Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 C7S\4rDJ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 KFbB}oId
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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 ;(?tlFc
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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 6 ]x?2P%
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分页支持类: Sy VGm@
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java代码: yIL=jzm`7
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package com.javaeye.common.util; r+ bGZ
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import java.util.List; ."+lij=56
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publicclass PaginationSupport { rk8pL[|
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publicfinalstaticint PAGESIZE = 30; X6cn8ak3
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privateint pageSize = PAGESIZE; p{L;)WTI
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privateList items; 8Nzn%0(Q
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privateint totalCount; w!"L\QT
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privateint[] indexes = newint[0]; :dt[ #
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privateint startIndex = 0; R@K\
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public PaginationSupport(List items, int 2?~nA2+vm
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totalCount){ aLh(8 ;$
setPageSize(PAGESIZE); U"7o;q
setTotalCount(totalCount); |3FI\F;^q
setItems(items); LWM<[8wJ4
setStartIndex(0); uU 7 <8G
} ^i8,9T'=
{}$rN@OM$
public PaginationSupport(List items, int ]Uwp\2Bc
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totalCount, int startIndex){ \>5sW8P]H`
setPageSize(PAGESIZE); ]00 so`
setTotalCount(totalCount); ` &A`&-nc=
setItems(items); 5}G_2<G
setStartIndex(startIndex); &`qYe)1Eo
} !kSemDC
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public PaginationSupport(List items, int 9Vm
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)(]rUJ~+~A
totalCount, int pageSize, int startIndex){ %d+Fq=<
setPageSize(pageSize); 9^!.!%6O$
setTotalCount(totalCount); f4p*!e
setItems(items); $}(Z]z}O ;
setStartIndex(startIndex); US)i"l7:H*
} =u2~=t=LV
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publicList getItems(){ _9=87u0
return items; fc~fjtqwvz
} Y)k"KRW+
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publicvoid setItems(List items){ d[?RL&hJO
this.items = items; ;cVK2'
} Tp-W/YC
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publicint getPageSize(){ m u9,vH
return pageSize; >aJmRA-C}
} C1{Q 4(K%
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publicvoid setPageSize(int pageSize){ ;}6wj@8He
this.pageSize = pageSize; )$p36dWl
} n}Z%-w$K#
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publicint getTotalCount(){ }uMu8)Q
return totalCount; }N9PV/a
} P>q~ocq<
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publicvoid setTotalCount(int totalCount){ Lf9s'o}.R
if(totalCount > 0){ 7J3A]>qU
this.totalCount = totalCount; iJh{,0))g
int count = totalCount / |34k;l]E
n5"i'o{w
pageSize; \GHj_r
if(totalCount % pageSize > 0) d0T 8Cwcb
count++; 6DHZ,gWq
indexes = newint[count]; vV"YgN:
for(int i = 0; i < count; i++){ ~Q"qz<WO
indexes = pageSize * %J6>Vc!ix=
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i; YP!}Bf
} kK6t|Yn&
}else{ Zah<e6L
this.totalCount = 0; q !}~c
} t(UBs-t
} `!X8Cn
}`Wo(E}O
publicint[] getIndexes(){ k_1;YOBF
return indexes; ^VzhjKSu
} V,zFHXO
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publicvoid setIndexes(int[] indexes){ 43=)akJi
this.indexes = indexes; OtAAzc!dQ
} ??Urm[Y.Z
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publicint getStartIndex(){ Q-iBK*-w
return startIndex; ) F -8
} 2I suBX\[
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publicvoid setStartIndex(int startIndex){ ?W dY{;&
if(totalCount <= 0) ',+Zqog92
this.startIndex = 0; \0i0#Dt9
elseif(startIndex >= totalCount) SPe%9J+
this.startIndex = indexes Bvj
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[indexes.length - 1]; #$ka.Pj
elseif(startIndex < 0) ( ?e
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this.startIndex = 0; lP4s"8E`h
else{ a_VWgPVdDS
this.startIndex = indexes -j Nnx*
non5e)w3@
[startIndex / pageSize]; $BLd>gTzmv
} 1#|lt\T
} ~md06"AYJ
6 %` h2Z
publicint getNextIndex(){ QXa2qxTc
int nextIndex = getStartIndex() + 3k8nWT:wT
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pageSize; O#!|2qN
if(nextIndex >= totalCount) r|z B?9Q
return getStartIndex(); `.~*pT*u
else c<Ud[x.
