Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9L>73P{_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 qOflvf
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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 z\-/R9E/5-
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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 ^t?vv;@}
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。 M_h8{
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分页支持类: D*'sO B(
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java代码: iL|5}x5\
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package com.javaeye.common.util; Q_`EKz;N{
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import java.util.List; jB,VlL
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publicclass PaginationSupport { K"zRj L+
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publicfinalstaticint PAGESIZE = 30; qq"0X! w
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privateint pageSize = PAGESIZE; ?8FJMFv;4%
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privateList items; ~Rw][Ys
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privateint totalCount; HLPY%VeD
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privateint[] indexes = newint[0]; nF]zd%h
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privateint startIndex = 0; 9W&nAr
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public PaginationSupport(List items, int Bm 4$
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totalCount){ <j1r6.E)
setPageSize(PAGESIZE); "JE->iD
setTotalCount(totalCount); %~[@5<p
setItems(items); pJIJ"o'>.9
setStartIndex(0); zm3$)*p1
} eQ*zi9na
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public PaginationSupport(List items, int @sUec
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totalCount, int startIndex){ n<1*cL:8B
setPageSize(PAGESIZE); D^6Q`o
setTotalCount(totalCount); jp|*kBDq\
setItems(items); 4I#@xm8)
setStartIndex(startIndex); h]/3doP
} gAgF$H .
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public PaginationSupport(List items, int \Nk578+AA
! F<::fN
totalCount, int pageSize, int startIndex){ FiSx"o
setPageSize(pageSize); &?5me:aU
setTotalCount(totalCount); \jb62Jp
setItems(items); +No` 89Y
setStartIndex(startIndex); {^k7}`7,
} Gd$!xN%O
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publicList getItems(){ WJk3*$=
return items; 39I|.B"
} <
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publicvoid setItems(List items){ >">Xd@Wk
this.items = items; 8#[2]1X^8
} f4VdH#eng`
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publicint getPageSize(){ 7}e5a c
return pageSize; z]D/Qr
} {$>.I
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publicvoid setPageSize(int pageSize){ FAX[|p
this.pageSize = pageSize; }z,9!{~`
} nJ$2RN
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publicint getTotalCount(){ FL4BdJ\
return totalCount; Z<QNzJ D
} pH(X;OC9S
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publicvoid setTotalCount(int totalCount){ ,3!TyQ\m'
if(totalCount > 0){ 3!%-O:!
this.totalCount = totalCount; E)wf'x
int count = totalCount / ,5j3(Lk
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pageSize; nW<nOKTnk_
if(totalCount % pageSize > 0) uG/'9C6Z
count++; AMASh*
indexes = newint[count]; KzQFG)q ,
for(int i = 0; i < count; i++){ *IIA"tC
indexes = pageSize * )2# qi/
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i; `TH\0/eE
} R / ND f`
}else{ A~X\ dcn
this.totalCount = 0; =yoR>llbBC
} (?TK P 7
} /F46Ac}I
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publicint[] getIndexes(){ :*^aSPlV
return indexes; A%x0'?GU
} FHEP/T\5
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publicvoid setIndexes(int[] indexes){ mwsdl^c
this.indexes = indexes; apt$e$g
} vif)g6,
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publicint getStartIndex(){ j\zlp
return startIndex; r^H,H'BohJ
} /^v!B`A@
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publicvoid setStartIndex(int startIndex){ 1hSV/%v_
if(totalCount <= 0) Z>3m-:-e
this.startIndex = 0;
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elseif(startIndex >= totalCount) 5g
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this.startIndex = indexes m*YfbOhs#
o^Lq8u;i*
[indexes.length - 1]; *$`N5;7'`
elseif(startIndex < 0) sKJr34
this.startIndex = 0; 0-;>O|U3
else{ =vvd)og
this.startIndex = indexes lrL:G[rt
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[startIndex / pageSize]; a)c;z@r
} =f [/Pv
} Zu~w:uNmU
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publicint getNextIndex(){ !^s -~`'\~
int nextIndex = getStartIndex() + iOSt=-p
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pageSize; Lusd kc7
if(nextIndex >= totalCount) #XB3Wden2
return getStartIndex(); }q'IY:r
else 87W!R<G
return nextIndex; vLBuE
} W7gY$\1<&
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publicint getPreviousIndex(){ uB3VCO.;_
int previousIndex = getStartIndex() - {2mF\A#.
