Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 it D%sKo
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "|.>pD#0&
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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 .A&Ey5
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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 y%v<Cp@R
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分页支持类:
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java代码: _+wv3?
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package com.javaeye.common.util; 0r_8/|N#
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import java.util.List; MS_&;2
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publicclass PaginationSupport { B#B$w_z
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publicfinalstaticint PAGESIZE = 30; zTAt% w5
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privateint pageSize = PAGESIZE; %*oz~,i
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privateList items; F2AM/m^!q
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privateint totalCount; h"
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privateint[] indexes = newint[0]; NA]7qb%%<
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privateint startIndex = 0; wU2y<?$\8
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public PaginationSupport(List items, int !5?#^q
*;,=x<
totalCount){ agM.-MK
setPageSize(PAGESIZE); gD@ &/j7
setTotalCount(totalCount); UH%oGp$ykX
setItems(items); Ty*ec%U9F
setStartIndex(0); n&r-
} wI1[I
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public PaginationSupport(List items, int DcQ^V4_
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totalCount, int startIndex){ Hm-+1Wx
setPageSize(PAGESIZE); B(:Kw;r?
setTotalCount(totalCount); 6pLB`1[v
setItems(items); !_?<-f(
setStartIndex(startIndex); $P866F
} awHfd5nRS
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public PaginationSupport(List items, int nbMH:UY,J
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totalCount, int pageSize, int startIndex){ _-o*3gmbQ
setPageSize(pageSize); $Y,,e3R3
setTotalCount(totalCount); ^R,5T}J.
setItems(items); l0U6eOx
setStartIndex(startIndex); >tr_Ypfv,c
} x/[i &Gkv
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publicList getItems(){ 1_fFbb"
return items; ngsax1xO
} OV7vwj/-
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publicvoid setItems(List items){ 3${?!OC
this.items = items; Zj<oh8
} Zv7@
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1
publicint getPageSize(){ c72Oy+#
return pageSize; ~BERs;4
} \xDu#/^
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publicvoid setPageSize(int pageSize){ 6zRJ5uI,/
this.pageSize = pageSize; Te[[xhTyw
} j /)cdP
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publicint getTotalCount(){ ?OZbns~
return totalCount; S4qh8c
} O .TFV.
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publicvoid setTotalCount(int totalCount){ r?{Vqephz
if(totalCount > 0){ Gxi;h=J2)>
this.totalCount = totalCount; JEdtj1v{O
int count = totalCount / (PsA[>F
#7lkj:j4
pageSize; fOE:~3Q
if(totalCount % pageSize > 0) i#kRVua/
count++; 66p_d'U
indexes = newint[count]; D'fP2?3FK
for(int i = 0; i < count; i++){ o4w+)hh
indexes = pageSize * -fL|e/
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i; ^nbze
} s.=)p"pTd
}else{ iUS379wM}
this.totalCount = 0; v
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} k{c~
} }2`S@Rq.WW
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publicint[] getIndexes(){ ^b-H
return indexes; z6Su`
} :]y;t/
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publicvoid setIndexes(int[] indexes){ _N/]&|.. !
this.indexes = indexes; d2.n^Q"?3
} "{z9 L+
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publicint getStartIndex(){ Qbl6~>T
return startIndex; W.MJyem
} g+ 2SB5 2D
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publicvoid setStartIndex(int startIndex){ Vq9hAD|k
if(totalCount <= 0) o&(%:|
this.startIndex = 0; ni2H~{]z
elseif(startIndex >= totalCount) Ic#+*W\ZW
this.startIndex = indexes /rvXCA)j
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[indexes.length - 1]; a Q`a>&R0
elseif(startIndex < 0) ;lYO)Z`3\
this.startIndex = 0;
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else{ KO)<Zh
this.startIndex = indexes OQ+?nB
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[startIndex / pageSize]; 'kH#QO\(e"
} ik8e
}
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publicint getNextIndex(){ g:[&]o} :9
int nextIndex = getStartIndex() + 6Otv[8^}
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pageSize; /jj@ =H
if(nextIndex >= totalCount) ZN1QTb
return getStartIndex(); {GHGFi`Z
else yt!K|g
return nextIndex; f1=8I_>=
} uUc[s"\
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publicint getPreviousIndex(){ 3g-}k
int previousIndex = getStartIndex() - J,7_5V@jJ
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pageSize; 1"v;w!uh
if(previousIndex < 0) 1d\K{ 7i#
return0; *,'"\n
else t8?+yG;
return previousIndex; []dRDe;#
} ioa 1n=j
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} A%Bz52yg
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抽象业务类 3J(STIxg
java代码: kY_UY~E
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/** j<l>+.,
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* Created on 2005-7-12 e;!<3b
*/ NoKYHN^*w
package com.javaeye.common.business; i^QcW!X&
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import java.io.Serializable; 57[O)5u.+
import java.util.List; JRodYXjE
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import org.hibernate.Criteria; \[>Rt
import org.hibernate.HibernateException; {|rwIRe
import org.hibernate.Session; dDm<'30?*v
import org.hibernate.criterion.DetachedCriteria; YDmFR,047
import org.hibernate.criterion.Projections; *-P@|eg
import B"Fg`s+]U
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org.springframework.orm.hibernate3.HibernateCallback; >Zr/U!W*?
