Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 NUO#[7OK+x
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 lJHU1
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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 .ZOG,h+8
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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 Y0z)5),[U:
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分页支持类: MnLo{G]
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java代码: ltWEA
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package com.javaeye.common.util; vRhI:E)So#
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import java.util.List; D6I-:{ws
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publicclass PaginationSupport { FOyANN'
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publicfinalstaticint PAGESIZE = 30; 7v']wA r]
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privateint pageSize = PAGESIZE; K' ?`'7
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privateList items; `w8Ejm?n
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privateint totalCount; a
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privateint[] indexes = newint[0]; m$.7) 24
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privateint startIndex = 0; <`V_H~Z
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public PaginationSupport(List items, int <@S'vcO
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totalCount){ $RA+StF!]
setPageSize(PAGESIZE); SpO%nZ";g8
setTotalCount(totalCount); 01n7ua*XX
setItems(items); f8?hEa:js
setStartIndex(0); eK[9wEdn
} iBPIj;,
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public PaginationSupport(List items, int 5_\1f|,
1rIL[(r4
totalCount, int startIndex){ GU0[K#%
setPageSize(PAGESIZE); w-"tA`F4
setTotalCount(totalCount); F05]6NVv
setItems(items); 6Z@?W
setStartIndex(startIndex); Eo`'6
3
} Bh UGMK
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public PaginationSupport(List items, int g [u*`]-;v
:bq${
totalCount, int pageSize, int startIndex){ r,<p#4(>_
setPageSize(pageSize); W5uC5C*,l
setTotalCount(totalCount); +<T361eyY
setItems(items); <CcSChCg
setStartIndex(startIndex); hRQw]
} v=_Ds<6n
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publicList getItems(){ cK- jN9U
return items; `.g'bZ<v/
} V
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publicvoid setItems(List items){ vX?C9Fr 2
this.items = items; 2"QcjFW%
} *`40B6dEr
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publicint getPageSize(){ lMmP]{.>$
return pageSize; 7/HX!y{WP
} 2c'<rkA
*&z!y/
publicvoid setPageSize(int pageSize){ RGLJaEl !
this.pageSize = pageSize; 7sU+:a
} qL?$u07<9'
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publicint getTotalCount(){ C1uV7t*\
return totalCount; t=\
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} -bgj<4R$p
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publicvoid setTotalCount(int totalCount){ y5j ;Daq
if(totalCount > 0){ ~J0r%P
this.totalCount = totalCount; t~|`RMn"
int count = totalCount / ?@^gpVK{
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pageSize; 6"9(ce
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if(totalCount % pageSize > 0) gSHN,8.
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count++; ,:{+-v(
indexes = newint[count]; ',1[rWyc
for(int i = 0; i < count; i++){ _4
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indexes = pageSize * Qoa&]]
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i; Uuktq)NU
} 50dx[v8
}else{ R"{P#U,HNO
this.totalCount = 0; $T_>WUiK
} +Mb}70^
} ( m7qc
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publicint[] getIndexes(){ N>iNz[a
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return indexes; jFl!<ooCo
} _=9m[
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publicvoid setIndexes(int[] indexes){ \"X_zM
this.indexes = indexes; @ %o'
} wkY$J\J
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publicint getStartIndex(){ HOr Xxxp1^
return startIndex; w}YcAnuB{%
} R1Fcd@DWD
/ <+F/R'=O
publicvoid setStartIndex(int startIndex){ }&]T0U`@
if(totalCount <= 0) tlYB'8bJY
this.startIndex = 0; N+vsQ!Qz
elseif(startIndex >= totalCount) W!|l_/L'
this.startIndex = indexes sT,*<^
";upu
[indexes.length - 1]; xg4wtfAbS
elseif(startIndex < 0) )Wk&c8|y
this.startIndex = 0; hbSKlb0d
else{ Of-8n-
this.startIndex = indexes 94?/Rhs5
h(i_'P?
