Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 &oJ[ *pQ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Xk:3w,
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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 VX<L
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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 .b!HEi<F
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分页支持类: hYA1N&yz@
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java代码: : Q2=t!
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package com.javaeye.common.util; hY *^rY'
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import java.util.List; 0C"2?etMx
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publicclass PaginationSupport { . S;o#Zw*R
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publicfinalstaticint PAGESIZE = 30; ADP3Nic
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privateint pageSize = PAGESIZE; W'E3_dj+
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privateList items; Tc/<b2\g
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privateint totalCount; :9q|<[Y^
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privateint[] indexes = newint[0]; xa
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privateint startIndex = 0; !wKNYe
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public PaginationSupport(List items, int >>;He7
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totalCount){ v0;dk(
setPageSize(PAGESIZE); An,TunX
setTotalCount(totalCount); .Rb1%1bdc
setItems(items); N>g6KgX{K
setStartIndex(0); =BV_?
} s%m?Yh3
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public PaginationSupport(List items, int mM+^v[=
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totalCount, int startIndex){ NID2$ p
setPageSize(PAGESIZE); BHNJH
setTotalCount(totalCount); {n<1uh9~$8
setItems(items); UD5hk
setStartIndex(startIndex); |h((SreO
} *Ct
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public PaginationSupport(List items, int a+9_sUq
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totalCount, int pageSize, int startIndex){ wLg@BSC.
setPageSize(pageSize); Y]B9*^d<
setTotalCount(totalCount); q'Y)Y(d
setItems(items); u=#_8e(9Z
setStartIndex(startIndex); 9/R=_y-
} 4s <ZKU
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publicList getItems(){ m8gU8a"(
return items; O"RIY3m
} ]*{tno
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publicvoid setItems(List items){ =;?Maexp3$
this.items = items; x51xY$M
} H4M`^r@)'
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publicint getPageSize(){ q _:7uQ
return pageSize; )Q|sW+AF
} )G#O# Yy
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publicvoid setPageSize(int pageSize){ y99|V39'
this.pageSize = pageSize; Xcg+ SOB
} Xupwh5G2
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publicint getTotalCount(){ !\\1#:*_W
return totalCount; |~Vq"6`
} &iJvkt
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publicvoid setTotalCount(int totalCount){ S3c%</'
if(totalCount > 0){ ? 8S~R
this.totalCount = totalCount; DM(c :+K-
int count = totalCount / r#6djs1
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pageSize; LcHe5Bv%
if(totalCount % pageSize > 0) Wr4Ob*2iD
count++; SMA' VU
indexes = newint[count]; wPJA+
for(int i = 0; i < count; i++){ 1f2*S$[*L
indexes = pageSize * i| *r/
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i; !Bhs8eGr3
} #[~f 6s9D
}else{ }SS~uQ;8
this.totalCount = 0; ,mt=)Ac
} "Y=4Y;5q
} 3rx8"
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publicint[] getIndexes(){ !q^2| %
return indexes; A$::|2~
} ;7mE%1X
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publicvoid setIndexes(int[] indexes){ PD:lI]:s
this.indexes = indexes; m=^ihQ
} X`k#/~+0
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publicint getStartIndex(){ qu/b:P
return startIndex; vUJQ<D
} @dvb%A&Pur
}#` -mRaU
publicvoid setStartIndex(int startIndex){ g+KuK`\N%
if(totalCount <= 0) WiF6*]oI
this.startIndex = 0; V_=7q=9mV
elseif(startIndex >= totalCount) p8E6_%Rw
this.startIndex = indexes Twk,R. O
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[indexes.length - 1]; xG,L*3c{o
elseif(startIndex < 0) tI+P&L"
this.startIndex = 0; I@I-QiI
else{ -1]8f
this.startIndex = indexes 5R*55@)
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[startIndex / pageSize]; j g(cpo d
} +J2;6t
} T<u QhPMw
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publicint getNextIndex(){ 0G#s/u#
int nextIndex = getStartIndex() + "jP{m;p
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pageSize; `4t*H>:y
if(nextIndex >= totalCount) 5uL!Ae
return getStartIndex(); $1bzsB|^
else 0M;aTM
return nextIndex; <;zcz[~
} dZ,~yV
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publicint getPreviousIndex(){ Xm~N Bt
int previousIndex = getStartIndex() - %j;mDR95
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pageSize; E:$r" oS
if(previousIndex < 0) OF 1Qr bj
return0; 4+B
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else ^ZDpG2(zk
return previousIndex; QlH,-]N$L
} d0G d5%
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} /"7_75
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抽象业务类 ^:^8M4:
java代码: :<R"Kk@
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/** C{FE*@U.
