Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 `<#Ufi*c
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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 Ia@!Nr2
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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 |XrGf2P9u
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分页支持类: E*"-U!?)l2
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java代码: =".sCV9"N
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package com.javaeye.common.util; Ny" "lcy
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import java.util.List; j>I.d+
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publicclass PaginationSupport { vEZd;40y
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publicfinalstaticint PAGESIZE = 30; hfL8]d-
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privateint pageSize = PAGESIZE; b~td^
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privateList items; _8{6&AmIw
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privateint totalCount; &0Bs?oq_
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privateint[] indexes = newint[0]; Fo;.
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privateint startIndex = 0; +eVm+4WK
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public PaginationSupport(List items, int "8R\!i.
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totalCount){ b/g~;| <
setPageSize(PAGESIZE); /I@`B2
setTotalCount(totalCount); 6xW17P
setItems(items); ~E3"s
setStartIndex(0); VD0U]~CWR
} eFz!`a^dX
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public PaginationSupport(List items, int M1,1J-h
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totalCount, int startIndex){ d$<1Ma}
setPageSize(PAGESIZE); $1.l|
setTotalCount(totalCount); ]%<0V,G
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setItems(items); dx)v`.%V
setStartIndex(startIndex); E[8i$
} $E35W=~)
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public PaginationSupport(List items, int Q^|aix~ K
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totalCount, int pageSize, int startIndex){ pWN5 >HV
setPageSize(pageSize); |7:{vA5
setTotalCount(totalCount); 1g1gu=|Q
setItems(items); .{Df"e>
setStartIndex(startIndex); l
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} 'k!V!wcD^y
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publicList getItems(){ F^}n7h=qk
return items; V1>>]]PS
} .ta*M{t
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publicvoid setItems(List items){ DOGg=`XK1
this.items = items; v}^
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} qkh.?~
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publicint getPageSize(){ oQ_n:<3X
return pageSize; iT"H%{+~
} -E>se8 %"
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publicvoid setPageSize(int pageSize){ ey3;rY1
this.pageSize = pageSize; ,';+A{aV
} `Ef&h V
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publicint getTotalCount(){ YcJ2Arml
return totalCount; fP
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} {r?qI
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publicvoid setTotalCount(int totalCount){ $N`uM
if(totalCount > 0){ !kg)8 4C[
this.totalCount = totalCount; u#m(Py
int count = totalCount / iWNTI
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pageSize; qnZ`]?
if(totalCount % pageSize > 0) c&T14!lfn
count++; -?Aa RwZ,
indexes = newint[count]; ,*$/2nB^
for(int i = 0; i < count; i++){ Y)X58_En
indexes = pageSize * 6lc/_&0
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} E~|`Q6&Y
}else{ vDAv/l9
this.totalCount = 0; 4c_F>Jw[
} FE/2.!]&o
} +6*
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publicint[] getIndexes(){ :4D#hOI
return indexes; (~OwO_|3
} JIQzP?+?
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publicvoid setIndexes(int[] indexes){ @!MbPS
this.indexes = indexes; YG8oy!Zl
} M)xK+f2_[
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publicint getStartIndex(){ L9kP8&&KK
return startIndex; MJC
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} ;PHnv5 x@f
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publicvoid setStartIndex(int startIndex){ kp$ILZ
if(totalCount <= 0) m88~+o<G%
this.startIndex = 0; B';Ob
elseif(startIndex >= totalCount) ) )F.|w
this.startIndex = indexes Kaa*;T![
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[indexes.length - 1]; 9j"\Lr*o"
elseif(startIndex < 0) yS43>UK_W+
this.startIndex = 0; + ND9###
else{ mOB\ `&h5
this.startIndex = indexes xr/k.Fz
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[startIndex / pageSize]; $>UzXhf}\
} -Gpj^aBU
} Dk-L4FS
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publicint getNextIndex(){ r &[~/m8zl
int nextIndex = getStartIndex() + EyeLC6u
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pageSize; n`,Q:
if(nextIndex >= totalCount) GN<I|mGLJK
return getStartIndex(); {<2ZbN?
else |$t0cd
return nextIndex; =gIYa
} wj^I1;lO
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publicint getPreviousIndex(){ W24bO|>D
int previousIndex = getStartIndex() - rYJ))@
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pageSize; B`F82_O
if(previousIndex < 0) yjq
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return0; D'h2 DP!
