Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ]}cai1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 k|,pj^
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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 FG-w7a2mn
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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 QtQku1{
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分页支持类: Xz0jjO,
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java代码: A?3hNvfx
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package com.javaeye.common.util; )kl| 5i
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import java.util.List; hFP$MFab
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publicclass PaginationSupport { 50(/LV1
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publicfinalstaticint PAGESIZE = 30; n\5` JNCb
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privateint pageSize = PAGESIZE; viAvD6e
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privateList items; ]YZ+/:#U7
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privateint totalCount; > >wbyj8
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privateint[] indexes = newint[0]; fM_aDSRa!H
= Ow}MX
privateint startIndex = 0; fEdQR->
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public PaginationSupport(List items, int O: sjf?z
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totalCount){ LGPy>,!
setPageSize(PAGESIZE); {SW104nb
setTotalCount(totalCount); |,5b[Y"Dt
setItems(items); 4-=> >#
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setStartIndex(0); \w^iSK-
} t-lWvxXe
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public PaginationSupport(List items, int Vf*!m~]Vqi
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totalCount, int startIndex){ :N%cIxrqP
setPageSize(PAGESIZE); /H@k;o
setTotalCount(totalCount); WKqNJN C
setItems(items); cg<10KT
setStartIndex(startIndex); o)cd!,h
} r~u/M0h `
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public PaginationSupport(List items, int ,>2ijk#
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); e6k}-<W*q
setTotalCount(totalCount); |t|+pBB
setItems(items); z['>`Kt
setStartIndex(startIndex); *4r
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} 9">}@1k
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publicList getItems(){ NyJU?^f&v
return items; Q}W6?XDu
} 09 eS&J<R
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publicvoid setItems(List items){ 6CLrP}
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this.items = items; 95aa
} 2;5EH0
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publicint getPageSize(){ V{$(#r
return pageSize; r`i<XGPJ%
} -Duy:C6W
+%6{>C+bZo
publicvoid setPageSize(int pageSize){ S3:Pjz}t
this.pageSize = pageSize; 0(ZER sP
} <m`HK.|~
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publicint getTotalCount(){ z*l3O~mZ
return totalCount; P
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} A"\kdxC
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publicvoid setTotalCount(int totalCount){ Vur$t^zE
if(totalCount > 0){ ,`G8U/
this.totalCount = totalCount; VCcLS3
int count = totalCount / i15uHl
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pageSize; - P1OD)B
if(totalCount % pageSize > 0) 8Cs)_bj#!
count++; q0.+ F4
indexes = newint[count]; ^P~%^?(
for(int i = 0; i < count; i++){ U'UV=:/-
indexes = pageSize * }/[tB
={W;8BUV%^
i; "dXRUg"
} 4!d&Zc>C4
}else{ Q{UR3U'Q
this.totalCount = 0; Zb8Ty~.\P
} F5wCl2I
} qWGnIPk
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publicint[] getIndexes(){ x$J1%K*
return indexes; 2+TCFpv
}
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publicvoid setIndexes(int[] indexes){ :qc@S&v@]
this.indexes = indexes; U GQ{QH
} {%9)l,
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publicint getStartIndex(){ S WVeUL#5
return startIndex; =2\k
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} nY'0*:'u
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publicvoid setStartIndex(int startIndex){ y!6B Gz
if(totalCount <= 0) ANc)igo
this.startIndex = 0; kTAb
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elseif(startIndex >= totalCount) ixw3Z D(>+
this.startIndex = indexes &xgMqv2/
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[indexes.length - 1]; s&iM.[k
elseif(startIndex < 0) ~jH@3\
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this.startIndex = 0; D*o_IrG_(
else{ Q`4=
this.startIndex = indexes f/~"_O%
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[startIndex / pageSize]; EQSOEf[
} ,@tkL!"9q
} 5:Pp62
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publicint getNextIndex(){ $]%;u: Sa
int nextIndex = getStartIndex() + 4vT!xn
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pageSize; r )ZUeHt}w
if(nextIndex >= totalCount) }Xr-xh\v
return getStartIndex(); w0)V3
else 4[
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return nextIndex; {2vk<
} lTvI;zy
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publicint getPreviousIndex(){ ]{{A/ j\
int previousIndex = getStartIndex() - OKNA36cU'
YFv/t=`
pageSize; nW3-)Q89
if(previousIndex < 0) yMq&9R9F
return0; UQ:H3
else ;o8C(5xE|
return previousIndex; ,=O`'l>K
} AV Gu*
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} !jN}n)FSq
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抽象业务类 g34<0%6jd
java代码: K]Q#B|_T
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/** <gF=$u|}3[
* Created on 2005-7-12 J0*hJ-/u
*/ S_/9eI~X
package com.javaeye.common.business; rdhK&5x*
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import java.io.Serializable; t.$3?"60~
import java.util.List;
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import org.hibernate.Criteria; hEi]-N\X
import org.hibernate.HibernateException; 'iA#lKG
import org.hibernate.Session; GwQW
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import org.hibernate.criterion.DetachedCriteria; k__i Jsk
import org.hibernate.criterion.Projections; XAwo~E
import oGM Ls
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org.springframework.orm.hibernate3.HibernateCallback; Q1jU{
import Ig}G"GR
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org.springframework.orm.hibernate3.support.HibernateDaoS k"\%x=#
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upport; Aayh'xQ
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import com.javaeye.common.util.PaginationSupport; g6{.C7m
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public abstract class AbstractManager extends ig<Eyr
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HibernateDaoSupport { _8P"/(
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privateboolean cacheQueries = false; 0]4kR8R3[
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privateString queryCacheRegion; [Oen{c9A
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publicvoid setCacheQueries(boolean 5LdVcXf
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cacheQueries){ m^0r9y,
this.cacheQueries = cacheQueries; w`=_|4wFw
} rt%?K.S/
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publicvoid setQueryCacheRegion(String '?=SnjMX
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queryCacheRegion){ W2/FGJD
this.queryCacheRegion = #N^TqOr
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queryCacheRegion; =F'p#N0_2
} -1iKeyyA
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publicvoid save(finalObject entity){ 9pUvw_9MY
getHibernateTemplate().save(entity);
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} :f%FM&b
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publicvoid persist(finalObject entity){ VN[C%C
getHibernateTemplate().save(entity); 59mNb:<
} K~ ,|~
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publicvoid update(finalObject entity){ s3qWTdM
getHibernateTemplate().update(entity); nfpkWyI u{
} `q|&;wP.
