Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 y6Xfddd61
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^.jIus5
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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 X
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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 y]eH@:MJ;A
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分页支持类: +g ovnx
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java代码: I"*g-ji0
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package com.javaeye.common.util; x:=Kr@VP
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import java.util.List; yJ8WYQQMG
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publicclass PaginationSupport { ^dH#n~Wx0
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publicfinalstaticint PAGESIZE = 30; x- ) D@dw<
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privateint pageSize = PAGESIZE; a^i`DrX
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privateList items; -wlob`3
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privateint totalCount; |{cdXbr
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privateint[] indexes = newint[0]; |//cA2@.
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privateint startIndex = 0; T=:&W3
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public PaginationSupport(List items, int NS6Bi3~
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totalCount){ CF>k_\/Bj
setPageSize(PAGESIZE); <=n$oMO
setTotalCount(totalCount); ymXR#E
setItems(items); 9I=J#Hi|+
setStartIndex(0); >[,Rt"[V
} hFuS>Hx
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public PaginationSupport(List items, int :^lyVQ%@
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totalCount, int startIndex){ G+AD
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setPageSize(PAGESIZE); j2deb`GD
setTotalCount(totalCount); 6'395x_.\
setItems(items); ,7SLc+
setStartIndex(startIndex); d|]F^DDuI
} T^S|u8f
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public PaginationSupport(List items, int F%bv
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totalCount, int pageSize, int startIndex){ |f'U_nE#R/
setPageSize(pageSize); enlk)_btp
setTotalCount(totalCount); d
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setItems(items); fGb(=l
setStartIndex(startIndex); IV_uf
} z,}1K!
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publicList getItems(){ )y'`C@ijI
return items; r
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} b|n%l5
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publicvoid setItems(List items){ z|F>+6l"Y7
this.items = items; 4z Af|Je
} EonZvT-D=
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publicint getPageSize(){ NWNH)O@
return pageSize; REB8_ H"
} D4G*K*z,w4
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publicvoid setPageSize(int pageSize){ KM< +9`
this.pageSize = pageSize; >FFZ8=
} ?cCh?>h
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publicint getTotalCount(){ R}Uvi9?
return totalCount; :aLShxKA
} cQzd0X
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publicvoid setTotalCount(int totalCount){ >},O_qx
if(totalCount > 0){ 5|x&Z/hL
this.totalCount = totalCount; 7!hL(k[
int count = totalCount / Q{b Z D*
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pageSize; r-'\<d(J$
if(totalCount % pageSize > 0) yfiRMN"2
count++; ;5ugnVXu
indexes = newint[count]; RPPxiYU^
for(int i = 0; i < count; i++){ 2,/("lV@0
indexes = pageSize * IE: x&q`3
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i; wJ1qJ!s@
} lg&"=VXx51
}else{ oiJa1X
this.totalCount = 0; !;pmql
} V%dMaX>^i
} 4otB1{
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publicint[] getIndexes(){ r.xGvo{iY
return indexes; d"Y9go"Z
} c~ l$_A
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publicvoid setIndexes(int[] indexes){ x`{ni6}
this.indexes = indexes; Y<:%_]]
} hUSr1jlA
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publicint getStartIndex(){ ml.l( 6A
return startIndex; f?#:@ zcL
} s#&jE
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publicvoid setStartIndex(int startIndex){ %<O'\&!,
if(totalCount <= 0) 7.CzS
this.startIndex = 0; j7<`^OG