else 6{
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return previousIndex; RtL<hD
} ^ztf:'l@C
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} o^?{j*)g
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抽象业务类
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java代码: @nP}q!y
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/** VO Qt{v{1|
* Created on 2005-7-12 deoM~r9s
*/ pqSE|3*l
package com.javaeye.common.business; 1,T9HpM
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import java.io.Serializable; l8-jFeeMd
import java.util.List; r!^\Q7
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import org.hibernate.Criteria; v+#j>
import org.hibernate.HibernateException; WDdi}i>2
import org.hibernate.Session; =!^iiHF
import org.hibernate.criterion.DetachedCriteria; wIF
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import org.hibernate.criterion.Projections; i =N\[&
import (J&Xo.<Z-
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org.springframework.orm.hibernate3.HibernateCallback; e<4z)
import -ZP&zOsDr
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org.springframework.orm.hibernate3.support.HibernateDaoS P|4E1O
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upport; CLEG'bZa,
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import com.javaeye.common.util.PaginationSupport; s jI[Vq
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public abstract class AbstractManager extends RYl3txw
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HibernateDaoSupport { q7&yb.<KD.
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privateboolean cacheQueries = false; m5w9l"U]H
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privateString queryCacheRegion; Czr4
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publicvoid setCacheQueries(boolean kA%OF*%|6
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cacheQueries){ BG:`Fq"T
this.cacheQueries = cacheQueries; +){a[@S@x
} 8TZA T%4
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publicvoid setQueryCacheRegion(String &8+6!TN7
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queryCacheRegion){ 3B".Gsm)X
this.queryCacheRegion = (4ci=*3=
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queryCacheRegion; 8[1DO1*P
} sN1*Zp'(
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publicvoid save(finalObject entity){ s.;KVy,=Bu
getHibernateTemplate().save(entity); G^rh*cb K
} qH%L"J
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publicvoid persist(finalObject entity){ {0vbC/?]
getHibernateTemplate().save(entity); V\K
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} ;D"P9b]9$
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publicvoid update(finalObject entity){ V87ee,
getHibernateTemplate().update(entity); y-<PsP-I
} ppwd-^f3j
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publicvoid delete(finalObject entity){ ]uBT &
getHibernateTemplate().delete(entity); Ux_EpC
} ;el]LnV!O
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publicObject load(finalClass entity, L]c 8d
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finalSerializable id){ T5K-gz7A
return getHibernateTemplate().load XoDJzrL#
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(entity, id); oS[W*\7'!
}
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publicObject get(finalClass entity, 2"T8^r|U
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finalSerializable id){ k)$iK2I
return getHibernateTemplate().get %3]3r*e&5
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(entity, id); \1=T
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} h=X7,2/<
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publicList findAll(finalClass entity){ '9^E8+=|
return getHibernateTemplate().find("from w0#%AK
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" + entity.getName()); bq:wEMM4s
} H"2 U)HJl
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publicList findByNamedQuery(finalString a^@+%?X
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namedQuery){ G!AICcP^
return getHibernateTemplate iYkRo>3!QX
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().findByNamedQuery(namedQuery); 8r2XGR
} 5kK=S
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publicList findByNamedQuery(finalString query, Us1@\|]
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finalObject parameter){ Sq?,C&LsA
return getHibernateTemplate .=?Sz*3
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().findByNamedQuery(query, parameter); H(MB5
} K3Huu!Tr
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publicList findByNamedQuery(finalString query, !>\9t9
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finalObject[] parameters){ t9ER;.e
return getHibernateTemplate "K8nxnq
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().findByNamedQuery(query, parameters); @v"T~6M
} Xe)Pg)J1
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publicList find(finalString query){ n:F@gZd`
return getHibernateTemplate().find 2%bhW,?I
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(query); 6!@0VI&P
} HP#ki !'
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publicList find(finalString query, finalObject A5+q^t}
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parameter){ 61G|?Aax
return getHibernateTemplate().find .hxin[Y
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(query, parameter); =<Hy"4+?.
