Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 bNc=}^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 qU=$ 0M
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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 S{
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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 iLS'47
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分页支持类: ii~~xt1
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java代码: {){i
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package com.javaeye.common.util; }hl#
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import java.util.List; ]LP&v3
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publicclass PaginationSupport { rGq~e|.O3
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publicfinalstaticint PAGESIZE = 30; 0!!pNK%(
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privateint pageSize = PAGESIZE; 8 Z#)Xb4
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privateList items; .!=g
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privateint totalCount; Ym!Ia&n
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privateint[] indexes = newint[0]; nc l-VN
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privateint startIndex = 0; ~W`upx)j
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public PaginationSupport(List items, int 4Jo:^JV
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totalCount){ 9~>;sjJk
setPageSize(PAGESIZE); S
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setTotalCount(totalCount); 4$vya+mAk5
setItems(items); L!/USh:IP
setStartIndex(0); qW7S<ouh
} @gs
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public PaginationSupport(List items, int zf2]|]*xz
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totalCount, int startIndex){ a"hlPJlG
setPageSize(PAGESIZE); WO_cT26Y
setTotalCount(totalCount); &a-:ZA@
setItems(items); 6)DYQ^4y
setStartIndex(startIndex); c< \:lhl
} I_eYTy-a`1
b/ur!2yr
public PaginationSupport(List items, int P3@[x
OGh bH a
totalCount, int pageSize, int startIndex){ v>0xHQD*<M
setPageSize(pageSize); TX8,+s+
setTotalCount(totalCount); @\[&_DZ
setItems(items); gxL5%:@
setStartIndex(startIndex); HiVF<tN
} |\Qr
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publicList getItems(){ g^8bY=*
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return items; '&s:,o-p
} Vk>aU3\c
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publicvoid setItems(List items){ rWSw1(sAA
this.items = items; VU)ywIs
} >#c]rk:
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publicint getPageSize(){ xae}8E
return pageSize; RI cA)I.
} zneK)C8&q3
P1H`NOC
publicvoid setPageSize(int pageSize){ 1>l{c
this.pageSize = pageSize; oREZ^pE@
} O^oFH
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publicint getTotalCount(){ &*L:4By)]
return totalCount; #p*OLQ3~
} hIPDJ1a
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publicvoid setTotalCount(int totalCount){ t~X wF(";
if(totalCount > 0){ a<c % Xy/
this.totalCount = totalCount; `^(6{p ?
int count = totalCount / UHweV:(|T
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pageSize; Y@RPQPmIQ
if(totalCount % pageSize > 0) +Bc/@.Q'
count++; =s1"<hH}O)
indexes = newint[count]; $5cLhi"`
for(int i = 0; i < count; i++){ }q27M
indexes = pageSize * 0>Ecm#
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i; Alh%Z\
} 3vmLftZE}
}else{ $ShL^g@
this.totalCount = 0; -\AB!#fh
} S1 %{/w
} (a]'}c$X9`
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publicint[] getIndexes(){ luLm:NWUM
return indexes; \wO)w@"
} 8R8J./i.K
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publicvoid setIndexes(int[] indexes){ ZK3?"|vhC
this.indexes = indexes; ~"brfjd|
} hSr#/d w&
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publicint getStartIndex(){ f{WJM>$:
return startIndex; <}N0y*m
} '-gk))u>)
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publicvoid setStartIndex(int startIndex){ Og"50 -
if(totalCount <= 0) ObMsncn
this.startIndex = 0; 1wqCoDgkp
elseif(startIndex >= totalCount) fy9{W @E3p
this.startIndex = indexes *sB=Ys?
qV8;;&8r
[indexes.length - 1]; eJ$?T7aUf
elseif(startIndex < 0) z15(8Y@2]
this.startIndex = 0; $9Y2\'w<h6
else{ ANn{*h
this.startIndex = indexes 7^as~5'&-
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[startIndex / pageSize]; GAtK1%nPD
} :#c? `>uV
} SM![ yC
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publicint getNextIndex(){ 1H-R-NNJ:
int nextIndex = getStartIndex() + RYS]b[-xZz
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pageSize; 9v0.]