m#i4_F=^b
pageSize; >)G[ww[
if(previousIndex < 0) t&F:C
return0; "'@D\e}
else S=.%aB
return previousIndex; V6'u\Ch|
} |=0w_)Fa]
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} = :zPT;K
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抽象业务类 7U1M;@y
java代码: ,4`Vl<6
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/** 9nY|S{L
* Created on 2005-7-12 B$YoglEW:
*/ -mGG:#yP
package com.javaeye.common.business; 0l& '`
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import java.io.Serializable; <DPRQhNW]
import java.util.List; jkta]#O
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import org.hibernate.Criteria; B!;:,(S~
import org.hibernate.HibernateException; r_T"b
import org.hibernate.Session; r@]`#PL
import org.hibernate.criterion.DetachedCriteria; ,x!r^YO=
import org.hibernate.criterion.Projections; oXqJypR 2
import qg1\ABH
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w
org.springframework.orm.hibernate3.HibernateCallback; JZ![:$:
import (*=>YE'V{
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org.springframework.orm.hibernate3.support.HibernateDaoS @ S[As~9X
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upport; VpAwvMw
@ext6cFe3<
import com.javaeye.common.util.PaginationSupport; r&B0-7r
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public abstract class AbstractManager extends S)wP];]`K
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HibernateDaoSupport { 9-q> W
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privateboolean cacheQueries = false; cYe2a"
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privateString queryCacheRegion; ,}@4@ >?K
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publicvoid setCacheQueries(boolean 4X7J~
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cacheQueries){ + 9|0\Q
this.cacheQueries = cacheQueries; 00f'G2n
} .5!`wwVi
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publicvoid setQueryCacheRegion(String ]s^+/8d=
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queryCacheRegion){ !.q99DB
this.queryCacheRegion = }F/w34+;
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}@^Gk
queryCacheRegion; 53ZbtEwhwr
} <82&F
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publicvoid save(finalObject entity){ F=w:!tqA
getHibernateTemplate().save(entity); oIx|)[
} *` wz
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publicvoid persist(finalObject entity){ yocFdI
getHibernateTemplate().save(entity); 4e
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} RXcN<Y&
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publicvoid update(finalObject entity){ \,X)!%6kZ
getHibernateTemplate().update(entity); !9YCuHj!p
} $ (xdF
1 n&%L8]
publicvoid delete(finalObject entity){ Sw"h!\c`
getHibernateTemplate().delete(entity); P(2OTfGGx
} ezY^T
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publicObject load(finalClass entity, Oso**WUOZ&
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finalSerializable id){ p%sizn
return getHibernateTemplate().load %kop's&?C
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(entity, id); O $e"3^Pa
} ",vK~m2W_
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publicObject get(finalClass entity, Ee7+ob
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finalSerializable id){ {~FPvmj&
return getHibernateTemplate().get "+7E9m6I
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(entity, id); M&29J
} Ug546Bz
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publicList findAll(finalClass entity){ na~ FT[3C
return getHibernateTemplate().find("from Me?I8:/
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" + entity.getName()); .N.RpRz{f
} #-f9>S9_
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publicList findByNamedQuery(finalString X])iQyN
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namedQuery){ U?{oxy_[ 2
return getHibernateTemplate Wu|MNB?M
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().findByNamedQuery(namedQuery); /ILd|j(e
} eIF6f&
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publicList findByNamedQuery(finalString query, [?9 `x-Q
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finalObject parameter){ VY8cy2
return getHibernateTemplate Cm%I/4
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().findByNamedQuery(query, parameter); %~M* <pN
} uo2k
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publicList findByNamedQuery(finalString query, 4TPdq&';C:
*<67h*|)
finalObject[] parameters){ r5nHYV&7
return getHibernateTemplate gYrB@W;2
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().findByNamedQuery(query, parameters); `|Di?4+6%
} #|Lsi`]+
*'A*!=5(
publicList find(finalString query){ c?_7e9}2
return getHibernateTemplate().find 1 /{~t[*.
