Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 2Z6#3~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 lhTjG,U=
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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 FG7}MUu
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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 ]]$s"F<
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分页支持类: U9IP`)z_5t
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java代码: W-%oj.BMA
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package com.javaeye.common.util; %'j)~
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import java.util.List; JwbC3t):@
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publicclass PaginationSupport { |@={:gRJ{x
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publicfinalstaticint PAGESIZE = 30; >z6(fM`i
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privateint pageSize = PAGESIZE; {zBf *x
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privateList items; p~I+ZYWF'
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privateint totalCount; 7X.rGJZq
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privateint[] indexes = newint[0]; 9@Yk8
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privateint startIndex = 0; ^AMcZ6!\
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public PaginationSupport(List items, int _*6nTSL
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totalCount){ }% JLwN
setPageSize(PAGESIZE); +T=Z!2L
setTotalCount(totalCount); q2 D2:0^ 2
setItems(items); @HJ&"72$<
setStartIndex(0); =6imrRaaV
} $ x
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public PaginationSupport(List items, int /j./
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totalCount, int startIndex){ T5NO}bz
setPageSize(PAGESIZE); Z5;1ySn{
setTotalCount(totalCount); $6h:j#{JE
setItems(items); =C8 t5BZ"
setStartIndex(startIndex); M*BDrM
} 7+JQaYO`"
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public PaginationSupport(List items, int 2V_C_5)1
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totalCount, int pageSize, int startIndex){ 8I04Nx
setPageSize(pageSize); oAe]/ j$
setTotalCount(totalCount); ]K0<DO9
setItems(items); UA/Q3)
setStartIndex(startIndex); V0z.w:-
} G>&=rmK"
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publicList getItems(){ k_#ra7zP
return items; fLL_{o0T
} {<iIL3\mC
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publicvoid setItems(List items){ ^kxkP}[Z.
this.items = items; $'dJ+@
} :\L{S
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publicint getPageSize(){ +4f>njARIb
return pageSize; Bvzl*
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} *qYcb}
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publicvoid setPageSize(int pageSize){ V"(S<o
this.pageSize = pageSize; $q]((@i.
} {MU>5\
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publicint getTotalCount(){ 9r@r\-
return totalCount; :pcKww|V
} /E$"\md
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publicvoid setTotalCount(int totalCount){ -X5rGp++
if(totalCount > 0){ dG}fpQ3&
this.totalCount = totalCount; X{\>TOk
int count = totalCount / OEy'8O$
lBh|+KN
pageSize; vC[)/w
if(totalCount % pageSize > 0) S9}P5;u
count++; g4!zH};n
indexes = newint[count]; _,_>B8
for(int i = 0; i < count; i++){ o0&jel1a
indexes = pageSize * "2(lgxhj
ym:^Y-^iV
i; k1i*1Tc
} pbKDtqSnz
}else{ Teu4 ;
this.totalCount = 0; |[(4h
} =\`g<0
} YuSe~~F)j
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publicint[] getIndexes(){ zz 7m\
return indexes; Kc_QxON4
} YOwo\'|=
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publicvoid setIndexes(int[] indexes){ n^'ip{
this.indexes = indexes; .5|AX6p+^
} tKrr5SRb
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publicint getStartIndex(){ ]Gm,sp.x
return startIndex; }"wWSPD
} B5*{85p(u
}MW*xtGV
publicvoid setStartIndex(int startIndex){ [tym~ZZ]_m
if(totalCount <= 0) OJ\IdUZ
this.startIndex = 0; J!O5`k*.C
elseif(startIndex >= totalCount) /vS!9f${
this.startIndex = indexes YW9 [^
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[indexes.length - 1]; Xg?hh 0s
elseif(startIndex < 0) S9J<3
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this.startIndex = 0; k-xh-&
else{ RoSh|$JF
this.startIndex = indexes o1YX^-<[F
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[startIndex / pageSize]; j0^~="p%C
} n(l!T
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} |4aV~n[>#
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publicint getNextIndex(){ Q
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int nextIndex = getStartIndex() + SdBv?`u|g
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pageSize; [
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if(nextIndex >= totalCount) EWNh:<F?