if(nextIndex >= totalCount) =5I1[p;
return getStartIndex(); 6DR@$fpt
else _(J- MCY\
return nextIndex; Pw
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} R 5bt~U
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publicint getPreviousIndex(){ [WX+/pm7>
int previousIndex = getStartIndex() - X1#D}
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pageSize; U7tT
if(previousIndex < 0) w&`gx6?-na
return0; q;tsA"l
else Mwp#.du(
return previousIndex; xgsD<3
} bq<QUw=]q&
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} v#YO3nD
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抽象业务类 :[|`&_D9J
java代码: ^?&Jq_oU
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/** qJ#?=ITE
* Created on 2005-7-12 g4RkkoZ>)
*/ |3Oe2qb
package com.javaeye.common.business; QVn!60[lj
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import java.io.Serializable; eV1O#FLbi
import java.util.List; H :d{Sru
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import org.hibernate.Criteria; `H+ 7Hj
import org.hibernate.HibernateException; g%1!YvS3v
import org.hibernate.Session; ,^:Zf|V
import org.hibernate.criterion.DetachedCriteria; Xdq2 .:\
import org.hibernate.criterion.Projections; T1\Xz-1
import }_@cqx:n^
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org.springframework.orm.hibernate3.HibernateCallback; #}:VZ2Z
import _
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org.springframework.orm.hibernate3.support.HibernateDaoS Wy)|-Q7
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upport; |>jlY|
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import com.javaeye.common.util.PaginationSupport; 92+({ fgW
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public abstract class AbstractManager extends E
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HibernateDaoSupport { V1xpJ
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privateboolean cacheQueries = false; `:i|y
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privateString queryCacheRegion; mrE^D|
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publicvoid setCacheQueries(boolean b;9v.MZ4>g
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cacheQueries){ <kPU*P,
this.cacheQueries = cacheQueries; `^wF]R
} j05ahquI
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publicvoid setQueryCacheRegion(String hKt
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queryCacheRegion){ L4
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this.queryCacheRegion = /uW6P3M
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queryCacheRegion; 1PjSa4
} zu*0uL
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publicvoid save(finalObject entity){ Fl(+c0|kT
getHibernateTemplate().save(entity); (.<Gde#
} X~]eQaJ
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publicvoid persist(finalObject entity){ 84e)huAs
getHibernateTemplate().save(entity); u;h9Ra1
} =Ky1v$<
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publicvoid update(finalObject entity){ !COaPrg
getHibernateTemplate().update(entity); ZKAIG=l&!
} q fadsVp
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publicvoid delete(finalObject entity){ i.0}qS?
getHibernateTemplate().delete(entity); i*9eU*i|H
} Ds&)0Iwf
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publicObject load(finalClass entity, pFGdm3pV
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finalSerializable id){ ib/&8)Y+J
return getHibernateTemplate().load 5p
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(entity, id); wvx
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} e_\4(4x
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publicObject get(finalClass entity, GB^Ch YOb
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finalSerializable id){ 7I(Sa?D:
return getHibernateTemplate().get m#grtmyMrI
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(entity, id); S%mN6b~{
} +]`MdOu
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publicList findAll(finalClass entity){ 7EQ
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return getHibernateTemplate().find("from (+CB)nV0IA
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" + entity.getName()); )nQpO"+M
} hh
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publicList findByNamedQuery(finalString A}H)ojG'v
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namedQuery){ Z^>3}\_v
return getHibernateTemplate 8'Z9Z*^h#x
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().findByNamedQuery(namedQuery);
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} VSms hld
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publicList findByNamedQuery(finalString query, -Ww'wH'2
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finalObject parameter){ E-.M+[
return getHibernateTemplate 'S@h._q
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().findByNamedQuery(query, parameter); t+q:8HNh
} Q4CxtY
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publicList findByNamedQuery(finalString query, -]W AB9
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finalObject[] parameters){ A5y?|q>5
return getHibernateTemplate cXE42MM
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().findByNamedQuery(query, parameters); c5R58#XK=
} =WFMqBh<`
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publicList find(finalString query){ HMrS::
return getHibernateTemplate().find _4x X}Z;
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(query); sJw3o7@pg
} 9_5Fl,u
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publicList find(finalString query, finalObject Ko>pwhR}
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parameter){ Ol{)U;,`
return getHibernateTemplate().find `[VoW2CLH+
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(query, parameter); 1ncY"S/VO
} % ]r@vjeyd
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public PaginationSupport findPageByCriteria oizD:|
)/Ee#)z*
(final DetachedCriteria detachedCriteria){ e@NS=U` <
return findPageByCriteria 6b6}HO
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); T%
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} @m1v B!