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(query); !a:e=b7g
} @M-w8!.~
}}]Lf 3;
publicList find(finalString query, finalObject _Y&.Nw
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parameter){ $6*Yh-"g
return getHibernateTemplate().find "p;tj74O9
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(query, parameter); &uO-h
} 612,J
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public PaginationSupport findPageByCriteria '5$@I{z
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(final DetachedCriteria detachedCriteria){ C^4,L
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return findPageByCriteria 3fQ`}OcNr
=d ;#Nu-
(detachedCriteria, PaginationSupport.PAGESIZE, 0); PpG;5
} uyk;]EYjHZ
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public PaginationSupport findPageByCriteria E8#aE\'t
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(final DetachedCriteria detachedCriteria, finalint H9ES|ZJs
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startIndex){ \WC,iA%Y
return findPageByCriteria +CdUr~6
e>e${\=,
(detachedCriteria, PaginationSupport.PAGESIZE, nyR<pnuC'
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startIndex); )mwwceN
} pA_u;*
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint uk$MQv*D
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pageSize, l]wLQqoO
finalint startIndex){ p\;8?x
return(PaginationSupport) %RtL4"M2j
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getHibernateTemplate().execute(new HibernateCallback(){ gvWgw7z
publicObject doInHibernate /LWk>[Z;
;-py h(
(Session session)throws HibernateException {
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Criteria criteria = ,T
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detachedCriteria.getExecutableCriteria(session); T|BlFJ0"
int totalCount = -A<@Pg
7"aN7Q+EbI
((Integer) criteria.setProjection(Projections.rowCount &gS-.{w "
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()).uniqueResult()).intValue(); l"dXL"h
criteria.setProjection c\rP
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}UGSE2^1
(null); )Z/w|5<
List items = P
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9{A4>
criteria.setFirstResult(startIndex).setMaxResults
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Tb2#y]27
(pageSize).list(); o*7NyiJ@z
PaginationSupport ps = 6U8esPs,
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new PaginationSupport(items, totalCount, pageSize, Jv3G\9_
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startIndex); 1U/9=b
return ps;
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} RZ{O6~VH
}, true); Lks+FW
} v07A3oj
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public List findAllByCriteria(final af@a /
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DetachedCriteria detachedCriteria){ GQYn |vm
return(List) getHibernateTemplate ]5a3e+
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().execute(new HibernateCallback(){ `.~S/$a.&
publicObject doInHibernate w<!,mL5 N
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(Session session)throws HibernateException { =d"5kDK-m
Criteria criteria = LD?\gK"
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detachedCriteria.getExecutableCriteria(session); *74/I>i
return criteria.list(); 19O
} -U$;\1--
}, true); ;J+iwS*Z
} s Adb0 A
}8}`A\dgV
public int getCountByCriteria(final J^#g?RHN>m
N\tFK*U^I
DetachedCriteria detachedCriteria){ 2eRk_j]
Integer count = (Integer) fHZ9wK>
i qxMTH#!