return getStartIndex(); zm)
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else db$Th=s[
return nextIndex; zvYkWaa_Qz
} )dgXS//Y
A-1Wn^,>*
publicint getPreviousIndex(){ =z'- B~
int previousIndex = getStartIndex() - _HX1E
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pageSize; vt<r_&+ pJ
if(previousIndex < 0) UhYeyT
return0; 5:/
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else I!&|L0Qq
return previousIndex; )9MmL-7K
} T^g2N`w2
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} >(S4h}^I
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抽象业务类 u@5vK2
java代码: /:d03N\9k
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/** ewg&DBbN"
* Created on 2005-7-12 Gf\Dc
*/ L22GOa0
package com.javaeye.common.business; H|k!5W^
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import java.io.Serializable; vJVL%,7
import java.util.List; @y3w_;P
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import org.hibernate.Criteria; _"
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import org.hibernate.HibernateException; 8-5MGh0L
import org.hibernate.Session; MO&QR-OY
import org.hibernate.criterion.DetachedCriteria; e}y oy+9
import org.hibernate.criterion.Projections; r,X5@/
import z=:<]j#=
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org.springframework.orm.hibernate3.HibernateCallback; *#-X0}'s
import DKgwi'R
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org.springframework.orm.hibernate3.support.HibernateDaoS m6tbN/EJZ
By(:%=.
upport; a5ZU"6Hi
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import com.javaeye.common.util.PaginationSupport; S453oG"
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public abstract class AbstractManager extends &cztUM(
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HibernateDaoSupport { QEK,mc3
{Ak{
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privateboolean cacheQueries = false; t=syo->
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privateString queryCacheRegion; H_KE^1
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publicvoid setCacheQueries(boolean QLrFAV
Wc [@,
cacheQueries){ 4of3#M
this.cacheQueries = cacheQueries; Ac;rMwXk#
} qOYCQ
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publicvoid setQueryCacheRegion(String vKN"o* q
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queryCacheRegion){ O9*cV3}H
this.queryCacheRegion = ss63/
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queryCacheRegion; h1@|UxaE#
} }[XzM/t
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publicvoid save(finalObject entity){ .WM 0x{t/
getHibernateTemplate().save(entity); w^MU$ubx
} }MAQhXI^O|
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publicvoid persist(finalObject entity){ B5h-JON]-
getHibernateTemplate().save(entity); ^(y=DJ7
} wJ@8-H 8}
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publicvoid update(finalObject entity){ S6CM/
getHibernateTemplate().update(entity); #TZf\0\!
} 9XWHr/-_@
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publicvoid delete(finalObject entity){ !]1X0wo\
getHibernateTemplate().delete(entity); k_%2Ok
} b);Pw"_2
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publicObject load(finalClass entity, +;~JHx.~X
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finalSerializable id){ sPY*2B
return getHibernateTemplate().load ofbNg_K>
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(entity, id); %}jwuNGA
} V&`\ s5Q
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publicObject get(finalClass entity, 54~`8f
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finalSerializable id){ ?hUC#{
return getHibernateTemplate().get 4GWt.+{J$
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(entity, id); amq]&.M
} |S48xsFvq
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publicList findAll(finalClass entity){ ,ButNBv
return getHibernateTemplate().find("from `$oGgz6ZT
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" + entity.getName()); RG/M-
} h-
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publicList findByNamedQuery(finalString bOjvrg;Sz\
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namedQuery){
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return getHibernateTemplate UwOZBF<
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().findByNamedQuery(namedQuery); =H6"\`W
} vaL+@Kq~&
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publicList findByNamedQuery(finalString query, tiG=KHK%o
*A C){M
finalObject parameter){ 'Lu7cb^
return getHibernateTemplate <>/0;J1<
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().findByNamedQuery(query, parameter); K +n
} 4cJ7W_ >i6
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publicList findByNamedQuery(finalString query, ?B
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finalObject[] parameters){ y<mmv~=
return getHibernateTemplate $;NxO0$
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().findByNamedQuery(query, parameters); ;okFm
} ~]f+
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publicList find(finalString query){ j`jF{k b
return getHibernateTemplate().find !4-B
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(query); z%cq%P8g
} N,U<.{T=A
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publicList find(finalString query, finalObject
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parameter){ ; (I(TG
return getHibernateTemplate().find Ut:>'TwG
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(query, parameter); D?;8bI%"
