Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 qC.jXU?rO
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?ti7iBz?
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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 |@Q(~[It
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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 4x e:+sA.N
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分页支持类: !*?&V3!
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java代码: 3=T<c?[
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package com.javaeye.common.util; w v9s{I{P
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import java.util.List; ~9h6"0K!
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publicclass PaginationSupport { 2"yzrwZ:
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publicfinalstaticint PAGESIZE = 30; n_.2B$JD
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privateint pageSize = PAGESIZE; s2b!Nib
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privateList items; @<W"$_r-
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privateint totalCount; \
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privateint[] indexes = newint[0]; K)l{3\9l|
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privateint startIndex = 0; F@"Xd9q?
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public PaginationSupport(List items, int IOvYvFUUJ
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totalCount){ y !47!Dn
setPageSize(PAGESIZE); k[A=:H1"
setTotalCount(totalCount); R:0Fv9bwS
setItems(items); "EWU:9\0
setStartIndex(0); vb{&T<
} i ,4
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public PaginationSupport(List items, int { tim{nV
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totalCount, int startIndex){ gigDrf}
setPageSize(PAGESIZE); T/)$}#w0i
setTotalCount(totalCount); i3rvDch
setItems(items); =f.f%g6
setStartIndex(startIndex); JEU?@J71O
} E)#3*Wlu$
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public PaginationSupport(List items, int K&D
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totalCount, int pageSize, int startIndex){ F!c%&Z
setPageSize(pageSize); xO"5bj
setTotalCount(totalCount); i*9eU*i|H
setItems(items); s-*8=
setStartIndex(startIndex); czdNqk.kh
} o=w&&B
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publicList getItems(){ wvx
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return items; &>i+2c~
} {LR?#.
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publicvoid setItems(List items){ NZi5rXN
this.items = items; - FA#hUK$
} qB<D'h7
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o
publicint getPageSize(){ S%mN6b~{
return pageSize; +]`MdOu
} _BHb0zeot
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publicvoid setPageSize(int pageSize){ ;=F^G?p^
this.pageSize = pageSize; )nQpO"+M
} :*A6Ba
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publicint getTotalCount(){ 3::DURkjf
return totalCount; wH{lp/
} ^[\F uSL
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publicvoid setTotalCount(int totalCount){ Gob1V
if(totalCount > 0){ _9\ayR>d
this.totalCount = totalCount; Ks8S^77
int count = totalCount / tA}O'x
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pageSize; .OXvv _?<
if(totalCount % pageSize > 0) 1UyI.U]
count++; *oZBv4Vh
indexes = newint[count]; `Qaw]&O
for(int i = 0; i < count; i++){ 5a5I+*
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indexes = pageSize * 8yB
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i; 3MNo&0M9
} f{^C+t{r
}else{ "eZNci
this.totalCount = 0; }yx'U 3
} [=S@lURzm@
} h+t{z"Ic=
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publicint[] getIndexes(){ g[q1P:I@W
return indexes; r,L#JR w#-
} aoI{<,(
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publicvoid setIndexes(int[] indexes){ "Z& {
this.indexes = indexes; efl6U/'Ij
} "9&6bBa
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publicint getStartIndex(){ m~(]\
return startIndex; #wk'&XsC#z
} F1w~f
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publicvoid setStartIndex(int startIndex){ `GqS.O}C
if(totalCount <= 0) .Rd@,3
this.startIndex = 0; TPvS+_<oL{
elseif(startIndex >= totalCount) b@/z^k{%
this.startIndex = indexes #gUM%$
R1{"
[indexes.length - 1]; M_Z*F!al<
elseif(startIndex < 0) FC.y%P,
this.startIndex = 0; do+HPnfDzU
else{ FxTOc@<
this.startIndex = indexes Yvs9)g
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[startIndex / pageSize]; vz#rbBY*;
} .NiPaUzc<
} IgG@v9'
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publicint getNextIndex(){ WG1UvPK
