserByName(String name)throws Q\m"n^XN
31w?bx !Pp
HibernateException; ^q%~K{'`-
Q]{DhDz?+
publicint getUserCount()throws HibernateException; BL]!j#''KE
zw\"!=r^
publicList getUserByPage(Page page)throws rouD"cy
Sn7.KYS
HibernateException; oJ{)0;<~L
Vn=J$Uv0
} ]A<\d
]L}<Y9)t
;#~rd8Z52
CU lANd"
4>0xS-
java代码: SDA
+XnmH
G5TdAW
_$MoMg{uJH
/*Created on 2005-7-15*/ _ky!4^B
package com.adt.dao.impl; <ywxz1 i
GrVvOJr
import java.util.List; gl2~6"dc
^R>&^"oI
import org.flyware.util.page.Page; <9\_b6
B7?784{x,
import net.sf.hibernate.HibernateException; k}F ;e_
import net.sf.hibernate.Query; B:^5W{
Z|' tw^0e5
import com.adt.dao.UserDAO; B<8Z?:3YS
bL
swq
/**
M"X/([G
* @author Joa @>X."QbE
*/ /x0zZ+}V
public class UserDAOImpl extends BaseDAOHibernateImpl \W/cC'
m"H9C-Y
implements UserDAO { w
y:USS?
qI8{JcFx:
/* (non-Javadoc) "9>#Q3<N
* @see com.adt.dao.UserDAO#getUserByName 0BxO75m}o
~[k2(
(java.lang.String) Ddt(*z
/
*/ K'1rS[^>R
publicList getUserByName(String name)throws (8=Zr0He
;M@/AAZ
HibernateException { KZ/}Iy>As
String querySentence = "FROM user in class Xps MgJ/w
q SCt=eQ
com.adt.po.User WHERE user.name=:name"; )ae/+Q8
Query query = getSession().createQuery ew}C*4qH
b*?="%eE(
(querySentence); 6`X#<#_&
query.setParameter("name", name); ;}^Pfm8
return query.list(); Q\ro )r
} hj0uv6t.c
(MJu3t
@
/* (non-Javadoc) (Ozb +W?
* @see com.adt.dao.UserDAO#getUserCount() V,
)kw{](
*/ I-fs*yzj;8
publicint getUserCount()throws HibernateException { |iO2,99i
int count = 0; h'IBVI!P
String querySentence = "SELECT count(*) FROM ~~'XY( \L@
`9b D%M
user in class com.adt.po.User"; mIl^
Query query = getSession().createQuery 4s0>QD$J
NZdQz
(querySentence); 1Voo($q.
count = ((Integer)query.iterate().next .\*\bvyCw
{9'"!fH
()).intValue(); |l7e*$j
return count; b>I -4
} w7w$z_P
"6Ly?'HK
/* (non-Javadoc) O{SU,"!y
* @see com.adt.dao.UserDAO#getUserByPage ~mmI]
pC
!Y`nKC(=z
(org.flyware.util.page.Page) 3lA<{m;V
*/ "+Xwc+v^
publicList getUserByPage(Page page)throws !=k\Rr@qx
K6!`b(
v#
HibernateException { UI>-5,X
String querySentence = "FROM user in class B3XVhUP
|MTgKEsn
com.adt.po.User"; `I_%`1 5>
Query query = getSession().createQuery _xUiHX<
(VwS9:`
(querySentence); q&
4Z.(
query.setFirstResult(page.getBeginIndex()) %o+bO}/9
.setMaxResults(page.getEveryPage()); VaSw}q/o:/
return query.list(); 9I30ULm
} K& 2p<\2
+z("'Cv
} o.}^6.h"
E(]yjZ/
(WN 'wp
%#ms`"H
~iF*+\
至此,一个完整的分页程序完成。前台的只需要调用 "LXLUa03
98o;_tU'
userManager.listUser(page)即可得到一个Page对象和结果集对象 @RbAC*Y]g
/=[M
的综合体,而传入的参数page对象则可以由前台传入,如果用 V/>SjUNq
YfF&: "-NU
webwork,甚至可以直接在配置文件中指定。 7fnKe2MM
K2:r7f
下面给出一个webwork调用示例: owYfrf3ZLX
java代码: ^b>E_u
90I)"vfW5
bis/Nfr]
/*Created on 2005-6-17*/ y%ER51+
package com.adt.action.user; Wu.od|t0
~3f#cEP>d}
import java.util.List; Er{[83
jnH44
import org.apache.commons.logging.Log; t$Irr*
import org.apache.commons.logging.LogFactory; 3^1)W!n/
import org.flyware.util.page.Page; \EB]J\x<
