Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 O#x=iZI
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 aQglA
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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 WSOz^]
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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 -qdt$jIM
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分页支持类: 1}3tpO;
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java代码: gvoYyO#cm
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package com.javaeye.common.util; sI6coe5n
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import java.util.List; r>B|JPm
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publicclass PaginationSupport { 1;eWnb(
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publicfinalstaticint PAGESIZE = 30; cr ~.],$Om
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privateint pageSize = PAGESIZE; W(Rp@=!C
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privateList items; l;}3J3/qq]
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privateint totalCount; 7R$O~R3p
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privateint[] indexes = newint[0]; -mLS\TF S
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privateint startIndex = 0; 5Kw?#
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public PaginationSupport(List items, int U;t1 K
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totalCount){ qIvnPaYW
setPageSize(PAGESIZE); [G'
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setTotalCount(totalCount); 4|;Ys-Q
setItems(items); $+$4W\-=X
setStartIndex(0); vL8Rg} Jh4
} zJo?,c
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public PaginationSupport(List items, int H:cAORLB
+`uNO<$~f
totalCount, int startIndex){ c/E'GG%Q%
setPageSize(PAGESIZE); _RE;}1rb,
setTotalCount(totalCount); st)qw]Dn;Y
setItems(items); i@mS8%|l
setStartIndex(startIndex); i(>
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} -`UOqjb]3
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)
public PaginationSupport(List items, int P|t2%:_
jc HyRR1R
totalCount, int pageSize, int startIndex){ lcK4 Uq\q
setPageSize(pageSize); ;.=]Ar}
setTotalCount(totalCount); n0g8B
setItems(items); 7MQh,J!"
setStartIndex(startIndex); &z@}9U*6b
} I>{o]^xw-D
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publicList getItems(){ c2-oFLNP=
return items; Y=t?"E
} IZs&7
J vq)%t8q>
publicvoid setItems(List items){ ik1asj1
this.items = items; <Yg6=e
} VxtX%McK
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publicint getPageSize(){ #HZ W57"
return pageSize; |5jrl|
} Up0kTL
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publicvoid setPageSize(int pageSize){ AG><5 }
this.pageSize = pageSize; ,0{x-S0jX<
} xxA^A
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publicint getTotalCount(){ 7^tYtMm|U
return totalCount; YdyTt5-
} $gZiW 8
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publicvoid setTotalCount(int totalCount){ )!~,xl^j{}
if(totalCount > 0){ NxnaH!wS
this.totalCount = totalCount; WyRSy-{U(}
int count = totalCount / H!'4A&
mZO-^ct4
pageSize; F)4I70vG
if(totalCount % pageSize > 0) L7R!,
count++; rdCs
indexes = newint[count]; >Y(JC#M;
for(int i = 0; i < count; i++){ 6|IJwP^Q_
indexes = pageSize * z/fSstN
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i; #8zC/u\`=
} r6GXmr
}else{ 6\k~q.U@XI
this.totalCount = 0; &hrMpD6z6i
} Lp/'-Y_
} !{ fu(E
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publicint[] getIndexes(){ iiF`2
return indexes; +*,!q7Gt
} e N v\ZR1
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publicvoid setIndexes(int[] indexes){ Uz~B`
this.indexes = indexes; Y>atJ
} <@[;IX`YN
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publicint getStartIndex(){ 6TTu[*0NT
return startIndex; aRElk&M
} 8!YQ9T [
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publicvoid setStartIndex(int startIndex){ /:ZwGyT;
if(totalCount <= 0) (:F]@vT
this.startIndex = 0; ~f"3Wa*\B
elseif(startIndex >= totalCount) kR3wbA
this.startIndex = indexes %a|Qw(4\
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[indexes.length - 1]; &nwS7n1eb
elseif(startIndex < 0) EIfqRRTA
this.startIndex = 0; ]#W7-Q;]
else{ H4sW%nZ0
this.startIndex = indexes m(o`;
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[startIndex / pageSize]; #!E`%'
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} &n6L;y-
} E0/>E
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publicint getNextIndex(){ u})*6 l.
int nextIndex = getStartIndex() + mln4Vl(l2M
(>E/C^Tc%
pageSize; IaQm)"Z
if(nextIndex >= totalCount) ({@"{
return getStartIndex(); 5D2mZ/
else 5gV,^[E-z
return nextIndex; DBG0)=SHy
} v9FR
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publicint getPreviousIndex(){ ."gq[0_YS
int previousIndex = getStartIndex() - j}d):3!