import Pc4sReo'
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org.springframework.orm.hibernate3.support.HibernateDaoS 0j_!)B
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upport; P AKh v.7
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import com.javaeye.common.util.PaginationSupport; \lY26'
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public abstract class AbstractManager extends [6/%ynlP
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HibernateDaoSupport { 7
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privateboolean cacheQueries = false; g8qN+Gg
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privateString queryCacheRegion; qY0Ic5wCY
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publicvoid setCacheQueries(boolean 0&mz'xra
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cacheQueries){ V'6%G:?0a
this.cacheQueries = cacheQueries; G7),!Qol
} 5k\61(*s
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publicvoid setQueryCacheRegion(String (JF\%Yj/
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queryCacheRegion){ = j}00,WH
this.queryCacheRegion = L^0jyp
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queryCacheRegion; 3ea6g5kX
} sxuYwQ
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publicvoid save(finalObject entity){ ZM)a4h,kcm
getHibernateTemplate().save(entity); 0#yo\McZ
} Y)a 7osML
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publicvoid persist(finalObject entity){ a]ftE\99
getHibernateTemplate().save(entity); Y)!5Z.K
} `U;4O)`n
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publicvoid update(finalObject entity){ X GO_n{x
getHibernateTemplate().update(entity); n\P{Mc
} cy}2~w&s4
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publicvoid delete(finalObject entity){ Q}m)Q('Rk
getHibernateTemplate().delete(entity); QGYmQ9m{kL
} \
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publicObject load(finalClass entity, 43(+3$V M7
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finalSerializable id){ Put+<o
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return getHibernateTemplate().load C"YM"9JSJ
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(entity, id); mk0rAN
} N2x\O~7
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publicObject get(finalClass entity, #PFf`7b,z
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finalSerializable id){ ?p}m[9@
return getHibernateTemplate().get X#pE!mT
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(entity, id); fwOvlD&e
} m"xw5aa>
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publicList findAll(finalClass entity){ Bh@j6fv
return getHibernateTemplate().find("from 5$jKw\FF=
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" + entity.getName()); ;zp0,[r
} g y&B"`
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publicList findByNamedQuery(finalString :.Np7[~{
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namedQuery){ tTP"*Bb
return getHibernateTemplate CM~)\prks
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().findByNamedQuery(namedQuery); f4:gD*YT
} /tV)8pEj
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publicList findByNamedQuery(finalString query, Pirc49c
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finalObject parameter){ pYVQ-r%QF
return getHibernateTemplate @4H*kA
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().findByNamedQuery(query, parameter); Z.rKV}yjY
} 3VKArv-
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publicList findByNamedQuery(finalString query, ^
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finalObject[] parameters){ NbfV6$jo
return getHibernateTemplate -4"E]f
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().findByNamedQuery(query, parameters); up`!r;5-
} {6A3?q
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publicList find(finalString query){ :3u>%
return getHibernateTemplate().find {3!v<CY'
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(query); k%JwS_F
} s8eFEi
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publicList find(finalString query, finalObject $I+QyKO9k
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parameter){ C:z K{+
return getHibernateTemplate().find @
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(query, parameter); ^P\(IDJCo
} ?r#e
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public PaginationSupport findPageByCriteria .J'}qkz~