int nextIndex = getStartIndex() + zY bSv~)
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pageSize; U~s&}M\n
if(nextIndex >= totalCount) z<m,Xj4w
return getStartIndex(); L/"u,~[
else \T/~"
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return nextIndex; 4IG'Tm
} /H: '(W_b;
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publicint getPreviousIndex(){ @Vr?)_0
int previousIndex = getStartIndex() - Hh(_sewo
/=FQ{tLr
pageSize; "6gu6f
if(previousIndex < 0) )z=`,\&p:
return0; S=0zP36kH:
else ;k9s@e#a
return previousIndex; V=H87^b
} sc@v\J;k
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} :cnH@:
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抽象业务类 E@}t1!E<
java代码: erdWGUfQOe
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/** %A,4vLe~6
* Created on 2005-7-12 l-Xxur5M'
*/ pfe9n[
package com.javaeye.common.business; &y;('w
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import java.io.Serializable; _SJ#k|vcq
import java.util.List; u `1cXL['
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import org.hibernate.Criteria; aW$sd)
import org.hibernate.HibernateException; +Tf ,2?O
import org.hibernate.Session; razVO]]E
import org.hibernate.criterion.DetachedCriteria; x\]%TTps
import org.hibernate.criterion.Projections; ;$ D*,W
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import G +o)s
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org.springframework.orm.hibernate3.HibernateCallback; V2W)%c'
import s(w6Ldi
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org.springframework.orm.hibernate3.support.HibernateDaoS }oIA*:5
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upport; >)YaWcI
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import com.javaeye.common.util.PaginationSupport; U;<07
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public abstract class AbstractManager extends X-|Lg.s
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HibernateDaoSupport { ~e~iCyW;S
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privateboolean cacheQueries = false; YDE;mIW
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privateString queryCacheRegion; f7c%Z:C#Y
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publicvoid setCacheQueries(boolean I,OEor6%R(
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cacheQueries){ ;HtHN
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this.cacheQueries = cacheQueries; "a
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} Lt$LXE
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publicvoid setQueryCacheRegion(String GLrHb3@"N
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queryCacheRegion){ PzbLbH8A
this.queryCacheRegion = -\O%f)R
} QVREj
queryCacheRegion; &sleV5V
} atRWKsY<
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publicvoid save(finalObject entity){ 6}zargu(;
getHibernateTemplate().save(entity); .\ K0+b;
} bBA
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publicvoid persist(finalObject entity){ b2]1Dfw
getHibernateTemplate().save(entity); OPHf9T3H
} >|Ps23J#
@(Q'J`
publicvoid update(finalObject entity){ N) D;)ZH
getHibernateTemplate().update(entity); 4d~Sn81xW
} P/uk]5H^
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publicvoid delete(finalObject entity){ \@8j&],dl
getHibernateTemplate().delete(entity); ,U':=8
} "l0z?u
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publicObject load(finalClass entity, faH113nc
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finalSerializable id){
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return getHibernateTemplate().load sTeW4Hnp
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(entity, id); B=?4; l7
} E{+V_.tlu
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publicObject get(finalClass entity, (ns>z7
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finalSerializable id){ %6c[\ubr
return getHibernateTemplate().get Qxb5Y)/jn
q {v?2v{
(entity, id); 0G@sj7)]
} kex4U6&OQB
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publicList findAll(finalClass entity){ B+W 4r9#
return getHibernateTemplate().find("from a?&{eMEe}
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" + entity.getName()); P")duv
} HjG!pO{
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publicList findByNamedQuery(finalString `x%(
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namedQuery){ Npu#.)G
return getHibernateTemplate o\ss
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().findByNamedQuery(namedQuery); H#yBWvj*H
} Qy!*U%tG'
