Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 d;nk>6<|
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 hC4
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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 $Wu|4]o>9
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 55ft,a
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。 _>bk'V7
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分页支持类: .Fx3WryF
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java代码: U02
kt kS$
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package com.javaeye.common.util; C~WWuju'
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import java.util.List; ^Rtxef
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publicclass PaginationSupport { +-T|ov<
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publicfinalstaticint PAGESIZE = 30; $wyPGok
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privateint pageSize = PAGESIZE; e jR_3K^
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privateList items; ~pHuh#>
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privateint totalCount; noLr185
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privateint[] indexes = newint[0]; F8#MI
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privateint startIndex = 0; qO/3:-
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public PaginationSupport(List items, int 4TyzD%pOw
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totalCount){ s IBP$9
setPageSize(PAGESIZE); &M tF
setTotalCount(totalCount); O.Y|},F
setItems(items); XB@i{/6K
setStartIndex(0); ko|M2\
} fqBz"l>5A
x iz+R9p
public PaginationSupport(List items, int stMxlG"d
';}:*nZ//_
totalCount, int startIndex){ Udf\;G@
setPageSize(PAGESIZE); SrGJ#K&%
setTotalCount(totalCount); w
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setItems(items); 0!RP7Sx
setStartIndex(startIndex); mY[*Cj3WJ
} O3)B]!xL
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public PaginationSupport(List items, int /D yig
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totalCount, int pageSize, int startIndex){ s];0-65)
setPageSize(pageSize); -SLk8x
setTotalCount(totalCount); kw} E0uY
setItems(items); Dx=RLiU9
setStartIndex(startIndex); y+= s/c
} q(WGvl^r
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publicList getItems(){ L@jpid95
return items; X\w["!B
} u~VXe
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publicvoid setItems(List items){ qx9;"Ut
this.items = items; Q[%G`;e #
} lxbC 7?O
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publicint getPageSize(){ GT80k]e.
return pageSize; O/$41mK+!
} uhnnjI
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publicvoid setPageSize(int pageSize){ 2yD ?f8P4
this.pageSize = pageSize; [6
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} 8e
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publicint getTotalCount(){ ;CoD5F!
return totalCount; pHye8v4fvi
} tUW^dGo.
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publicvoid setTotalCount(int totalCount){ g;OR{
if(totalCount > 0){ b"`Q&V.
this.totalCount = totalCount; H;@0L}Nu+}
int count = totalCount / xRO9o3
F&^&"(H}
pageSize; :oYSvK7>
if(totalCount % pageSize > 0) %Wm)
count++; s jaaZx1
indexes = newint[count]; ^^24a_+2
for(int i = 0; i < count; i++){ jsF5q~F
indexes = pageSize * E7.{SGH}
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i; oK<H/76x
} 0r[a$p>`
}else{ l}T@Cgt
this.totalCount = 0; %F$]v
} m;IKV,
} F x$W3FIO]
aI}htb{m`
publicint[] getIndexes(){ y5D3zqCG
return indexes; O-pH~E
} 3j[<nBsn.
iCGHcN^3
publicvoid setIndexes(int[] indexes){ KG96;l@'(
this.indexes = indexes; M?<iQxtyb}
} 7fd,I% v
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publicint getStartIndex(){ L$ ^ew0C
return startIndex; usu{1&g
} sYSq >M
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publicvoid setStartIndex(int startIndex){ T
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if(totalCount <= 0) Y(ClG*6 ++
this.startIndex = 0; Nv=% R
elseif(startIndex >= totalCount) $RHw6*COG
this.startIndex = indexes _W,?_"[R=
unnuSW#v=
[indexes.length - 1]; xk,1D
elseif(startIndex < 0) CG J_k?h
this.startIndex = 0; xa
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else{ yM(ezb
this.startIndex = indexes *$JS}Pax
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[startIndex / pageSize]; #"H<k(-Cz
} G[fg!vig#7
} s%m?Yh3
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publicint getNextIndex(){ -:Juxh
int nextIndex = getStartIndex() + V.yDZ"
e;"%h%'
pageSize; [s%uE+``S
if(nextIndex >= totalCount) _?bF;R
return getStartIndex(); G!Y7RjWD
else 8)b*q\O'
return nextIndex; n^|7ycB'
} &s\/Uq
fq):'E)
publicint getPreviousIndex(){ 3#F"UG2,_
int previousIndex = getStartIndex() - 'X_%m~}N
8lCo\T5"
pageSize; :D !/.0
if(previousIndex < 0) )M56vyo
return0; _gCi@uXS3
else 3Ea/)EB]
return previousIndex; _Pl5?5eZj
} lXnv(3j3*s
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} j<w5xY
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抽象业务类 8` WaUB%
java代码: `mN5s q
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/** N_VWA.JHt
* Created on 2005-7-12 irGgo-x
*/ IBh?vh
package com.javaeye.common.business; ksAu=X:
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import java.io.Serializable; iR'Pc3
import java.util.List; <VT|R~
V24FzQ?z:.
