Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9RY}m7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 u~27\oj,
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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 ,
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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 \p!mX|
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分页支持类: -)E6{
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java代码: y?V#LW[^E
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package com.javaeye.common.util; y-vBC3
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import java.util.List; !,;/JxfgVh
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publicclass PaginationSupport { }I#,o!)Vd
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publicfinalstaticint PAGESIZE = 30; Su[f"2oR
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privateint pageSize = PAGESIZE; 4:qM'z
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privateList items; 'U4@Sax,
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privateint totalCount; i>AKXJ+
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privateint[] indexes = newint[0]; r`d.Wy Zj
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privateint startIndex = 0; qeoj
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public PaginationSupport(List items, int GZNfx8zsY+
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totalCount){ FLOSdMYdw
setPageSize(PAGESIZE); |PW.CV0,
setTotalCount(totalCount); k[;(@e@c
setItems(items); sBWLgJz?C
setStartIndex(0); V?+Y[Q
} j{;IiVHnR
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public PaginationSupport(List items, int Km,:7#aV
9/R<,
totalCount, int startIndex){ @1G`d53N
setPageSize(PAGESIZE); rJ_fg$.<
setTotalCount(totalCount); O=wu0n
setItems(items); [[9XqD]
setStartIndex(startIndex); dnUiNs8
} 7Ys\=W1
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public PaginationSupport(List items, int s9}V nNr
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totalCount, int pageSize, int startIndex){ iWu^m+"k
setPageSize(pageSize); t(?tPt4zp
setTotalCount(totalCount); z2.Z xL"*
setItems(items); F
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setStartIndex(startIndex); f8?c[%br
} \hT=U*dMR
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publicList getItems(){ 4mJ[Wr\y
return items; -
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} ia}V8i
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publicvoid setItems(List items){ $f]dL};
this.items = items; l\{{iAC]I
} 8rA?X*|S!
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publicint getPageSize(){ @G;\gJT*
return pageSize; &lYe
} -THU5AB
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publicvoid setPageSize(int pageSize){ b];? tP
this.pageSize = pageSize; m6=Jp<
} JHZ`LWq
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publicint getTotalCount(){ %1oG<s
return totalCount; $"G=r(MW
} d;9F2,k$w
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publicvoid setTotalCount(int totalCount){ J|A:C[7 2
if(totalCount > 0){ RY]Vo8
this.totalCount = totalCount; 0ynvn9@t
int count = totalCount / XLNR%)l
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pageSize; N}tiaL4
if(totalCount % pageSize > 0) 9s}y*Vp
count++; ^7
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indexes = newint[count];
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for(int i = 0; i < count; i++){ UF ]g6u
indexes = pageSize * D7"RZF\)
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} <(U:v
}else{ .}.63T$h9
this.totalCount = 0; Z7t-{s64
} L93KsI
} }JKK"d}U
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publicint[] getIndexes(){ aA5rvP+
return indexes; h7h[!>
} \-?@
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publicvoid setIndexes(int[] indexes){ ^Q'^9M2)
this.indexes = indexes; 6GZzNhz
} (\=iKE4#
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publicint getStartIndex(){ ))qOsphN
return startIndex; 3:;2Av2(X.