* Created on 2005-7-12 !2]'S=Y
*/ })5I/
package com.javaeye.common.business; Ydh+iLjhx
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import java.io.Serializable; 7H_*1_%ZQ
import java.util.List; xtX`3=s
yMK VF`D*
import org.hibernate.Criteria; kZ<"hsh,Y'
import org.hibernate.HibernateException; >
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import org.hibernate.Session; V})b.\"F
import org.hibernate.criterion.DetachedCriteria; 1\%2@NR
import org.hibernate.criterion.Projections; 1YvE/<6
import L(_bf/@3
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org.springframework.orm.hibernate3.HibernateCallback; Pfl8x
import #0 eop>O
"\l#q$1h
org.springframework.orm.hibernate3.support.HibernateDaoS nlR7V.
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upport; =4:]V\o):'
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import com.javaeye.common.util.PaginationSupport; 1'BC
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public abstract class AbstractManager extends ) 0|X];sD
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HibernateDaoSupport { [IPXU9&Q
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privateboolean cacheQueries = false; ,p9>/)l
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privateString queryCacheRegion; R9)"%SO<y
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publicvoid setCacheQueries(boolean V8"m_
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cacheQueries){ l1ViUY&Z
this.cacheQueries = cacheQueries; tIL ]JB
} }MW+K&sIh
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publicvoid setQueryCacheRegion(String GfL:0
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queryCacheRegion){ ,]_<8@R
this.queryCacheRegion = p\ _&
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queryCacheRegion; ,HtXD~N
} 3D2i32Y@!
}C<$q
publicvoid save(finalObject entity){ 9UE)4*5
getHibernateTemplate().save(entity); 7~m[:Eg6[s
} 7'idjcR
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publicvoid persist(finalObject entity){ 1Y(NxC0P=g
getHibernateTemplate().save(entity); ){$*<#&H
} {&0u:
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publicvoid update(finalObject entity){ VrnZrQj<
getHibernateTemplate().update(entity); ]lZg }7h
} l3HfaCP6:
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publicvoid delete(finalObject entity){ "-:-!1;Ji
getHibernateTemplate().delete(entity); fOt?2Bh
} Ln"D .gpq
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publicObject load(finalClass entity, ZFNg+H/k
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finalSerializable id){ ;U]Ym48
return getHibernateTemplate().load *dPG[ }
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(entity, id); f yhBfA:u
} [SU;U['7
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publicObject get(finalClass entity, .0?A0D?sP
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finalSerializable id){ uG=~kO
return getHibernateTemplate().get ~+CEek
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(entity, id); YWF Hv@
} ,C}s8|@k
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publicList findAll(finalClass entity){ <
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return getHibernateTemplate().find("from ;2[o>73F
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" + entity.getName()); HJjx!7h
} =;~*YD(%/
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publicList findByNamedQuery(finalString g<g$c<sm
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namedQuery){ (Q}ByX
return getHibernateTemplate usR+ZQaA
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().findByNamedQuery(namedQuery); "2z&9`VIY
} a7n`(}?Y
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publicList findByNamedQuery(finalString query, n.OsmCR N;
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finalObject parameter){ __|Y59J%
return getHibernateTemplate bkFO4OZd
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().findByNamedQuery(query, parameter); .,<w_=
} q0 L\{
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publicList findByNamedQuery(finalString query, W:JR\KKU
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finalObject[] parameters){ N^4CA@'{
return getHibernateTemplate xiOAj"}~
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().findByNamedQuery(query, parameters); Q PrP3DK
} )>,ndKT~
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publicList find(finalString query){ C2H2*"
return getHibernateTemplate().find W#kd[Wi
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(query); $g_|U:,
} %\T#Ik~3
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publicList find(finalString query, finalObject
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< b-OdOg
parameter){ |cgc^S/~H