getHibernateTemplate().execute(new HibernateCallback(){ 1|G\&T
publicObject doInHibernate nJv=kk1|o
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(Session session)throws HibernateException {
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Criteria criteria = s1[.L~;J
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detachedCriteria.getExecutableCriteria(session); ~cO iv
return vdUKIP
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criteria.setProjection(Projections.rowCount kUGFg{"
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()).uniqueResult(); d#d&CJAfr
} lcpiCZ
}, true); Z VdQ$
return count.intValue(); a"O;DYh
} p]y.N)a
} SfY 5Xgp
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用户在web层构造查询条件detachedCriteria,和可选的 1]0;2THx
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0'A"]6
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PaginationSupport的实例ps。 sb_/FE5e
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ps.getItems()得到已分页好的结果集 Qp:m=f6@
ps.getIndexes()得到分页索引的数组 (4q/LuP^d
ps.getTotalCount()得到总结果数 j$6Q]5KdoS
ps.getStartIndex()当前分页索引 ,2FI?}+R
ps.getNextIndex()下一页索引 i E;F=Rb
ps.getPreviousIndex()上一页索引 oVp/EQ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 FY)]yz
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 JP( tf+
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一下代码重构了。 T)q
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我把原本我的做法也提供出来供大家讨论吧: 2PeMt^
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首先,为了实现分页查询,我封装了一个Page类: oXk6,b"
java代码: jvR(e"
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/*Created on 2005-4-14*/ `h :!^"G
package org.flyware.util.page; hD?6RVfG
_ 3>E+9TQ
/** Q qj9o2
* @author Joa >e-0A
* w9"~NK8xzM
*/ ;{R;lF,
publicclass Page { jHHCJOHB8
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/** imply if the page has previous page */ %c]N-
privateboolean hasPrePage; =\ 5f_g2M
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/** imply if the page has next page */ tZg)VJQys
privateboolean hasNextPage; vy={ziJ
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/** the number of every page */ /D|q-`*K
privateint everyPage; aTH$+f1?Q
!RwhVaSh
/** the total page number */ y.8nzlkE{
privateint totalPage; y#`;[!
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/** the number of current page */ =\)zb '\=d
privateint currentPage; };P=|t(r
rxy5Nrue
/** the begin index of the records by the current >P} XCAU
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query */ K(lVAKiP]
privateint beginIndex; ;;CNr_
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/** The default constructor */ 1!U:M8T|
public Page(){ +mR^ I$9
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} H)&iFq
_):@C:6
/** construct the page by everyPage GCw4sb4~w
* @param everyPage 0SIUp/.
* */ {<}Hut:a
public Page(int everyPage){ \WdSj
this.everyPage = everyPage; VhMVoW
} #
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/** The whole constructor */ GA[bo)"
public Page(boolean hasPrePage, boolean hasNextPage, c3#eL
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<u#
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int everyPage, int totalPage, @ %q>Jd
int currentPage, int beginIndex){ .YB/7-%M[
this.hasPrePage = hasPrePage; .rwW5"RPq
this.hasNextPage = hasNextPage; Nq9M$Nt]
this.everyPage = everyPage; 6r@>n_6LY
this.totalPage = totalPage; / <+`4n
this.currentPage = currentPage; cAVdH{$"
this.beginIndex = beginIndex; lMg#zT!?
} $txF|Fj]^A
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/** c(5XT[Tw
* @return :.a184ax
* Returns the beginIndex. %WmTG }L)
*/ <*u^8lCA
publicint getBeginIndex(){ @;hdZLG]`&
return beginIndex; (w(k*b/
} 1L7^g*
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/** uD{ xs
* @param beginIndex s0x/2z
* The beginIndex to set. =h
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*/ bd27])n(
publicvoid setBeginIndex(int beginIndex){ 1Q9Hs(s
this.beginIndex = beginIndex; JqYa~6 C
} >YF=6zq.`
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/** 7D'D7=Z.