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pageSize; wEwRW
if(previousIndex < 0) *C0a,G4
return0; 8EMBqhl
else cvo+{u$s
return previousIndex; K F_Uu
} Thu_`QP^
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} $MGKGWx@E
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抽象业务类 ;Z`a[\i':
java代码: :3XvHL0rx
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/** F_g(}wE#
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* Created on 2005-7-12 ]n>9(Mp!M
*/ yz!L:1DG
package com.javaeye.common.business; 2wnk~URj
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import java.io.Serializable; pdER#7Tq
import java.util.List; 65JG#^)KaX
*0Z6H-Do,
import org.hibernate.Criteria; 3 !8#wn
import org.hibernate.HibernateException; f0Q! lMv
import org.hibernate.Session; AZE%fOG<i
import org.hibernate.criterion.DetachedCriteria; )Ute
import org.hibernate.criterion.Projections; kr|r-N`
import ;?@Rq"*
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org.springframework.orm.hibernate3.HibernateCallback; !/tV}.*
import g!'
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y9]7LETv\M
org.springframework.orm.hibernate3.support.HibernateDaoS |bSAn*6b
{D^
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upport; ULu@"
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import com.javaeye.common.util.PaginationSupport; 5Za<]qxr
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public abstract class AbstractManager extends 5%(whSKZF
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HibernateDaoSupport { `7y3C\zyQ
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privateboolean cacheQueries = false; <9"@<[[,
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privateString queryCacheRegion; %'h:G
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publicvoid setCacheQueries(boolean T^v o9~N*
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cacheQueries){ {d'B._#i
this.cacheQueries = cacheQueries; 4[gbRn'
} OmZZTeGg1s
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publicvoid setQueryCacheRegion(String 0sKoNzE
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queryCacheRegion){ dc4XX5Z
this.queryCacheRegion = aM1WC 'c&)
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queryCacheRegion; 3!@&7@p
} #y7 MB6-
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publicvoid save(finalObject entity){ RA!m,"RM
getHibernateTemplate().save(entity); qGR1$\]
} m*HUT V
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publicvoid persist(finalObject entity){ UtJfO`m9P
getHibernateTemplate().save(entity); A{B$$7%
} e 2NF.
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publicvoid update(finalObject entity){ +h/OQ]`/m
getHibernateTemplate().update(entity); Ksh[I,+N\
} ]j,o!|rx7
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publicvoid delete(finalObject entity){ SeS ZMv
getHibernateTemplate().delete(entity); *c/| /
} % rnRy<9
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publicObject load(finalClass entity, >7X5/z
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finalSerializable id){ .,(x7?
return getHibernateTemplate().load i$3#/*Y7_L
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9
(entity, id); 8KigGhY'ms
} +/%4E %
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publicObject get(finalClass entity, MFO%F) 5
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finalSerializable id){ 5N6R%2,A
return getHibernateTemplate().get Z ]ZUK
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(entity, id); WdC7CK
} f>mEX='w
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publicList findAll(finalClass entity){ 5syzh
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return getHibernateTemplate().find("from ASMItT
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" + entity.getName()); PIFZ '6gn
} s5{H15
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publicList findByNamedQuery(finalString j!Ys/D
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namedQuery){ SJj_e-
return getHibernateTemplate #=Xa(<t
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().findByNamedQuery(namedQuery); >b3IZ^SB#$
} >dF #1
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publicList findByNamedQuery(finalString query, OEbZs-:
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finalObject parameter){ X3gYe-2
return getHibernateTemplate X%iqve"{nB
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().findByNamedQuery(query, parameter); R*LPwJuv
} a04S&ezj
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publicList findByNamedQuery(finalString query, }l]r-
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finalObject[] parameters){ E6G;fPd= E
return getHibernateTemplate ]>sMu]biH
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().findByNamedQuery(query, parameters); Y%]g,mG
} 6~s{HI!
