Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3D}Pa
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 imc1rY!~'
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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 {[pzqzL6
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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 =Jax T90x
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分页支持类: ]bP1gV(b-
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java代码: 719lfI&s
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package com.javaeye.common.util; bn:74,GeyK
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import java.util.List; J?Bj=b
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publicclass PaginationSupport { L[voouaqm
@$fvhEkrT@
publicfinalstaticint PAGESIZE = 30; bx%Ky0Z
oH(a*i
privateint pageSize = PAGESIZE; zDf96eK
;$vVYC
privateList items; S&F[\4w5]
Df@b;-E
privateint totalCount; m1D,#=C,_
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privateint[] indexes = newint[0]; .I Io
,`!>.E.
privateint startIndex = 0; \E1CQP-
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public PaginationSupport(List items, int f5z*AeI
2)Q%lEm`SP
totalCount){ 6!@p$ pm)a
setPageSize(PAGESIZE); R8>17w.
setTotalCount(totalCount); X`C ozyYuD
setItems(items); KK?R|1VK9
setStartIndex(0); u
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} gI/SA
0.wNa~_G|
public PaginationSupport(List items, int W0S\g#
bg2r
totalCount, int startIndex){ vt#&YXu{A
setPageSize(PAGESIZE); zmg
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setTotalCount(totalCount); Am<){&XT
]
setItems(items); qzWnl[3
setStartIndex(startIndex); +^q-v-
} 8&:dzS
V#+M lN
public PaginationSupport(List items, int _D{{C
%_(^BZd
totalCount, int pageSize, int startIndex){ _ xM}*_<VP
setPageSize(pageSize); Lh-+i
setTotalCount(totalCount); Tdxc%'l
setItems(items); )`#SMLMy~
setStartIndex(startIndex); (g>&ov(d
} ll
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a|ZJzuqo
publicList getItems(){ v2ab84
C*
return items; L*6>S_l[
} lvG+9e3+
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publicvoid setItems(List items){ 8w ]'U
this.items = items; 2]5ux!Lqln
} G%dzJpC(
Z*Fn2I4
publicint getPageSize(){ _=K\E0I.m
return pageSize; ),@m
3wQ
} 6 u,w
cS>xT cj
publicvoid setPageSize(int pageSize){ c3)6{
this.pageSize = pageSize; }-@h H(
} fM3ZoH/
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publicint getTotalCount(){ R=C+]
return totalCount; "d*-k R
} brdY97s4
n],"!>=+
publicvoid setTotalCount(int totalCount){ @Ll^ze&HI
if(totalCount > 0){ \98|.EG
this.totalCount = totalCount; {A\y4D@
int count = totalCount / pYj}
hM[I}$M&O
pageSize; 1`9'.w+r
if(totalCount % pageSize > 0) KkSv23In
count++; h`D+NZtWm
indexes = newint[count]; d z\yP
v~
for(int i = 0; i < count; i++){ +
7nA; C
indexes = pageSize * #U6~U6@
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i; B7n1'?
} Lw6}bB`}
}else{ HHZrovA#
this.totalCount = 0; Ku8qn\2"
} QaLVIsnfN
} DuRC1@e
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publicint[] getIndexes(){ 9-.`~v
return indexes; 5r^u7k
} H6Kt^s<6xu
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publicvoid setIndexes(int[] indexes){ GC@U['
this.indexes = indexes; K>TvM&
} npcL<$<6X
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publicint getStartIndex(){ Px`z$~*B:
return startIndex; > M4QEv
} (o8?j^ -v
;h4w<OqcM
publicvoid setStartIndex(int startIndex){ | EFbT>
if(totalCount <= 0) 8'0KHn{#
this.startIndex = 0; `7_s@4:
elseif(startIndex >= totalCount) `%.x0~ih
this.startIndex = indexes k&o1z'<C
gP=@u.