* @return 3a ZS1]/
* Returns the currentPage. mtE+}b@(!&
*/ 0fUsERr1*
publicint getCurrentPage(){ @}{uibLD\
return currentPage; .O#7X
} w?N>3`Jnf
O%F*i2I:+k
/** ouFKqRs;
* @param currentPage JxLfDr,dy
* The currentPage to set. uKD
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*/ ,D<U PtPQ
publicvoid setCurrentPage(int currentPage){ =i;T?*@
this.currentPage = currentPage; OpIeo+^X*
} w2('75$J
UH\{:@GjNO
/** VUHf-bKl
* @return E
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* Returns the everyPage. 1:@ScHS
*/ ke<5]&x
publicint getEveryPage(){ Lh.-*H
return everyPage; \\Q){\S
} 3=Rk(%:;
5e7\tBab
/** =43NSY
* @param everyPage L8NZU*"
* The everyPage to set. FDGG$z?>m
*/ n^5Q
f\ o
publicvoid setEveryPage(int everyPage){ -F3~X R
this.everyPage = everyPage; 5gC>j(
} 5e0d;Rd
),j6tq[
/** bF+j%=
* @return tw\1&*:
* Returns the hasNextPage. F`{O
*/ E m +&I
publicboolean getHasNextPage(){ Rxlv:
return hasNextPage; V U5</si+
} zx.SRs$
"sY}@Q7
/** y>gw@+
* @param hasNextPage r{SDJa
* The hasNextPage to set. 87!m l
*/ '^[+]
publicvoid setHasNextPage(boolean hasNextPage){ w8J8III\~
this.hasNextPage = hasNextPage; Zt=P 0
} y+{)4ptg$<
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/** p
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* @return fy|I3
* Returns the hasPrePage. m@w469&<(q
*/ RQ^
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publicboolean getHasPrePage(){ W@'*G*f
return hasPrePage; CY[3%7fv
} $4)L~g|
r=AA
/n<
/** hk
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* @param hasPrePage UTN[!0[
* The hasPrePage to set. BS?$eai@:9
*/ bz~aj}"`
publicvoid setHasPrePage(boolean hasPrePage){ [/ertB
this.hasPrePage = hasPrePage; y}|E)
} owVks-/
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/** 8IBr#+0
* @return Returns the totalPage. ib!TXWq
* A:yql`&s
*/ h.l.da1#
publicint getTotalPage(){ y
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return totalPage; gjX1 z{{~L
} T.-tV[2
zn_#}}e;G
/** 7-~)/7L
* @param totalPage ~%f$}{
* The totalPage to set. k#8`996P
*/ bw7g L\*
publicvoid setTotalPage(int totalPage){ u7Ix7`V
this.totalPage = totalPage; ZW0\_1
} <8Nr;96IA
hdSP#Y'-
} bQwG"N
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&rPAW V'v
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FH$q,BI!R
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 uwZ,l-6T
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个PageUtil,负责对Page对象进行构造: HJ0;BD.]
java代码: !y'>sAf
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/*Created on 2005-4-14*/ T:H~Y+qnt
package org.flyware.util.page; Iwh0PfWJ
j|N<6GSke
import org.apache.commons.logging.Log; n"D` =
import org.apache.commons.logging.LogFactory; ~UNha/nt
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/** $|3zsi2
* @author Joa M+HhTW;I=
* TJZ~Rpq
*/ ^~7Mv^A
publicclass PageUtil { !IO\g"y~|%
SBs! 52
privatestaticfinal Log logger = LogFactory.getLog q5'G]j{,Z
]FIIs58IM
(PageUtil.class); d!Gy#<H
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/** tY!l}:E[
* Use the origin page to create a new page '`2MxRP
* @param page S4{vS?>j
* @param totalRecords bGK*1FlH
* @return jX(${j<
*/ U=69q]
publicstatic Page createPage(Page page, int o9]32l
e.%I#rNI
totalRecords){ {#4a}:3
return createPage(page.getEveryPage(), UntFkoO
[6JDS;MIN
page.getCurrentPage(), totalRecords); :9%e:-
} Dykh|"
f5b|,JJ
/** 3!fR'L/i
* the basic page utils not including exception cRD;a?0/6s
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handler wCR! bZ w
* @param everyPage ecoI-@CAI
* @param currentPage 8 sc2r
* @param totalRecords &ZkJ,-
* @return page lX"m|W
*/ 2y!aXk\#C
publicstatic Page createPage(int everyPage, int
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currentPage, int totalRecords){ b$fmU"%&|
everyPage = getEveryPage(everyPage); O2pE"8=4Q
currentPage = getCurrentPage(currentPage); +_cigxpTc
int beginIndex = getBeginIndex(everyPage, &|ne!wu
KW[y+c u.#
currentPage); q0Q[]|L
int totalPage = getTotalPage(everyPage, "RK"Pn+
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totalRecords); C,W_0=!e
boolean hasNextPage = hasNextPage(currentPage, A:GqR;;"x>
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totalPage); e7{6<[k3+$
boolean hasPrePage = hasPrePage(currentPage); 3C%|src
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returnnew Page(hasPrePage, hasNextPage, Sk!' 2y*@&
everyPage, totalPage, *GBV[D[G,
currentPage, L/-SWid)
ol/@)k^s>
beginIndex); nAl
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} )$9wKk\F
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privatestaticint getEveryPage(int everyPage){ 7qOkv1.}0
return everyPage == 0 ? 10 : everyPage; _BerHoQd
} gWa0x-
jy5[K.