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public PaginationSupport findPageByCriteria BqCBH!^x
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(final DetachedCriteria detachedCriteria, finalint 5?kF'yksR
@Zjy"u
startIndex){
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return findPageByCriteria q 1Rk'k4+
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(detachedCriteria, PaginationSupport.PAGESIZE, 'fy1'^VPAV
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startIndex); u6awcn
} z )a8
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public PaginationSupport findPageByCriteria ?VCb@&*
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(final DetachedCriteria detachedCriteria, finalint VbKky1a@
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pageSize, 4F??9o8 }
finalint startIndex){ 7'J}|m{7
return(PaginationSupport) j42U|CuK
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getHibernateTemplate().execute(new HibernateCallback(){ `.#e4 FBW
publicObject doInHibernate 6^if%62l&
*&% kkbA
(Session session)throws HibernateException { 8ooj)
Criteria criteria = 9"I/jd0B
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detachedCriteria.getExecutableCriteria(session); vp[~%~1(
int totalCount = UqsVqi
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((Integer) criteria.setProjection(Projections.rowCount (`<l" @:_*
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()).uniqueResult()).intValue(); Me`jh8(K\6
criteria.setProjection &t5pJ`$(Cy
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(null); Z>wg
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List items = <6Y o%xt
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criteria.setFirstResult(startIndex).setMaxResults 4 "@BbVYR
.%M=dL>
(pageSize).list(); S^c5
PaginationSupport ps = RI')iz?
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new PaginationSupport(items, totalCount, pageSize, cPPE8}PVH
1Ty{k^%
startIndex); `N_N zH
return ps; o/CSIvz1
} ;Tvy)*{
}, true); oi::/W|A+
} 1YTnOiYS1
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public List findAllByCriteria(final zX"@QB3E
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DetachedCriteria detachedCriteria){ HZ>Xm6DnC5
return(List) getHibernateTemplate CD +,&id
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().execute(new HibernateCallback(){ 2(\~z@g
publicObject doInHibernate ",B92[}Ar
#?@k=e\
(Session session)throws HibernateException { 5dXC
Criteria criteria = EZ8Ih,j9
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detachedCriteria.getExecutableCriteria(session); bO>Mvf
return criteria.list(); 3R
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} V/.Y]dN5
}, true); E@}t1!E<
} S@k4k^Vg
@-NdgM<
public int getCountByCriteria(final
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DetachedCriteria detachedCriteria){ 9} :n
Integer count = (Integer) zF>|
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getHibernateTemplate().execute(new HibernateCallback(){ $Dxz21|P7
publicObject doInHibernate h:Q*T*py
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(Session session)throws HibernateException { eRWTuIV6
Criteria criteria = 2ZNTj u7h
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detachedCriteria.getExecutableCriteria(session); 1ZJP.T`
return exiCy1[+
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criteria.setProjection(Projections.rowCount Eyxw.,rB/
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()).uniqueResult(); V&-pgxf;
} ac6L3=u\
}, true); "]f0wLzh
return count.intValue(); l5b?
