Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Z^fkv
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +VN&kCx)
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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 (|*CVI;
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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 ,[Bv\4Ah
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分页支持类: )J['0DUrZK
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java代码: $;1TP|
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package com.javaeye.common.util; }H>}v/
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import java.util.List; \?|FB~.Ry
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publicclass PaginationSupport { 1&wI*4
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publicfinalstaticint PAGESIZE = 30; @5C!`:f
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privateint pageSize = PAGESIZE; LzS)WjEN
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privateList items; l-} );zH74
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privateint totalCount; y1FE +EX[
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privateint[] indexes = newint[0]; 5V{>
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privateint startIndex = 0; &F!Ct(c99
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public PaginationSupport(List items, int uxKj7!(#
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totalCount){ zj+.MG04
setPageSize(PAGESIZE); q>E[)\+y
setTotalCount(totalCount); "s6\l~+9l
setItems(items); da,Bnze0
setStartIndex(0); A:?|\r
} y9#r
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public PaginationSupport(List items, int P`HDQ/^O
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totalCount, int startIndex){ ;ye5HlH}.
setPageSize(PAGESIZE); [s"e?Qee
setTotalCount(totalCount); _@gd9Fi7J
setItems(items); |_Tp:][mf
setStartIndex(startIndex); sgc pH
} X}W4dpU,
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public PaginationSupport(List items, int _!} L\E~
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totalCount, int pageSize, int startIndex){ TrEo5H ;
setPageSize(pageSize); Hkv4^|
setTotalCount(totalCount); .wb[cCUQ
setItems(items); bS!4vc1`2
setStartIndex(startIndex); $BPTk0Y
} @rV|7%u
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publicList getItems(){ 5xs GSoa+
return items; Kz>Bw;R(
} v95O)cC:W
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publicvoid setItems(List items){ LO&/U4:
this.items = items; Sp2<rI
} 1c%ee$Q
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publicint getPageSize(){ 3 utv
return pageSize; (9phRo)>
} u@{z
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publicvoid setPageSize(int pageSize){ 3rUuRsXn
this.pageSize = pageSize; )qL UHE=
} [2 yxTK
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publicint getTotalCount(){ bh~"LQS1
return totalCount; H E'1Wa0r
} ?uBZ"^'
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publicvoid setTotalCount(int totalCount){ ?##3E,
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if(totalCount > 0){ gjGKdTr'
this.totalCount = totalCount; I8s%wY9
int count = totalCount / ^Fe%1Lnt
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pageSize; V(^aG=TaW:
if(totalCount % pageSize > 0) )^)j=xs
count++; 6
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indexes = newint[count]; !go$J]T
for(int i = 0; i < count; i++){ + bU*"5"
indexes = pageSize * {+SshT>J
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} WC pCWtmy
}else{ L#}HeOEi[
this.totalCount = 0; D J:N
}
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} Hx|<NS0}_
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publicint[] getIndexes(){ F70_N($i
return indexes; wyVQV8+&>
} A;'*>NS
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publicvoid setIndexes(int[] indexes){ 6iZ:0y0t+6
this.indexes = indexes; U^@8ebv
} E;>BcPt5
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publicint getStartIndex(){ 7F;dLd'
return startIndex; ~*-%tFSv
} VGPBD-6)
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publicvoid setStartIndex(int startIndex){ Z{".(?+}1
if(totalCount <= 0) XoZw8cY
this.startIndex = 0; ,o{|W9
elseif(startIndex >= totalCount) 1yg5d9
this.startIndex = indexes #zL0P>P'a
N;6@f*3_i
[indexes.length - 1]; /ad]pdF
elseif(startIndex < 0) *}n)KK7aT
this.startIndex = 0; @S>$y5if
else{ )dMXn2O
this.startIndex = indexes ?;c&5'7ct
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[startIndex / pageSize]; KVC$o+<'`%
} |rhCQ"H
} DClV&\i=o
@ a$HJ:
publicint getNextIndex(){ TSp;VrOP
int nextIndex = getStartIndex() + bTrQ(qp
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pageSize; j0]|$p
if(nextIndex >= totalCount) /;K?Y#mf~j
return getStartIndex(); fho$:S
else >JWW2<
return nextIndex; UojHlTg#bT
} `~.0PnHf
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publicint getPreviousIndex(){ aV6l"A]
int previousIndex = getStartIndex() - M10u?
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pageSize; JOA_2qa>\
if(previousIndex < 0) Bp.z6x4
return0; -$8M#n,
else m$U rY(6d
return previousIndex; {Y p;R
} HJh9<I
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} tK$x=9M
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抽象业务类 ^9ZW}AAO
java代码: 3o>.Z;
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/** %mv9+WJN.