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publicList findByNamedQuery(finalString query, &,vPZ,7l
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finalObject parameter){ doeYc
return getHibernateTemplate E=PmOw7b
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().findByNamedQuery(query, parameter); dS9L( &
} ean_/E
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publicList findByNamedQuery(finalString query, A}K2"lQ#>,
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finalObject[] parameters){ ~cHpA;x9<^
return getHibernateTemplate ! 2]eVO
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().findByNamedQuery(query, parameters); +OGa}9j-
} rK^Sn7 U
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publicList find(finalString query){ 7;]n+QRfm
return getHibernateTemplate().find i{1SUx+Re
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(query); 3RSiu}
} PWU8 9YXp
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publicList find(finalString query, finalObject Na6z1&wS
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parameter){ Q[5j5vry
return getHibernateTemplate().find TV^m1uC
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(query, parameter); A}./ ;[
} \J@i:J6x$1
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public PaginationSupport findPageByCriteria WX2:c,%:
ey icMy`7{
(final DetachedCriteria detachedCriteria){ 5G$sP,n
return findPageByCriteria QOb+6qy:3
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); `TugtzRU
} +@n8DM{b
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public PaginationSupport findPageByCriteria J`uO~W"
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(final DetachedCriteria detachedCriteria, finalint m6'VMW
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startIndex){ 12W`7
return findPageByCriteria \U(;%V
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(detachedCriteria, PaginationSupport.PAGESIZE, Etv!:\\[
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startIndex); -eZ$wn![
} >a6{y
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public PaginationSupport findPageByCriteria =IbDGw(
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(final DetachedCriteria detachedCriteria, finalint U^AywE]
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pageSize, xK7xAO
finalint startIndex){ 4F WL\;6
return(PaginationSupport) 701mf1a
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getHibernateTemplate().execute(new HibernateCallback(){ 6a_MA*XK
publicObject doInHibernate .?<M$38fv
@/(\YzQvp]
(Session session)throws HibernateException { H>zX8qP+
Criteria criteria = n\X'2
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detachedCriteria.getExecutableCriteria(session); nU^ -D1s{
int totalCount = Jf#Ika&px
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((Integer) criteria.setProjection(Projections.rowCount %9^^X6yLM
>
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()).uniqueResult()).intValue(); ^(w%m#
criteria.setProjection 5uo?KSX%
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(null); H K]-QTEn
List items = F!N D
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criteria.setFirstResult(startIndex).setMaxResults 6"OwrJB
\B72 #NR
(pageSize).list(); .dbZ;`s
PaginationSupport ps = %S'gDCwq
0.MD_s0)>
new PaginationSupport(items, totalCount, pageSize, IjshxNk
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startIndex); nM=5L:d
return ps; s *8)|N
} w)nFH)f
}, true); 5c8tH=
} Ci?BJ,
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public List findAllByCriteria(final 4@qHS0$
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DetachedCriteria detachedCriteria){ sf7~hN*
return(List) getHibernateTemplate Fj_6jsDb
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().execute(new HibernateCallback(){ %ZKP d8
publicObject doInHibernate 2aDjt{7P
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(Session session)throws HibernateException { 7I#<w[l>k
Criteria criteria = aa-{,X"MF
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detachedCriteria.getExecutableCriteria(session); >e'Hz (~'/
return criteria.list(); )o=ipm[
} E]aQK.
}, true); ?KB+2]7m6
} uG\ @e'pr
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public int getCountByCriteria(final 006qj.
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DetachedCriteria detachedCriteria){ EuJ_UxkG
Integer count = (Integer) 8LPvb#9=
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getHibernateTemplate().execute(new HibernateCallback(){ 6_&uYA<8pE
publicObject doInHibernate VB}4#-dG?
