Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _Jz8{` "
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 h<<>3 A
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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 -F&U
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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 a`9L,8Ve
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分页支持类: =rA~7+}
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java代码: a/Q$cOs
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package com.javaeye.common.util; <Tw>|cFT
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import java.util.List; p=GWq(S6
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publicclass PaginationSupport {
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publicfinalstaticint PAGESIZE = 30; {U]H;~3 ?
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privateint pageSize = PAGESIZE; w1x"
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privateList items; k-V,~c
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privateint totalCount; <P ,~eX(r
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privateint[] indexes = newint[0]; d4:`@*
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privateint startIndex = 0; G2 ]H6G$M
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public PaginationSupport(List items, int +:=(#Y
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totalCount){ onCKI,"
setPageSize(PAGESIZE); [AH6~-\ x
setTotalCount(totalCount); Sgim3):Z
setItems(items); C`=p+2I]
setStartIndex(0); r;9 r!$d
} 7*Qk`*Ii
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public PaginationSupport(List items, int Ng><n}
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totalCount, int startIndex){ dG QG!l+>
setPageSize(PAGESIZE); eg<bi@C1|
setTotalCount(totalCount); ,jA)wJ
setItems(items); 3<=,1 cU
setStartIndex(startIndex); spU)]4P&
} 0tISXu-
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public PaginationSupport(List items, int `
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totalCount, int pageSize, int startIndex){ 2Y}?P+:%>
setPageSize(pageSize); h'J|K^na
setTotalCount(totalCount); !f>d_RG
setItems(items); rrg96WD
setStartIndex(startIndex); $p!yhn7
} }7fZ[J3
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publicList getItems(){ 7*j
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return items; eD$M<Eu
} "gd=J_Yw
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publicvoid setItems(List items){ HS'Vi9
this.items = items; Er/bO
} Ze<K=Q%(i
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publicint getPageSize(){ tqAd$:L
return pageSize; @3fn)YQ'
} W{z.?$SH
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publicvoid setPageSize(int pageSize){ &<zd.~N"
this.pageSize = pageSize; qQ\Y/}F
} `&0Wv0D0
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publicint getTotalCount(){ T|&[7%F3"
return totalCount; PFUO8>!pA\
} }:: S0l
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publicvoid setTotalCount(int totalCount){ 5<I
if(totalCount > 0){ [{4MR%--
this.totalCount = totalCount; -(#I3h;I
int count = totalCount / EM>}0V
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pageSize; y(R?
,wa=]
if(totalCount % pageSize > 0) YV=QF
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count++; t+oJV+@
indexes = newint[count]; &`b
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for(int i = 0; i < count; i++){ d0'JC*
indexes = pageSize * '|;X0fD
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i; 6y%0`!
} Y@'8[]=0
}else{ Gm*X'[\DD
this.totalCount = 0; 1[_mEtM:]B
} w\)|
} Qf@I)4'
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publicint[] getIndexes(){ $R<Me
return indexes; nRd)++
} .q+0pj
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publicvoid setIndexes(int[] indexes){ v}WR+)uFQ
this.indexes = indexes; :Hxv6
} .^J2.>.