} 2)}ic2]pn
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public PaginationSupport findPageByCriteria P 1`X<A
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(final DetachedCriteria detachedCriteria){ \|
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return findPageByCriteria \49LgN@\
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 2qV.`d
} &K2J$(.t
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public PaginationSupport findPageByCriteria 6 ,jp-`
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(final DetachedCriteria detachedCriteria, finalint Zp'c>ty=
[ ySO
startIndex){ N&g9z{m7
return findPageByCriteria 9x;CJhX
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(detachedCriteria, PaginationSupport.PAGESIZE, EfA*w/y
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startIndex); <Stfqa6FJ
} dIk/vg
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public PaginationSupport findPageByCriteria ~=HrD?-99p
1 .\|,$
(final DetachedCriteria detachedCriteria, finalint 3S4'x4*
<P&~k\BuF{
pageSize, H9nVtS{x
finalint startIndex){ 9W{`$30
return(PaginationSupport) !Ld0c4
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getHibernateTemplate().execute(new HibernateCallback(){ Vk%[N>
publicObject doInHibernate I|jGu9G
q{D_p[q
(Session session)throws HibernateException { b0W~*s [4
Criteria criteria = )Los\6PRn
/)I:Cz/f
detachedCriteria.getExecutableCriteria(session); CZ2&9Vb9I
int totalCount = S!!i
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((Integer) criteria.setProjection(Projections.rowCount |eS5~0<`
AITV+=sN
()).uniqueResult()).intValue(); PDN3=PAR/A
criteria.setProjection 'iy &%?
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(null); 4wp5ghe
List items = vLQ!kB^\W
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criteria.setFirstResult(startIndex).setMaxResults b[+G+V
^7Sk`V
(pageSize).list(); [k~V77w
14
PaginationSupport ps = 4`Com~`6"
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new PaginationSupport(items, totalCount, pageSize, *n9t~t6GHg
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startIndex); 6ww4ZH?j
return ps; k.Tu#7
} P%#WeQ+
}, true); Yphru"\$
} aXi5~,Ks_
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public List findAllByCriteria(final s^5KFK1
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DetachedCriteria detachedCriteria){ IIC1T{D}v
return(List) getHibernateTemplate /8V#6d_
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().execute(new HibernateCallback(){ :e9}k5kdk
publicObject doInHibernate fq^D<c{3
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(Session session)throws HibernateException { &?~OV:r9
Criteria criteria = 3SbtN3
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detachedCriteria.getExecutableCriteria(session);
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return criteria.list(); QwaCaYoh
} dWR0tS6vR`
}, true); ,E&PIbDL1
} P'Q|0lB
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public int getCountByCriteria(final `-)!4oJ]
l=(4o4um
DetachedCriteria detachedCriteria){ y+3<
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Integer count = (Integer) u= a5Z4 N'
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getHibernateTemplate().execute(new HibernateCallback(){ fiDwa
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publicObject doInHibernate WzM9{c
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(Session session)throws HibernateException { .xXe *dm%
Criteria criteria = }9n{E-bj *
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detachedCriteria.getExecutableCriteria(session); wNsAVUjLe
return L2"fO
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criteria.setProjection(Projections.rowCount :',.I
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()).uniqueResult(); *=]hc@
} 6"+/Imb-
}, true); |\g =ua+h
return count.intValue(); T&.ZeB1
} \^<eJfD
} eow6{CD8
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用户在web层构造查询条件detachedCriteria,和可选的 j$l[OZ:#
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 >Mml+4<5
fhx_v^<X
PaginationSupport的实例ps。 HKA7|z9{
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ps.getItems()得到已分页好的结果集 F :"CaDk
ps.getIndexes()得到分页索引的数组 YE<_a;yh1
ps.getTotalCount()得到总结果数 V!!E)I
ps.getStartIndex()当前分页索引 J}?F4
ps.getNextIndex()下一页索引 *P4G}9B|9:
ps.getPreviousIndex()上一页索引 I@dS/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 g'G"`)~ 2
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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 FJ}RT*7_C
sQt]Y&_/@
一下代码重构了。 b&k !DeE
&A=>x
我把原本我的做法也提供出来供大家讨论吧: jYAD9v%
KiXXlaOs
首先,为了实现分页查询,我封装了一个Page类: ElNKCj<M
java代码: ^l\U6$3
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/*Created on 2005-4-14*/ )bc0 t]Fs
package org.flyware.util.page; H]@M00C
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/** 3OUZR5_$
* @author Joa xL,;(F\^
* n[Jpy[4g
*/ 98u$5=Z'/
publicclass Page { OhT?W[4
n[# !Q`D
/** imply if the page has previous page */ \iFh-?(
privateboolean hasPrePage; D[)
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2BA'Zu`
/** imply if the page has next page */ {Lj]++`fB]
privateboolean hasNextPage; k@1\ULo
NFT&\6!o
/** the number of every page */
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privateint everyPage; \(9hg.E
|KR;$e&
/** the total page number */ 8,0p14I5;
privateint totalPage; (8C
,"Dc[0
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/** the number of current page */ I_"1.