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publicList find(finalString query){ MfLus40;n
return getHibernateTemplate().find l{ fL~O
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(query);
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} M5`m5qc3
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publicList find(finalString query, finalObject 6w{""K.{
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parameter){ X88I|Z'HIh
return getHibernateTemplate().find 5/m*Lc+r
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(query, parameter); Z$YG'p{S
} {Y]3t9!\
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public PaginationSupport findPageByCriteria _A]~`/0;`
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria l`JKQk
"6?Y$y/wm
(detachedCriteria, PaginationSupport.PAGESIZE, 0); rHjR 4q
} F>@z&a}(
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public PaginationSupport findPageByCriteria 4HXNu, T'
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(final DetachedCriteria detachedCriteria, finalint 2@ZuH^qhk
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startIndex){ W$" >\A0%
return findPageByCriteria )@.ODW;`
@
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(detachedCriteria, PaginationSupport.PAGESIZE, XT==N-5,
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startIndex); SS,'mv
} c/3]M>+M
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public PaginationSupport findPageByCriteria ooYs0/,{
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(final DetachedCriteria detachedCriteria, finalint .M\0+,%/
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pageSize, =&U7:u
finalint startIndex){ VN@ZYSs
return(PaginationSupport) R*O6Z"h
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getHibernateTemplate().execute(new HibernateCallback(){ uC`)?f*I
publicObject doInHibernate "r{
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(Session session)throws HibernateException { O}Do4>02
Criteria criteria = cC,gd\}M
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detachedCriteria.getExecutableCriteria(session); 9>5]y}.{
int totalCount = E|B1h!!\c
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((Integer) criteria.setProjection(Projections.rowCount =1F F2#zS
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()).uniqueResult()).intValue(); ou&7v<)x4
criteria.setProjection kca Y
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(null); y {Mh ?H
List items = $4TawFf"nc
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criteria.setFirstResult(startIndex).setMaxResults Nx(y_.I{K
f^XfI H_#
(pageSize).list(); =Sn!'@%U]
PaginationSupport ps = F8Z6Ss|v3
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new PaginationSupport(items, totalCount, pageSize, z* :.maq
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startIndex); %5bN@XD
return ps; ]p~,C*UH0
} &T-udgR9
}, true); m=IA/HOR^
} \RTX fe-`
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public List findAllByCriteria(final 9hs7B!3pc>
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DetachedCriteria detachedCriteria){ z#|tl/aP9
return(List) getHibernateTemplate ;,LlOR
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().execute(new HibernateCallback(){ gLv";"4S
publicObject doInHibernate wsfn>w?!V
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(Session session)throws HibernateException { ^S`c-N
Criteria criteria = Ibl==Irk
j6$_U@)%O
detachedCriteria.getExecutableCriteria(session); b*qC
return criteria.list(); K<tkNWasQ
} 8DNGqaH;dt
}, true); *,__\/U98
} ~ +z'pK~c
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public int getCountByCriteria(final [ 5kaF"
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DetachedCriteria detachedCriteria){ ag$UNV
Integer count = (Integer) lV !@h}mG
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getHibernateTemplate().execute(new HibernateCallback(){ s"]LQM1|
publicObject doInHibernate ;-65~i0Iu
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(Session session)throws HibernateException { 7J2i /m
Criteria criteria = g8w5X!Z
b$ )XS
detachedCriteria.getExecutableCriteria(session); ?en%m|}0
return <:BhV82l
