Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 C `6S}f,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 T
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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 oqYt/4^Q
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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 A?r^V2+j
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分页支持类: bcn7,ht
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java代码: #q;z8 @
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package com.javaeye.common.util; (hN?:q?'
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import java.util.List; Ha218Hy0W
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publicclass PaginationSupport { `XgFga)
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publicfinalstaticint PAGESIZE = 30; ?-,6<K1
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privateint pageSize = PAGESIZE; \c%g M1
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privateList items; hl]S'yr
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privateint totalCount; V%51k{
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privateint[] indexes = newint[0]; T,OS 0;7O
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privateint startIndex = 0; RG1\=J$:E
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public PaginationSupport(List items, int w.^yP7:
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totalCount){ ``4?a7!!
setPageSize(PAGESIZE); 4.w"(v9 V
setTotalCount(totalCount); MUwxgAG`G
setItems(items); J|5Ay1eF-
setStartIndex(0); dB7ZT0L\
} F 7LiG9H6`
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public PaginationSupport(List items, int v2>Z^
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totalCount, int startIndex){ niz 'b]] +
setPageSize(PAGESIZE); wE6A
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setTotalCount(totalCount); 328L)BmW
setItems(items); V|: qow:F
setStartIndex(startIndex); Z&Pu8zG
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} lDN?|YG
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public PaginationSupport(List items, int D/:3RZF
no&-YktP}
totalCount, int pageSize, int startIndex){ YtYy zX5u7
setPageSize(pageSize); P=gJAE5
setTotalCount(totalCount); _ZyT3P&
setItems(items); u"Y]P*[k
setStartIndex(startIndex); Nfaf;;J}
} [K:29N9~4
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publicList getItems(){ N|Habua<Xw
return items; DFy1 bg
} !_x*m@/
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publicvoid setItems(List items){ Nog(VN4I&
this.items = items; zPE$
} x{hn2]6+eB
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publicint getPageSize(){ ~ffwLgu!
return pageSize; Mudrg[@`
} JA6";fl;
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publicvoid setPageSize(int pageSize){ IU9,
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this.pageSize = pageSize; "+h/-2rA
} E9$H nj+m
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publicint getTotalCount(){ C6^j#rl
return totalCount; 5[R?iSGL1
} l$M +.GB<
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publicvoid setTotalCount(int totalCount){ "8/dD]=f^a
if(totalCount > 0){ m~>@BCn;
this.totalCount = totalCount; [W;[v<E;
int count = totalCount / ^yVl"/
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pageSize; -J?~U2
if(totalCount % pageSize > 0) iN)af5)[^
count++; Y/lN@
indexes = newint[count]; c-*2dV[@
for(int i = 0; i < count; i++){ 6+PGwCS
indexes = pageSize * 9o_-=>(
7' eh)[T
i; u-.L^!k
} '[fZt#
}else{ ~L'nzquF
this.totalCount = 0; (("OYj
} z_l. V/G)
} 'n4u-pM(nB
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publicint[] getIndexes(){ &J(!8y*QyE
return indexes; v3-?CQb(
} I%xn,u
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publicvoid setIndexes(int[] indexes){ UvBnf+,
this.indexes = indexes; ug&92Hdvy3
} ny1 \4C
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publicint getStartIndex(){ ~ 5"J(
return startIndex; [@2s&Ct;
} _9kIRmT{
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publicvoid setStartIndex(int startIndex){ D9o*8h2$
if(totalCount <= 0) KB+]eI-h
this.startIndex = 0; m&Sp1=*Ejy
elseif(startIndex >= totalCount) /aOlYqM(>
this.startIndex = indexes C +@ i
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[indexes.length - 1]; !<r8~A3!(
elseif(startIndex < 0) [H^ X"D
this.startIndex = 0; _}ele+
else{ d?7BxYaa
this.startIndex = indexes V(..8}LlD
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[startIndex / pageSize]; x6e +7"#~
} %U?)?iZdL
} 7\%$>< K
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publicint getNextIndex(){ ) 4ncutb
int nextIndex = getStartIndex() + CZ tiWZ
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pageSize; n7DLJ`ho{
if(nextIndex >= totalCount) 2AK}D%jfc
return getStartIndex(); #r}uin*jD
else =v0~[E4
return nextIndex; xb`CdtG2.