[startIndex / pageSize]; S3Fj /2Q8
} s~A:*2 \
} F5+!Gb En
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publicint getNextIndex(){ [KMS/'; ]
int nextIndex = getStartIndex() + 9Qq%Fw_
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pageSize; "2:#bXM-
if(nextIndex >= totalCount) [7l5p(=
return getStartIndex(); N_p^DP
else 8\bZ?n#dn
return nextIndex; Gb.}af#v
} ^Yo2 R
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publicint getPreviousIndex(){ ?{~. }Vn
int previousIndex = getStartIndex() - =j@8/
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pageSize; [9Hrpo]tU:
if(previousIndex < 0) o}Zl/&(
return0; u"(2Xer
else p+;x&h)[l
return previousIndex; b(A;mt#N
} ^oEaE#I
||;a#FZ^
} ~Q)Dcit-
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抽象业务类 Bm;@}Ly=G
java代码: ):V)Hrq?x
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/** !/Wv\qm
* Created on 2005-7-12 CYNpbv
*/ KA."[dVa
package com.javaeye.common.business; +}C M2>M
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import java.io.Serializable; u73/#!(1=H
import java.util.List; V6b)
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import org.hibernate.Criteria; 2vW@d[<J
import org.hibernate.HibernateException; wQU-r|
import org.hibernate.Session; r]%.,i7~8
import org.hibernate.criterion.DetachedCriteria; '~7 6Y9mv
import org.hibernate.criterion.Projections; TzrU |D?
import yjucR
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org.springframework.orm.hibernate3.HibernateCallback; NmV][0(BS
import 9|hPl-.
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org.springframework.orm.hibernate3.support.HibernateDaoS {N0ky=ud
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upport; gC/-7/}
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import com.javaeye.common.util.PaginationSupport; ]K%D$x{+\
Ay\!ohIS3
public abstract class AbstractManager extends _1?Fyu&<5
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HibernateDaoSupport { #J4,mFMr
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privateboolean cacheQueries = false; C5oIl_t
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privateString queryCacheRegion; =Y5*J#
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publicvoid setCacheQueries(boolean Jm}zit:o
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cacheQueries){ Oxf,2r
this.cacheQueries = cacheQueries; h_h6@/1l
} }u'O<d~z?
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publicvoid setQueryCacheRegion(String DYCXzFAa
(9D,Ukw
queryCacheRegion){ 3yIC@>&y(8
this.queryCacheRegion = ,6a }l;lv
{%z}CTf#
queryCacheRegion; hH@pA:`s
} +yu^Z*_
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publicvoid save(finalObject entity){ .e2K\o
getHibernateTemplate().save(entity); ;?:X_C
} h2edA#bub
o8S)8_3
publicvoid persist(finalObject entity){ UjQi9ELoJ
getHibernateTemplate().save(entity); f5QJj<@
} g/m%A2M&aH
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publicvoid update(finalObject entity){ ]6EXaf#
getHibernateTemplate().update(entity); 4kQL\Ld#E%
} dDla?)F
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publicvoid delete(finalObject entity){ `=f1rXhI+1
getHibernateTemplate().delete(entity); '|N9xLm
} ^!>o5Y)
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publicObject load(finalClass entity, })}-K7v1+
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finalSerializable id){ :S
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return getHibernateTemplate().load K.jm>]'z4;
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(entity, id); ,b8q$R~\
} K|LS VN?K
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publicObject get(finalClass entity, e#$ZOK)`
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finalSerializable id){ s"\o6r
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return getHibernateTemplate().get BpKgUwf;C
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(entity, id); Qf]ACN
} SpUcrK;1
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publicList findAll(finalClass entity){ Px))O&w{
return getHibernateTemplate().find("from A">A@`}
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" + entity.getName()); :S5B3S@|
} D;al(q
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publicList findByNamedQuery(finalString jVpk) ;vC
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namedQuery){ 3 _tO
return getHibernateTemplate Kr]`.@/.S
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().findByNamedQuery(namedQuery); 5:H9B
} ?pv}~>
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publicList findByNamedQuery(finalString query, T9+ ?A
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finalObject parameter){ [UHDN:y
return getHibernateTemplate cHMS[.=;
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().findByNamedQuery(query, parameter); Y@Kp'+t(!