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publicint getStartIndex(){ =PGs{?+&O
return startIndex; c1X1+b,
} 0"~i^
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publicvoid setStartIndex(int startIndex){ ?` SUQm
if(totalCount <= 0) O25lLNmO
this.startIndex = 0; 8* Jw0mSw
elseif(startIndex >= totalCount) 8H[:>;SI
this.startIndex = indexes HF|oBX$_
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;
[indexes.length - 1]; Y8flrM2CwG
elseif(startIndex < 0) J>d.dq>r
this.startIndex = 0; O-)-YVU
else{ 8p[)MiC5W^
this.startIndex = indexes Vh>Z,()>>@
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[startIndex / pageSize]; 5nbEf9&
} {Ay"bjZh
} P2Vg 4
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publicint getNextIndex(){ 0'nikLaKy
int nextIndex = getStartIndex() + E7-@&=]v
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pageSize; A!^q
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if(nextIndex >= totalCount) &^4++
return getStartIndex(); z3?o|A }/W
else @k&qb!Qah
return nextIndex; vq34/c^
} =B.F;40
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publicint getPreviousIndex(){ I%urz!CNE*
int previousIndex = getStartIndex() - U*.0XNKp{
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pageSize; J90v!p-
if(previousIndex < 0) 7gRgOzWfV
return0; #Fyuf,hw4
else LdJYE;k Ju
return previousIndex; YuB+k^
} S*yjee<@
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} qWw\_S
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抽象业务类 vm>b m
java代码: (h:Rh
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/** #c2ymQm
* Created on 2005-7-12 R:B^
*/ qx%}knB
package com.javaeye.common.business; Hc`A3SMR
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import java.io.Serializable; v0L\0&+
import java.util.List; s&j-\bOic9
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import org.hibernate.Criteria; DK}"b}Fvq
import org.hibernate.HibernateException; k1Q?'<`
import org.hibernate.Session; /hO1QT}xd
import org.hibernate.criterion.DetachedCriteria; orb_"Qw
import org.hibernate.criterion.Projections; O$cHZs$
import 23gPbtq/
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org.springframework.orm.hibernate3.HibernateCallback; r(9~$_(vK
import u]OW8rc
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org.springframework.orm.hibernate3.support.HibernateDaoS =FD;~
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upport; +@r*}
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import com.javaeye.common.util.PaginationSupport; _o8?E&d
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public abstract class AbstractManager extends JfPD}w
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HibernateDaoSupport { ~y7jCcd`
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privateboolean cacheQueries = false; iTaWu p
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privateString queryCacheRegion; 3h<,
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publicvoid setCacheQueries(boolean [+P#tIL
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cacheQueries){ C`q@X(_
this.cacheQueries = cacheQueries; ?Q&yEGm(
} Q$fmD
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publicvoid setQueryCacheRegion(String =z8f]/k*>
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queryCacheRegion){ b5^OQH{v
this.queryCacheRegion = 4ni3kmvX
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queryCacheRegion; 0x!2ihf
} 1UQHq@aM
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publicvoid save(finalObject entity){ &ot/nQQ
getHibernateTemplate().save(entity); 3)RsLI9
} $cZUM}@
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publicvoid persist(finalObject entity){ zen*PeIrA^
getHibernateTemplate().save(entity); +U@<\kIF
} #BSTlz
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publicvoid update(finalObject entity){ 7hcNf,
getHibernateTemplate().update(entity); /Ju;MeE9
} t2"FXTAq
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publicvoid delete(finalObject entity){ wiBVuj#
getHibernateTemplate().delete(entity); Ot`VR&}
} qcT'nZ:
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publicObject load(finalClass entity, 3*@5S]]
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finalSerializable id){ .c$316
return getHibernateTemplate().load .(WQYOMl0
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(entity, id); m?&1yU9
} =yy5D$\
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publicObject get(finalClass entity, &@3H%DP}Ql
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finalSerializable id){ x]33LQ1]
return getHibernateTemplate().get Cn[0(s6
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(entity, id); hh[jN7K
} x@Hc@R<!
