Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 hH )jX`Ta
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~ E>D0o
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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 ;oWh Tj`
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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 ~e,
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分页支持类: bN<c5
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java代码: T*-*U/
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package com.javaeye.common.util; 3,3{wGvHHW
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import java.util.List; roj/GZAy"
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publicclass PaginationSupport { Nz*qz"T
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publicfinalstaticint PAGESIZE = 30; ;7tOFsV
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privateint pageSize = PAGESIZE; ,'={/)c<
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privateList items; 1K09iB
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privateint totalCount; gC<\1AIu
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privateint[] indexes = newint[0]; }1z=
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privateint startIndex = 0; 7{8!IcR #
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public PaginationSupport(List items, int @bfaAh~
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totalCount){ A{y3yH`#h
setPageSize(PAGESIZE); 3vQ?vS|2
setTotalCount(totalCount); hY-;Wfg
setItems(items); |KplbU0iC
setStartIndex(0); TjgX' j
} b;9v.MZ4>g
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public PaginationSupport(List items, int 08yTTt76t
j)'V_@
totalCount, int startIndex){ IC92lPM }
setPageSize(PAGESIZE); _Dwn@{[(8
setTotalCount(totalCount); _+z@Qn?#6h
setItems(items); $J=9$.4"
setStartIndex(startIndex); =
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} 7s<v06Wo
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public PaginationSupport(List items, int 1PjSa4
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totalCount, int pageSize, int startIndex){ AG/nX?u7)t
setPageSize(pageSize); w+2:eFi=/
setTotalCount(totalCount); 7.8ukAud
setItems(items); b0riiF
setStartIndex(startIndex); Xb)XV$0
} $M$oNOT}Y
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publicList getItems(){ 9 n|H%AC
return items; xqmJPbA
} %}+j4n
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publicvoid setItems(List items){ $ hg
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this.items = items; "aB]?4
} yr[iAi"
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publicint getPageSize(){ a!Z,~ V8
return pageSize; |1-0x%@[ ;
} kS/Zb3
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publicvoid setPageSize(int pageSize){ 8
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this.pageSize = pageSize; Vnv<]D
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} p9oru0q
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publicint getTotalCount(){ 2ZNTg@o
return totalCount; 2X]2;W)S;
} g#9KG
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publicvoid setTotalCount(int totalCount){ n KDX=73
if(totalCount > 0){ +3]@0VM26;
this.totalCount = totalCount; m-*du(
int count = totalCount / Ocx=)WKdW
9);a 0}*5
pageSize; UKMrR9[x*
if(totalCount % pageSize > 0) !_l W#feR
count++; ]c[80F-
indexes = newint[count]; 'ZTE"KT
for(int i = 0; i < count; i++){ .~ZNlI {K
indexes = pageSize * Fg5>CppH
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i; kpxd+w
} )h2wwq0]
}else{ _9\ayR>d
this.totalCount = 0; QOy+T6en
} DH)@8)C
} niqi DT/
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publicint[] getIndexes(){ _2 }i8q:
return indexes; &wK%p/?
