Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 v1s0kdR,>
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 RMxFo\TK;
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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 ,fD#)_\g2
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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 -xU4s
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分页支持类: A]s|"Pav,
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java代码: !&vPG>V
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package com.javaeye.common.util; ]9NA3U7F
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import java.util.List; ?hnxc0~P
#qdfr3
publicclass PaginationSupport { xIa8Ac
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publicfinalstaticint PAGESIZE = 30; D1f}g
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privateint pageSize = PAGESIZE; tx||<8
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privateList items; ?=0BU}
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privateint totalCount; Hn!13+fS
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privateint[] indexes = newint[0]; #hF(`oX}4K
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privateint startIndex = 0; %*Lv
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public PaginationSupport(List items, int
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totalCount){ xy[aZr
setPageSize(PAGESIZE); {#4F}@Q
setTotalCount(totalCount); 3DS&-rN
setItems(items); BXB ZX@jVk
setStartIndex(0); :"I!$_E'
} cMp#_\B
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public PaginationSupport(List items, int %{;1i
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totalCount, int startIndex){ {>n\B~*,"C
setPageSize(PAGESIZE); z6;6 o!ej
setTotalCount(totalCount); B6xM#)
setItems(items); 5l4YYwd>v
setStartIndex(startIndex); , IDCbJ
} 6-J%Z%yT #
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public PaginationSupport(List items, int )4e?-?bK!
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totalCount, int pageSize, int startIndex){ *Sp_s_tS
setPageSize(pageSize); Gqs)E"h
setTotalCount(totalCount); +Fa!<txn
setItems(items); JK'FJ}Z4
setStartIndex(startIndex); Yh2[
nF_
} X)b@ia'"Wp
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publicList getItems(){ _T\cJcWf
return items; 5L\&"['
} HvzXAd
k{ ~0BK
publicvoid setItems(List items){ 2xK v;
this.items = items; p(Ux]_s%
} w?:tce
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publicint getPageSize(){ D1R$s*{
return pageSize; @L?KcGD
} mLm?yb:
I>JBGR`j
publicvoid setPageSize(int pageSize){ y~n1S~5cI
this.pageSize = pageSize; ohna1a^
} ACOn}yH
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publicint getTotalCount(){ o2~P
vef
return totalCount; 'e/wjV
} Z@,[a
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publicvoid setTotalCount(int totalCount){ S`8Iu[Ma
if(totalCount > 0){ Kv9Z.DY
this.totalCount = totalCount; .F},Z[a&
int count = totalCount / Kk`LuS?
T.}Y&,n$$5
pageSize; Kf1NMin7
if(totalCount % pageSize > 0) }`.d4mm
count++; gCq'#G\Z
indexes = newint[count]; #MFIsx)r
for(int i = 0; i < count; i++){ >#VNA^+t
indexes = pageSize * 10_#Z~aU
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i; =;Dj[<mJ45
} EpH_v`
}else{ niqknqW<t
this.totalCount = 0; N "}N>xe2
} 9l(T>B2a
} XY#.?<"Q8
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publicint[] getIndexes(){ &~=r .T
return indexes; .cm2L,1h
} ,Qs%bq{t
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publicvoid setIndexes(int[] indexes){ J$5Vjh'aM
this.indexes = indexes; k.z(.uc=
} 2+_a<5l~
@VPmr}p:{
publicint getStartIndex(){ 2RQ-L
return startIndex; PMUW<UI
} P ^ 4 @
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publicvoid setStartIndex(int startIndex){ |{v#'";O:
if(totalCount <= 0) ~Up{zRD"B
this.startIndex = 0; ?~b(iZ
elseif(startIndex >= totalCount) n*Uk<_WA
this.startIndex = indexes hJsP;y:@Lm
T7%!JBg@
[indexes.length - 1]; YZ`SF"Bd(
elseif(startIndex < 0) {
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this.startIndex = 0; K|YB)y
else{ BlQX$s]
this.startIndex = indexes +:"0%(
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[startIndex / pageSize]; $dF3@(p
} SiUu**zC
} ] |nW
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publicint getNextIndex(){ a{.q/Tbt
int nextIndex = getStartIndex() + ZXGi> E
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pageSize; ~`C_B]3|
if(nextIndex >= totalCount) z}B39L
return getStartIndex(); ?*%_:fB
else "L:4 7!8
return nextIndex; ,T`,OZm
} t:5-Ro
[ r8 ZAS
publicint getPreviousIndex(){ F,{mF2U*$
int previousIndex = getStartIndex() - Yu>DgMW
? ep#s$i
pageSize; Rh?bBAn8
if(previousIndex < 0) RGE(#
return0; ]Ob|!L(