* Created on 2005-7-12 x,3oa_'E
*/ Ijs"KAW
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package com.javaeye.common.business; u3Jsu=Nx-
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import java.io.Serializable; pR
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import java.util.List; >UQ`@GdafR
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import org.hibernate.Criteria; ZYBK'&J4m
import org.hibernate.HibernateException; h>l
import org.hibernate.Session; d:x=g i!
import org.hibernate.criterion.DetachedCriteria; }&o*ZY-1
import org.hibernate.criterion.Projections; Lh M{d
import 6EeUiLd
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org.springframework.orm.hibernate3.HibernateCallback; 3}}#'5D
import 9kkYD
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org.springframework.orm.hibernate3.support.HibernateDaoS 'za4c4b*u
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upport; 'aWzam>
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import com.javaeye.common.util.PaginationSupport; wJ|wAS
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public abstract class AbstractManager extends xP1`FSO8=
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HibernateDaoSupport { ;zbF~5e
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privateboolean cacheQueries = false; f17pwJ~=
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privateString queryCacheRegion; +QqEUf<U*,
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publicvoid setCacheQueries(boolean |c]Y1WwDx
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cacheQueries){ Ff\U]g
this.cacheQueries = cacheQueries; 3j2% '$>E^
} jx=2^A/i2-
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publicvoid setQueryCacheRegion(String )I`6XG
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queryCacheRegion){ #\&jM
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this.queryCacheRegion = KL4Z||n
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queryCacheRegion; \\qw"w9
} n{~Ws^d
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publicvoid save(finalObject entity){ }tIIA"dZ
getHibernateTemplate().save(entity); GUe&WW:Sqk
} .&53WL[D|
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publicvoid persist(finalObject entity){ jocu=Se@
getHibernateTemplate().save(entity); 4Qr16,Us
} |7jUf$Q\p
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publicvoid update(finalObject entity){ T1@]:`&
getHibernateTemplate().update(entity); YdgaZJs
} LWb5C{
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publicvoid delete(finalObject entity){ #_tixg
getHibernateTemplate().delete(entity); 2<aBUGA
} pvJsSX
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publicObject load(finalClass entity, m|O7@N
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finalSerializable id){ .[-d( #l{l
return getHibernateTemplate().load C^po*(W6
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(entity, id); K"cN`Kj<*-
} 8"a[W3b
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publicObject get(finalClass entity, T
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finalSerializable id){ Ksq{=q-T
return getHibernateTemplate().get dpO ZqhRs.
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(entity, id); -vXX u;frt
} F3\' WQh
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publicList findAll(finalClass entity){ *8zn\No<,
return getHibernateTemplate().find("from 7W[}7Y
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" + entity.getName()); ^/wvHu[#
} 1{oq8LB
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publicList findByNamedQuery(finalString a
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namedQuery){ |pv:'']J
return getHibernateTemplate Qa nE]
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().findByNamedQuery(namedQuery); JDi|]JY
} 9PA\Eo|Yb
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publicList findByNamedQuery(finalString query, b!Q|0X.?
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finalObject parameter){ M@rknq@
return getHibernateTemplate +'$=\d^
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().findByNamedQuery(query, parameter); &46h!gW
} .17WF\1HC.
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publicList findByNamedQuery(finalString query, 5-Vdq
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finalObject[] parameters){ SU.T0>w
return getHibernateTemplate Si#b"ls'
p/B&R@%
().findByNamedQuery(query, parameters); 5!r?U
} !M&L<0b:7e
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publicList find(finalString query){ \4q%
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return getHibernateTemplate().find AF4:v<EN
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(query); RLN>*X
} Gb6t`dSzz
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publicList find(finalString query, finalObject nz:I\yA
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parameter){ #`5{?2gS9
return getHibernateTemplate().find Ey$J.qw3
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(query, parameter); f%0^89)
} "VxZnT
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public PaginationSupport findPageByCriteria @Iz vObK
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(final DetachedCriteria detachedCriteria){ P SDzs\s
return findPageByCriteria CUgXpU*
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); &k+G^ !=s#
} Paz
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public PaginationSupport findPageByCriteria ~9JU_R^%m
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(final DetachedCriteria detachedCriteria, finalint UH1AT#?!W
@~0kSA7
startIndex){ 9"g=it2Rh6
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, > $0eRVL
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startIndex); N.OC _H&
} wkK61ah6
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public PaginationSupport findPageByCriteria c#M'Mye
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(final DetachedCriteria detachedCriteria, finalint ps1ndGp~#
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pageSize, beFVjVVHq
finalint startIndex){ rr fL[
return(PaginationSupport) U7d%*g
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getHibernateTemplate().execute(new HibernateCallback(){ J&w%lYiu5
publicObject doInHibernate K^bzZa+a
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(Session session)throws HibernateException { h%
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Criteria criteria = ;hi+.ng_
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detachedCriteria.getExecutableCriteria(session); &o$E1;og
int totalCount = euO!+9p
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((Integer) criteria.setProjection(Projections.rowCount f>i6f@
(SV(L~T_
()).uniqueResult()).intValue();
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criteria.setProjection (.a:jL$
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(null); _ETG.SYq
List items = +v:t
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criteria.setFirstResult(startIndex).setMaxResults 8jW{0&ox)
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(pageSize).list(); :Xc%_&)
PaginationSupport ps = Mi&,64<
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new PaginationSupport(items, totalCount, pageSize, 1UX"iOx(
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startIndex); jPg 8>Z&D
return ps; EzOO6
} 2@ vSe
}, true); xoI;s}*E
} [{e[3b*M|
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public List findAllByCriteria(final ;:Q 5?zM
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DetachedCriteria detachedCriteria){ I#QBJ#
return(List) getHibernateTemplate v#
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().execute(new HibernateCallback(){ O1IR+"0
publicObject doInHibernate = M^4T?{T
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(Session session)throws HibernateException { tbD>A6&VM}
Criteria criteria = /gh=+;{
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detachedCriteria.getExecutableCriteria(session); h')@NnFP1
return criteria.list(); S(Md
} <U`lh
}, true); M7{w7}B0@
} 8X`iMFa.P
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public int getCountByCriteria(final p%~#~5t,
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DetachedCriteria detachedCriteria){ @'`!2[2'?