privateint currentPage; w4YuijhW
9Xw(|22
/** the begin index of the records by the current "F/% {0d
BLzlXhHn
query */ Bob K>db
privateint beginIndex; U8_<?Hd
mfHZGk[[
3DH}
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/** The default constructor */ Q[t|+RNKv2
public Page(){ Bny3j~*U
ZTV|rzE
} ,k}-I65M*t
{[V<mT2/
/** construct the page by everyPage /]~Oa#SQ:
* @param everyPage 0zD[mt
* */ RY=B>398:
public Page(int everyPage){ G]Fp},
this.everyPage = everyPage; $RxS<_tj
} &6-udZB-
@ i$jyc
/** The whole constructor */ ;eYm+e^?.
public Page(boolean hasPrePage, boolean hasNextPage, 29R_?HBH
V gLnpPOQ
#.|efdsG
int everyPage, int totalPage, m22FOjk\
int currentPage, int beginIndex){ FsI51@V72Q
this.hasPrePage = hasPrePage; QkJAjmB
this.hasNextPage = hasNextPage; fi*@m,-
this.everyPage = everyPage; nCF1i2*6|"
this.totalPage = totalPage; LadE4:oy
this.currentPage = currentPage; df}DJB
this.beginIndex = beginIndex; nH*JR
} z;? 32K
#*QnO\.
/** rPf<8oH
* @return 9ohaU
* Returns the beginIndex. ]"Y?
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*/ G:'hT=8
publicint getBeginIndex(){ xVOoYr>O
return beginIndex; fUy:TCS
} SJ(<u2J]
K0hmRR=
/** WP/?(%#Y
* @param beginIndex eEvE3=,hg
* The beginIndex to set. y\M]\^[7
*/ #bN'N@|
publicvoid setBeginIndex(int beginIndex){ '!8'Xo@Go3
this.beginIndex = beginIndex; L1'R6W~%dN
} M`6rI
6_`9
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/** QDO.&G2
* @return 9F[k;Uw
* Returns the currentPage. ^Ec);Z
*/ bb@@QzR
publicint getCurrentPage(){ t=
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return currentPage; `ceetr=
} D?yiK=:08`
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/** aj>6q=R
* @param currentPage d|T87K>|r"
* The currentPage to set. -:mT8'.F-
*/ 'Em5AA`>
publicvoid setCurrentPage(int currentPage){ /CRZ
this.currentPage = currentPage; RM/q\100
} AUZ^XiK
ma__LWKM,
/** VJp; XM
* @return ;- ~}g 7$
* Returns the everyPage. Fp3NWvu
*/ (-'Jf#&X^
publicint getEveryPage(){ <kJ,E[4`
return everyPage; PNNY_t +I
} :xd)]Ns
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/** ;8!L*uMI
* @param everyPage (yh zjN~
* The everyPage to set. g9N_s,3jC
*/ -M{.KqyW
publicvoid setEveryPage(int everyPage){ ){~]-VK
this.everyPage = everyPage; ?]1_ 2\M
} (e,5
b
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/** E'_3U5U
* @return ?<mxv"
* Returns the hasNextPage. }q-* Ls~
*/ =8Bq2.nlR
publicboolean getHasNextPage(){ Szz:$!t
return hasNextPage; <$ H-/~Y
} X,+M?
