Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 sm_:M| [D
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 l w%fY{
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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 y.O? c&!
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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 i44:VR|
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分页支持类: ,7QnZ=F
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java代码: v,M2|x\r}
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package com.javaeye.common.util; ;m5M:Z"
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import java.util.List; WEsH@
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publicclass PaginationSupport { lp9<j1Wl
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publicfinalstaticint PAGESIZE = 30; 9V"j=1B}
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privateint pageSize = PAGESIZE; )T4L^^`
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privateList items; Qb|dp~K.M
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privateint totalCount; )R|7> 97
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privateint[] indexes = newint[0]; [%@zH
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privateint startIndex = 0; H 0h
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public PaginationSupport(List items, int {10ms_s
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totalCount){
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setPageSize(PAGESIZE); H,I}R
setTotalCount(totalCount); :D,YR(])
setItems(items); ew"Fr1UGYZ
setStartIndex(0); 7&QVw(:)M
} u qyf3bK
ryT8*}o
public PaginationSupport(List items, int n (|>7
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totalCount, int startIndex){ x'KsQlI/
setPageSize(PAGESIZE); OP&[5X+Y
setTotalCount(totalCount); D!P?sq _5r
setItems(items); XMdc n,
setStartIndex(startIndex); wiGwN
} ]lo1Kw
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public PaginationSupport(List items, int KF'M4P
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totalCount, int pageSize, int startIndex){ |HEw~x<=
setPageSize(pageSize); 3(&.[o
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setTotalCount(totalCount); Z-<u?f8{*
setItems(items); #.><A8J
setStartIndex(startIndex); $"i690
} \fhT#/0N
@Dy.HQ~
publicList getItems(){ '-vyQ^
return items; yRznP)
} y(dS1.5F
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publicvoid setItems(List items){ 42u\Y_^ID
this.items = items; zfZDtKq
} 8F*
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publicint getPageSize(){ `[KhG)Y7t
return pageSize; #SYWAcTkO}
} AH`15k_i
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publicvoid setPageSize(int pageSize){ ["F,|e{y$
this.pageSize = pageSize; eTc`FXw`
} .ndQ(B
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publicint getTotalCount(){ 8x"d/D
return totalCount; k)s 7Ev*
} ~D5MAEazS
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publicvoid setTotalCount(int totalCount){ ?a%i|Z7!
if(totalCount > 0){ 4I*Mc%dD
this.totalCount = totalCount; Q.1ohj0)
int count = totalCount / zl\#n:|
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pageSize; sJoi fl
7
if(totalCount % pageSize > 0) 0vp I#q
count++; F4Uk+|]Bu
indexes = newint[count]; 3\+p1f4
for(int i = 0; i < count; i++){ ~N9-an
indexes = pageSize * ,*[LnR
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i; }L!`K"^O&
} ^rwSbM$
}else{ ~-`02
this.totalCount = 0; Bs?F*,zDJ
} |esjhf}H>v
} fO^6q1a
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publicint[] getIndexes(){ 8~E)gV+v
return indexes; ;#9|l=
} MPbPq3an
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publicvoid setIndexes(int[] indexes){ r6JkoPMh
this.indexes = indexes; 8>q%1]X
} P@YL.'KU)
+
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publicint getStartIndex(){ fZ}Y(TG/
return startIndex; %>2t=)T
} ?MM3LA! <
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publicvoid setStartIndex(int startIndex){ AnY)T8w
if(totalCount <= 0) /zf>>O`
this.startIndex = 0; TEyx((SK
elseif(startIndex >= totalCount) }G+A_HF ^
this.startIndex = indexes 5Kj4!Ai
,,@`l\Pgd
[indexes.length - 1]; ATM:As:<@
elseif(startIndex < 0) ^~qs-.?