return getHibernateTemplate().find +h@ZnFp3
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(query, parameter); DO6
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} xM=?ES
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public PaginationSupport findPageByCriteria QXEz[R
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(final DetachedCriteria detachedCriteria){ !GnwE
return findPageByCriteria g[N3jt@
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); QYc/f"9
} W:hTRq
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public PaginationSupport findPageByCriteria lUd4`r"
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(final DetachedCriteria detachedCriteria, finalint $kc cM&B
)v\ A8)[
startIndex){ T_[
return findPageByCriteria NZz^* Ela
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(detachedCriteria, PaginationSupport.PAGESIZE, <l5s[
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startIndex); 80K"u[
} -ufaV#
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public PaginationSupport findPageByCriteria PLq]\y
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(final DetachedCriteria detachedCriteria, finalint AnoA5H
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pageSize, )j!%`g
finalint startIndex){ Q w)U
return(PaginationSupport) L@.Trso
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getHibernateTemplate().execute(new HibernateCallback(){ d2fiPI7lg
publicObject doInHibernate ;@qQ^!g2
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(Session session)throws HibernateException { is=x6G*r
Criteria criteria = 5Gm8U"UR
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detachedCriteria.getExecutableCriteria(session); q"Sja!-;|
int totalCount = pnUL+UYeM
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((Integer) criteria.setProjection(Projections.rowCount ']N\y6=fn9
9M-W 1prb
()).uniqueResult()).intValue(); ,/Q`gRBh"
criteria.setProjection hqa6aYY x
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(null); Zt}b}Bz
List items = P| ftEF
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criteria.setFirstResult(startIndex).setMaxResults 9Y?``QBN
5%+epzy
(pageSize).list(); E {UhM q7
PaginationSupport ps = .
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new PaginationSupport(items, totalCount, pageSize, DABV}@ K"
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startIndex); {vk%&{D0)
return ps; nfh<3v|kvR
} !QCErE;r
}, true); h6?o)Q>N
} pZ]&M@Ijp
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public List findAllByCriteria(final xl Q]"sm1
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DetachedCriteria detachedCriteria){ !Ej?9LHo
return(List) getHibernateTemplate [LrO"9q(
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().execute(new HibernateCallback(){ iLN O}EUL
publicObject doInHibernate O^8=Xj#}
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(Session session)throws HibernateException { 7!;zkou
Criteria criteria = V P(JV
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detachedCriteria.getExecutableCriteria(session); 2InM(p7j~K
return criteria.list(); *+(eH#_2/
} .g94|P
}, true); _#we1m
} js!C`]1
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public int getCountByCriteria(final }GHCu
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DetachedCriteria detachedCriteria){ 3Kq/V_
Integer count = (Integer) ru|*xNXKgC
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getHibernateTemplate().execute(new HibernateCallback(){ ED);2*qP}
publicObject doInHibernate \+&)9 !K
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(Session session)throws HibernateException { UzW]kY[A<
Criteria criteria = =CO'LyG
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detachedCriteria.getExecutableCriteria(session); c4zGQoeH:
return olKM0K
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criteria.setProjection(Projections.rowCount 3J8M0W
/. H(&
()).uniqueResult(); Ucz=\dO1
} }PM7CZSq
}, true); 5W=Jn?y2
return count.intValue(); yCkX+{ki
} P 6({wx
} 7~;)N$d\
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用户在web层构造查询条件detachedCriteria,和可选的 qyh]v [
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 nzF2Waa-
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PaginationSupport的实例ps。 =5:S"WNj
7 4&{GCL
ps.getItems()得到已分页好的结果集 -9Ygn_M
ps.getIndexes()得到分页索引的数组 aj=-^iGG
ps.getTotalCount()得到总结果数 BkY#wJ'
ps.getStartIndex()当前分页索引 ab#z&jg!
ps.getNextIndex()下一页索引 BB_(!omq[
ps.getPreviousIndex()上一页索引 OX?E3 <8`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4n1 g@A=y
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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 N8=-=]0G
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O
一下代码重构了。 /c6]DQ<?