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publicvoid delete(finalObject entity){ **_`AM~
getHibernateTemplate().delete(entity); D,q=?~
} g?`g+:nug
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publicObject load(finalClass entity, Go~bQ2*'(/
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finalSerializable id){ arJ4^ d
return getHibernateTemplate().load :MeshzWK
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(entity, id); ^,u0kMG5l
} |T?wM/
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publicObject get(finalClass entity, Ay)q %:qx
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finalSerializable id){ R}Pw#*B
return getHibernateTemplate().get [M>Md-pj
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(entity, id); 88}+.-3t$
} 7'u<)V
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publicList findAll(finalClass entity){ %pj6[x`@
return getHibernateTemplate().find("from PN9^ sLx=
u.;zz'|
" + entity.getName()); ^kZfE"iE2
} {Hncm
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publicList findByNamedQuery(finalString xg=}MoX
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namedQuery){ =B4,H=7Spf
return getHibernateTemplate HUqG)t*c1
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().findByNamedQuery(namedQuery); F*V<L
} <!b~7sZkTc
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publicList findByNamedQuery(finalString query, ' =MaO@ @
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finalObject parameter){ r@C2zF7
return getHibernateTemplate P^m+SAAB
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().findByNamedQuery(query, parameter); n8<o*f&&9>
} dFY]~_P472
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publicList findByNamedQuery(finalString query, ]jbQou@
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finalObject[] parameters){ g8^\|
return getHibernateTemplate W>C!V
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().findByNamedQuery(query, parameters); dWHl<BUm
} v|5:;,I
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publicList find(finalString query){ +mRFHZG
return getHibernateTemplate().find /H#- \r&r
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(query); a*LT <N
} YnnpgR.
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publicList find(finalString query, finalObject csn/h$`-@
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parameter){ TDI8L\rr
return getHibernateTemplate().find wMy$T<:
m"Y;GzqQl
(query, parameter); xml@]N*D#E
} 49f- u
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public PaginationSupport findPageByCriteria kp3(/`xP
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(final DetachedCriteria detachedCriteria){ Gvo(iOU
return findPageByCriteria (Wkli:Lq
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Y"
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} ?DcR D)X
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public PaginationSupport findPageByCriteria gfQ&U@N
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(final DetachedCriteria detachedCriteria, finalint #PnuR2s7.
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startIndex){ }* iag\
return findPageByCriteria ?wE@9g A
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(detachedCriteria, PaginationSupport.PAGESIZE, ~~:w^(s9
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startIndex); W-wy<<~f
} u2HkAPhD
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public PaginationSupport findPageByCriteria rQiX7
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(final DetachedCriteria detachedCriteria, finalint * d6[kY
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pageSize, ';`fMcN
finalint startIndex){ Ke-Q>sm2Q
return(PaginationSupport) M0!;{1
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getHibernateTemplate().execute(new HibernateCallback(){ N[4v6GS
publicObject doInHibernate }HS:3Dt
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(Session session)throws HibernateException { @C)O[&Sk
Criteria criteria = lhg3
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detachedCriteria.getExecutableCriteria(session); E_&Hje|J_[
int totalCount = ".L+gn}u-
9fD4xkRS
((Integer) criteria.setProjection(Projections.rowCount )/k0*:OMyO
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()).uniqueResult()).intValue(); @k~?h=o\b
criteria.setProjection ToNi<~
8?] :>
(null);
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List items = eydVWVN
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criteria.setFirstResult(startIndex).setMaxResults 8D]:>[|E
n+@}8;oeP
(pageSize).list(); -oq!zi4:
PaginationSupport ps = GZT}aMMSJ
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new PaginationSupport(items, totalCount, pageSize, 1"46OCu{
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startIndex); .lu:S;JSnS
return ps; Rde_I`Ru
} >4TJH