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publicList findAll(finalClass entity){ +k>.Q0n%m
return getHibernateTemplate().find("from b4pm_Um
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" + entity.getName()); *2X0^H|dS
} b?'yAXk
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publicList findByNamedQuery(finalString 4f;HQ-Iv
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namedQuery){ ny54XjtG,
return getHibernateTemplate Ct%x&m:
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().findByNamedQuery(namedQuery); *H|M;G
} `F>O; >i''
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publicList findByNamedQuery(finalString query, Xp}Yw"7
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finalObject parameter){ ~appY Av
return getHibernateTemplate P$-X)c$&
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().findByNamedQuery(query, parameter); "T- `$'9
} piZJJYv t
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publicList findByNamedQuery(finalString query, c[ ]4n
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finalObject[] parameters){ ^) s2$A:L
return getHibernateTemplate L{`JRu
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().findByNamedQuery(query, parameters); Y"wUt &
} AoI/n4T^
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publicList find(finalString query){ # m *J&
return getHibernateTemplate().find Kc^;vT>3
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(query); +PuPO9jKO@
} #&7}-"Nd
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publicList find(finalString query, finalObject .>IhN 5
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parameter){ wg]j+r@
return getHibernateTemplate().find yYH 0v7vx+
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(query, parameter); 2]ape !(
} >cCR2j,r
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ |a!fhl+
return findPageByCriteria v*[.a#1^
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); M )2`+/4
} x HhN
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public PaginationSupport findPageByCriteria i?F
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(final DetachedCriteria detachedCriteria, finalint $"H{4x`-
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startIndex){ AlIpsJ[UU
return findPageByCriteria %&Q$dzgb_
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(detachedCriteria, PaginationSupport.PAGESIZE, _&b4aW9<
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startIndex); ]h5Yg/sms
} YS%h^>I^
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public PaginationSupport findPageByCriteria wD]/{
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(final DetachedCriteria detachedCriteria, finalint >M/V oV
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pageSize, E L9]QI
finalint startIndex){ g #6E|n
return(PaginationSupport) fk x \=
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getHibernateTemplate().execute(new HibernateCallback(){ *N<&GH(j
publicObject doInHibernate O|M{-)
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(Session session)throws HibernateException { p ObX42
Criteria criteria = (X3Tav
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detachedCriteria.getExecutableCriteria(session); aiu5}%U
int totalCount = uD@#
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((Integer) criteria.setProjection(Projections.rowCount n@,G8=J?
e8#h3lxJ`
()).uniqueResult()).intValue(); Yd~X77cv
criteria.setProjection L|}lccpI
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(null); Y*vW!yu
List items = f__cn^1
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criteria.setFirstResult(startIndex).setMaxResults S-|)QGxV6
aD$v2)RR
(pageSize).list(); k+ty>bP=
PaginationSupport ps = D,k"PaLP
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new PaginationSupport(items, totalCount, pageSize, RpD=]y!5_
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startIndex); >)M`IU[d^.
return ps; CyXRi}W.
} |* ;B
}, true); |='z{WS
} z-.+x3&o @
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public List findAllByCriteria(final 9vvx*rD
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DetachedCriteria detachedCriteria){ @3C>BLI8+
return(List) getHibernateTemplate =t H:,SH
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().execute(new HibernateCallback(){ jGpN,/VQa
publicObject doInHibernate Tw;3_Lj
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(Session session)throws HibernateException { 9E>|=d|(d
Criteria criteria = xY^%&n
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detachedCriteria.getExecutableCriteria(session); f m)pulz
return criteria.list(); 'g
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} A"G
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}, true); Yd=>K HVD
} sEGO2xeI
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public int getCountByCriteria(final ^!<BQP7
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DetachedCriteria detachedCriteria){ ^5h]Y;tx
Integer count = (Integer) r[b(I@T+
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getHibernateTemplate().execute(new HibernateCallback(){ U$WxHYo
publicObject doInHibernate zU
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(Session session)throws HibernateException { O\"3J(y,
Criteria criteria = <YhB8W9 P
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detachedCriteria.getExecutableCriteria(session); 1Y7Eajt-5
return z4jR[x,
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criteria.setProjection(Projections.rowCount }:KEj_~.
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()).uniqueResult(); =IQ5<;U3
} lE&&_INHQ
}, true); /2=#t-p+
return count.intValue(); GycSwQ
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} 3@M|m<_R$
} { +
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用户在web层构造查询条件detachedCriteria,和可选的 '":lB]hS
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1+jAz`nA:T
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PaginationSupport的实例ps。 w1OI4C)~
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ps.getItems()得到已分页好的结果集 117EZg]O
ps.getIndexes()得到分页索引的数组 &3J_^210
ps.getTotalCount()得到总结果数 uao0_swW5
ps.getStartIndex()当前分页索引 S~;4*7+?:
ps.getNextIndex()下一页索引 b`~p.c%(
ps.getPreviousIndex()上一页索引 w&o&jAb-M
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \KQ71yqY
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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 /
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一下代码重构了。 a1+#3X.