this.startIndex = 0; +[/47uFbI
else{ Lc<xgN+cJ
this.startIndex = indexes /dt!J
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[startIndex / pageSize]; |ozoc"'
} b',bi.FH
} b0Ov+ )7#
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publicint getNextIndex(){ rJZs
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int nextIndex = getStartIndex() + ZT8Ji?_n
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pageSize; %8CT -mQ
if(nextIndex >= totalCount) \t# 9zn>
return getStartIndex(); yM:~{;HLF
else h#>L:Wf5E
return nextIndex; i i@1!o
} 5`'=Ko,N
xeM':hD.o
publicint getPreviousIndex(){ IXvz&4VD
int previousIndex = getStartIndex() - |4.o$*0Y
gkML .u
pageSize; ](>7h_2B
if(previousIndex < 0) )]>G,.9C}
return0; QYfAf3te
else ~}-p5 q2
return previousIndex; uuYH6bw*d
} c48J!,jCd'
%;(|KrUN
} OI_/7@L
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抽象业务类 Of7) A
java代码: I49l2>
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/** ]9&q'7*L
* Created on 2005-7-12 `3y!XET
*/ _8b]o~[Z+
package com.javaeye.common.business; {IPn\Bka
;q,)NAr&
import java.io.Serializable; `x$}~rP&)!
import java.util.List; 'CX.qxF1;p
;5Vk01R
import org.hibernate.Criteria; +yb$[E*
import org.hibernate.HibernateException; f'6qJk%J
import org.hibernate.Session; Uk*;C
import org.hibernate.criterion.DetachedCriteria; R^yZG{?t
import org.hibernate.criterion.Projections; _d[2_b1
import 6+$d
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org.springframework.orm.hibernate3.HibernateCallback; 40Qzo%eL
import OKZam ik~
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org.springframework.orm.hibernate3.support.HibernateDaoS HM@}!6/s
7t-*L}~WA
upport; foz5D9sQ
B}q
import com.javaeye.common.util.PaginationSupport; ?$J7%I@
AZy~Q9Kc
public abstract class AbstractManager extends -':"6\W
noaN@K[GO
HibernateDaoSupport { Xh0wWU*
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privateboolean cacheQueries = false; Lk`k>Nn)
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privateString queryCacheRegion; qXB03}] G
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publicvoid setCacheQueries(boolean *]m kyAhi
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cacheQueries){ (Gi+7GMV'
this.cacheQueries = cacheQueries; g\qL}:
} zY+t ,2z
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publicvoid setQueryCacheRegion(String sm2p$3v
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queryCacheRegion){ D]pK=247
this.queryCacheRegion = 7"n)/;la
6)#- 5m
queryCacheRegion; tB ,.
} T Oco({/_/
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publicvoid save(finalObject entity){ Qh|-a@
getHibernateTemplate().save(entity); yZ;k@t_WRD
} `rz`3:ZH
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publicvoid persist(finalObject entity){ xH"W}-#[
getHibernateTemplate().save(entity); ?GUz?'d
} Ez/\bE
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publicvoid update(finalObject entity){ S2'`|uI
getHibernateTemplate().update(entity); 6+Wr6'kuH
} .*EOVo9S
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publicvoid delete(finalObject entity){ ^A *]&%(h
getHibernateTemplate().delete(entity); (:.Q\!aZ1
} 23}BW_m
}\`(m\2xo
publicObject load(finalClass entity, POqRHuFq
u=@h`5-fp
finalSerializable id){ j8[`~pb
return getHibernateTemplate().load 'R4>CZ%jV
1Lm].tq
(entity, id); I~p8#<4#b
} 9n>$}UI\
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publicObject get(finalClass entity, >/TB_ykb
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finalSerializable id){ =2RhPD
return getHibernateTemplate().get f?=r3/AO
1z})mfsh
(entity, id); -+3be(u
} O+G~Qp0b>
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publicList findAll(finalClass entity){ 93Mdp9v+i
return getHibernateTemplate().find("from ^%n124
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" + entity.getName()); !lQ#sL`
} F5N>Uqr*oN
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publicList findByNamedQuery(finalString 2Vz'n@g=
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namedQuery){ :DZLjC