import org.hibernate.Criteria; Qf}}/k|)k
import org.hibernate.HibernateException; :HH3=.qAp`
import org.hibernate.Session; (.g?|c
import org.hibernate.criterion.DetachedCriteria; mnq1WU;<
import org.hibernate.criterion.Projections; h)X"<a++N
import }>'1Qg
oUN;u*
org.springframework.orm.hibernate3.HibernateCallback; /nNrvMtv
import .;;:t0PB
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org.springframework.orm.hibernate3.support.HibernateDaoS 'L
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upport; [nB4s+NX
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import com.javaeye.common.util.PaginationSupport; vu_ u\2d
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public abstract class AbstractManager extends wf,w%n
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HibernateDaoSupport { U)qG]RI
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privateboolean cacheQueries = false; 0G#s/u#
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privateString queryCacheRegion; x I(X+d``
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publicvoid setCacheQueries(boolean j55OG~)
<USr$
cacheQueries){ z_t%n<OvK
this.cacheQueries = cacheQueries; <io;d$=}
} e]3b0`E
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publicvoid setQueryCacheRegion(String sN@=Ri?\
ko`KAU<T_
queryCacheRegion){ SfGl*2
this.queryCacheRegion = ?w>-ya
/jd.<r=_I
queryCacheRegion; 4cJka~
} KqzQLu
,h* 'Cs04h
publicvoid save(finalObject entity){ 70T{tB
getHibernateTemplate().save(entity); w72\'
} k\}\>&Zqu
.=/TT|eMS
publicvoid persist(finalObject entity){ ^ <+V[=X
getHibernateTemplate().save(entity); UO_tJN#X
} 5>S)+p
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publicvoid update(finalObject entity){ *T0!q#R
getHibernateTemplate().update(entity); IF<<6.tz
} kZ<"hsh,Y'
>
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publicvoid delete(finalObject entity){ V})b.\"F
getHibernateTemplate().delete(entity); `fq# W#Pu
} '\/|K
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publicObject load(finalClass entity, ac#I$V-
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finalSerializable id){ ?m:,hI
return getHibernateTemplate().load 75*q^ui
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(entity, id); i'uSu8$'*
} vALH!Kh
L31#v$;4
publicObject get(finalClass entity, ] 5:0.$5
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finalSerializable id){ oO&R3zA1d
return getHibernateTemplate().get *QP+p,L*
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(entity, id); mD go@f
} wdQ%L4l
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publicList findAll(finalClass entity){ {9<c*0l
return getHibernateTemplate().find("from +L|-W9"@3
%p8#pt\$7
" + entity.getName()); w)xfP^M#
} i
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publicList findByNamedQuery(finalString Ql{:H5
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namedQuery){ Q;0g
return getHibernateTemplate 3\0,>L9ET@
@XN|R
().findByNamedQuery(namedQuery); M|}V6F_y
} +$
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publicList findByNamedQuery(finalString query, zL/rV<
(Kb_/
finalObject parameter){ 8m 5T
return getHibernateTemplate -^&NwLEv=
HAdDr!/`
().findByNamedQuery(query, parameter); V~"-\@
} ID8u&:
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publicList findByNamedQuery(finalString query, 6QG"~>v7'(
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finalObject[] parameters){ bSj-xxB]e
return getHibernateTemplate c,FZ{O@
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().findByNamedQuery(query, parameters); +CXtTasP
} s|9[=JMG
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publicList find(finalString query){ y4j\y
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return getHibernateTemplate().find ]jgMN7
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(query); Fb\ E39
} D2 X~tl5<
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publicList find(finalString query, finalObject {YF(6wVl
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parameter){ 7,"y!\
return getHibernateTemplate().find F-%Hw
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(query, parameter); p&k%d, *
} SGK
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public PaginationSupport findPageByCriteria %Z+FX,AK
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(final DetachedCriteria detachedCriteria){ =2e{T J/
return findPageByCriteria !4+ FN)
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /B)`pF.n
} o'K= X E
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public PaginationSupport findPageByCriteria <kKuis6h
`wKd##v'@
(final DetachedCriteria detachedCriteria, finalint (Rh$0^)A
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startIndex){ uSUog+i
return findPageByCriteria C2H2*"
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(detachedCriteria, PaginationSupport.PAGESIZE, @]7s`?