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我把原本我的做法也提供出来供大家讨论吧: 2[RoxKm
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首先,为了实现分页查询,我封装了一个Page类: T_@K&<
java代码: @` 1Ds
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/*Created on 2005-4-14*/ T`\x,`
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package org.flyware.util.page; t>urc
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/** qln3 k`
* @author Joa p?);eJtV/
* %_RQx2
*/ D#il*
publicclass Page { /H(?
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/** imply if the page has previous page */ si`A:14R
privateboolean hasPrePage; 52 fA/sx
Crho=RJPR
/** imply if the page has next page */ %|g>%D3Z?
privateboolean hasNextPage; TDFkxB>
#LL?IRH9^
/** the number of every page */ _aad=BrMK
privateint everyPage; k.vBj~xU
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/** the total page number */ /%}*Xh
privateint totalPage; u09:Z{tL;@
-0$55pa/@:
/** the number of current page */ >VP=MbN
privateint currentPage; ^;Y|3)vvB
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/** the begin index of the records by the current s.N7qO^:E
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query */ m#PY,y
privateint beginIndex; Y^8C)p9r
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/** The default constructor */ )vjh~ybZ
public Page(){ hyCh9YOu)
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} ]>LhkA@V
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/** construct the page by everyPage )Dw,q~xgg0
* @param everyPage 8\^}~s$$A
* */ V5sg#|&
public Page(int everyPage){ n>+mL"hs
this.everyPage = everyPage; Kwefs;<E?
} \r /ya<5
b J=Jg~&
/** The whole constructor */ TUV&vz{
public Page(boolean hasPrePage, boolean hasNextPage, DnCP
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int everyPage, int totalPage, NdtB1b
int currentPage, int beginIndex){ Bg5Wba%NK
this.hasPrePage = hasPrePage; xO^:_8=&:
this.hasNextPage = hasNextPage; =vQcYa
this.everyPage = everyPage; HJXT9;w
this.totalPage = totalPage; !UG
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this.currentPage = currentPage; 4
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this.beginIndex = beginIndex; A+SE91m
}
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/** h U`wVy
* @return Gn|F`F
* Returns the beginIndex. 1crnmJ!C
*/ s} UjGFP
publicint getBeginIndex(){ UDL!43K
return beginIndex; +Z7th7W/,
} pk?w\A}
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/** >XY`*J^
* @param beginIndex 5R'TcWf#W
* The beginIndex to set. (qqOjz
*/ vwjPmOjhS
publicvoid setBeginIndex(int beginIndex){ rai3<_W<
this.beginIndex = beginIndex; ROg(U8
N
} 0fb`08,^
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/** pP*zq"o
* @return C\/xl#e<@
* Returns the currentPage. co~Pyj
*/ :=/85\P0SU
publicint getCurrentPage(){ i@P)a'W_
return currentPage; [`{Z}q&
} ';TT4$(m
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/** tZ}
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* @param currentPage
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* The currentPage to set. &u /Nf&A
*/ 1Ty<\bZ=
publicvoid setCurrentPage(int currentPage){ 56+s~hG
this.currentPage = currentPage; O4r0R1VQM
} NLUT#!Gr
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/** ]w;rfn9D
* @return -~v|Rt
* Returns the everyPage. uJFdbBDSh
*/ fBRo_CU8!