} FWIih5 3`
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public PaginationSupport findPageByCriteria 4yhcK&
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(final DetachedCriteria detachedCriteria){ f;R>Pr;rD
return findPageByCriteria P>|Ef~j
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); W.IH#`-9E
} STw oYn
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public PaginationSupport findPageByCriteria )TM!ms+K
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(final DetachedCriteria detachedCriteria, finalint 5|5=Y/
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startIndex){ A3j"/eKi2
return findPageByCriteria f0OgK<.>T
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(detachedCriteria, PaginationSupport.PAGESIZE, S3QaYq"v
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startIndex); (,shiK[5f
} whw{dfE
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public PaginationSupport findPageByCriteria hw*1g m
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(final DetachedCriteria detachedCriteria, finalint @bE~@4mOu
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pageSize, 2!BsEvB(
finalint startIndex){ =88t*dH(,"
return(PaginationSupport) `wf|u M
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getHibernateTemplate().execute(new HibernateCallback(){ 9?$RO[vo
publicObject doInHibernate 'P,,<nkr|
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(Session session)throws HibernateException { 72u db^
Criteria criteria = K|Om5
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detachedCriteria.getExecutableCriteria(session); ^:+Rg}]W^
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount w1cw1xX*
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()).uniqueResult()).intValue(); >J>>\Y(p
criteria.setProjection -(
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(null); m!0N"AjA
List items = i_NJ -K
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criteria.setFirstResult(startIndex).setMaxResults puA|NT
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(pageSize).list(); |UYED%dC
PaginationSupport ps = oE6|Zw
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new PaginationSupport(items, totalCount, pageSize, 8ZW?|-i
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startIndex); CIEJql?`
return ps; W"|mpxp
} ODek%0=
}, true); mTJ"l(,3
} KxX[S.C
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public List findAllByCriteria(final bs
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DetachedCriteria detachedCriteria){ =q5@,wN^
return(List) getHibernateTemplate (_U^
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().execute(new HibernateCallback(){ 7=vYO|a/4
publicObject doInHibernate d@Q][7
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(Session session)throws HibernateException { >T QZk4$
Criteria criteria = ,z[(k"
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detachedCriteria.getExecutableCriteria(session); IkU|W3Vo
return criteria.list(); vf N#NY6
} .&PzkqWZ
}, true); I-bF{
} !LiQ 1`V{
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public int getCountByCriteria(final n]v7V&mj\
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DetachedCriteria detachedCriteria){ JjQVzkE
Integer count = (Integer) ;y OD
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getHibernateTemplate().execute(new HibernateCallback(){ `s%QeAde
publicObject doInHibernate vd(dNu&,<
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(Session session)throws HibernateException { [;FofuZ
Criteria criteria = O|7yP30?M
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detachedCriteria.getExecutableCriteria(session); H-2_j
return 9~~UM<66W
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criteria.setProjection(Projections.rowCount ul=7>";=|
: u-.T.zZl
()).uniqueResult(); ]F+K|X9-
} GI_DhU]~)
}, true); Ihqs%;V
return count.intValue(); ($SLb6
} 4.'JLArw
} <m]wi7
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用户在web层构造查询条件detachedCriteria,和可选的 1a8$f5
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ?ZX!7^7
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PaginationSupport的实例ps。 4|f}F
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ps.getItems()得到已分页好的结果集 D>Ua#<52q
ps.getIndexes()得到分页索引的数组 o"\{OX
ps.getTotalCount()得到总结果数 Bi
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ps.getStartIndex()当前分页索引 gZ*hkKN6
ps.getNextIndex()下一页索引 AygvJeM_W
ps.getPreviousIndex()上一页索引 "s${!A)
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4sI3(z)9H
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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 ynx WQ%d(`
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一下代码重构了。 6OMb`A@/2
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我把原本我的做法也提供出来供大家讨论吧: A>H*`{}
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首先,为了实现分页查询,我封装了一个Page类: U.d'a~pH
java代码: W<Bxm|
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/*Created on 2005-4-14*/ nLzX
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package org.flyware.util.page; k];L!Fj1
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/** XL&eJ
* @author Joa $j4?'-i=e
* <+1w'-
*/ g]#zWTw(
publicclass Page { WSB|-Qj}W
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/** imply if the page has previous page */ b>AAx$2Y
privateboolean hasPrePage; WZ
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/** imply if the page has next page */ %?G.lej,x
privateboolean hasNextPage; t T/*ZzMq#
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/** the number of every page */ rJ~(Xu>,s
privateint everyPage; = {DB
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/** the total page number */ pS)X\Xyw
privateint totalPage; q\pc2Lh?^
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/** the number of current page */ cXEy>U|/
privateint currentPage; ~~E=E;9
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/** the begin index of the records by the current ?*5l}y=
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query */ ?[fl$EG
privateint beginIndex; 7Sv5fLu2
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/** The default constructor */ W p*
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public Page(){ kK6>>lD'
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} Q-%=ZW Z
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/** construct the page by everyPage [eik<1=,~?
* @param everyPage wDTV /"Y
* */ }Nc!8'@
public Page(int everyPage){ !Yi<h/:
this.everyPage = everyPage; cmLu T/oV
} T:n^$RiT
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/** The whole constructor */ X)+sHcE~#
public Page(boolean hasPrePage, boolean hasNextPage, q&S.C9W
sbhEZ#7#
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int everyPage, int totalPage, Z- Ae'ym
int currentPage, int beginIndex){ ]h8V{%H
this.hasPrePage = hasPrePage; $1
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this.hasNextPage = hasNextPage; JEkVj']?