{'sp8:$a
startIndex); %\T#Ik~3
} m\G45%m
*R3^:Y&
public PaginationSupport findPageByCriteria < b-OdOg
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(final DetachedCriteria detachedCriteria, finalint +h@ZnFp3
oc;4;A-;`c
pageSize, DO6
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finalint startIndex){ .S[M:<<*
return(PaginationSupport) zE+^WeH|
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getHibernateTemplate().execute(new HibernateCallback(){ [@Mo3]#\
publicObject doInHibernate S4VM(~,o
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(Session session)throws HibernateException { ^ddC a
Criteria criteria = eh}|Wd7J
B*:W`}G]_c
detachedCriteria.getExecutableCriteria(session); ?-JW2 E"uT
int totalCount = Q7-'5s
OmlM9cXm^4
((Integer) criteria.setProjection(Projections.rowCount BvP++,a&Sa
-?w3j9kk>
()).uniqueResult()).intValue(); |f1RhB
criteria.setProjection i?861Hu
Ffig0K+`
(null); }kSP p
List items = ndu$N$7+
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criteria.setFirstResult(startIndex).setMaxResults 'LYN{
PLq]\y
(pageSize).list(); o)+C4f[G4
PaginationSupport ps = AnoA5H
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new PaginationSupport(items, totalCount, pageSize, mFt\xGa
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startIndex); wRg[Mu,Q5
return ps; e!vWGnY
} Zn:]?%afdO
}, true); IZuP{7p$
} Vi#[kn'
wb ^>/
public List findAllByCriteria(final 6Ev+!!znu
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DetachedCriteria detachedCriteria){ V`@/"Dj j
return(List) getHibernateTemplate Z%JAX>v&B
x>+sqFd\
().execute(new HibernateCallback(){ 2M)E1q|a
publicObject doInHibernate `yh][gqVE~
q8MyEoc:n
(Session session)throws HibernateException { \+Y5b}
Criteria criteria = ^UBzX;|p
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detachedCriteria.getExecutableCriteria(session); #vc!SI
return criteria.list(); MzF,is
} F~/~_9RJ
}, true); rpc;*t+z
} F^&@[k7WW
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public int getCountByCriteria(final BwAmNW&i
qp{~OW3
DetachedCriteria detachedCriteria){ nfh<3v|kvR
Integer count = (Integer) !QCErE;r
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getHibernateTemplate().execute(new HibernateCallback(){ pZ]&M@Ijp
publicObject doInHibernate <)
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(Session session)throws HibernateException { SNf~%B?`L
Criteria criteria = &yI>A1
Oj8D+sC{
detachedCriteria.getExecutableCriteria(session); $`P]%I}
return :lu "14
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criteria.setProjection(Projections.rowCount #mD_<@@
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()).uniqueResult(); }{mS"
} %vbov}R
}, true); _+Z5qUmQ
return count.intValue(); !wC(
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} /T2 v`Li
} ExF6y#Y G<
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用户在web层构造查询条件detachedCriteria,和可选的 HkY#i;%N
i-.AD4
startIndex,调用业务bean的相应findByCriteria方法,返回一个 2b Fr8FUt-
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PaginationSupport的实例ps。 ,eSpt#M