publicint getEveryPage(){ yRSTk2N@
return everyPage; biSz?DJ>
} MaRi+3F
zo +nq%=
/** ~%^
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* @param everyPage H<v'^*(
* The everyPage to set. rqdE6y+^
*/ kSR\RuY*
publicvoid setEveryPage(int everyPage){ 8Eakif0CO
this.everyPage = everyPage; ;pqg/>W'
} 12;8o<~
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/** lzYEx
* @return o_@4Sl8
* Returns the hasNextPage. n#q<`}u,
*/ *pAV2V(!23
publicboolean getHasNextPage(){ u+'tfFds&
return hasNextPage; IPgt|if^
} "}pNe"ok
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/** NdL,F;^
* @param hasNextPage 62 O.?Ij
* The hasNextPage to set. 7B!xT2{T
*/ i\KQ!f>A
publicvoid setHasNextPage(boolean hasNextPage){ 7NDr1Z#B6V
this.hasNextPage = hasNextPage; 3gv|9T
} ]z l[H7
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/** n` xR5!de
* @return &d"G/6
* Returns the hasPrePage. .WPV dwV4U
*/ =R #Qx,
publicboolean getHasPrePage(){ M[6:p2u
return hasPrePage; {$R' WXVs
} Qp/QaVQ+
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/** H*[M\gN$
* @param hasPrePage X:6c}p%,!
* The hasPrePage to set. ``ou/Z
*/ JBJhG<J
publicvoid setHasPrePage(boolean hasPrePage){ W_kHj}dj,p
this.hasPrePage = hasPrePage; kPVO?uO
} LL2=& VK
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/** kKAP"'v
* @return Returns the totalPage. .Nw=[
* W7U2MqQ
*/ #=6E\&NC
publicint getTotalPage(){ W}5xmz
return totalPage; T(t+
iv
} A<1hOSCz\
n}'=yItVL1
/** vU767/
* @param totalPage 95YL]3V
* The totalPage to set. %]>KvoA
*/ pgOQIzu
publicvoid setTotalPage(int totalPage){ KO]T<R
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this.totalPage = totalPage; eu(:`uu
} +tVaBhd!
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} ;~"FLQg@
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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 f ` R/
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个PageUtil,负责对Page对象进行构造: B5X(ykaX~
java代码: f6p-s
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/*Created on 2005-4-14*/ @>p<3_Y1
package org.flyware.util.page; j!]YNH@
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import org.apache.commons.logging.Log; vJ'2@f$
import org.apache.commons.logging.LogFactory; s;3= {e.
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/** ^~3SSLS4"
* @author Joa r]b_@hT',
* ~S8* t~
*/ !t gi
publicclass PageUtil { >U%gctIg
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privatestaticfinal Log logger = LogFactory.getLog bI:zp!-.
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(PageUtil.class); y *fDwd~
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/** H^s<{E0<
* Use the origin page to create a new page n
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* @param page paKSr|O
* @param totalRecords k}
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* @return #MRMNL@
*/ %`&2+\`
publicstatic Page createPage(Page page, int ,M^ P!
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totalRecords){ m+lvl
return createPage(page.getEveryPage(), UE$UR#T'w
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page.getCurrentPage(), totalRecords); )?X-(4
} v
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/** R,pX:H+
* the basic page utils not including exception TrLu~4
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handler ~ xft
* @param everyPage >D(R YI
* @param currentPage rvnT6Ve
* @param totalRecords xHz[t6;4;
* @return page gqu?o&>9
*/ z@B=:tf
publicstatic Page createPage(int everyPage, int Fsif6k=4
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currentPage, int totalRecords){ !V
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everyPage = getEveryPage(everyPage); SjwyLc
currentPage = getCurrentPage(currentPage); cp#JBHO
int beginIndex = getBeginIndex(everyPage, A?-oL='
yIDD@j=l
currentPage); J6L K
int totalPage = getTotalPage(everyPage, DX"xy
p2DrEId
totalRecords); .ys6"V|31
boolean hasNextPage = hasNextPage(currentPage, ~TSy<t~%-
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totalPage); >hk=VyU;
boolean hasPrePage = hasPrePage(currentPage); )u/yF*:n
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returnnew Page(hasPrePage, hasNextPage, >(?9?