fp12-Hk ~
import com.adt.bo.Result; uVOpg]8d
import com.adt.service.UserService; 2Ni{wg"
import com.opensymphony.xwork.Action; a7#Eyw^H{
-uO< ]
/** _eO+O=j_x
* @author Joa )S8q.h
*/ l*% voKZG
publicclass ListUser implementsAction{ d5^ipu
b;!ilBc
privatestaticfinal Log logger = LogFactory.getLog K7e<hdP_#
:GL|:
(ListUser.class); n!HFHy2
H@aCo(#
private UserService userService; fjp>FVv3
m{+lG*
private Page page; #docBsHX&s
B(^fM!_%-6
privateList users; |U7{!yy%MF
2$1rS}}
/* }zLe;1Tx
* (non-Javadoc) BKvF,f/g
* o2Pj|u*X
* @see com.opensymphony.xwork.Action#execute() \?qXscq
*/ 1egryp
publicString execute()throwsException{ [ ddEt
Result result = userService.listUser(page); ]]d@jj
page = result.getPage(); <;U"D.'
users = result.getContent(); XTZWbhNF
return SUCCESS; y)(SS8JR
} UbQeN
~@got
/** j&8 ~X2?*
* @return Returns the page. B8a!"AQ~5
*/ D-,sF8{ i
public Page getPage(){ 6[qRb+ds
return page; !+fHdB
} MgtyO3GUAD
sBSBDjk[
/** *r9I
1W
* @return Returns the users. f#X`e'1
*/ k?xtZ,n{s
publicList getUsers(){ ^OA}#k
NTW
return users; "aa6W
} 88G[XkL$2
!' sDqBZ&7
/** jq =-Y
* @param page 8E0Rg/DnT
* The page to set. 5~.\rcr%
*/ r0S7e3xb
publicvoid setPage(Page page){ X.UIFcK^
this.page = page; K"=v|a.
} Tmw
:w~
S2fw"1h*x
/** u\t ;
* @param users 8n&" ,)U
* The users to set. .3HC*E.e
*/ J-\b?Ra
publicvoid setUsers(List users){ 8{d`N|k
this.users = users; $6'xRUx X
} 1eb1Lvn
uHf~KYL
/** Ap97 Zcw
* @param userService @cjhri|vH
* The userService to set. |]m&LC
*/ I1}{7-_t
publicvoid setUserService(UserService userService){ txL5'mK
this.userService = userService; -z|idy{
} -rH3rKtf~
} c6lEWC:
a)Wf* <B
2r*
o
q_ 5xsTlTR
'2.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, ~F' $p
,cm2uY
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 @Sv
?Ar
<B`=oO%o
么只需要: 6,c,i;J_
java代码: wCI.jGSBW
B2,!
0Re
m&$H?yXW>
<?xml version="1.0"?> Nq9(O#}
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork M>vM@j
sJ0y3)PQ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- >ZNL
pJQ
D(r|sw
1.0.dtd"> UW>~C
}~ +
<xwork> mS);bs
`9wz:s QtP
<package name="user" extends="webwork- ]#*@<T*[
@FbzKHdV/
interceptors"> hrXN38-
<"\K|2Sg
<!-- The default interceptor stack name M!I:$DZt
}`h}h<B(
--> ^iI^)
<default-interceptor-ref UIu'x_qc
O=-|b kO
name="myDefaultWebStack"/> S>*T&K
Cu`ZgKLQ
<action name="listUser" WUHx0I
%WO;WxG8^
class="com.adt.action.user.ListUser"> kKj YMYT6
<param r7IhmdA
7C 4Njei"
name="page.everyPage">10</param> w6E?TI
<result OsK=% aDpj
,)Q mQ^/
name="success">/user/user_list.jsp</result> 2R5]UR S
</action> 3'']q3H
(Ux%7H_d
</package> F`ihw[
Wn
Cn_Mz#Z
</xwork> :]//{HF
^L'K?o
vw(};)8
ec3('}X
ct]5\g?U'
)kd)v4#
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 V3`*LU
A] F K\
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。 cfj6I
jAJkCCG
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 5q)Eed
r`&ofk1K
("TI~
,{oANqP
+fwq9I>L
我写的一个用于分页的类,用了泛型了,hoho gVD!.