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ps.getItems()得到已分页好的结果集 ?)Je%H
ps.getIndexes()得到分页索引的数组 7>F [7_
ps.getTotalCount()得到总结果数 .3#Xjhebvu
ps.getStartIndex()当前分页索引 `aA)n;{/2u
ps.getNextIndex()下一页索引 "~KTLf
ps.getPreviousIndex()上一页索引 |io)?`pj
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 P 6({wx
7~;)N$d\
,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 xrI9t?QaCb
d%K{JkD-
一下代码重构了。 ca5;Z@t$S
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我把原本我的做法也提供出来供大家讨论吧: c2L\m*^o
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首先,为了实现分页查询,我封装了一个Page类: dp4vybJ
java代码: /%)(Uz
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/*Created on 2005-4-14*/ Z~[eG"6zI
package org.flyware.util.page; w c\`2(
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/** C0/G1\
* @author Joa KTwP.!<v
* U#<{RqY
*/ 8k+k\V{
publicclass Page { Tt=;of{
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/** imply if the page has previous page */ @ZrNV*&<
privateboolean hasPrePage; Hs{x Z:
tu/4
/** imply if the page has next page */ -BWWaL
privateboolean hasNextPage; =NSunW!
ly6dl
/** the number of every page */ [Dmf.PUe
privateint everyPage; x(p/9$.#
m\E=I5*/
/** the total page number */ `cIeqp
privateint totalPage; E,cQ9}/
yU"#2 *C
/** the number of current page */ r;E5e]w*-
privateint currentPage; V#R; -C
ZI8@ 6 L\
/** the begin index of the records by the current /!y;h-
P#
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query */ lHHx D
privateint beginIndex; px(~ZZB"
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A
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/** The default constructor */ M
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public Page(){ J)|I/8!#
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} 2izBB,# "
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VP
/** construct the page by everyPage ?6L8#"=
* @param everyPage 9e}%2,
* */ de[NIDA;`
public Page(int everyPage){ 0-57_";%Q
this.everyPage = everyPage; zQUNvPYM
} P"Z1K5>2L
g@pK9R%wH<
/** The whole constructor */ J HV
public Page(boolean hasPrePage, boolean hasNextPage, Q'?VLv|@
$ f||!g
rFUd
int everyPage, int totalPage, :LC3>x`:
int currentPage, int beginIndex){ IWI$@dng6
this.hasPrePage = hasPrePage; x?od_M;*8;
this.hasNextPage = hasNextPage; UPPlm\wb*
this.everyPage = everyPage; WP=uHg
this.totalPage = totalPage; 6&L;Sw#Dg
this.currentPage = currentPage; e AaS }g
0
this.beginIndex = beginIndex; ~-uDN)
} w'7J`n:{]
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/** JNP6qM
* @return ^t$uDQ[hA
* Returns the beginIndex. ;Cjj_9e,:
*/ dxH .
publicint getBeginIndex(){ y(E<MRd8V
return beginIndex; Z|)1 ftcC
} #&?}h)Jr'
4r86@^c*
/** _'^_9u G
* @param beginIndex g_?Q3
* The beginIndex to set. )n[=)"rf
*/ DbtkWq%
publicvoid setBeginIndex(int beginIndex){ 6\.LG4@LO
this.beginIndex = beginIndex; \'|t>|zhp
} n-,mC/4
&qIdT;^=I
/** fKtlfQG
* @return tx Qr|\4k
* Returns the currentPage. a:4!z;2
|
*/ i CB:p
publicint getCurrentPage(){ !1UZ<hq
return currentPage; H^vA}F`
} 4$U^)\06W
/;!I.|j
/** Xn>>hzj-x?