elseif(startIndex >= totalCount) ]x:>~0/L
this.startIndex = indexes VhT4c+Zs
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[indexes.length - 1]; 8^\DQ&D
elseif(startIndex < 0) 5b0Ipg
this.startIndex = 0; Ko\m8\3?fK
else{ /8q7pwV
this.startIndex = indexes Zla5$GM
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[startIndex / pageSize]; lEQ63)Z
} zu(/c
} S"CsY2;
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publicint getNextIndex(){ 0fxA*]h
int nextIndex = getStartIndex() +
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pageSize; yrR<F5xge
if(nextIndex >= totalCount) RQy|W}d_
return getStartIndex(); Ik>sd@X*|
else %((F}9_6
return nextIndex; ppR~e*rv-
} =\J^_g4-l
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publicint getPreviousIndex(){ qeQTW@6
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int previousIndex = getStartIndex() - <'v?WV_
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pageSize; F:n(yXA
if(previousIndex < 0) ']u w,b
return0; *ls}r5k2Y
else SgAY/#
return previousIndex; Os*,@N3t
} yi"V'Us
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} *oY59Yf
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抽象业务类 F&lWO!4
java代码: M cNj TD
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/**
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* Created on 2005-7-12 D4}WJMQ7s
*/
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package com.javaeye.common.business; p !AQ
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import java.io.Serializable; B*zb0hdo:
import java.util.List; {}D8Y_=9\
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import org.hibernate.Criteria; nrUrMnlg
import org.hibernate.HibernateException; 9^4^EY#
import org.hibernate.Session; 2Q|Vg*x\U
import org.hibernate.criterion.DetachedCriteria; 3VCyq7B^
import org.hibernate.criterion.Projections; g4=}].
import 0jrcXN~
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org.springframework.orm.hibernate3.HibernateCallback; m qPWCFP
import o83HR[
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org.springframework.orm.hibernate3.support.HibernateDaoS 5f=e
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upport; 7xVI,\qV
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import com.javaeye.common.util.PaginationSupport; ='pssdB
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public abstract class AbstractManager extends gA2Il8K
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HibernateDaoSupport { j Z3N+_J1
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privateboolean cacheQueries = false; @H@&B`K d
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privateString queryCacheRegion; )KaQ\WJ:
^ ^}
publicvoid setCacheQueries(boolean Z2PLm0%:
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cacheQueries){ .J%}ROm
this.cacheQueries = cacheQueries; Zr;.`(>
} TcpD*%wW
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publicvoid setQueryCacheRegion(String gD _tBv
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queryCacheRegion){ .o:Pe2C
this.queryCacheRegion = QP7EP aW
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queryCacheRegion; rP2^D[uM.
} 6.EfM^[
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publicvoid save(finalObject entity){ UrH^T;#
getHibernateTemplate().save(entity);
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} M7eO5
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publicvoid persist(finalObject entity){ )!|K3%9
getHibernateTemplate().save(entity); w/d9S(
} kkyn>Wxv
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publicvoid update(finalObject entity){ .m;1V6
getHibernateTemplate().update(entity); WQv~<]1JF
} @-kzSm
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publicvoid delete(finalObject entity){ 8s?;<6
getHibernateTemplate().delete(entity); \&2GLBKpe
} ;#EB0TK
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publicObject load(finalClass entity, (FH4\ 't)
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finalSerializable id){ fR5
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return getHibernateTemplate().load ?5$\8gZ
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(entity, id); J0d +q!