this.everyPage = everyPage; 4f~ZY]|nM
this.totalPage = totalPage; j[eEyCW[)
this.currentPage = currentPage; \ku{-^7
this.beginIndex = beginIndex; srA~gzF
} bW3o%srxa
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/** 3c6)
* @return "Jd1&FsCwX
* Returns the beginIndex. )ciHY6
*/ / /rWc,c
publicint getBeginIndex(){ ) O^08]Y g
return beginIndex; 1mM52q.R4
} &zy9} 4w,
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/** %QbrVl+
* @param beginIndex >D aS*r
* The beginIndex to set. b)@x@3"O
*/ \2b9A'd>
publicvoid setBeginIndex(int beginIndex){ L
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this.beginIndex = beginIndex; p}z0(lQ*~
} ITiw) M
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/** VG^-aR_F
* @return *k$&Hcr$
* Returns the currentPage. ZQ/5]]}3y
*/ 7 #N
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publicint getCurrentPage(){ Kwnu|8
return currentPage; S3fBZIPp
} >6q@Tr
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/** @gz?T;EC
* @param currentPage 7h~M&\M
* The currentPage to set. j!rz@Y3
*/ ^g\%VIOD
publicvoid setCurrentPage(int currentPage){ yvvR%]!.
this.currentPage = currentPage; @pz2}Hd|
} na)_8r~
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/** ?K"]XXsI
* @return _De;SB%V
* Returns the everyPage. =
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*/ T /uu='3
publicint getEveryPage(){ F(r&:3!97
return everyPage; u9Ro=#xt
} ^M"g5+q
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/** /~:ztv\$M"
* @param everyPage Kt(p|
* The everyPage to set. E
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*/ zFIbCv8
publicvoid setEveryPage(int everyPage){ .:}\Z27-c
this.everyPage = everyPage; CAO$Zt
} S{ !hpq~o
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/** 2Xosj(H
* @return Rk<:m+V=
* Returns the hasNextPage. u CXd%
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*/ [Pay<]c6g
publicboolean getHasNextPage(){ 4|qp&%9-
return hasNextPage; _"n4SXhq
} W+vm!7wX0
@Hzsud
/** ?d 4_'y
* @param hasNextPage ocvBKsfhE`
* The hasNextPage to set. HhO$`YZ%>
*/ =g ]C9'I3
publicvoid setHasNextPage(boolean hasNextPage){ BLRrHaX0
this.hasNextPage = hasNextPage; N{'k
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} q:(K^
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/** < mxUgU
* @return E_?
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* Returns the hasPrePage. shD$,!
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*/ Tb[GZ,/%;
publicboolean getHasPrePage(){ Z7 @#0;g{
return hasPrePage; 5HB4B <2
} S"dQ@r9
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/** !vU[V,~
* @param hasPrePage 8w\&QX
* The hasPrePage to set. ?h5Y^}8Qg
*/ ;J4_8N-
publicvoid setHasPrePage(boolean hasPrePage){ /a,q4tD@
this.hasPrePage = hasPrePage; E^rN)
} te`4*t
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/** @8 pRIS"V
* @return Returns the totalPage. }"szL=s
* v;OA hF r|
*/ $HaM,
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publicint getTotalPage(){ 4:K9FqU
return totalPage; }5A?WH_
} qU}[(9~Ru
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/** J9o]$.e
* @param totalPage #PiW\Tq
* The totalPage to set. (LnKaf8
*/ 8r~4iVwg
publicvoid setTotalPage(int totalPage){ 0;)4.*t
this.totalPage = totalPage; sVGyHA
} 9Y0w
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} Ty7xjIs
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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 |'.\}xt7
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个PageUtil,负责对Page对象进行构造: L\o-zNY
java代码: K;Fy&p^d
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/*Created on 2005-4-14*/ :W^
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package org.flyware.util.page; Y'0H2B8
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import org.apache.commons.logging.Log; ',~,hJ0
import org.apache.commons.logging.LogFactory; `C$.
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/** Rjt]^gb!*
* @author Joa lx(kbSxF
* x= X"4Mj0)
*/ @w?hXK=
publicclass PageUtil { )k$ +T%
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privatestaticfinal Log logger = LogFactory.getLog kocgPO5
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(PageUtil.class); f<?v.5($
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/** zb.dVK`7N-
* Use the origin page to create a new page fgdqp8~
* @param page g[4pG`z
* @param totalRecords Dn~c
* @return H[S[ y
*/ 5o2w)<d!