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我把原本我的做法也提供出来供大家讨论吧: 8VuLL<\|
0k4XVd+Nv
首先,为了实现分页查询,我封装了一个Page类: cl |}0Q5
java代码: IRTWmT
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/*Created on 2005-4-14*/ >/NegJh'F}
package org.flyware.util.page; .~TI%
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/** 3+q-yP#X
* @author Joa A,(9|#%L
* r;E5e]w*-
*/ V#R; -C
publicclass Page { ZI8@ 6 L\
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/** imply if the page has previous page */ Mm1>g~o
privateboolean hasPrePage; s6#e?5J
Ps;4 ]=c
/** imply if the page has next page */ N/<c;"o
privateboolean hasNextPage; _H-Fm$Q
PO^#G@
/** the number of every page */ rq\<zx]au
privateint everyPage; UUa@7|x
K$B~vy6E`
/** the total page number */ 66$hdT$
privateint totalPage; DF'~ #G8
5+j):_
/** the number of current page */ 4 /v[.5
privateint currentPage; ~QUN O~
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/** the begin index of the records by the current kuq&; uk$Q
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query */ >%slzr
privateint beginIndex; }o\} qu*
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/** The default constructor */ HiD%BL>%
public Page(){ 91DevizXx
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} Xg\unUHa
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/** construct the page by everyPage .Yz^r?3t
* @param everyPage /zr)9LQY0
* */ _a_T`fE&de
public Page(int everyPage){ ;ZMIYFXRqh
this.everyPage = everyPage; P{Q$(rOe
} *i!t&s
1u(n[<WtT_
/** The whole constructor */ {Z
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public Page(boolean hasPrePage, boolean hasNextPage, IGab~`c-[
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int everyPage, int totalPage, MmFtG-
int currentPage, int beginIndex){ #&?}h)Jr'
this.hasPrePage = hasPrePage; 4r86@^c*
this.hasNextPage = hasNextPage; _'^_9u G
this.everyPage = everyPage; g_?Q3
this.totalPage = totalPage; )n[=)"rf
this.currentPage = currentPage; DbtkWq%
this.beginIndex = beginIndex; 6\.LG4@LO
} \'|t>|zhp
n-,mC/4
/** }wI+eMr
* @return $ub0$S/Hu
* Returns the beginIndex. VN$7r
*/ YkFERIa076
publicint getBeginIndex(){ ,p!IFS`
return beginIndex; &l4kwds R
} Uv~|Xj4.
mHJGpJ=a-
/** $1Wb`$
* @param beginIndex 5fz
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* The beginIndex to set.
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*/ AVfF<E/
publicvoid setBeginIndex(int beginIndex){ F
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this.beginIndex = beginIndex; Y]5MM:mI
} WMWUP ZsGS
fvV"H{V,
/** >;VZB/d
* @return #q-fRZ:P
* Returns the currentPage. TefPxvd
*/ /s+S\
djk
publicint getCurrentPage(){ -"^xg"
return currentPage; 6Tc!=lk
} E}<i?;
~&+ a.@T
/** (.L?sDQ</z
* @param currentPage >p" U|
* The currentPage to set. oq|`;k
*/ _A0X[}^K
publicvoid setCurrentPage(int currentPage){ nE2?3 S>
this.currentPage = currentPage; BN&}g}N
} |ZXz&Xor
"=JE12=u
/** /FC(d5I
* @return FJxb!-0&
* Returns the everyPage. 7KJ0>0~Et
*/ ={;+0Wjb8
publicint getEveryPage(){ m}S}fH(
return everyPage; W5~!)Ec
} :_ =YH+bZ
X|QokAR{$>
/** .])X.7@x
* @param everyPage :VLYF$|
* The everyPage to set. Q/*|ADoq
*/ 1+Ik\
publicvoid setEveryPage(int everyPage){ VUz+_)
this.everyPage = everyPage; FN (O
} -(ST
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/** tF./Jx]_
* @return 9\=SG"e(
* Returns the hasNextPage. cqW(9A|8
*/ ZPz=\^
publicboolean getHasNextPage(){ NzeiGj
return hasNextPage; Y]uVA`%"b
} vF>]9sMv
(A=Z,ed
/** $H]NC-\+>
* @param hasNextPage aygK$.wos
* The hasNextPage to set. cRNVqMpg
*/ GdrVH,j
publicvoid setHasNextPage(boolean hasNextPage){ S2W@;XvV
this.hasNextPage = hasNextPage; ^\Q%VTM
} ZvO1=*
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/** W/CZ/Mc
* @return W
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* Returns the hasPrePage. y7GgTC/H
*/ N|ZGc{?