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}, true); FzmCS@yA
} k*|dX.C:
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public List findAllByCriteria(final Wu)ATs}
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DetachedCriteria detachedCriteria){ SCeZt [
return(List) getHibernateTemplate RAKQ+Y"nl
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().execute(new HibernateCallback(){ 9[DQ[bL
publicObject doInHibernate nPq\J~M
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(Session session)throws HibernateException { sBuJK'
Criteria criteria = LLmgk"
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detachedCriteria.getExecutableCriteria(session); a:@9GmtV&
return criteria.list(); vy/U""w`
} rh2pVDS
}, true); 7ka^y k@Q
} OXDlwbwL
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public int getCountByCriteria(final lp[3z&u
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DetachedCriteria detachedCriteria){ =f@O~nGm
Integer count = (Integer) ih`/1n
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getHibernateTemplate().execute(new HibernateCallback(){ q?z6|]M|u
publicObject doInHibernate $n `Zvl2
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(Session session)throws HibernateException { yp5*8g5
Criteria criteria = 3M{!yPlj
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detachedCriteria.getExecutableCriteria(session); (Wr;:3i
return :{4G=UbAI
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criteria.setProjection(Projections.rowCount +C;ZO6%w
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()).uniqueResult(); !|_
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} MIa].S#
}, true); <0P`ct0,i
return count.intValue(); EC1q#;:
} ,2JqX>On>Y
} GQqw(2Ub}
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用户在web层构造查询条件detachedCriteria,和可选的 w%S<N
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @usQ*k
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PaginationSupport的实例ps。 PB>p"[ap4
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ps.getItems()得到已分页好的结果集 N(vbo
ps.getIndexes()得到分页索引的数组 OpxVy _5,
ps.getTotalCount()得到总结果数 I#eIm3Y?
ps.getStartIndex()当前分页索引 R,Zuy(g
ps.getNextIndex()下一页索引 hD<z^j+
ps.getPreviousIndex()上一页索引 ?d+B]VYw
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 v{
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 V EY !0PIj
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一下代码重构了。 ,_NO[+5U
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我把原本我的做法也提供出来供大家讨论吧: 6$PfX.Fh
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首先,为了实现分页查询,我封装了一个Page类: CyG @
java代码: w** .8]A"N
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/*Created on 2005-4-14*/ D{N1.rSxv
package org.flyware.util.page; pMt]wyKr
([f6\Pw\ <
/** x?CjRvT$
* @author Joa pvmm" f
* yWzvE:!)
*/ )Xd=EWGUS
publicclass Page { GsDSJz
QQ2xNNF[
/** imply if the page has previous page */ ^|\ *i
privateboolean hasPrePage; KD,b.s
YY7:WQS
/** imply if the page has next page */ !&Q,]\j
privateboolean hasNextPage; 2gt08\
*<9 D]
/** the number of every page */ I$f:K]|.m!
privateint everyPage; }d.R=A9L
$,i:#KT`
/** the total page number */ Gw+z8^|C&}
privateint totalPage; EVq<gGy
S}Mxm2
/** the number of current page */ 8(3vNuyP
privateint currentPage; 1&jX~'
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/** the begin index of the records by the current ;uoH+`pf
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query */ "#4PU5.
privateint beginIndex; I">z#@CT
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/** The default constructor */ uaU!V4-
public Page(){ 7ZZSAI
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} P45q}v
ke3=s
/** construct the page by everyPage a S<JsB
* @param everyPage 6 Dg[b
* */ h@W}xT
public Page(int everyPage){ |d%Dw^
this.everyPage = everyPage; 8l='H l
} ;U20g:K
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/** The whole constructor */ PFPfLxna
public Page(boolean hasPrePage, boolean hasNextPage, sXhtn'<v
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int everyPage, int totalPage, .mok.f<G_m
int currentPage, int beginIndex){ m%Ef]({I
this.hasPrePage = hasPrePage; kN}.[enI~
this.hasNextPage = hasNextPage; l>=c]
this.everyPage = everyPage; @F,HyCSN
this.totalPage = totalPage; zb;'}l;+
this.currentPage = currentPage; l>qCT
this.beginIndex = beginIndex; L\-T[w),z7
} q>Q|:g&:
siD Sm
/** .5dZaI)
* @return @Rx/]wyH
* Returns the beginIndex. Hfc^<q4a.
*/ {qx"/;3V
publicint getBeginIndex(){ ,/d-o;W
return beginIndex; KO5Q;H
} " g_\W
CiMy_`H
/** 3i s.c)
* @param beginIndex J| 'T2g
* The beginIndex to set. o1n c.2/0J
*/ B]Zsn`n
publicvoid setBeginIndex(int beginIndex){ LG,RF:
this.beginIndex = beginIndex; ^
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} n:#ji|wM
C&5T;=<jKO
/** y!v $5wi
* @return gH_r'j
* Returns the currentPage. +- .BF"}
*/ 1%-?e``.
publicint getCurrentPage(){ _aDx('
return currentPage; <4O=[Q 5S
} Lqch~@E&%#
.