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} .,)NDG4Q
} ~gNa<tg"1
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用户在web层构造查询条件detachedCriteria,和可选的 C&^"]-t
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2ro4{^(_
ex
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PaginationSupport的实例ps。 VC:.ya|Z
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ps.getItems()得到已分页好的结果集 ArDkJ`DE
ps.getIndexes()得到分页索引的数组 x=pq-&9>B
ps.getTotalCount()得到总结果数 6Z] * ce<r
ps.getStartIndex()当前分页索引 Y,RBTH
ps.getNextIndex()下一页索引 I dgha9K
ps.getPreviousIndex()上一页索引 [8EzyB>fH
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 AifnC4
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 \Bg;}\8X
cs `T7?>
一下代码重构了。 NRe{0U}nO
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我把原本我的做法也提供出来供大家讨论吧: paF$o6\
2 1.;lj
首先,为了实现分页查询,我封装了一个Page类: y#!8S{
java代码: HP}d`C5<R
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/*Created on 2005-4-14*/ jc)[5i0
package org.flyware.util.page; DF|(CQs9
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/** x9)^0Hbo
* @author Joa Lt$LXE
* P!q!+g
*/ |j($2.
publicclass Page { }SIUsh'
h W\q
/** imply if the page has previous page */ @iWql*K;m
privateboolean hasPrePage; H(GWC[tv
4,"%
/** imply if the page has next page */ Lgw!S~0
privateboolean hasNextPage; fA{[H:*}G
qN%i$mJTo
/** the number of every page */ A0Pg|M
privateint everyPage; dY'/\dJ
l ?RsXC
/** the total page number */ \_;zm+ <{
privateint totalPage; &,/_"N"?D
MO|aN,
/** the number of current page */ {XAm3's
privateint currentPage; oh
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/** the begin index of the records by the current Goa0OC,
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query */ ^t,sehpR:l
privateint beginIndex; \6~(#y
~ HFDX@m*
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/** The default constructor */ <pJeiMo
public Page(){ %2>ya>/M
w9h`8pt
} L6S!?t.{Yv
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/** construct the page by everyPage
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* @param everyPage QS.t_5<U
* */ M|IR7OtLV
public Page(int everyPage){ VX#4Gh,~N
this.everyPage = everyPage; 7~(|q2ib
} qk!")t
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/** The whole constructor */ SKO*x^"eU
public Page(boolean hasPrePage, boolean hasNextPage, ,?s3%<\2
$*a'[Qot#
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int everyPage, int totalPage, 7` AQn],
int currentPage, int beginIndex){ }Fy~DsQ
this.hasPrePage = hasPrePage; |]FJfMX
this.hasNextPage = hasNextPage; pV`?=[h9
this.everyPage = everyPage; N0TEVDsk
this.totalPage = totalPage; (0Buo#I
this.currentPage = currentPage; )1f8
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this.beginIndex = beginIndex; q {v?2v{
} h^QicvZ
IjJO;
/** {Yp>h5nwM_
* @return it?l! ~
* Returns the beginIndex. 2eNA#^T=
*/ RE~:+.eB
publicint getBeginIndex(){ t0t" =(d
return beginIndex; L9L!V"So1k
} &)Y26*(`
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/** ]3UEju8$
* @param beginIndex E2J.t`H
* The beginIndex to set. !58j xh
*/ q=Cc2|Ve
publicvoid setBeginIndex(int beginIndex){ ~@g7b`t=la
this.beginIndex = beginIndex; gG5@ KD6k
} ~:8}Bz2!5
s az<NT
/** Tp7*T8
* @return 3@xn<eu
* Returns the currentPage. [wKnJu
*/ kC~\D?8E=
publicint getCurrentPage(){ o1I8l7
return currentPage; YMGzO
} !@2L g
g?Jx99c;
/** aH@GhI^@
* @param currentPage :mOHR&2xR%
* The currentPage to set. G .PzpBA
*/ 9em?2'ysa
publicvoid setCurrentPage(int currentPage){ y"5>O|`
this.currentPage = currentPage; c*iZ6j"iI
} w, uyN
@0js=3!2
/** 19V
* @return H\W/;Nn
* Returns the everyPage. 9UF^h{X
*/ yMz%s=rh
publicint getEveryPage(){ ! n@*6
return everyPage; 0|mF
/
} osB8
'\GR
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/** hRKAs
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* @param everyPage ZcT%H*Ib]9
* The everyPage to set. A^\A^$|O6
*/ Ns3k(j16
publicvoid setEveryPage(int everyPage){ Zp:(U3%
this.everyPage = everyPage; /F/zMZGSA{
} V)HX+D>
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/** frsqnvm;+
* @return j A/xe
* Returns the hasNextPage. CJ'pZ]\G
*/ 53vnON#{*
publicboolean getHasNextPage(){ 6;|6@j
return hasNextPage; 7r,s+u.