} m,U`hPJ
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publicList findByNamedQuery(finalString query, *tda_B
2
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finalObject[] parameters){ fH7o,U|
return getHibernateTemplate @E$PjdB5M
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().findByNamedQuery(query, parameters); qe:,%a-9
} mSzBNvci
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publicList find(finalString query){ $Q|t^(
return getHibernateTemplate().find ?q<"!U|e
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(query); dSb|hA}@
} ?b~V uo
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publicList find(finalString query, finalObject ]64mSB
*_z5Pa`A
parameter){ NVMhbpX6
return getHibernateTemplate().find rnVh
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h*Y);mc$#
(query, parameter); TK;*:K8oe
} T}X#I'Z
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public PaginationSupport findPageByCriteria %Y` @>P'
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(final DetachedCriteria detachedCriteria){ n@xDFa
return findPageByCriteria j#b?P=|l
sgo({zA`i
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 'Z+~G
} !0~$u3[b
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public PaginationSupport findPageByCriteria e1X*}OI
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(final DetachedCriteria detachedCriteria, finalint }06
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startIndex){ Qc z7IA
return findPageByCriteria Poacd;*
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(detachedCriteria, PaginationSupport.PAGESIZE, Dm6}$v'0
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startIndex); .Mw'P\GtM
} b$nXljV4?
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public PaginationSupport findPageByCriteria 4XDR?KUM
9
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(final DetachedCriteria detachedCriteria, finalint 2@o_7w98
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pageSize, dvk?A$
finalint startIndex){ oQ 5g0(J~
return(PaginationSupport) *tjE#TW
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getHibernateTemplate().execute(new HibernateCallback(){ Xz0jjO,
publicObject doInHibernate 0CxQ@~ttl
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(Session session)throws HibernateException { d^IOB|6Q
Criteria criteria = :Q sGwhB
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detachedCriteria.getExecutableCriteria(session); hq/\'Z&!+P
int totalCount = pK#Ze/!
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((Integer) criteria.setProjection(Projections.rowCount hNXPm~OK\
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()).uniqueResult()).intValue(); f8)D|
criteria.setProjection b1jh2pG(V
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(null); .
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List items = #JGy2Hk$^
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criteria.setFirstResult(startIndex).setMaxResults abUn{X+f~
(
=->rP
(pageSize).list(); wYhWRgP
PaginationSupport ps = y>u+.z a|
gy _86y@
new PaginationSupport(items, totalCount, pageSize, ~-Rr[O=E
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8
startIndex); _h7+.U=
return ps; dZRz'd
} f
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}, true); ,-t3gc1~X
} J
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public List findAllByCriteria(final <FMW%4
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DetachedCriteria detachedCriteria){ nbw&+dcJ8
return(List) getHibernateTemplate i)\`"&.j>N
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().execute(new HibernateCallback(){ O%A:2Y79
publicObject doInHibernate \CB{Ut+s
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(Session session)throws HibernateException { oDx*}[/
Criteria criteria = +GgWd=X.Y
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detachedCriteria.getExecutableCriteria(session); BXaA#} ;e
return criteria.list(); QR'"Zw&q5/
} hyL3fkMJ,
}, true); }.4`zK&SB
} KSuP'.l
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public int getCountByCriteria(final _$0<]O$
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DetachedCriteria detachedCriteria){ D*`|MzlQ
Integer count = (Integer) ;or(:Yoc-
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getHibernateTemplate().execute(new HibernateCallback(){ 1okL]VrI
publicObject doInHibernate abWmPi
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(Session session)throws HibernateException { oGly|L>
Criteria criteria = ,y3o ,gl
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detachedCriteria.getExecutableCriteria(session); vAq`*]W+
return $uawQf+S
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criteria.setProjection(Projections.rowCount `.Y["f
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()).uniqueResult(); 7<AHQ<#@
} [L|H1ll
}, true); AGn:I??