} o4~kX
or.\)(m#(
publicint getPreviousIndex(){ 5^2TfG9
int previousIndex = getStartIndex() - bQ.nFa']
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pageSize; Ja [#[BJ?
if(previousIndex < 0) X6kaL3L}
return0; |Puj7Ru
else u+z~
return previousIndex; =|V"#3$f
} jY+Do:#/wO
4 J8Dh;a`
} Cuv|6t75'
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抽象业务类 26PD[af64O
java代码: [*HiI=
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/** "dq>)JF\
* Created on 2005-7-12 ]_#SAhOR)
*/ gh61H:t kR
package com.javaeye.common.business; ^A#x<J+
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import java.io.Serializable; ]-Lruq#
import java.util.List; U8[Qw}T P
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import org.hibernate.Criteria; mATH*[Y
import org.hibernate.HibernateException; R@$+t:}
import org.hibernate.Session; k=|K|
import org.hibernate.criterion.DetachedCriteria; r=\P!`{5
import org.hibernate.criterion.Projections; `oXg<tivU
import t=
*Jg/$
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org.springframework.orm.hibernate3.HibernateCallback; y/\ZAtnLo
import ;sQ20 B'
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org.springframework.orm.hibernate3.support.HibernateDaoS _yJ|`g]U3
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upport; )Y[/!
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import com.javaeye.common.util.PaginationSupport; CjV7q y
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public abstract class AbstractManager extends niAZ$w
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HibernateDaoSupport { c/RT0xql*
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privateboolean cacheQueries = false; Gym#b{#":
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privateString queryCacheRegion; 9C=~1>S
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publicvoid setCacheQueries(boolean QA,*:qx
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cacheQueries){ Hh\
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this.cacheQueries = cacheQueries; QH:>jmC{1h
} cqjl5UB
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publicvoid setQueryCacheRegion(String Rv,Mu3\~#c
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queryCacheRegion){ SdSgn |S
this.queryCacheRegion = bq: [Nj
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queryCacheRegion; I}_;A<U
} /} a_8iM\
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publicvoid save(finalObject entity){ 1wlVz#f.
getHibernateTemplate().save(entity); ?61L|vr
} ka8$dfC
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publicvoid persist(finalObject entity){ IqXBz.p
getHibernateTemplate().save(entity); Fr2kbQTg;
} hd8B0eD'
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publicvoid update(finalObject entity){ "R8.P/ 3
getHibernateTemplate().update(entity);
}Zt.*%
} R)Q/Ff@o0
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publicvoid delete(finalObject entity){ fw:7U%MGv
getHibernateTemplate().delete(entity); |SxMN%M!
} },v&rkwR
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publicObject load(finalClass entity, V&g)m.d:n
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finalSerializable id){ D/cg7
return getHibernateTemplate().load FN>L7
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(entity, id); m[W/j/$A+x
} N6WPTUQ1mF
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publicObject get(finalClass entity, )O9f hj)
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finalSerializable id){ ygMd$0:MN
return getHibernateTemplate().get
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(entity, id); *!i,?vn
} JV&Zwbu
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publicList findAll(finalClass entity){ K[e`t%2_
return getHibernateTemplate().find("from xUIvLH=
gt~9"I
" + entity.getName()); LNaeB(z"
} @`5QG2
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publicList findByNamedQuery(finalString y2GQN:X
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namedQuery){ ?vMK'"
return getHibernateTemplate p?}f|mQS)
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().findByNamedQuery(namedQuery); g
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} QjI#Cs}w
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publicList findByNamedQuery(finalString query, l},dQ4R
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finalObject parameter){ Wux 0RF&
return getHibernateTemplate zaH
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().findByNamedQuery(query, parameter); 9U&~(;
} o1Ne+Jt
=[ s8q2V
publicList findByNamedQuery(finalString query, ix:2Z-
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finalObject[] parameters){ XMomFW_@
return getHibernateTemplate KuIkul9^%
3'.!