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(final DetachedCriteria detachedCriteria){ Wu9@Ecb
return findPageByCriteria yp_:]RE
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); k)dLJ<EM
} OZs^c2
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public PaginationSupport findPageByCriteria Pf-k"7y
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(final DetachedCriteria detachedCriteria, finalint (q"Nt_y
)<t5' +d%
startIndex){ 5c!~WckbJ
return findPageByCriteria 9SXFiZA(r
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(detachedCriteria, PaginationSupport.PAGESIZE, 3<CCC+47
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startIndex); @9-z8PyF
} !A, ]
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public PaginationSupport findPageByCriteria ; Sq_DP1W
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(final DetachedCriteria detachedCriteria, finalint @|idlIey
, 0MDkXb
pageSize, 6/Q'o5>NL:
finalint startIndex){ pMKnA.|
return(PaginationSupport) ^ ,d!K2`
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getHibernateTemplate().execute(new HibernateCallback(){ kW3V"twx
publicObject doInHibernate #\_N-bVu
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(Session session)throws HibernateException { \f5$L`
Criteria criteria = lqTTTk
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detachedCriteria.getExecutableCriteria(session); xJ:15eDC
int totalCount = >A;Mf*E
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((Integer) criteria.setProjection(Projections.rowCount
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()).uniqueResult()).intValue(); [?Wt ZM^q
criteria.setProjection GBFYa6\4sT
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(null); esIEi!d
List items = mw-0n
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criteria.setFirstResult(startIndex).setMaxResults b*\K I
! av
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(pageSize).list(); ~DPjTR
PaginationSupport ps = yO;r]`j0
Az8>^|@
new PaginationSupport(items, totalCount, pageSize, $h"tg9L^)
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startIndex); LJt#c+]Li
return ps; hOx'uO`x(
} & gnE"
}, true); ,`ST Va-
} F#*vJb)
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public List findAllByCriteria(final u^8:/~8K
@`^+XP K\
DetachedCriteria detachedCriteria){ 0&}
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return(List) getHibernateTemplate wt0^R<28
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().execute(new HibernateCallback(){ .DiH)
publicObject doInHibernate 8*-8"It<"
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(Session session)throws HibernateException { 7O^ySy"l
Criteria criteria = mEyJ
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detachedCriteria.getExecutableCriteria(session); c=p`5sN)
return criteria.list(); }OZp[V
} ze@NqCF
}, true); (A|Gb2 X
} DK;p6_tT
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public int getCountByCriteria(final `z=U-v'H)D
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DetachedCriteria detachedCriteria){ $O9Nprf
Integer count = (Integer) u.ubw(vv
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getHibernateTemplate().execute(new HibernateCallback(){ bi;?)7p&ZY
publicObject doInHibernate ,5$V;|
{/#^v?,
(Session session)throws HibernateException { 9JYrP6I!_
Criteria criteria = [@fw9@_'
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detachedCriteria.getExecutableCriteria(session); GVhO}m
return h
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criteria.setProjection(Projections.rowCount EhL
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ofH=h
()).uniqueResult(); ^m8T$^z>
} Dvbrpn!sk
}, true); &7"a.&*9xX
return count.intValue(); /T1zz2l~
} a+sHW<QeS
}
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用户在web层构造查询条件detachedCriteria,和可选的 RZ 4xR
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 zO8`xrN!
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PaginationSupport的实例ps。 g S xK9P
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ps.getItems()得到已分页好的结果集 41Bp^R}^/
ps.getIndexes()得到分页索引的数组 0goKiPx
ps.getTotalCount()得到总结果数 /J!C2
ps.getStartIndex()当前分页索引 D#Fe\8!l
ps.getNextIndex()下一页索引 V;0{o
ps.getPreviousIndex()上一页索引 aV"K%#N
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 DY1?37h
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 64xq@_+
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一下代码重构了。 2r;^OWwr?