Integer count = (Integer) S'qEBz
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getHibernateTemplate().execute(new HibernateCallback(){ TB9{e!4
publicObject doInHibernate ,-^Grmr4M
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(Session session)throws HibernateException { AFO g*{1
Criteria criteria = }z6@Z#%q
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detachedCriteria.getExecutableCriteria(session); <RY5ZP
return pUx~
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criteria.setProjection(Projections.rowCount MIvAugUOl
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()).uniqueResult(); r4/G&m[V
} p
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}, true); 3/V&PDC*'
return count.intValue(); .w3.zZ0[
} vcs=!Ace
} R{GOlxKs C
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用户在web层构造查询条件detachedCriteria,和可选的 B}_*0D
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 yi*)g0M
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PaginationSupport的实例ps。 O@r%G0Jge
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ps.getItems()得到已分页好的结果集 ~pA_E!3W
ps.getIndexes()得到分页索引的数组 dC8$Ql^<
ps.getTotalCount()得到总结果数 h<2o5c|
ps.getStartIndex()当前分页索引 x`K<z
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ps.getNextIndex()下一页索引 "&*O7cs$pA
ps.getPreviousIndex()上一页索引 SskvxH+7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 U_ n1QU
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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 v3!oY t:l
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一下代码重构了。 Ik2yIf5d
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我把原本我的做法也提供出来供大家讨论吧: 3T^f#UT
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首先,为了实现分页查询,我封装了一个Page类: l&l&eOE
java代码: UFBggT\
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/*Created on 2005-4-14*/ /H.w0fu&.S
package org.flyware.util.page; 94 58.!3
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/**
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* @author Joa c,nE@~ul2
* Hx[YHu
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*/ ax$ashFO/!
publicclass Page { ~<
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/** imply if the page has previous page */ KvENH=oh
privateboolean hasPrePage; J'c]':U
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/** imply if the page has next page */ jp=z
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privateboolean hasNextPage; |#9Nu9ak
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/** the number of every page */ r
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privateint everyPage; {I'8+~|pZL
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/** the total page number */ KZoIjK]
privateint totalPage; ~I[Z2&I
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/** the number of current page */ r4&g~+ck
privateint currentPage; pu#h:nb>88
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/** the begin index of the records by the current 50r3Kl0
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query */ Y,BzBUWK
privateint beginIndex; " B`k
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/** The default constructor */ 8R?X$=$]!.
public Page(){ O@.C.5Ep
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} r}351S5(
FW* k O
/** construct the page by everyPage =rSJ6'2("
* @param everyPage 8~*<s5H
* */ x!5b"
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public Page(int everyPage){ ;
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this.everyPage = everyPage; SOE5`
} 2I'gT$h
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/** The whole constructor */ $ 9bIUJ
public Page(boolean hasPrePage, boolean hasNextPage, %oPW`r
m? 3!
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int everyPage, int totalPage, c;siMWw;
int currentPage, int beginIndex){ <Y%km[Mh
this.hasPrePage = hasPrePage; 38ac~1HjE
this.hasNextPage = hasNextPage; Gy}WZ9{
this.everyPage = everyPage; 2to~=/.
this.totalPage = totalPage; |2RoDW
this.currentPage = currentPage; [+,%T;d;
this.beginIndex = beginIndex; :
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} \dvzL(,
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/** 6/{V#.(
* @return E"i<fr
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* Returns the beginIndex. %L;z ~C
*/ ',Y`XP"Q
publicint getBeginIndex(){ l Tpn/
return beginIndex; O3ij/8f
} gbvM2
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/** R1'tW=
* @param beginIndex kyV!ATL1F
* The beginIndex to set. vh+ '
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*/ %3p~5jhm1
publicvoid setBeginIndex(int beginIndex){ }
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this.beginIndex = beginIndex; nV`n=x
} DX3xWdnr
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/** Q\H1=8
* @return '7BJ.
* Returns the currentPage. >~%!#,C(|U
*/ *[XVkt`H
publicint getCurrentPage(){ =Sjr*)<@j
return currentPage; 87&BF)]
} YdgDMd-1
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/** r.-U=ql
* @param currentPage UXs=7H".