} -]W AB9
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publicvoid setIndexes(int[] indexes){ L$i&>cF\_>
this.indexes = indexes; m)=
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} Le|Ho^h,Y
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publicint getStartIndex(){ WP2|0ib
return startIndex; (!W:-|[K\
} $MB56]W8
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publicvoid setStartIndex(int startIndex){ ?J%$;"q
if(totalCount <= 0) i/-Xpj]Zf
this.startIndex = 0; *D*K`dk
elseif(startIndex >= totalCount) VISNmz2P
this.startIndex = indexes %89f<F\V
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[indexes.length - 1]; _Bb/~^
elseif(startIndex < 0) Y.[^3
this.startIndex = 0; $-jj%x\}
else{ <M7@JgC &
this.startIndex = indexes EAj2uV
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[startIndex / pageSize]; GT|=Apnwr%
} bkLm]n3
} [fxAj]
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publicint getNextIndex(){ 7W5FHZd'
int nextIndex = getStartIndex() + T&w3IKb|}
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pageSize; .!l#z|/x
if(nextIndex >= totalCount) \_De(
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return getStartIndex(); #wk'&XsC#z
else Z+(V'e;
return nextIndex; "_}Hzpy5k
} J0C,KU(
8`U5/!6fu
publicint getPreviousIndex(){ $*9h\W-)`Q
int previousIndex = getStartIndex() - Do=*bZ;A
k
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pageSize; H.'MQ
if(previousIndex < 0) .FXq4who
return0; K /g\x0
else ,*@m<{DX)
return previousIndex; kJZBQ<^
} HZkC3$
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} _F;(#D
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抽象业务类 UStZ3A'
java代码: PfF7*}P
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/** _;G"{e.=
* Created on 2005-7-12 iNT 1lk
*/ O-U_Zx0zd
package com.javaeye.common.business; [3]!*Cd
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import java.io.Serializable; w`CGDF\Oo
import java.util.List; e7{3:y|]d3
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import org.hibernate.Criteria; 4u"V52
import org.hibernate.HibernateException; rgRh ySud
import org.hibernate.Session; A+iQH1C0h
import org.hibernate.criterion.DetachedCriteria; eeoIf4]
import org.hibernate.criterion.Projections; wHx1CXC
import u/hFf3
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org.springframework.orm.hibernate3.HibernateCallback; lJ62[2=V
import '2WYbcU
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org.springframework.orm.hibernate3.support.HibernateDaoS o/CSIvz1
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upport; oi::/W|A+
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import com.javaeye.common.util.PaginationSupport; ]O,!B''8k
y4/>3tz;
public abstract class AbstractManager extends 5Q?7 xTQ
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HibernateDaoSupport { ]mn(lK
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privateboolean cacheQueries = false; kgEGL]G>
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privateString queryCacheRegion; s~6?p%
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publicvoid setCacheQueries(boolean DCACj-f
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cacheQueries){ c}U&!R2p{
this.cacheQueries = cacheQueries; Y 'Yoc
} Ki,]*-XO
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publicvoid setQueryCacheRegion(String c#<v:b
([qw#!;w;
queryCacheRegion){ &s_[~g<
this.queryCacheRegion = WID4 {>G2
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queryCacheRegion; JrQd7
} u%Hegqn
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publicvoid save(finalObject entity){ Zh)Qq?H
getHibernateTemplate().save(entity); $Dxz21|P7
} pfe9n[
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publicvoid persist(finalObject entity){ NJ/6_e
getHibernateTemplate().save(entity); nBgksB*A
} xx)egy_
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publicvoid update(finalObject entity){ /(bPc12
getHibernateTemplate().update(entity); pUZbZ
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} GO.mT/rB
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publicvoid delete(finalObject entity){ Q0Y0Zt,h
getHibernateTemplate().delete(entity); wcspqC" _
} c*'D
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publicObject load(finalClass entity, HpiP"Sl
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finalSerializable id){ y[UTuFv~Q
return getHibernateTemplate().load <T>C}DGw
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(entity, id); I8d#AVF2
} <{Wsh#7 }.
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publicObject get(finalClass entity, c`yLn%Of%
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finalSerializable id){ [[}KCND
return getHibernateTemplate().get QmvhmsDL
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(entity, id); vrXUS9i.
} %G1kkcdH<
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publicList findAll(finalClass entity){ )[|`-M~u
return getHibernateTemplate().find("from Smzy EMT
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" + entity.getName()); %a{$M{s
} y/Fv4<X
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publicList findByNamedQuery(finalString OGw =e{
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namedQuery){ 4eMNKIsvY$
return getHibernateTemplate 9+)5 #!0
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().findByNamedQuery(namedQuery); 8
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} /~yk
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publicList findByNamedQuery(finalString query, R*3x{DNL
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finalObject parameter){ v)mO"\
return getHibernateTemplate ZW{pO:-
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().findByNamedQuery(query, parameter); _5 Zhv-7
} Z&e_yl
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publicList findByNamedQuery(finalString query, g]PmmK_L
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finalObject[] parameters){ ln-+=jk
return getHibernateTemplate {x{e?c!