return nextIndex; qm9=Ga5
} all2?neK
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publicint getPreviousIndex(){ P~&J@8)c
int previousIndex = getStartIndex() - A58P$#)?
z t
pageSize; Oku7&L1
if(previousIndex < 0) Q4L7{^[X
return0; EIpz-"S
else d|gfp:Z`a
return previousIndex; 1'\s7P
} 8F$]@0v`%
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} 6Xn9$C)
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抽象业务类 E2=vLI]
java代码: 3<1x>e2nT
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/** ssH[\i
* Created on 2005-7-12 "d0D8B7HI@
*/ @'Pay)P
package com.javaeye.common.business; xNRMI!yv
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import java.io.Serializable; (*T$:/zIS
import java.util.List; #oR@!?
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import org.hibernate.Criteria; [4yw? U
import org.hibernate.HibernateException; HRCnjem/v\
import org.hibernate.Session; <<Z, 1{3F
import org.hibernate.criterion.DetachedCriteria; ?O]RQXsZ2
import org.hibernate.criterion.Projections; M[u6+`
import m G+=0Rn^
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org.springframework.orm.hibernate3.HibernateCallback; 4#t-?5"
import {([`[7B>a<
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org.springframework.orm.hibernate3.support.HibernateDaoS &xt
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upport; ;Z`R!
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import com.javaeye.common.util.PaginationSupport; PY+4OZ$
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public abstract class AbstractManager extends _~F
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HibernateDaoSupport { L
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privateboolean cacheQueries = false; $ 1m}lXk
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privateString queryCacheRegion; )ac!@slb^7
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publicvoid setCacheQueries(boolean _]eyt_
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cacheQueries){ N\rL ~4/
this.cacheQueries = cacheQueries; MGre_=Dm_
} G68@(<<Z
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publicvoid setQueryCacheRegion(String k;qWiYMV
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queryCacheRegion){ f=S2O_Ee
this.queryCacheRegion = (qz)3Fa
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queryCacheRegion; 2. {/ls
} }Fox
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publicvoid save(finalObject entity){ $2-_j)+
getHibernateTemplate().save(entity); i` ay9J8N
} Wu8^Z Z{
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publicvoid persist(finalObject entity){ g=,}j]tl
getHibernateTemplate().save(entity); pUW7p
} 1xh7KBr,
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publicvoid update(finalObject entity){ .*.eY?,V
getHibernateTemplate().update(entity); {esb"beGLa
} |k,-]c;6
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publicvoid delete(finalObject entity){ fc[_~I'
getHibernateTemplate().delete(entity); n+i=Ff
} ,H^!G\
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publicObject load(finalClass entity, "^;h'
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finalSerializable id){ ~P;A
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return getHibernateTemplate().load ;-;lM6zP
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(entity, id); ik;F@kdm`
} ='m%Iq7X
?)(-_N&T
publicObject get(finalClass entity, 5NH4C
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finalSerializable id){ jIVD i~Ld
return getHibernateTemplate().get 3wcFR0f
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(entity, id); e?*Teb?R
} cUdS{K&K
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publicList findAll(finalClass entity){ A^A)arJS
return getHibernateTemplate().find("from %~gI+0HK
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" + entity.getName()); r\Kcg~D>
} =6"5kz10
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publicList findByNamedQuery(finalString F*r)
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namedQuery){ i. (Af$
return getHibernateTemplate 1?1Bz?EKF*
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().findByNamedQuery(namedQuery); :."oWqb)
} GQ>0E
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publicList findByNamedQuery(finalString query, ]dI^
S
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finalObject parameter){ X;Sb^c"j1
return getHibernateTemplate J p+'"a
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().findByNamedQuery(query, parameter); \=bKuP(it
} #kq!{5,
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publicList findByNamedQuery(finalString query, 4OpzGZ4+
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finalObject[] parameters){ UeLO `Ug0;
return getHibernateTemplate ,w H~.LHi
F P|cA^$<
().findByNamedQuery(query, parameters); *4}NLUVX
} f:<BUqa
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publicList find(finalString query){ E5M/XW\E6
return getHibernateTemplate().find `Hlf.>b1
t'@mUX:-A
(query); d(d<@cB9
} k:R\;l5
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publicList find(finalString query, finalObject ?X@[ibH6
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parameter){
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return getHibernateTemplate().find h72/03!
