Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Rz%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 jG=*\lK6
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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 Rfh#JO@%[
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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 zRtaO'G(
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分页支持类: AP.WTFf
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java代码: 3c] oU1GfF
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package com.javaeye.common.util; oeKI9p13\
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import java.util.List; F`,XB[}2
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publicclass PaginationSupport { (!kOM% 3{
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publicfinalstaticint PAGESIZE = 30; B:qH7`s
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privateint pageSize = PAGESIZE; zR:Mg\
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privateList items; }{;m:Iia_
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privateint totalCount; xsS/)R?
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privateint[] indexes = newint[0]; 4L#q?]$
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privateint startIndex = 0; g2L^cP>2
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public PaginationSupport(List items, int #W[/N|~wx
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totalCount){ 0eq="|n^|
setPageSize(PAGESIZE); 2\&uO
setTotalCount(totalCount); 6wH]W+A
setItems(items); t4)~A5s
setStartIndex(0); HRO:U%
} 7z!|sPW](b
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public PaginationSupport(List items, int `Q?rQ3A}
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totalCount, int startIndex){ X%Jq9_
setPageSize(PAGESIZE); to~Ap=E
setTotalCount(totalCount); B3[;}8u>
setItems(items); d
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setStartIndex(startIndex); d5&avL\
} -g8G47piX:
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public PaginationSupport(List items, int o= VzVg
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totalCount, int pageSize, int startIndex){ 3'WJx=0?
setPageSize(pageSize); [#$: X+lw
setTotalCount(totalCount); EGWm0 F_
setItems(items); _j t>%v4}4
setStartIndex(startIndex); gj{2"tE
} 7+wy`xi
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publicList getItems(){ 4'JuK{/ A7
return items; p^PAbCP'|3
} `tKrTq>
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publicvoid setItems(List items){ GUyMo@g
this.items = items; :tclYX
} kj_o I5<'
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publicint getPageSize(){ 5,
return pageSize; k?-GI[@X
} %5<uQc9
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publicvoid setPageSize(int pageSize){ 9UlR fl
this.pageSize = pageSize; Ax &Z=
} @H%)!f]zWt
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publicint getTotalCount(){ B3 f Kb#T
return totalCount; 1#LXy%^tO
} +>BLox6
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publicvoid setTotalCount(int totalCount){ ;tK%Q~To
if(totalCount > 0){ [JI>e;l
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this.totalCount = totalCount; B->3/dp2c'
int count = totalCount / n.+%eYM<
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pageSize; 9z>I&vcX
if(totalCount % pageSize > 0) MDkcG"O
count++; Mrpz (})
indexes = newint[count]; tf?syk+jB7
for(int i = 0; i < count; i++){ 3$x[{\ {
indexes = pageSize * SM%N]/@U
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} xz!b@5DR'%
}else{ VRe7Q0
this.totalCount = 0; -!_f-Nny
} ) -yJKmV
} xi5G?r
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publicint[] getIndexes(){ lG[@s 'j
return indexes; +f h@m
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} }_,\yC9F
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publicvoid setIndexes(int[] indexes){ |"}F cS
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this.indexes = indexes; IXjFK
} O9%`G
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publicint getStartIndex(){ 4oxAC; L
return startIndex; JATW'HWC|I
} -"Mq<XO&51
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publicvoid setStartIndex(int startIndex){ :#_Ne?\a@
if(totalCount <= 0) Z5x&P_.x[
this.startIndex = 0; >* Ag0.Az
elseif(startIndex >= totalCount) =@e3I)D#?i
this.startIndex = indexes S10"yhn(-t
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[indexes.length - 1]; j
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elseif(startIndex < 0) E; `@S
this.startIndex = 0; pCacm@(hG
else{ $<NrJgQ
this.startIndex = indexes |DUWB;
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[startIndex / pageSize]; HB|R1<t;HB
} v3p'*81;
} e\8|6<o[
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publicint getNextIndex(){ u;
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int nextIndex = getStartIndex() + }}?,({T|n
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pageSize; b((>?=hh
if(nextIndex >= totalCount) Lg%3M8-W~
return getStartIndex(); U ;%cp
else NIo!WOi
return nextIndex; cFD3
} &~Hx!]uc
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publicint getPreviousIndex(){ o=]\Jy
int previousIndex = getStartIndex() - R:+cumHr
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pageSize; iNCT( N~.