} ,BW^j.7
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publicObject get(finalClass entity, BG-uKJ ^
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finalSerializable id){ 9C|T/+R
return getHibernateTemplate().get 9 ?MOeOV8
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(entity, id); -*e$>w[.N
} &^63*x;hE
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publicList findAll(finalClass entity){ 2i |wQU5w
return getHibernateTemplate().find("from 9{70l539
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" + entity.getName()); WE|L{
} fS1N(RZ1
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publicList findByNamedQuery(finalString 9s73mu`Twg
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namedQuery){ z;#}uC
return getHibernateTemplate q&jZmr
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().findByNamedQuery(namedQuery); qAR~js`5
} eU@yw1N
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publicList findByNamedQuery(finalString query, -CtA\<7I
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finalObject parameter){ %lv2 ;-
return getHibernateTemplate 6}C4 SZ
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().findByNamedQuery(query, parameter); ^=OjsN
} eJ'2CM6
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publicList findByNamedQuery(finalString query, TjD`<k
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finalObject[] parameters){ FLEf(
return getHibernateTemplate :/~`"`#1
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().findByNamedQuery(query, parameters); >bz}IcZP
} IJS9%m#
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publicList find(finalString query){ X]C-y,r[M
return getHibernateTemplate().find kul&m|
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(query); )uwpeq$j7l
} {*
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publicList find(finalString query, finalObject E|6X.Ny]
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parameter){ EZ1H0fm
return getHibernateTemplate().find 5SR29Z[
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(query, parameter); #4%,09+
} k-e_lSYk&c
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public PaginationSupport findPageByCriteria b]4yFwb
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(final DetachedCriteria detachedCriteria){ ua`2
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return findPageByCriteria e{To&gy~
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); jl3RE|M\<
} ;OPz T9
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public PaginationSupport findPageByCriteria GG(rp]rgl
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(final DetachedCriteria detachedCriteria, finalint {(ey!O
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startIndex){ 6D{|! i|r4
return findPageByCriteria W zy8
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(detachedCriteria, PaginationSupport.PAGESIZE, bi#o1jR
`@?l{
startIndex); ln9MVF'!&
} (d4zNYK
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public PaginationSupport findPageByCriteria "F"G(ba^
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(final DetachedCriteria detachedCriteria, finalint [g&Q_+,j
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pageSize, [7|}h/
finalint startIndex){ =]-!
return(PaginationSupport) c!{.BgGN
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getHibernateTemplate().execute(new HibernateCallback(){ FEU$D\1y
publicObject doInHibernate ;P5\EJo
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(Session session)throws HibernateException { lQi2ym?
Criteria criteria = -("79v>#
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detachedCriteria.getExecutableCriteria(session); jY87NHg
int totalCount = s67$tlV
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((Integer) criteria.setProjection(Projections.rowCount Rp}6}4=d
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()).uniqueResult()).intValue(); Mgcq'{[~Y=
criteria.setProjection k5g\s9n]
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(null); |=jgrm1yj
List items = `j_R ?mY
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criteria.setFirstResult(startIndex).setMaxResults $'?CY)h{
<JF78MD\
(pageSize).list(); #vLDN R
PaginationSupport ps = ""CJlqU
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new PaginationSupport(items, totalCount, pageSize, m]7Y
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startIndex); qL A
return ps; F ypqf|
} MI',E?#yB
}, true); 4\Y=*X
} [RC|W%<Z>
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public List findAllByCriteria(final jqb,^T|j;m
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DetachedCriteria detachedCriteria){ nHyWb6
return(List) getHibernateTemplate oUltr
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().execute(new HibernateCallback(){ F3';oyy
publicObject doInHibernate rAP+nh ans
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(Session session)throws HibernateException {
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Criteria criteria = LP=!u~?