HN7C+e4U~
/** X:3W9`s)*
* @param hasNextPage s2`:NS
* The hasNextPage to set. 9d5|rk8VS
*/ ;gE]*Y.Z.p
publicvoid setHasNextPage(boolean hasNextPage){ ak_&\'P
this.hasNextPage = hasNextPage; S.^/Cl;aj
} rV
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'WF Ey>1#
/** _VvXE572
* @return 0m`{m'B4n
* Returns the hasPrePage. =Fu~ 0Wc
*/ m+Um^:\jX
publicboolean getHasPrePage(){ {`X O3
return hasPrePage; .(2Zoa
} VMa\?`fT
iLvzoQ
/** (fSpY\JPI
* @param hasPrePage -UTTJnu^
* The hasPrePage to set. h_xHQf
*/ xna4W|-
publicvoid setHasPrePage(boolean hasPrePage){ yu^n;gWH
this.hasPrePage = hasPrePage; "2J$~2{N
} Hi V7
qj$6/V|D
/** 3Gr:.V9=
* @return Returns the totalPage. *=b#>//
* Py}] {?
*/ f`^\v
publicint getTotalPage(){ e\ Igc.
return totalPage; LBCat=d<
} *_Sx^`"X`l
Z+3j>_Ss
/** vv 7T/C
* @param totalPage "q<}#] u
* The totalPage to set. VZo,AP~
*/ U/p|X)
publicvoid setTotalPage(int totalPage){ ke~S[bL%-
this.totalPage = totalPage; # Vq"Cf
} o?T01t=
z8n=\xL
} A7eF.V&
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Ei$@)qS/
*|OP>N
/kK%}L_D
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 3$~6+i
C VyYV &U,
个PageUtil,负责对Page对象进行构造: C;DR@'+q
java代码: s]lIDp}
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x{|`q9V~ N
/*Created on 2005-4-14*/ Hea76P5$P+
package org.flyware.util.page; ug?])nO.C
z[E gMS!
import org.apache.commons.logging.Log; . #7B10
import org.apache.commons.logging.LogFactory; Y<h [5
[UW%(N
/** AJ%x"
* @author Joa E <O:
* S|_} 0
*/ #0F6{&;
M
publicclass PageUtil { 6`V2-zv$
3Mlwq'pzD
privatestaticfinal Log logger = LogFactory.getLog +CQ$-3
7?[{/`k~?
(PageUtil.class); o5;V=8T;
[Y%H8}
/** @a[Y[FS
* Use the origin page to create a new page .5ItH^
* @param page s{30#^1R
* @param totalRecords S1`;2mAf*
* @return 2)W~7GED
*/ *!W<yNrR
publicstatic Page createPage(Page page, int Gs0x;91
'IykIf
totalRecords){ p%?VW
return createPage(page.getEveryPage(), /&T"w,D
ophQdJM
page.getCurrentPage(), totalRecords); gPA),
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} rNl`w.
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/** p1mY@[A
* the basic page utils not including exception @ff83Bg
vT&xM
handler 5Vj t!%?r
* @param everyPage X-mhz3Q&a
* @param currentPage piy_9nk
* @param totalRecords ;FI"N@z
* @return page kCuIEv@
*/ LY? `+/
publicstatic Page createPage(int everyPage, int H:x{qS4Si
ivi,/~L
currentPage, int totalRecords){ X
/
{;
everyPage = getEveryPage(everyPage); LYV\|a{Y
currentPage = getCurrentPage(currentPage); 1~|o@CO
int beginIndex = getBeginIndex(everyPage, 8}A+{xVp8
J8>8@m6
currentPage); :RqTbE4B
int totalPage = getTotalPage(everyPage, 3u tJlD
xi!CZNz
totalRecords); 7YLG<G!v)]
boolean hasNextPage = hasNextPage(currentPage, <q dM
{dk%j~w8
totalPage); I8%2tLVY
boolean hasPrePage = hasPrePage(currentPage); bt2`elH|
zdh&,!] F6
returnnew Page(hasPrePage, hasNextPage, _rmTX.'w
everyPage, totalPage, mh8{`W &
currentPage, $v#\bqY
VEtdp*ot
beginIndex); MD62ObK!