return getHibernateTemplate ,}9f(`
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mnI
().findByNamedQuery(namedQuery); [;(]Jy
} tA`mD >[
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publicList findByNamedQuery(finalString query, P]pmt1a
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finalObject parameter){ tWpl`HH
return getHibernateTemplate KI Ek/]<H
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().findByNamedQuery(query, parameter); ? .c?Pu
} 8ivRp<9
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publicList findByNamedQuery(finalString query, |7rR99
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finalObject[] parameters){ 9 '2=
return getHibernateTemplate r_4TtP&UW
wl7 M fyU
().findByNamedQuery(query, parameters); !2GHJHxv]c
} xK$}QZ)
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publicList find(finalString query){
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return getHibernateTemplate().find q{a#HnZo"
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(query); Z:I*y7V-
} 0Vf)Rw1%I
B }6Kd
publicList find(finalString query, finalObject R<Z^L~)
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parameter){ .D+RLO z
return getHibernateTemplate().find /VRUz++K
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(query, parameter); .|T2\M
} *Y8XP8u/
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public PaginationSupport findPageByCriteria 0;}Aj8Fle
j._G7z/LJ
(final DetachedCriteria detachedCriteria){ ;5<P|:^
return findPageByCriteria 0r1g$mKb
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); f.@Xjf
} BRe{1i 6
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public PaginationSupport findPageByCriteria >OT\~C
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(final DetachedCriteria detachedCriteria, finalint 5!<o-{J[(=
dY1J<L}")
startIndex){ aIQOs
return findPageByCriteria ;U
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(detachedCriteria, PaginationSupport.PAGESIZE, /4yOs@#
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startIndex); W3^.5I
} |,3l`o
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public PaginationSupport findPageByCriteria Hfke
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(final DetachedCriteria detachedCriteria, finalint moCK-:
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pageSize, pqJ)G;%9
finalint startIndex){ d5Qd'
return(PaginationSupport) ` "B^{o
Y =9j2 ]t
getHibernateTemplate().execute(new HibernateCallback(){ CQ<8P86gt
publicObject doInHibernate ai4PM
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(Session session)throws HibernateException { VQ2Fnb4
Criteria criteria = l1}R2lSEO
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detachedCriteria.getExecutableCriteria(session); QeL{Wa-2F
int totalCount = yOc|*O=]U
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((Integer) criteria.setProjection(Projections.rowCount J2'K?|,m
QskUdzQ=
()).uniqueResult()).intValue(); i (0hvV>'
criteria.setProjection BH5w@
prUHjS
(null); '| &,E#`
List items = 8hZwQ[hr
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criteria.setFirstResult(startIndex).setMaxResults PT+c&5A S
<^Nk.E
(pageSize).list(); x:qr \Rz
PaginationSupport ps = H-Pq!9[DB
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new PaginationSupport(items, totalCount, pageSize, 2% %|fU9
l]$40 j
startIndex); u%xDsTDP
return ps; U%q:^S%#eG
} qL3@PSN?|
}, true); Wk}D]o0^@
} O] H=s
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public List findAllByCriteria(final p'80d:
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DetachedCriteria detachedCriteria){ EMhr6</
return(List) getHibernateTemplate TMww
{ UOhVJy
().execute(new HibernateCallback(){ l~['[Ub0)
publicObject doInHibernate YN^T$,*
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(Session session)throws HibernateException { R4SxFp
Criteria criteria = kxh 5}eB
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detachedCriteria.getExecutableCriteria(session); /1[gn8V691