return count.intValue(); LCRreIIgZ
} 5P
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} WDSkk"#TF
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用户在web层构造查询条件detachedCriteria,和可选的 :+/V
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 #SQT!4
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PaginationSupport的实例ps。 -wC;pA#o
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ps.getItems()得到已分页好的结果集 '[~NRKQJ
ps.getIndexes()得到分页索引的数组 utQE$0F
ps.getTotalCount()得到总结果数 nE+sbfC
ps.getStartIndex()当前分页索引 *pk*ijdB
ps.getNextIndex()下一页索引 Q{UR3U'Q
ps.getPreviousIndex()上一页索引 @ _U]U
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 *O#%hTYq
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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 \kvd;T#t6
rm;'/l8Y-E
一下代码重构了。 VThcG(
NF
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我把原本我的做法也提供出来供大家讨论吧: L|qQZ=
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首先,为了实现分页查询,我封装了一个Page类: gV):3mWC
java代码: :mXc|W3
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/*Created on 2005-4-14*/ ~urIA/
package org.flyware.util.page; 2 #kR1rJP
dd@^e)VZB
/** D*o_IrG_(
* @author Joa Q`4=
* f/~"_O%
*/ YxlV2hcX;
publicclass Page { EQSOEf[
,@tkL!"9q
/** imply if the page has previous page */ 5:Pp62
privateboolean hasPrePage; <h4"^9hL
$]%;u: Sa
/** imply if the page has next page */ 8s/gjEwA
privateboolean hasNextPage; r )ZUeHt}w
}Xr-xh\v
/** the number of every page */ Y|_#yb
privateint everyPage; MGfDxHg]
@HxEp;*NH"
/** the total page number */ P(_D%0xKm
privateint totalPage; &dh%sFy
=dHM)OXD"
/** the number of current page */ d=o|)kV
privateint currentPage; 7cr@;%#
V8ZE(0&II}
/** the begin index of the records by the current wdS^`nz|
);_g2=:#
query */ {(w/_C9
privateint beginIndex; =${]j
h$)(-_c3
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/** The default constructor */ G+stt(k:
public Page(){ mM!'~{r[-
jGl8y!aM
} U s86.@|
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/** construct the page by everyPage f_}/JF
* @param everyPage ];Z)=y,vM
* */ <gF=$u|}3[
public Page(int everyPage){ P9p:x6
this.everyPage = everyPage; SUINV_>7
} _G|hKk^,
K 4QJDC8
/** The whole constructor */ HYyO/U9z|I
public Page(boolean hasPrePage, boolean hasNextPage, p~6/+ap
8W#/=Xh?
?:vp3f#
int everyPage, int totalPage, 9un]}7^
int currentPage, int beginIndex){ z}.y
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this.hasPrePage = hasPrePage; j5,1`7\7B
this.hasNextPage = hasNextPage; B8UtD
this.everyPage = everyPage; veAg?N<c
p
this.totalPage = totalPage; C8rD54A'M
this.currentPage = currentPage; I|9(*tq)
this.beginIndex = beginIndex; HS XS%v/Y
} f]`#BE)V
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/** ^q5~;_z|
* @return 3('=+d[}Vw
* Returns the beginIndex. px %xoY
*/ 26PUO$&b.
publicint getBeginIndex(){ X1&Ug^
return beginIndex; Qz\yoI8JA,
} 8]skAh
[bk2RaX:i
/** ^u&oS1U
* @param beginIndex oW(lQ'"
* The beginIndex to set. #no~g(!o
*/ Zt4g G KG
publicvoid setBeginIndex(int beginIndex){ qYR
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this.beginIndex = beginIndex; Se<]g$eK?5
} "[2CV!_
l*>t@:2J
/** (|)`~z
* @return c[\ :^w^I6
* Returns the currentPage. 4YDK`:4I~
*/ ~XN--4%Q
publicint getCurrentPage(){ =}>wxO
return currentPage; x=T`i-M
} _;(`u!@/{
J ^gtSn^
/** HM57b>6
* @param currentPage 1+6:K._C(m
* The currentPage to set. JTK>[|c9oE
*/ *p:`F:
publicvoid setCurrentPage(int currentPage){ .Uq?SmK
this.currentPage = currentPage; b~X^vXIv%%
} e8g"QDc
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/** `Fa49B|`D
* @return gwhd) .*
* Returns the everyPage. 1{l18B`
*/ Ri4t/H
publicint getEveryPage(){ kR$>G2$!