if(previousIndex < 0) Tr@|QNu
return0; 7Gwo:s L
else @sdHB./
return previousIndex; zG*
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} :pH3M[7
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} f1$'av
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抽象业务类 goqm6L^Cu
java代码: J?9n4
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/** oQiRjDLx
* Created on 2005-7-12 -=WQed}
*/ *'cyFu$
package com.javaeye.common.business; L$z(&%Nx
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import java.io.Serializable; ]3Y J a
import java.util.List; =5;tB
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import org.hibernate.Criteria; Q?2GwN
import org.hibernate.HibernateException; \0veld
import org.hibernate.Session; a@S{A5j
import org.hibernate.criterion.DetachedCriteria; dK Qu
import org.hibernate.criterion.Projections; 3;JF5e\?x
import ^WkqRs
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org.springframework.orm.hibernate3.HibernateCallback; 9e*o$)j_
import UOpSH{N
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org.springframework.orm.hibernate3.support.HibernateDaoS #62*'.B4
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upport; V!Pe%.>
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import com.javaeye.common.util.PaginationSupport; l@0${&n
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public abstract class AbstractManager extends BJgHel+N
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HibernateDaoSupport { 9H/C(Vo
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privateboolean cacheQueries = false; _fdD4-2U
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privateString queryCacheRegion; pr[V*C/
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publicvoid setCacheQueries(boolean \UP=pT@
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cacheQueries){ p}Um+I=1
this.cacheQueries = cacheQueries; UX'q64F!
} e'sS",o*
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publicvoid setQueryCacheRegion(String R7 rO7M!
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queryCacheRegion){ {"2Hv;x
this.queryCacheRegion = z(u,$vZ_
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queryCacheRegion; 3+\Zom4
} yIC
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publicvoid save(finalObject entity){ ^u2x26].
getHibernateTemplate().save(entity); kC ALJRf~d
} /BN=Kl]
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publicvoid persist(finalObject entity){ =w3 cF)&
getHibernateTemplate().save(entity); d)3jkHYEjj
} 9C8 G(r
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publicvoid update(finalObject entity){ bXeJk]#y
getHibernateTemplate().update(entity); KF1Zy;
} G?, "AA;
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publicvoid delete(finalObject entity){ GO.7IL{{
getHibernateTemplate().delete(entity); @}
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} nly}ly Q/
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publicObject load(finalClass entity, ;<*USS6X
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finalSerializable id){ 3ZN\F
return getHibernateTemplate().load ~xv3R
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(entity, id); })`z6d]3
} r7#.DJnN.
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publicObject get(finalClass entity, ,xR u74
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finalSerializable id){ lWH#/5`h
return getHibernateTemplate().get 3}8L!2_p
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(entity, id); c^cr_i
} D+jE{v'
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publicList findAll(finalClass entity){ ?~IdPSY
return getHibernateTemplate().find("from >JA>np
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" + entity.getName()); ~W={"n?=
} t3g+>U_m
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publicList findByNamedQuery(finalString BR-wL3x
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namedQuery){ Jamt@=
return getHibernateTemplate ?Q$a@)x#
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().findByNamedQuery(namedQuery); a#G3 dY>
} *wsZ aQ
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publicList findByNamedQuery(finalString query, 4"3.7.<Q`
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finalObject parameter){ ^7*7^<
return getHibernateTemplate ._t1eb`m{
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().findByNamedQuery(query, parameter); y<wd~!>Ubu
} xX9snSGz
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ o2hk!#5[4
return getHibernateTemplate ?Z4%u8Krvz
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().findByNamedQuery(query, parameters); :bi(mX7t
} eX lJ=S}
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publicList find(finalString query){ ?Bl/bY$*h
return getHibernateTemplate().find fBh/$
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(query); 8h4]<T
} #U7pT!Fx
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publicList find(finalString query, finalObject Yh;(puhyA
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parameter){ cH4PrMm&
return getHibernateTemplate().find c`UFNNm=
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(query, parameter); g oyQ',+
} L,
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public PaginationSupport findPageByCriteria I} 5e{jBB
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(final DetachedCriteria detachedCriteria){ : vx<m_
return findPageByCriteria RLL%l
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); diVg|Z3T
} m[iQ7/
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public PaginationSupport findPageByCriteria #$W0%7
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(final DetachedCriteria detachedCriteria, finalint ?8?vBkz~
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startIndex){ -Ah&|!/
return findPageByCriteria INp:;
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(detachedCriteria, PaginationSupport.PAGESIZE, m"n" 1;o=
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startIndex); 98O]tL+k/u
} K/*"U*9Kv
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public PaginationSupport findPageByCriteria 3A[<LnKR^E
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(final DetachedCriteria detachedCriteria, finalint Ovj^
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pageSize, E{e
finalint startIndex){ Oq,@{V@)9k
return(PaginationSupport) TF5jTpGq
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getHibernateTemplate().execute(new HibernateCallback(){ 'W4v>0
publicObject doInHibernate m&DI2he
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(Session session)throws HibernateException { 0'.z|Jg=
Criteria criteria = s]0 J'UN
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detachedCriteria.getExecutableCriteria(session); ;~djbo0,X
int totalCount = ~o|sm a5.