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criteria.setProjection(Projections.rowCount E>?T<!r~j
m)?cXM
()).uniqueResult(); eJ!a8
} D8Vb@5MW
}, true); tpi63<N
return count.intValue(); "n@=.x
} iP JZ%
} ve /Q6j{
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用户在web层构造查询条件detachedCriteria,和可选的 yeNC-U<
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 # 1,(I
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PaginationSupport的实例ps。 4o2C=?@(
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ps.getItems()得到已分页好的结果集 `W[oLQ
ps.getIndexes()得到分页索引的数组 wLC|mByq
ps.getTotalCount()得到总结果数 A`Bg"k:D
ps.getStartIndex()当前分页索引 .HG0%Vp
ps.getNextIndex()下一页索引 ,Tyh._sa
ps.getPreviousIndex()上一页索引 ~Hs a6F&F
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _A\c 6#
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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 7@Qz
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一下代码重构了。 z6R<*$4
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我把原本我的做法也提供出来供大家讨论吧: u U>Bun
X(#G6KeZFZ
首先,为了实现分页查询,我封装了一个Page类: @$;"nVZ4v
java代码: M(S:&GOU
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/*Created on 2005-4-14*/ m`-{ V<(M
package org.flyware.util.page; d7tH~9GX8
c X553&
/** C
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* @author Joa i3>7R'q>
* qGgT<Rd~1
*/ Zcv1%hI
publicclass Page { e?G] fz
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/** imply if the page has previous page */ g(MeCoCc
privateboolean hasPrePage; 6P!M+PO
dM 7-,9Vc
/** imply if the page has next page */ Vo"\nj
privateboolean hasNextPage; \ey3i((L
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/** the number of every page */ +B%ZB9
privateint everyPage; nYMdYt04sl
^'C1VQ%
/** the total page number */ ;
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privateint totalPage; )}7rM6hv
}S$]MY,*
/** the number of current page */ Wgdij11e
privateint currentPage; j#0@%d
&B7X LO[
/** the begin index of the records by the current uQ{ &x6.1
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query */ hn-9l1~!h
privateint beginIndex; TgVvp0F;
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/** The default constructor */ "wT[LA9\
public Page(){ $GYcZN&
ep Eg6
} W)?B{\
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/** construct the page by everyPage _bn*B$
* @param everyPage p^A9iieHp=
* */ 4r5?C;g
public Page(int everyPage){ zN {'@B
this.everyPage = everyPage; gz-}nCSi
} < ppg$;
> c?Z.of
/** The whole constructor */ F%t`dz!L
public Page(boolean hasPrePage, boolean hasNextPage, r+;op_
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DnP>ed"M!
int everyPage, int totalPage, a&p|>,WS
int currentPage, int beginIndex){ j}'spKxu
this.hasPrePage = hasPrePage; 5EIh5Y EU>
this.hasNextPage = hasNextPage; ^c!"*L0E
this.everyPage = everyPage; (5re'Pl
this.totalPage = totalPage; &hEtVkK
this.currentPage = currentPage; 7g cr$&+e
this.beginIndex = beginIndex; JVFn=Mw
} _1f!9ghT\
?A;x%8}
/** [ K;3Qf)
* @return Tz]t.]!&E
* Returns the beginIndex. yNP
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*/ Z~ VOO7|m
publicint getBeginIndex(){ 3@*J=LGhKc
return beginIndex; ^i2W=A'P
} tpO%)*
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/** %%}U
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* @param beginIndex %vDN{%h8
* The beginIndex to set. aRdzXq#x
*/ |vw0:\/H
publicvoid setBeginIndex(int beginIndex){ &aqF||v%)
this.beginIndex = beginIndex; D|@*HX@_Xp
} G<l+94(
Jc"xH~,
/** N2vSJ\u
* @return iF?4G^
* Returns the currentPage. \L-o>O
*/ eYMp@Cx
publicint getCurrentPage(){ /\V-1 7-
return currentPage; (PE x<r1
} 8hZ+[E}
@-Tt<pl'L
/** 6Lr G+p`
* @param currentPage 1WRQjT=o
* The currentPage to set. a.#`>
*/ E4GtJ`{X
publicvoid setCurrentPage(int currentPage){ Cb5;l~}L
this.currentPage = currentPage; {M96jjiInf
} /qa{*"2Qo
N?TXPY
/** lO! Yl:;m%
* @return ]*|+06
* Returns the everyPage. (B{`In8G>y
*/ \C $LjSS-
publicint getEveryPage(){ oOlqlv
return everyPage; _]@
} sa$CCQ
8i/5L=a"`
/** '/%]B@!
* @param everyPage zgXg-cr
* The everyPage to set. 4t]ccqX*{
*/ 'hN_H}U
publicvoid setEveryPage(int everyPage){ mN?y\GB
this.everyPage = everyPage; N"1o>
!