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(query, parameter); 1p$(\
} iC=>wrqY>
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public PaginationSupport findPageByCriteria )Ak#1w&q
}RI_k&;
(final DetachedCriteria detachedCriteria){ L%is"NZh
return findPageByCriteria a(]&H
"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~1wt=Ln>
} tjb$MW$('
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public PaginationSupport findPageByCriteria A%Ka)UU+n
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(final DetachedCriteria detachedCriteria, finalint aq}hlA(w
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startIndex){ eTvjo(Lvx
return findPageByCriteria 8xgBNQdPT
[1P_^.Htr
(detachedCriteria, PaginationSupport.PAGESIZE, ofQs
/
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startIndex); ISs&1`Y
} KYm8|]'g
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public PaginationSupport findPageByCriteria r*vh3.Agl
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(final DetachedCriteria detachedCriteria, finalint E4892B:`
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pageSize, M*gvYo
finalint startIndex){ )2?]c
return(PaginationSupport) NeY*l
y,x 2f%x
getHibernateTemplate().execute(new HibernateCallback(){ B+Qf?1f
publicObject doInHibernate e72Fz#<q
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(Session session)throws HibernateException { l%"DeRp,/
Criteria criteria = 5_E8
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detachedCriteria.getExecutableCriteria(session); q=5aHH% |
int totalCount = t"GnmeH
i
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((Integer) criteria.setProjection(Projections.rowCount m_/Ut
%"mI["{
()).uniqueResult()).intValue(); )
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criteria.setProjection yM@sGz6c!
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(null); azv173XZ
List items = /e>%yq<9B
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criteria.setFirstResult(startIndex).setMaxResults @`L;_S+
#Pg`0xiV
(pageSize).list(); TS6xF?
PaginationSupport ps = DfAF-Yhut
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new PaginationSupport(items, totalCount, pageSize, "D.<~!
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startIndex); ]Wkgpfd56
return ps; RQ8d1US
} Nq`;\E.M
}, true); qG;tD>jy
} ZcXAqep8'
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public List findAllByCriteria(final r
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DetachedCriteria detachedCriteria){ u:p OP
return(List) getHibernateTemplate Bu=1-8@=qs
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().execute(new HibernateCallback(){ ]?=87w
publicObject doInHibernate n5d8^c! 2
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(Session session)throws HibernateException { <K^a2 D
Criteria criteria = PSq?8.
8S8qj"s
detachedCriteria.getExecutableCriteria(session); I9qZE=i
return criteria.list(); o:QL%J{[
} sr;&/l#7h
}, true); pL{oVk#,
} aNu.4c/5
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public int getCountByCriteria(final ?.`
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DetachedCriteria detachedCriteria){ M5WB.L[@q
Integer count = (Integer) 2@tnOs(*
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getHibernateTemplate().execute(new HibernateCallback(){ aU(.LC
publicObject doInHibernate o C|oh
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(Session session)throws HibernateException { l-%] f]>
Criteria criteria = Fqw4XR_`~
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detachedCriteria.getExecutableCriteria(session); VVSt,/SO
return 5/n L[4Z
.*`^dt
criteria.setProjection(Projections.rowCount m)L50ot:/
bss2<mqlH
()).uniqueResult(); C,+
} J*rYw5QB
}, true); /HRKw
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return count.intValue(); `]W9Fj<1j
} eAW)|=2
} v)O0i2
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b, a7XANsh
用户在web层构造查询条件detachedCriteria,和可选的 ftRFG
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 GU>j8.