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detachedCriteria.getExecutableCriteria(session); 3,N7Nfe
return criteria.list(); >tib21*
} !l.Rv_o<O
}, true); sE>'~+1_O
} d@8_?G}
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public int getCountByCriteria(final pA+Qb.z5z
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DetachedCriteria detachedCriteria){ Z# 7HuAF{]
Integer count = (Integer) +1h^9Y'
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getHibernateTemplate().execute(new HibernateCallback(){ GN=F-*2
publicObject doInHibernate ~;bwfp_
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(Session session)throws HibernateException { dn%/SJC
Criteria criteria = #?}Y~Oe
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detachedCriteria.getExecutableCriteria(session); 8ne5 B4
return 6\~m{@
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criteria.setProjection(Projections.rowCount A{&Etu(K
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()).uniqueResult(); pxDZ}4mOh
} &(Xp_3PO
}, true); \Cx3^
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return count.intValue(); ->8n.!F}
} nqiy)ZN#R
} #BT=
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用户在web层构造查询条件detachedCriteria,和可选的 tkNuM0
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 qDcl;{L
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PaginationSupport的实例ps。 ]S;e#u{QE
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ps.getItems()得到已分页好的结果集 "uZ'oN
ps.getIndexes()得到分页索引的数组 8&dmH&
ps.getTotalCount()得到总结果数 0Apvuf1
ps.getStartIndex()当前分页索引 M{O2O(
ps.getNextIndex()下一页索引 5
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ps.getPreviousIndex()上一页索引 s2w.V
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 K;[V`)d'
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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 OP:;?Fs9`
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一下代码重构了。 9H.E15B
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我把原本我的做法也提供出来供大家讨论吧: 0{A VH/S
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首先,为了实现分页查询,我封装了一个Page类: BMFpkK9|
java代码: I"<~!krt%
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/*Created on 2005-4-14*/ ?P"ht
package org.flyware.util.page; /V&$SRdL*
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/** W-Hw%bwN/q
* @author Joa VZ_4B *D
* J5|Dduv
*/ H+*o @0C\~
publicclass Page { T*A_F
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/** imply if the page has previous page */ 0 w@~ynW[
privateboolean hasPrePage; -*?a*q/#nQ
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/** imply if the page has next page */ go{'mX) }u
privateboolean hasNextPage; u\=Nu4)Z
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/** the number of every page */ = @ph
privateint everyPage; m0=CD
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/** the total page number */ n:k~\-&WJ
privateint totalPage; [!bTko>rSB
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/** the number of current page */ 3~Ipcr
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privateint currentPage; %li'j|
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/** the begin index of the records by the current u!{P{C
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query */ #C!8a
privateint beginIndex; #kma)_X
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/** The default constructor */ 9"MC<
public Page(){ E;-R<X5n
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} j##IJm
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/** construct the page by everyPage N],A&}30
* @param everyPage o*r\&!NIw
* */ v?d~H`L
public Page(int everyPage){ chfj|Ce]x
this.everyPage = everyPage; $ n
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} $i~DUT(
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/** The whole constructor */ k[G? 22t
public Page(boolean hasPrePage, boolean hasNextPage, Cww$ A %}
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int everyPage, int totalPage, ,|T
int currentPage, int beginIndex){ s(wbsRVP8
this.hasPrePage = hasPrePage; t;y>q
this.hasNextPage = hasNextPage; .
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this.everyPage = everyPage; S ._9
this.totalPage = totalPage; c9f~^}jNb
this.currentPage = currentPage; $&lS7}
this.beginIndex = beginIndex; h'kgL~+$
} #^Sd r-
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/** +s_@964
* @return B6=8cf"i
* Returns the beginIndex. C=9|K`g5 R
*/ ~} wPiu,
publicint getBeginIndex(){ P9Rq'u
return beginIndex; T7!a@
} hQl3F6-ud
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/** 5O*.qp?
* @param beginIndex BnAia3z
* The beginIndex to set. Eiz\Nb
*/ LFg<j1Gk`
publicvoid setBeginIndex(int beginIndex){ Pme`UcE3H
this.beginIndex = beginIndex; _=4Dh/Dv
} yfuvU2nVH
o.Q|%&1
/** E: XzX Fxx
* @return #7gOtP#{
* Returns the currentPage. &\c$s
*/ #sNa}292"
publicint getCurrentPage(){ i"|'p/9@q
return currentPage; ^qV*W1|0
} w*Kw#m'U
cWh Aj>?_Q
/** $K;4=zN>t:
* @param currentPage m6'YFpf)V
* The currentPage to set. "L{;=-e
*/ oPre$YT}h
publicvoid setCurrentPage(int currentPage){ $@Hw DRP
this.currentPage = currentPage; T<p>:$vo
} `\O[9.B
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/** %2/WyD$U
* @return mL3'/3-7:V
* Returns the everyPage. }54\NSj0
*/ jd(=? !_
publicint getEveryPage(){ !BK^5,4?--
return everyPage; %&e5i
} /Q{Jf+>R>
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/** HykJ}ezX4
* @param everyPage B`T9dL[E4
* The everyPage to set. Q"QrbU
*/ 5#WZXhlc}
publicvoid setEveryPage(int everyPage){ .}a@OLJd
this.everyPage = everyPage; KX`MX5?x
} 5/neV&VcB
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/** NIV&)`w
* @return 4my8 p Fk
* Returns the hasNextPage. FC vR
*/ H(n_g
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publicboolean getHasNextPage(){ 7J0PO}N
return hasNextPage; s
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} S{fNeK
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/** E/5w
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* @param hasNextPage T[ mTA>d
* The hasNextPage to set. .@ 1\26<
*/ )c+ZQq
publicvoid setHasNextPage(boolean hasNextPage){ nFxogCn
this.hasNextPage = hasNextPage; t%N#Yh!