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((Integer) criteria.setProjection(Projections.rowCount 2yZ~j_AF[
ts@Z5Yw*!
()).uniqueResult()).intValue(); %t!r
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criteria.setProjection (VI(Nv:o@
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(null); n'{jc6&|
List items = pX*E(Q)@!
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criteria.setFirstResult(startIndex).setMaxResults GD
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(pageSize).list(); +/eJ#Xw3u8
PaginationSupport ps = kONn7Itbu
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new PaginationSupport(items, totalCount, pageSize, }vx,i99W?
SqRM*Cf=
startIndex); YQFz6#Ew
return ps; "=C~IW
} AB,(%JT/2{
}, true); u,`3_I^
} }~PG]A
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public List findAllByCriteria(final eN
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DetachedCriteria detachedCriteria){ }vOg9/[{
return(List) getHibernateTemplate 7 kA+F+f
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().execute(new HibernateCallback(){ KehM.c^
publicObject doInHibernate +zk5du^gZ
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(Session session)throws HibernateException { ^z{Xd|{"
Criteria criteria = &Z!y>k%6
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detachedCriteria.getExecutableCriteria(session); ,xrA2
return criteria.list(); :=+YZ|&j
} \?Z7|
}, true); I ~YV&12
} d*04[5`
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public int getCountByCriteria(final "s]
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DetachedCriteria detachedCriteria){ i%<NKE;v7m
Integer count = (Integer) -zJV(`
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getHibernateTemplate().execute(new HibernateCallback(){ ~8(Xn2
publicObject doInHibernate ^q/$a2<4
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(Session session)throws HibernateException { jck(cc=R
Criteria criteria = 3)o>sp)Ji$
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detachedCriteria.getExecutableCriteria(session); -Q5UT=^
return 1'(";
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criteria.setProjection(Projections.rowCount ?q Q.Wj6Mj
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()).uniqueResult(); !T:7xEr
} >7cj.%
}, true); 0[<'ygu
return count.intValue(); h`O$L_Z
} hS &H*
} `^on`"\{u
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用户在web层构造查询条件detachedCriteria,和可选的 \r{wNqyv
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {E)tzBI;^
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PaginationSupport的实例ps。 {6Nbar@3
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ps.getItems()得到已分页好的结果集 `
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ps.getIndexes()得到分页索引的数组 sh` 3$ {
ps.getTotalCount()得到总结果数 &YD+s%OL
ps.getStartIndex()当前分页索引 ,\3Cq2h
ps.getNextIndex()下一页索引 5%V(eR
ps.getPreviousIndex()上一页索引 [)8O\/:
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 47*2QL^zj
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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 $I#~<bW,
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一下代码重构了。 Bonj K#
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我把原本我的做法也提供出来供大家讨论吧: xN>\t& c
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首先,为了实现分页查询,我封装了一个Page类: -H[@]Q4w
java代码: r]QeP{
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/*Created on 2005-4-14*/ =Ov,7<8o
package org.flyware.util.page; F/tRyq`D
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/** .ty2! .