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().findByNamedQuery(query, parameters); {s&6C-
} h W\q
@iWql*K;m
publicList find(finalString query){ 8Ux3,X=
return getHibernateTemplate().find 4,"%
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(query); ^"WrE(3
} d%FD=wm
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publicList find(finalString query, finalObject &sleV5V
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parameter){ th]1>
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return getHibernateTemplate().find 7t
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(query, parameter); 0\*[7!`s
} sDA&U9;
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public PaginationSupport findPageByCriteria @2ZE8O#I
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(final DetachedCriteria detachedCriteria){ FGY4 u4y
return findPageByCriteria = s^KZV
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]f#1G$
} Loo48
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public PaginationSupport findPageByCriteria j#mo Vq
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(final DetachedCriteria detachedCriteria, finalint :!H]gC
4
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startIndex){ |zhVl
return findPageByCriteria ;LSdY}*%0
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(detachedCriteria, PaginationSupport.PAGESIZE, >Z@^R7_W
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startIndex); I,J*\)-%J
} d;1%Ei3K
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public PaginationSupport findPageByCriteria yzJ
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(final DetachedCriteria detachedCriteria, finalint M_asf7|v
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pageSize, 1Z-f@PoM
finalint startIndex){ J<J_yRg2
return(PaginationSupport) !;EG<ji,gj
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getHibernateTemplate().execute(new HibernateCallback(){ Qxb5Y)/jn
publicObject doInHibernate X;`XkOjk
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(Session session)throws HibernateException { >HMuh)
Criteria criteria = ,FWC|uM"
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detachedCriteria.getExecutableCriteria(session); R)4L]ZF
int totalCount = B^Z %38o
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((Integer) criteria.setProjection(Projections.rowCount 5>{
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()).uniqueResult()).intValue(); o9&&u1`M/
criteria.setProjection hes$LH
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(null); lU6?p")F1
List items = 2 VgFP3
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criteria.setFirstResult(startIndex).setMaxResults m^hi}Am1
hbfTv;=z
(pageSize).list(); +JQ/DNv
PaginationSupport ps = 24;F~y8H
]!l]^/.
new PaginationSupport(items, totalCount, pageSize, 9&(d2
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startIndex); -U'3kaX5<
return ps; :f1Q0klwP
} (vL-Z[M!
}, true); H#yBWvj*H
} v(PwE B]
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public List findAllByCriteria(final Buazm3q8H
#Fp5>%*
DetachedCriteria detachedCriteria){ ibe#Y
return(List) getHibernateTemplate @&H Tt
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().execute(new HibernateCallback(){ eAvOT$
publicObject doInHibernate 6KT]3*B
}@VdtH
(Session session)throws HibernateException { ue?e}hF
Criteria criteria = ]r6S|;:
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detachedCriteria.getExecutableCriteria(session); )L^GGy8w
return criteria.list(); e}V3dC^pU
} dw6U}
}, true); aE]/w1a
} kTJz .
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public int getCountByCriteria(final l]:nncpns
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DetachedCriteria detachedCriteria){ 0xv@l^B
Integer count = (Integer) !aylrJJ
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getHibernateTemplate().execute(new HibernateCallback(){ %qN_<W&Ze
publicObject doInHibernate % Q| >t~
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(Session session)throws HibernateException { oaxCcB=\
Criteria criteria = k{M4.a[(
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detachedCriteria.getExecutableCriteria(session); x+1Cs$E;
return "DWw]\xO](
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criteria.setProjection(Projections.rowCount W+F{!dW
,_ zivUU
()).uniqueResult(); 8v eG^o
} 7t8[M(
}, true); k(<:
return count.intValue();
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} 7bC1!x*qw
} ?<_yW#x6
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用户在web层构造查询条件detachedCriteria,和可选的 .TI=3*`G
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 &nJH23h^
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PaginationSupport的实例ps。 <oJM||ZA
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ps.getItems()得到已分页好的结果集 e|6kgj3/
ps.getIndexes()得到分页索引的数组 :[hZn/
ps.getTotalCount()得到总结果数 e7T}*Up
ps.getStartIndex()当前分页索引 +`y{r^xD
ps.getNextIndex()下一页索引 ihv=y\Jt
ps.getPreviousIndex()上一页索引 l y!vbpE_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 x%J4A+kU
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 j<BW/
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一下代码重构了。 PTt#Ixn,
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我把原本我的做法也提供出来供大家讨论吧: .mr&zq
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首先,为了实现分页查询,我封装了一个Page类: D9hV`fA
java代码: U,;a+z4\
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/*Created on 2005-4-14*/ !06
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package org.flyware.util.page; %A]?5J)Bi
E.ugr])
/** bSG}I|
* @author Joa //x^[fkNq)
* f1Az|h
*/ m'j]T/WF
publicclass Page { T+a\dgd
<%_7%
/** imply if the page has previous page */ D@O#P^?