privatestaticint getCurrentPage(int currentPage){ %H"
return currentPage == 0 ? 1 : currentPage; IE996
} Oy=0Hsh@x
iJOG"gI&
privatestaticint getBeginIndex(int everyPage, int f>C+ l(
]w;t0Bk
currentPage){ 50-7L,
return(currentPage - 1) * everyPage; Dbj?l;'1
}
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nA("
cD[,
privatestaticint getTotalPage(int everyPage, int /4pYhJ8S
lqL5V"2Y
totalRecords){ ArAe=m!u
int totalPage = 0; JvW7h(u7g
~(XaXu
if(totalRecords % everyPage == 0) \EoE/2"<
totalPage = totalRecords / everyPage; -p)`o b-
else nKr'cb
totalPage = totalRecords / everyPage + 1 ;
f&^}yqmuE
3MHpP5C
return totalPage; p19(>|$J
} .$x}~Sw
9v*y&V9/
privatestaticboolean hasPrePage(int currentPage){ 1
Vt,5o5
return currentPage == 1 ? false : true; >h#juO"
} mkyYs[
lV^:2I/
privatestaticboolean hasNextPage(int currentPage, ejkUNCKQt
/ZabY
int totalPage){ ri59LY y=
return currentPage == totalPage || totalPage == ">t^jt{
uchQv]VB
0 ? false : true; T3
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} ,"#nJC
hf9i%,J
)z74,n7-
} 4vG-d)"M2
@^ YXE,
cRr3!<EZ
;r"r1'a+@
%gFIu.c
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 l6w\E=K
>\pF5a`
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 %u&Vt"6m=
tyW[i8)O}
做法如下: h'h8Mm
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,z#D[5
C}xfo}i
的信息,和一个结果集List: KP0(w(q
java代码: ~b)X:ku
>m1b/J3#
"A~dt5GJ
/*Created on 2005-6-13*/ &ot^+uVH
package com.adt.bo; W[)HFh(#
hkb\GcOj
import java.util.List; }DjVZ48
!\%JOf}
import org.flyware.util.page.Page; oi7k#^
=
E_i
/** Y]`=cR`/"
* @author Joa XZ@+aG_%q
*/ _('
@'r
publicclass Result { .@nfqv7{
?_AX;z
private Page page; 8i73iTg(
Z9 ws{8@_
private List content; w)vpo/?
vmkiw1
/** zsQkI@)sO
* The default constructor r-EIoZ"P
*/ Y)]VlV!`
public Result(){ C/N;4
super(); [O_5`X9|
} wAi7jCY%OY
sRcd{)|Cq
/** EmUn&p%hI
* The constructor using fields [&&#~gz
* 2@Nd02v|
* @param page Wll0mtv
* @param content ^vG<Ma.yk
*/ (NR( )2
public Result(Page page, List content){ `&fW<5-
this.page = page; dPpQCxf
this.content = content; GR*sk#{
} Hc\@{17
=2GKv7q$x,
/** [Fag\/Y+
* @return Returns the content. 8(K:2
*/ ,R-k]^O
publicList getContent(){ xu-bn
return content; RE4#a2
} O_2o/
m2(}$z3e
/** Ucy=I$"
* @return Returns the page. Q
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*/ [>p!*%m
public Page getPage(){ (
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return page; ;5\'PrE