return everyPage; Wt5x*p-!C
} 0zm)MSg
R)i
/** y6NOHPp@
* @param everyPage ie|I*;#
* The everyPage to set. fHhm)T8KB
*/ Atl`J.;G
publicvoid setEveryPage(int everyPage){ :W]?6=
this.everyPage = everyPage; aEU[k>&
} ]@X5'r"
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/** e~R;
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* @return .{sKEVK
* Returns the hasNextPage. KilgeN:
*/ CvfXm
publicboolean getHasNextPage(){ >2h|$6iWP
return hasNextPage; X8~dFjhX
} *uHL'Pe;m
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/** ,:g.B\'Q
* @param hasNextPage $$ %4,\{l
* The hasNextPage to set. y_O [r1MF
*/ 5tPBTS<<"L
publicvoid setHasNextPage(boolean hasNextPage){ K$OxeJP?F
this.hasNextPage = hasNextPage; -c-af%xD
} =|>CB
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/** [-o`^;
* @return Gr9/@U+
* Returns the hasPrePage. vSty.:bY\p
*/ X"WKgC g$
publicboolean getHasPrePage(){ T=r-6eN
return hasPrePage; r=GF*i[3
} Q#C;4)e
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/** HT]W2^k
* @param hasPrePage H`u8}{7
* The hasPrePage to set. ,M2u (9
*/ A4LGF
publicvoid setHasPrePage(boolean hasPrePage){ Z$qFjWp
this.hasPrePage = hasPrePage; 3t<XbHF9
} U'^AJ2L8
+5J "G/f
/** 'J^ M`/
* @return Returns the totalPage. <$\vL
* s ^NO(
*/ mF!/8qk
publicint getTotalPage(){ [ZwZGAP
return totalPage; yMdEH-?/
} `$og]Dn;
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/** iVq4&X_x
* @param totalPage @L^Fz$Sx
* The totalPage to set. .d<
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*/ <viIpz2jh%
publicvoid setTotalPage(int totalPage){ u@|izRk
this.totalPage = totalPage; aE}1~`
} u\YH,
V|=PaO
} B$~oZ'4v
'[#a-8-JY_
~3}Gu^@
}~P%S(zB
fDc>E+,
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 [8*Ovd
cBf9-k
个PageUtil,负责对Page对象进行构造: ;t!n%SnK9!
java代码: ,h21 h?6
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qW]gp7jK4
/*Created on 2005-4-14*/ >)ZX
package org.flyware.util.page; =`2nv0%2
CU=}]Y
import org.apache.commons.logging.Log; +EJwWDJ!%
import org.apache.commons.logging.LogFactory; +|.}oL^}G
!_GY\@}
/** 4)D#kP
* @author Joa mhnjYK9
* PfX{n5yBW8
*/ hW*2Le!I
publicclass PageUtil { [% chN/
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privatestaticfinal Log logger = LogFactory.getLog "=4`RM
HZMs],GX
(PageUtil.class); QX(x6y>Q
$>E\3npV
/** "bZV<;y6
* Use the origin page to create a new page \8\)5#?