* @author Joa 9<P%?Q
* SLN OOEN
*/ F>[^m Xw
publicclass Page { 7OXRR)]V
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/** imply if the page has previous page */ <bhJ >
privateboolean hasPrePage; >k=@YLj
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/** imply if the page has next page */ @RoU
privateboolean hasNextPage; ^n4aoj
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/** the number of every page */ I7'v;*
privateint everyPage; /Q#eP m
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/** the total page number */ o?.VW/"
privateint totalPage; {ynI]Wj`L
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/** the number of current page */ Z~|%asjFE
privateint currentPage; TDg<&ND3
k#mL4$]V5N
/** the begin index of the records by the current | -Gb Hfz
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query */ vZ=dlu_t
privateint beginIndex; }>YEtA
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/** The default constructor */ V{qR/
public Page(){ r>"l:GZ
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} = P$7
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/** construct the page by everyPage LR"7e
* @param everyPage /B{cL`<
* */ ._'.F'd
public Page(int everyPage){ >DzW OB
this.everyPage = everyPage; #.OCoc
} \C1`F[d_
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/** The whole constructor */ Q b5vyV `
public Page(boolean hasPrePage, boolean hasNextPage, 3%N!omAe
LN'})CI8m
@_;vE(!5
int everyPage, int totalPage, c+1<3)Q<
int currentPage, int beginIndex){ +6<g N[
this.hasPrePage = hasPrePage; de"+ABR
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; f2Tz5slE
this.totalPage = totalPage; 5VLC\QgK^
this.currentPage = currentPage; h61BIc@>
this.beginIndex = beginIndex; r"KW\HN8
} ;|Rrtf9
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/** p;2NO&
* @return M8FC-zFs
* Returns the beginIndex. re@OPiXa v
*/ {w9GMqq
publicint getBeginIndex(){ QWwEfL
return beginIndex; ~ \7peH%
} ~t.i;eu
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/** w"E.Va
* @param beginIndex 0"c(n0L
* The beginIndex to set. lXrAsm$
*/ j"P}Wn
publicvoid setBeginIndex(int beginIndex){ _^] :tL6
this.beginIndex = beginIndex; {UOR_Vt!*
} 3Et t9fBd
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/** Hl*/s
* @return uhr&P4EW
* Returns the currentPage. /m*+N9)
*/ 6^Ax3#q
publicint getCurrentPage(){ f`,isy[
return currentPage; ZfWF2%]<
} jb!15Vlt"
os`#:Ao5
/** 83gp'W{|
* @param currentPage $3:O}X>
* The currentPage to set. K<D=QweOon
*/ 9uA2M!~i2
publicvoid setCurrentPage(int currentPage){ G\o*j|
this.currentPage = currentPage; Hd0?}w\
} L[p[m~HjG^
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/** p?4h2`P
* @return H83/X,"!w
* Returns the everyPage. dfA4OZ&
*/ SXm Hn.?
publicint getEveryPage(){ OLgW.j:Ag
return everyPage; SRpPLY{:F
} ~;B@ {kFY)
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/** %oN5 jt
* @param everyPage !TdbD56
* The everyPage to set. i slg5
*/ t"L-9kCM
publicvoid setEveryPage(int everyPage){ b'5L|1d
this.everyPage = everyPage; o+.LG($+U
} m%G:|`f7
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/** -H(\[{3{V
* @return p$OkWSi~
* Returns the hasNextPage. lQnqPQY
*/ CYWL@<p,
publicboolean getHasNextPage(){ kc&MO`2 W\
return hasNextPage; >YW_}kd
} d%='W|i\p&
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/** A5LTgGzaW
* @param hasNextPage ;`MKi5g
* The hasNextPage to set. f)/5%W7n}
*/ ?3{:[*
publicvoid setHasNextPage(boolean hasNextPage){ idh5neyL
this.hasNextPage = hasNextPage; zw,=mpf3_
} 3BWYSJ|
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/** XAf,k&f3
* @return }Kc03Ue`%e
* Returns the hasPrePage. )cd5iE:FO
*/ ?$&iVN^UA
publicboolean getHasPrePage(){ 2En^su$
return hasPrePage; l;C00ZBOc
} ndU<,{r
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/** Z_qOQ%l
* @param hasPrePage s;eOX\0
* The hasPrePage to set. xmI!N0eta
*/ xJ18M@"j
publicvoid setHasPrePage(boolean hasPrePage){ ui\yY3?