publicboolean getHasPrePage(){ ?8U]UM6Tu4
return hasPrePage; OjqT5<U
} EQ|Wke
L.}sN.
/** Kxz|0l
* @param hasPrePage ~ tN/
* The hasPrePage to set. BglbQ'6p
*/ {y%@1q%"
publicvoid setHasPrePage(boolean hasPrePage){ 5@I/+D
this.hasPrePage = hasPrePage; "}H2dn2n
} a0Fq$
-%{+\x2
/** 9U=6l]Np
* @return Returns the totalPage. =A$d)&
* cR*~JwC:
*/ AEElaq.B
publicint getTotalPage(){ ,068IEs
return totalPage; + ef>ek
} nNnfcA&W
=En1?3?
/** xe3Jxo!U
* @param totalPage !T8sWMY
* The totalPage to set. 1rLxF{,
*/ #YK3Ogb,
publicvoid setTotalPage(int totalPage){ d 3#e7rQ8
this.totalPage = totalPage; {SRD\&J[
} fE3%$M[V7
8LXK3D}?3
} )V*`(dn'zm
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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 }_@p`>|)rB
-9o7a_Z
个PageUtil,负责对Page对象进行构造: 1F3Q^3+
java代码: 2k&Voa
Pt-O1$C[
aYWUwYB$
/*Created on 2005-4-14*/ wqJl[~O$
package org.flyware.util.page; pE X Q
1&9w]\Ae7l
import org.apache.commons.logging.Log; wByTNA7
import org.apache.commons.logging.LogFactory; 6VJS
l%X
40dwp*/!
/** D>Rlm,U
* @author Joa '- #QK'p
* G-sQL'L[U
*/ A* Pz-z>z
publicclass PageUtil { D*sL&Rt][Y
nHp$5|r<
privatestaticfinal Log logger = LogFactory.getLog |Z+qaq{X
%P(2uesd
(PageUtil.class); Py/~Q-8p
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/** t3K9 |8<
* Use the origin page to create a new page (*V!V3E3#
* @param page ]6O(r)k
* @param totalRecords yF+mJ >kj
* @return ZW@cw}
*/ Ol|fdQ
publicstatic Page createPage(Page page, int CLJn+Y2
4p6T0II_$
totalRecords){ M&H,`gm
return createPage(page.getEveryPage(), ocp
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page.getCurrentPage(), totalRecords); t\Qm2Q)>
} LCq1F(q
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8 y<}
/** =5YbK1Q^
* the basic page utils not including exception jX*gw6!
+[$Td%6
handler jyidNPLm4
* @param everyPage w"O;: `|n
* @param currentPage |tTcJ\bG
* @param totalRecords &4l!2
* @return page [MKt\(
*/ +"~*L,ken0
publicstatic Page createPage(int everyPage, int 0 wDhX
w]V684[>
currentPage, int totalRecords){ G9K& }_,
everyPage = getEveryPage(everyPage); >enP~uW[#
currentPage = getCurrentPage(currentPage); ,_=LV
int beginIndex = getBeginIndex(everyPage, Z^mQb2e.