} %H%>6z x
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/** ]9b*!n<z
* @return H(
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* Returns the hasPrePage. k('2K2P
*/ VI37
publicboolean getHasPrePage(){ ~e'FPVDn
return hasPrePage; LTFA2X&E=
} Fvi<5v
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/** )UN@|IX
* @param hasPrePage /UM9g+Bb
* The hasPrePage to set. W}JJaZR*X
*/ hM+nA::w
publicvoid setHasPrePage(boolean hasPrePage){ s)_sLt8?
this.hasPrePage = hasPrePage; 9SMM%(3, r
} u3ce\
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/** tXPS@4F
* @return Returns the totalPage. W99Fb+$I
* E~{-RZNK
*/ /:C"n|P7Z
publicint getTotalPage(){ 7F.>M
return totalPage; #WfJz}P,!
} NeeymyW
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/** K;S&91V)=
* @param totalPage $6ITa }o
* The totalPage to set. K Rm4r
*/ >Li
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publicvoid setTotalPage(int totalPage){ r ZGA9duy
this.totalPage = totalPage; >(d+E\!A
} vhKeW(z
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} =d(
6
)
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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 g/JAr<
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个PageUtil,负责对Page对象进行构造: qH"0?<$9
java代码: Ntg#-_]
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/*Created on 2005-4-14*/ A5
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package org.flyware.util.page; f)N67z6
@CWfhc-Ub
import org.apache.commons.logging.Log; 'p Z~3q
import org.apache.commons.logging.LogFactory; ~hP[[?
]Jv Z:'g}
/** .L6t3/^
* @author Joa 7.akp
* )M^;6S
*/ b]CJf8'u
publicclass PageUtil { M`iJ6L
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privatestaticfinal Log logger = LogFactory.getLog zKgW9j<(
NL2n\%n
(PageUtil.class); `4l>%S8y:
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/** ]FQ4v.7
* Use the origin page to create a new page E2%7 v
* @param page H$\?D+xlf
* @param totalRecords hoSk
* @return s7T=/SC54
*/ 7Zr jU{
publicstatic Page createPage(Page page, int <%) :'0q&
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totalRecords){ s7df<dBC
return createPage(page.getEveryPage(), h'T\gF E%
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page.getCurrentPage(), totalRecords); WDgp(Av!
} nE::9Yh8z
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/** zCPjuS/~
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* the basic page utils not including exception 1NJ*EzJ~?