} 6e0tA ()F
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/** L_3Ao'SA
* @return $L7Z_JD5
* Returns the hasNextPage. k ! l\|~
*/ tBC`(7E}
publicboolean getHasNextPage(){ oJb${k<3
return hasNextPage; \H^DiF%f9
} r==d^
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g
/** <ZO"0oz%
* @param hasNextPage Vea2 oQq
* The hasNextPage to set. 5]pvHc
*/ #@FMH*?xX6
publicvoid setHasNextPage(boolean hasNextPage){ Z0HfrK#oU
this.hasNextPage = hasNextPage; =?]H`T:
} BdBwfH%:
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/** Cw6\'p%l-\
* @return 0M=A,`qk
* Returns the hasPrePage. ybNo`:8A;
*/ Yuo:hF\DH
publicboolean getHasPrePage(){ E><$sN6
return hasPrePage; {\zTE1X9
} 3/_rbPr
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/** C.qNBl*
* @param hasPrePage 'D_a2xo0
* The hasPrePage to set. =rz7 x
*/ IAyyRl\
publicvoid setHasPrePage(boolean hasPrePage){ #&0G$~
this.hasPrePage = hasPrePage; 3v\69s
} dRj2%Q f
: EA-L
/** <@:RS$"i
* @return Returns the totalPage. FQY{[QvF~
* 4JQd/;
*/ 0V;9v
publicint getTotalPage(){ 8Of.n7{
return totalPage; vH1IVF"DS
} ^UU@7cSi|G
B xAyjA6
/** {A^ 3<=|
* @param totalPage K0;caqE^
* The totalPage to set. +4L]Z;k
*/ #aI(fQZe
publicvoid setTotalPage(int totalPage){ rhff8C//'
this.totalPage = totalPage; 1 S<E=7
} 5@QJ+@j|
F*u"LTH
} p^.qwP\P
z)tULnR8
df\ ^uyD;
^^
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2P35#QI[)
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 2i9FzpC3
V.w
L
个PageUtil,负责对Page对象进行构造: jk(tw-B
java代码: ?+)>JvWDz
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/*Created on 2005-4-14*/ ;Mw<{X-
package org.flyware.util.page; Ms<v81z5T
79&=MTM
import org.apache.commons.logging.Log; C#qF&n
import org.apache.commons.logging.LogFactory; i.Rxx, *?
pyUzHF0
/** Fs$mLa
* @author Joa B:)PUBb
* P5Bva
*/ G*s5GG@Z.
publicclass PageUtil { SI`ems{1>c
vVhSl$mW
privatestaticfinal Log logger = LogFactory.getLog ^O0trM>h-
@`mr|-Rp@
(PageUtil.class); J]W?
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/** L;\f^v(
* Use the origin page to create a new page ]ZR}Pm/CA
* @param page dzk1 !yy
* @param totalRecords /07iQcT(
* @return mX2X.ww(4
*/ jXPf}{^
publicstatic Page createPage(Page page, int
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cqYMzS
t
totalRecords){ ^O.` P
return createPage(page.getEveryPage(), 4Sz2
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9y'To JZ6
page.getCurrentPage(), totalRecords); _|r/*(hh
} "]T1DG"
a#D \8;
/** sWyx_
* the basic page utils not including exception F4NMq&_
'QSj-
handler =Q,D3F
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* @param everyPage _U|rTil
* @param currentPage D dh
* @param totalRecords \J(kevX
* @return page _TwEym.V
*/ &8;Fi2}(L
publicstatic Page createPage(int everyPage, int /z
m+
w-];!;%
currentPage, int totalRecords){ h e=A%s
everyPage = getEveryPage(everyPage); [jz@d\k$_
currentPage = getCurrentPage(currentPage); HQZJK82
int beginIndex = getBeginIndex(everyPage, wZ5k|5KtW
HCKoc L/]h
currentPage); j];#=+
int totalPage = getTotalPage(everyPage, EG8%X "p
ZU$QwI8
totalRecords); ep6V2R
boolean hasNextPage = hasNextPage(currentPage, 18^K!:Of
wG&Z7C b
totalPage); |w"G4J6ha
boolean hasPrePage = hasPrePage(currentPage); =}"P;4:
nt%fJ k
returnnew Page(hasPrePage, hasNextPage, !a4`SjOgu
everyPage, totalPage, a|5<L
currentPage, O]XgA0]
T|&u?