this.hasPrePage = hasPrePage; m$X0O_*A
} "}(g3Iy
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/** j~@Hj$APa`
* @return Returns the totalPage. CtO `t5
* <$]=Vaq
*/ ~Kr_[X:d5
publicint getTotalPage(){ .0b$mSV[
return totalPage; hkhk,bhI
} ~jDG&L
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/** @{|vW
* @param totalPage ^mA ^7jB
* The totalPage to set. (`
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*/ cU^Z=B
publicvoid setTotalPage(int totalPage){ Bi'qy]%
this.totalPage = totalPage; ksB-fOv*N
} */ ~_ 3
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} 1D6F
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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 AP8YY8,
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个PageUtil,负责对Page对象进行构造: 4*K~6Vh
java代码: YF]W<ZpY
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/*Created on 2005-4-14*/ VX!UT=;
package org.flyware.util.page; $i^#KZ}-WK
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import org.apache.commons.logging.Log; iAOm[=W
import org.apache.commons.logging.LogFactory; P}AfXgr
># {,(8\
/** 8N8N)#A[
* @author Joa a=m7pe^
* bP4<q?FKcN
*/ ac-R q.GQY
publicclass PageUtil { Oc|`<^m
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privatestaticfinal Log logger = LogFactory.getLog ?G48GxJ
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(PageUtil.class); `pHlGbrW
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/** eq|G\XJ
* Use the origin page to create a new page ?x*Ve2+]
* @param page :2qUel\PEC
* @param totalRecords HH\6gs]u
* @return Guc~]
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*/ 8b^v@|)N
publicstatic Page createPage(Page page, int Jj~c&LxrO
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totalRecords){ FXHcy:)}G
return createPage(page.getEveryPage(), &m>yY{be
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page.getCurrentPage(), totalRecords); (#dwIBBFt
} %|6t\[gn
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/** DPU%4te
* the basic page utils not including exception 5BL4VGwJ
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handler
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* @param everyPage |
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* @param currentPage [@l:C\2
* @param totalRecords HG1)q\Xd
* @return page jkPye{j
*/ qhKW6v
publicstatic Page createPage(int everyPage, int AI$r^t1
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currentPage, int totalRecords){ P4M*vZq)
everyPage = getEveryPage(everyPage); f{b$Y3
currentPage = getCurrentPage(currentPage); *r
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int beginIndex = getBeginIndex(everyPage, aR
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*1}UK9X;
currentPage); kl0!*j
int totalPage = getTotalPage(everyPage, X-tc Ud
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totalRecords); Ur`jmB
boolean hasNextPage = hasNextPage(currentPage, AgOw{bJ%
6D[m}/?Uy
totalPage); 1;; is
boolean hasPrePage = hasPrePage(currentPage); JGJXV3AT
/[[_}\xI%
returnnew Page(hasPrePage, hasNextPage, eV?._-G
everyPage, totalPage, H nKO
currentPage, .|[5*-
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beginIndex); sH//*y
} Orb('Z,-3
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privatestaticint getEveryPage(int everyPage){ j}0W|*
return everyPage == 0 ? 10 : everyPage; i.eu$~F
} !`u
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privatestaticint getCurrentPage(int currentPage){ T-0[P;
return currentPage == 0 ? 1 : currentPage; (*.t~6c?5
} ZT
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privatestaticint getBeginIndex(int everyPage, int 3GH@|id
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currentPage){ eR'Df"+
return(currentPage - 1) * everyPage; <<43'N+
} 8Ol#-2>k$
dQ4VpR9|;
privatestaticint getTotalPage(int everyPage, int NWuJ&+gcO5
=j%B`cJ66_
totalRecords){ n:hHm,
int totalPage = 0; K`=O!;
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if(totalRecords % everyPage == 0) 0]x g E
totalPage = totalRecords / everyPage; hXsd12
else BPp`r_m8w}
totalPage = totalRecords / everyPage + 1 ; /Iwnl
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return totalPage; pYtG%<
} d(.e%[`
L* k[Vc
privatestaticboolean hasPrePage(int currentPage){ (!-gX"<b
return currentPage == 1 ? false : true; H%,jB<-.A
} 8MHYk>O~{G
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privatestaticboolean hasNextPage(int currentPage, K[tQ>C@s2
. ZuRH_pI
int totalPage){ ' `0kW_'
return currentPage == totalPage || totalPage == R,mOV8y"W[
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0 ? false : true; d|GQZAEJEt
} uSZCJ#'G
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} OE{{,HFa`G
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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。 :}QBrd
lHRs3+
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 tDWW
4H
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做法如下: ^*CvKCS
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Y7WxV>E
}6;K+INT
的信息,和一个结果集List: N_dHPa
java代码: N?xZ]?T
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/*Created on 2005-6-13*/ !Tc
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package com.adt.bo; sK)fEx
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import java.util.List; LAe>XF-5
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import org.flyware.util.page.Page; 2nNBX2o&_
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/** o!R.QI^2VT
* @author Joa {1 VHz])I
*/ 75@!j[QL<
publicclass Result { ?vmu,y
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private Page page; u/wWP4'$J@
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private List content; AcZ{B<
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/** w=NM==cLj
* The default constructor $|kq{@<
*/ ?c G~M|@
public Result(){ JD`IPQb~E
super(); s$%t*T2J>
} /
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nt 9LBea
/** BiFU3FlTf
* The constructor using fields *~h@K Qm7
* 1 X8P v*,
* @param page +3>)r{#k
* @param content jHPkfwfAF
*/ oI\Lepl*
public Result(Page page, List content){ ,6J{-Iu
this.page = page; ~Q+E" "
this.content = content; Ow#a|@
} Zz,j,w0 Z
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/** F"-u8in`
* @return Returns the content. ?-Qq\D^+
*/ g~7x+cu0
publicList getContent(){ 3_DwqZ 'O
return content; qjBF]3%t%
} RJ\'"XQ
}1xD*[W
/** VQ R
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* @return Returns the page. 1"\^@qRv#
*/ &@v&5EXOw
public Page getPage(){ x/S:)z%X
return page; gLDO|ADni
}
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/** e,?qwZK:y
* @param content wsKOafrV
* The content to set. Jkx_5kk/\
*/ 'bQjJRq!