* The currentPage to set. v67utISNI
*/ H]]UsY`
publicvoid setCurrentPage(int currentPage){ %K9pnq/T^
this.currentPage = currentPage; .kbo]P
} Z\1*g k
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/** lI,lR
* @return Q4~/Tl;
* Returns the everyPage. [Eq7!_3
*/ |A .U~P):
publicint getEveryPage(){ {TmrWFo
return everyPage; n,,hE_
} #.Q3}[M
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/** a"ct"g=
* @param everyPage "6^~-`O
* The everyPage to set. (w1M\yodV
*/ .~3s~y*s
publicvoid setEveryPage(int everyPage){ ,Z3 (`ftC
this.everyPage = everyPage; B7'rbc'
} f{i~hVF
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/** R=7,F6.
* @return
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* Returns the hasNextPage. Re[x$rw
*/ So6ZNh9
publicboolean getHasNextPage(){ b\Wlpb=QZ
return hasNextPage; j<*
} 62-,!N 1-
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/** to2#PXf]y
* @param hasNextPage N~=,RPjq
* The hasNextPage to set. {pWb*~!k
*/ E \p Qh
publicvoid setHasNextPage(boolean hasNextPage){ Xl/SDm_p
this.hasNextPage = hasNextPage; rofGD9f
} $Gy&
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/** lwVo%-
* @return K3Sa6"U
* Returns the hasPrePage. S]"U(JmW\
*/ P0mY/bBU
publicboolean getHasPrePage(){ uT
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return hasPrePage; _VjfjA<c8
} *A^`[_y
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/** W5)R{w0`GD
* @param hasPrePage r
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* The hasPrePage to set. o[A y2"e?
*/ {M_*hR;lL
publicvoid setHasPrePage(boolean hasPrePage){ s^&Oh*SP*
this.hasPrePage = hasPrePage; =/#+,
} {s{bnU
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/** x$SxGc~4gb
* @return Returns the totalPage. <<SUIY@X
* vC
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*/
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publicint getTotalPage(){ qOqU
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return totalPage; Xn%ty@8
} H{d;,KfX
vvi[+$M
/** @$*LU:[
* @param totalPage VG=mA4Dd
* The totalPage to set. n5NwiSE
*/ sC}p_'L
publicvoid setTotalPage(int totalPage){ 78MQoG<
this.totalPage = totalPage; v1j&oA}$.
} > N bb0T
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} i"_@iN0N
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 H6oU Ne
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个PageUtil,负责对Page对象进行构造: 6Trtulm
java代码: !H^e$BA
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/*Created on 2005-4-14*/ AZ7m=Q97
package org.flyware.util.page; ~u.((GM
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import org.apache.commons.logging.Log; i]{-KZC
import org.apache.commons.logging.LogFactory; >qL-a*w:a
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/** ?= RC?K
* @author Joa 2mt
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* 3 q^^Os
*/ !uc"|S?
publicclass PageUtil { K\VL[HP-
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privatestaticfinal Log logger = LogFactory.getLog ytyX:e"
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(PageUtil.class); isR)^fI|
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/** %2ZWSQD
* Use the origin page to create a new page YVW`|'7)|
* @param page y?-zQs0
* @param totalRecords .QLjaEja
* @return KmX?W/%R
*/ *=)kR7,]9d
publicstatic Page createPage(Page page, int RQ*oTsq
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totalRecords){ A>Y#-e;<d
return createPage(page.getEveryPage(), #\T5r*W
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page.getCurrentPage(), totalRecords); p02E:?
} tPz!C&.=
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/** iebnQf
* the basic page utils not including exception LSlYYyt
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handler +\s&v!
* @param everyPage Mrly(*!U"@
* @param currentPage sIz*r Gz
* @param totalRecords :YUQKy
* @return page GS qt:<Qs
*/ V+>.Gf
publicstatic Page createPage(int everyPage, int pRc<U^Z.h
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currentPage, int totalRecords){ P+gYLX8
everyPage = getEveryPage(everyPage); N6<G`k,
currentPage = getCurrentPage(currentPage); \ sc's7
int beginIndex = getBeginIndex(everyPage, >mCS`D8
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currentPage); iZ;y(
int totalPage = getTotalPage(everyPage, m[$pj~<\
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totalRecords); "8*5!anu-
boolean hasNextPage = hasNextPage(currentPage, j= vlsW
(!:+q$#BK
totalPage); ~fz9AhU8
boolean hasPrePage = hasPrePage(currentPage); ^b&U0k$R
Rdj/n :
returnnew Page(hasPrePage, hasNextPage, oaGpqjBGQ
everyPage, totalPage, ;vp[J&=
currentPage, q'CtfmI`r=
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beginIndex); 3aERfIJyE
} C| g]Y 7
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privatestaticint getEveryPage(int everyPage){ jr3FDd]
return everyPage == 0 ? 10 : everyPage; b75en{aDi*
} t_NnQ4)=
vE$n0bL2
privatestaticint getCurrentPage(int currentPage){ 17) `CM$<[
return currentPage == 0 ? 1 : currentPage; ?3;0 SAh
} u0i;vO)MNt
w<$0n#5
privatestaticint getBeginIndex(int everyPage, int )D8V;g(7F
<wj}y0(
currentPage){ QQW]j;'~
return(currentPage - 1) * everyPage; oeF0t'%
} ~Blsj9a2
9`|~-b
privatestaticint getTotalPage(int everyPage, int 8i Xt8XY3
$e/[!3CASP
totalRecords){ kx6-8j3gD7
int totalPage = 0; /;V:<mekf
b6ui&Y8z
if(totalRecords % everyPage == 0) ,4Qct=%L_
totalPage = totalRecords / everyPage; .:A&5Y-
else
v7#`b}'W
totalPage = totalRecords / everyPage + 1 ; @z<IsAE
c?7Wjy
return totalPage; OqlP_^Zz7p
} BQF7S<O+
"iPX>{'En
privatestaticboolean hasPrePage(int currentPage){ r~Vb*~U"
return currentPage == 1 ? false : true; bX'.hHR
} "[Hn G(gA
x2.YEuSMC
privatestaticboolean hasNextPage(int currentPage, yl UkVr
rw%1>]os
int totalPage){ \\v1\
return currentPage == totalPage || totalPage == vQsI^p
Gid6,J
0 ? false : true; h $2lO^
} *sYvV,
;T\'|[bY
Vohd
d_x
} xt=ELzu$
V2/?1
K>S:Z
Rw]lW;EN<
A#x_>fV
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。 6<
@F
| \6Ff/O
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 DQyy">]Mh
NsUP0B}.