[indexes.length - 1]; &z"yls
elseif(startIndex < 0) o
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this.startIndex = 0; ETaLE[T%1
else{ ^S^7u
this.startIndex = indexes ?Q: KW
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[startIndex / pageSize]; 1y.!x~Pi,
} y73@t$|
} ]ChN]>o
s
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publicint getNextIndex(){ k^\>=JTq=
int nextIndex = getStartIndex() + Q".AmHn
MU~nvs;:
pageSize; FhMl+Ou
if(nextIndex >= totalCount) ,IG?(CK|
return getStartIndex(); -42jeJS
else K[i|OZWu
return nextIndex; ysQ8==`38i
} CfjVx
x2z%J,z@4
publicint getPreviousIndex(){ >=ng?
int previousIndex = getStartIndex() - g/ x\#W
/qO?)p3gk
pageSize; EXT_x q
if(previousIndex < 0) Z#062NL
"
return0; fQ~YBFhlr
else 4vf,RjB-5
return previousIndex; !e:HE/&>i
} WAp#[mW.fx
*M()z.N
} b+mh9q'5E
AME6Zu3Y
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抽象业务类 W\<p`xHk
java代码: oF#]<Z\
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/** 1|%C66f^
* Created on 2005-7-12 &B>YiA
*/ UP |#WegO
package com.javaeye.common.business; HtGGcO'bqg
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import java.io.Serializable; s~Od(,K
import java.util.List; zmh3
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F#$[jh$
import org.hibernate.Criteria; ejC== Fkc
import org.hibernate.HibernateException; X8=sk
import org.hibernate.Session; *27*&&=)H
import org.hibernate.criterion.DetachedCriteria; m'suAj0
import org.hibernate.criterion.Projections; WjvD C"
import gDjs:]/YR
XxEKv=_bc
org.springframework.orm.hibernate3.HibernateCallback; ,-{2ai_
import $@:z4S(
p*Hbc|?{Q&
org.springframework.orm.hibernate3.support.HibernateDaoS X?Mc"M
c`h/x>fa
upport; C/x<_VJzN/
(3+:/,{'$
import com.javaeye.common.util.PaginationSupport; sz%'=J~!V
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public abstract class AbstractManager extends zE\@x+k.
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HibernateDaoSupport { O8%Y .SK
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privateboolean cacheQueries = false; 9K5[a^q|My
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privateString queryCacheRegion; ');QmN%J
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publicvoid setCacheQueries(boolean _o-D},f*e
_oJq32
cacheQueries){ L(i*v5?
this.cacheQueries = cacheQueries; *R^u lp[W
} h_Cac@F0
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publicvoid setQueryCacheRegion(String '@<aS?@!t
pu +"bq
queryCacheRegion){ O[[#\BL
this.queryCacheRegion = s`:-6{E
@dj2#
queryCacheRegion; P7i
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} p x1{=~V/
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publicvoid save(finalObject entity){ H#B~h4#
getHibernateTemplate().save(entity); ,pz^8NJAI
} <H)I06];
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publicvoid persist(finalObject entity){ ymLhSF][
getHibernateTemplate().save(entity);
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} ?E?dg#yk
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publicvoid update(finalObject entity){ yprf
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getHibernateTemplate().update(entity); @i[z4)"S
} `9
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publicvoid delete(finalObject entity){ ,S i23S\
getHibernateTemplate().delete(entity); $MEKt}S
} e)~7pXYV)
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publicObject load(finalClass entity, @P^8?!i+
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finalSerializable id){ RqIic\aD
return getHibernateTemplate().load /f7Fv*z/
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(entity, id); %:eepG|
} |*im$[g=-
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publicObject get(finalClass entity, <|s9@;(I
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finalSerializable id){ "s]c79t
return getHibernateTemplate().get bX:ARe
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(entity, id); n(gw%w+\7
} I
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publicList findAll(finalClass entity){ 9@-^!DBM
return getHibernateTemplate().find("from P!{
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I T)rhi:
" + entity.getName()); -VESe}c:nQ
} mk;l;!*T8
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publicList findByNamedQuery(finalString `V@{#+X
u $N2uFc
namedQuery){ VR>;{>~
return getHibernateTemplate $^Dx4:k<2
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().findByNamedQuery(namedQuery); pNo<:p
} 05\A7.iy
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publicList findByNamedQuery(finalString query, h,q%MZ==^s
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finalObject parameter){ ;K:)R_H
return getHibernateTemplate aZYa<28?L%
dE*n!@
().findByNamedQuery(query, parameter); =>Vo|LBoe
} )POuH*j
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publicList findByNamedQuery(finalString query, 1FS Jqad
+'H_sMmi{
finalObject[] parameters){ [e
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return getHibernateTemplate 1.0S>+^JE
Z,Z34:-
().findByNamedQuery(query, parameters); )z9)oM\
} 9}FWO&LiB
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publicList find(finalString query){ c,1Yxg]|
return getHibernateTemplate().find kmM1)- v
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(query); wj/\!V!