}=;]=
/** Jx{,x-I
* @param currentPage X,OxvmDm
* The currentPage to set. %
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*/ X`aED\#\h
publicvoid setCurrentPage(int currentPage){ .7kVC
this.currentPage = currentPage; N7;E 2 X
} i5AhF\7F9
-_314j=`/
/** +QHhAA$
* @return >K
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* Returns the everyPage. '.dW>7
*/ t 1&p>
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publicint getEveryPage(){ ar^`r!ABEh
return everyPage; pixI&iQ
} ' l!QGKz
SjJUhTb
/** 7P \sn<
* @param everyPage FcWu#}.p}
* The everyPage to set. B[$SA-ZHi
*/ &1?Q]ZRp
publicvoid setEveryPage(int everyPage){ DX!$k[
this.everyPage = everyPage; 6g.@I!j E
} )b-G2< kb
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/** FCP5EN
* @return X'u`\<&W
* Returns the hasNextPage. |BW956fBU
*/ 'rF TtT
publicboolean getHasNextPage(){ 9<YB&:<
return hasNextPage; )8k6GO8|
} nut7b
,2cw9?<
/** h5Z\9`f[
* @param hasNextPage ZU@V]+ww
* The hasNextPage to set. |aVv Lz
*/ un/eS-IIh
publicvoid setHasNextPage(boolean hasNextPage){ D=OU61AA
this.hasNextPage = hasNextPage; >N3{*W
} MD
On; Af>
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/** qMUqd}=P
* @return g_x<+3a
* Returns the hasPrePage. '+eP%Y[W%
*/ h]=chz
publicboolean getHasPrePage(){ )l"0:1I g
return hasPrePage; S4(IYnwN
} S_QDYnF)`
t^[{8,N
/** 2`},;i~[
* @param hasPrePage bc"{ZL!C
* The hasPrePage to set. ECSC,oJ
*/ Hv=coS>g:
publicvoid setHasPrePage(boolean hasPrePage){ YW'Y=*
this.hasPrePage = hasPrePage; _9-Ajv
} ]I]dwi_g)
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t8"
/** EtL=_D-
* @return Returns the totalPage. 'Oc8[8
* @2u<Bh}}
*/ J)-owu;
publicint getTotalPage(){ 7]^Cg;EtM:
return totalPage; *\`C!r
} Q\rqG
8t^"1ND
/** hh?'tb{
* @param totalPage ,S8Vfb &
* The totalPage to set. ysa"f+/
*/ 6RF01z|~_
publicvoid setTotalPage(int totalPage){ *H$nydQ:
this.totalPage = totalPage; W`\H3?C`xQ
} ~\/ J&
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} G]S E
A
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s,}<5N]U
sDF J
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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 CJC|%i3
\x+DEy'4;5
个PageUtil,负责对Page对象进行构造: @<2pYIi8
java代码: *p-Fn$7\n
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/*Created on 2005-4-14*/ kal8k-$#
package org.flyware.util.page; s=$ 7lYX
nqH^%/7)A@
import org.apache.commons.logging.Log;
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import org.apache.commons.logging.LogFactory; -`RJk(
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/** s%:fB(
* @author Joa y>OZ<!`
* MPB6
*/ zZxP=
c
publicclass PageUtil { T'V(%\w
]`NbNr]K
privatestaticfinal Log logger = LogFactory.getLog *Z]|
Z4Q/`
NqWHR~&
(PageUtil.class); Z:*U/_G
aw 7f$Fqk
/**
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* Use the origin page to create a new page lfA
BF
* @param page <,GHy/u\
* @param totalRecords vBpg6
fX
* @return ~;+vF-]R
*/ MJb = +L
publicstatic Page createPage(Page page, int 5bw]cv$i
H>r-|*n
totalRecords){ Wf?sJ`.%b
return createPage(page.getEveryPage(), U\[V !1O
4A&e+kz&:R
page.getCurrentPage(), totalRecords); 1Q%.-vs
} gB"Tc[l1
:+5afv}
/** gv,T<A?Z2
* the basic page utils not including exception <\8
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handler U&5zs r
* @param everyPage W
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* @param currentPage ]UI+6}r
* @param totalRecords t[maUy_A
* @return page >R:+ml
*/ b[k 1)R"
publicstatic Page createPage(int everyPage, int GlZ9k-ZRF
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currentPage, int totalRecords){ 5 QeGx3'
everyPage = getEveryPage(everyPage); jysV%q 3
currentPage = getCurrentPage(currentPage); Dmi;# WY
int beginIndex = getBeginIndex(everyPage, ;Y'\:
</Id';|v
currentPage); n96gDH*
int totalPage = getTotalPage(everyPage, Fs|;>Up0
YUb,5Y0
totalRecords); {|gJC>f@
boolean hasNextPage = hasNextPage(currentPage, 9H}&Ri%
Z)A+ wM
totalPage); V[M#qZS
boolean hasPrePage = hasPrePage(currentPage); acZHb[w
6'ZnyWb
returnnew Page(hasPrePage, hasNextPage, M;Rw]M
everyPage, totalPage, ]*@$%iCPE
currentPage, HH#i.s2
/RC!Yi
beginIndex); :U q]~e
} _e_%U<\4
Sg$\ab $
privatestaticint getEveryPage(int everyPage){ %MJ7u}
return everyPage == 0 ? 10 : everyPage; &-:yn&f7
} l{U 3;
6y_Z'@L
privatestaticint getCurrentPage(int currentPage){ [J`G`s!