/BhP`a%2Q
currentPage); IMpL+W.
int totalPage = getTotalPage(everyPage, Ke~!1S8=
)M(//jX
totalRecords); ~*Y/#kPY
boolean hasNextPage = hasNextPage(currentPage, !<b+7A
O-P`HKr
totalPage); ![MtJo5
boolean hasPrePage = hasPrePage(currentPage); .G"T;w6d
tq=M 9c
returnnew Page(hasPrePage, hasNextPage, WE-+WC!!:
everyPage, totalPage, w7vQ6jkH
currentPage, -Y N(j\
!vHCftKel
beginIndex); Hd
gABIuX
} :?i,!0#"
F*NHy.Y
privatestaticint getEveryPage(int everyPage){ %?8.UW\m
return everyPage == 0 ? 10 : everyPage; fWDTP|DV
} gT,iH.
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privatestaticint getCurrentPage(int currentPage){ y
S<&d#:"
return currentPage == 0 ? 1 : currentPage; q 1u_r
} >N}+O<Fc
<xH!
Yskc
privatestaticint getBeginIndex(int everyPage, int s9fEx-!y
v`:!$U*
H=
currentPage){ .cmhi3o4
return(currentPage - 1) * everyPage; AU9:Gu@M/
} '[HU!8F
n:H
|=SF{
privatestaticint getTotalPage(int everyPage, int %z"$?Iv
kb~ 9/)~g
totalRecords){ kY'C'9p
int totalPage = 0; hl DU.k
$d&7q5[
if(totalRecords % everyPage == 0) 9,"gXsvx(
totalPage = totalRecords / everyPage; 7~QAprwVS
else ]2|KG3t
totalPage = totalRecords / everyPage + 1 ; 4]Gm4zO
-;i:bE
return totalPage; F>%,}Y~B:
} 2<V`
gxC`Ml
privatestaticboolean hasPrePage(int currentPage){ :z|$K^)7Z
return currentPage == 1 ? false : true; W4h ]4X
} sp0_f;bC
)_?H BTG
privatestaticboolean hasNextPage(int currentPage, UCo<ie\V
b8$%=Xp
int totalPage){ 1WY$Vs
return currentPage == totalPage || totalPage == VwXR,(
'l-VWqR-
0 ? false : true; ?4R q +
} LVL#qNIu
piIGSC
(?.h<v1}
} EvA8<o
" ;\EU4R
+hH7|:JQ
&@PAv5iNf
iA'p!l|P
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。 'p%w_VbI
90wnwz
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 s;tI?kR>%
DnF|wS
做法如下: -YipPo"a
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0-d&R@lX.
1d&Q
E\2}
的信息,和一个结果集List: qs9r$o.\l
java代码: ~BBh 4t&
V9
EC@)
NpA%7Q~B$,
/*Created on 2005-6-13*/ NpGz y`&b
package com.adt.bo; |m$]I4Jr
PK_2
import java.util.List; Y)M-?|4
Ow-;WO_HQ
import org.flyware.util.page.Page; 4!?4Tc!X
a4q02 cV
/** &kH7_Lz
* @author Joa oL9ELtb]s
*/ Kf6D$}
publicclass Result { S7R*R}
UK[+I]I
p
private Page page; `_J>R
t*c_70|@k
private List content; HLE%f;
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/** (W9 K:]}
* The default constructor 7?
="{;
*/ mVT[:a3
public Result(){ DuC_uNJ
super(); RF\h69]:I
} SMQC/t]HT
$@WA}\D
/** n+Ng7
* The constructor using fields OoZv\"}!_
* g_"B:DR
* @param page J^pq<
* @param content F}5skD=
*/ %V-Hy ;V
public Result(Page page, List content){ C{V,=Fo^
this.page = page; ;9uDV-"
this.content = content; }7qboUG e
} U(<~("ocN
xp"F)6
/** H.[(`wi!I
* @return Returns the content. pJQ_G`E
*/ ip*UujmNyR
publicList getContent(){ cs]3Rp^g
return content; R~#&xfMd.