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(Session session)throws HibernateException { f4mQDRlD
Criteria criteria = aSGZF w
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detachedCriteria.getExecutableCriteria(session); yPn!1=-(
return B$\,l.hE
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criteria.setProjection(Projections.rowCount o/J2BZ<_<
K6z)&<
()).uniqueResult(); h1_9Xp~N
} 8kRqF?rbj
}, true); {:%A
return count.intValue(); "p"M9P'
} !gyEw1Re7
} ?=},%^
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用户在web层构造查询条件detachedCriteria,和可选的 rGqT[~{t
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4WAs_~
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PaginationSupport的实例ps。 ES>iM)M
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ps.getItems()得到已分页好的结果集 x%`.L6rj
ps.getIndexes()得到分页索引的数组 \F; S
ps.getTotalCount()得到总结果数 5bZjW~d
ps.getStartIndex()当前分页索引 e,X{.NS
ps.getNextIndex()下一页索引 yu.N> [=
ps.getPreviousIndex()上一页索引 ir?Y>
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Kqn{q4L
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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 RAs5<US:
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一下代码重构了。 ;;]^d_
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我把原本我的做法也提供出来供大家讨论吧: QqdVN3#1z
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首先,为了实现分页查询,我封装了一个Page类: Y@#rGV>
java代码: >39\u&)
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/*Created on 2005-4-14*/ k3-7Vyg
package org.flyware.util.page; .~C[D
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/** !]l!I9
* @author Joa $j"TPkW{M
* qJZ:\u8oO
*/ bkSI1m3
publicclass Page { W*!u_]K>
!C>'a:
/** imply if the page has previous page */ >&-"
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privateboolean hasPrePage; }|-Yd"$
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/** imply if the page has next page */ Eo@b)h
privateboolean hasNextPage; CW .
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/** the number of every page */ j-n-2:Q
privateint everyPage; 8)m
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/** the total page number */ {{+woL'C
privateint totalPage; WvVf+|Km
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/** the number of current page */ a(|,KWHn
privateint currentPage; SJd,l,Gg)
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/** the begin index of the records by the current cq,8^o&
cpJ(77e
query */ zjlo3=FQX[
privateint beginIndex; rD*CLqK
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/** The default constructor */ _rIFwT1]
public Page(){ OLh QS_D
j%TcW!D-_
} 7TaHE
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/** construct the page by everyPage "i1r9TLc
* @param everyPage nLjc.Z\Bl
* */ fo$Ac
public Page(int everyPage){ LE>b_gQ$
2
this.everyPage = everyPage; TxDzGC
} lRr ={
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/** The whole constructor */ P+s-{vv{0
public Page(boolean hasPrePage, boolean hasNextPage, NUjo5.7
??g `c=R!V
Ix1[ $9
int everyPage, int totalPage, 7$/%c{o
int currentPage, int beginIndex){ \}9GK`oR
this.hasPrePage = hasPrePage; ~K-_]*[x
this.hasNextPage = hasNextPage; [pgld9To
this.everyPage = everyPage; B(l8&
this.totalPage = totalPage; "<LVA2v;
this.currentPage = currentPage; UW@BAj@^@
this.beginIndex = beginIndex; dLnu\bSF
} 1}>u Y
HaiaDY)
/** }ki}J >j|f
* @return A\S1{JrR
* Returns the beginIndex. MRZ/%OZ.
*/ mok%TK
publicint getBeginIndex(){ U%)m
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return beginIndex; *
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} FaVeP%v
g XThdNU4G
/** o;\c$|TNU
* @param beginIndex 2ij/!
* The beginIndex to set. @w]z"UCwV@
*/ DD(K@M
publicvoid setBeginIndex(int beginIndex){ .dStV6
this.beginIndex = beginIndex; X1GpLy)p
} ++ZtL\h{7
@cT= t0*
/** zbM*/:Y
* @return BMlu>,
* Returns the currentPage. Pcox~U/j
*/ NIasce e
publicint getCurrentPage(){ fNllF,8}
return currentPage; YLO/J2['
} JRT,%;*,
irRe}
/** e9e7_QG_-
* @param currentPage $GcVI;a
* The currentPage to set. JLZ=$ d
*/ LsGu-Y5^
publicvoid setCurrentPage(int currentPage){ G"._]3CPF
this.currentPage = currentPage; tUR9ti
} >QJfTkD$
y7x[noGtR
/** j^&{5s
* @return y5AJ1A6?E
* Returns the everyPage. 8fI&-uP{g
*/ LNR~F_64Q
publicint getEveryPage(){ `OP?[
f d
return everyPage; tm[e?+Iq
} RXDPT
fvUD'sx
/** C"=^(HU
* @param everyPage HvSYE[Zt|
* The everyPage to set. Edi`x5"l
*/ }[%d=NY
publicvoid setEveryPage(int everyPage){ ])YGeY(V0+
this.everyPage = everyPage; m=7Z8@sX},
} vKCgtk
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/** lx vRF93a.