return currentPage == 0 ? 1 : currentPage; F"H!CJJu&
} DG\YZV4
Uq.~3V+u
privatestaticint getBeginIndex(int everyPage, int N]}+F w\5
5ecz'eA%
currentPage){ }tZAU\z
return(currentPage - 1) * everyPage; N)*e^Nfb
} ug,|'<G+
D:E_h
privatestaticint getTotalPage(int everyPage, int ?v8k& q^q
"V0:Lq
totalRecords){ 7 !.8#A':
int totalPage = 0; "T
u[n\8
$0SZlq>En
if(totalRecords % everyPage == 0) ebe@.ZVSi
totalPage = totalRecords / everyPage; -l@W)?$
else b=UMoWS
totalPage = totalRecords / everyPage + 1 ; 4.B*B3
vx@p;1RU`
return totalPage; [Be53U{=
} dO;vcgvb
xg^^ @o
privatestaticboolean hasPrePage(int currentPage){ @%nUfG7TQ
return currentPage == 1 ? false : true; xJLO\B+gM
} TY\"@(Q|G
Z{4aGp*
privatestaticboolean hasNextPage(int currentPage, AdW2o|Uap
rOHW
int totalPage){ TQd FC\@f"
return currentPage == totalPage || totalPage == Q|KD/s??
[0ffOTy
0 ? false : true; Ju7C?)x
} $cK
B+}
zZc@;S#
_1> 4Q%
} }!]x|zU.=
yO;C3q
p}DF$k%`
xO-U]%oq
+7<>x-+
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。 bM0[V5:jB
NND=Zxl
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 !K3cf]2UD
(E}cA&{
做法如下: *.]E+MYi*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >X,Ag
fEG3b#t N
的信息,和一个结果集List: Gi2ad+QH-
java代码: H\+c'$
? < O
T5jG IIa
/*Created on 2005-6-13*/ *t M7>
package com.adt.bo; {&EZ>r-
I/V )z9
import java.util.List; zO5u{
$%%>n^??
import org.flyware.util.page.Page; vZeYp
$`5lvy^
/** "]s|D@^4#b
* @author Joa {/A)t1nL
*/ a!y,!EB+Qu
publicclass Result { /D$+b9FR<
k?/ v y9
private Page page; 3).o"AN
:n4:@L<%H
private List content; +>:}req
27],O@2?L
/** /1W7<']>xV
* The default constructor n*i'v tQ8
*/ ow+Dd[i
public Result(){ y^QYlZO
super(); A]iv)C;]
} k g,ys4
hHc^ZA
/** RQpIBsj
* The constructor using fields 2WPF{y%/
* i$JG^6,O
* @param page a][pTC\ rb
* @param content W-!Bl&jF[
*/ %- ZR~*
public Result(Page page, List content){ { 0%TMiVf
this.page = page; :#\B {)(
this.content = content; ,t%\0[{/B
} 8PoHBOxpc
du'}+rC
/** CaYos;Pl
* @return Returns the content. MLt'YW^
*/ U +*oI *
publicList getContent(){ Z6R:
rq
return content; xQ#Akd=
} (9KDtr*(2i
=(.mf
/** Rnj Jg?I=
* @return Returns the page. 5]H))}9>d
*/ l$-=Pqb
public Page getPage(){ YBtq0c
return page; "y~muE:.
} "$W|/vD+
q:
TT4MUj<
/** b=K6IX;
* @param content Tr+h$M1_Ja
* The content to set. S!jF:Uc
*/ 5 dfe@$
public void setContent(List content){ UH 47e
this.content = content; /o|PA:6J
} xTJSr2f
pkXfsi-Nu
/** Z6IJ o%s
* @param page H~?*KcZ 0\
* The page to set. L}}=yh6r
*/ =mKfFeO.