privateboolean hasPrePage; (pDu
<./r%3$;7
/** imply if the page has next page */ As5*)o"&
privateboolean hasNextPage; "UNWbsn6Qr
9A7LDHst7
/** the number of every page */ *h <_gn
privateint everyPage; -VC
kk
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/** the total page number */ e1Ne{zg~
privateint totalPage; rAv)k&l
PUU
"k:{
/** the number of current page */ QsO%m
privateint currentPage; 9 a$\l2
C>}@"eK
/** the begin index of the records by the current Q+i
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query */ uPbGQ :%}
privateint beginIndex; t9QnEP'
fV "gL(7
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/** The default constructor */ uG\ @e'pr
public Page(){ Ro2Ab^rQ|
006qj.
} 6bE~m<B\`
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/** construct the page by everyPage 8LPvb#9=
* @param everyPage c[E"
* */ k <EzYh
public Page(int everyPage){ b +4x2{
this.everyPage = everyPage; t7P[^f15[
} @ P'("qb~
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/** The whole constructor */ l KdY!j"
public Page(boolean hasPrePage, boolean hasNextPage, VfV|fuW
cFV)zFu
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int everyPage, int totalPage, u&E$(
int currentPage, int beginIndex){ :j<ij]rsI
this.hasPrePage = hasPrePage; Ic<J]+Xq
this.hasNextPage = hasNextPage; D#.N)@\
this.everyPage = everyPage; F%-KY$%
this.totalPage = totalPage; iXgy/>qgT
this.currentPage = currentPage; e`7dRnx&0
this.beginIndex = beginIndex; *WQl#JAr
} ~MpcVI_K
MEI.wJZ
/** Xc}~_.]
* @return =O.%)|
* Returns the beginIndex. m4m,-}KNi
*/ J
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publicint getBeginIndex(){ iVUkM3
return beginIndex; I'%\
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} x%`.L6rj
\F; S
/** 5bZjW~d
* @param beginIndex e,X{.NS
* The beginIndex to set. 4b@Awtk
*/ O: J;zv\
publicvoid setBeginIndex(int beginIndex){ Cqra\
this.beginIndex = beginIndex; @p\te7(P%
} -#y^$$i0
{L#+v~d^'n
/** 4iPxtVT
* @return X }""=
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* Returns the currentPage. w vnuE<o8
*/ NDo>"in
publicint getCurrentPage(){ 37U2Tb!y'
return currentPage; LP{@r ic
} .wPu
#*
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/** /ygC_,mx
* @param currentPage S [=l/3c
* The currentPage to set. y88lkV4a
*/ 9x]yu6
publicvoid setCurrentPage(int currentPage){ a*N<gId
this.currentPage = currentPage; {0IC2jE
} R)Y*<Na
:9.QhY)D
/** uJ:SN;
* @return },& =r= B
* Returns the everyPage. |%tI!RN):
*/ SmMJ%lgA6
publicint getEveryPage(){ 713)D4y}
return everyPage; x 3C^ S~
} 8jdEx&K
+wpQ$)\
/** 8j^3_lD
* @param everyPage :dML+R#Ymh
* The everyPage to set. LEgx"H=c
*/ na0-v-
publicvoid setEveryPage(int everyPage){ pN-c9n4#j
this.everyPage = everyPage; Gc0/*8u/
} j-n-2:Q
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/**
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* @return )2Dm{T
* Returns the hasNextPage. })TXX7[h
*/ s6HfN'
publicboolean getHasNextPage(){ WW.amv/[a
return hasNextPage; E!6 Nf[
} M!Wjfq
^~
a(|,KWHn
/** 92pl#Igt
* @param hasNextPage qCUn.
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* The hasNextPage to set. F8En)#
*/ rd0[(-
publicvoid setHasNextPage(boolean hasNextPage){ t)n}S;iD
this.hasNextPage = hasNextPage; [Fo"MeH?R
} sR*.i?lN
w"/RI#7.