return criteria.list(); g?V&mu
} Y9tV%
}, true); XCm\z9F
} k-Fdj5/
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public int getCountByCriteria(final "<x&pQZ%
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DetachedCriteria detachedCriteria){ $3 4j6;oN
Integer count = (Integer) UWw}!1
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getHibernateTemplate().execute(new HibernateCallback(){ >t0%?wj)Y
publicObject doInHibernate @zrNN>
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(Session session)throws HibernateException { a.DX%C/5
Criteria criteria = 69/?7r
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detachedCriteria.getExecutableCriteria(session); t:=k)B
return H_Os4}
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criteria.setProjection(Projections.rowCount $/paEn"
xs%LRF#u
()).uniqueResult(); U` hfvTi
} 8R}K?+]
}, true); +]c}rWm
return count.intValue(); bDWeU}
} f05=Mc&)
} /$:U$JVb?l
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用户在web层构造查询条件detachedCriteria,和可选的 ~{M@?8wi
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 qo_]ZKL44
Sl>>SP
PaginationSupport的实例ps。 DjwQ`MA
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ps.getItems()得到已分页好的结果集 9cfR)*Q
ps.getIndexes()得到分页索引的数组 [@3SfQ
ps.getTotalCount()得到总结果数 "OL~ul5
ps.getStartIndex()当前分页索引 }lP 5GT2
ps.getNextIndex()下一页索引 /C$
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ps.getPreviousIndex()上一页索引 `?9T~,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 nU/;2=f<
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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 `G?qY8
n+;vjVS%
一下代码重构了。 3wC
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M&y5AB0
我把原本我的做法也提供出来供大家讨论吧: 2*u.3,aW
hD
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首先,为了实现分页查询,我封装了一个Page类: [M:S`{SbY
java代码: :c7CiP
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/*Created on 2005-4-14*/ !;dSC<
package org.flyware.util.page; FP@qh
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/** ^u)rB<#BR
* @author Joa i2PZ'.sL
* 8Kk\*8 <
*/ OCnFEX"
publicclass Page { 0E6lmz`O
kH?#B%N5
/** imply if the page has previous page */ 9?EVQ
privateboolean hasPrePage; 7>n"}8i
J :S'uxM
/** imply if the page has next page */ \.<KA
privateboolean hasNextPage; PAZ$_eSK6
| ^GyH$.
/** the number of every page */ XP?*=Z]
privateint everyPage; </s,pe79B
v <Hb-~
/** the total page number */ z[9UQU~x?
privateint totalPage; 6E|S
*)> do
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/** the number of current page */ o| D^`Z
privateint currentPage; <I2z&
2dbRE:v5
/** the begin index of the records by the current 4D"4zp7
6)[<)?A.[
query */ #3MKH8k&~
privateint beginIndex; {TAw)!R~
^od<JD4
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/** The default constructor */ q`Q}yE>9
public Page(){ Y~qb;N\
\VN=Ef\E
} k^An97J
Q2s&L]L=
/** construct the page by everyPage ctI{^f:
* @param everyPage u Z(? >
* */ u~F~cDu
public Page(int everyPage){ w%xCTeK[
this.everyPage = everyPage; s-?fUqA
} m22wF>9
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/** The whole constructor */ !wh&>3~
public Page(boolean hasPrePage, boolean hasNextPage, 'fY9a(Xt.
HI!4
({[,$dEa;
int everyPage, int totalPage, #I%s3
int currentPage, int beginIndex){ WY>Knp=
this.hasPrePage = hasPrePage; M"wue*&
this.hasNextPage = hasNextPage; T~ k)uQ
this.everyPage = everyPage; !LIlt`ag9
this.totalPage = totalPage; /1fwl5\
this.currentPage = currentPage; ^M[P-#X_
this.beginIndex = beginIndex; &88oB6$D^q
} ?+`xe{k
Q"VMNvKYB
/** :"'nK6>
* @return DWf$X1M
* Returns the beginIndex. ai^|N.!
*/ ~<ri97)
publicint getBeginIndex(){ g}Qx`65:
return beginIndex; l\Xd.H" j,
} ycX{NDGs
ngyY
/** %l$W*.j|;
* @param beginIndex 91d },Mq:
* The beginIndex to set. 6 bO;&
*/ :6Pad
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; ;p Z[|
} 3 QCVgo
i\
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/** MR;X&Up6!
* @return )Yj%#
* Returns the currentPage. EUcKN1
*/ MCYl{uH!