* @param page f.V;Hl,
* @param totalRecords qh
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* @return V~LZ%NZ8
*/ YArNJ5z=
publicstatic Page createPage(Page page, int 1|Y(XB^os(
8f>=.O*)
totalRecords){ }qfr&Ffh@
return createPage(page.getEveryPage(), 8Ml&lfn_8
'Z2:u!E
page.getCurrentPage(), totalRecords); r})2-3ZA9
} gA
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mhTpR0
/** h}xUZ:
* the basic page utils not including exception #1R_*
Uh
}aYm86C]
handler 9@AGx<S1
* @param everyPage MhC74G
* @param currentPage
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* @param totalRecords xw: v|(
* @return page >yvP[$]!6
*/ !mFo:nQ)}
publicstatic Page createPage(int everyPage, int Rf@D]+v
;SQ<^"eK
currentPage, int totalRecords){ Wd4fIegk
everyPage = getEveryPage(everyPage); L/(e/Jalg
currentPage = getCurrentPage(currentPage); ,CW]d#P|
int beginIndex = getBeginIndex(everyPage, zi:F/TlUC
bb;fV
currentPage); mY-Z$8r
int totalPage = getTotalPage(everyPage, KtJE
ZWMX!>o<
totalRecords); WrbDB-uM
boolean hasNextPage = hasNextPage(currentPage, O;M_?^'W
RAKQ+Y"nl
totalPage); ANSv ZqKh
boolean hasPrePage = hasPrePage(currentPage); 9[DQ[bL
sBuJK'
returnnew Page(hasPrePage, hasNextPage, mOwgk7s[J
everyPage, totalPage, Wm:3_C +j
currentPage, Pb?H cg
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beginIndex); >`*iM
} 7ka^y k@Q
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privatestaticint getEveryPage(int everyPage){ ))c;DJc
return everyPage == 0 ? 10 : everyPage; lp[3z&u
} ub6\m=Y7
($(6]?J(?7
privatestaticint getCurrentPage(int currentPage){ T(+F6d=1
return currentPage == 0 ? 1 : currentPage; qGkrG38K
} ~C5iyXR
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privatestaticint getBeginIndex(int everyPage, int n ! qm
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currentPage){ Lhl)p P17
return(currentPage - 1) * everyPage; Bir}X
} Wy#`*h,
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privatestaticint getTotalPage(int everyPage, int hgj#VY$B
j>&n5?
totalRecords){ [2w3c4K
int totalPage = 0; y- k?_$M
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if(totalRecords % everyPage == 0) WAY<X:|We
totalPage = totalRecords / everyPage; &ukNzV}VW
else GQqw(2Ub}
totalPage = totalRecords / everyPage + 1 ; *p?b "{_a
q`1t*<sk
return totalPage; 7qE V5!
} qNHS 1
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privatestaticboolean hasPrePage(int currentPage){ =\4w" /Y
return currentPage == 1 ? false : true; 7 g ]]>
} ulfpop*2
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privatestaticboolean hasNextPage(int currentPage, S
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int totalPage){ ]+0-$t7Y
return currentPage == totalPage || totalPage == m?<8 ':
R
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0 ? false : true; 3FPy"[[
} &Wd,l$P<O
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} ORQGay
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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。 ZfT%EPoZ:
5YS`v#+
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 \(T;@r
5[l3]HOO
做法如下: 1+eC'&@Xjt
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 -D:J$d
6R<
W}L=JJo},
的信息,和一个结果集List: eE7Rd>
java代码: 5B'-&.Aj+
%c^]Rdl
h>mQ; L
/*Created on 2005-6-13*/ A!^K:S:@
package com.adt.bo; /bCrpcH
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import java.util.List; &tMvs<q,
@1n0<V/
import org.flyware.util.page.Page; 1<\cMY6
p00\C
/** Rp`}"x9
* @author Joa +Yi=Wo/
*/ oeIB1DaI
publicclass Result { XQj`KUO@
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private Page page; DP;B*s4{U
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private List content; 2gt08\
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/** FC]? T
* The default constructor 8(3vNuyP
*/ xmiF!R
public Result(){ R63"j\0
super(); Y}1|/6eJ
} &OI=rvDmo
{ +C>^b
/** ]-* }-j`
* The constructor using fields 1M3U)U
* dDpe$N
* @param page |AFF*]e S
* @param content ^S<Z'S
*/ /o|@]SAe.
public Result(Page page, List content){ ).ugMuk
this.page = page; sXhtn'<v
this.content = content; +,|-4U@dl
} -q+Fj;El
/AMtT%91
/** PKjA@+
* @return Returns the content. iicrRGp3
*/ 9 l,Gd
publicList getContent(){ p^L6uM
return content; qbP[ 9
} vxqMo9T
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/** ;Rnb^t6Z
* @return Returns the page. '|]zBpz
*/ |fw+{f
public Page getPage(){ 5n9F\T5
return page; sWX
} %<
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l
/** CiMy_`H
* @param content ]AHUo;(f%
* The content to set. J| 'T2g
*/ o1n c.2/0J
public void setContent(List content){ _puQX@i
this.content = content; gsU&}R1*h
} *g=*}2
=r_ SMTu
/** Mb<KZ_wYOX
* @param page QPFpGS{d
* The page to set. !4 hs9b
*/ @x=CMF15
publicvoid setPage(Page page){ wPc,FH+y
this.page = page; Zy!\=-dSm
} ~Yr.0i.W
} (>8fcQUBb
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@ym7hk.