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handler j>0S3P,
* @param everyPage 2Uu,Vv
* @param currentPage TvM{ QGN
* @param totalRecords VwtGHF'
* @return page c.jnPVf:
*/ _FAwW<S4B
publicstatic Page createPage(int everyPage, int T /[)U
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currentPage, int totalRecords){ FKL}6W:
everyPage = getEveryPage(everyPage); M(oW;^B
currentPage = getCurrentPage(currentPage); <2|x]b8
int beginIndex = getBeginIndex(everyPage, 5Ko"-
9DPf2`*$
currentPage); ~V5k
int totalPage = getTotalPage(everyPage, ho^1T3
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totalRecords); dbnH#0i
boolean hasNextPage = hasNextPage(currentPage, 0ZPPt(7
*4A.R&Vu
totalPage); `Gsh<.w!7
boolean hasPrePage = hasPrePage(currentPage); B}r@x z
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returnnew Page(hasPrePage, hasNextPage, I0)iC[s8;
everyPage, totalPage, L~vNW6#W
currentPage, z[OW%(vrm
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beginIndex); ^{Syg;F=
} XXe7w3x{
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privatestaticint getEveryPage(int everyPage){ ?nUV3#6{
return everyPage == 0 ? 10 : everyPage; i.K}(bo;b
} ]T
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privatestaticint getCurrentPage(int currentPage){ !j7b7<wR
return currentPage == 0 ? 1 : currentPage; zhYE#hv2
} ojyG|Y
E7*1QR{Q
privatestaticint getBeginIndex(int everyPage, int ocL
Z< uwqA
currentPage){ Rs<,kMRGVL
return(currentPage - 1) * everyPage; EcwHO
} e(!a~{(kq%
mHw1n=B
privatestaticint getTotalPage(int everyPage, int ;Oe6SNquT
hM>xe8yE
totalRecords){ vuw1ycy)
int totalPage = 0; ?\^u},HnE|
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if(totalRecords % everyPage == 0) XUMCz7&j
totalPage = totalRecords / everyPage; b\^ Sz{
else )OjbmU!7
totalPage = totalRecords / everyPage + 1 ; UDp"+nS
K8e >sU.
return totalPage; |wK)(s
} cH2
nG:H
TR
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privatestaticboolean hasPrePage(int currentPage){ {9C(\i +
return currentPage == 1 ? false : true; Az0Yt31=
} C5XCy%h
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privatestaticboolean hasNextPage(int currentPage, hoU&'P8
Rzb663d
int totalPage){ (y(V,kXwa8
return currentPage == totalPage || totalPage == TXrC5AJx
](8XC_-U'
0 ? false : true; Uv%"45&7
} p8F|]6Z
4I,@aj46
}m0Lr:vq<r
} M5P63=1+
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Kz^aW
@?gH3Y_
k^ZUOWmU|
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。 b[BSUdCB
G%'h'AV"
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 ]=]'*Z%
-,XS2[
做法如下: oD"fRBS+$
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 PT\5P&2o@
UbMcXH8=F
的信息,和一个结果集List: xFyMg&
java代码: !q7M+j4
#2cH.`ty
xn6E f"
/*Created on 2005-6-13*/ kW-5H;>
package com.adt.bo; #!,xjd
ODEy2).
import java.util.List; *wh'4i}u
aD3$z;E
import org.flyware.util.page.Page; x`B:M7+\
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/** 7Y#b7H
* @author Joa :ye)%UU"|:
*/ (&
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publicclass Result { <GoE2a4Va
q*'hSt@+D
private Page page; {]Lc]4J
lg!1q8
private List content; .|iUDp6vz
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/**
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* The default constructor -u8@ .
*/ ?Bh}
public Result(){ w#JF7;
super(); lgnF\)
} ;M'R/JlUN
*[vf47)r!
/** ,t)mCgbcO
* The constructor using fields Z?v9ub~%
* ? 4.W
_
* @param page m{V@Om
* @param content "BzRLg!J
*/ Zr$PSp}
public Result(Page page, List content){ _$fxo D9
this.page = page; E6@+w. VVO
this.content = content; _IgG8)k;
} "%}PVO!