} [N-t6Z*
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publicvoid setStartIndex(int startIndex){ C
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if(totalCount <= 0) </OZ,3J=
this.startIndex = 0; -8]M
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elseif(startIndex >= totalCount)
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this.startIndex = indexes LS=HX~5C
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[indexes.length - 1]; >,Zf3M
elseif(startIndex < 0) &!lGx7zf
this.startIndex = 0; nz=X/J6
else{ ~HH#aXh*
this.startIndex = indexes RU1+-
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[startIndex / pageSize]; 1qw*mV;W)_
} b@yGa%Gz@
} }BpCa6SAs
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publicint getNextIndex(){ R0n#FL^E
int nextIndex = getStartIndex() + w1je|Oil
-}B&>w,5
pageSize; kAEm#oz=g
if(nextIndex >= totalCount) Lwg@*:`d
return getStartIndex(); O+Zt*jN;
else pL{h1^O}
return nextIndex; ?~;8Y=O
} /idQfff
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publicint getPreviousIndex(){ <3wfY
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int previousIndex = getStartIndex() - eAkj pc
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pageSize; R(?g+:eCpM
if(previousIndex < 0) @c<*l+Qc
return0; &gn^i!%Z)
else Wgt[ACioN
return previousIndex; ;_.%S *W\
} #)aUKFX
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} qeK_w
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抽象业务类
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java代码: jXBAo
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/** ohFUy}y
* Created on 2005-7-12 IpX>G]"-C
*/ t,mD{ENm&
package com.javaeye.common.business; JsfX&dX0
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import java.io.Serializable; 87Sqs1>cw
import java.util.List; pg\Ylk"T
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import org.hibernate.Criteria; 0-ISOA&
import org.hibernate.HibernateException; Tl.dr
import org.hibernate.Session; [xF (t @p
import org.hibernate.criterion.DetachedCriteria; Y <'T;@
import org.hibernate.criterion.Projections; ^:.=S`,^
import f?_UT}n
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org.springframework.orm.hibernate3.HibernateCallback; ^f:oKKaAW;
import YQyf:xJ
_b+=q:$/
org.springframework.orm.hibernate3.support.HibernateDaoS n+db#qAj5
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upport; vJ__jO"Sq
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import com.javaeye.common.util.PaginationSupport; ?mdgY1
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public abstract class AbstractManager extends Zrtyai{8l
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HibernateDaoSupport { F;5S2:a@Z
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privateboolean cacheQueries = false; t(-`==.R
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privateString queryCacheRegion; >z'kCv
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publicvoid setCacheQueries(boolean VKcO]_W1
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cacheQueries){ EV}c,*);y
this.cacheQueries = cacheQueries; 3snr-)
} o`hVI*D
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publicvoid setQueryCacheRegion(String ?lg
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queryCacheRegion){ $q_e~+SXT
this.queryCacheRegion = 1'c
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queryCacheRegion; ZJCD)?]=3
} V87?J w%2
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publicvoid save(finalObject entity){ vs3px1Xe#
getHibernateTemplate().save(entity); tDF=Iqu)a
} 6%/@b`vZ
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publicvoid persist(finalObject entity){ o"5Bg%H
getHibernateTemplate().save(entity); iNn]~L1
} %#!pAUP\&
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publicvoid update(finalObject entity){ Q~R7 ]AyR
getHibernateTemplate().update(entity); RrM C[2=
} Lq#>N_72W0
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publicvoid delete(finalObject entity){ k 7 !{p
getHibernateTemplate().delete(entity); ';g]!XsY)
} Y7QIFY's~
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publicObject load(finalClass entity, +}IOTw"O`
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finalSerializable id){ a<-'4D/
return getHibernateTemplate().load >EQd;Af
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(entity, id); W0vdU;?%
} H{Zfbb
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publicObject get(finalClass entity, &&Sl0(6x[T
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finalSerializable id){ EZ+_*_9
return getHibernateTemplate().get 2rS|V|d
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(entity, id); *],]E;
} 7x
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; Drt4fOxX
publicList findAll(finalClass entity){ "xS?#^a
return getHibernateTemplate().find("from ifA{E}fRZP
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" + entity.getName()); F-MN%WD~
} P{
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publicList findByNamedQuery(finalString 0QE2e'}}-
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namedQuery){ :b^\O
return getHibernateTemplate &%QtUPvr9
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().findByNamedQuery(namedQuery); <^}{sdOyu
} 16q"A$
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publicList findByNamedQuery(finalString query, S^}@X?v
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finalObject parameter){ cwK6$Ax
return getHibernateTemplate h(aF>a\Z
p #:.,;
().findByNamedQuery(query, parameter); l@-J&qG
} s_} 1J,Y
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publicList findByNamedQuery(finalString query, u_.`I8qa
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finalObject[] parameters){ !|P>%bi
return getHibernateTemplate $E;`Y|r%WK
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().findByNamedQuery(query, parameters); $j(2M?.>#
} >mzK96
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publicList find(finalString query){ Z/=x(I0
return getHibernateTemplate().find k8E'wN
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(query); RFyeA.