8D)1ZUx7`
PaginationSupport的实例ps。 e;XRH<LhAU
gf>H-718F
ps.getItems()得到已分页好的结果集 iHNQxLkk{:
ps.getIndexes()得到分页索引的数组 0M;g&&mF
ps.getTotalCount()得到总结果数 eQuw uT
ps.getStartIndex()当前分页索引 q<3La(^/
ps.getNextIndex()下一页索引 K*5gb^Ul
ps.getPreviousIndex()上一页索引 -crMO57/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错
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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 m^XO77"
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一下代码重构了。 Kkq-x'gt^
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我把原本我的做法也提供出来供大家讨论吧: ykbfK$jz
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首先,为了实现分页查询,我封装了一个Page类: JfkEJk<
java代码: ggPGKY-b=
VB90 5%
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/*Created on 2005-4-14*/ <xeB9
package org.flyware.util.page; @,oc%m
fUf1G{4
/** F_:Wu,dUZ
* @author Joa pmBN?<
* EoutB Vm
*/ =_=%1rI~
publicclass Page { awR !=\
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/** imply if the page has previous page */ 8!35
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privateboolean hasPrePage; JZ`u?ZaJ/s
c[2ikI,n[
/** imply if the page has next page */ ??e|ec2%
privateboolean hasNextPage; k(Xs&f
`
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/** the number of every page */ G?v<-=I
privateint everyPage; .B xQF
*2/qm:gB
/** the total page number */ (t3gNin
privateint totalPage; &V
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i?d545. u
/** the number of current page */ :4[>]&:u3
privateint currentPage; ~Qif-|[V
"Ia.$,k9
/** the begin index of the records by the current {Pe&J2
+
- s'W^(
query */ ;\}dQsX
privateint beginIndex; (D[~Z!
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b
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/** The default constructor */ :I"22EH
public Page(){ =/j!S|P
OH`zeI,[*
} .!^OmT,u
1F>8#+B/W
/** construct the page by everyPage >q?{'#i
/
* @param everyPage sa<\nH$_X
* */ 7Oe$Ou
public Page(int everyPage){ 5h Sd,#:
this.everyPage = everyPage; 8(-
29
} &b,A-1`w_
dpchZ{
/** The whole constructor */ X!6dg.n5
public Page(boolean hasPrePage, boolean hasNextPage, z|],s]F>G
cV1E<CM
5`&@3
m9/
int everyPage, int totalPage, c1i[1x%
int currentPage, int beginIndex){ '`gnJX
JO
this.hasPrePage = hasPrePage; uj\&-9gEi
this.hasNextPage = hasNextPage; V/DMkO#a
this.everyPage = everyPage; cGo_qR/B(>
this.totalPage = totalPage; r/':^Ex
this.currentPage = currentPage; 9MJ:]F5+
this.beginIndex = beginIndex; ^^
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} 6)=;cc{Vr
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/** Q~Nq5[
* @return 5cM%PYU4:v
* Returns the beginIndex. dtV*CX.D.7
*/ H/ e jO_{
publicint getBeginIndex(){ /W
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return beginIndex; -/B*\X[
} !]7b31$M_
N0$
uB"
/** OU/3U(%n]e
* @param beginIndex Fsq)co
* The beginIndex to set. HnFH|H<Uf
*/ "g"%7jK
publicvoid setBeginIndex(int beginIndex){ $z)egh(z
this.beginIndex = beginIndex; h(~of(
} Je"XIhBr
IcqzMmb
/** |FaK=e
* @return "5$p=|
* Returns the currentPage. 3 %r*~#nz
*/ ? YIe<
publicint getCurrentPage(){ *yZta:(w-W
return currentPage; h<'tQGC
} 3AP=
#@V<{/;49
/** mo4F\$2N
* @param currentPage cw0@Z0
* The currentPage to set. ^I6Vz?0Jl
*/ (?7}\B\
publicvoid setCurrentPage(int currentPage){ m4~~ q[t
this.currentPage = currentPage; c":2<:D&
} N`X|z
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/** v3n
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* @return y'oH>l+n
* Returns the everyPage. 0&kmP '
*/
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publicint getEveryPage(){ cj2^wmkB
return everyPage; 2}.~
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} w!d(NA<|0]
h<CRW-
/** g38MF
* @param everyPage s nNd7v.U6
* The everyPage to set. 5YI6$ZdQ
*/ c&<Ei1
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; RA+M.
} #c/K.?
@L607[!?
/** )#? K2E
* @return u?z,Vs"
* Returns the hasNextPage. ]}&HvrOld
*/ Nd;pkssd
publicboolean getHasNextPage(){ AS4oz:B
return hasNextPage; zqXDD; w3
} |1(L~g
GJ?J6@|
/** MQ'=qR
* @param hasNextPage N
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* The hasNextPage to set. ]h`d>#Hw!