} =;!$Qw4
jJ B+UF=
privatestaticint getEveryPage(int everyPage){ =MP?aH
[
return everyPage == 0 ? 10 : everyPage; "'8^OZR
} o/6'g)r*
hh$V[/iK
privatestaticint getCurrentPage(int currentPage){ M|l`2Hpe
return currentPage == 0 ? 1 : currentPage; > 0kZ-M5
} q7!$-
*$4 EXwt'
privatestaticint getBeginIndex(int everyPage, int GCEcg&s=\S
o2J-&
currentPage){ a7_ &;
return(currentPage - 1) * everyPage; ZtFOIb*
} RdtF5#\z
;rK=
jz^Q
privatestaticint getTotalPage(int everyPage, int UF$JVb
~Ip-@c}'j
totalRecords){ l^ Q-KUI
int totalPage = 0; (C=.&',P
ohod)8
if(totalRecords % everyPage == 0) , (Bo .(]
totalPage = totalRecords / everyPage; c-dOb.v0
else i- v PJg1
totalPage = totalRecords / everyPage + 1 ; %( tu<
@+,J^[ y
return totalPage; h>A~..
} 5Lo\[K>j
X`n)]~
privatestaticboolean hasPrePage(int currentPage){ v"po}K
return currentPage == 1 ? false : true; $XOs(>~"r
} y7?n;3U]CS
ioZ{2kK
privatestaticboolean hasNextPage(int currentPage, YKk*QcAn
VPAi[<FzOG
int totalPage){ eMDO;q
return currentPage == totalPage || totalPage == 5ml#/kE
YaWZOuxm
0 ? false : true; bIR&e E
} +5>*$L%8T`
1%R8q=_
n&4 4Acs[
} oQ=v:P]
lO=Nw+'$S
`ecIy_O3P&
2D"n#O`y
)e1&[0
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。 bJ$6[H-:
oXQzCjX_
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 R'#1|eWCa
cU+%zk
做法如下: iFypKpHg~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \bc ob8u
bGO[P<<
的信息,和一个结果集List: 6BnP"R.
java代码: ry2ZVIFa
|6ZH+6[
N3Yf3rK
/*Created on 2005-6-13*/ [X"F}ph
package com.adt.bo; feI%QnK)U
TH%J=1d
import java.util.List; 3.c0PRZ
Bc^%1
import org.flyware.util.page.Page; wd
4]Z0;
s\CZ os&
/** a___SYl
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* @author Joa \fk%^1XY
*/ 91Fx0(
publicclass Result { a
(mgz&*
!P_8D*^9
private Page page; _yu d
sghQ!ux
private List content; 3\ !DsPgW
C'_^DPzj
/** V\!6K
* The default constructor s5
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*/ .:`+4n
public Result(){ 7;wx,7CUq
super(); !ULU#2'1
} eLvbPE_
)37 .H^7
/** ['*{f(AI
* The constructor using fields I"4Lma
* f4h|Nn%;
* @param page r&MHww1i
* @param content hJ>Kfm
*/ p H5iv>H
public Result(Page page, List content){ |3a1hCxt
this.page = page; Dm")\"5\?
this.content = content; _N-.=86*
} &{x%"Aq/
T[z}^"
/** g?}$"=B
* @return Returns the content. l$1z%|I
*/ !'
D1aea5
publicList getContent(){ oC~8h8"l
return content; |2YkZ nJn
} sM4Qu./
~"Kf+eFi
/** #lf3$Tm D
* @return Returns the page. w6PKr^
*/ J#```cB
public Page getPage(){ 5)T=^"IHXi
return page; |9Gng`)
} &V$qIvN$
o/;kzi
/** w`N|e0G@
* @param content BotGPk><c
* The content to set. ~=!d>f~U
*/ "M GX(SQ
public void setContent(List content){ sW53g$`v
this.content = content; H(JgqbFB*
} &gNb+z+
n O^m
/** R.Plfm06Ue
* @param page Nx%]dOa
* The page to set. FE0}V}\=h
*/ e]1&f.K
publicvoid setPage(Page page){ z<T(afM{*
this.page = page; <;O-N=
} 9i&(VzY[=
} HB>&}z0
udEJo~u
wc&`/'<p
rzR=% >
C9,|G7~*q
2. 编写业务逻辑接口,并实现它(UserManager, J$]-)`[G&
xbN)z
UserManagerImpl) ]\qbe
java代码: Eeumi#$Z
2/T4.[`t
k^JV37;bl
/*Created on 2005-7-15*/ c]eDTbXd
package com.adt.service; {.D^2mj|
zq:+e5YT?T
import net.sf.hibernate.HibernateException; 0ESxsba
e%Sw(=a
import org.flyware.util.page.Page; 4(h19-V
?yfw3s
import com.adt.bo.Result; \),DW)
t#fbagTON
/** 17\5NgB
* @author Joa xrXfLujn%
*/ I3ZlKI
publicinterface UserManager { %![%wI?