everyPage, totalPage, "CUty"R8
currentPage, 1n:8s'\
?<(m
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beginIndex); [^U#Qj)hL
} lzYnw)Pv
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privatestaticint getEveryPage(int everyPage){ ?34 e-
return everyPage == 0 ? 10 : everyPage; iVy7elT;R
} V`bi&1?6\
5A
sP5
privatestaticint getCurrentPage(int currentPage){ ,!7 H]4Qx
return currentPage == 0 ? 1 : currentPage; 1e&QSzL
} h $L/<3oP6
;uwRyd
privatestaticint getBeginIndex(int everyPage, int ]cGA~d
A7%:05
currentPage){ t4-pM1]1_
return(currentPage - 1) * everyPage; f"u%J/e &
} k;w- E
.)<(Oj|4
privatestaticint getTotalPage(int everyPage, int rz@=pR :
-lhLA`6_R
totalRecords){ nIU 6h
int totalPage = 0; 1rkE yh??
B:!W$<
if(totalRecords % everyPage == 0) Z(Bp 0a
totalPage = totalRecords / everyPage; ~[\_N\rm
else jC7&s$>Q"g
totalPage = totalRecords / everyPage + 1 ; u"d~!j1
AO=h
23ZI
return totalPage; *T~Ve;3h;
} ub;ZtsM,%
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privatestaticboolean hasPrePage(int currentPage){ /XhIx\40l
return currentPage == 1 ? false : true; =u+d_'P7-R
} 2UFv9
F@<CsgKB-
privatestaticboolean hasNextPage(int currentPage, (Nx;0"5IX
h\PHKC2
int totalPage){ J,AR5@)1
return currentPage == totalPage || totalPage == op6CA "w
1. rj'
0 ? false : true; L(khAmm
} l PK
+$f$
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} wyQzM6:,yX
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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。 sfOHarww
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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 8'f4 Od ?
IiZ&Pr
做法如下: -mRA#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,;(PwJe
pGK;1gVj
的信息,和一个结果集List: N9vP7
java代码: .] sf0S!
rwG CUo6Z
vh*U]3@
/*Created on 2005-6-13*/ 4qYUoCR&
package com.adt.bo; U
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import java.util.List; Fm #w2o
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import org.flyware.util.page.Page; ^1L>l9F
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/** |"9 #bU
* @author Joa i}o[- S4
*/ ]@0NO;bK>F
publicclass Result { 9$|Gfyv
]- 4QNc=
private Page page;
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private List content; .?!N^_ Ez3
NN1$'"@NL
/** 6+KHQFb&N
* The default constructor R#DwF,
*/ 5GPo*Qpl
public Result(){ >$,y5 AJ&
super(); hDp6YV,q
} N~NQ6:R[
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/** Jte#ZnP
* The constructor using fields r?*NhLG;
* [g Z"a*
* @param page ty*@7g0k
* @param content }-o{ASC#
*/ SJ};TEA
public Result(Page page, List content){ vJU*>U,
this.page = page; K
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this.content = content; #~.w&~:
} !Wy[).ZAf
O=dJi9;`#_
/** }LijnHH.
* @return Returns the content. LI6hEcM=
*/ Wf&W^Q
publicList getContent(){ BZXUwqEh
return content; `QUy;%+
} 4)<~4 '
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/** }Iz7l{al
* @return Returns the page. _+^ 2^TW
*/ `/MvQ/
public Page getPage(){ =l0Jb#d
return page; }QsZ:J.