publicint getCurrentPage(){ +)/Uu3"=
return currentPage; |t6~%6^8
} PRr*]$\&Mj
:.&{Z"
/** ZkWL_ H)
* @param currentPage IZNOWX|Z;
* The currentPage to set. <avQR9'&
*/ WS,7dz
publicvoid setCurrentPage(int currentPage){ &<1`O
this.currentPage = currentPage; X")|Uw8Kl/
} }ugxN0
LmLGki$w
/** GYK\LHCPd
* @return M_1;$fWq
* Returns the everyPage. @Icq1zb]
y
*/ VLI'
publicint getEveryPage(){ CL9yEy"V
return everyPage; OJ3UE(,I=
} C`K^L=8`{
GozPvR^/
/** ctn,
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* @param everyPage ' [p)N,
* The everyPage to set. .C!vr@@]
*/ s3
B'>RG}
publicvoid setEveryPage(int everyPage){ 3V;gW%>
this.everyPage = everyPage; .+.j*>q>u
} 8r:M*25
R7_VXvm>z
/** D>#l -{d
* @return S# we3
* Returns the hasNextPage. &Lj@9\Dh
*/ 5:_hP{ @
publicboolean getHasNextPage(){ 1r9 f[j~
return hasNextPage; -5Utlos
} |b.z*G
HW[L[&/
/** *e{PxaF!C
* @param hasNextPage LU2waq}VA
* The hasNextPage to set. p3]Q^KFS
*/ l-O$ m
publicvoid setHasNextPage(boolean hasNextPage){ 5<R%H{3j
this.hasNextPage = hasNextPage; 1W,(\'^R
} xeA#u
J
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/** C/tr$.2H=
* @return WUoOGbA `
* Returns the hasPrePage. &M[f&_"8Q
*/ WES#ZYtT
publicboolean getHasPrePage(){ =r4!V>
return hasPrePage; q,l)I+
} Uems\I0
sqO<J$tz
/** 7"2b H
* @param hasPrePage ?M}S|dsmE
* The hasPrePage to set. p
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*/ qx)?buAij
publicvoid setHasPrePage(boolean hasPrePage){ _8fA?q=
this.hasPrePage = hasPrePage; JK)qZ=
} b{cU<;G)y.
0b-?q&*_
/** p]&j;H.
* @return Returns the totalPage. ;hDa@3|]34
* wEEn?
*/ WFv!Pbq,
publicint getTotalPage(){ ,.mBJSE3
return totalPage; }iiHr|l3
} S2^>6/[xM
{qpi?oY
/** ZxHJ<2oD
* @param totalPage w#y2_
* The totalPage to set. (Tvcq
*/ $dg9z}D
publicvoid setTotalPage(int totalPage){ eph)=F$
this.totalPage = totalPage; FfFak@H
} veh
5}2
}*wLEa
} {^ec(EsO#
l|"6yB |
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,T5u'";
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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 ?ny=
HZjf`eM,
个PageUtil,负责对Page对象进行构造: S\ ,mR4:
java代码: 4_=Ja2v8;`
nWYCh7
@F5f"8!.\
/*Created on 2005-4-14*/ x_<qzlQt
package org.flyware.util.page; jgu*Y{ocm
-"TR\/
import org.apache.commons.logging.Log; pV\YG B+
import org.apache.commons.logging.LogFactory; LBlN2)\@
6(V
/yn~
/** IApT'QNM
* @author Joa >,5i60Q
* [
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*/ u'5`[U
-!
publicclass PageUtil { 2Aq~D@,9=:
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privatestaticfinal Log logger = LogFactory.getLog h0 |}TV^UJ
6[ga$nF?
(PageUtil.class); 2W<n5o
<z)m%*lvU
/** g.DLfwI|
* Use the origin page to create a new page vfc[p ^
* @param page @w9{5D4
* @param totalRecords FQsUm?ac:
* @return t;q7t!sC]
*/ -*ELLY[
publicstatic Page createPage(Page page, int :}}%#/nd
iz^qR={bW
totalRecords){ IyUdZ,ba
return createPage(page.getEveryPage(), UE0$ o?