} (z0S5#g
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publicList find(finalString query, finalObject nJ#uz:(w,
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parameter){ s% "MaDz
return getHibernateTemplate().find qWf7k+7G
pq6}q($Rk
(query, parameter); $
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} 9cAb\5c|
,
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public PaginationSupport findPageByCriteria ]l>)Di#*o
N %-Cp)
(final DetachedCriteria detachedCriteria){ r>S?,qr
return findPageByCriteria KvC`6
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?yF)tF+<
} k+2~=#
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public PaginationSupport findPageByCriteria &AmTXW
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(final DetachedCriteria detachedCriteria, finalint vBUx)l
RF
4u\ \
startIndex){ "#2z
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return findPageByCriteria S*6P=O*
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(detachedCriteria, PaginationSupport.PAGESIZE, o~,dkV
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startIndex); kC"<4U
} <8p53*a
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public PaginationSupport findPageByCriteria Z9s tB>?
]lzt"[
(final DetachedCriteria detachedCriteria, finalint "jzU`
!CROc}
pageSize, jQzq(oDQw
finalint startIndex){ rl9YB %P
return(PaginationSupport) AoL4#.r3H
[Z|R-{"
getHibernateTemplate().execute(new HibernateCallback(){ '$W@I
publicObject doInHibernate s)#FqB8
Qwb=N
(Session session)throws HibernateException { *D1^Se
Criteria criteria = mc;Z#"kf
-
*!R
detachedCriteria.getExecutableCriteria(session); Tm5]M$)
int totalCount = 9D:p~_"g
ppjd.
((Integer) criteria.setProjection(Projections.rowCount kt.z,<w5O
7jT]J
()).uniqueResult()).intValue(); 1q<BYc+z
criteria.setProjection D(D:/L8T,
Rz1&(_Ps
(null); *VH!<k[n
List items = fn
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.v%H%z~Rl#
criteria.setFirstResult(startIndex).setMaxResults *SQ hXTn
~h6aw
(pageSize).list();
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PaginationSupport ps = >S3iP?V7
9S@PY_ms
new PaginationSupport(items, totalCount, pageSize, 6Yebc_, R
eKNZ?!c=
startIndex); :}0y[qc3
return ps; _Iy0-=G
} NARW3\
}, true); y|U3
} b[Sd$ACd
j2SJ4tB /
public List findAllByCriteria(final * F%Wf
oCdWf63D
DetachedCriteria detachedCriteria){ b;# 3X)
return(List) getHibernateTemplate wl #Bv,xf
^AtAfVJN0
().execute(new HibernateCallback(){ :zZK%}G<
publicObject doInHibernate ]7n+|@3x
2`I"
QU
(Session session)throws HibernateException { %Kx:'m%U
Criteria criteria = +uKh]RP
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F
detachedCriteria.getExecutableCriteria(session); PXG)?`^NX
return criteria.list(); E&P'@'Yk
} NL
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}, true); ;@GlJ
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} yB\}e'J^
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public int getCountByCriteria(final H=[eO
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DetachedCriteria detachedCriteria){ :@{(^}N8u
Integer count = (Integer) JsI`#
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getHibernateTemplate().execute(new HibernateCallback(){ |u8IQR'B
publicObject doInHibernate X&fM36o7
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(Session session)throws HibernateException { wl H6
Criteria criteria = z[X>>P3<n
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detachedCriteria.getExecutableCriteria(session); p'fq&a+
return M_*"g>Z
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criteria.setProjection(Projections.rowCount yEIM58l