* @param currentPage pRUQMPn (
* The currentPage to set. 'Z%1Ly^b
*/ ->7zVAX
publicvoid setCurrentPage(int currentPage){ 0F%?<:
&
this.currentPage = currentPage; yL
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} O`aNNy
\MPbG$ ^
/** 2]FRIy
d
* @return tCPK_Wws?Z
* Returns the everyPage. _j*I\
*/ fr$6&HDZ9
publicint getEveryPage(){ ;vbMC74J#
return everyPage; ""_B3'
} A5]yC\*zt
e<FMeg7n
/** Z`zLrXPD)
* @param everyPage 4X+I2CD
* The everyPage to set. ]\k&
l
['
*/ <'7s3
publicvoid setEveryPage(int everyPage){ x"cB8bZ!$
this.everyPage = everyPage; !\O!Du
} }U4mXkZF
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/** PtzT><
* @return dJdOh#8+Xi
* Returns the hasNextPage. _N>#/v)Yi
*/ (Jk[%_b>_
publicboolean getHasNextPage(){ >$)~B4
return hasNextPage; Cb.M
} tF./Jx]_
6UL9+9[C
/** BMV\@Sg
* @param hasNextPage 9wO2`e )
* The hasNextPage to set. bD|VT
*/ AN|f:259
publicvoid setHasNextPage(boolean hasNextPage){ !$!%era`
this.hasNextPage = hasNextPage; S2W@;XvV
} /^bU8E&^M
475g-t2"@
/** |YfJ#Agm+
* @return [X8EfU}
* Returns the hasPrePage. >l=^3B,j
*/ 'T3xZ?*q=
publicboolean getHasPrePage(){ vL^ +X`.td
return hasPrePage; '
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} ~ tN/
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/** @L0)k^:
* @param hasPrePage |L:X$oM
* The hasPrePage to set. 02T'B&&~
*/ P97i<pB Y_
publicvoid setHasPrePage(boolean hasPrePage){ q9a6s{,
this.hasPrePage = hasPrePage; FP*kA_z$
} 2t45/:,
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/** _5$L`&
* @return Returns the totalPage. i*A_Po
* GxC\Nj#
*/ raU_Z[
publicint getTotalPage(){ ziM@@$.F
return totalPage; kmtkh"
} Z5EII[=$o
^gR~~t;@
/** \b$Y_
* @param totalPage GJHJ?^%
* The totalPage to set. f;Ijl 0d@
*/ p1mAoVxR
publicvoid setTotalPage(int totalPage){ && PZ;
this.totalPage = totalPage; 7 `c!
} ]v]:8>N
aYWUwYB$
} /~c9'38
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1\)lD(J\C
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N%e^2O)
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 4QT)f
*Ue#Sade
个PageUtil,负责对Page对象进行构造: $'<$:;4b3
java代码: VRSBf;?
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/*Created on 2005-4-14*/ ]6O(r)k
package org.flyware.util.page; ZW@cw}
<JvYCWX`
import org.apache.commons.logging.Log; #MiO4zXgd
import org.apache.commons.logging.LogFactory; x;LO{S4Z
roe_H>
/** B[+b%a3
* @author Joa +~M.VsX
* If8
^
*/ Xr88I^F;
publicclass PageUtil { ilZ5a&X;
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privatestaticfinal Log logger = LogFactory.getLog s*eM}d.p
Z^mQb2e.
(PageUtil.class); IMpL+W.
^v:XON<
/** l Ttc#
* Use the origin page to create a new page n,_9Eh#WD
* @param page O-P`HKr
* @param totalRecords Ln/*lLIOb
* @return `R lWhdE
*/ u^x<xw6f
publicstatic Page createPage(Page page, int x@pzgqi3
s5MG#M 9
totalRecords){ u9]M3>
return createPage(page.getEveryPage(), I7t}$S6
y
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page.getCurrentPage(), totalRecords); :X7O4?ww
} /1= x8Sb
rm|,+{
/** m93{K7O2e
* the basic page utils not including exception GW%!?mJ
Vn_>c#B
handler OGq=OW
* @param everyPage Y'R/|:YL@
* @param currentPage >gn@NJ2 N
* @param totalRecords ]J/;Xp
* @return page ygUX ]*m!