publicstatic Page createPage(Page page, int @~sJ
((G[5
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totalRecords){ Y`3V&8X
return createPage(page.getEveryPage(), =#0f4z
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page.getCurrentPage(), totalRecords); _Oc5g5_{
} bf@H(gCW=
y rH@:D/
/** kn%i#Fz
* the basic page utils not including exception eCFMWFhC
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handler 9lqH
* @param everyPage QNWGUg4*&
* @param currentPage |r['"6
* @param totalRecords FNlS)Bs
* @return page lWPh2k
*/ !:baG]Y
publicstatic Page createPage(int everyPage, int vj%3v4
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currentPage, int totalRecords){ 0#Ae<
everyPage = getEveryPage(everyPage); D| |)H
currentPage = getCurrentPage(currentPage); :_k5[KT.]9
int beginIndex = getBeginIndex(everyPage, 1Be/(pSc
T_)G 5a
currentPage); xB`j*
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int totalPage = getTotalPage(everyPage, q{Ao
j
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totalRecords); k:[T#/;
boolean hasNextPage = hasNextPage(currentPage, e1Q
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totalPage); mRO@ZY;5
boolean hasPrePage = hasPrePage(currentPage); ;W{2\ Es
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returnnew Page(hasPrePage, hasNextPage, ULH<FDot
everyPage, totalPage, d k/f_m
currentPage, G4rd<V0[D
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beginIndex); R =kXf/y
} R0~w F>
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privatestaticint getEveryPage(int everyPage){ w?V;ItcL
return everyPage == 0 ? 10 : everyPage; <
v1.+
} i^@hn>s$
`*WzHDv5p
privatestaticint getCurrentPage(int currentPage){ j-#h^3l1?
return currentPage == 0 ? 1 : currentPage; } `Cc-X7
} ~6=aoF5"3?
6<fcG
privatestaticint getBeginIndex(int everyPage, int 9zl-C*9vj
[gGo^^aW#
currentPage){ cHC1l
return(currentPage - 1) * everyPage; CC)Mws+2
} 3 S .2
%/2OP &1<
privatestaticint getTotalPage(int everyPage, int
RK/>5
ka@yQ V
totalRecords){ .oM;D~(=9
int totalPage = 0; [>LO'}%
@HE<\Z{ KI
if(totalRecords % everyPage == 0) Rrrq>{D
totalPage = totalRecords / everyPage; YpgO]\/w
else 87F]a3
totalPage = totalRecords / everyPage + 1 ; 5 qMP u|A
[e>2HIS,
return totalPage; [HhaBy9
} m2HO .ljc
BoXPX2:
privatestaticboolean hasPrePage(int currentPage){ ?rY+,nQP
return currentPage == 1 ? false : true; hcpe~spz9|
} GL _hRu
`YY07(%
privatestaticboolean hasNextPage(int currentPage, `_sKR,LhB
!$/P8T``M
int totalPage){ Gzp*Vr
return currentPage == totalPage || totalPage == 'Z|Czd8E
LVy`U07C V
0 ? false : true; i|0!yID0@
} y7,t"XV
{8 &=t8,c
!C(PfsrR/
} ixL[(*V
0KZ$v/m
G^Y^)pc]
:Dfl ,=S
C)~%(< D
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。 3sgo5D-rMI
vsPIvW!V
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 q;#bFPh
Y-,S_59
做法如下: hOYX
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 |"[;0)dw^
Ffd4c
的信息,和一个结果集List: Z{gDEo)
java代码: ?BbEQr
l3y}nh+ 8
@V&HE:P
/*Created on 2005-6-13*/ {suQ"iv
package com.adt.bo; WR u/7$8
Nrq/Pkmy
import java.util.List; b>9?gmR{
wv=U[:Y
import org.flyware.util.page.Page; (,|eE)+
+jS<n13T
/** %zR5q Lb
* @author Joa <dAxB$16sT
*/ Zad>iw}
publicclass Result { 8Pva ]Q
6W~JM^F
private Page page; k2.\1}\
.krEfY&
private List content; p@h<u!rL8
%$bhg&}
/** =$ T[
* The default constructor ?0-3J )kW
*/ ;iQw2XhT
public Result(){ Xc&J.Tw#4*
super(); wod(P73?
} YRv}w3yQ
zm_8{Rta}
/** eT?vZH[N
* The constructor using fields bZZ_yc
* ScQ9p379
* @param page iG"1~/U
* @param content n?S)H=
*/ :*R+ee,&-
public Result(Page page, List content){ G7KOJZb+D
this.page = page; I]cZcx,<q
this.content = content; uH7!)LE#
} 7#*`7 K'P!
P057]cAat<
/** FTzc,6
* @return Returns the content. %`s1
Ocvp
*/ !Q}Bz*Y
publicList getContent(){ 1_8@yO
return content; @y6^/'
} ?B`c<H"
kX*.BZI}C
/** HIvSh6|0p
* @return Returns the page. feM(
*/ Q91mCP~$
public Page getPage(){ 0Ag2zx
return page; tiRi_
} IK8"3+(
g3 !<A*<
/** [Kb)Q{=)
* @param content DweF8c
* The content to set. gQeoCBCE
*/ <W^>:!?w
public void setContent(List content){ Z}IuR|=
this.content = content; l=a<=i
} K]^Jl0
s-F3(mc(
/** R-2Abyts2
* @param page Wi*HLP!lNC
* The page to set. }{[p<pU$C
*/ (m')dSZ
publicvoid setPage(Page page){ Bi0&F1ZC!