做法如下: Uk<2XGj
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 fiZq C?(
y*7<tj.`b0
的信息,和一个结果集List: qJ%AbdOI8
java代码: ?r/)s()ALf
U%H6jVE
q-R'5p\C?|
/*Created on 2005-6-13*/ (^9dp[2
package com.adt.bo; 2x<4&^
0o_wy1O1,
import java.util.List; -_+,HyJP
R,f"2
k
import org.flyware.util.page.Page; 3R)_'!R[B
\>lDM
/** ]mdO3P
* @author Joa ?CO..l
*/ D'Y=}I)8Dn
publicclass Result { xG~7kj3
&p_V<\(%
private Page page; Ew>lk9La(
$4u8"n e)
private List content; ![3l
K
%mr6p}E|
/** 84jA)
* The default constructor .u\xA7X
*/ Q@5v> `
public Result(){ i27KuPjC
super(); P^J #;{R
} D+('1E?
c!Wj^
/** b|E1>TkY
* The constructor using fields *7UDTgY
* -I*NS6
* @param page % h"%G=:
* @param content Y2>0Y3yM
*/ e%EE|
public Result(Page page, List content){ IZ3e:
this.page = page; zelM}/d
this.content = content; ;|AyP
} B~7]x;8h
WeE1 \
/** (8jQdbZU
* @return Returns the content. q~G@S2=}0}
*/ 1rGi"kdf
publicList getContent(){ %IHra6
return content; 3U&rK)F
} (ioJ G-2u
O~&j}WN
/** _ Y8jl,J
* @return Returns the page. J*m~fZ^
*/ 8c5%~}kG
public Page getPage(){ 2'5u}G9
return page; /Q\|u:oO,
} #5=!ew
WN3]xw3
/** DxJY{e9
* @param content 0p[-M`D
* The content to set. 4)+L(KyB2
*/ .y^T3?}I
public void setContent(List content){ 9KDm<Q-mf
this.content = content; ;k5B@z/<S
} 0S$6j-"
{<L|Z=&k`
/** '/
*;g#W=
* @param page x}X
hL
* The page to set. $Eh:m&hq
*/ PpWdZ
publicvoid setPage(Page page){ [28Vf"#]
this.page = page; i f !
} @D7/u88|
} :<i<\TH'
}-2U,Xg[
[s&0O<Wv
k btQ
)F65sV{
2. 编写业务逻辑接口,并实现它(UserManager, EJaGz\\
s]Qo'q2
UserManagerImpl) {RHa1wc
java代码: |rwx;+
9M Ug/
p n(y4we
/*Created on 2005-7-15*/ 4StoEgFS
package com.adt.service; ;$/]6@bqB
mWX{I2
import net.sf.hibernate.HibernateException; qz&?zzz;
u?lbC9}$
import org.flyware.util.page.Page; 5 ]l8l+
TpAso[r
import com.adt.bo.Result; ~Zo;LSI
@JU
Xp
/** prO ~g
* @author Joa IUSV\X9
*/ j+NsNIJq
publicinterface UserManager { -mqL[ h,
W~d^ *LZt
public Result listUser(Page page)throws 3fdqFJ O
w'zSV1
HibernateException; EKf! j3
CQ/ps,~M
} %{ +>\0x
`IH*~d]
~__rI-/_
).8NZ
Aj
!(#d7R
java代码: KSxZ4Y
"T1A$DKw+R
;>r
E+k%_
/*Created on 2005-7-15*/
p}(pIoyUF
package com.adt.service.impl; ZfnJ&H'
{q.|UCg[L
import java.util.List; 3%YDsd vQx
6h{>U*N"&d
import net.sf.hibernate.HibernateException; gX;)A|9e
8&c:73=?X
import org.flyware.util.page.Page; buA/G-<e
import org.flyware.util.page.PageUtil; IyoitIbLl
u
-A_l<K
import com.adt.bo.Result; wrAcVR
import com.adt.dao.UserDAO; bD<hzOa
import com.adt.exception.ObjectNotFoundException; H-jxH,mJmW
import com.adt.service.UserManager; (Ky$(Ubb#6
.'zcD^
/** `[F[0fY-
* @author Joa QR{>]I
*/ ,| ~Pa
publicclass UserManagerImpl implements UserManager { :YM1p&|fS
"P8(R
private UserDAO userDAO; OTD<3Q
q
#y*p7~|@
/** 5m9;'SF
* @param userDAO The userDAO to set. 3h**y
%^
*/ LjPpnjU
publicvoid setUserDAO(UserDAO userDAO){ WuMr";2*E
this.userDAO = userDAO; `P?!2\/
} R/Te;z
k]~|!`
/* (non-Javadoc) g4}K6)@
* @see com.adt.service.UserManager#listUser u$ff %`E
,Y`TP4Ip
(org.flyware.util.page.Page) w 3$9
*/ J8?V1Ad{
public Result listUser(Page page)throws jq(QL%)_O
wPl9%
HibernateException, ObjectNotFoundException { Tno 0Q
+
int totalRecords = userDAO.getUserCount(); B~47mw&b
if(totalRecords == 0) A+ LX37B
throw new ObjectNotFoundException h]DzX8r}
-~ H?R
("userNotExist"); {C5-M! D{<
page = PageUtil.createPage(page, totalRecords); #D
.hZ=!