publicvoid setPage(Page page){ Q{AZ'XV
this.page = page; ~U"by_
} Mhb '^\px
} H@%7\g,`
vo(g0Au)
pcI&
bkr~13S{+
q GpP,
2. 编写业务逻辑接口,并实现它(UserManager, I|g@W_
lh,ylh
UserManagerImpl) ?w]"~
java代码: A6^p}_
?kL|>1TY
1V|< A
/*Created on 2005-7-15*/ ( zn_8s
package com.adt.service; 5q5 )uv"
"UQr :/
import net.sf.hibernate.HibernateException; Gur8.A;Y
V[o7Jr~
import org.flyware.util.page.Page; UAsF0&]
SON^CvMs{
import com.adt.bo.Result; ;x:k-s2-
6R 1wn&8
/** ku/\16E/k
* @author Joa
Ws-6W!Ib%
*/ y|q@;*rGNa
publicinterface UserManager { jlu`lG*e&
(NH8AS<
public Result listUser(Page page)throws @-'/__cgt
^M`>YOU2+
HibernateException; jo9J%vo
`zdH1 p^w
} N]1V1c$G*
1YOg1 n+k
$}qDV>
qo
%f3c7\=C
*Q bM*oH
java代码: Pm$F2YrO3
#4vV%S
`Y\gSUhzS
/*Created on 2005-7-15*/ yGb a
package com.adt.service.impl; F&=I7i
; cGv] A+
import java.util.List; U9 1 &|
k2EHco0BG
import net.sf.hibernate.HibernateException; K :1g"
oM6j>&$b
import org.flyware.util.page.Page; ^cYStMjpy
import org.flyware.util.page.PageUtil; h&)fu{
3jvx2
import com.adt.bo.Result; r5t;'eCea
import com.adt.dao.UserDAO; _*O7l
import com.adt.exception.ObjectNotFoundException; 3p:=xL
import com.adt.service.UserManager; Z5((1J9
F(#ha J$>
/** EkN_8(w
* @author Joa WMW1B}Z3
*/ J'oDOn.M
publicclass UserManagerImpl implements UserManager { 8';m)Jc
fv|]= e
private UserDAO userDAO; QB!jLlg(
PeO] lq
/** /_]ltX D
* @param userDAO The userDAO to set. :W~6F*A
*/ o^HNF+sm
publicvoid setUserDAO(UserDAO userDAO){ Z}|TW~J=
this.userDAO = userDAO; b<[jaI0
} xC<=~(
_b>F#nD,'%
/* (non-Javadoc) ):e+dt
* @see com.adt.service.UserManager#listUser J!rY
6[t
?#d6i$
(org.flyware.util.page.Page) \I?w)CE@R
*/ {}V$`L8
public Result listUser(Page page)throws DhZ:#mM{
e"]"F{Q
HibernateException, ObjectNotFoundException { Eu|sWdmf
l
int totalRecords = userDAO.getUserCount(); TI}}1ScA'
if(totalRecords == 0) {S G*
throw new ObjectNotFoundException Sa L"!uAk
+}P%HH]E/p
("userNotExist"); <"<Mbbp
page = PageUtil.createPage(page, totalRecords); 85'nXYN{d
List users = userDAO.getUserByPage(page); Y=r!2u6r~
returnnew Result(page, users); *R BV'b
} )D;*DUtMVm
~e{H#*f&1/
} Rq) 0i}F
JjQ8|En
T'E]
i!$
2+z1h^)W
)B6# A0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 uS~#4;R
4CLsY n?
询,接下来编写UserDAO的代码: n=q=zn;
3. UserDAO 和 UserDAOImpl: 7AFE-'S
java代码: hi!`9k
%dc3z"u
.;9jdGBf
/*Created on 2005-7-15*/ ]Kv q |}=
package com.adt.dao; `ruNA>M
^K+:C;Q|
import java.util.List; |XRImeF'd
5k]XQxc6_
import org.flyware.util.page.Page; [u`6^TycP
f-4.WW2FN
import net.sf.hibernate.HibernateException; +td<{4oq8
9e!vA6Fx
/** -IadHX}]t
* @author Joa n@hl2M6.x9
*/ >L gVj$Z
publicinterface UserDAO extends BaseDAO { xRlYr# %
/Y,r@D
publicList getUserByName(String name)throws F|Q H
3V?817&6z
HibernateException; ) V36t{
1]T|6N?
publicint getUserCount()throws HibernateException; {6h|6.S2
%]!adro~
publicList getUserByPage(Page page)throws obO}NF*g^
u^=`%)
HibernateException; T?n-x?e
WWNu:,
} kx:jI^
GX
}q9
/4*W DiH
#jBN?Z#
=s;M]:
java代码: KVN"XqE4
[[WF0q
!;v.>.lw
/*Created on 2005-7-15*/ OUI6
ax\[
package com.adt.dao.impl; u`_*g^5q"
pISp*&
import java.util.List; $
KB
,(N[*)G
import org.flyware.util.page.Page; }^Gd4[(,g
:_xh(W+2<
import net.sf.hibernate.HibernateException; &$=! dA
import net.sf.hibernate.Query; */(I[p
px=]bALU
import com.adt.dao.UserDAO; E)W@{?.o#
o_f-GO
/** e4\dpvL
* @author Joa T_LLJ}6M
*/ $'{=R 45Z
public class UserDAOImpl extends BaseDAOHibernateImpl jnJZ#=)
:U'Cor
H
implements UserDAO { $shp(T,q
X:EEPGE
/* (non-Javadoc) 7C7>y/uS
* @see com.adt.dao.UserDAO#getUserByName 7O)" `
#H~_K}Ks
(java.lang.String) \S ."?!U
*/ booRrTS
publicList getUserByName(String name)throws .TpsJXF
Xgat-cy'DA
HibernateException { [/|zH'j:
String querySentence = "FROM user in class =sgdkAYwP
<41ZZ0<EwY
com.adt.po.User WHERE user.name=:name"; NmpnJu|8
Query query = getSession().createQuery [=uIb._Wv
eg<pa'Hw
(querySentence); Zb_apjg[4
query.setParameter("name", name); =:=/Gz1
return query.list(); `s"d]/85VW
} MsOs{2
)2
w5,Mb
/* (non-Javadoc) [syj#
* @see com.adt.dao.UserDAO#getUserCount() hH>``gK
*/ G$bJ+
publicint getUserCount()throws HibernateException { !yJICjXj
int count = 0; ,SUT~oETP
String querySentence = "SELECT count(*) FROM )d`mvZBn1
Da.G4,vLh
user in class com.adt.po.User"; Ak@Dyi?p
Query query = getSession().createQuery [
MyE2^
UzG[:ic%
(querySentence); mJ5H=&Z
count = ((Integer)query.iterate().next ldqLM
FwG!>
()).intValue(); <RXw M6G2
return count; ny*i+4Mb
} h8{(KRa 6
B&0;4
/* (non-Javadoc) =&nW~<- v
* @see com.adt.dao.UserDAO#getUserByPage ,Nm$i"Lg
ZDt?j
(org.flyware.util.page.Page) k N7Bd}
*/ Bc5+ss
publicList getUserByPage(Page page)throws 5B4Ssrs5W~
p3(2?UO!