public void setContent(List content){ 5i0vli/L
this.content = content; ~D0e\Q(A
} `o4%UkBpM
LJgGX,Kp
/** (y^svXU}a
* @param page qg06*$%
* The page to set. 0Yk$f1g
*/ &cpqn2Z
publicvoid setPage(Page page){ I.6
qA *
this.page = page; <WiyM[ep
} EXbaijHQG
} H5eGl|Z5]^
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vWH)W?2
A4tb>OM
7~qyz]KkE
2. 编写业务逻辑接口,并实现它(UserManager, ii5dTimRJ
:^En\YcU
UserManagerImpl) LOEiV
java代码: ]<BT+6L
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sTu]C +A
/*Created on 2005-7-15*/ 8U)*kmq
package com.adt.service; 0K(&EpVE
s?Z{LWZ@
import net.sf.hibernate.HibernateException; ZK4d;oa",
l+#uQo6cqQ
import org.flyware.util.page.Page; >sGiDK @
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^';
import com.adt.bo.Result; <u}[_
zXW)v/
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/** P
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* @author Joa O%1uBc
*/ Y#zHw<<E
publicinterface UserManager { Gm[XnUR7V
{%D4%X<
public Result listUser(Page page)throws P]0/ S
d$HPpi1LL
HibernateException; v[4-?7-
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} 5
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}E^k*S
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java代码: !}hG|Y6s
b"y4-KV
h,ipQ>
/*Created on 2005-7-15*/ UmL Boy&*
package com.adt.service.impl; t+#vcg,G
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import java.util.List; =@P]eK/
ap<r)<u
import net.sf.hibernate.HibernateException; skF}_
1Q7]1fRu
import org.flyware.util.page.Page; zym6b@+jN
import org.flyware.util.page.PageUtil; M7=|N:/_
32p9(HQ
import com.adt.bo.Result; A3.*d:A
import com.adt.dao.UserDAO; 9vBW CCf
import com.adt.exception.ObjectNotFoundException; 1cS*T>`
import com.adt.service.UserManager; _2WW0
t;}`~B
/** 5nXmaj
* @author Joa "}2I0tM
*/ J;N\q
publicclass UserManagerImpl implements UserManager { fW$1f5g"
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private UserDAO userDAO; ),lE8A{ H
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/** Lb~'
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* @param userDAO The userDAO to set. =vsvx{o?
*/ v,Z?pYYo
publicvoid setUserDAO(UserDAO userDAO){ XHm6K1mGZ
this.userDAO = userDAO; ft$!u-`
} !`dMTW
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/* (non-Javadoc) 7w}]9wCN?
* @see com.adt.service.UserManager#listUser Qx8O&C?Ti
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(org.flyware.util.page.Page) !O4)YM
*/ |=[._VH1
public Result listUser(Page page)throws P:UR:y([
e
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HibernateException, ObjectNotFoundException { \=H+m%
int totalRecords = userDAO.getUserCount(); s0'6r$xj
if(totalRecords == 0) ^@<Ia-x
throw new ObjectNotFoundException YoSBS
|$[.X3i
("userNotExist"); `We?j7O
page = PageUtil.createPage(page, totalRecords); MC1&X'
List users = userDAO.getUserByPage(page); :Aj[#4-=
returnnew Result(page, users); F#z1 sl'
} +*G<xW :M
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} } a!HbH
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 OG^#e+
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询,接下来编写UserDAO的代码: %-an\.a.
3. UserDAO 和 UserDAOImpl: JykN EMB#
java代码: L(}/W~En
GD4+f|1.*
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/*Created on 2005-7-15*/ (R!`Z%
package com.adt.dao; Z& bIjp
&