* @return yavoGk
* Returns the hasNextPage. 5?()o}VjAO
*/ 3{;W!/&>
publicboolean getHasNextPage(){ Es~|:$(N]|
return hasNextPage; 5_}e?T&s
} !Ui"<0[,
%j*i=
/** )f6:{ma
* @param hasNextPage l*+5WrOS
* The hasNextPage to set. _P]!J~$5
*/ ZJ7<!?6
publicvoid setHasNextPage(boolean hasNextPage){ xQetAYP`
this.hasNextPage = hasNextPage; ggR--`D[
} .{@aQwN
0/F/U=Z!
/** sivd@7r\Fa
* @return
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* Returns the hasPrePage. ra'h\m
*/ m<cvx3e
publicboolean getHasPrePage(){ I
)LO@
return hasPrePage; +[sZE
X
} @/m|T]'8
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/** H"g$qSx
* @param hasPrePage <e:2DB&
* The hasPrePage to set. KfVLb4@16_
*/ S_B $-H|
publicvoid setHasPrePage(boolean hasPrePage){ tKik)ei
this.hasPrePage = hasPrePage; UI,i2<&
} *Ugtg9j
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/** u?>]C6$
* @return Returns the totalPage. vFL\O
* vj23j[!|
*/ |4F3Gu
publicint getTotalPage(){ kK]^q|vb6
return totalPage; JvZNr?_w%
} Du3nK"-g
HcrI3v|6
/** 8] BOq:
* @param totalPage 71h?t`N
* The totalPage to set. N{(Q,+ ~
*/ f~3_Rv!
publicvoid setTotalPage(int totalPage){ E|aPkq]
this.totalPage = totalPage; ~
}<!ON;
} ^.d97rSm
nsCat($)
} ;BR`}~m
sPee"9%,
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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 'Si1r%'m#
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个PageUtil,负责对Page对象进行构造: aFj)s?$4]K
java代码: BK_x5mGu3
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/*Created on 2005-4-14*/ \(C_t1
package org.flyware.util.page; ]/p)XHKo
p$5+^x'(
import org.apache.commons.logging.Log; r`THOj\cM
import org.apache.commons.logging.LogFactory; j|u6TG
NTHy!y<!h
/** Use`E
* @author Joa Nz,8NM]
* +U%U3tAvs
*/ H@uCbT
publicclass PageUtil { ?}N@bsl08w
zai x_mR
privatestaticfinal Log logger = LogFactory.getLog zlh}8Es
m,~
@1
(PageUtil.class); t^=6czk
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/** (]Z$mv!