*/ fCO<-L9k$
publicvoid setHasNextPage(boolean hasNextPage){ (II#9n)
this.hasNextPage = hasNextPage; 79jnYjk
} QPFv]^s(
:8v? 6Q
/** @y
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* @return O2lM;="
* Returns the hasPrePage. T$DFTr\\
*/ i8*(J-M
publicboolean getHasPrePage(){ Oo~
return hasPrePage; ?2gXF0+~Y2
} SHnMqaq
X7?14W
/** wr>6Go%
* @param hasPrePage gla'urb[i|
* The hasPrePage to set. -<u_fv
*/ &pv*TL8
publicvoid setHasPrePage(boolean hasPrePage){ .\
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this.hasPrePage = hasPrePage; (
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} XHJ/211
TTo?BVBK
/** *~UK5Brf1
* @return Returns the totalPage. I;{Ua*
* $9G".T
*/ }Os7[4RW
publicint getTotalPage(){ M pz9}[`3g
return totalPage; W$z^U)|t
} XWB#7;,R
zRR^v&.9K
/** Gy'/)}}Z
* @param totalPage lI9|"^n7F
* The totalPage to set. MTbCL53!-
*/ Izfq`zS+\s
publicvoid setTotalPage(int totalPage){ 7G Jhc
this.totalPage = totalPage; cNy*< Tv
} c48I-{?
1_@vxi~aW_
} M'NOM>8
P (fWJVF7
AFsYP/g]
N=@8~{V.
}C
JK9*Z
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 7?uIl9Vk>(
SU. $bsu
个PageUtil,负责对Page对象进行构造: FlbM(ofY
java代码: ji5Nq+S2
q9Lq+4\
1<0Z@D~F
/*Created on 2005-4-14*/ B\~(:(OPM]
package org.flyware.util.page; [E qZj/
:;&3"-
import org.apache.commons.logging.Log; {@ tO9pc`8
import org.apache.commons.logging.LogFactory; K[q-[q#yc
#V@vz#bo=
/** ~#=70
* @author Joa (w%9?y4Q
* T7(U6yN
*/ A%EGu4
publicclass PageUtil { ^W0eRT
ERfSJ
privatestaticfinal Log logger = LogFactory.getLog )jw!,"_4
-]:1zU
(PageUtil.class); 80LN(0?x
Z:VT%-
/** 2=n,{rkmj%
* Use the origin page to create a new page uA\KbA.c;U
* @param page M1K[6V!
* @param totalRecords ii ^Nxnc=
* @return LiJ. /
*/ 'D^@e0.3
publicstatic Page createPage(Page page, int yDi'@Z9R?
N1dM,H
totalRecords){ d.y-R#F_]
return createPage(page.getEveryPage(), @:P:`Zk
9#\oGzDN
page.getCurrentPage(), totalRecords); t<SCrLbz
} w2V:g$~,
Htce<H-P
/** 0w6"p>s>c
* the basic page utils not including exception YF)c.Q0
`Oe}OSxnT
handler
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* @param everyPage BHS8MV L@
* @param currentPage zCj#Nfm
* @param totalRecords -8sB\E
* @return page KtaoU2s
*/ Ots] y
publicstatic Page createPage(int everyPage, int ohPDknHp
E~`<n]{G-C
currentPage, int totalRecords){ Y-]Ne"+vf
everyPage = getEveryPage(everyPage); %WFZ&>en&
currentPage = getCurrentPage(currentPage); K^c%$n:}+
int beginIndex = getBeginIndex(everyPage, P5Pb2|\*
Mu$"fYKf"
currentPage);
9-Xr
int totalPage = getTotalPage(everyPage, `q7X(x
H) q_9<;
totalRecords); 3:3>k8
boolean hasNextPage = hasNextPage(currentPage, ;<BMgO}N
OJ<V<=MYZ
totalPage); Uq(fk9`6
boolean hasPrePage = hasPrePage(currentPage); LbnW(wr6:(
9@ :QBe3]
returnnew Page(hasPrePage, hasNextPage, gO_d!x*
everyPage, totalPage, <!PbD
currentPage, *NoixV1>
P u,JR
beginIndex); %kV #UzL
} 8g3?@i
=dY!-#yg!