UtWoSFZ'o!
java代码: x/Ds`\
PCU6E9~t2
\fKv+
package com.intokr.util; &/zsIx+
Y Jv{Z^;M
import java.util.List; V]<dh|x
b"zq3$6*
/** r!zNcN(%cs
* 用于分页的类<br> OC[a?#R1
* 可以用于传递查询的结果也可以用于传送查询的参数<br> s9'iHe
* HD`%Ma
Yhc
* @version 0.01 yy>4`_
* @author cheng HN3
yA1<[V
*/ &{
f5F7E@
public class Paginator<E> { xA-G&oC]<T
privateint count = 0; // 总记录数 s+CWyW@
privateint p = 1; // 页编号 ud.S,
8Sy
privateint num = 20; // 每页的记录数 G)putk@
privateList<E> results = null; // 结果 %]
Bb;0G
Bq _<v)M*
/** G +YF
* 结果总数 :l7\7IT
*/
+FJ
o!~1
publicint getCount(){ F6 UOo.L)I
return count; f{+8]VA
} v` B_xEl
%d=-<EQ|&
publicvoid setCount(int count){ ^@)+P/&
this.count = count; g%+nMjif
} ?,Hk]Rl3
PC3wzJ\\S
/** YZnrGkQ
* 本结果所在的页码,从1开始 @!F9}n
AP
* Pjx9@i
* @return Returns the pageNo. @ce4sSo
*/ Q;Oc#
u
publicint getP(){ $]hf2Yr(
return p; &556 ;l
} UM#]olh
n
XQg(!
/** k4`v(au^
* if(p<=0) p=1 qNvKlwR9;k
* Mr&]RTEE
* @param p co*5NM^
*/ co12\,aD
publicvoid setP(int p){ 0m@S+$v
if(p <= 0) N*z<VZ
p = 1; 'DIE#l`
this.p = p; q6,xsO,+
} %tu{`PN<
11)~!in
/** w68qyG|wM
* 每页记录数量 tC&y3!k2jR
*/ JD>!3>S)?
publicint getNum(){ N1SR nJu<f
return num; gF:wdcO
} ]>:>":<:
E+>;tLw3j
/** [F>zM
* if(num<1) num=1 NR3IeTd
*/ ^@ux
publicvoid setNum(int num){ (z.Vwl5
if(num < 1) R52!pB0[
num = 1; Sj*H4ZHD<&
this.num = num; 9V;m;sz
} `W/6xm(X5;
?K]k(ZV_+Y
/** mHhm~u
* 获得总页数 O8lOr(|l
*/ &wjOb
publicint getPageNum(){ |;].~7^
return(count - 1) / num + 1; &fTCY-W[
} |)lo<}{
DnTM#i:
/** i0R=P[
* 获得本页的开始编号,为 (p-1)*num+1 ;J_d%
*/ h0gT/x
publicint getStart(){ ^.4<#Qs
return(p - 1) * num + 1; $~j]/ U
} gf!j|O ;
a(
qw
/** b!N`@m=
* @return Returns the results. C/cyqxVl}
*/ O=mJ8W@
publicList<E> getResults(){ /q^( uWu
return results; 6D+9f{~r
} t9=rr>8)
M"J$c42
public void setResults(List<E> results){ ZE1#{u~[y
this.results = results; 6tJM*{$$H
} ugL$W@
[m4<j
public String toString(){ c2y5[L7?
StringBuilder buff = new StringBuilder ,JjTzO
%>s y`c
(); P--#5W;^oB
buff.append("{"); 7_|zMk.J*
buff.append("count:").append(count); ;TR.UUT
buff.append(",p:").append(p); Q[k}_1sWs$
buff.append(",nump:").append(num); V^Nc0r
buff.append(",results:").append SAqX[c
'Kq%tM26!
(results); 7[K$os5al
buff.append("}"); rj6wKfz
return buff.toString(); :|Z*aI]9
} 1M+mH#?
Ltu;sw
} [bZXzV(
N#UyAm<9
{>~|xW