} }r%Si
vR;?~^{*s
/** xV]eEOiLM
* @param hasNextPage 55aJ=T
* The hasNextPage to set. ZjCT * qx
*/ iA=QK
u!
publicvoid setHasNextPage(boolean hasNextPage){ }a=<Gl|I;w
this.hasNextPage = hasNextPage; #2&DDy)Bf
} M}jF-z
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/** V_)G=#6Dy
* @return (+M]C]
* Returns the hasPrePage. >j&+mii
*/ _tl
publicboolean getHasPrePage(){ 6I5,PB
return hasPrePage; H83Gx;
} *OoM[wEY
\U(;%V
/** .Oh4b5
* @param hasPrePage Etv!:\\[
* The hasPrePage to set. B;[ai?@c(_
*/ -eZ$wn![
publicvoid setHasPrePage(boolean hasPrePage){ rt5FecX\
this.hasPrePage = hasPrePage; c,wYXnJ_t
} &Nzq/~uqP
NI^=cN,l
/** |@Cx%aEKU
* @return Returns the totalPage. zk#NM"C+
* 0[\^Y<ec
*/ H]^hEQ3DT
publicint getTotalPage(){ w+,Kpb<x[0
return totalPage; ,RP"m#l!\
} T4
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olHT* mr
/** 2hD(zUSy
* @param totalPage c/K:`XP~
* The totalPage to set. )qyJwN
.D
*/ +JDQ`Qk
publicvoid setTotalPage(int totalPage){ X`,=tM
this.totalPage = totalPage; A }(V2
} blUnAu
o~
>
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} ^(w%m#
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V*}xlxSL
!]^,!7x,8j
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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 RB,`I#z1f
@ PboT1
个PageUtil,负责对Page对象进行构造: /Qa'\X,f3
java代码: E:_m6
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/*Created on 2005-4-14*/ O)2==_f\
package org.flyware.util.page; ?2RDd|#
G}|!Jdr
import org.apache.commons.logging.Log; As5*)o"&
import org.apache.commons.logging.LogFactory; "UNWbsn6Qr
9A7LDHst7
/** 9)y7K%b0
* @author Joa ){D6E9
* JY5)^<.d
*/ ~!t# M2Sk
publicclass PageUtil { E~4d6~s
[WfigqY`b*
privatestaticfinal Log logger = LogFactory.getLog %ZKP d8
%>)HAx `
(PageUtil.class); 7I#<w[l>k
d ynq)lf
/** >e'Hz (~'/
* Use the origin page to create a new page )o=ipm[
* @param page E]aQK.