} 2d {y M(=(
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/** fz3lV
* @param content ~35U]s@v
* The content to set. /2HN>{F^Y
*/ Cc, `}SP
public void setContent(List content){ E gDQ+(
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this.content = content; H=\!2XS
} )5.C]4jol
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/** &%_& 8DkG
* @param page @j4U^"_QB
* The page to set. Eb=#9f%y>&
*/ vQa'S-@u
publicvoid setPage(Page page){ <6G11-K
this.page = page; ?"KC-u|
} w1|A5q'M
} f*24)Wn<
l?q%?v8
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6Vbzd0dk
2. 编写业务逻辑接口,并实现它(UserManager, W7\&~IWub
Cb_oS4vM
UserManagerImpl) \ AC|?/sH
java代码: KPpHwcYxT
G5,~Z&}YS
$L2%u8}8:
/*Created on 2005-7-15*/ nxJee=qH
package com.adt.service; o8Z[+;
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import net.sf.hibernate.HibernateException; wHem5E
;kJu$U
import org.flyware.util.page.Page; 2Gs$?}"a
hG_?8:W8HT
import com.adt.bo.Result; gn{=%`[
@Kgl%[NmX
/** n
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* @author Joa _6Eu2|vM&
*/ 7'-j%!#w
publicinterface UserManager { eJo3 MK
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public Result listUser(Page page)throws rO:u6."_
cf7v[ZZ}
HibernateException; z 8*8OWM
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} }rdIUlVO\
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}I!hOD>]O
P N*JR
olW|$?
java代码: q,2]5'
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sncIqsZ
/*Created on 2005-7-15*/ 4TwQO$C
package com.adt.service.impl; cFagz* !
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import java.util.List; )!Bd6-
iHp\o=#
import net.sf.hibernate.HibernateException; 4"vaMa
2F8|I7R
import org.flyware.util.page.Page; ((rv]f{
import org.flyware.util.page.PageUtil; A`u$A9[
'?Jxt:<
import com.adt.bo.Result; e\b`n}nC
import com.adt.dao.UserDAO; PjIeZ&p
import com.adt.exception.ObjectNotFoundException; =q"eU=9
import com.adt.service.UserManager; `PL[lP-<
?QA\G6i4
/** !tHt,eJy
* @author Joa poJg"R4
*/
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publicclass UserManagerImpl implements UserManager { ]p~IYNl2%j
CWO=0_>2
private UserDAO userDAO; S
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\NqEw@91B
/** ^<0IB#dA
* @param userDAO The userDAO to set. b%t+,0s|
*/ .!}hhiF,Z
publicvoid setUserDAO(UserDAO userDAO){ /i)Hb`(S
this.userDAO = userDAO; IOK}+C0e
} p$k\m|t
SLhEc
/* (non-Javadoc) Y1dVM]l
* @see com.adt.service.UserManager#listUser "*7C`y5&P
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(org.flyware.util.page.Page) 0
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*/ r
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public Result listUser(Page page)throws o/,NG U
> 4oY 3wk8
HibernateException, ObjectNotFoundException { 1zktU.SZ
int totalRecords = userDAO.getUserCount(); A{<xc[w;p
if(totalRecords == 0) _B,_4}
throw new ObjectNotFoundException [^~7]2 i
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("userNotExist"); .~}z4r
page = PageUtil.createPage(page, totalRecords); #ycL'T`X%
List users = userDAO.getUserByPage(page); RH~3M0'0
returnnew Result(page, users); r?l;I3~
} <1&Ke
<3hA!$o~
} K<v:-TjQZ:
,PWj_}|L[
*wi}>_\
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 N*DhjEU)[
&2EBk= X
询,接下来编写UserDAO的代码: nEy]`
3. UserDAO 和 UserDAOImpl: tk/`%Q
java代码: *(cU]NUH_
fn9#>~vrD
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/*Created on 2005-7-15*/ "D*Wi7
package com.adt.dao; &B!%fd.'