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} 't3/< h<
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publicList find(finalString query, finalObject !@E=\Sm8EV
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parameter){ fDo )~t*~
return getHibernateTemplate().find D.G+*h@ g
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(query, parameter); M~Tq'>Fn
} ]wLHe2bEu
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public PaginationSupport findPageByCriteria !$ikH,Bh
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(final DetachedCriteria detachedCriteria){ hz8Y2Ew
return findPageByCriteria ol^J-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Y=JfV
} SEm3T4dfzf
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public PaginationSupport findPageByCriteria aNgaV$|2a
;' !G?)PZ
(final DetachedCriteria detachedCriteria, finalint wPTXRq%
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startIndex){ ES72yh]
return findPageByCriteria mXnl-_
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(detachedCriteria, PaginationSupport.PAGESIZE, |<&9_Aq_
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startIndex); 3 A2X1V"
} [pf78
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public PaginationSupport findPageByCriteria VYj hU?I
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(final DetachedCriteria detachedCriteria, finalint F)KUup)gc
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pageSize, g+h)s!$sB
finalint startIndex){ 1wpT"5B
return(PaginationSupport) uxF88$=!t
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getHibernateTemplate().execute(new HibernateCallback(){ _y{z%-
publicObject doInHibernate )`?Es8uW
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(Session session)throws HibernateException { E,,)?^ g
Criteria criteria = %(h-cuhq
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detachedCriteria.getExecutableCriteria(session); K@lZuQ.1
int totalCount = "HTp1
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((Integer) criteria.setProjection(Projections.rowCount sev^
7g1"s1~or
()).uniqueResult()).intValue(); 4G;FpWQm
criteria.setProjection 46c7f*1l
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(null); |5|^[v
List items = WoGK05w
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criteria.setFirstResult(startIndex).setMaxResults Srw ciF
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(pageSize).list(); \ZiZX$
PaginationSupport ps = e6n1/TtqM
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s
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new PaginationSupport(items, totalCount, pageSize, -#srn1A>
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startIndex); MkJ}dncg*
return ps; Ek\fx*Lz
} MJ^NRT0?b
}, true); O8#}2
} .`4N#EjP
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public List findAllByCriteria(final \5UwZx\
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DetachedCriteria detachedCriteria){ udxLHs
return(List) getHibernateTemplate ZzfGs
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().execute(new HibernateCallback(){ BEM_y:#
publicObject doInHibernate IxC/X5Mp^q
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(Session session)throws HibernateException { <4s$$Uw}6%
Criteria criteria = 5fi6>>
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detachedCriteria.getExecutableCriteria(session); Sqj'2<~W
return criteria.list(); envu}4wU=e
} o_
}, true); J0xOB;rd
} O[[:3!6q
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public int getCountByCriteria(final AkdONKO8{
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DetachedCriteria detachedCriteria){ l<
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Integer count = (Integer) Ys,}L.
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getHibernateTemplate().execute(new HibernateCallback(){ 'T@K$xL8
publicObject doInHibernate Omo1p(y
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(Session session)throws HibernateException { zp[Uh]-dMK
Criteria criteria = X~XpX7d!
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detachedCriteria.getExecutableCriteria(session); +jD?h-]
return !`S?
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criteria.setProjection(Projections.rowCount *IWO ,!
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()).uniqueResult(); u
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} @f442@_4
}, true); "o&_tB;O
return count.intValue(); ZY-UQ4_|u
}
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} A `\2]t$z
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用户在web层构造查询条件detachedCriteria,和可选的 Q#NXJvI
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 UO^"<0u
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PaginationSupport的实例ps。 TR3_!0
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ps.getItems()得到已分页好的结果集 )70-q yA
ps.getIndexes()得到分页索引的数组 Cv{>|g#
ps.getTotalCount()得到总结果数 |&Gm.[IX;q
ps.getStartIndex()当前分页索引 s.z (1MB]
ps.getNextIndex()下一页索引 --E_s/
ps.getPreviousIndex()上一页索引 ~oO>6
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 nDx}6}5)
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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'(yrz!