* @param totalRecords ?KB+2]7m6
* @return \H^A@f
*/ X&bz%I>v
publicstatic Page createPage(Page page, int XCN^>ToD
6d# 7
totalRecords){ \me'B {aa
return createPage(page.getEveryPage(), _l ,_NV&T
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page.getCurrentPage(), totalRecords); ]"wl*$N
} _nn\O3TB
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/** :j<ij]rsI
* the basic page utils not including exception WDF;`o*3
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handler 2F
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* @param everyPage MsD@pa
* @param currentPage lTR/o
* @param totalRecords tCVaRP8eC+
* @return page 0etJ, _">
*/ 3g{T+c*
publicstatic Page createPage(int everyPage, int %v"qFYVX"
ozCH1V{p
currentPage, int totalRecords){ rGqT[~{t
everyPage = getEveryPage(everyPage); ]di^H>,xU
currentPage = getCurrentPage(currentPage); 4WAs_~
int beginIndex = getBeginIndex(everyPage, ^*$lCUv8p
ES>iM)M
currentPage); [YTOrN
int totalPage = getTotalPage(everyPage, N!Q~?/!d
g[%iVZ
totalRecords); !vY5X2?tr,
boolean hasNextPage = hasNextPage(currentPage, `Lr I^9Z
_!K@(dl
totalPage); Qt~QJJN?oF
boolean hasPrePage = hasPrePage(currentPage); tK0Ksnl^
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returnnew Page(hasPrePage, hasNextPage, `pJWZ:3
everyPage, totalPage, B/^1uPTZ71
currentPage, wBJP8wES=
c]x'}Kc
beginIndex);
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} CKuf'h#
V."qxKsz
privatestaticint getEveryPage(int everyPage){ qt.Y6s:r_
return everyPage == 0 ? 10 : everyPage; gP^p7aYwn
} .S6u{B
}rKKIF^f\S
privatestaticint getCurrentPage(int currentPage){ .B? J@,
return currentPage == 0 ? 1 : currentPage; 9^zA(
} oScKL#Hu
tB<2mjg
privatestaticint getBeginIndex(int everyPage, int *ak"}s
d^:(-2l-
currentPage){ ?AlTQL~c
return(currentPage - 1) * everyPage; )*m#RqLQ8
} bpaS(nBy
7,!$lT#
privatestaticint getTotalPage(int everyPage, int x 3C^ S~
8jdEx&K
totalRecords){ F<Y>
int totalPage = 0; WWtksi,
([Da*Tk*
if(totalRecords % everyPage == 0) h4,S/n
totalPage = totalRecords / everyPage; CY?19Ak-xd
else :&-j{8p-
totalPage = totalRecords / everyPage + 1 ; p( 6!7t:
An2Wj
return totalPage; 3x6@::s~
} Z&MfE0F/B
<],~V\m
privatestaticboolean hasPrePage(int currentPage){ bmd3fJb`r
return currentPage == 1 ? false : true; |Ev VS
} J69B1Yi
yu98d1
privatestaticboolean hasNextPage(int currentPage, .8~zgpK
[}1+=Ub
int totalPage){ ,enU`}9V*
return currentPage == totalPage || totalPage == =AVr<kP
XT<{J8
0z
0 ? false : true; s4kkzTnXE3
} y7LT;`A
f{j.jfl\x
c%O8h
} .G/2CVMj
,nnVHBN
=L F9im
dl;
]4
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 _rIFwT1]
\|< 5zL
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 #$*l#j"#A
okSCM#&:[2
做法如下: 7w8I6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 I7@g,~s
kM o7mkV
的信息,和一个结果集List: meM61ue_2
java代码: KU5|~1t 4
mvV5Xal
|.;LI=CT
/*Created on 2005-6-13*/ !3JYG
package com.adt.bo; ?T\_"G
xZ.c@u6:
import java.util.List; t^KoqJ
"U6:z M
import org.flyware.util.page.Page; +u[?8D7Y
zSM;N^X 8?
/** (Tbw@BFk
* @author Joa 5:6]ZFW
*/ - )brq3L
publicclass Result { o9 g0fC
|-!
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private Page page; idLCq^jnJ
*5Aq\g,n
private List content; ~K-_]*[x
4Px
/** lMW4SRk1C
* The default constructor GJB=5nE
*/ pQ/
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public Result(){ #nS[]UbwZ
super(); 0*umf.R
} 1}>u Y
%^VQw!
/** 9p '#a:
* The constructor using fields /:o (Ghc?