else ?UZt30|1
return previousIndex; G %6P`:
} a9z#l}IQ
`}$o<CJ
} X
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抽象业务类 ^Aq0<
java代码: `(sb
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/** +t+<?M B
* Created on 2005-7-12 "(^XZAU#W
*/ fq]PKLW'
package com.javaeye.common.business; DS<1"4 b|
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import java.io.Serializable; UtQey ;w
import java.util.List; 9)ALJd,M
>H!Mx_fDL
import org.hibernate.Criteria; _XV%}Xb'
import org.hibernate.HibernateException; X,7y| tb
import org.hibernate.Session; XiE`_%NW
import org.hibernate.criterion.DetachedCriteria; qk1j mr
import org.hibernate.criterion.Projections; G
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import ]R#:Bq!F
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org.springframework.orm.hibernate3.HibernateCallback; HU i?\4
import :TH cI;PG8
4^tSg#!V{
org.springframework.orm.hibernate3.support.HibernateDaoS f'^uuO#x
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upport; [y[d7V9_o
sU ZA!sv
import com.javaeye.common.util.PaginationSupport; N1c=cZDV
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public abstract class AbstractManager extends =|S%Rzsk
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HibernateDaoSupport { xH-d<Ht,7
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privateboolean cacheQueries = false; qTd[DaG#
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privateString queryCacheRegion; MzJCiX^
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publicvoid setCacheQueries(boolean r~t`H*C)}
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cacheQueries){ 9-KhJq%
this.cacheQueries = cacheQueries; C82_)@96
} Gk,Bx1y
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publicvoid setQueryCacheRegion(String \G" S7
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queryCacheRegion){ K,E/.Qe\C
this.queryCacheRegion = rs&]46i/p
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queryCacheRegion; 1 em,/>"
} Z/#_Swv
2/LSB8n|
publicvoid save(finalObject entity){ yB b%#GW
getHibernateTemplate().save(entity); BUO5g8m{
} eUyF<j
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publicvoid persist(finalObject entity){ 8\n3
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getHibernateTemplate().save(entity); pP. _%5
} Z'z)Oo
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publicvoid update(finalObject entity){ "yn~axk7
getHibernateTemplate().update(entity); Gm=qn]c
} *o6}>;
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publicvoid delete(finalObject entity){ ;[v!#+yml
getHibernateTemplate().delete(entity); {VgE07r
} g{8RPw]
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publicObject load(finalClass entity, 2"Os9 KD
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finalSerializable id){ z:Ml;y
return getHibernateTemplate().load :RaQ
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(entity, id); o>el"0rn.h
} l& :EKh
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publicObject get(finalClass entity, d>NGCe
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finalSerializable id){ (!~cOx
return getHibernateTemplate().get hnnB4]c
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(entity, id); YB#fAU
} ]%\,.&=hT
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publicList findAll(finalClass entity){ D31X {dJ
return getHibernateTemplate().find("from q!Du
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" + entity.getName()); %pC<T*f
} Y-VDi.]W
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publicList findByNamedQuery(finalString b IDUa
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namedQuery){ }K {1Bm@S
return getHibernateTemplate O[@!1SKT0
=%Y1] F
().findByNamedQuery(namedQuery); B}e/MlX3M
} w:&""'E
L*@`i ]jl
publicList findByNamedQuery(finalString query, xL}i9ozZ
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finalObject parameter){ @Jt$92i5PS
return getHibernateTemplate Z}W{ iD{
+;N]34>S7
().findByNamedQuery(query, parameter); ]l,BUf-O
} L^J4wYFTO
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publicList findByNamedQuery(finalString query, > p`,
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finalObject[] parameters){ Y
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return getHibernateTemplate HJL! ;i
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().findByNamedQuery(query, parameters); q<3nAE$?=
} z.vQ1~s
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publicList find(finalString query){ A*JOp8\)
return getHibernateTemplate().find J_Lmy7~xbD
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(query); wu
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} Q(|@&83].