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一下代码重构了。 [5Zs%!Z;8N
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我把原本我的做法也提供出来供大家讨论吧: 0~{jgN~
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首先,为了实现分页查询,我封装了一个Page类: M:V'vme)+
java代码: @{16j#'R
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/*Created on 2005-4-14*/ F|\^O[#R
package org.flyware.util.page; x*GGO)r
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/** KS%LX c('
* @author Joa iX4?5yz~<
* 4DaLt&1
*/ n$B SO
publicclass Page { ';"W 0
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/** imply if the page has previous page */ ,r\
privateboolean hasPrePage; +\~.cP7[
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/** imply if the page has next page */ 9m^"ca
privateboolean hasNextPage; ktX\{g! U
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/** the number of every page */ Gs^hqT;h
privateint everyPage; Wj0=cIb
n[$b k_S
/** the total page number */ |HhqWja
privateint totalPage; A.nU8
c*LB=;npI
/** the number of current page */ f5p>oXo4b
privateint currentPage; Pi|WOE2
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/** the begin index of the records by the current C+\c(M a
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query */ =.197)e
privateint beginIndex; H+Dv-*i
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/** The default constructor */ nT.i|(xd.
public Page(){ ^Pqj*k+F
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} jI})\5<R
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/** construct the page by everyPage hKa<9>MI`
* @param everyPage kY d'6+m
* */ fyYHwG
public Page(int everyPage){ \@IEqm6
this.everyPage = everyPage; XL9smFq
} @Z9X^Y+u^h
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/** The whole constructor */ MR$R#
public Page(boolean hasPrePage, boolean hasNextPage, G i1Jl"
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int everyPage, int totalPage, (C{l4
int currentPage, int beginIndex){ .!#0eAT
this.hasPrePage = hasPrePage; nymF`0HYe1
this.hasNextPage = hasNextPage; $7k"?M_
this.everyPage = everyPage; -!_f-Nny
this.totalPage = totalPage; qfJi[8".
this.currentPage = currentPage; ./SDZ:5/
this.beginIndex = beginIndex; Ht >5R
} KO*# ^+g
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/** 5q<cZ)v#&
* @return NXwthc3
* Returns the beginIndex. \YXzq<7
*/ tOUpK20q.@
publicint getBeginIndex(){ i_/A,5TF
return beginIndex; mab921-n
} S5o\joc
1!N|a< #
/** 7 'T3Wc
* @param beginIndex (i..7B:
* The beginIndex to set. ylFoYROO
*/ \gz(C`4{j
publicvoid setBeginIndex(int beginIndex){ ..FEyf
this.beginIndex = beginIndex; $7J9Yzp?L
} 2HA-q),6
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/** rlUo#
* @return `<Ry_}V
* Returns the currentPage. ^,-2";2Xh
*/ ,"6Bw|s
publicint getCurrentPage(){ Oy(fh%k#
return currentPage; .DX
} !{u`}:\
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/** \mK;BWg)
* @param currentPage * A<vrkHz
* The currentPage to set. <'y}y}%
*/ V{A_\
publicvoid setCurrentPage(int currentPage){ 0^lCZ,uq;
this.currentPage = currentPage; B3AWJ1o
} '{>R-}o[3
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/** (5rfeSA^
* @return r`dQ<U,
* Returns the everyPage. =1MVF
*/ nYFM^56>_
publicint getEveryPage(){ `jHbA #sO
return everyPage; QUQw/
} Am'%tw
~
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/** `[)!4Jb
* @param everyPage _^%DfMP3i\
* The everyPage to set. -- >q=hlA
*/ U ;%cp
publicvoid setEveryPage(int everyPage){ F<V.OFt
this.everyPage = everyPage; 2gasH11M
} cFD3
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/** <%Al(Lm0
* @return !"d"3coQ?