/**
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* @return ,f3Ck*M
* Returns the hasPrePage. =(\xe|
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*/ ](tv`1A,Wd
publicboolean getHasPrePage(){ O~L/>Ya
return hasPrePage; iI@m e=
} {T(z@0Xu
"<^]d~a_
/** JQdeI+
* @param hasPrePage okSCM#&:[2
* The hasPrePage to set. a?gziCmS?C
*/ 5.o{A#/NTl
publicvoid setHasPrePage(boolean hasPrePage){ 8r-'m%l
this.hasPrePage = hasPrePage; <}z,!w8
} ,EuJ0]2
SBog7An9SI
/** 4.o[:5'
* @return Returns the totalPage. #CcWsI>+w>
* :,*{,^2q:
*/ u^Ss8}d
publicint getTotalPage(){ |j>fsk~
return totalPage; Xx;4
} 0!(BbQnWI
uNS ]n}
/** c_+y~X)i
* @param totalPage cpe/GvD5]
* The totalPage to set. - )brq3L
*/ -<RG'I~
publicvoid setTotalPage(int totalPage){ Smjg[
this.totalPage = totalPage; 48t_?2>
} =j$!N# L
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,
} ye^l~
^N2N>^'&1.
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8Ug`2xS<_
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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 _=d
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个PageUtil,负责对Page对象进行构造: Zyx92z9Y
java代码: _WeN\F~^
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/*Created on 2005-4-14*/ cN]]J
package org.flyware.util.page; \8HLQly|@
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import org.apache.commons.logging.Log; JAA{5@ST
import org.apache.commons.logging.LogFactory; {24Y1ohK
9YjO
/** WymBjDos:
* @author Joa &:MfLDJ
* V {H/>>k7
*/ ZUiInO
publicclass PageUtil { A;g{H|
hD I}V1)
privatestaticfinal Log logger = LogFactory.getLog Bx&F* a;5
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(PageUtil.class); eo~>|0A*V
,*}5xpX
/** erQ0fW
* Use the origin page to create a new page >QJfTkD$
* @param page sH}q &=
* @param totalRecords ;?`l1:C5)
* @return cHO8%xu`
*/ JMa[Ulz
publicstatic Page createPage(Page page, int X8Ld\vZYn
'dFhZ08u}
totalRecords){ y!;PBsU%Sx
return createPage(page.getEveryPage(), FJj #
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page.getCurrentPage(), totalRecords); !o k6*m
} *gxo!F}
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/** -Ze{d$
* the basic page utils not including exception EDkxRfY2/
z%pD3J?>
handler 9^5D28y
* @param everyPage aTx*6;-PH
* @param currentPage 3>I
* @param totalRecords 8iDg2_l`G
* @return page -<0PBl
*/ Q:#Kt@W
publicstatic Page createPage(int everyPage, int V&>\U?q:
<P"4Mk7`s
currentPage, int totalRecords){ ;& PK6G
everyPage = getEveryPage(everyPage); $^1L|KgXp
currentPage = getCurrentPage(currentPage); V;V,G+0Re
int beginIndex = getBeginIndex(everyPage, OSsxO(;g
aYyUe>
currentPage); },=0]tvZG#
int totalPage = getTotalPage(everyPage, `Rc7*2I)l
d*A(L5;@
totalRecords); uv,_?x\'
boolean hasNextPage = hasNextPage(currentPage, mm5y'=#
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totalPage); U=G^wL
boolean hasPrePage = hasPrePage(currentPage); +-B`Fya
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returnnew Page(hasPrePage, hasNextPage, S_B $-H|
everyPage, totalPage, /W,K% s]
currentPage, C;3>q*Am4
=CE(M},d
beginIndex); fzVU9BU
} ZPISclSA+
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privatestaticint getEveryPage(int everyPage){ p`i_s(u
return everyPage == 0 ? 10 : everyPage; F$QAWs
} g+-=/Ge
,VM)ZK=Tr
privatestaticint getCurrentPage(int currentPage){ c&o|I4|Y,