privatestaticint getEveryPage(int everyPage){ q'`LwAU}
return everyPage == 0 ? 10 : everyPage; Z<[:v2
} ?GeMD
/]
otdm rw|
privatestaticint getCurrentPage(int currentPage){ &LHS<Nv^:
return currentPage == 0 ? 1 : currentPage; ed$w5dv
} 6rN.)dL.#N
dg@'5.ApPu
privatestaticint getBeginIndex(int everyPage, int 9QEK|x`8
$)VnHr `hy
currentPage){ !OMl-:KUzE
return(currentPage - 1) * everyPage; 8l
>Xbz
} Tvd: P^C
T<o8lL
privatestaticint getTotalPage(int everyPage, int &Yd6w}8
";
mlQyP
totalRecords){ \ 9#X]H
int totalPage = 0; F_nXsKem
`':G92}#
if(totalRecords % everyPage == 0) M,oRi;V
totalPage = totalRecords / everyPage; k;l^y%tzp
else &L r~x#Wx
totalPage = totalRecords / everyPage + 1 ; 8_T9[]7V8
axz.[L_elB
return totalPage; q;QE(}.g
} fY!9i5@'
kp^q}iS
privatestaticboolean hasPrePage(int currentPage){ ev1:0P
return currentPage == 1 ? false : true; G@scz!Nt
}
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aA'of>'ib|
privatestaticboolean hasNextPage(int currentPage, wx_j)Wij6
mi@ni+2Tn
int totalPage){ -{NP3zy
return currentPage == totalPage || totalPage == u0nIr9
Dfy=$:Q
0 ? false : true; 1Hs'YzvY
} gPIl:, d(
zEi\#Zg$
Hh*
KcIRX
} Y-~MkB
3|bbJ6*.<
S%jFH4#
j8;Uny9
D_ XOYzN}
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。 {2U3
C~T*Wlk
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 3;3 cTXR?=
5.
+_'bF|
做法如下: H/ar:j
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 C@u}tH
)
t\f[->f
的信息,和一个结果集List: me$nP}%C&
java代码: '~zi~Q7M
z-h?Q4;
,@\z{}~v
/*Created on 2005-6-13*/ 1,+swFSN
package com.adt.bo; F12$BKDH
.z^O y_S{
import java.util.List; <TgVU.*
Ru4M7%
import org.flyware.util.page.Page; /q)
H0b
sW76RKX8
/** Ezr q2/~Q
* @author Joa ?%$~Bb _
*/ 3!`_Q%
publicclass Result { :KS"&h{ SY
dnkHx
private Page page; JA4}Bwn
LQV&;O4'
private List content; ?RS4oJz,5g
gyxC)br
/** K$O2
Fq@y
* The default constructor $@84nR{>
*/ ll*Ez"
public Result(){ ;7*T6~tv
super(); 2 a*+mw
} /#zs
03"FK"2S
/** V!NRBXg
* The constructor using fields k]~$AaNq
* p-H}NQ\
* @param page LIT`~D
* @param content =MwR)CI#
*/ s"p\-Z
public Result(Page page, List content){ c )=a;_h
this.page = page; syCT)}T6z
this.content = content; PbFbihg
} IkO[R1K
a)I>Ns)
/** }zqo<o
* @return Returns the content. i*@ZIw
*/ 59i2*<k
publicList getContent(){ 8C@6
b4VK
return content; Q\N >W+d
} x+b.9f4xJ
&P"1 3]^@
/** 1DGl[k/zv
* @return Returns the page. f?>
?jf
*/ m#4h5_N
public Page getPage(){ ./^8L(
return page; .&I!2F
} ^m
AxV7k
5rmQ:8_5
/** EAy@kzY?
* @param content )0g!lCfb
* The content to set. <p-@XzyE
*/ 'H#0-V"=
public void setContent(List content){ \S&OAe/b
this.content = content; /U-+ClZi@
} 9e.$x%7j
ddd2w
/** Y#6LNI
* @param page 2p4iir
* The page to set. lJ,\^\q
*/ U@D\+T0
publicvoid setPage(Page page){ f1sp6S0V\
this.page = page; wQ[!~>A
} g_Rp}6g
} | g1Cs
p.b#RY
%~kE,^
Onou:kmf1
4wGBB{X
2. 编写业务逻辑接口,并实现它(UserManager, y&bZai8WlE
gZBKe!@a|
UserManagerImpl) L\5:od[EP
java代码: )rlkQ'DN
ii>^]iT
?%#no{9
/*Created on 2005-7-15*/ dBS_N/
package com.adt.service; 2.]d~\
\RRSrPLd-
import net.sf.hibernate.HibernateException; Qwve-[
}RKsS3}
import org.flyware.util.page.Page; D,|TQQ
=e0MEV#s.
import com.adt.bo.Result; m AET`B "
j}`ku9S~
/** wy{sS}
* @author Joa ZS=;)
*/ Qr7|;l3
publicinterface UserManager {
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~)[pL(4
public Result listUser(Page page)throws [>\e@ =
Bj9FSKiH
HibernateException; 9I$}=&"
y?A*$6
} EyA(W;r.