* Returns the hasNextPage. i)!2DXn
*/ z=FOymvC
publicboolean getHasNextPage(){ mb\"qD5
return hasNextPage; Svicw`uX0
} -~_[2u^3
y2`},
/** .QvH7
* @param hasNextPage @S<6#zR
* The hasNextPage to set. uh<e-;vU
*/ z7X,5[P
publicvoid setHasNextPage(boolean hasNextPage){ m7#v2:OD+
this.hasNextPage = hasNextPage; e,K.bgi
} d1qvS@
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/** ,J&\)
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* @return fxQ4kiI
* Returns the hasPrePage. Q"vhl2RX
*/ I/B *iW^
publicboolean getHasPrePage(){ _
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return hasPrePage;
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} <B&vfKO^h
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/** ~ K/_51O'
* @param hasPrePage J?9n4
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* The hasPrePage to set. (Q?@LzCjy
*/ y*#YIS56I
publicvoid setHasPrePage(boolean hasPrePage){ 7 1+
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this.hasPrePage = hasPrePage; |!q,J
} elGwS\sw
wg UgNwd1
/** kNd(KQ<.17
* @return Returns the totalPage. ^wIg|Gc
* i5 0c N<o
*/ *S<d`mp[
publicint getTotalPage(){ ZLZh$eZZ
return totalPage; LgxsO:mi
} hiKyU!)Hv
(fun,(R6"
/** 6Z l#$>P
* @param totalPage wnU-5r&!]
* The totalPage to set. ZOBcV,K
*/ ipe8U1Sc
publicvoid setTotalPage(int totalPage){ Ya
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this.totalPage = totalPage;
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} 6r.#/' "
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} XI+GWNAmJ
6z5wFzJv?q
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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 qi*Dd[OG
&n'@L9v81
个PageUtil,负责对Page对象进行构造: Ih HKRb[
java代码: RT.
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/*Created on 2005-4-14*/ ZmDM=qN
package org.flyware.util.page; D(WdI
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import org.apache.commons.logging.Log; N9#5 P!
import org.apache.commons.logging.LogFactory; J9/EJ'My
Urz9S3#\
/** < V*/1{
* @author Joa `x`zv1U
* .lAPlJOO
*/ ;efF]")
publicclass PageUtil { xpJ=yxO
m
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privatestaticfinal Log logger = LogFactory.getLog H]}mg='kI
mX%T"_^
(PageUtil.class); pr[V*C/
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/** QM'|k6
* Use the origin page to create a new page \fsNI T/
* @param page rvacCwI
* @param totalRecords P(UY}oU
* @return +G6 Ge;
*/ 0a2#36;_IK
publicstatic Page createPage(Page page, int j 8)*'T
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totalRecords){ Zu*7t<W
return createPage(page.getEveryPage(), dT{GB!jz
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page.getCurrentPage(), totalRecords); ~d3|zlh
} cw,|,uXq
6
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/** 0RjFa;j
* the basic page utils not including exception o!lKP>
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handler v|KGzQx$.*
* @param everyPage nvCp-Z$
* @param currentPage }5;/!P_A
* @param totalRecords &;bey4_J
* @return page ,9M2'6=
*/ :Q,~Nw>
publicstatic Page createPage(int everyPage, int @?jbah#
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currentPage, int totalRecords){ vJ{F)0 K
everyPage = getEveryPage(everyPage); Y4+]5;B8
currentPage = getCurrentPage(currentPage); W!"Oho'
int beginIndex = getBeginIndex(everyPage, 1gnLKf c
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currentPage); dlA0&;}z
int totalPage = getTotalPage(everyPage, WL|<xNL
_f~$iY
totalRecords); e=s({V
boolean hasNextPage = hasNextPage(currentPage, },{sJ0To
1\%@oD_zG
totalPage); +s6v!({Z
boolean hasPrePage = hasPrePage(currentPage); Vry*=X&Q
2r!- zEV
returnnew Page(hasPrePage, hasNextPage, qnb/zr)p
everyPage, totalPage, hE
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currentPage, oJ tmd}
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beginIndex); CED[\n
} 1>/ iYf
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privatestaticint getEveryPage(int everyPage){
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return everyPage == 0 ? 10 : everyPage; E`.:V<KW/
} K"[\)&WBG
+tlBOl$
privatestaticint getCurrentPage(int currentPage){ Ljiw9*ZI
return currentPage == 0 ? 1 : currentPage; >xA(*7
} ?LJiFG]^m
x+TdTe;p
privatestaticint getBeginIndex(int everyPage, int da~_(giD*
G^cMY$?99
currentPage){ /;TtMQt
return(currentPage - 1) * everyPage; cNikLd~?A
} >5E1y!