return currentPage == 0 ? 1 : currentPage; gtBnP~zT\B
} D =Pv:)*]
a V4p0s6ZZ
privatestaticint getBeginIndex(int everyPage, int u*<G20~A
K^_Mt!%
currentPage){ H$/r{gfg^
return(currentPage - 1) * everyPage; h]#wwJF
} 7fOk]Yl[
[uh$\s7
privatestaticint getTotalPage(int everyPage, int ThLnp@
<Y(lRM{
totalRecords){ V|h/a\P
int totalPage = 0; t1I` n(]n
+6xEz67A<
if(totalRecords % everyPage == 0) 73C
totalPage = totalRecords / everyPage; AV0C9a/td
else 1f"LAs`%
totalPage = totalRecords / everyPage + 1 ; ZXf^HK
$1CAfSgKw
return totalPage; G(puC4 "&
} Ikkv <uY
Y68T&swD
privatestaticboolean hasPrePage(int currentPage){ =DhzV
D
return currentPage == 1 ? false : true; '5ZtB<
} E,#J\)'z
`+!GoXI
privatestaticboolean hasNextPage(int currentPage, M=}vDw]Q
zlh}8Es
int totalPage){ @CSTp6{y
return currentPage == totalPage || totalPage == #NAlje( 7
95,{40;X7
0 ? false : true; *Q<%(JJ
} |$r|DX1[
;btH[a iV
zk[%YG&
} v;9VX
V8z91
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n%Vt r
qq&G~y
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。 rf% E+bh4
,Z7tpFC
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 '~^3 =[Z
*j,5TO-j
做法如下: $Q[>v!!X
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 aqjS 5!qh
~$0Qvyb>
的信息,和一个结果集List: 0YsC@r47wL
java代码: {-sy,EYcw
>qJRpO
!cs+tm3
/*Created on 2005-6-13*/ m,e@bJ-
package com.adt.bo; !!=%ty
):.
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import java.util.List; S.9ki<
qp-/S^%
import org.flyware.util.page.Page; #-9;Hn4x
,3k"J4|d
/** 8
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* @author Joa e,_b
*/ glk_*x
publicclass Result { YQ`GOP#/
%bnDxCj"
private Page page; '"H'#%RU
QD0upYG
private List content; qY24Y
p;!'5 f
/** ! K~PH
* The default constructor =OIxG}*
*/ 7XE/bhe%S
public Result(){ "}i\"x;s
super(); 8J:6uO
c|
} ':71;^zXf
"WTnC0<
/** */Oq$3QGsV
* The constructor using fields vjI>TIy
* Vwp fkD`
* @param page UW+|1Bj_:
* @param content R qS2Qo]
*/ %@Nuzdp
public Result(Page page, List content){ taXS>*|B
this.page = page; cvpcadN[
this.content = content; E3#}:6m
} Y`QJcC(3
A L#"j62
/** <_@ S@t)
* @return Returns the content. FAVw80?5k
*/ fbKL31PI
publicList getContent(){ FO{K=9O
return content; Be{7Rj v
} ,z1X{
@|xcrEnP}B
/** qlJP2Ig~
* @return Returns the page. 3F ;+D
*/ (5%OAjW
public Page getPage(){ r%hnl9
return page; }d2]QD#O
} 4/$ $?w4
v\#69J5.>)
/** 3tMFJ ;*`
* @param content @x">e][B
* The content to set. KaC+x-%K
*/ Y@._dliM
public void setContent(List content){ }O<u
this.content = content; V.kUFTCvf
} ![Z'jCpy
=<I 90j~)
/** sm-RpZ&|
* @param page "Y9
*rL
* The page to set. Exox&T
*/ 2H8,&lY.p
publicvoid setPage(Page page){ xX`P-h>V`c
this.page = page; (eI'%1kS<
}
N3Ub|$}q
} mh>)N"
vV:eU-a
jE.U~D)2YF
9u/ "bj
T_:"~
]
2. 编写业务逻辑接口,并实现它(UserManager, w{3
B
[k(oQykq
UserManagerImpl) <U=:N~L
java代码: N=&~3k
Dh0`t@
h>w4{ u0
/*Created on 2005-7-15*/ }tT"vCu
package com.adt.service; aDuO!?Cm
UUy|/z%
import net.sf.hibernate.HibernateException; 0[g8
R_ojK&%
import org.flyware.util.page.Page; b>AFhj :
&Ib8xwb:
import com.adt.bo.Result; 0"$Ui#r`
bNR}Mk]?
/** ~WK>+T,%
* @author Joa "q4c[dna
*/ ,KF>PoySA
publicinterface UserManager { ? &ew$%
5_b`QO
public Result listUser(Page page)throws zJS,f5L6)
ygr[5Tl
HibernateException; 8 ~.|^no
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}0K3,5
} Ob2H7!