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().findByNamedQuery(query, parameters); HJc<Gwm
} Sw yaYK
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publicList find(finalString query){ L^6"'#
return getHibernateTemplate().find O5ucI$s
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(query); I+*osk
} >ze>Xr'm5=
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publicList find(finalString query, finalObject xT:qe
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parameter){ Rk}\)r\
return getHibernateTemplate().find iK ohuZr
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(query, parameter); p 7
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} x6"/z
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public PaginationSupport findPageByCriteria GVeL~Q
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(final DetachedCriteria detachedCriteria){ -)p@BtMS
return findPageByCriteria >Dk1axZ!>/
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^
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Jw2B&)k/
} )ZQHa7V
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public PaginationSupport findPageByCriteria Cq-hPa}2
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(final DetachedCriteria detachedCriteria, finalint Lc58lV=
nUiS<D2
startIndex){ 8w03{H
0
return findPageByCriteria O5g}2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0PYvey }[
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startIndex); _2NN1/F5
} ,.~
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public PaginationSupport findPageByCriteria sGXp}{E9
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(final DetachedCriteria detachedCriteria, finalint &r&;<Q
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pageSize, b\kN_
finalint startIndex){ );0<Odw%.
return(PaginationSupport) GwTT+
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getHibernateTemplate().execute(new HibernateCallback(){ {
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publicObject doInHibernate Hlz'a1\:O]
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(Session session)throws HibernateException { Q2JdO 6[96
Criteria criteria = pYYqGv^oa
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detachedCriteria.getExecutableCriteria(session); -Aym+N9
int totalCount = 8JO\%DFJ
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((Integer) criteria.setProjection(Projections.rowCount nz?BLO=
C%o/
()).uniqueResult()).intValue(); KZ/^gR\d
criteria.setProjection EsxTBg
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(null); 3bL2fsn5
List items = WoG
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criteria.setFirstResult(startIndex).setMaxResults 9d(v^T
SSM>
ID
(pageSize).list(); eS%6hUb
PaginationSupport ps = "ZB`fNE
..{^"`FQ
new PaginationSupport(items, totalCount, pageSize, ^aM/BS\
*8eh%3_$h
startIndex); 1ZW'PXUZ
return ps; m<LzB_G\
} :<3;7R'5
}, true); $zA[5}{ZtQ
} 90696v.
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public List findAllByCriteria(final f!Nc+
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DetachedCriteria detachedCriteria){ <;Z~ vZ]
return(List) getHibernateTemplate -ns a3P
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L
().execute(new HibernateCallback(){ Fm~}A4
publicObject doInHibernate g#nsA(_L
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(Session session)throws HibernateException { 2Sd6b 2-
Criteria criteria = &`y_R'
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detachedCriteria.getExecutableCriteria(session); 1ucUnNkcV
return criteria.list(); U1tPw`0h
} f5XcBW9E
}, true); {$=%5
} BqA wo
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public int getCountByCriteria(final bGnJ4R3J
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DetachedCriteria detachedCriteria){ j`M<M[C*4N
Integer count = (Integer) BnY|t2r
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getHibernateTemplate().execute(new HibernateCallback(){ c`=hK*
publicObject doInHibernate 3/<^R}w\
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(Session session)throws HibernateException { ?^GsR[-x
Criteria criteria = -+Ji~;b
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detachedCriteria.getExecutableCriteria(session); GB Un" _J
return ?Og ;W9i
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criteria.setProjection(Projections.rowCount !Bbwl-e`
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()).uniqueResult(); bvvx(?!
} 2;7GgO~
}, true); S(s~4(o>8
return count.intValue(); wWswuhq<
} O@&I.d$
} tELnq#<6
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用户在web层构造查询条件detachedCriteria,和可选的 !.N=Y;@lY
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 c=E.-
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PaginationSupport的实例ps。 FJ.