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publicList find(finalString query, finalObject cslC+e/
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parameter){ %~rEJB@{
return getHibernateTemplate().find i7x&[b
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(query, parameter); L/k35 x8
} MxTJgY
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public PaginationSupport findPageByCriteria Y}~sTuWU
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(final DetachedCriteria detachedCriteria){ &l(T},-X
return findPageByCriteria ak(s@@k
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(detachedCriteria, PaginationSupport.PAGESIZE, 0);
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} 2/-m-5A
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public PaginationSupport findPageByCriteria g2OnLEF]s
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(final DetachedCriteria detachedCriteria, finalint $LP(\T([
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startIndex){ 92TuuN#{
return findPageByCriteria wL;OQhI
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(detachedCriteria, PaginationSupport.PAGESIZE, d i\.*7l?
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startIndex); &;Ncc,jb
} > ,6
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public PaginationSupport findPageByCriteria dc$zW^i
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(final DetachedCriteria detachedCriteria, finalint kQ\GVI11?
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pageSize, u`ir(JIj]
finalint startIndex){ q<}IO
return(PaginationSupport) KOixFn1
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getHibernateTemplate().execute(new HibernateCallback(){ 7F`\Gz_2
publicObject doInHibernate \VPw3
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(Session session)throws HibernateException { 4LSs WO<@
Criteria criteria = HT7,B(.}
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detachedCriteria.getExecutableCriteria(session); /_{-~0Z=@B
int totalCount = V_i&@<J
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((Integer) criteria.setProjection(Projections.rowCount ^EIuGz1@0
r^k+D<k[7
()).uniqueResult()).intValue(); y&\4Wr9m
criteria.setProjection ("`"?G
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(null); /qdv zv%T
List items = /&6{}n
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criteria.setFirstResult(startIndex).setMaxResults uc9h}QJ*
8UB2 du@?
(pageSize).list(); 0hY3vBQ!
PaginationSupport ps = 5K
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new PaginationSupport(items, totalCount, pageSize, rBJ`=o z
W@!qp
startIndex); mJ%^`mrI
return ps; 5Q"yn2b4
} ?;#Q3Y+
}, true); &5}YTKe}|
} k7uX!}
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public List findAllByCriteria(final 5,xPB5pK
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DetachedCriteria detachedCriteria){ 6TRLHL~B
return(List) getHibernateTemplate q:_:E*o
p$"~vA .
().execute(new HibernateCallback(){ WOPIF~1v
publicObject doInHibernate i59}6u_f
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(Session session)throws HibernateException { YM#'+wl}`
Criteria criteria = 0L;,\&*u
j6s j 2D
detachedCriteria.getExecutableCriteria(session); ESviWCh0Fl
return criteria.list(); Cuylozj$&
} M._h=wX{}
}, true); aj|3(2;Kp
} R(t%/Hvs$
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public int getCountByCriteria(final rvx2{1}I
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DetachedCriteria detachedCriteria){ ]prw=rD
Integer count = (Integer) xM{[~Kh_x
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getHibernateTemplate().execute(new HibernateCallback(){ L@RnLaoQ
publicObject doInHibernate xlcCL?qQj