`T{CB) ?9
9_.pLLx
,?IXfJ`c
{P\Ob0)q
java代码: q/Ji}NGm
}_}
~66v.`K!
/*Created on 2005-7-15*/ GoH.0eQ^
package com.adt.service.impl;
qFLt/
>
>{-rl@^H:
import java.util.List; <eP,/H
qs= i+
import net.sf.hibernate.HibernateException; 9}Za_ZgG
-dN`Ok<g
import org.flyware.util.page.Page; ,\#j6R,{I
import org.flyware.util.page.PageUtil; W$&*i1<a+
L<XX?I\p
import com.adt.bo.Result; i,%N#
import com.adt.dao.UserDAO; Io>U-Zd\>
import com.adt.exception.ObjectNotFoundException; Pth4_]US
import com.adt.service.UserManager; G`&P|xYg
AE`UnlUSF
/** Ov4 [gHy&
* @author Joa HZS.%+2
*/ ~m0=YAlk?
publicclass UserManagerImpl implements UserManager { =CS$c?
CdcBE.%<
private UserDAO userDAO; w)1SZ}
k6Vs#K7a
/** ;~WoJlEK3
* @param userDAO The userDAO to set. -*Qg^1]i+
*/ GukwN]*OY
publicvoid setUserDAO(UserDAO userDAO){ 3m2y<l<
this.userDAO = userDAO; M9Yov4k,4]
} 2chT^3e
QwF.c28[
/* (non-Javadoc) 4`cf FowK~
* @see com.adt.service.UserManager#listUser M195[]
SrOv*
D 3
(org.flyware.util.page.Page) ;- Vs|X
*/ d(9Sk Xr
public Result listUser(Page page)throws /k^j'MMQs6
rq1~%S
HibernateException, ObjectNotFoundException { +|K,\
{'U
int totalRecords = userDAO.getUserCount(); 5GPAt
if(totalRecords == 0) 5H 1x-b
throw new ObjectNotFoundException P9Eh,j0_
kI5LG6
("userNotExist"); |8x_Av0
page = PageUtil.createPage(page, totalRecords);
2)n%rvCQ
List users = userDAO.getUserByPage(page); 2(e;pM2Dq
returnnew Result(page, users); VeQ [A?pER
} (4`Tf*5hHa
L ]BTX]
} S_VzmCi
KK-+vq
ZX{eggXl
w>Ft5"z
zx"0^r}
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 SL^%Zh/~
to#2.
询,接下来编写UserDAO的代码: cmaha%3d
3. UserDAO 和 UserDAOImpl: &qa16bz
java代码: wjOqCF"
v{\~>1J{
?q5HAIZ`
/*Created on 2005-7-15*/ "[Tr"nI
package com.adt.dao; fKua om9
Q-U,1b
import java.util.List; D6e<1W
e+@.n
import org.flyware.util.page.Page; +ZBj_Vw*|
:X*uE^bH
import net.sf.hibernate.HibernateException; qrt2uE{K
!yV)EJ:$
/** )%!X,
* @author Joa )MX%DQw
*/ J=n^&y
publicinterface UserDAO extends BaseDAO { pcm1IwR`
-OfAl~ 4
publicList getUserByName(String name)throws ]7h;MR
^AUQsRA7PZ
HibernateException; lPl JL`e
2b:I.
publicint getUserCount()throws HibernateException; )IE)a[wo
V<REcII.
publicList getUserByPage(Page page)throws m :]F&s
D[Ld=e8t
HibernateException; fK=vLcH
8}^ym^H|j
} &0-Pl.M
ayA_[{j%X
9AQ2FD
mOYXd,xd
m(WVxVB
java代码: k_%maJkXp
q?&J