beginIndex); PYwGGB-
} :IO"' b
lDL(,ZZS`
privatestaticint getEveryPage(int everyPage){ ~\*wt( o
return everyPage == 0 ? 10 : everyPage; ef@F!s_fI
} +4n}H}9l
>]HvXEdNZ|
privatestaticint getCurrentPage(int currentPage){ ta@fNS4
return currentPage == 0 ? 1 : currentPage; Sim$:5P
} R2==<"gq
dy ~M5,zn
privatestaticint getBeginIndex(int everyPage, int q>s`G
z5_jx&^Z
currentPage){ \j<aFOT(
return(currentPage - 1) * everyPage; ujn7DBE"
} 6P
T)
a$EudD#+
privatestaticint getTotalPage(int everyPage, int r]'[qaP
]5Q)mWF
totalRecords){ nf-6[dg
int totalPage = 0; Y>{%,d#s_
E#A}2|7,g
if(totalRecords % everyPage == 0) [s+FX5' K
totalPage = totalRecords / everyPage; :j#zn~7
else 6FX]b4
totalPage = totalRecords / everyPage + 1 ; (tF/2cZk
|kF"p~s
return totalPage; 5s%FHa
} 2J Wp5
R|k!w]
privatestaticboolean hasPrePage(int currentPage){ J|@O4g
return currentPage == 1 ? false : true; )h]tKYx
} f[*g8p
#3O$B*gV6
privatestaticboolean hasNextPage(int currentPage, &gP1=P,!
;Za^).=
int totalPage){ sHPlNwyy
return currentPage == totalPage || totalPage == lmIphOUoIw
u`XZtF<vf
0 ? false : true; gk}.LE
} LWxP}? =
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&Z}}9dd
} pf#R]
Abpzf\F
4<- E0
l}FA&c"
W6)XMl}n
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。 x&N@R?AG1
m;sYg
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 P@<K&S+f
" ;o,D
做法如下: @7sHFwtar?
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,D.@6bJW
iA4VT,
的信息,和一个结果集List: .B!L+M< [
java代码: 3!Mb<W.3
- v=ndJ.
KhPDXY]!
/*Created on 2005-6-13*/ %+dRjG~TB
package com.adt.bo; 6|Crc$4l
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import java.util.List; BPy pA$
AY]rQ:I
import org.flyware.util.page.Page; )LL.fPic
;`Sn66&
/** ?U,Xy xN
* @author Joa yn2k!2]&T<
*/ m~@Lt~LZs
publicclass Result { tbB.n
YCBUc<)
private Page page; >qdRqy)DC
+p-S36K~,7
private List content; yg%T{hyzH
(OG>=h8?
/** CbMClnF
* The default constructor $cGV)[KWp@
*/ O_D;_v6Ii+
public Result(){ _z3^.QP
super(); ^Uldyv/
} K&&YxX~3
]2z
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/** NV^n}]ci
* The constructor using fields K14{c1
* 602=qb
* @param page 5?TjuGc
* @param content %G jjl*`E
*/ ks8x xY
public Result(Page page, List content){ F '55BY*!
this.page = page; ([ hd
this.content = content; |H8UT SX+
} r+nhm"9
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/** 0[s<!k9=
* @return Returns the content. D|8h^*Ya
*/ z.:IUm{z
publicList getContent(){ U}W7[f lc
return content; C2?p>S/q
} h-@_.&P0e
a{iG0T.{Yh
/** B 3eNvUFZg
* @return Returns the page. L_AQS9a^D
*/ y|%lw%cSe
public Page getPage(){ &wB?ks
return page; &&n-$WEl
} M5B?`mTl
.Tc?9X~4
/** }}v28"\TA
* @param content g@S?5S.Av
* The content to set. cs)z!