} ]TsmW ob
2]tW&y_i
/** AxCFZf 5
* @return Returns the page. asbFNJG{
*/ 6N.MCB^
public Page getPage(){ *+J`Yk7}
return page; O+~@S~
} \Oe8h#%
' KNg;
/** 4}<[4]f?|
* @param content /8lmNA
* The content to set. B)qcu'>iy
*/ ;]%Syrzp
public void setContent(List content){ 4uv*F:eo
this.content = content; 74KR.ABd
} Z%VgAV>>
s>ZlW:jY
/** XeAH.i<
* @param page rX|{nb
* The page to set. Ys@\~?ym+
*/ e~$aJO@B.R
publicvoid setPage(Page page){ /,ISx}
this.page = page; N9O}6
} mFBuKp+0)h
} ,.uI>
m$$sNPnT
%D+NrL(
XC,by&nY<y
%lGg}9k'
2. 编写业务逻辑接口,并实现它(UserManager, ^=w){]G
5^36nEoA(
UserManagerImpl) F\+!\b*lP
java代码: 4?aNJyV%&
a &hj|
#:[CF:
/*Created on 2005-7-15*/ 9:*a9xT,
package com.adt.service; 12 bztlv
{
b7%Zd3-
import net.sf.hibernate.HibernateException; D(Q=EdlO
)AAPT7!U
import org.flyware.util.page.Page; 6W N(Tw
0C0ld!>r
import com.adt.bo.Result; ~*RBMHs
l>@){zxL
/** j.29nJ
* @author Joa ;QQ/bM&I
*/ sW@_q8lG
publicinterface UserManager { xGK"`\V
C*Dco{
EQ>
public Result listUser(Page page)throws 8s6^!e&
lJU]sZ9~b
HibernateException; cb _nlG!
IjRUL/\=
} VOrBNu
?qczMck_
|Q#CQz
6b h.5|
\l/<[ZZ
java代码: +Pb@@C&
l gTw>r
n`|CDKb
/*Created on 2005-7-15*/ ?4lEHef
package com.adt.service.impl; bU_P@GKB
S| l%JM^
import java.util.List; x7c#kU2A&Z
#h2 qrX&+
import net.sf.hibernate.HibernateException; .&n;S';"
lAPPng`
import org.flyware.util.page.Page; =b#,OXQ
import org.flyware.util.page.PageUtil; s^-o_K\*c
e1 P(-V
import com.adt.bo.Result; =tqChw
import com.adt.dao.UserDAO; (l:LG"sy\
import com.adt.exception.ObjectNotFoundException; \Oa11c`6
import com.adt.service.UserManager; .\|}5J9W
{tF)%>\#
/** e&F=w`F\
* @author Joa >Gr,!yP
*/ RVa{%
publicclass UserManagerImpl implements UserManager { EdS7m,d
Hr;\}
private UserDAO userDAO; ~{np G
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/** Hc-Ke1+
* @param userDAO The userDAO to set. &^])iG,Ew
*/ MK, $#
publicvoid setUserDAO(UserDAO userDAO){ kr5'a:F)
this.userDAO = userDAO; %CG=mTP
} *&rV}vVP^
Mt(;7q@1c
/* (non-Javadoc) 87:V-*8
* @see com.adt.service.UserManager#listUser B7nm7[V
Ct9*T`Gl
(org.flyware.util.page.Page) j79$/ Ol
*/ oJVpJA0IA
public Result listUser(Page page)throws t3;QF
Hp-vBoEk
HibernateException, ObjectNotFoundException { hrTl:\
int totalRecords = userDAO.getUserCount(); @z7$1pl}
if(totalRecords == 0) d8/KTl
throw new ObjectNotFoundException (KdP^.7
Z}$1~uyw
("userNotExist"); +cx(Q(HD\
page = PageUtil.createPage(page, totalRecords); 2)jf~!o)Z
List users = userDAO.getUserByPage(page); MHAWnH8
returnnew Result(page, users); #i[V{J8.p
} MD=!a5'
cW\Y1=Gv|
} &%` 0&y
M0"}>`1lJ
SI/p8 ^
T+)#Du
aUEnQ%YU"
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 NC{8[*Kx5
hZeF? G)L'
询,接下来编写UserDAO的代码: (/3E,6gMk^
3. UserDAO 和 UserDAOImpl: 6yXMre)YV
java代码: Mg=R**s1x%
f&`yiy_
8Z(\iZ5Rgj
/*Created on 2005-7-15*/ EY'48S
package com.adt.dao; 5tm:|.`SQ
-Oc
import java.util.List; lhduK4u
qre(3,VE5
import org.flyware.util.page.Page; IyGW>g6_.