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()).uniqueResult(); hRTw8-wy:
} w%R(*,r6
}, true); J7q^4M+o:
return count.intValue(); @igr~hJ
} .Nz2K[
} fVx<f.xuW
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用户在web层构造查询条件detachedCriteria,和可选的 pA7&
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |`[0U
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PaginationSupport的实例ps。 tIfA]pE
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ps.getItems()得到已分页好的结果集 _0dm?=
ps.getIndexes()得到分页索引的数组 \Fg%V>
ps.getTotalCount()得到总结果数 dPZrX{ c
ps.getStartIndex()当前分页索引 NQ~keN
ps.getNextIndex()下一页索引 5e=9~].7
ps.getPreviousIndex()上一页索引 Hy=';Ccn}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ?D?_D,"C
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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 oS3'q\
1) 7n
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一下代码重构了。 Ahl-EVIr<
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我把原本我的做法也提供出来供大家讨论吧: k|V%*BvY>
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首先,为了实现分页查询,我封装了一个Page类: D! TFb E
java代码: &zkuL
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/*Created on 2005-4-14*/ &[71~.Od
package org.flyware.util.page;
K|[p4*6
D>tex/Of3
/** ,5}%_
* @author Joa xVYy`_|
* fNR2(8;}
*/ NMJX `
publicclass Page { w]<V~X
V$wW?+V
/** imply if the page has previous page */ 2OT
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privateboolean hasPrePage; 6L5j
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/** imply if the page has next page */ N,k PR
privateboolean hasNextPage; k*XI/k5Vc
b,C2(?hg
/** the number of every page */ O_=2{k~s0
privateint everyPage; K9-;-{qb
AzFd#P
/** the total page number */ 8(d Hn
privateint totalPage; 0QJ
:
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/** the number of current page */ RHO| g0
privateint currentPage; |T`ZK?B+u
c,@&Z#IZ`
/** the begin index of the records by the current U'4j+vUc
&.W,Hh
query */ >}~\*Y\8@
privateint beginIndex; !fX&i 6
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/** The default constructor */ |!t&ZpdD
public Page(){ >qE f991SZ
q|7i6jq\*R
} zEM c)
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/** construct the page by everyPage b0VEMu81k
* @param everyPage Q[PVkZ
* */ HpLCOY1-
public Page(int everyPage){ 9j94]w2v
this.everyPage = everyPage; -9PJ4"H
} K Eda6zZH
I:|<};mm
/** The whole constructor */ Fw{:fFZC[
public Page(boolean hasPrePage, boolean hasNextPage, h@kq>no
WZ@hP'Zc
I1f4u6\*X
int everyPage, int totalPage, }xx"
int currentPage, int beginIndex){ O$eNG$7
this.hasPrePage = hasPrePage; \_vjc]?
this.hasNextPage = hasNextPage; a7Mn/ i.
this.everyPage = everyPage; "FD`1
this.totalPage = totalPage; \p4>onGI
this.currentPage = currentPage; =Ff _)k
this.beginIndex = beginIndex; ZYS`M?Au
} bm>N~DC
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/** r!+..c
* @return QT8GP?F
* Returns the beginIndex. C4[) yJ
*/ c/6
publicint getBeginIndex(){ ;{L ~|q J
return beginIndex; 8_W=)w6
} 8(3nv[
QG1+*J76b@
/** !l(D0 C
* @param beginIndex ?8U#,qq#`
* The beginIndex to set. s7d4)A%
*/ B3^F
$6=
publicvoid setBeginIndex(int beginIndex){ T0;8koj^_
this.beginIndex = beginIndex; %~e+H|
} )k^y<lC2a
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/** |l-~,eRvi5
* @return 8(zE^W,[8"
* Returns the currentPage. zi^?9n),
*/ !-veL1r
publicint getCurrentPage(){ @D[tljc^
return currentPage; v:F_!Q
} AAXlBY6Y-
fzdWM:g
/** eIDrN%3
* @param currentPage 0:iR=S
* The currentPage to set. mOC<a7#
*/ (- D^_*f
publicvoid setCurrentPage(int currentPage){ F$sDmk#
this.currentPage = currentPage; +^<s'
} c
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/** h}y]Pt?