* Use the origin page to create a new page 39W6"^q"o
* @param page X:*Ut3"
* @param totalRecords Daa2.*
* @return NC*h7
*/ O^D$ ~
]
publicstatic Page createPage(Page page, int LN8V&'>
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totalRecords){ Om%9 x
return createPage(page.getEveryPage(), +M+ht
;)^eDJ<
page.getCurrentPage(), totalRecords); {I!sXj
} By
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aqjS 5!qh
/** ~$0Qvyb>
* the basic page utils not including exception 0YsC@r47wL
{-sy,EYcw
handler Q1G?e,Q
* @param everyPage He4sP`&I
* @param currentPage uLw$`ihw
* @param totalRecords w,\#)<boyb
* @return page o,!r t1&0
*/ b@OL!?JP
publicstatic Page createPage(int everyPage, int SnF3I
|]5g+sd
currentPage, int totalRecords){ HR85!S`
everyPage = getEveryPage(everyPage); rurC! -
currentPage = getCurrentPage(currentPage); 4s<*rKm~
int beginIndex = getBeginIndex(everyPage, pcM'j#;
d1c_F~h<
currentPage); W*q[f!@
int totalPage = getTotalPage(everyPage, t(4%l4i;X
OBF2?[V~
totalRecords); %bnDxCj"
boolean hasNextPage = hasNextPage(currentPage, '"H'#%RU
P5+FZzQ
totalPage); 0Ts[IHpg&E
boolean hasPrePage = hasPrePage(currentPage); 5@$b@jTd
M]?#]3XBNo
returnnew Page(hasPrePage, hasNextPage, (mvAEN+y
everyPage, totalPage, Bv^{|w
currentPage, Nb[z+V{=
4c2*)x$@
beginIndex); =kq!e
} qA<PF+f
&Bbs\
;
privatestaticint getEveryPage(int everyPage){ a G^kL
return everyPage == 0 ? 10 : everyPage; 54kd>)|"ag
} S6 F28 d[j
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privatestaticint getCurrentPage(int currentPage){ N\IdZX%u
return currentPage == 0 ? 1 : currentPage; )#9R()n!
} 8>TDrpT}
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privatestaticint getBeginIndex(int everyPage, int 9-DDly [)4
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currentPage){ }>cQ}6n.
return(currentPage - 1) * everyPage; sKhX0,s&
} .(tga&]
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privatestaticint getTotalPage(int everyPage, int gqaENU>
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totalRecords){ DWep5$>&K
int totalPage = 0; .~0A*a
(( 0%>HJ{~
if(totalRecords % everyPage == 0) xp%,@]p
totalPage = totalRecords / everyPage; mnM#NT5]
else sgDlT=c'
totalPage = totalRecords / everyPage + 1 ; )TxAhaz+
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return totalPage; CUB= T]
} M3j_sd'N
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privatestaticboolean hasPrePage(int currentPage){ 7p&%0'BO1z
return currentPage == 1 ? false : true; H4 }^6><V
} Ij
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privatestaticboolean hasNextPage(int currentPage, m!s/L,iJJ
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int totalPage){ Pew-6u"
return currentPage == totalPage || totalPage == p]uwGWDI
T~UKWAKX}
0 ? false : true; BlQu9{=n
}
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 m M!H}|
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面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 [G^ir
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做法如下: `#hdb=3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 NrVrR80Y
WC,&p
的信息,和一个结果集List: *upl*zFf0
java代码: 'u$e2^
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/*Created on 2005-6-13*/ MV5'&" ,oB
package com.adt.bo; s{#ZRmc2B
++-\^'&1
import java.util.List; 0n+Wv@/
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import org.flyware.util.page.Page; r#
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/** ,{A-<=6t
* @author Joa bS_!KU
*/ d !
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publicclass Result { [>+(zlK"
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private Page page; f_X]2in
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private List content; >(Jy=m?
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/** S`TP#uzKu]
* The default constructor k.>*!l0
*/ `6`NuZ*6g
public Result(){ ~?8B~l^
super(); dhpEBJ
} #P$=P2o
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/** 7Xm7{`jH
* The constructor using fields w1EYXe
* S P)$K=
* @param page =1fO"|L
* @param content g<O*4
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*/ -Y%#z'^-
public Result(Page page, List content){ {XiBRs e
this.page = page; ncf=S(G+
this.content = content; e&?o
} P9vN5|"M
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/** SeqnO.\
* @return Returns the content. q05_5
*/ @47MJzC
publicList getContent(){ w}^z1n
return content; n.p6+^ES
} AxLnF(eG
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/** B\A2Vm`&
* @return Returns the page. kPF[E5
*/ &}31q`
public Page getPage(){ FqAW><
return page; d9h"Q
} -8; ,#
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/** 2 628 c`
* @param content Fyoy)y*
* The content to set. gE]) z*tqX
*/ J:Uf}!D
public void setContent(List content){ T (]
this.content = content; "knSc0,u
} W+V#z8K
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/** JyWBLi;Z
* @param page r 11:T3
* The page to set. aN{C86wx
*/ Dp!3uR']p
publicvoid setPage(Page page){ '`$a l7D
this.page = page; n}PK0
} .j:[R.