this.page = page; Qe]&
} g}BS:#$
} "rrE_
^~3{n
" "CNw-^t
w-Q=oEt
B"t4{1/
2. 编写业务逻辑接口,并实现它(UserManager, K~qKr<)
A8ClkLC;I
UserManagerImpl) m'2EiYX$}\
java代码: Q.fD3g
{!pYQ|#
ei[, ug'
/*Created on 2005-7-15*/ ko~e*31_E
package com.adt.service; 9"dZ4{\!
bGik~
import net.sf.hibernate.HibernateException; %'9&JsO
C1-Jj_XQ.
import org.flyware.util.page.Page; f=>iiv
zKf0 :X
import com.adt.bo.Result; @[;$R@M_3
]w!=1(
/** )+a]M1j
* @author Joa .Txwp?};
*/ $-n_$jLY
publicinterface UserManager { %:Zp7O2UB'
Rts}y:44
public Result listUser(Page page)throws jG,^~5x
92^Dn`g
HibernateException; okBaQH2lUl
"I3&a1*
} /$UWTq/C7
J*qo3aJjE
9}11>X
q94*2@KV
.1[pO_
java代码: .X6V>e)(3
?xo<Fv
:;o?d&C
/*Created on 2005-7-15*/ t=dZM}wj_\
package com.adt.service.impl; n:%A4*
{G _|gs
import java.util.List; <}AmzeHr+
Q0TKM>
import net.sf.hibernate.HibernateException; iBqIV
o6S`7uwJ*/
import org.flyware.util.page.Page; QtfLJ5vi
import org.flyware.util.page.PageUtil; Q8bn|#`
[Mlmn$it
import com.adt.bo.Result; CdiL{zH\3
import com.adt.dao.UserDAO; P/8z
import com.adt.exception.ObjectNotFoundException; E>qe hs,g
import com.adt.service.UserManager; 4\2~wSr
A
Zv| |8p
/** /S%!{;:
* @author Joa yx/qp<=
*/ ]w9syz8X
publicclass UserManagerImpl implements UserManager { %l)~C%T
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private UserDAO userDAO; w7_2JS
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/** 5>M@
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* @param userDAO The userDAO to set. X[o"9O|<
*/ :,=Z)e
publicvoid setUserDAO(UserDAO userDAO){ "yxBD
7
this.userDAO = userDAO; u2Qs}FX
} ~8G cWy6
|-VbJd
/* (non-Javadoc) +@K8:}lOW
* @see com.adt.service.UserManager#listUser WFFpW{
Vq#_/23=$y
(org.flyware.util.page.Page) {,i='!WIm
*/ $6\W8v
public Result listUser(Page page)throws vghn+P8
DR#[\RzNI
HibernateException, ObjectNotFoundException { fT_swhIO
int totalRecords = userDAO.getUserCount(); 0B~Q.tyP
if(totalRecords == 0) `G.:G/b%H
throw new ObjectNotFoundException v4wXa:CJ
78<QNlKn
("userNotExist"); {1`n^j(>
page = PageUtil.createPage(page, totalRecords); (3Z~EIZz
List users = userDAO.getUserByPage(page); b1qli5
returnnew Result(page, users); nzORG
} Fgg4QF
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} {p@uj_pS
]6 {\`a
s
*1%I$=@
ZI#Xh5
jj 9eFB
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Nm/Fc
yw)Ztg)
询,接下来编写UserDAO的代码: !4G<&hvb
3. UserDAO 和 UserDAOImpl: L #l|}u
java代码: iP~dH/B|v
+,$"%C
F
/:2+
/*Created on 2005-7-15*/ g8_IZ(%:
package com.adt.dao; kpN'H_ .
p,w6D,h
import java.util.List; 3M&75OE
d\ Z#XzI8
import org.flyware.util.page.Page; "i_}\p.,X
".SQ*'Oc
import net.sf.hibernate.HibernateException; 4hv'OEl
~ Qt$)
/** LvNk:99:<
* @author Joa q}["Nww-
*/ ico(4KSk
publicinterface UserDAO extends BaseDAO { cNG6 A4
1xo<V5
publicList getUserByName(String name)throws AcF;5h
^MWfFpJV!]