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(Session session)throws HibernateException { Wrbv<8}%c
Criteria criteria = `pv
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detachedCriteria.getExecutableCriteria(session); shGUG;
return /.s
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/@Jg [na
criteria.setProjection(Projections.rowCount .NWsr*Tel
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()).uniqueResult(); @Y,t]
} =f@71D1
}, true); aQH]hLvs
return count.intValue(); _R0O9sPTO
} !C4)P3k
} 4]}d'x&
} A6z%|d
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用户在web层构造查询条件detachedCriteria,和可选的 "cS7E5-|
-^np"Jk
startIndex,调用业务bean的相应findByCriteria方法,返回一个 TN Z-0
Y q/vym-O5
PaginationSupport的实例ps。 F)=<|,b1
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ps.getItems()得到已分页好的结果集 .`*(#9(M9
ps.getIndexes()得到分页索引的数组 -5os0G80
ps.getTotalCount()得到总结果数 +-x+c:
IxA
ps.getStartIndex()当前分页索引 A?-t`J
ps.getNextIndex()下一页索引 F" G+/c/L
ps.getPreviousIndex()上一页索引 ]=3hH+1 a
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dtQ3iuV %
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 l"&iSq!3=
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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 (RUc>Qi
_x-2tnIxXv
一下代码重构了。 'D[ *|Qcy
M"-53|#:w\
我把原本我的做法也提供出来供大家讨论吧: "<L9-vb
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首先,为了实现分页查询,我封装了一个Page类: 17:7w
java代码: Vs>e"czfm/
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/*Created on 2005-4-14*/ #VZ-gy4$\B
package org.flyware.util.page; 7 }t=Lx(
FIJ]`
/** G{+zKs}~
* @author Joa n>o=RQ2
* s2tNQtq0W
*/ %@I= $8j
publicclass Page { )Zvn{
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f[1>
/** imply if the page has previous page */ Ch=jt*0
privateboolean hasPrePage; |>JRJ"CFE
| m#"
/** imply if the page has next page */ DI :
privateboolean hasNextPage; YRaF@?^Gn
lo7>$`Q
/** the number of every page */ "NV~lJS%
privateint everyPage; V' sq'XB
;M O,HdP;
/** the total page number */ }dq)d.c
privateint totalPage; 4?`*#DPl
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/** the number of current page */ AB.ZmR9|
privateint currentPage; 3|Y.+W
=1VpO{q
/** the begin index of the records by the current m.yt?`
Mn*v&O :
query */ PmUq~YZ7
privateint beginIndex; s8*Q@0
A2nL=9~
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/** The default constructor */ "6WE6zq
public Page(){ !imjfkG
K
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} 2 o5u02x
Uot LJa
/** construct the page by everyPage k~iA'E0-
* @param everyPage +qa^K%K
* */ 5BM rn0
public Page(int everyPage){ J)^Kls\>t
this.everyPage = everyPage; a;G>56iw
} 8J0#lu
GS,}]c=
/** The whole constructor */ nsXyReWka
public Page(boolean hasPrePage, boolean hasNextPage, #@cEJV;5"
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fp$U%uj
int everyPage, int totalPage, 5Noy~;
int currentPage, int beginIndex){ E>1%7"
i<
this.hasPrePage = hasPrePage; <OGXKv@
this.hasNextPage = hasNextPage; V}/AQe2m&
this.everyPage = everyPage; BK foeN)%
this.totalPage = totalPage; AgJPtzs
this.currentPage = currentPage; o[k,{`M0
this.beginIndex = beginIndex; 9t{Iv({6p
} _^NL{R/
<)$JA
/** cx+%lco!
* @return ! ?GW<Rh
* Returns the beginIndex. g-2(W
*/ A~wVY
publicint getBeginIndex(){ DP
&*P/
return beginIndex; bP1]:^ x@W
} M~djX} #\
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/** 0?,%B?A8O
* @param beginIndex '+\.&'A
* The beginIndex to set. *|.-y->
*/ $&FeR*$|g
publicvoid setBeginIndex(int beginIndex){ WTj,9
this.beginIndex = beginIndex; \aGTi
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} ka| 8 _C^z
tQ(gB_
/** X[$FjKZh=F
* @return T']G:jkb
* Returns the currentPage. 0`kaT
?>
*/ z5IdYF?