List users = userDAO.getUserByPage(page); Oj#/R?%,X
returnnew Result(page, users); e|eWV{Dsz
} $Qcr8~+a
q*7:L
} z,c=."<z
H -t" Z}
s7s@!~
lX/:e=
wG
X\ub#!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Bj*
M
W
|Fe*t
询,接下来编写UserDAO的代码: Huf;A1.
3. UserDAO 和 UserDAOImpl: :ioD*k
java代码: E{]PfUfFY
D|g{]nO
o?S!o}
/*Created on 2005-7-15*/ d /lV+yZ
package com.adt.dao; X][=(l!;w7
fF.sT7Az+
import java.util.List; ][B>`gC-
s_cur-
import org.flyware.util.page.Page; KEo?Cy?%ff
<uvA([r=Vq
import net.sf.hibernate.HibernateException; mOntc6&]
Lrq e:\
/** RKb (
* @author Joa |vgYi
*/ Zb$P`~(%
publicinterface UserDAO extends BaseDAO { `!y/$7p
f[-$##S.~
publicList getUserByName(String name)throws 2q ~y\fe
V11XI<V
HibernateException; Eg4_kp0Lq
}ZJ*N Y
publicint getUserCount()throws HibernateException; A>%mJ3M
\?"p]&2UcB
publicList getUserByPage(Page page)throws qKk|2ecTB5
+ I4s0
HibernateException; "=!sZO?3
b=XHE1^rM
} f{)n xd
>#
YcN &\(
f}cCnJK
y=LN|vkQ
B~2M/&rM\
java代码: f7I!o,/
-;iCe7|Twf
s=hao4v7z
/*Created on 2005-7-15*/ qqSFy>`P
package com.adt.dao.impl; OPC8fX5.
xM**n3SZ`
import java.util.List; gmN$}Gy}
t>h:s3c
import org.flyware.util.page.Page; o_n 3.O=
dWiX_&g
import net.sf.hibernate.HibernateException; N1Dr'aw*
import net.sf.hibernate.Query; R})b%y`]
3o`c`;H%p
import com.adt.dao.UserDAO; 4P^CqD&i
v0KJKrliGO
/** k1~? }+<e
* @author Joa J*t_r-z
*/ mZ~f?{
public class UserDAOImpl extends BaseDAOHibernateImpl sE! $3|Q
HM &"2c
implements UserDAO { 3|=L1Pw#
@0-vf>e3-
/* (non-Javadoc) F"0=r
* @see com.adt.dao.UserDAO#getUserByName G$VE
o8Blb
8dwKJ3*.
(java.lang.String) IGF25-7B
*/ f0+vk'Z
publicList getUserByName(String name)throws Lmw4
_
qU-@Y$
HibernateException { <KFl4A~
String querySentence = "FROM user in class 2*a5pFkb
<aQ5chf7
com.adt.po.User WHERE user.name=:name"; }ZJJqJ`*e
Query query = getSession().createQuery d[oHjWk
f7:}t+d
(querySentence); ;lf $)3%[
query.setParameter("name", name); q_Z6s5O
return query.list(); Z6 E_Y?