} Ofoh4BL'1@
R>:D&$[RD
/** C "@>NC_
* @param content V!]|u ^4I
* The content to set. _I'k&R
*/ y7#+VF`xf
public void setContent(List content){ o?M ;f\Fy
this.content = content; TeZu*c
} h2mHbe43
\oxf_4X
/** [Pp#r&4H
* @param page -t<1A8%
* The page to set. b g0ix"
*/ =m (u=|N3
publicvoid setPage(Page page){ 0k\,z(e
this.page = page; A~>B?Wijqg
} ?rt[
aK
} z)*{bz]
PEjd
q*4@d)_&
i}>EGmv m
NqKeQezX
2. 编写业务逻辑接口,并实现它(UserManager, 8|i<4>
Y~^R^J
UserManagerImpl) $;ny`^8
java代码: |p*cI @
X_Lt{mf
2,I]H'}^
/*Created on 2005-7-15*/ GK11fZpO:i
package com.adt.service; s-SFu
n'pJl
import net.sf.hibernate.HibernateException; ON!Fk:-
@ kv~2m
import org.flyware.util.page.Page;
}8"i~>>a
17l?li
import com.adt.bo.Result; pg,JYn
.sj/Lw}
/** QRl+7V
* @author Joa d?YSVmG
*/ sLTQm*jL
publicinterface UserManager { UL~~J[1r
HXdo:#xEO
public Result listUser(Page page)throws /u]#dX5
?@MY +r_G
HibernateException; t Jtp1$h
`]19}GK~xo
} M!gu`@@}F
CUC]-]8
#]Do_Z
JCZ&TK
69ycP(
java代码: 9w&CHg7D
i
}>,%El/
VpbJe@*D
/*Created on 2005-7-15*/ bqF?!t<B
package com.adt.service.impl; 4C:dkaDq]
%t9Kc9u3p
import java.util.List; +",`Mb
16z
WmJH
import net.sf.hibernate.HibernateException; v=dN$B5y3
q:jv9eL.O
import org.flyware.util.page.Page; @sd{V
import org.flyware.util.page.PageUtil; M,{; xf
0$yHO2 f
import com.adt.bo.Result; Ae^4
import com.adt.dao.UserDAO; l)DcwkIG
import com.adt.exception.ObjectNotFoundException; 6oq^n
s-
import com.adt.service.UserManager; "J}B
lB
L4u.cHJ}0
/** 8"ZcK xDk
* @author Joa p!Tac%D+k
*/ }p)a7xn}
publicclass UserManagerImpl implements UserManager { yVPFH~1@\
WoSKN7*
private UserDAO userDAO; /d}5R@Oy
0&&P+adk
/** drwxrZt
* @param userDAO The userDAO to set. }+[!h=Bx
*/ ?"}U?m=
publicvoid setUserDAO(UserDAO userDAO){ 0,__{?!
this.userDAO = userDAO; wt_ae|hv
} ">fRM=fl
.OW5R*
/* (non-Javadoc) %.uN|o&n
* @see com.adt.service.UserManager#listUser Mj19;nc0I
#:MoZw`rlw
(org.flyware.util.page.Page) EjEXev<]
*/ mkBQTQGT
public Result listUser(Page page)throws :}SR{}]yXs
%hBw)3;l
HibernateException, ObjectNotFoundException { .'-t>(}v
int totalRecords = userDAO.getUserCount(); [a^<2V!vMn
if(totalRecords == 0) F?y
C=
throw new ObjectNotFoundException r|3u]rt
VWCC(YRU|$
("userNotExist"); K TE*Du
page = PageUtil.createPage(page, totalRecords); DuQ:82 3b
List users = userDAO.getUserByPage(page); X0$?$ta
returnnew Result(page, users); >Mm.MNU
} 3] U/^f3
aH500
} +$^[r
[R~@#I P!