;W|GUmADf
privatestaticint getTotalPage(int everyPage, int #?`S+YN!q)
_#Lq~02 %
totalRecords){ @FZ_[CYg
int totalPage = 0; N`{6<Z0
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if(totalRecords % everyPage == 0) Vc6
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totalPage = totalRecords / everyPage; fq4uiFi<
else NcHU)
totalPage = totalRecords / everyPage + 1 ; ao0^;
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return totalPage; ;at1|E*
} obN8+ j
Wsp c;]&
privatestaticboolean hasPrePage(int currentPage){ x}O,xquY
return currentPage == 1 ? false : true; R+t]]n6#
} `mI5Z*]-
8GRB6-.h
privatestaticboolean hasNextPage(int currentPage, K'/if5>Bc
+J~%z*A
int totalPage){ tSnsjd<6.
return currentPage == totalPage || totalPage == y(/5l
=c$x xEDD
0 ? false : true; 0~+*$W
} B'mUDW8\D
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} 6tjV^sjs
}#;.b'`
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p] N/]2rR
@h_ bXo
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ,`OQAJ)>
4;>HBCM4-
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 oX*;iS X
lWd@
做法如下: ,jtaTG.>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 +Wgfxk'{
\YFM5l;IU
的信息,和一个结果集List: OHW|?hI=[
java代码: @ULWVS#t2
r&Qa;-4Pl
#d<|_
/*Created on 2005-6-13*/ |H]0pbC)w
package com.adt.bo; 1G67#L)USq
#0Uz1[
import java.util.List; o2hk!#5[4
[c lwmx
import org.flyware.util.page.Page; A|]#b?-
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/** @/ nGc9h
* @author Joa : 2$*'{mM
*/ 9[W >`JKo
publicclass Result { e ky1}
$TS97'$
private Page page; [Y?Y@x"MZ
QSn18V>{
private List content; x]`@%8Sm
#D%6b
/** Qca3{|r`
* The default constructor "nb.!OG~(
*/ ~R~.D
public Result(){ ~)`\j
super(); @$ju Qm
} ].5q,A]
*9w-eK1{
/** r{84Y!k~*
* The constructor using fields q_ryW$/_
* $uJc/
* @param page $duT'G, -
* @param content .Pte}pM"v
*/ 6w(r}yO]
public Result(Page page, List content){ En#Q
p3
this.page = page; _d!o,=}
this.content = content; $-~"G,;F
} ,nCvA%B!
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/** h^qZi@L
* @return Returns the content. F
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*/ b62B|0i
publicList getContent(){ Ctn?O~u
return content; &l!T2PX!
} Iu~<Y(8^q#
5o>*a>27,A
/** vF pKkS343
* @return Returns the page. 7jQVm{{.
*/ #qR 6TM&;
public Page getPage(){ 5XzsqeG|
return page; A+frKoi
} ZZHzC+O#^
Iz'Et'w8!
/** q8-hbWNm4
* @param content X9SOcg3a
* The content to set. DpQWh+WRy
*/ O^ui+44wp
public void setContent(List content){ Xdl
dUK[
this.content = content; 6>;OVX
} Rg\4#9S JF
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/** )8eb(!}7
* @param page @Tq-3Um
* The page to set. guGX
G+
*/ GoAh{=s
publicvoid setPage(Page page){ (xWsyo(4
this.page = page; b SgbvnJ
} ~k?wnw
} `Mbs6AJ
($/l_F
sQ^t8Y9
s :BW}PM
%G,7Ul1f
2. 编写业务逻辑接口,并实现它(UserManager, :) -`
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UserManagerImpl) j}s/)}n|
java代码: H_t0$x(\
;Ss!OFK
TU2oQ1
/*Created on 2005-7-15*/ -sZ'<(3
package com.adt.service; $F9w0kz:,*
}o7- 3!{L!