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我把原本我的做法也提供出来供大家讨论吧: :&:IZkO
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首先,为了实现分页查询,我封装了一个Page类: {];4
java代码: oz
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/*Created on 2005-4-14*/ i\hH .7G1
package org.flyware.util.page; f[v~U<\R
*AX)QKQ@
/** yem*g1
* @author Joa NCbl|v=
* )#ze
*/ )P4#P2
publicclass Page { Vfew )]I
@gzm4
/** imply if the page has previous page */ 3l5rUjRwj
privateboolean hasPrePage; #;cDPBv*wS
KQ'fp:5|/@
/** imply if the page has next page */ .C=&`;Vs
privateboolean hasNextPage; 3&i8C,u]/O
dv3+x\`9
/** the number of every page */ [ox!MQ+s
privateint everyPage; /?X1>A:*
_|%pe]St
/** the total page number */ X&qRanOP;z
privateint totalPage; JmN,:bI
w6tb vhcmU
/** the number of current page */ jRIjFn|~{Y
privateint currentPage; :()(P9?
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/** the begin index of the records by the current ^pz3L'4n
ONQp-$
query */ J]uYXsC
privateint beginIndex; ~/?JRL=
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/** The default constructor */ _nu
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public Page(){ _i [.5
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} *0bbSw1kc
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/** construct the page by everyPage `K[:<p}
* @param everyPage tm\ <w H
* */ FI@2KM
public Page(int everyPage){ ^9T6Ix{=
this.everyPage = everyPage; EFeG[bxM
} !NuYx9L?L
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)(2|
/** The whole constructor */ !fdni}f)
public Page(boolean hasPrePage, boolean hasNextPage, {#M=gDhbX
u:H@]z(x
9_IR%bm
int everyPage, int totalPage, }D.?O,ue
int currentPage, int beginIndex){ ?#]K54?
this.hasPrePage = hasPrePage; Yjz'lWg
this.hasNextPage = hasNextPage; wd*i&ooQ*L
this.everyPage = everyPage; -k\7k2
this.totalPage = totalPage; N>i1TM2
this.currentPage = currentPage; aM'0O![d
this.beginIndex = beginIndex; ,-u | l
} =!NYvwg6;o
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/** }i_[wq{E&
* @return b7fP)nb695
* Returns the beginIndex. 2L.UEAt
*/ Q6?+# }
publicint getBeginIndex(){ g#FqjE|mx
return beginIndex; uF5d
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} 2^Gl;3
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/** ?!(/;RU1
* @param beginIndex W.p->,N
* The beginIndex to set. GV)#>PL
*/ e1{t qNJ
publicvoid setBeginIndex(int beginIndex){ bj`cYL%
this.beginIndex = beginIndex; ]!H*oP8a*
} :j$K.3n
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/** 1DcYc-k#
* @return SqY;2:
* Returns the currentPage. sw*k(i
*/ {npKdX
publicint getCurrentPage(){ aA%$<ItH
return currentPage; q p|T,D%
} ,G1|]
~
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/** xt
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* @param currentPage i2b\`
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* The currentPage to set. ;nj 'C1
*/ ~bT0gIc
publicvoid setCurrentPage(int currentPage){ [$?S9)Xd
this.currentPage = currentPage; Kbx (^f12
} Q3%a=ba)h
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/** 0<{/T*AU:
* @return mquna"}N
* Returns the everyPage. !_<. 6ja
*/ `{I,!to
publicint getEveryPage(){ $Z10Zf=
return everyPage; uW;Uq=UN
} _wM[U`H}s
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/** wd*T"V3
* @param everyPage F-k1yZ?^
* The everyPage to set. 8!>uC&bE8
*/ DS>s_3V
publicvoid setEveryPage(int everyPage){ /(n)I
this.everyPage = everyPage; : ` F>B
} eHv~?b5l
KGi@H%NN
/** @babgP,
* @return 9 )B >|#\
* Returns the hasNextPage. g^)> -$=
*/ <!X'- >i%q
publicboolean getHasNextPage(){ HAo8]?J
return hasNextPage; ] >ipC,v
} Djf2ir'
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/** /dOQ4VA\
* @param hasNextPage =i%2/kdi0b
* The hasNextPage to set. PyYKeo=
*/ !::k\}DS
publicvoid setHasNextPage(boolean hasNextPage){ pY =?r{@
this.hasNextPage = hasNextPage; spO?5#
} o~P8=1t
3}g?d/^E3
/** (]1le|+
* @return E\m?0]W|
* Returns the hasPrePage. i04Sf^
*/ >jl"Yr#
publicboolean getHasPrePage(){ a^[io1}-
return hasPrePage; \<lV),
} 0 {{7 "
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/** $6!`
* @param hasPrePage ::H jpM
* The hasPrePage to set. ' 1P_*
*/ U\VwJ2
{i
publicvoid setHasPrePage(boolean hasPrePage){ ie.cTTOI
this.hasPrePage = hasPrePage; gK)B3dH*&
} tY# F8a&
5@[%P=
/** }sJ%InL
* @return Returns the totalPage. 0SKt8pL`
* ;t?pyFT2Z
*/ Ur&: Rr
publicint getTotalPage(){ aqzvT5*8%
return totalPage; iT^lk'?{O
} P#ru-0DD
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/** ?U-p
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* @param totalPage '[-H].-!