M&/e*Ta5
hNp.%XnnZ
'@QK<!%,
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]<fZW"W<q
un,W{*s8*
询,接下来编写UserDAO的代码: 8h|~>v
3. UserDAO 和 UserDAOImpl: aJ]t1
java代码: ^#7&R"
q|
*nd!y'
]zvOM^l~
/*Created on 2005-7-15*/ Mw;^`ZxT
package com.adt.dao; (i@(ZG]/
t$Ua&w
import java.util.List; VOmS>'$
$@dPIq4o;}
import org.flyware.util.page.Page; U[@B63];0
;q<:iaY9
import net.sf.hibernate.HibernateException; Zk gj_
2+LvlS)C
/** Zl2doXC
* @author Joa "1ZVuI
*/ I?<ibLpX
publicinterface UserDAO extends BaseDAO { #Pq6q.UB
t 9.iWIr
publicList getUserByName(String name)throws I]d?F:cdX
:\1vy5 _
HibernateException; W5RZsS]
-dUXd<=ue
publicint getUserCount()throws HibernateException; @d[)i,d:G
XToYtdt2
publicList getUserByPage(Page page)throws <,nd]a
J8`vk#5
HibernateException; f%STkL)
LkXF~
} ??P>HVx
+$GP(Uu,
Bq85g5Dc
a'\fS7aE0l
"&kXAwe
java代码: q +c~Bd
Fw"x4w
dC">AW
/*Created on 2005-7-15*/ IBv9xP]BZ
package com.adt.dao.impl; nyd'79~>G
LoS%FI
import java.util.List; b=Q%Jxz?
YccD^w[`B
import org.flyware.util.page.Page; M5LqZyY
55x.Q
import net.sf.hibernate.HibernateException; k%cT 38V*
import net.sf.hibernate.Query; sVIw'W
\OF"hPq
import com.adt.dao.UserDAO; 2 wZyUB;
!2]G.|5/A
/** 9t0NO-a
* @author Joa n11eJEtm
*/ rEZMX2
public class UserDAOImpl extends BaseDAOHibernateImpl hKp-"
HBgt!D0MZ
implements UserDAO { MqswYK-s
Y<`uq'V
/* (non-Javadoc) mv9@Az9
* @see com.adt.dao.UserDAO#getUserByName q VJC O-K|
^G(+sb[t
(java.lang.String) a 1pa#WC
*/ }Xy<F?Mh
publicList getUserByName(String name)throws p4wXsOQ}
5A"OL6ty
HibernateException { ~FZ=
String querySentence = "FROM user in class U_Va'7
s$OnQc2/
com.adt.po.User WHERE user.name=:name"; 9m_Hm')VG
Query query = getSession().createQuery T$9tO{
x-s]3'!L
(querySentence); \RyW#[(
query.setParameter("name", name); QW}N,j$
return query.list(); 'd=B{7k@
} rc]`PV
.^*
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/* (non-Javadoc) OLxiY r
* @see com.adt.dao.UserDAO#getUserCount() *.NVc
*/ k:kx=K5=4
publicint getUserCount()throws HibernateException { Y+#VzIZw
int count = 0; _n_|skG
String querySentence = "SELECT count(*) FROM ZZ{:f+=?$
#a"gW,/K
user in class com.adt.po.User"; ,Tc598D
Query query = getSession().createQuery 5J8U] :Y)
Qa=v }d-O
(querySentence); gS4@3BOw&.
count = ((Integer)query.iterate().next veh?oJi@
*4F6U
()).intValue(); ;3WVrYe
return count; 8;]U:tv
} p_2-(n@
-XtDGNHF
/* (non-Javadoc) ,XNz.+Ov
* @see com.adt.dao.UserDAO#getUserByPage ue{0X\[P<
3 ]}wZY0
(org.flyware.util.page.Page) Kr|9??`0E
*/ Zb=H\#T
publicList getUserByPage(Page page)throws $@cg+Xrg1
.#y.:Pb|e
HibernateException { z>X<Di&x)
String querySentence = "FROM user in class 7nAB^~)6l
Z-,'M tD
com.adt.po.User"; %JC-%TRWK
Query query = getSession().createQuery %$L!N-U6
d@-bt s&3
(querySentence); 0(!D1G{ul
query.setFirstResult(page.getBeginIndex()) ;y"quJ'O
.setMaxResults(page.getEveryPage()); A296f(
return query.list(); 8 P=z"y
} N
v,Yikf
qkN{l88
} t LZ4<wc
&(Ot(.
m.A_u7D@
+WYXj
[vs5e3B)
至此,一个完整的分页程序完成。前台的只需要调用 `Al( AT(p
}&OgI