* @return Zxw
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* Returns the everyPage. @=ro/.
*/ +$YHdgZ.
publicint getEveryPage(){ 7gc?7TM
return everyPage; ZX8AB
} "Cz0r"N
<GWzdj?
/** n\i~H
* @param everyPage pi|=3W
* The everyPage to set. ^`S.Mw.
*/ f6,?Yex8B
publicvoid setEveryPage(int everyPage){ 29HyeLB@
this.everyPage = everyPage; F~$ay@g
} [.Rdq]w6
yU"lJ>Eh}}
/** uXo uN$&
* @return ge4Qa K
* Returns the hasNextPage. @tIY%;Bgk
*/ 2C
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publicboolean getHasNextPage(){ V7"^.W*
return hasNextPage; F{G.dXZZ<
} /UqIkc
4 KX\'K
/** 4aiI&,
* @param hasNextPage tfCK^{
* The hasNextPage to set. (PC)R9r5
*/ 2EH0d6nt
publicvoid setHasNextPage(boolean hasNextPage){ Ya&\ b 6
this.hasNextPage = hasNextPage; ffQm"s:P
} :+_
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/** r3NdE~OAi
* @return "x0/i?pqa
* Returns the hasPrePage. D0}r4eA
*/ kQ`p\}7_
publicboolean getHasPrePage(){ :Vy*MPS5
return hasPrePage; m%cwhH_B
} FL{$9o\@
?J@P0(M#
/** 7Ucq(,\./
* @param hasPrePage &Nw[J5-"k
* The hasPrePage to set. W6s-epsRmT
*/ gW-mXb
publicvoid setHasPrePage(boolean hasPrePage){ /PKu",Azj
this.hasPrePage = hasPrePage; LC4W?']/
} Bm5\*Xd1(
4-?zW
/** ^kK% 8 u
* @return Returns the totalPage. CB0p2WS_
* 8shx7"
*/ B|"-Ed
publicint getTotalPage(){ [pC2#_}
return totalPage; W2&(:C8V@
} \30rF]F`l
N /zP!%L
/** d"tR?j
* @param totalPage l<;~sag
* The totalPage to set. 6 Nws>(Ij
*/ 7]_zWx,r
publicvoid setTotalPage(int totalPage){ }tO>&$
Z6f
this.totalPage = totalPage; )x<BeD
} `B~zB=}
Ig<# {V
} CK#i 6!~r
NX5$x/uz
.^6yCs5~`
:'FCeS9
DP-0,Gt&Xj
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 )b1X6w[
J$U_/b.mk
个PageUtil,负责对Page对象进行构造: \YSprXe
java代码: 1H?I?IT30
w*]FJ-b<.j
#;=sJ[m4
/*Created on 2005-4-14*/ Tol"D2cyf
package org.flyware.util.page; X/_89<&
&xpvHKJl
import org.apache.commons.logging.Log; ,n2"N5{jw
import org.apache.commons.logging.LogFactory; "A> _U<Y
\
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/** G+&pq
* @author Joa e$Mvl=NYp\
* lL&U
ioo}D
*/ s!S_Bt):3
publicclass PageUtil { DYoGtks(
dZo x;_b
privatestaticfinal Log logger = LogFactory.getLog {:|b,ep
T
tXuf !