* !5escR!\D
* @param page MDqUl:]
* @param content %I>-_el
*/ Or9`E(
public Result(Page page, List content){ q(YFt*(;w
this.page = page; A=a~ [vre
this.content = content; -|\SNbPTV
} *M^t@ h l
{24Y1ohK
/** LjOHlT'
* @return Returns the content. di,?`
*/ Xj+oV
publicList getContent(){ WUesTA>
return content; ^+)q@{\8Y
} Gi*GFv%xB
wEp*j+Mmce
/** mE+
* @return Returns the page. Pcox~U/j
*/ `*to(
)
public Page getPage(){ hD I}V1)
return page; .)Af&+KT
} g-cC&)0Q
irRe}
/** e9e7_QG_-
* @param content eo~>|0A*V
* The content to set. v*UJ4r
*/ LsGu-Y5^
public void setContent(List content){ G"._]3CPF
this.content = content; tUR9ti
} >QJfTkD$
y7x[noGtR
/** j^&{5s
* @param page Il&}4#:
* The page to set. #FL\9RXy
*/ Q*h%'oc`
publicvoid setPage(Page page){ {95u^S=
this.page = page; <F7g;s'q9
} X8Ld\vZYn
} X|3l*FL
-jJw wOm
<GthJr>1D
oF9c>^s
./!6M
2. 编写业务逻辑接口,并实现它(UserManager, _s> ZY0
%C^%Oq_k
UserManagerImpl) /Wqx@#
java代码: jj&4Sv#>
FID4@--
O{F)|<L(G
/*Created on 2005-7-15*/ 7:>VH>?D
package com.adt.service; -Ze{d$
!;1$1xWK
import net.sf.hibernate.HibernateException; iNxuQ7~
6QC=:_M;
import org.flyware.util.page.Page; 7KzMa%=
G',*"mZQ[
import com.adt.bo.Result; /V%]lmxQ
{g7[3WRy
/** &D[pX|!
* @author Joa h)746T )
*/ P4~=_Hh
publicinterface UserManager { ggR--`D[
.{@aQwN
public Result listUser(Page page)throws 0/F/U=Z!
sivd@7r\Fa
HibernateException; '\iWp?`$
53w@
} ;N FTdP
=b* Is,R/
@/m|T]'8
ctzaqsr
+.RC{o,
java代码: jD
eNCJ
%%w/;o!c
S_B $-H|
/*Created on 2005-7-15*/ tKik)ei
package com.adt.service.impl; `S{Blv
R1%2]?
import java.util.List; 22<T.c
XazKS4(
import net.sf.hibernate.HibernateException; vj23j[!|
$YM6}D@
import org.flyware.util.page.Page; +C(v4@=nd
import org.flyware.util.page.PageUtil; vGT#BS%
Du3nK"-g
import com.adt.bo.Result; {0#p, l
import com.adt.dao.UserDAO; WLTraB[?
import com.adt.exception.ObjectNotFoundException; -p:X]Ov
import com.adt.service.UserManager; J} 03 5
RNJUA^{
/** 0H6^2T<
* @author Joa 1{.=T&eG#
*/ mu1Lg s$;
publicclass UserManagerImpl implements UserManager { 8>}^W
s]X]jfA.
private UserDAO userDAO; P
K]$D[a0
4ZZ/R?AiK
/** gDmwJr
* @param userDAO The userDAO to set. Nm0kMq|h
*/ zgdOugmmt_
publicvoid setUserDAO(UserDAO userDAO){ {Y%X
this.userDAO = userDAO; /
xfg4
} v=~=Q*\l
`Xbk2KD p
/* (non-Javadoc) $:YJ<HvG<
* @see com.adt.service.UserManager#listUser y'9
bs
&m'ttUG?