HibernateException; ?%HtPm2< %
T<0Bq"'%
publicint getUserCount()throws HibernateException; G#! j`
<ZNa`
publicList getUserByPage(Page page)throws 2aN
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HibernateException; UmU=3et<Wj
;.h5; `&
} <u"#Jw/VP
\?fl%r2
WDiF:@^K
&w3LMOT
R#bg{|
java代码: $hO8
S =
<96ih$5D1
][bz5aV
/*Created on 2005-7-15*/ SJ7>*Sa(u$
package com.adt.dao.impl; 5|R2cc|"9
KCk?)Qv
import java.util.List; x
ctU.)p
Y(y9l{'
import org.flyware.util.page.Page; ;-?ZI$
"k-ov9yK
import net.sf.hibernate.HibernateException; %]ayW$4
import net.sf.hibernate.Query; d# 3tQ*G/
S/-7Zo&w+
import com.adt.dao.UserDAO; X[Ek'=}
v\Y}(fD
/** p??/r
* @author Joa }Hz-h4Z
*/ H\I!J@6g
public class UserDAOImpl extends BaseDAOHibernateImpl q.MVF]
b|dCEmFt
implements UserDAO { [S]!+YBK
g`OOVaB
/* (non-Javadoc) &^IcL!t[
* @see com.adt.dao.UserDAO#getUserByName z"K(
bw6
q{GSsDo-:V
(java.lang.String) p%"yBpSK
*/ ^v!im\ r
publicList getUserByName(String name)throws DvX3/z#T
~u0xXfv#
HibernateException { A,gx5!J
String querySentence = "FROM user in class }{8Fo4/
HB7(
com.adt.po.User WHERE user.name=:name"; -k&{nD|
Query query = getSession().createQuery m`$>:B
V+qJrZ,i
(querySentence); g6g$nY@Jm
query.setParameter("name", name); hoR=%pC*
return query.list(); 5ttMua <G?
} GzFE%< 9F
8*yo7q&
/* (non-Javadoc) NGD*ce"w
* @see com.adt.dao.UserDAO#getUserCount() s^>lOQ=
*/ zq;DIWPIoJ
publicint getUserCount()throws HibernateException {
gt_XAH
int count = 0; YN@6}B#1
String querySentence = "SELECT count(*) FROM h `ME(U~<<
\V^*44+
<!
user in class com.adt.po.User"; 7%9)C[6NSs
Query query = getSession().createQuery T|@#w%c''
r!$'!lCR
(querySentence); w,Z"W;|
count = ((Integer)query.iterate().next qWO]s=V!
vJRnBq+y
()).intValue(); #SQvXMT
return count; 1OJ*wI*
} efjO8J[uk-
0/\PZX+
/* (non-Javadoc) _1sMY hI
* @see com.adt.dao.UserDAO#getUserByPage wmo{YS3t|
i3Hz"Qs;
(org.flyware.util.page.Page) d/{Q
t
*/ (*,8KLV_i
publicList getUserByPage(Page page)throws X>8-`p
G02ox5X
HibernateException { u#`+[AC`
String querySentence = "FROM user in class 4'SaEsA~
'>3`rsu
com.adt.po.User"; 6b?`:$Cw3)
Query query = getSession().createQuery 5W+{U8\
k(P3LJcYQ
(querySentence); #{!O,`qD
query.setFirstResult(page.getBeginIndex()) XHxz @_rw
.setMaxResults(page.getEveryPage()); 1SW4Y
return query.list(); 2;G98H
} bV@7mmz:X+
Dg~
[#C-
} TPHYz>D]
q
IM
{h#6z>p"u2
&Yp+k}XU
A 4j<\xL
至此,一个完整的分页程序完成。前台的只需要调用 d.`&0
/D[dO6.
userManager.listUser(page)即可得到一个Page对象和结果集对象 GR%{T'ZD`
Z,WubX<
的综合体,而传入的参数page对象则可以由前台传入,如果用 gN?0m4[$i
#{x5L^v>]
webwork,甚至可以直接在配置文件中指定。 e*:}$u8a
JSgpb?(
下面给出一个webwork调用示例: (/K5! qh
java代码: [Ct=F|
Cxm6TO`-;
]>D)#
/*Created on 2005-6-17*/ QH~Jy*\+PX
package com.adt.action.user; R)+t]}
%c X"#+e
import java.util.List; T C8`JU=wV
L/?]^!.
import org.apache.commons.logging.Log; jWvtv ng
import org.apache.commons.logging.LogFactory; W"Q!|#;l.
import org.flyware.util.page.Page; =Vb~s+YW
tPU-1by$
import com.adt.bo.Result; =i>\2J%'R
import com.adt.service.UserService; x=]S.XI
import com.opensymphony.xwork.Action; S`iR9{+&
L-\ =J
/** s+,&|;Q
* @author Joa yNa;\UF
*/ } ptMjT{9
publicclass ListUser implementsAction{ B
+Aj*\Y.