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W*m
page.getCurrentPage(), totalRecords); 7=}F{U
} 2.I^Xf2
@cvP0A
/** `}gbc69
* the basic page utils not including exception PX
O!t]*
>t+
qe/
handler ^>c8t_RG
* @param everyPage F`+\>ae$h
* @param currentPage S33j?+Vs
* @param totalRecords J ++v@4Z
* @return page )0 Z! n
*/ I*|P@0
publicstatic Page createPage(int everyPage, int Wr~yK? : ]
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currentPage, int totalRecords){ @R6 ttx
everyPage = getEveryPage(everyPage); ;iQEkn2T|}
currentPage = getCurrentPage(currentPage); mLbN/M
int beginIndex = getBeginIndex(everyPage, YlK7;yrq(
]7 GlO9
currentPage); #@.-B,]
int totalPage = getTotalPage(everyPage, !X^Ce)1K
qa'gM@]
totalRecords); PR7f(NC
boolean hasNextPage = hasNextPage(currentPage, >4i>C
]/2T\w.<
totalPage); @r7:NU}
boolean hasPrePage = hasPrePage(currentPage); l&(l$@t
3c'#6virz
returnnew Page(hasPrePage, hasNextPage, 8;gXg
everyPage, totalPage, 8F5|EpB9M
currentPage, 'xK.UI
Q(7ob}+jQ
beginIndex); @E9" Zv-$
} PO-"M)M
5p"BD'^:
privatestaticint getEveryPage(int everyPage){ Zk-~ar
return everyPage == 0 ? 10 : everyPage; hlJpElYf
} IzLF'F
#(;<-7M2
privatestaticint getCurrentPage(int currentPage){ LO%!Z,}
return currentPage == 0 ? 1 : currentPage; rfcN/:k
} "9y(
}
j f~wBmd7
privatestaticint getBeginIndex(int everyPage, int lTRl"`@S
jQs>`P-CM
currentPage){ (#\pQ51
return(currentPage - 1) * everyPage; TV59(bG.2
} s<QkDERMX
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privatestaticint getTotalPage(int everyPage, int a|j%n
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totalRecords){ fRZ KEIyk
int totalPage = 0; ^-)txC5{T
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if(totalRecords % everyPage == 0) 77 r(*.O|
totalPage = totalRecords / everyPage; \fWW'
else O'*@ Ytn
totalPage = totalRecords / everyPage + 1 ; afEF]i
1`bl&}6l|E
return totalPage; I s57F4[}
} IND ]j72
i&Fiq&V)[
privatestaticboolean hasPrePage(int currentPage){ 9]'&RyH=#
return currentPage == 1 ? false : true; {jKI^aC<[
} V\5 L?}
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privatestaticboolean hasNextPage(int currentPage, cW8\d
F'm(8/A$
int totalPage){ i{c@S:&@^
return currentPage == totalPage || totalPage == ;az5ZsvN
D
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0 ? false : true; 8P' ana
} e(
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} s,]%dG!
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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。
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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 tAu4haa4;
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做法如下: Ard]147
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 =}!Mf'
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的信息,和一个结果集List: [/M^[p
java代码: E6B!+s!]
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/*Created on 2005-6-13*/ XM1`x
package com.adt.bo; 0IkM
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import java.util.List; Z"-L[2E/{!
~V=<3X
import org.flyware.util.page.Page; q%>'4_
t(!r8!c
u}
/** K4Dp:2/K%
* @author Joa {svn=H
/
*/ Y/ot3[
publicclass Result { WG71k8af
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private Page page;
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private List content; G_H?f\/
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/** BQ</g* $;
* The default constructor D('2p8;2"7
*/ `?(Bt|<>
public Result(){ U5HKRO
super(); HmmS(fU
} g9fq5E<G
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/** <bck~E
* The constructor using fields &QX`NO6
* e?0q9W
* @param page zhI#f0c
* @param content
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*/ YV4#%I!<
public Result(Page page, List content){ (6p]ZY
this.page = page; #zUXyT#X
this.content = content; "[p@tc?5
} qZEoiNH(Tj
M6r^L6$N
/** <+#oBN
* @return Returns the content. kUx&pYv
*/ 3-Dt[0%{
publicList getContent(){ ppIbjt6r
return content; o\otgyoh
} 2L_6x<u'
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/** \vfBrN
* @return Returns the page. gwd (N
*/ nP~({:l8X
public Page getPage(){ `IpA.| Y
return page; IxR?'
} ma$Prd
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/** ^vs=f95
* @param content ^-CINt{O
* The content to set. f
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*/ )py{\r9X
public void setContent(List content){ }V;+l8
this.content = content; 3l<S}k@M)
} 22P$ ~ch
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/** sAJ7R(p
* @param page U_l'3oPJw
* The page to set. O#EV5FeF.