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ps.getItems()得到已分页好的结果集 LM`#S/h
ps.getIndexes()得到分页索引的数组 1#RA+d(
ps.getTotalCount()得到总结果数 [$+61n}.12
ps.getStartIndex()当前分页索引 ho<#i(
ps.getNextIndex()下一页索引 nXW1 :
ps.getPreviousIndex()上一页索引 !9Xex?et
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 .6(i5K
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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
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一下代码重构了。 |%9~W^b
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我把原本我的做法也提供出来供大家讨论吧: $o^}<)DW
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首先,为了实现分页查询,我封装了一个Page类: L1+cv;t
java代码: F.hC%Ncu
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/*Created on 2005-4-14*/ pc>R|~J{2
package org.flyware.util.page; M](U"K?
r73Xh"SL
/** t?Znil|o
* @author Joa ymqhI\>y#
* s#sXr
*/ Fv
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publicclass Page { IRY2H#:$
'?4[w]0J<
/** imply if the page has previous page */ nQC[[G*x
privateboolean hasPrePage; o!d0
rkp0ej2-
/** imply if the page has next page */ fA5#
2P{
privateboolean hasNextPage; %vzpp\t
jws(`mIf\
/** the number of every page */ 1uE[ %M
privateint everyPage; }zi6 F.
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/** the total page number */ u[@*}|uXM
privateint totalPage; % *hBrjbj
B dUyI_Ks:
/** the number of current page */ 6<R
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privateint currentPage; &kt#p;/p?
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/** the begin index of the records by the current R/7l2 *
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query */ &v88xs
privateint beginIndex; b1"wQM9
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/** The default constructor */ t@v8>J%K
public Page(){ ;!b(b%
FeJ5^Gh.
} 9EW 7,m{A
L M[<?`%p
/** construct the page by everyPage VB%xV
* @param everyPage u^$ CR
* */ %8/$CR
public Page(int everyPage){ x(Z@R\C-a
this.everyPage = everyPage;
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} 3m'6 cMQ
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/** The whole constructor */ G<I5%Yo6G
public Page(boolean hasPrePage, boolean hasNextPage,
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int everyPage, int totalPage, }#1{GhsS
int currentPage, int beginIndex){ Q*5d~Yr ]R
this.hasPrePage = hasPrePage; |k0VJi
this.hasNextPage = hasNextPage; V^D#i(5
this.everyPage = everyPage; VrG |/2
this.totalPage = totalPage; !.A>)+AK
this.currentPage = currentPage; g$qh(Z_s
this.beginIndex = beginIndex; nK[$ID
} - =Hr|AhE
)/Vr 5b@
/** a &j?"o
* @return 'AoH2 |
* Returns the beginIndex. >=(e}~5y
*/ +oa]v1/W
publicint getBeginIndex(){ &DV'%h>i=
return beginIndex; 9cQSS'`F
} {rDZKy^f
uo^>95lkv
/** d>}%A
]
* @param beginIndex 4C$,X!kzF
* The beginIndex to set. >X]<s^
*/ s?G@k} {
publicvoid setBeginIndex(int beginIndex){ , /pE*Yk
this.beginIndex = beginIndex; /:DxB00
} b< rM3P;
\]D;HR`vo
/** e-WaK0Ep
* @return !}%giF$-
* Returns the currentPage. [
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*/ Ptg73Gm&R
publicint getCurrentPage(){ 'nul{RE*
return currentPage; UkC\[$-"\
} #rC% \
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/** 2;3q](d
* @param currentPage =[$*PTe
* The currentPage to set. JmK+#o
*/ kF5}S8B
publicvoid setCurrentPage(int currentPage){ xiiZ'U
this.currentPage = currentPage; p ,!`8c6
} ;Mc}If*
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/** CfAqMH*ip
* @return 0t~--/lA
* Returns the everyPage. tP UQ"S
*/ qy!G&
publicint getEveryPage(){ l/]P6 @N
return everyPage; Kfi A 7W
} -%A6eRShk
&&JMw6
&[`
/** <:p&P
* @param everyPage {"<Q?yA2y
* The everyPage to set. CNwhH)*
*/ 5segzaI
publicvoid setEveryPage(int everyPage){ )gR&Ms4
this.everyPage = everyPage; $KiA~l
} {|fA{ Q_R
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/** q&+GpR
* @return 6*e:ey U
* Returns the hasNextPage. 7J_H Ox#
*/ k$hWR;U
publicboolean getHasNextPage(){ |^=`ln!