(PageUtil.class); .Q^V,[on1T
fRT4>So
/** mL-6+pJ@
* Use the origin page to create a new page oQA,57B
* @param page Q/q>mN"#1
* @param totalRecords B}"V.Msv/
* @return <'QI_mP*
*/ )}P/xY0
publicstatic Page createPage(Page page, int M?AKJE j5
qi
">AQpp
totalRecords){ e<qfM&*
return createPage(page.getEveryPage(), Ldj*{t`5
xS:n
page.getCurrentPage(), totalRecords); 0cDP:EzR;
} RL)~J4Y
8rjD1<
/** tyWDa$u,u
* the basic page utils not including exception U^eos;:s8
+* j8[sz
handler ,"F0#5
* @param everyPage =kf"%vFV
* @param currentPage |MOz>1<a
* @param totalRecords ddN G:
* @return page :>/6:c?atG
*/ CYlS8j
publicstatic Page createPage(int everyPage, int [RF]lM]w
*<[zG7+&[
currentPage, int totalRecords){ VkO*+"cGv
everyPage = getEveryPage(everyPage); Abi(1nXdQ
currentPage = getCurrentPage(currentPage); m\XG7uo~
int beginIndex = getBeginIndex(everyPage, hzU(XW
ExMd$`gW
currentPage); B*Ey&DAV
int totalPage = getTotalPage(everyPage, Rt:^'Qi$!
];jp)P2o
totalRecords); O"/Sv'|H#
boolean hasNextPage = hasNextPage(currentPage, )Ay 90Wt
1J72*`4OK
totalPage); ~L>86/hP,N
boolean hasPrePage = hasPrePage(currentPage); 0m=57c$O
n @,.
returnnew Page(hasPrePage, hasNextPage, cRuN;
everyPage, totalPage, m@u%3*:
currentPage, mYj)![
GwfC l{l
beginIndex); ksCF"o/@V
} JypP[yQ
=LODX29
privatestaticint getEveryPage(int everyPage){
I!Z"X&
return everyPage == 0 ? 10 : everyPage; i(OeE"YA
} V#5$J Xp
2Y<]X7Ch:
privatestaticint getCurrentPage(int currentPage){ FE]UqB
return currentPage == 0 ? 1 : currentPage; )0]U"Nf ho
} ,QpFVlPU
YaL:6[6
privatestaticint getBeginIndex(int everyPage, int OScqf]H
s2GF*{
currentPage){ (KwC,0p
return(currentPage - 1) * everyPage; c/ih%xR
} .c:h!-D;
(Zd(?">i
privatestaticint getTotalPage(int everyPage, int FUlhEH
.Zj`_5C
totalRecords){ C\aHr!
int totalPage = 0; vf$IF|
+iFt)
if(totalRecords % everyPage == 0) n>R(e>
totalPage = totalRecords / everyPage; cs?WE9N
else 1_#;+S
totalPage = totalRecords / everyPage + 1 ; E1tCY.N{
dq`{fqGl
return totalPage; 8e3eQ
} K!.t}s.t
q*|Alrm
privatestaticboolean hasPrePage(int currentPage){ EFljUT?&
return currentPage == 1 ? false : true; Kvo&_:
} 1^2Q`~,g
<nN.$4~X
privatestaticboolean hasNextPage(int currentPage, 5OtdB'UITd
oC*a;o
int totalPage){ 1kw*Q:
return currentPage == totalPage || totalPage == )dqNN tS
mJ=V<_
0 ? false : true; \wk;Bo
} =JgR c7
xVbRCu#Z
1:<(Q2X%
} rhy-o?
} `r.fD
5lJL[{
86N,04
fZ5 UFq_~s
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。 k&%i+5X
IsE3-X|
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 kY'Wf`y(
*d;TpwUI
做法如下: vdAd@Z~\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Z\EA!Cs3
8cG`We8l&
的信息,和一个结果集List: q(:L8nKT]
java代码: \U]K!K=
1(dKb
aEvbGo
/*Created on 2005-6-13*/ )LIn1o_,
package com.adt.bo; X,_K
)f
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import java.util.List; %" 7UYLX
}O
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import org.flyware.util.page.Page; y|KQ`;
h=gtuaR4
/** 8K-P]]
* @author Joa k]5tU\;Yw
*/ $b1>,d'oz
publicclass Result { S-88m/"]s
qbfX(`nS
private Page page; mV`R'*1UC
H"8B4~*7H
private List content; tEvDAI} 5
7~XA92
/** vm_]X{80;
* The default constructor W/xPVmnV
*/ S-q"'5>
public Result(){ t#|R"Q#
super(); CvE^t#Bok
} *c[w9(fU
R$hIgw+p[
/** ~M{/cv
* The constructor using fields ; Z7!BU
* h7q{i|5
* @param page 5rB>)p05[
* @param content 4RB%r
*/ gM>?w{!LBx
public Result(Page page, List content){ '~K]=JP
this.page = page; KFHZ3HZ:>
this.content = content; T=tW'tlT\v
} eG!ma` v
^AaE$G&:
/** *)-@'{]u B
* @return Returns the content. 452kE@=49
*/ LdG? kbJ&y
publicList getContent(){ \WFcb\..