(org.flyware.util.page.Page) ?d -$lI
*/ 3xJ_%AD\'
public Result listUser(Page page)throws ~\9bh6%R
CS:mO|
HibernateException, ObjectNotFoundException { "z^&>#F
int totalRecords = userDAO.getUserCount(); 5Y4i|R
if(totalRecords == 0) zLs[vg.(
throw new ObjectNotFoundException LZCziW
l1|z;
$_z
("userNotExist"); }wJDHgt]-p
page = PageUtil.createPage(page, totalRecords); -n-rKN.T
List users = userDAO.getUserByPage(page); ;!CYp;_
returnnew Result(page, users); ydNcbF%K
} mkCv
f
l+>&-lX'
} ?T\m
V}
l"\W] 'T:r
0#}@-e
X:*Ut3"
Q&Rj)1!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Daa2.*
NC*h7
询,接下来编写UserDAO的代码: O^D$ ~
]
3. UserDAO 和 UserDAOImpl: LN8V&'>
java代码: O1.a=O
Om%9 x
/;%[:x
/*Created on 2005-7-15*/ ;)^eDJ<
package com.adt.dao; {I!sXj
By
t{3$
import java.util.List; aqjS 5!qh
~$0Qvyb>
import org.flyware.util.page.Page; 0YsC@r47wL
{-sy,EYcw
import net.sf.hibernate.HibernateException; Q1G?e,Q
iB Ld*B|#K
/** GRanR'xG
* @author Joa n')#]g0[
*/ `hD\u@5Tw
publicinterface UserDAO extends BaseDAO { 2VOdI
(9N75uCa
publicList getUserByName(String name)throws wn'_;0fg
}ug|&25D
HibernateException; {YCquoF
EHT5Gf
publicint getUserCount()throws HibernateException; ndkV(#wQS
PNSZ
j#
publicList getUserByPage(Page page)throws -ISI!EU$
bF88F_
HibernateException; mCtuR*z_
3N?WpA768/
} FTtGiGd|Zy
*g^U=t
M]?#]3XBNo
_5^p+
V`KXfY
java代码: U@<>2
Ix,`lFbH
N#')Qz:P
/*Created on 2005-7-15*/ Go}C{(4T
package com.adt.dao.impl; I$4GM
C:n55BE9
import java.util.List; Q(-:)3g[aL
^ ~HV`s
import org.flyware.util.page.Page; m8F-#?~
T jO}P\p
import net.sf.hibernate.HibernateException; s4 o-*1R*`
import net.sf.hibernate.Query; bJD2c\qoc
TxYxB1C)
import com.adt.dao.UserDAO; VJM n5v[V
L;=<d
/** Gw6*0&3')
* @author Joa u4L&8@
*/ +_gPZFpbx
public class UserDAOImpl extends BaseDAOHibernateImpl n&x#_B-
5N(/K. ^
implements UserDAO { 3QDz0ct
-Cxk#-sb#
/* (non-Javadoc) n&=3Knbd@d
* @see com.adt.dao.UserDAO#getUserByName lvi~GZ
;T! mNKl
(java.lang.String) %+iJpRK)7
*/ sgDlT=c'
publicList getUserByName(String name)throws )TxAhaz+
~Dw.3P:-
HibernateException { CUB= T]
String querySentence = "FROM user in class T<\Q4Coth
2G8f4vsC[
com.adt.po.User WHERE user.name=:name"; o$>A;<
Query query = getSession().createQuery "
1YARGu
tL1"Dt>
(querySentence); u>j:8lhtV
query.setParameter("name", name); x68$?CD
return query.list(); sm-RpZ&|
} "Y9
*rL
Exox&T
/* (non-Javadoc) 'vT
XR_D
* @see com.adt.dao.UserDAO#getUserCount() &ZgB b
*/ 2{zFO3i<3
publicint getUserCount()throws HibernateException { |q5R5mQ
int count = 0; :Vc+/ZyW
String querySentence = "SELECT count(*) FROM &[}T41
n83,MV?-
user in class com.adt.po.User"; }E+}\&
Query query = getSession().createQuery >ZKE
yz!j9pJ
(querySentence); IiV:bHUE}0
count = ((Integer)query.iterate().next p%_#"dkC7
s5>=!yX
()).intValue(); `d,hP"jBc
return count; -"iGcVV
} 5QU7!jbI
R=~+- ^O!
/* (non-Javadoc) U]lXw+&
* @see com.adt.dao.UserDAO#getUserByPage DQ^yqBVgQ
oJy ]n9
(org.flyware.util.page.Page) [^B04x@
*/ _ 97
publicList getUserByPage(Page page)throws w?A&X