return hasNextPage; </fnbyGR
} w-KtxG(
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/** _CgD7d
* @param hasNextPage $6_J`7
* The hasNextPage to set. \6N\6=t!A
*/ bx@CzXre;
publicvoid setHasNextPage(boolean hasNextPage){ e'jR<ln|
this.hasNextPage = hasNextPage; 2`z+_DA
} &,\S<B2.
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/** \3KCZ
* @return `@ObM[0p(
* Returns the hasPrePage. {>i'Pb0mG|
*/ l6O2B/2j
publicboolean getHasPrePage(){ 71~V*
return hasPrePage; wxoBq{r;
} L3/ua
U{ Y)\hR-
/** A_2ppEG
* @param hasPrePage i,~{{XS<
* The hasPrePage to set. (<f[$ |%
*/ N>/U%01a
publicvoid setHasPrePage(boolean hasPrePage){ wC[J=:]tA5
this.hasPrePage = hasPrePage; !:>y.^O
} 6 2LZ}yn_"
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/** ]t,ppFC#
* @return Returns the totalPage. NZl0sX.:
* ur'A ;B
*/ GUK/Xiu
publicint getTotalPage(){ qvT9d7x
return totalPage; u^`B#b'
} # OJD<=")
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/** rsP1?Hxq
* @param totalPage zRz3ot,|
* The totalPage to set. ci$o~b6V
*/ FNUue
publicvoid setTotalPage(int totalPage){ |ey6Czm
this.totalPage = totalPage; 7==Uoy*O
} 4g6d6~098;
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} ?(mlt"tPk
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;}r#08I
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 {6n B83BB
5VISP4a
个PageUtil,负责对Page对象进行构造: N~a?0x
java代码: d9E:LZy
YS;Ql\4
nY6^DE2f
/*Created on 2005-4-14*/ gHTo|2 Q{
package org.flyware.util.page; v67o>`<$
FzNs >*
import org.apache.commons.logging.Log; %=GnGgu
import org.apache.commons.logging.LogFactory; \s,ZE6dQ
#/YKA{
/** E$RH+):|
* @author Joa xY@V.
* r;9F@/
*/ h'wI/Z_'
publicclass PageUtil { %POoyH@D}
t,&1~_9
privatestaticfinal Log logger = LogFactory.getLog x;kW }U
"*?^'(yA@
(PageUtil.class); /Wt<[g#
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/** Iz
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* Use the origin page to create a new page c$>Tfa'H
* @param page Z5+qb
* @param totalRecords aj1Zi3h
* @return TJ+yBMd*%
*/ 3C5<MxtK
publicstatic Page createPage(Page page, int edA.Va|0
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totalRecords){ ZXp=QH+f
return createPage(page.getEveryPage(), 40mgB4I
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page.getCurrentPage(), totalRecords); $+-2/=>Xk
} ,zO!`|I
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/** Yf<6[(6 O
* the basic page utils not including exception lLl^2[4k5
8M!If
handler NKh 8'=S
* @param everyPage KYMz
* @param currentPage #pLd';
* @param totalRecords Kk-A?ju@g
* @return page 5ILce%#zL
*/ `Fnt#F}
publicstatic Page createPage(int everyPage, int ~Sh8. ++}
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currentPage, int totalRecords){ '9*(4/,UJJ
everyPage = getEveryPage(everyPage); tKu'Q;J
currentPage = getCurrentPage(currentPage); kbiMqiPG
int beginIndex = getBeginIndex(everyPage, qauk,t
# sm>;+J
currentPage); QF
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int totalPage = getTotalPage(everyPage, r,a V11{
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totalRecords); a|{RK}|3
boolean hasNextPage = hasNextPage(currentPage, ^GHA,cSf
F^z&s]^~
totalPage); Y2HF
boolean hasPrePage = hasPrePage(currentPage); 1r'skmxq
p78X,44xg
returnnew Page(hasPrePage, hasNextPage, >Ta|#]{
everyPage, totalPage, {L4ta~2/T
currentPage, ]gx]7
CM|?;PBuv
beginIndex); c/%i,N\5
} cba~
6O>NDTd%
privatestaticint getEveryPage(int everyPage){ -lAX-W0
return everyPage == 0 ? 10 : everyPage; h`;w/+/Zr
} %i6i.TF
f+d[Q1
privatestaticint getCurrentPage(int currentPage){ }\?UmuolQ
return currentPage == 0 ? 1 : currentPage; EPkmBru
^
} <#k(g\/R
n j0!