publicint getCurrentPage(){ =.6JvX<d1*
return currentPage; JrwR:_+|
} Bpdx]5qfK
pytF
K)U
/** oz?pE[[tm
* @param currentPage u*<knZ~ty
* The currentPage to set. j#
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*/ sEEyN3 N
publicvoid setCurrentPage(int currentPage){ dW"=/UW
this.currentPage = currentPage; hH=}<@z
} E9v_6d[
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/** qBcwM=R3P
* @return Et+W LQ6)
* Returns the everyPage. (b;*8
*/ |Fp+9U
publicint getEveryPage(){ NekPl/4
return everyPage; ~Jx0#+z9V
} }^n346^
x10u?@
/** GGkU$qp2~
* @param everyPage 5!iBKOl#D
* The everyPage to set. M%qHf{ B
*/ H+F>#
publicvoid setEveryPage(int everyPage){ %H8s_O
this.everyPage = everyPage; si`h(VD9w
} RP~ hi%A
-)$5[jM]
/** _Xzl=j9[
* @return ^Qa!{9o[
* Returns the hasNextPage. xjg(}w
*/ ~SR9*<
publicboolean getHasNextPage(){ \ 3HB
return hasNextPage; O}mz@-Z
} $ {5|{`
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/** HMPb%'U~
* @param hasNextPage rJ)8KY>
* The hasNextPage to set. T~-OC0
*/ bz\-%$^k
publicvoid setHasNextPage(boolean hasNextPage){ {<y.G1<.
this.hasNextPage = hasNextPage; %Ae43
} ?'+kZ|
;FO( mL (
/**
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* @return O[<0\
* Returns the hasPrePage. B4 +A
*/ V"DilV$v
publicboolean getHasPrePage(){ 4g^Xe-
return hasPrePage; u5E\wRn
} ]c~W$h+F
p^THoF'~T
/** +jN%w{^=
* @param hasPrePage |h* rkLY
* The hasPrePage to set. \ICc?8oL
*/ 1?,1EYT"
publicvoid setHasPrePage(boolean hasPrePage){ n>\2_$uDI
this.hasPrePage = hasPrePage; FoB^iA6e
} nX|]JW
s?~lMm' !
/** =@y
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* @return Returns the totalPage. W~qVZ(G*U
* gjDxgNpa
*/ 4"~l^yK
publicint getTotalPage(){ ?3Y~q;I]O
return totalPage; G7uYkJO
} iTIYq0u|#R
tv'=xDCp
/** b>x03%
* @param totalPage (,OF<<OH
* The totalPage to set. q!4eVg*
*/ ViYfK7Z
publicvoid setTotalPage(int totalPage){ SBh"^q
this.totalPage = totalPage; :hFKmoy#
} GiS:Nq`$(
:jr`}Z%;y
} 4c9a"v
Nn='9s9F?}
0I['UL^!F
=>htX(k}
:b`ywSp`
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Q%!Dk0-)
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个PageUtil,负责对Page对象进行构造: "X,*VQl:
java代码: 7Xf52\7n
ODNZLCB~t
Ge1b_?L_
/*Created on 2005-4-14*/ OWT|F0.1$k
package org.flyware.util.page; E4,
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za!8:(
import org.apache.commons.logging.Log; Yan}H}Oq
import org.apache.commons.logging.LogFactory; E{BX $R_8
\[&&4CN{
/** DPr~DO`b
* @author Joa ,{X}C
* "/nbcQ*s*E
*/ D`R~d;U~
publicclass PageUtil { $8WWN} OC
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privatestaticfinal Log logger = LogFactory.getLog BlfadM;
(\UpJlW
(PageUtil.class); 6uIgyO*;k
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/** qs!A)H#
* Use the origin page to create a new page qL4s@<|~
* @param page FxmHy{JG
* @param totalRecords @Yn+ir0>O
* @return 9DdR"r'7
*/ \03ZE^H
publicstatic Page createPage(Page page, int hBi/lHu'
L7]o^p{g}Q
totalRecords){ qe'RvBz
return createPage(page.getEveryPage(), jN-!1O._G
-2'1KAk-W
page.getCurrentPage(), totalRecords); 1gQ_76Yck
} .$fSWlM;
cx]H8]ch7
/** +kN,OK~
* the basic page utils not including exception RM;Uq>l
8([ MR
handler !