* The totalPage to set. #i2q}/w5`C
*/ :L`z~/6
publicvoid setTotalPage(int totalPage){ kIWQ`)'
this.totalPage = totalPage; fI$,?>
} |?8CV\D!
gX(QRQ
} v?LJ_>hw*T
=?*V3e3{
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M$&>"%Oi
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 z%g<&Cq
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个PageUtil,负责对Page对象进行构造: ["L?t ^*G
java代码: R*yB); p
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/*Created on 2005-4-14*/ V;:A&
package org.flyware.util.page; b/5~VY*T
> %Y#(_~a
import org.apache.commons.logging.Log; nQ~q-=,L
import org.apache.commons.logging.LogFactory; uwQ4RYz
,MvvW{EY
/** MPL2#YU/a
* @author Joa / TJTu_#
* \'p7,F{:>5
*/ W}=2?vHV=
publicclass PageUtil { ]iNSa{G
v#/,,)m
privatestaticfinal Log logger = LogFactory.getLog uPo>?hpq+
n--`zx-['
(PageUtil.class); 6|jE3rHw
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/** X*Q7Yu
* Use the origin page to create a new page
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* @param page }Ql;% 7
* @param totalRecords s[s^z<4G
* @return 9n%W-R.
*/ ljf9L:L
publicstatic Page createPage(Page page, int ]g)%yuox9F
ovfw _
totalRecords){ 1Gqtd^*;
return createPage(page.getEveryPage(), dl;A'/(t
_|Dt6
page.getCurrentPage(), totalRecords); B " B
} 0y ;gi3W
c`jTdVD
/** m76]INq
* the basic page utils not including exception g,W#3b6>j
:-
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handler d8r+UP@#
* @param everyPage bQeYFY#^
* @param currentPage 0yZw`|Zh[
* @param totalRecords 34l=U?
* @return page D@ lJ^+
*/ .s9Iymz
publicstatic Page createPage(int everyPage, int $fn^i.
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currentPage, int totalRecords){ d)AkA\neWo
everyPage = getEveryPage(everyPage); w'eenIX^^
currentPage = getCurrentPage(currentPage); 07MLK8jS
int beginIndex = getBeginIndex(everyPage, #nxx\,i>
u4nXK
<KL|
currentPage); xAO]u[J
int totalPage = getTotalPage(everyPage, h7w<.zwu
t
U!`'Qw;
totalRecords); *K 7L5.
boolean hasNextPage = hasNextPage(currentPage, (l^lS=x
:Oj+Tc9A
totalPage); l00D|W_9
boolean hasPrePage = hasPrePage(currentPage); lGz0K5P{
XDWERvIj
returnnew Page(hasPrePage, hasNextPage, EtcamI*`
everyPage, totalPage, Xg)yz~Ug
currentPage, }B.C#Y$@
j)0R*_-B[
beginIndex); Nl8Cctrf
}
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t.TQ@c+,J
privatestaticint getEveryPage(int everyPage){ oe<Y,%u"6
return everyPage == 0 ? 10 : everyPage; hh{liS% 10
} d"cfSH;h
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privatestaticint getCurrentPage(int currentPage){ uXC?fMWp.