privatestaticint getBeginIndex(int everyPage, int Myvp PW
T 5$db-^
currentPage){ ^Q0%_V,
return(currentPage - 1) * everyPage; \("|X>00
} Bs:INvhYW
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privatestaticint getTotalPage(int everyPage, int xJlf}LEyF
DSf
totalRecords){ {)=h
int totalPage = 0; ^M_0M
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if(totalRecords % everyPage == 0) g]%sX6T
totalPage = totalRecords / everyPage; .EpcMXT%
else cdY|z]B
totalPage = totalRecords / everyPage + 1 ; >PHin%#
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return totalPage; 7|bzopLJk
} bh
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privatestaticboolean hasPrePage(int currentPage){ 3V2dN)\
return currentPage == 1 ? false : true; M ^S <G
} :rR)rj'
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privatestaticboolean hasNextPage(int currentPage, j%%& G$Tfu
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int totalPage){ T8'm{[C
return currentPage == totalPage || totalPage == WOkAma-
Pk)>@F<
0 ? false : true; JiH^N!
} p^J=*jm)x
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} apy9B6%PJ+
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 A~0eJaq+
lFJDdf2:$C
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 'ip2| UG
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做法如下: P-]u&m/6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :yFUlO:
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的信息,和一个结果集List: d0U-:S-
java代码: !DU4iq_.
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/*Created on 2005-6-13*/ p#;I4d G
package com.adt.bo; :}0>IPW-V
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import java.util.List; 2J;_9
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import org.flyware.util.page.Page; r{g8CIwGQ
C!X"0]@FA
/** a)lS)*Y
* @author Joa 8@rddk
*/ Ar{7H)V:
publicclass Result { Rq@M~;p
(Y!{ UNq5
private Page page; +YD_ L
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private List content; 4>R)2g
RwyX,|
/** ^L?2y/
* The default constructor Lqa|9|!
*/ <Dk6o`7^N
public Result(){ %r
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super(); 'LX]/D
} b%wm-p
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/** BS*Y3 $
* The constructor using fields XU5GmGu_+
* AJYZ`
* @param page }t%2giJ
* @param content pE4yx5r5
*/ h[(.