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/** e?f[t*td
* @return Returns the content. *b7v)d#
*/ "CZ`hx1|^
publicList getContent(){ `qfVgT=2
return content; jj.yB#T
} >,~JQ%1
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/** 5Impv3qaZ
* @return Returns the page. u
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*/ ! Noabt
public Page getPage(){ 8fDnDA.e
return page; Dnd
} s"sX#l[J
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/** #z5'5|3
* @param content {AcKBib
* The content to set. *qq %)7
*/ MJ7!f+!5
public void setContent(List content){ J@R+t6$3O
this.content = content; SS H/q/
} '!y ^
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/** >i=O =w
* @param page B!8]\D
* The page to set. [IHT)%>E8&
*/ F<^,j7@
publicvoid setPage(Page page){ A\: =p
this.page = page; =-vk}O0C
} .Q?AzU,2D
} +$v$P!),
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XKR?vr7A2
2. 编写业务逻辑接口,并实现它(UserManager, jh=:Q P/
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UserManagerImpl) ;Y)?6^"
java代码: 778L[wYe
UQTt;RS*zS
bJe^x;J9
/*Created on 2005-7-15*/ Fd ]! 7
package com.adt.service; g0ug:- R
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import net.sf.hibernate.HibernateException; %K/rPhU
Bp4QHv9xqL
import org.flyware.util.page.Page; KH@M &
>=^
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import com.adt.bo.Result; n#x{~oQc
3[8'pQ!&
/** Z0-W%W
* @author Joa ,a?em'=
*/ WQ6E8t)
publicinterface UserManager { bggSYhJ?\#
os#j;C]l
public Result listUser(Page page)throws r]8B6iV
4RdpROK
HibernateException; B8;ZOLAU
d B?I(
} qOk4qbl[
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~){*XJw6
java代码: O>'o; 0
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/*Created on 2005-7-15*/ /#Ew{RvW'
package com.adt.service.impl; !7}5"j
;A
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import java.util.List; u/k#b2BqL
Ar>Om!]=v
import net.sf.hibernate.HibernateException; ;E##bdSCA
we{*%8I;
import org.flyware.util.page.Page; +z9;BPw%
import org.flyware.util.page.PageUtil; ;2bG-v'4vO
eo,m ^&
import com.adt.bo.Result; 44S<(Re
import com.adt.dao.UserDAO; M,mj{OY~x
import com.adt.exception.ObjectNotFoundException; "-I>
import com.adt.service.UserManager; 5bMVDw/
6,oi(RAf
/** a2x2N_\=/D
* @author Joa ;r`[6[AG
*/ 9hLPo
publicclass UserManagerImpl implements UserManager { ;qzCoe
# Dy;x\a
private UserDAO userDAO; fC(lY4,H3R
s7&%_!4
/** u8o!ncy
* @param userDAO The userDAO to set. *D`,z3/*
*/ ~L 4"t_-
publicvoid setUserDAO(UserDAO userDAO){ qQVqS7 t
this.userDAO = userDAO; AbfLV942
} Url8Z\;aM
Te5_T&1Z
/* (non-Javadoc) `uGX/yQ#=
* @see com.adt.service.UserManager#listUser 7p2x}[ .\
9]hc{\
(org.flyware.util.page.Page) )_+#yaC
*/ c) 1m4SB@
public Result listUser(Page page)throws @ZT25CD
J }JT%SW
HibernateException, ObjectNotFoundException { 1R,n[`}h
int totalRecords = userDAO.getUserCount(); ty/jTo}
if(totalRecords == 0) \r<&7x#j
throw new ObjectNotFoundException ] niWRl
!fz`O>-mZ
("userNotExist"); oYOf<J
page = PageUtil.createPage(page, totalRecords); 9}3W0F;
List users = userDAO.getUserByPage(page); /$ L;m
returnnew Result(page, users); 1!=$3]l0Lj
} -4X,x
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} UVU}
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}S%a]
2]Y (<PC
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 !%5{jO1
1w\Y._jK
询,接下来编写UserDAO的代码: 5t0i/&zX
3. UserDAO 和 UserDAOImpl: c*6o{x}K
java代码:
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ztb2Ign<
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/*Created on 2005-7-15*/ l<v/T
package com.adt.dao; G::6?+S
g]jtVQH']
import java.util.List; kqHh@]Z0'
Zwq
uS9
import org.flyware.util.page.Page; 8l)l9;4 6
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import net.sf.hibernate.HibernateException; E8IWHh_
+Cau/sPXL
/** 0&EX-DbV
* @author Joa n>iPAD
*/ ^hbh|Du
publicinterface UserDAO extends BaseDAO { )?4m}
u1nv'\*
publicList getUserByName(String name)throws c~c3;
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HibernateException; $H5PB' b
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publicint getUserCount()throws HibernateException; 6"%[s@C
e {c.4'q
publicList getUserByPage(Page page)throws #|$7. e
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HibernateException; hvpn=0@M
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} faJ5f.