} kY{;(b3Q
_ O;R
/* (non-Javadoc) \`R8s_S
* @see com.adt.dao.UserDAO#getUserCount() Fb6d1I^wR
*/ #~[{*[B+
publicint getUserCount()throws HibernateException { ^Vg-fO]V
int count = 0; 8/R9YiY5*
String querySentence = "SELECT count(*) FROM `o?PLE;)p
s&1}^'|
user in class com.adt.po.User"; v\D.j4%ij
Query query = getSession().createQuery {\gpXVrn_
gjk;An
(querySentence); vsJM[$RF
count = ((Integer)query.iterate().next VcLzv{
\i3)/sZ?l
()).intValue(); j+("4b'
return count; lr ]C'dD
} >1$Vh=\OI
'cA(-ghY/E
/* (non-Javadoc) .JV y}^Q\
* @see com.adt.dao.UserDAO#getUserByPage Rd[^)q4d$w
Y(=A HmR
(org.flyware.util.page.Page) w%- S5#
*/ h!?rk|
publicList getUserByPage(Page page)throws |IDZMd0
-Eoq#ULvR
HibernateException { L| ;WE=
String querySentence = "FROM user in class otlv;3263
R# ZO<g%'
com.adt.po.User"; *z&hXYm
Query query = getSession().createQuery +*wr=9>
t&~*!w!+jH
(querySentence); yz=aJ
v;
H
query.setFirstResult(page.getBeginIndex()) 8khIy-9-'
.setMaxResults(page.getEveryPage()); -PTfsQk
return query.list(); }^2'@y!(
} 10^FfwRfM
a#a n+JY3
} 5,?^SK|'x
B`:l;<&jX
"(Nt9K%P)
Fz' s\
1p8hn!V
至此,一个完整的分页程序完成。前台的只需要调用 T\"-q4+=C
"b) hj?
userManager.listUser(page)即可得到一个Page对象和结果集对象 &]pY~zVc
*W2o$_Hs
的综合体,而传入的参数page对象则可以由前台传入,如果用 c$x>6&&L
%DM0Z8P$B-
webwork,甚至可以直接在配置文件中指定。 8`_tnARIX
9I(00t_
下面给出一个webwork调用示例: Y]DC; ,
java代码: mJYD"WgY
A_crK`3
V3ExS1fNf
/*Created on 2005-6-17*/ <==6fc>s
package com.adt.action.user; gBOF#"-
Hyi'z 1
import java.util.List; odn3*{c{x
g} pD%
import org.apache.commons.logging.Log; %e:[[yq)G
import org.apache.commons.logging.LogFactory; h4Xz"i{z
import org.flyware.util.page.Page; PJ\k|
*,28@_EwY
import com.adt.bo.Result; 6Ad=#MM
import com.adt.service.UserService; L%+mD$@u
import com.opensymphony.xwork.Action; 8RQv
$laUkD#vz
/** ;vy<!@Y;8
* @author Joa e'->S g
*/ GP;N1/=
publicclass ListUser implementsAction{ FH%M5RD
^0-e.@
privatestaticfinal Log logger = LogFactory.getLog {W HK|l
dWdD^>8Ef
(ListUser.class); r1 b"ta
45&Rl,2
private UserService userService; {C0Y8:"`
[&kz4_
private Page page; d.HcO^
';v1AX}5q
privateList users; }}Z2@}
]^,! ;do
/* "C?H:8W
* (non-Javadoc) @9R78Zra
* Cj$:TWYIh[
* @see com.opensymphony.xwork.Action#execute() <W+9h0c
*/ AH_qZTv0{Q
publicString execute()throwsException{ Wb[k2V
Result result = userService.listUser(page); 3O;"{E=
<
page = result.getPage(); }Rw6+;
users = result.getContent(); X4{<{D`0t8
return SUCCESS; S&QXf<v
} BWNI|pq)v
t7Mq>rFB
/** JKy~'>Q
* @return Returns the page. pw`'q(ad
*/ UmY{2 nzY
public Page getPage(){ Ks<+@.DLTu
return page; k SgE_W)
} lQEsa45
Y[H769
/** (][-()YV
* @return Returns the users. x=+>J$~Pb
*/ +(y8q
publicList getUsers(){ tG ZMIG_
return users; v\_\bT1
} Sp*4Z`^je
q;UGiB^(A
/** yDWBrN._
* @param page #sxv?r
* The page to set. { {:Fs
*/ %ZX9YuXQ
publicvoid setPage(Page page){ :(wFNK/0{
this.page = page; k1ja ([Q
} /0$fYrg>J
(=%0$(S>
/** <fF|AbC:
* @param users -m@PqJF^
* The users to set. H:XPl$;
*/ [YZgQ
publicvoid setUsers(List users){ !0vLSF=
this.users = users; %V+"i_{m
} :H wdXhA6
EB*C;ms
/** P$Oj3HD LM
* @param userService }2iR=$2
* The userService to set. H5V>d
*/ *C<;yPVc
publicvoid setUserService(UserService userService){ ifu!6_b.
this.userService = userService; iJZNSRQJ}r
} EW1,&H
} GdY@$&z{i
v/=\(
>^GV
#z
|:.Uw\z5'
5[4nFa}R:5
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, C ocw%Yl
VBw5[
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 841 y"@*BY
-
jCj_@n
么只需要: ?$T ^L"~
java代码: w52py7
fGqX
dlP
AI|+*amTd
<?xml version="1.0"?> p$qk\efv*4
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork H%gAgXHn
UoKVl-
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ^+v1[U@
g(;OUkj$Zp
1.0.dtd"> ZWo~!Z [Y
Rb. vyQ
<xwork> 6>oc,=MV/
MIn_?r
<package name="user" extends="webwork- #o7)eKeQ
cjJfxD&q
interceptors"> +ima$a0Zyt
*YL86R+U
<!-- The default interceptor stack name '4<o&b^yQ
%ut8/T
--> q7f`:P9~
<default-interceptor-ref ft1#f@b.