return content; XZARy:+bc
} bRy(`
q%])dZ!lE
/** #<b\B qYG
* @return Returns the page. 5)T[ha77u
*/ [;Lgbgt3f
public Page getPage(){ V&:x+swt
return page; /qy6YF8;y
} m\XsU?SuX
ygIn6.p
/** .ZF%$H
* @param content \{:A&X~\!
* The content to set. jDb\4QyC
*/ 7WS$fUBi
public void setContent(List content){ v{t
pRL0
this.content = content; h>D;QY
} trwQ@7
EA>.SSs!
/** #0b:5.vy
* @param page X/2GTU7?
* The page to set. <hCO-r#
*/ n]$rLm%^
publicvoid setPage(Page page){ f;BY%$
this.page = page; D1Zy Js#
} }i"[5:
} GJcxqgk$
4z(B`t~7
xRacgny:I
\z.bORy
?SFQx\/
2. 编写业务逻辑接口,并实现它(UserManager, j
[lS.Lb
06^/zr
UserManagerImpl) .(q'7Q Z/
java代码: dV38-IfGkl
"[?DS
AJEbiP
/*Created on 2005-7-15*/ Z3{1`"\<K
package com.adt.service; XJeWhk3R9
R&.&x'<
import net.sf.hibernate.HibernateException; 0}NDi|o
hxMRmH[f:
import org.flyware.util.page.Page; Y,0Z&6 <
2H.g!( Oza
import com.adt.bo.Result; /}~=)QHH
4E 5;wH
/** M{G}-QK_.
* @author Joa ;X<Ez5v3
*/ gjG SI'M0B
publicinterface UserManager { $3 -QM
Any y
public Result listUser(Page page)throws ca7Y+9<
;
EQ~<NzRp=
HibernateException; GD.Ss9_h1
}Mt)57rU
} 0)d='3S
_LwF:19Il
Ez|NQ:o
3JQ7Cc>
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java代码: P'tXG
\DujF>:
UU>+ b:
/*Created on 2005-7-15*/ H%Gz"
package com.adt.service.impl; Qf^c}!I
tcXXo&ZS
import java.util.List; MF< ZB_@
]?1_.Wjtt
import net.sf.hibernate.HibernateException; VBi gUK4
K9Mz4K_
import org.flyware.util.page.Page; 2YZ>nqy
import org.flyware.util.page.PageUtil; .c}+kHv
hJ`Gu7
import com.adt.bo.Result; q-;Y }q
import com.adt.dao.UserDAO; Og% Y._
import com.adt.exception.ObjectNotFoundException; &j1-Ouy
import com.adt.service.UserManager; J1I,;WGf
zJy=1r
/** YdO*5Gb6
* @author Joa tWy.Gz\
*/ pt.V^a
publicclass UserManagerImpl implements UserManager { xAd@.^
J/e]
private UserDAO userDAO; i \NV<I
1xS+r)_n@
/** =AzPAN#e
* @param userDAO The userDAO to set. H;\C7w|
*/ q,)V0Ffe[|
publicvoid setUserDAO(UserDAO userDAO){ V5ZC2H
this.userDAO = userDAO; @6~lZgXOV[
} [A =0fg5
wX}p6yyN
/* (non-Javadoc) \:{K",2
* @see com.adt.service.UserManager#listUser HBe*wk Pd
Sk+XBX(}
(org.flyware.util.page.Page) axUj3J>
*/ <9X@\uvU.<
public Result listUser(Page page)throws yR|2><A
Nf!N;Cy?