*/ p B79#4
public void setContent(List content){ I\VC2U
this.content = content; T( bFn?
} I=V]_Ik4N
RTYhgq
/** x;/%`gKn8
* @param page r)Iq47Uiw
* The page to set. ?E7.x%n7X5
*/ [M:BJ%*
publicvoid setPage(Page page){ D^2yP~(
this.page = page; MtK5>mhZI`
} =A^VzIj(
} 0Yc#fD
6H!"oC&
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TGozoPV
@RS|}M^4
2. 编写业务逻辑接口,并实现它(UserManager, yl~h
`b4
$g)X,iQu
UserManagerImpl) qgsKbsl
java代码: a.g:yWL\
-\fn \n
}MV=t7x9+
/*Created on 2005-7-15*/ rxAb]~MMp
package com.adt.service; n5 jzVv
y:8Oc?
import net.sf.hibernate.HibernateException; z,=k F I
mdIa`OZr
import org.flyware.util.page.Page; `@i!'h
@&]%%o+
import com.adt.bo.Result; '|K408i
~D\ V!
/** :S{+|4pH
* @author Joa nK|WzUtp
*/ ZIM 5$JdCv
publicinterface UserManager { ?!kPW^gD
]+i~Cbj
public Result listUser(Page page)throws i^DZK&B@u
{KalVZX2R
HibernateException; SgPvQ'\
EXYr_$gRs
} W%cJ#R[o
Zae$M0)
HWT^u$a"
XqTDLM&
E:ocx2dp
java代码: =
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AIFI@#3
/*Created on 2005-7-15*/ /0qLMlL$
package com.adt.service.impl; B@2VI
1%
>~k"C,6
import java.util.List; Kdwt^8Umh
X
Sw0t8
import net.sf.hibernate.HibernateException; 2N:|B O>
cp>1b8l6?
import org.flyware.util.page.Page; /__@a&9t
import org.flyware.util.page.PageUtil; k\a&4v
JA~v:ec
import com.adt.bo.Result; X,8]g.<
import com.adt.dao.UserDAO; :;]iUjiC8
import com.adt.exception.ObjectNotFoundException; cfd7)(6
import com.adt.service.UserManager; T#e ;$\
/a!M6:,pX
/** i>68gfx
* @author Joa .0>2j(
*/ ,P9q[
publicclass UserManagerImpl implements UserManager { \P|PAU@,
G\1\L*+0
private UserDAO userDAO; B#K{Y$!v
u:f.g?!`"
/** 7U\GX
* @param userDAO The userDAO to set. G>);8T%l
*/ nuip
publicvoid setUserDAO(UserDAO userDAO){ L^0s
this.userDAO = userDAO; X)peY
} '{?7\+o.x
69$[yt>KYz
/* (non-Javadoc) 8vLaSZ="[
* @see com.adt.service.UserManager#listUser Yq?FiE0
VgO:`bDF
(org.flyware.util.page.Page) @H^Yf
*/ ?@i_\<A2
public Result listUser(Page page)throws ]FNqNZ
$ RDwy)9
HibernateException, ObjectNotFoundException { x2bKFJ>e@
int totalRecords = userDAO.getUserCount(); JXIxk"m
if(totalRecords == 0) $kA'9Y
throw new ObjectNotFoundException cn$o$:tW
-6OgM}
("userNotExist"); +(-L
page = PageUtil.createPage(page, totalRecords); ZCAdCKX|
List users = userDAO.getUserByPage(page); kgV_*0^
returnnew Result(page, users); eJJD'Z
} x$;I E
_Fz]QxO
} 7xIXFuu
1]i{b/ 4
bZ$;`F5})
dyz)22{\!`
=-e`OHA
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Pu=,L#+F N
{m)$ b
询,接下来编写UserDAO的代码: 5HZ t5="+
3. UserDAO 和 UserDAOImpl: .MzVc42<
java代码: hv.$p5UY*
\Y0o~JD
? %9-5"U[
/*Created on 2005-7-15*/ AUm"^-@x#>
package com.adt.dao; c05kHB$O
oK5"RW
import java.util.List; ([r4N#lx
8tR(i[L
import org.flyware.util.page.Page; <