8>N wCjN
privatestaticfinal Log logger = LogFactory.getLog 3;_
n{&
i#W*'
(ListUser.class); dz%EM8
$^_|j1z#i
private UserService userService; ?Elg?)os
nY_?Jq
private Page page; 30Drrno7Io
*(QH{!-$s
privateList users; *Zbuq8>
qX#MV>1
/* WeMAe
w/d
* (non-Javadoc) qZk:mlYd
* B,vOsa"x6`
* @see com.opensymphony.xwork.Action#execute() ".U^ifF
*/ 'bu )M1OLi
publicString execute()throwsException{ TDNf)Mm
Result result = userService.listUser(page); {0v*xL_O^
page = result.getPage(); vF4]ux&
users = result.getContent(); Tu m_aI
return SUCCESS; M \D]ml~
} 7J*N_8?2
jQh^WmN
/** Pbu{'y3J
* @return Returns the page. oPQtGl p
*/ @T-p2#&
public Page getPage(){ x/fX`y|(}*
return page; {~Tg7<\L
} Vb|#MNf)
'LE"#2Hu
/** NjuiD].
* @return Returns the users. 0s#Kp49-
*/ 3_$w|ET
publicList getUsers(){ C.Uju`3
return users; G}d-(X
} ]0V}D,V($
c=O,;lWFqm
/** z+{,WHjo
* @param page b7`D|7D
* The page to set. 7- d.ZG
*/ _qwQ;!9
publicvoid setPage(Page page){ .Pndx%X9s
this.page = page; )u%je~Vw
} )!bUR\
kOwMs<1J
/** =T?}Nt
* @param users 1T&Rc4$Sn7
* The users to set. rqPo)AL
*/ H`hnEOyLp
publicvoid setUsers(List users){ <W8t|jt
this.users = users;
uF|3/x=
} "I6P=]|b
*iO u'
/** zE T^T5>:
* @param userService Rd
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* The userService to set. 2jJmE&)7,
*/ f"G-
publicvoid setUserService(UserService userService){ !LMN[3M_
this.userService = userService; .T<=z
} PX:'/{V
} ia&AW
jd]s<C3o
+Mewo
wcSyw2D
\J. .*,'
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,
/-_=nf}w
zLs|tJOVp
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 _/8FRkx
9O`
m,t
么只需要: ^H{R+}
java代码: RpWTpT1
El_wdbbT
Hgeg@RP
Q
<?xml version="1.0"?> B[=(#W
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~CB[9D=
'w>_+jLT
1.0//EN" "http://www.opensymphony.com/xwork/xwork- YBYZ=,"d
E J$36
1.0.dtd"> HX'FYt/?t
S(S#
<xwork> yKYUsp
'1,,)U#6E
<package name="user" extends="webwork- \!(
vS\%3A4^+5
interceptors"> A+y
4S~o-`&W
<!-- The default interceptor stack name ,yd
MU\so(
&;H{cv`
--> ,$r2gr!_G
<default-interceptor-ref NnxM3*
kR.wOJ7'
name="myDefaultWebStack"/> rqCa 2
%IpSK 0<Sp
<action name="listUser" fUag1d
FYPz 4K
class="com.adt.action.user.ListUser"> {7Cx#Ewd
<param @kngI7=E
{j(4m
name="page.everyPage">10</param> FyD.>ot7M
<result /L)
9tt.
j.-VJo)
name="success">/user/user_list.jsp</result> O{KB0"s>i
</action> DM7}&~
sn k$^
</package> Oo%!>!Lt,
AvRcS]@=
</xwork> Ph7pd
9n}A ^
;?9A(q_Z
3\!F\tqD \
$"fo^?d/s
+}!DP~y+
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 qR,.W/eS8
xcSR{IZ
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 >7-y#SkXdo
SR*Gqx
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 QJ4AL3
^6
HY;oy(
6c\DJD
:zL 393(
hjY0w
我写的一个用于分页的类,用了泛型了,hoho j8HOc(
[%.18FWI
java代码: Gj6. Iv
!P|5#.eC
EODB`$+
package com.intokr.util; vj3isI4lU
*C_[jk@6
import java.util.List; 1)U}i ^
F!CAitxd
/** _om[VKJd
* 用于分页的类<br> w??c1)
* 可以用于传递查询的结果也可以用于传送查询的参数<br> nUqy1(
* x}"Q8kD
* @version 0.01 ]V<"(?,K
* @author cheng :o\5K2]:
*/ B
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public class Paginator<E> { Qq0O0U
privateint count = 0; // 总记录数 E/"SU*Co
privateint p = 1; // 页编号 ``-k{C#F
privateint num = 20; // 每页的记录数 ^g]xU1] *
privateList<E> results = null; // 结果 =x4a~=HX
9--dRTG
/** =h\E<dw
* 结果总数 A70(W{6a9@
*/ F50JJZ
publicint getCount(){ G^KC&
return count; {bTeAfbf]
} 0ny{)Sd6um
*tG11gR,&