*/ lOwS&4UT
publicvoid setPage(Page page){ ,5Pl\keY
this.page = page; h0Z{,s}
} g$:Xuw1
} m4E)qCvy
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]{~NO{0@Y
[[~w0G~1
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2. 编写业务逻辑接口,并实现它(UserManager, `cQo0{xK
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UserManagerImpl) Do%-B1{ri
java代码: \o-&f:
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RC|!+TD
/*Created on 2005-7-15*/ IPSF]"}~
package com.adt.service; Wjh/M&,
f~OU*P>V@
import net.sf.hibernate.HibernateException; Xb
!MaNm)
P #F=c34u
import org.flyware.util.page.Page; vzel#
Xd E`d.
import com.adt.bo.Result; r,goRK.
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/** I2$T"K:eo
* @author Joa H2xeP%;$
*/ o`zr>
publicinterface UserManager { :!;'J/B@..
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public Result listUser(Page page)throws R:JX<Ba
Ll4bdz,
HibernateException; C'=k<-
{y] mk?j
} +bK.NcS
^ 5VK>
GhY1k";
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,
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java代码: /:6Wzj
1QZ&Mj^^
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/*Created on 2005-7-15*/ CSbI8 5F
package com.adt.service.impl; iz(u=/*\
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import java.util.List; N!Qg; (
WD;Y~|
import net.sf.hibernate.HibernateException; b5IA"w
=&0wr6
import org.flyware.util.page.Page; Bx"7%[
import org.flyware.util.page.PageUtil; t#nn@Yf
LNl#h
import com.adt.bo.Result; 3QSZ ZJ
import com.adt.dao.UserDAO; xt'tL:d
import com.adt.exception.ObjectNotFoundException; .,~(%#Wl$
import com.adt.service.UserManager; A`}yBSb
m|=Ecu
/** cw&Hgjj2
* @author Joa .*$OQA
*/ ;n=. {[,
publicclass UserManagerImpl implements UserManager { S.B<pjgt
4ww]9J
private UserDAO userDAO; )5%C3/Dl!
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/** k+V6,V)my
* @param userDAO The userDAO to set. FLoNE>q
*/ /!}'t
publicvoid setUserDAO(UserDAO userDAO){ >U1R.B7f
this.userDAO = userDAO; H* ,,^
} Hv]7e|
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/* (non-Javadoc) _8}QlT
* @see com.adt.service.UserManager#listUser s%iOUL2/
}
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(org.flyware.util.page.Page) '^%~JyU
*/ )CI1;
public Result listUser(Page page)throws ~9F ,%
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HibernateException, ObjectNotFoundException { Xd:7"/:r
int totalRecords = userDAO.getUserCount(); VN4yn| f/
if(totalRecords == 0) !@u>A_
throw new ObjectNotFoundException 30PZ{c&Rll
1tCQpf
("userNotExist"); H7+Xs%
page = PageUtil.createPage(page, totalRecords); E^_wI>
List users = userDAO.getUserByPage(page); {Z; jhR,
returnnew Result(page, users); x#~ x;)
} &X9Z
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} V&soN:HS
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ES <1tG
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 o01kYBD
>$gG/WD?KR
询,接下来编写UserDAO的代码: c4e_6=Iv
3. UserDAO 和 UserDAOImpl: -K(fh#<6KO
java代码: pqvOJ#?Q}=
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r
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/*Created on 2005-7-15*/ MyJ4><oG
package com.adt.dao; z|G9,:9
OQ :dJe6
import java.util.List; 0s#vwK13
!>x|7
import org.flyware.util.page.Page; lX:|iB
OE)~yKy
import net.sf.hibernate.HibernateException; ?EMK8;
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/** QQk{\PV
* @author Joa U(&oj e
*/ y#Ht{)C
publicinterface UserDAO extends BaseDAO { \&V0vN1
c~A4gtB=
publicList getUserByName(String name)throws "HD+rmUEH
sDqe(x}a
HibernateException; {qKxz9.y
eRbGZYrJ
publicint getUserCount()throws HibernateException; ^n#1<K[E
4vK8kkW1
publicList getUserByPage(Page page)throws GwsY-jf
HhA -[p
HibernateException; |VOg\[f
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} Mv|ykJoz"
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