} +ia F$
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2. 编写业务逻辑接口,并实现它(UserManager, ~,KAJ7O_
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UserManagerImpl) j7=I!<w V
java代码: Rq~\Yf+Pm
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w~@.&
/*Created on 2005-7-15*/ 3/mVdU?U
package com.adt.service; QPjmIO
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import net.sf.hibernate.HibernateException; Gjq:-kX\
@gc lks/M
import org.flyware.util.page.Page; oomB/"Z
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import com.adt.bo.Result; X9C)FS
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/** pe=Ou0
* @author Joa Yf
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*/ Bt4
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publicinterface UserManager { w#g0nV"X6
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public Result listUser(Page page)throws ;xaOve;9
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HibernateException; /*s:ehj
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} FDM&rQ
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java代码: pisjfNT`o
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0 ;kcSz
/*Created on 2005-7-15*/ Z)Y--`*
package com.adt.service.impl; -Qx:-,.a
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import java.util.List; } r^@Xh
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import net.sf.hibernate.HibernateException; wOQ-sp0q0
5\1Z"?
import org.flyware.util.page.Page; CZyOAoc<
import org.flyware.util.page.PageUtil; cY?<
W/
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import com.adt.bo.Result; CL%?K<um
import com.adt.dao.UserDAO; /'?Fz*b
import com.adt.exception.ObjectNotFoundException; J&UFP{)
import com.adt.service.UserManager; |1J=wp)#
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/** > ^fY`x,
* @author Joa R<
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*/ e:}8|e~T
publicclass UserManagerImpl implements UserManager { ?P4@U9i
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private UserDAO userDAO; $~c?qU
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/** Gb+cT
* @param userDAO The userDAO to set. %J4]T35^2
*/ f2Frb
publicvoid setUserDAO(UserDAO userDAO){ bf2R15|t5`
this.userDAO = userDAO; -dbD&8
} [tDUR
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/* (non-Javadoc)
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* @see com.adt.service.UserManager#listUser )
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(org.flyware.util.page.Page) 1L1_x'tT%
*/ FrD.{(/~
public Result listUser(Page page)throws f'aQ T
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HibernateException, ObjectNotFoundException { G|FF
int totalRecords = userDAO.getUserCount(); e"(l
if(totalRecords == 0) CBdSgHA3>
throw new ObjectNotFoundException Vt{C80n&N
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("userNotExist"); 5 (bG
page = PageUtil.createPage(page, totalRecords); _l]`Og@Y
List users = userDAO.getUserByPage(page); <K!5N&vh
returnnew Result(page, users); F4X/ )$Dk
} 'TpW-r:
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} l=*^FK]L`
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 f"Yj'`6
jfF,:(P%W
询,接下来编写UserDAO的代码: +:1ay^YI
3. UserDAO 和 UserDAOImpl: ~a m]G0
java代码: 2pFOC;tl
;SkC[;`J
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/*Created on 2005-7-15*/ Kv"e\
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package com.adt.dao; ,
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import java.util.List; L^rtypkJ
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import org.flyware.util.page.Page; %~P]x7%|
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import net.sf.hibernate.HibernateException; 2#&9qGR
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rd Em
/** jzV*V<
* @author Joa !3Fj`Oh
*/ "{;]T
publicinterface UserDAO extends BaseDAO { AWCzu5ve
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publicList getUserByName(String name)throws VHVU*6_w
<K:?<F
HibernateException; b6_*ljM
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publicint getUserCount()throws HibernateException; DrbjqQL+.
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publicList getUserByPage(Page page)throws -yfyd$5j
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HibernateException; k6rX/ocu
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} iQ*JU2;7t
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java代码: Y{Kpopst
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