_&/2-3]\B
import net.sf.hibernate.HibernateException; 6eAJ>9@x
=FXq=x%9+
/** @!2vS@f
* @author Joa yo"!C?82=
*/ XFWo"%}w
publicinterface UserDAO extends BaseDAO { mA0|W#NB
-3&mgd
publicList getUserByName(String name)throws +{"w5o<CO
wVtBH_>
HibernateException; lyQNE3
%pr}Xs(-f
publicint getUserCount()throws HibernateException; h9WyQl7
#]FJx
publicList getUserByPage(Page page)throws ~X%W2N2
zc%HBZ3p
HibernateException; BZAF;j
u4.2u}A/R%
} u1_NC;
2, r{zJ8
@w@ `-1
5u&hp
vON1\$bu`
java代码: _$BH.I
"BD$-]
95hdQ<W
/*Created on 2005-7-15*/ ]{PJ
package com.adt.dao.impl; QN OA66
e[*%tx H
import java.util.List; ^fxS=Qs+
^DOQ+
import org.flyware.util.page.Page; |n+
`t?L^
A6%~+9
import net.sf.hibernate.HibernateException; C#D8
E.W
import net.sf.hibernate.Query; x] j&Knli
l6k.`1.In
import com.adt.dao.UserDAO; _Q6` Wp6m
a&s&6Q|Y
/** UA}N
* @author Joa pm k;5 d
*/ fD ?w!7f-1
public class UserDAOImpl extends BaseDAOHibernateImpl p28=l5y+
1i:Q
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F
implements UserDAO { [-'LJG Wb<
f,QBj{M,
/* (non-Javadoc) K1[(%<Gp
* @see com.adt.dao.UserDAO#getUserByName +n&9ZCH
6T ,'Oz
(java.lang.String) S7WT`2
*/ =X}s^KbI{
publicList getUserByName(String name)throws AG(Gtvw
#CTHCwYo
HibernateException { b 3i34,
String querySentence = "FROM user in class Q9NKQuSu
"%]vSr
com.adt.po.User WHERE user.name=:name"; { K*
Query query = getSession().createQuery LP:F'Q:<
$V2.@X
(querySentence); ?-D'xqc
query.setParameter("name", name); N(=\S:
return query.list(); );oE^3]f
} *ci%c^}V
d td}P~
/* (non-Javadoc) 5;Q9Z1
`
* @see com.adt.dao.UserDAO#getUserCount() (|U|>@
*/ dId&tTMmC
publicint getUserCount()throws HibernateException { `sPH7^R
int count = 0; ewORb
String querySentence = "SELECT count(*) FROM 4+'d">+|
jRYW3a_7
user in class com.adt.po.User"; .rs\%M|X
Query query = getSession().createQuery /w2jlu}yt
2<33BBlWA
(querySentence); {}1KI+s9\
count = ((Integer)query.iterate().next qjI.Sr70
{axMS yp;
()).intValue(); $3je+=ER
return count; 0>)F+QC
} gL}x|Q2`
}Z3+z@L
/* (non-Javadoc) *#g[
jl4
* @see com.adt.dao.UserDAO#getUserByPage Z@ZSn0
\:|"qk
(org.flyware.util.page.Page) @w{"6xc%a
*/ &JHqUVs^
publicList getUserByPage(Page page)throws 2V)qnMxAZJ
j2%?-(U
HibernateException { Os"T,`F2s
String querySentence = "FROM user in class !@wG22iC4d
#xBh62yIuP
com.adt.po.User"; ~;P>}|6Y
Query query = getSession().createQuery 8xQjJ
K6M_b?XekA
(querySentence); a<d$P*I(cH
query.setFirstResult(page.getBeginIndex()) u[~= a5:4
.setMaxResults(page.getEveryPage()); atmTI`i
return query.list(); 3}ATt".
} o=ULo &9
P[<EFjE
} &