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* @param everyPage WPAT\Al&AE
* @param currentPage \q\"=
* @param totalRecords ZUkM8M$c
* @return page 09qfnQG
*/ c
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publicstatic Page createPage(int everyPage, int WLA&K]
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currentPage, int totalRecords){ O?ODfO+>
everyPage = getEveryPage(everyPage); (D:-p:q.
currentPage = getCurrentPage(currentPage); 3N5@<:2`
int beginIndex = getBeginIndex(everyPage, F^Bk @
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currentPage); @lWYc`>}
int totalPage = getTotalPage(everyPage, 5'( T*"
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totalRecords); NeJ->x,
boolean hasNextPage = hasNextPage(currentPage, a@J/[$5
wJD'q\n
totalPage); 3b|=V
boolean hasPrePage = hasPrePage(currentPage); 'iTY?
]&N>F8.L+
returnnew Page(hasPrePage, hasNextPage, \E[6wB>uN%
everyPage, totalPage, Ot)S\s>
currentPage, Q :.i[
'4_c;](W
beginIndex); F-$!e?,H
} RL$%Vy0
P*H0Hwn;
privatestaticint getEveryPage(int everyPage){ 8+J>jZ
return everyPage == 0 ? 10 : everyPage; }LeS3\+UHl
} mz+UkA'
T@*'}*
privatestaticint getCurrentPage(int currentPage){ Oxa8u e?
return currentPage == 0 ? 1 : currentPage; e`:^7$
} ;>L8&m)R5
k~gOL#$
privatestaticint getBeginIndex(int everyPage, int `a!9_%|8
.rITzwgB
currentPage){ -Lu&bVt<>
return(currentPage - 1) * everyPage; [uK{``"
} N.H<'Q8&
YCQ$X
privatestaticint getTotalPage(int everyPage, int _6V1oe2
reNf?7G+m
totalRecords){ DIw_"$'At
int totalPage = 0; 22=sh;y+2
R :(-"GW'
if(totalRecords % everyPage == 0) J8i,[,KcE
totalPage = totalRecords / everyPage; E3l*_b0
else d#]hqy
totalPage = totalRecords / everyPage + 1 ; X9NP,6
k_!e5c
return totalPage; vzFpXdt
} <e?Eva%t`
tv.<pP9-C
privatestaticboolean hasPrePage(int currentPage){ aWlIq(dU
return currentPage == 1 ? false : true; dJ
m9''T')
} amdgb,vh
0#Lmajs
privatestaticboolean hasNextPage(int currentPage, o{! :N> (
vy*-"=J
int totalPage){ \ ZE[7Ae
return currentPage == totalPage || totalPage == :)D7_[i
p7@R+F\.};
0 ? false : true; |oke)w=gn
} /KX+'@
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tV`=o$`
} J-Tiwl
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 eu9*3'@A
QcW8A ,\q
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 1*Pxndt&
cl2_"O
做法如下: CpmT*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 sqtz^K ROM
n)98NSVDbT
的信息,和一个结果集List: "mf$E|
java代码: )\=xPfs
HyU: BW;
y'`/^>.
/*Created on 2005-6-13*/ 5EcVW|(
package com.adt.bo; xF8n=Lc
%g}d}5s
import java.util.List; T5."3i
L|T?,^
import org.flyware.util.page.Page; e))L&s
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/** xBVOIc[4(
* @author Joa Td|u@l4B
*/ `a4&_`E,p
publicclass Result { (Z(S?`')
KU/r"lMNlU
private Page page; 8YQuq.(>a
7TMq#Pb
private List content; )*;Tt @'y
dA~:L`A|X
/** &,k!,<IF
* The default constructor 3-
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*/ + U5Q/g
public Result(){ B#Ybdp ;
super(); @@Ybg6.+*
} *9EwZwE_K
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/** -[L\:'Gp5
* The constructor using fields 1@}F8&EZ
* hpF_@n
* @param page |l;
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* @param content E+@Q
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*/ 6:#o0OeBP
public Result(Page page, List content){ (BVqmi{
this.page = page; CUI3^;&S
this.content = content; vPNbV
} })/P[^
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/** K6IT$$g
* @return Returns the content. yS
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*/ 1_]X
publicList getContent(){ .n]"vpWm[
return content; _YF>Y=D-
} @ep.wW
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/** :W*yfhLt
* @return Returns the page. D$}8GYq
*/ pux IJ
public Page getPage(){ F]
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return page; Vke<; k-
} */;7Uv7
o8g7wM]M
/** t{]Ew4Y4%O
* @param content 2LtDS?)@
* The content to set. _nMd
*/ hJEd7{n
public void setContent(List content){ 0Qt!w(
this.content = content; u5oM;#{@-
} ]].~/kC^3k
6<];}M_{
/** wXQxZuk[
* @param page 0~qc,-)3
* The page to set. |U|>YA1[b
*/ t eY@)F
publicvoid setPage(Page page){ ^1S{::
this.page = page; VHD+NY/
} -#|;qFD]
} 6'Q{xJe?