*/ CL t(_!q
publicstatic Page createPage(int everyPage, int VwarU(*
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currentPage, int totalRecords){ #ZHKq7
everyPage = getEveryPage(everyPage); 6r[pOl:
currentPage = getCurrentPage(currentPage); `;m0GU68
int beginIndex = getBeginIndex(everyPage, SLvo)`Nc3-
(@O,U
currentPage); N;=J)b|9
int totalPage = getTotalPage(everyPage, Us>
u(ETc*D]
totalRecords); EvA8<o
boolean hasNextPage = hasNextPage(currentPage, a<((\c_8G
R m2M
totalPage); F^=y+}]=
boolean hasPrePage = hasPrePage(currentPage); .l,NmF9
-}8r1jQH;
returnnew Page(hasPrePage, hasNextPage, 'w|N}
4
everyPage, totalPage, vQDR;T"]
currentPage, 90H/Txq
)>;387'Y
beginIndex); &G3$q,`H
} fRzJiM{
Y`xAJ#=
,i
privatestaticint getEveryPage(int everyPage){ T%YN(f
return everyPage == 0 ? 10 : everyPage; 4!?4Tc!X
} a4q02 cV
P rv=f@
privatestaticint getCurrentPage(int currentPage){ +bWo{
return currentPage == 0 ? 1 : currentPage; KkR.p,/
} Lk-h AN{[
}F3}"Ik'L
privatestaticint getBeginIndex(int everyPage, int +]Z*_?j9{
t
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currentPage){ QxBH{TG
return(currentPage - 1) * everyPage; ya;(D 8x)
} Jf@Xz7{z
q+lCA#Sx
privatestaticint getTotalPage(int everyPage, int !~-@sq
^)3=WD'!
totalRecords){ ,^@/I:
int totalPage = 0; RF\h69]:I
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if(totalRecords % everyPage == 0) H\|H]: CE
totalPage = totalRecords / everyPage; Jb8%A@Z+
else eHyIFoaC/
totalPage = totalRecords / everyPage + 1 ; F}5skD=
Z>W&vDeuN
return totalPage; z7Z!wIzJ
} pWb8X}M
hCj8y.X|E(
privatestaticboolean hasPrePage(int currentPage){ mWVq>~
return currentPage == 1 ? false : true; )Qo^Mz
} }9+Vf'u|l
RRGs:h@;
privatestaticboolean hasNextPage(int currentPage, krXU*64
u>2opI~m
int totalPage){ yJ8_<A
return currentPage == totalPage || totalPage == !1bATO:x
+1Rz +
0 ? false : true; e&9v`8}
} Js9EsN%
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} @^b>S6d"
u4[rA2Bf8E
jZqCM{
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w|ct="MG
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。 <I2~>x5db
v0%FG9Gk
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 7+P-MT
ZVCa0Km
做法如下: D#X&gE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 (i]0IYMXy*
z+Ej`$E{lD
的信息,和一个结果集List: {=P}c:iW
java代码: W!a'KI'
FOuPj+}F
B)&z% +
/*Created on 2005-6-13*/ 0-Wv$o[
package com.adt.bo; |b|bL 7nx
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import java.util.List; :U'Oc3l#Y
c+UZ UgP
import org.flyware.util.page.Page; ~fz9PoC
RM!VAFH
/** WAb@d=H{+>
* @author Joa e]7J_9t@
*/ ov'C0e+o
publicclass Result { a &hj|
#:[CF:
private Page page; 9:*a9xT,
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private List content; VCUsvhI
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/** (KphAA8
* The default constructor *Di ;Gf@
*/ B|-W
public Result(){ 8?t}S2n2
super(); oD%B'{Zs4
} ;VgB!
Yg]!`(db
/** Kd3EZo.