return currentPage == 0 ? 1 : currentPage; JQCwI`%i
} 6]3ZUH;
3$b(iI< "
privatestaticint getBeginIndex(int everyPage, int :tgTYIF
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currentPage){ 5C&f-* Bh
return(currentPage - 1) * everyPage; {V&7JZl,/
} c%dy$mkqgK
!<)_ F
privatestaticint getTotalPage(int everyPage, int -$q/7,os
; n@C(hG
totalRecords){ g=(+oK?
int totalPage = 0; aVb]H0
*l^'v9
if(totalRecords % everyPage == 0) d7P @_jO6
totalPage = totalRecords / everyPage; ba ?k:b
else Ss:,#|
totalPage = totalRecords / everyPage + 1 ; +g[B &A!d+
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return totalPage; ._3NqE;
} .R'i=D`Pz
i=D,T[|>a
privatestaticboolean hasPrePage(int currentPage){ ^&.?kJM
return currentPage == 1 ? false : true; LA+MX0*
} v3"xJN_,[p
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privatestaticboolean hasNextPage(int currentPage, ?X1#b2s
r;C\eN
int totalPage){ x(`$D
return currentPage == totalPage || totalPage == rZv+K/6*M
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0 ? false : true; ,Aii>D]
} ;cr6Xop#?
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} WdAGZUp
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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。 qrc/Q;$
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面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 L'Zud,JKg
3c3Z"JV
做法如下: 3Y-v1.^j
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 H~i],WD
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的信息,和一个结果集List: <T[N.mB
java代码: *F*X_O
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/*Created on 2005-6-13*/ @45 H8|:k
package com.adt.bo; [u80-x<
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import java.util.List; hhGpB$A
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import org.flyware.util.page.Page; CE,Om^
@U{M"1zZe
/** #:|?t&On
* @author Joa JZzf,G:
*/ .M2&ad :
publicclass Result { %Be[DLtE"
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private Page page; >EtP^Lu~f_
HW726K*
private List content; dA/o4co
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/** zDyeAxh4
* The default constructor x Ui!|c
*/ QJWES%m`
public Result(){ 9Oyi:2A
super(); ]4mj 1g&C
} ->I{
:#
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/** 3 ?F@jEQk
* The constructor using fields >-lL-%N_
* H$amt^|zQ4
* @param page X&.$/xaT
* @param content p,\bez
*/ {K4t8T]
public Result(Page page, List content){ [E
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this.page = page; X-#mv|3
this.content = content; JK"uj%
} .oj" ru
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/** ?]D+H%3[$i
* @return Returns the content. ;}~Bv<#
*/ YwWTv
publicList getContent(){ }#*zjMOz
return content; Z'dI!8(Nf
} r/sRXM:3cZ
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/** OW}j4-~wL
* @return Returns the page. jjT2k
*/ KH>sCEt
public Page getPage(){ <S@mQJS!y
return page; vC<kpf!
} ]#q7}Sd
)^S^s>3
/** b[o"Uq@8?
* @param content 50bP&dj&
* The content to set. |uwteG5?$s
*/ TL{pc=eBo
public void setContent(List content){ .N5R?fmD
this.content = content; rbun5&RCyW
} Pq\V($gN
Z?v6pjZ?
/** iH}rI'U.
* @param page Po!JgcJ#\
* The page to set. 'Oy5G7^R
*/ {R!TUQ5
publicvoid setPage(Page page){ 8tRhV2
this.page = page; +Y9D!=_lj
} -_*XhD
} B
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p
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2. 编写业务逻辑接口,并实现它(UserManager, 4i\aW:_'i
^=Tu>{uD
UserManagerImpl) h8= MVh(I
java代码: <T.#A8c
C\2 >7
UFAMbI
/*Created on 2005-7-15*/ hPi
:31-0
package com.adt.service; 0R 5^p
2td|8vDA
import net.sf.hibernate.HibernateException; -kri3?Y,
X.AWs=:-
import org.flyware.util.page.Page; 'j<:FUDJ
[(P[qEY
import com.adt.bo.Result; <\9Ijuq}k
\
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/** Nw$[a$^n
* @author Joa ^AjYe<RU}
*/ ,-IF++q
publicinterface UserManager { ]G
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l)rvh#D
public Result listUser(Page page)throws awSS..g}L
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HibernateException; 3G/ mB
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} iMeRQYW
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5nM9!A\D
>-|90CSdSJ
java代码: <
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