"lLh#W1d
name="myDefaultWebStack"/> 6h2keyod
V7r_Ubg@K
<action name="listUser" JJ%@m;~
CbC[aVA=
class="com.adt.action.user.ListUser"> 1[8^JVC>6
<param i?;#ZNh
s)`(@"{
name="page.everyPage">10</param> bxtH`^
<result u}|v;:|j
#v<`|_
name="success">/user/user_list.jsp</result> X:$vP'B>
</action> yF?O+9R
A
ZTV)D
</package> t!*[nfR
1n[)({OQ
</xwork> 8.n#@%
vxTn
_:=\h5}8
z!O;s
ep?/
6V%}2YE?X
vt2.
i$u
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 G<D8a2q
hTzj{}w
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。 \<*F#3U1
(${ #l
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 &K[sb%
*$BUow/>
_.Hj:nFHz
`;+x\0@<
kSzap+ nB?
我写的一个用于分页的类,用了泛型了,hoho R20 .dA_N
G3io!XM)D
java代码: /MY's&D(
vj%"x/TP
{$hWz (
package com.intokr.util; nPdkvs
i .uyfV&F
import java.util.List; -dA9x~o
R/Bjc}J'
/** $cHU,
* 用于分页的类<br> W&)f#/M8
* 可以用于传递查询的结果也可以用于传送查询的参数<br> DxNob-Fr
* 2Ax"X12{6
* @version 0.01 Rw{'
O]Q*
* @author cheng z+7V}aPM
*/ bE.<vF&
public class Paginator<E> { 4@3 \Ihv
privateint count = 0; // 总记录数 c-(RjQ~M5
privateint p = 1; // 页编号 N,-C+r5}<4
privateint num = 20; // 每页的记录数 #p>&|I
privateList<E> results = null; // 结果 K~,!IU_QG
J<"K`|F
/** 5>.ATfAsV
* 结果总数 Ie/_gz^
*/ gfj_]
publicint getCount(){ (m:Q'4Ep
return count; ) hs&?:)
} \tYImh
jq% <Z,rh
publicvoid setCount(int count){ O}zHkcL
this.count = count; o#\L4P(J
} ~*/ >8R(Y
@i!+Z
/** F_'{:v1GW
* 本结果所在的页码,从1开始 UX63BA
* @3KSoA"^
* @return Returns the pageNo. )VkVZf | S
*/ klnNBo!
publicint getP(){
94PI
return p; dxAGO(
} ,$:u^;V(
.O1w-,=
/** nMzt_Il I
* if(p<=0) p=1 Hq 5#.rZ#
* ejZ-A?f-K
* @param p 4;J.$
*/ >~Zj
publicvoid setP(int p){ X}(X\rp
if(p <= 0) 5X)QW5A
p = 1; ~Ze!F"
this.p = p; IF6$@Q
} 8|)!E`TKSV
g$Y]{VM.J
/** :?zq!
* 每页记录数量 G{fPQ=
*/ ]vz6DJs
publicint getNum(){ 8%m\J:eR
return num; H"? 5]!p
} t;VMtIW+E
c=\ _[G(
/** wi7Br&bGi
* if(num<1) num=1 'yX\y
6I
*/ ;X+tCkzF
publicvoid setNum(int num){ e8> X5
if(num < 1) {AD-p!6G
num = 1; i*N2@Z[
this.num = num; Lm=EN%*#9
} RNw#sR
bT2c&VPCE
/** {U_ ,y(V
* 获得总页数 "KK}}$>
*/ ,H"}Rw
publicint getPageNum(){ 1q!k#Cliu
return(count - 1) / num + 1; 1$03:ve1
} 5*Zz_ .
^2$b8]q
/** YU-wE';H6
* 获得本页的开始编号,为 (p-1)*num+1 mvT/sC7I
*/ ~3j+hN8<
publicint getStart(){ oCOv
6(
return(p - 1) * num + 1; 5l8F.LtO\
} yJC:
bD1xi
6O{QmB0KK
/** >oJabR
* @return Returns the results. cQ- #]
*/ D? %*L
publicList<E> getResults(){ W)r|9G8T
return results; mv:@ D
} jRC{8^98
\Qah*1
public void setResults(List<E> results){ jm<^WQ%Cc
this.results = results; 0qFO+nC
} )
6QJZ$
c{1)-&W
public String toString(){ RP~67L
StringBuilder buff = new StringBuilder N*Q*>q
B">Ko3
(); [rcM32
buff.append("{"); <Nrtkf4-O
buff.append("count:").append(count); Pzzzv^+
buff.append(",p:").append(p); 4K:Aqqhds
buff.append(",nump:").append(num); Cj~e` VRhk
buff.append(",results:").append W895@
e"^WXP.t&
(results); h!(#
/
buff.append("}"); +sn0bi/rG
return buff.toString(); v2]N5
} ?SYmsaSr5
;U?=YSHk7
} W#g!Usf:/
I_8 n>\u
-!~pa^j