* The constructor using fields HhB'
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* w?M` gl8r
* @param page >jm^MS=
* @param content x)e(g}n
*/ Xxs0N_va&
public Result(Page page, List content){ b|g=&T:pp
this.page = page; r} a,
this.content = content; 1K{hj%
} h%U,g
9_
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/** ]bAw>1,NVD
* @return Returns the content. v`~egE17
*/ HJOoCf
publicList getContent(){ 3xpygx9
return content; bU_P@GKB
} S| l%JM^
:n$?wp
/** $Q56~AP
* @return Returns the page. %Yny/O\e%
*/ ||rZ+<
public Page getPage(){ eu?DSad
return page; s"0Hz"[^=
} r?=3TAA
nb U?:=P
/** >2LlBLQ
* @param content Trml?zexD
* The content to set. vOBXAF
*/ ^ V8?6E
public void setContent(List content){ wL"
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this.content = content; >Gr,!yP
} Xe<kdB3
2<^eVpNJR
/** cK1RmL"3
* @param page cAzlkh
* The page to set. MF4B 2d
*/ r$;u4FR
publicvoid setPage(Page page){ p`oHF 5
this.page = page; &uG@I=}TIY
} cmbl"Pqy1
} F!ra$5u
@i@f@.t
r_M5:Rz
hE}y/A[
9I*`~il>{
2. 编写业务逻辑接口,并实现它(UserManager, `'/1Ij+
>twog}%
UserManagerImpl) 6g%~~hX
java代码: ,\0>d}eh!
F;)qM|7
p (x<h
/*Created on 2005-7-15*/ hg}R(.1K=
package com.adt.service; ~X1<x4P\
^97\TmzP{
import net.sf.hibernate.HibernateException; l =^ ^l`
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import org.flyware.util.page.Page; D>"!7+t|@a
iLJBiZ+
import com.adt.bo.Result; Ox"SQ`nSj'
%1%@L7wP>
/** ]j^rJ|WTH
* @author Joa OJPi*i 5*
*/ c:_dW;MJ0
publicinterface UserManager { ;F\sMf{
>&uR=Yd
public Result listUser(Page page)throws >I;J!{
3Vb/Mn!k
HibernateException; Zi ;7.P qL
VyxX5Lrj
} F=~LVaF/_
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java代码: =FXq=x%9+
t{Gc,S!]5
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/*Created on 2005-7-15*/ _f<#+*y
package com.adt.service.impl; OiMr,
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import java.util.List; DO9_o9'
|bv7N@?e
import net.sf.hibernate.HibernateException; \-R\xL
Z6_E/S
import org.flyware.util.page.Page; nO .:f
import org.flyware.util.page.PageUtil; K.: :P84m;
3B[u2o>
import com.adt.bo.Result; ;$rh&ET
import com.adt.dao.UserDAO; %3 VToj@`>
import com.adt.exception.ObjectNotFoundException; i$S*5+
import com.adt.service.UserManager; Kma-W{vGD
;@G5s+<l
/** h&m4"HBL_
* @author Joa $o>6Io|D
*/ L s(l
publicclass UserManagerImpl implements UserManager { udGZ%Mr_
qq[Enf|/y
private UserDAO userDAO; Ai.^~#%X
Bz*6M
/** T{mIkp<
* @param userDAO The userDAO to set. Cw]bhaG
g
*/ ThJ`-Ro
publicvoid setUserDAO(UserDAO userDAO){ ^<QF*!
this.userDAO = userDAO; k|[86<&[
} geEETb}+y
$'
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/* (non-Javadoc) Ts
1
* @see com.adt.service.UserManager#listUser QeipfK+me
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(org.flyware.util.page.Page) hR%2[lBn!]
*/ 3[}w#n1
public Result listUser(Page page)throws V.Qy4u7m
Xo~kB)|,
HibernateException, ObjectNotFoundException { pQ9~^
int totalRecords = userDAO.getUserCount(); ^fxS=Qs+
if(totalRecords == 0) 8PwPI%Pb
throw new ObjectNotFoundException 2)47$eu
o&U/e\zy
("userNotExist"); $JZ}=\n7
page = PageUtil.createPage(page, totalRecords); !t+eJj
List users = userDAO.getUserByPage(page); @c^g<
returnnew Result(page, users); <;':'sW
} NM&R\GI
&xMQ
}
o
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b<"LUM*;
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 b{hdEb
i@hW" [A
询,接下来编写UserDAO的代码: C{P:1ELYXH
3. UserDAO 和 UserDAOImpl: W"ldQ
java代码: $>!tpJw
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vN3uLz'<
/*Created on 2005-7-15*/ [-'LJG Wb<
package com.adt.dao; ^9A,j}>o-
V"R ,omh
import java.util.List; cHk ?$
c$52b4=a
import org.flyware.util.page.Page; cy!;;bB
FG6mh,C!
import net.sf.hibernate.HibernateException; ipn0WQG
#x[3@zP.