w5]l1}rl
import java.util.List; J<JBdk
)'q%2%Ak
import org.flyware.util.page.Page; KIL18$3J
)qPSD2h
import net.sf.hibernate.HibernateException; GLKO]y
2r];V'r
/** zL s^,x
* @author Joa j.3o W
*/ ,2 WH/"
publicinterface UserDAO extends BaseDAO { m%QqmTH
|ia@,*KD
publicList getUserByName(String name)throws ykq'g|
.V%*{eHLL
HibernateException; >kdM:MK
OR+A_:c.D
publicint getUserCount()throws HibernateException; C]`eH*z~8
/hdf{4
publicList getUserByPage(Page page)throws 4FA|[An
[V@yRWI
HibernateException;
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} {U
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"+iAd.qd
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java代码: ^i<}]c_|f
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L(WOet( '
/*Created on 2005-7-15*/ _g6m=N4
package com.adt.dao.impl; Sb^
b)q"
A|<;
import java.util.List; |#TXE|#ux
$cK^23H/Fj
import org.flyware.util.page.Page; 7;HUE!5,^l
;.Zh,cU
import net.sf.hibernate.HibernateException; N4 [E~-
import net.sf.hibernate.Query; :$"7-a%f
R'EW7}&
import com.adt.dao.UserDAO; U($^E}I2(
L? ;/cO^
/** ,0T)Oc|HL/
* @author Joa -
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*/ <q7s`,rG
public class UserDAOImpl extends BaseDAOHibernateImpl \7E`QY4
oofFrAaT
implements UserDAO { 5fHYc0
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/* (non-Javadoc) Ea`OT+#h(*
* @see com.adt.dao.UserDAO#getUserByName i
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",Wf uz
(java.lang.String) Pi%tsKk%
*/ \o9@[t>&2
publicList getUserByName(String name)throws 6H;kJHn
$T*KaX\{B
HibernateException { u[t>Tg2R
String querySentence = "FROM user in class y<r44a_!
onzA7Gre
com.adt.po.User WHERE user.name=:name"; q[boWW
Query query = getSession().createQuery ZA.fa0n
aBCOGtf
(querySentence); yQS04Bl]
query.setParameter("name", name); =mJF_Ri
return query.list(); DS
1JF
} EW5]!%
x_ySf!ih
/* (non-Javadoc) k
E_ky)
* @see com.adt.dao.UserDAO#getUserCount() ry,}F@P&
*/ 70<K.T<b
publicint getUserCount()throws HibernateException { /s-d?
int count = 0; luF#OP C
String querySentence = "SELECT count(*) FROM OQ|,-
a-Fqp4
user in class com.adt.po.User"; --/-D5
Query query = getSession().createQuery &V;x 4
sUda
(querySentence); xL&PJ /'
count = ((Integer)query.iterate().next 6ZHv,e`?
|Y4q+sDW
()).intValue(); dKe@JQ+-z
return count; x=3I)}J(kn
} u.&|CF-
NlFo$Y
/* (non-Javadoc) a&:>Ped"
* @see com.adt.dao.UserDAO#getUserByPage rHo6iJj
)GCLK<,swu
(org.flyware.util.page.Page) ZX]A )5G
*/ oF&IC
j0
publicList getUserByPage(Page page)throws Z`"n:'&
*C/KM;&
HibernateException { /T#o<D
String querySentence = "FROM user in class gDc]^K4>
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com.adt.po.User"; (lWKy9eTy`
Query query = getSession().createQuery 1 ?]J;9p
DD6 'M
U4
(querySentence); A xR\ned
query.setFirstResult(page.getBeginIndex()) &u4Ve8#
.setMaxResults(page.getEveryPage()); i\Q":4
return query.list(); PE7t_iSV
} >!G5]?taa
E$&;]a
} 2E([#Pzb
HqDa2q4
(T2<!&0 @
dff#{
M->Kz{h?j
至此,一个完整的分页程序完成。前台的只需要调用 o7QK8#
tQ6| PV
userManager.listUser(page)即可得到一个Page对象和结果集对象 -sD:+Te
!z.^(Tj
的综合体,而传入的参数page对象则可以由前台传入,如果用 xF^r`
wISzT^RS
webwork,甚至可以直接在配置文件中指定。 YL!oF^XO
*q[^Q'jnN
下面给出一个webwork调用示例: Y/!0Q6<[2Y
java代码: iQ0&