HibernateException { R2<s0l
String querySentence = "FROM user in class w@-M{?R
xHA0gZf
com.adt.po.User"; Fc 6iQ
Query query = getSession().createQuery 'b&yrBFD
zM#sOg
(querySentence); 8LzBh_J?
query.setFirstResult(page.getBeginIndex()) u<xo/=Z
.setMaxResults(page.getEveryPage()); =r2]uW9
return query.list(); I/6)3su%
} N2C7[z+l`
hz:pbes
} U/ od~29
fmX!6Kv
r6Aneg7
Yk!/ow@.
0RFRbi@n(
至此,一个完整的分页程序完成。前台的只需要调用 nh+l78
Z4b||
userManager.listUser(page)即可得到一个Page对象和结果集对象 4?\:{1X=
49H+(*@v@
的综合体,而传入的参数page对象则可以由前台传入,如果用 !69&Ld
WKfkKk;G
webwork,甚至可以直接在配置文件中指定。 &7e)O=
qet>1<
下面给出一个webwork调用示例: 8^/I>0EZ
java代码: X}ma]
WJH\~<{mP
!]yO^Ob.E
/*Created on 2005-6-17*/ KngTc(^_D
package com.adt.action.user; zAzP,1$?
mHc>"^R
import java.util.List; FS6`6M.K
as yZe
import org.apache.commons.logging.Log; 2Os1C}m
import org.apache.commons.logging.LogFactory; q? qC
import org.flyware.util.page.Page; H,unpZ(
I#F!N6;
import com.adt.bo.Result; nI.x
import com.adt.service.UserService; `l;n:]+
import com.opensymphony.xwork.Action; /D&%v*~E
Rhc-q|Lz8
/** FY{e2~gi
* @author Joa CC=d I
*/ Mn1Pt|_@!
publicclass ListUser implementsAction{ aT!'}GjL
nfSbM3D]h
privatestaticfinal Log logger = LogFactory.getLog nn/?fIZN4
Hb} X-6N
(ListUser.class); H %JaZ?(
K.<.cJE
private UserService userService; i9<pqQ
Q_-_^J
private Page page; _|[UI.a
^hNgm.I
privateList users; ajR%c2G;
IJYL s
/* !G^L/?z3
* (non-Javadoc) c#-U%qZ
* wI]"U2L5
* @see com.opensymphony.xwork.Action#execute() tz4
]qOH8
*/ ^z1&8k"[^
publicString execute()throwsException{ kft#R#m
Result result = userService.listUser(page); %,Sf1fUJ
page = result.getPage(); 3s\.cG?`r
users = result.getContent(); 3$.deYa$R
return SUCCESS; 0R{dNyh{
} X[
q+619
3vhnwDcK
/** "k*PA\U
* @return Returns the page. gVQjL+_W
*/ CYYkzcc^
public Page getPage(){ `ps)0!L
L`
return page; uH/w\v_I
} Y}#h5\
t@u7RL*n:<
/** Dd;Nz
* @return Returns the users. (?_S6HE
*/ #e'
}.4cr
publicList getUsers(){ -F'b8:m
return users; 8Ac)'2t;U
} Bm&kkx.9P
3_~cMlr3T.
/** yjfat&$
* @param page Eskb9^A
* The page to set. 7VcmVq}X
*/ =mA: ctu~v
publicvoid setPage(Page page){ }ci#>
this.page = page; 3 "o"fl
} 'smWLz}
8} =JKR^cK
/** nF6q7
* @param users nKW*Y}VO
* The users to set. x77l~=P+!
*/ fP.F`V_Y
publicvoid setUsers(List users){ PV|uPuz
this.users = users; ^Ge+~o?x
} j'9"cE5_
i4^o59}8
/** #fT*]NN
* @param userService XsnF~)YW
* The userService to set. D8
hr?:I9
*/ =Umw$+fJr
publicvoid setUserService(UserService userService){ sB;@>NY
this.userService = userService; (aD_zG=k5
} sC9&Dgkk
} TMYd47
I\YV des#
PO6&bIr
m0v:\?S:
&f&z_WU
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, J_s>N
<.Nx[!'~&d
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 G:zua`u[
H54R8O$
么只需要: 2W4qBaG$=
java代码: JV;OGh>
]T%rjsN
6Cn+e.j@
<?xml version="1.0"?> _i/t?7
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _YF%V;X
HttiX/2~
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *Z|y'<s
Yo[;W
vu
1.0.dtd"> qWmQ-|Py
"~D]E7Q3y
<xwork> E9;|'Vy<E
(\SA*.)