SA/0Z =
2. 编写业务逻辑接口,并实现它(UserManager, ,U2D&{@
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UserManagerImpl) F(XWnfUv
java代码: ,U7hzBj8k
`nizGg~1
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/*Created on 2005-7-15*/ R 7{r Y
package com.adt.service; :ZzG5[o3
O!j@8~='
import net.sf.hibernate.HibernateException; p[/n[@<8=
BFEo:!'F
import org.flyware.util.page.Page; NKB!_R+
HFDg@@
import com.adt.bo.Result; ]3I_H+hU
N9*$'
/** tP:xx2N_
* @author Joa RV($G8U
*/ k[zf`x^
publicinterface UserManager { ?.Kl/8ml
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public Result listUser(Page page)throws t6"4+:c!>
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HibernateException; }YSH8d
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} PAc~p8S
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/0\pPc*kA{
(&gCVf
java代码: !l\pwfXP&%
UbYKiLDF)
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/*Created on 2005-7-15*/ :5Vu.\,1
package com.adt.service.impl; s e1ipn_A
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import java.util.List; ?Z!KV=
sV+>(c-$
import net.sf.hibernate.HibernateException; *o>E{
B#gmT2L
import org.flyware.util.page.Page; es6e-y@e
import org.flyware.util.page.PageUtil; pE`(kD
\UC4ai2MK
import com.adt.bo.Result; 1rKR=To
import com.adt.dao.UserDAO; D{4
Y:O&J
import com.adt.exception.ObjectNotFoundException; e-s@@k
import com.adt.service.UserManager; vx4&
;2
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/**
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* @author Joa 6%'{Cq1DE
*/ %sq=lW5R{b
publicclass UserManagerImpl implements UserManager { K)v(Z"
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private UserDAO userDAO; 4 '+)9&g
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/** $K iMu
* @param userDAO The userDAO to set. 7]^Cg;EtM:
*/ *\`C!r
publicvoid setUserDAO(UserDAO userDAO){ jsG9{/Ov3
this.userDAO = userDAO;
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} _m&VdIPO
zZRqb/20
/* (non-Javadoc) ysa"f+/
* @see com.adt.service.UserManager#listUser 6RF01z|~_
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(org.flyware.util.page.Page) e}?t[aK4#
*/ ~\/ J&
public Result listUser(Page page)throws y#MLxm
a=J?[qrx
HibernateException, ObjectNotFoundException { 0N}5sF
int totalRecords = userDAO.getUserCount(); s,}<5N]U
if(totalRecords == 0) sDF J
throw new ObjectNotFoundException YU"Am !
226s:\d
("userNotExist"); \x+DEy'4;5
page = PageUtil.createPage(page, totalRecords); @<2pYIi8
List users = userDAO.getUserByPage(page); *p-Fn$7\n
returnnew Result(page, users); }Q%>Fv
} L=p.@VSZ
kal8k-$#
} s=$ 7lYX
CxRp$;rk
M{S7ia"s
OBZ |W**N"
/X:lt^?%I
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 XX F9oy8
,'9tR&S$_
询,接下来编写UserDAO的代码: a_ P[J8j
3. UserDAO 和 UserDAOImpl: ! $iR:ji
java代码: Y}Dp{
DYl^6]
dbLX}>
/*Created on 2005-7-15*/ 3UaP7p+d
package com.adt.dao; Z 0:2x(x9
JTI m`t"d=
import java.util.List; .
9
NS
q!,do2T
import org.flyware.util.page.Page; OBl8kH(b>
ZMe| fn
import net.sf.hibernate.HibernateException; 3 x'30
X+3)DE\2
/** ) &9=)G
* @author Joa sV6A&