/** h$rk]UM/Q
* @author Joa w@&(=C
*/ AG(Gtvw
publicinterface UserDAO extends BaseDAO { i+eDBg6
4'BZ +A,p
publicList getUserByName(String name)throws pQ yH`
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HibernateException; 1QJB4|5R#
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publicint getUserCount()throws HibernateException; ".Sa[A;~
YB3?Ftgw
publicList getUserByPage(Page page)throws RLr^6+v)U
!+Us) 'L
HibernateException; 19 <Lgr
`}|$eF&
} `as6IMqJD
Z}s56{!.
4]mAV\1
}N%uQP#I
D/]
java代码: )ME'qA3K
2!;U.+(
Ki(
/*Created on 2005-7-15*/ /aX5G
package com.adt.dao.impl; Xgyi}~AoaU
z]bcg$m
import java.util.List; =Xh*w
$61j_;WF`
import org.flyware.util.page.Page; $3je+=ER
0>)F+QC
import net.sf.hibernate.HibernateException; gL}x|Q2`
import net.sf.hibernate.Query; }Z3+z@L
*#g[
jl4
import com.adt.dao.UserDAO; Ft^+P*
pIP^/H
/** N@G~+GCxL
* @author Joa (7J (.EG2e
*/ d<+@cf_9
public class UserDAOImpl extends BaseDAOHibernateImpl {&d )O
`;\~$^sj}
implements UserDAO { E
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VSW"/{Lp
/* (non-Javadoc) Zz@wbhMV
* @see com.adt.dao.UserDAO#getUserByName bFtzwa5Gc
{u{8QKeC
(java.lang.String) jz"-E
*/ YMD&U
publicList getUserByName(String name)throws atmTI`i
To@77.'
HibernateException { 6BIr{SY
String querySentence = "FROM user in class }hA h'*(
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com.adt.po.User WHERE user.name=:name"; E{W(5.kb;i
Query query = getSession().createQuery _ !H8j/b
M&~cU{9c
(querySentence); !(>yB;u
query.setParameter("name", name); .Mu]uQUF
return query.list(); F=l. 2t*9
} Xl\yOMfp
6
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/* (non-Javadoc) H!vX#
* @see com.adt.dao.UserDAO#getUserCount() >a$b4
pvh
*/ ,J ZM%f
publicint getUserCount()throws HibernateException { 2X!!RS>qg
int count = 0; I^itlQ
String querySentence = "SELECT count(*) FROM BOf)27)
IM$I=5ye
user in class com.adt.po.User"; C3GI?|b
Query query = getSession().createQuery }j6<S-s~
ZKco
(querySentence); _ pKWDMB$z
count = ((Integer)query.iterate().next m.DC
JDj^7\`
()).intValue(); $3D#U^7i
return count; Bn?MlG;aA
} AB")aX2%E
(3fU2{sm
/* (non-Javadoc) 9G"-~C"e3
* @see com.adt.dao.UserDAO#getUserByPage z1`z
k0
)*I%rN8b
(org.flyware.util.page.Page) 0f3C;u-q-
*/ HC\\w-`<
publicList getUserByPage(Page page)throws 8@J5tFJ&%
l5fF.A7TT
HibernateException { rtY4B~_
String querySentence = "FROM user in class ]/y69ou
:MbD=sX
com.adt.po.User"; QB|D_?]
Query query = getSession().createQuery rN5;W
ga+Z6|t
(querySentence); [$P.ek<
query.setFirstResult(page.getBeginIndex()) qk=0ovUzg
.setMaxResults(page.getEveryPage()); Hg%8Q@
return query.list(); ;OD+6@Sr
} -|x YT+?%
OJ2I (8P
} bJ6@
B<
bhg
OLh#
Xsit4Ma
4[^lE?+
>W7IWhm3
至此,一个完整的分页程序完成。前台的只需要调用 Wk*t-
_E<