import net.sf.hibernate.HibernateException; +>;Ux1'@
rPyjr(I"_
import org.flyware.util.page.Page; WLwi
r79P|)\
import com.adt.bo.Result; i>[xN[U(
%t!r
pyD
/** WAR!#E#J7
* @author Joa mAGD qz>f
*/ lo'#dpt<
publicinterface UserManager { Mp!1xx
aXQAm$/
>
public Result listUser(Page page)throws '0)`.
3)LS#=
HibernateException; a9.255
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} f(eXny@Y
';8 ,RTe
5S!j$_(
:p@jslD
#>\SK
java代码: RU'a8j+W
S{8-XiL,
<ta{)}IN^
/*Created on 2005-7-15*/ +v5f-CBu
package com.adt.service.impl; skan1wQ
RMpiwO^
import java.util.List; :<{15:1
qxAh8RR;/
import net.sf.hibernate.HibernateException; *{k{
IDw`k[k
import org.flyware.util.page.Page; z"\w9 @W
import org.flyware.util.page.PageUtil; ^c(r4#}$"
Pi |Z\j)
import com.adt.bo.Result; ?u:mscb
import com.adt.dao.UserDAO; HWB\}jcA6u
import com.adt.exception.ObjectNotFoundException; !jU{ }RCR
import com.adt.service.UserManager; "(p /3qFY
7 kA+F+f
/** ~vA8I#.
* @author Joa KU{zzn;g
*/ sb3z8:r
publicclass UserManagerImpl implements UserManager { `MCtm(<
,X:3w3nr^
private UserDAO userDAO; x7^VU5w#
517wduj
/** r#1W$~?>
* @param userDAO The userDAO to set. X(Mpg[,N"
*/ .o]I^3tfc
publicvoid setUserDAO(UserDAO userDAO){ "M/) LXn:0
this.userDAO = userDAO; Q(aNa!
} u$zRm(!RB
$M0l
(htR
/* (non-Javadoc) y4|<+9<7
* @see com.adt.service.UserManager#listUser ^'tT_
gT
?SO!INJ
(org.flyware.util.page.Page) zh=0zJ
*/ @6+_0^
public Result listUser(Page page)throws dqQJC qc!
8d8jUPFQ
HibernateException, ObjectNotFoundException { _=`DzudE
int totalRecords = userDAO.getUserCount(); W.cc!8
if(totalRecords == 0) $8 &Y(`
throw new ObjectNotFoundException )6X-m9.X
WjR2:kT
("userNotExist"); TB&IB:4)R
page = PageUtil.createPage(page, totalRecords); lDKyD`WKnZ
List users = userDAO.getUserByPage(page); E
$\nb]JQ
returnnew Result(page, users); %O#zE-H"
} L>g6
9D!
X)Tyxppf'
} +e*C`uP!
dyf>T}Iy
FW;}S9u3
-:'%YHxX
NT5##XOB
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 hWFOed4C
|@1(^GX
询,接下来编写UserDAO的代码: 0g=vMLi
3. UserDAO 和 UserDAOImpl: 3WwCo.q;m
java代码: us1$
<"`f!k#[
Ci4c8
/*Created on 2005-7-15*/ J@<f*
package com.adt.dao; %(6+{'j~#
W)]&G}U<
import java.util.List; p$x>I3C(\
I8T*_u^_
import org.flyware.util.page.Page; Ah@e9`_r
[Y.JC'F#
import net.sf.hibernate.HibernateException; T]1.":
)=#Js<&3:
/** a=y%+E'a'
* @author Joa X@Zt4)2#
*/ eNi#% ?=WB
publicinterface UserDAO extends BaseDAO { Q<MxbHk9
"M2WK6?O5
publicList getUserByName(String name)throws #?D[WTV
qBK68B)
HibernateException; 2G5|J{4w
=N\$$3m?
publicint getUserCount()throws HibernateException; HN/YuP03[
NYg&