public Result(Page page, List content){ .QVN&UyZ
this.page = page; 9 `+RmX;m
this.content = content; i&mt-
} pOq9J7BS
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/** IoKN.#;^
* @return Returns the content. _jWGwO
*/ taBCE?{
publicList getContent(){
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return content; /<
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} O_4j"0
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/** iy-~CPNB_
* @return Returns the page. F a+#bX7
*/ 2 Q}^<^r
public Page getPage(){ K#;EjR4H
return page; AGGNJ4m
} p N+1/m,
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/** ?s]+2Tq
* @param content rO[ Zx'a
* The content to set. / n@by4;W
*/ tRYi q
public void setContent(List content){ bIy:~z5
this.content = content; _z6 " C8W
} *f-8egt-
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/** k#"}oI{<
6
* @param page :{=2ih-}
* The page to set. \5DOp-2
*/
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publicvoid setPage(Page page){ *pSD[E>SU
this.page = page; AQgagE^
} z8JdA%YBM
} j|owU
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}@TtX\7(D
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? t_$C,A+
2. 编写业务逻辑接口,并实现它(UserManager, :9]"4ktoJ
5Y#~+Im=[@
UserManagerImpl) 1kczlTF
java代码: Oi4y~C_Xd
krecUpo
i p;
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/*Created on 2005-7-15*/ -F&*>?I
package com.adt.service; lG R6S
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import net.sf.hibernate.HibernateException; bM>5=Zox
T :0#se
import org.flyware.util.page.Page; F.$NYr/|y
cr>"LAi
import com.adt.bo.Result; R4AKp1Y
Sp\
7
/** {GhM,-%e
* @author Joa d: LP8
*/ :<PwG]LO
publicinterface UserManager { [DSD[[
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public Result listUser(Page page)throws 7q@>d(xho
b
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HibernateException; ZnZ`/zNO
Sr4/8BZ
} ~ L?q.*q
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j6#RV@ p`
LgJUMR8vUO
%y[
t+)!E
java代码: ^nN@@\-5
56!/E5qgW
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/*Created on 2005-7-15*/ w;]~2$
package com.adt.service.impl; ]:n! \G
hWAZP=H
import java.util.List; "!z9UiA
IiB"F<&[j{
import net.sf.hibernate.HibernateException; +^<-;/FZue
+ieRpVg
import org.flyware.util.page.Page; M2rgB%W)m
import org.flyware.util.page.PageUtil; eGk`Z>
Y~g*"J5j
import com.adt.bo.Result; P<MNwdf(+
import com.adt.dao.UserDAO; dZ{yNh.]
import com.adt.exception.ObjectNotFoundException; ,+o*>fD
import com.adt.service.UserManager; TW!>~|U)y
woyeKOr
/** Hmv@7$9s\
* @author Joa ~]C m
*/ qV7nF
}V{
publicclass UserManagerImpl implements UserManager { X~>2iL
I7} o>{
private UserDAO userDAO; %bZ}vJ5b
m)"wd$O^w
/** b^C2<'
* @param userDAO The userDAO to set. CSNfLGA
*/ Uv%?z0F<C
publicvoid setUserDAO(UserDAO userDAO){ 3!2TE -
this.userDAO = userDAO; &pEr;:E
} HiPd|D
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/* (non-Javadoc) HWxwG'EEY,
* @see com.adt.service.UserManager#listUser \Ss6F]K]
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(org.flyware.util.page.Page) 5/C#*%EH'
*/ Fpckb18}(O
public Result listUser(Page page)throws +lED6]+%
k \V6q9*
HibernateException, ObjectNotFoundException { V^E.9fs,
int totalRecords = userDAO.getUserCount(); wC>Xu.Z:
if(totalRecords == 0) g4NbzU[I
throw new ObjectNotFoundException r0fEW9wL
<ecif_a=m
("userNotExist"); m
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page = PageUtil.createPage(page, totalRecords); } 0x'm
List users = userDAO.getUserByPage(page); !R"iV^?V
returnnew Result(page, users); (^;Fyf/
} cUK9EOPe
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} :vRUb>z
mIm.+U`a2
hkoCbR0}8
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:8 jaW?~
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <imIgt|`2
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nlc?
询,接下来编写UserDAO的代码: BZ"+ ND9m_
3. UserDAO 和 UserDAOImpl: 1PnWgu
java代码: mQqv{1
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6%t>T~x
/*Created on 2005-7-15*/ eZk4$y
package com.adt.dao; 3PgiV%]
zD%@3NA41
import java.util.List; 2m0laJ3p9
I'>r
import org.flyware.util.page.Page; $pGdGV\H
o<\9OQ0
import net.sf.hibernate.HibernateException; gy6Pf4Yo
t-3y`31i.
/** 7qT>wCVT
* @author Joa 1:VbbOu->V
*/ TaTs-]4
publicinterface UserDAO extends BaseDAO { kZJ.G
3gNVnmZG
publicList getUserByName(String name)throws h4lrt
ZA
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HibernateException; /R!/)sg
3 F ke#t
publicint getUserCount()throws HibernateException; }J-+^
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