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Y!Z@1V`
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java代码: (EohxLl !p
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q
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/*Created on 2005-7-15*/ rj{'X /
package com.adt.dao.impl; hO(HwG?8t
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import java.util.List; <{cPa\
u1<xt1K
import org.flyware.util.page.Page; $_)f|\s
<[pU rJfTr
import net.sf.hibernate.HibernateException; d$Mj5wN:q
import net.sf.hibernate.Query; zpa'G1v
X\$M _b>O
import com.adt.dao.UserDAO; Jg%sl&65
t?c*(?Xa
/** r#{lpF,3Ib
* @author Joa V-X n&s
*/ MvRuW:
public class UserDAOImpl extends BaseDAOHibernateImpl *|` ' L
X;}_[=-
implements UserDAO { sI^1c$sBN
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/* (non-Javadoc) =%RDT9T.
* @see com.adt.dao.UserDAO#getUserByName Y ,}p
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(java.lang.String) "4r5 n8
*/ 3a#!^G!~
publicList getUserByName(String name)throws Rl S=^}>
Q"Bgr&RJ
HibernateException { M)b`~|Wt
String querySentence = "FROM user in class ? th+~dE
- '8|D!>v2
com.adt.po.User WHERE user.name=:name"; uAJ_`o[
Query query = getSession().createQuery C-2n2OM.
~" $9auQtC
(querySentence); ,fYO>l';`f
query.setParameter("name", name); f0hi70\(X
return query.list(); m7 !l3W2
} J4co@=AJ
B3yn:=80
/* (non-Javadoc) "=
%-
* @see com.adt.dao.UserDAO#getUserCount() %Z}dY~:
*/ WcUeWGC>
publicint getUserCount()throws HibernateException { E+3~w?1
int count = 0; Pb~S{):
String querySentence = "SELECT count(*) FROM 5hDE&hp
*Pq`~W_M7
user in class com.adt.po.User"; >#8`Zy:/Y
Query query = getSession().createQuery 1 9)78kV{
Q!|71{5U
(querySentence); /
Sp+MB9
count = ((Integer)query.iterate().next pkM32v-
!BQ!]u
()).intValue(); ;eA~z"g
return count; j}ruXg
} vhUuf+P*
(d!vm\-PH
/* (non-Javadoc) >|rL0
* @see com.adt.dao.UserDAO#getUserByPage ^Cak/5^K
LLU>c]a
(org.flyware.util.page.Page) d3 N %V.w
*/ 5aWKyXBIx
publicList getUserByPage(Page page)throws z&-`<uV~
h?CNChRJs
HibernateException { t8^*s<O
String querySentence = "FROM user in class 9(B)
'dht5iI;Yw
com.adt.po.User"; oiR`\uY
Query query = getSession().createQuery v=W%|iZ
+B&FZ4'
(querySentence); G-:DMjvN
query.setFirstResult(page.getBeginIndex()) WK<pZ *x
.setMaxResults(page.getEveryPage()); GvVuF S>y
return query.list(); YE-kdzff
} Dk7"#q@kx
E3KPjK
} |0Zj/1<$
+~[19'GH
z?i82B[Tm
@lBH@HR=C
%ZZ}TUI W
至此,一个完整的分页程序完成。前台的只需要调用 3Yr
+
6}FUi!"e
userManager.listUser(page)即可得到一个Page对象和结果集对象 0\i&