HibernateException, ObjectNotFoundException { iS+"Jsz
int totalRecords = userDAO.getUserCount(); .kFO@:
if(totalRecords == 0) }ZVond$y4
throw new ObjectNotFoundException b)'CP Cu*
FulFEnSV
("userNotExist"); A{q%sp:3~
page = PageUtil.createPage(page, totalRecords); ,on]Fts
List users = userDAO.getUserByPage(page); !0?o3,of-
returnnew Result(page, users); ^7+;XUyg
} fdKE1,;
l,h`YIy
} W>a}g[Ad
YRVh[Bqg`
qI7KWUR
+^(_S9CO
RD[P|4eY
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 &J2UAmB
s9sl*1n1m`
询,接下来编写UserDAO的代码: 0yC~"u[N Y
3. UserDAO 和 UserDAOImpl: 8WQ#)
java代码: #[9UCX^=
lfDd%.:q4S
_1E c54D
/*Created on 2005-7-15*/ gNP1UH4m
package com.adt.dao; Z(|$[GZP[
8%B_nVc
import java.util.List; bgBvzV&'8
QD!NV*
import org.flyware.util.page.Page; 9dA+#;?
<rgK}&q
import net.sf.hibernate.HibernateException;
p*lP9[7
\u`P(fI!K%
/** 69r%b7#
* @author Joa =5Db^
*/ ~_JfI7={Jn
publicinterface UserDAO extends BaseDAO { PI%l
9k71h`5
publicList getUserByName(String name)throws `{{6vb^g
UZs '[pm)
HibernateException; Jkj7ty.J
kl:/PM^
publicint getUserCount()throws HibernateException; Ywhhs
}f
qX\85dPn@}
publicList getUserByPage(Page page)throws VC/n}7p
*Lrrl
HibernateException; 4dFr~ {
79>x/jZka
} 7I w^
5PeYQ-B|
w~Q\:<x&~Z
Sc{&h8KMTb
DDkN3\w
java代码: 1(Vv-bq$
</_QldL_
,H6P%
/*Created on 2005-7-15*/ j%`
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package com.adt.dao.impl; H.l0kBeG
Q +l{> sL
import java.util.List; (v?@evQ
xL_QTj
import org.flyware.util.page.Page; %TN$
N~/X.D4e#
import net.sf.hibernate.HibernateException; E8kD#tL
import net.sf.hibernate.Query; S>x@9$( ym
"vybVWEE
import com.adt.dao.UserDAO; &M@ .d$<C
'L O3[G{
/** -S]ercar
* @author Joa 16Ka>=G
*/ Fu{VO~w
public class UserDAOImpl extends BaseDAOHibernateImpl geK;r0(f
!%R):^R8
implements UserDAO { -x6_HibbD
[x7Rq_^
/* (non-Javadoc) gnN>Rl
5_
* @see com.adt.dao.UserDAO#getUserByName hb*Y-$Zp
Cu%BU}(
(java.lang.String) 4qDO(YWf
*/ _$T
!><)y
publicList getUserByName(String name)throws qfT9g>EF
c}OveR$'&
HibernateException { +$ djX=3
String querySentence = "FROM user in class YC%xW*
31^/9lb
com.adt.po.User WHERE user.name=:name"; X_X7fRC0
Query query = getSession().createQuery gHp4q!SJ7
yx?oxDJg
(querySentence); STu(I\9
query.setParameter("name", name); JzywSQ
return query.list(); wE1 GyN
} />Zfx. Aj6
C&0f8PnD
/* (non-Javadoc) FYik}wH]
* @see com.adt.dao.UserDAO#getUserCount() >yn?@ve@
*/ )2" g)9!
publicint getUserCount()throws HibernateException { $9\8?gS
int count = 0; HHw&BN