<package name="user" extends="webwork- _q~=~nub
ANgw"&&>(
interceptors"> 9W(dmde>
1Tu
*79A
<!-- The default interceptor stack name .'Vww
8']9$#
--> s8}@=]aA
<default-interceptor-ref #5V9oKM
uDEvzk42
name="myDefaultWebStack"/> hZ.Z3`v70
L:FoSCN Y(
<action name="listUser" 'nF2aD%A
k+ze74_"
class="com.adt.action.user.ListUser"> T<XA8h*
<param ih7/}
\EVBwE,
name="page.everyPage">10</param> U\Z?taXB
<result qHxqQ'ks;
=5\|[NSK-
name="success">/user/user_list.jsp</result> je!-J8{
</action> daYx76yP_?
@HOBRRm`
</package> ~JaAii{
%Ah^E$&n2
</xwork> ra
o[VZ
V3"=w&2]K
5=f|7yl
KN*
z_|/5$T>U
hNzB4p
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 |o\8
y~FV2$
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。 h=:Q-?n-
}I
:OsAw
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 XHK70: i
^/r7@:
m@^1JlH
DCZ\6WY1G)
yxH ( c
我写的一个用于分页的类,用了泛型了,hoho ?Orxmxc
2
t2lS
~l)
java代码: QDu 2?EYZq
o#skR4lwe
Rb.SY{}C
package com.intokr.util; uXKERzg
Ry'= ke
import java.util.List; _A=$oVe
1&-
</G#
/** )'~6HO8Z
* 用于分页的类<br> ={z*akn,
* 可以用于传递查询的结果也可以用于传送查询的参数<br> RRI"d~~F6
* -:na:Vsi
* @version 0.01 a]MX)?
* @author cheng % ClHCoyA
*/ ;dJ1
public class Paginator<E> { |>#{[wko
privateint count = 0; // 总记录数 O<,\^[x
privateint p = 1; // 页编号 k3uit+ge}
privateint num = 20; // 每页的记录数 LbkF
privateList<E> results = null; // 结果 GSRVe/[
!7kG!)40
/** O)jWZOVp >
* 结果总数 ,]d,-)KX8
*/ f`;j:O
publicint getCount(){ uB]b}"+l
return count; >M`CVUf
} bdc&1I$
s#WAR]x0x
publicvoid setCount(int count){ bLwAXW2K+
this.count = count; iB498t
} 3J5!oF{H
^3UGV*Ypk
/** 2'W<h)m)z
* 本结果所在的页码,从1开始 >Vwc3d
* hK_LEwd;
* @return Returns the pageNo. <?@NRFTe
*/ 3h *!V6%q
publicint getP(){ F 9@h|#an
return p; sn)3ZA
} 6=fSE=]DY
aL&n[
/** o:_Xv.HRZo
* if(p<=0) p=1 W`u[h0\c
* SF>c\eTtx
* @param p pNKhc#-w
*/ kYjGj,m"
publicvoid setP(int p){ ,d {"m)r<
if(p <= 0) iy%ZQ[Un
p = 1; dfij|>:*0
this.p = p; 8]U{;|';
} egq67S
E/%9jDTQ
/** HxIIO[h
* 每页记录数量 Y9&,t\ q
*/ rl#p".4q
publicint getNum(){ BBtzs^C|
return num; 3G(miP6
} P7{gfiB
Uk6HQQ
/** x;8A!8w
* if(num<1) num=1 AD|2qM))
*/ ~x]jB
publicvoid setNum(int num){ 70eb]\%
if(num < 1) <c2'0I >
num = 1; `pGa~!vl
this.num = num; lx[oaCr
} ,"HL~2:~
7eV
di*
/** ;e1ku|>$
* 获得总页数 U
15H2-`
*/ <|SRe6m
publicint getPageNum(){ b)e
*$)
return(count - 1) / num + 1; [O?z@)dx
} 5nKj
)RH7M
R5X.^u
/** BEre*J
* 获得本页的开始编号,为 (p-1)*num+1 !Ikt '5/
*/ ]% IT|/;9Y
publicint getStart(){ hMykf4
return(p - 1) * num + 1; v#U"pn|M
} 7G/1VeVjB
/assq+H
/** {/
BT9|LI
* @return Returns the results. "gDb1h)8
*/ =*r])Vg^
publicList<E> getResults(){ CnG+Mc^
return results; 3_MS.iM
} i? K|TC`
}x07^4$j
public void setResults(List<E> results){ !qM=a3
this.results = results; yFtd=AI'E
} %nV]ibp2)
Cd>WUw
public String toString(){ "O%gFye
StringBuilder buff = new StringBuilder LC'{p
!BOY@$Y
(); %)0*&a 4
buff.append("{"); R]RZq+2^
buff.append("count:").append(count); \E*d\hrl{
buff.append(",p:").append(p); 3%(N[&LU
buff.append(",nump:").append(num); id2j7|$,
buff.append(",results:").append F7O(Cy"1
i5CK*"$Q
(results); CTZh0x
buff.append("}"); A^y|J`k|
return buff.toString(); }wHW7SJ
} 6{^E{go
Is{KN!Hw
} 5*,f
Fib
u (em&M
&8g?4v