N=JZtf/i
public Result listUser(Page page)throws Ih&rXQ$
pG|+\k/B
HibernateException; *2?-6
CTNeh%K;
}
dGNg[
2"'<Yk9
E1=WH-iA0
xw>\6VNt
oHW:s96e
java代码: FLb
Q#c\
~]d3
f
||}k99y +
/*Created on 2005-7-15*/ 3pV^Oe^9
package com.adt.service.impl; o_(@v2G`
O/?Lk*r
import java.util.List; +9tm9<F8
&=KNKE`
import net.sf.hibernate.HibernateException; Hv>16W$_
*-zOQ=Y
import org.flyware.util.page.Page; &|d6
import org.flyware.util.page.PageUtil; <kmH^viX
(= T%eJ61
import com.adt.bo.Result; ytWTJ>L
import com.adt.dao.UserDAO; M6j!_0j
import com.adt.exception.ObjectNotFoundException; #835$vOe
import com.adt.service.UserManager; 37F&s
%u)niY-g
/** cnm*&1EzV
* @author Joa Y]9AC
*/ e
hgUp =
publicclass UserManagerImpl implements UserManager { Fm| h3.`V
q
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private UserDAO userDAO; VJ8"Q
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/** "1-gMob
* @param userDAO The userDAO to set. (]Pr[xB
*/ ++m^z` D
publicvoid setUserDAO(UserDAO userDAO){ lCX*Q{s22
this.userDAO = userDAO; )zKZ<;#y
} HW@r1[Y
)Rlh[Y& r
/* (non-Javadoc) 1 m>x5Dbk!
* @see com.adt.service.UserManager#listUser 68!W~%?pR
&4dh $w]q
(org.flyware.util.page.Page) 'Avp16zg
*/ 1luRTI8^
public Result listUser(Page page)throws }Qqi013E L
&>YdX$8x
HibernateException, ObjectNotFoundException { ;PA^.RB
int totalRecords = userDAO.getUserCount(); [yEH!7
if(totalRecords == 0) C{5bG=Sg~
throw new ObjectNotFoundException M%vZcP
@[s+5_9nk
("userNotExist"); Yp;6.\Z8[
page = PageUtil.createPage(page, totalRecords); k*U(ln
List users = userDAO.getUserByPage(page); ,drcJ
returnnew Result(page, users); tn\PxT
} KysJ3G.k\
C<T)'^7z
} w.:fl4V
=Qf.
RyN}Gz/YN
$Y\-X<gRH
Y\e8oIYu7
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q!T+Jc9N
&|LP>'H;
询,接下来编写UserDAO的代码: v5/2-<6x
3. UserDAO 和 UserDAOImpl: "Q[rM1R
java代码: KiaQ^[/q
Wifr%&t{J
2H]~X9,z2
/*Created on 2005-7-15*/ hE9UWa.Q>
package com.adt.dao; QrX 5Kwq
({5`C dVi
import java.util.List; `El)uTnuZ[
T+q3]&
import org.flyware.util.page.Page; @j{n
V@|
i:@n6GW+iw
import net.sf.hibernate.HibernateException; "h84D&V
G(*7hs
/** |_H{B+.
* @author Joa O^_$cq
*/ fPj*qi
publicinterface UserDAO extends BaseDAO { 9?6]Zag
(9A`[TRwi
publicList getUserByName(String name)throws jW!x!8=
5R UhrE
HibernateException; u~-,kF@
c[6=&
publicint getUserCount()throws HibernateException; Rr!oT?6J?
^]_5oFRIj
publicList getUserByPage(Page page)throws UD+r{s/%
f-'$tMs
HibernateException; op|:XLR5
03$lg DQ
} SBbPO5^](
RPh8n4&("
p?#%G`dm
z^YL$
,xzSFs>2
java代码: @Q%g#N
8#_"WzDw
A
$GiO
/*Created on 2005-7-15*/ -:jC.}
Y
package com.adt.dao.impl; 8K;wX%_,
h88IP:bo
import java.util.List; g:&V9