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dR S:S_
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2. 编写业务逻辑接口,并实现它(UserManager, g<j)
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UserManagerImpl) 5kiW@{m
java代码: iW` tr
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cRT'?w`}
/*Created on 2005-7-15*/ 6.D|\;9{c
package com.adt.service; Jl{ 0q7b
_Si=Jp][
import net.sf.hibernate.HibernateException; s;VW
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import org.flyware.util.page.Page; <mn[-
_,J+b R+b
import com.adt.bo.Result; F)^0R%{C
m/=nz.
/** :$k*y%Z*N&
* @author Joa r<vMp'u
*/ =1IK"BA2?
publicinterface UserManager { *ub2dH4/
2&1mI>:F
public Result listUser(Page page)throws l f>/
~lj[> |\Oj
HibernateException; ?:"ABkL|+Y
_(N+z.
} A=<7*E
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X)b$CG
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4aXIRu%#7
java代码: &QHJ%c
I C
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/*Created on 2005-7-15*/ k\f
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package com.adt.service.impl; KQ\K:#
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import java.util.List; 2R/|/>T v
f'*-<sSr
import net.sf.hibernate.HibernateException; OC=&!<
FZi@h
import org.flyware.util.page.Page; Pq /5Dy
import org.flyware.util.page.PageUtil; K\K& K~Z
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import com.adt.bo.Result; TLwxP"
import com.adt.dao.UserDAO; c1f"z1Z
import com.adt.exception.ObjectNotFoundException; <],{at` v
import com.adt.service.UserManager; cH5i420;aO
7e"}ojt$
/**
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* @author Joa =D1
*/ SQN?[v
publicclass UserManagerImpl implements UserManager { ~o'1PAW7
Z[?n{vD7
private UserDAO userDAO; f.6>6%l
!ho^:}m
/** (?4%Xtul1
* @param userDAO The userDAO to set. h^3gYL7O6
*/ pD{OB
publicvoid setUserDAO(UserDAO userDAO){ ^j}C]cq{Xg
this.userDAO = userDAO; "^]gI Qc
} xi (@\A
<i~xJi%1#
/* (non-Javadoc) a/J<(sak~X
* @see com.adt.service.UserManager#listUser k|;a"56F
o 4F'z
(org.flyware.util.page.Page) Ln>!4i+-B)
*/ D$ds[if$U,
public Result listUser(Page page)throws `J.,dqGb
5 ^{~xOM5
HibernateException, ObjectNotFoundException { =$'>VPQ
int totalRecords = userDAO.getUserCount(); <6Q^o[L
if(totalRecords == 0) ;<+efYmyc
throw new ObjectNotFoundException -`L`kL<
o#qdgZ
("userNotExist"); j)J |'b|
page = PageUtil.createPage(page, totalRecords); dseI~}
List users = userDAO.getUserByPage(page); Wdd}y`lS
returnnew Result(page, users); <pX?x3-'
} 5%,3)H{;t
{hS!IOM
} OUulG16kK
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bDl:,7;
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 b**vUt\
MzvhE0ab
询,接下来编写UserDAO的代码: %1#\LRA(
3. UserDAO 和 UserDAOImpl: UQ0!tFx
java代码: mb*Yw6q
s<