Af5O;v\
zlIXia5
dL'hC#!h
/w{DyHT
java代码: #r;
'AG
SLO;c{EFH
iIu
/*Created on 2005-7-15*/ g?!vRid@S
package com.adt.service.impl; K:fK!/
TjGe8L:
import java.util.List; iy Zs:4jkc
$;Lb|~
import net.sf.hibernate.HibernateException; Lz2 AWqR
&*RJh'o|N(
import org.flyware.util.page.Page; =YkJS%)M)
import org.flyware.util.page.PageUtil; @ 'rk[S}A
2`/JT
import com.adt.bo.Result; wy"^a45h
import com.adt.dao.UserDAO; ET1/oG<@
import com.adt.exception.ObjectNotFoundException; I&qT3/SVI
import com.adt.service.UserManager; Ce}wgKzr
oqHI`Tu
/** .|$6Pi%!
* @author Joa >l{<p(
*/ h|"98PI
publicclass UserManagerImpl implements UserManager { cAIMt]_
#>dfP"}&,
private UserDAO userDAO; gbM#jhQ
}Og zSnR
/** 'n%Ac&kk
* @param userDAO The userDAO to set. 7(lR$,bE;=
*/ *;. l/
publicvoid setUserDAO(UserDAO userDAO){ LF?83P,UJ#
this.userDAO = userDAO; Gd1%6}<~
} s2L|J[Y"s
'h_PJ%
/* (non-Javadoc) g2.%x \d
* @see com.adt.service.UserManager#listUser 7!.%HhU0
t<sg8U.
(org.flyware.util.page.Page) $A,fO~
*/ h7<Zkf
public Result listUser(Page page)throws lG,/tMy
IZYq
HibernateException, ObjectNotFoundException { \](IBI:
int totalRecords = userDAO.getUserCount(); O{rgx~lLJt
if(totalRecords == 0) [R-4e; SRh
throw new ObjectNotFoundException kVE%
"
*IUw$|Z6z)
("userNotExist"); B)J.(k`p
page = PageUtil.createPage(page, totalRecords); |ZW%+AQ|
List users = userDAO.getUserByPage(page); cZT;VmC
returnnew Result(page, users); 1ux~dP
} /\*,|y\<
z|[#6X6tT
} x&7%U
LS@[O])$'
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IO~d.Ra
VQV7W
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 EL$"MT}p
saQA:W;
询,接下来编写UserDAO的代码: |2(z<b&y=
3. UserDAO 和 UserDAOImpl: q3Re
F_
java代码: p*)RP2
!/, 6+2Ru
+c#:;&Gs
/*Created on 2005-7-15*/ ik02Q,J
package com.adt.dao; =(b;Cow
betN-n-
import java.util.List; @=q,,t$r
e|u|b
import org.flyware.util.page.Page; 5f2ah4 g
t_ 5b
import net.sf.hibernate.HibernateException; cy8+@77
.f
4a+w
/** }q9;..oL
* @author Joa 5"xZ'M~=
*/ j>X;a39|
publicinterface UserDAO extends BaseDAO { 4a]m=]Hm
CPc<!CC
publicList getUserByName(String name)throws }c(".v#
zlzr;7m
HibernateException; +hL+3`TD#H
"f\2/4EIl
publicint getUserCount()throws HibernateException; ei'=%r8~
(lF;c<69
publicList getUserByPage(Page page)throws 0 (jb19
x;"!
HibernateException; ;mH1J'.(a
]^MOFzSz~
} [q]"_4L0;d
A,D67G<v`
iaO;i1K5U
Z#YkAQHv5
! )$
PD@
java代码: V0+D{|thh6
aCzdYv\} &
1><\3+8
/*Created on 2005-7-15*/ j(/Bf m
package com.adt.dao.impl; G%~=hEK0
vf(8*}'!Q
import java.util.List; Dgh|,LqUB
S@]7
import org.flyware.util.page.Page; ~8~B VwZ_
JmdXh/X
import net.sf.hibernate.HibernateException; rhY>aj
import net.sf.hibernate.Query; .b>1u3
K_j$iHqLF
import com.adt.dao.UserDAO; <(W0N|1v
yyZH1A
/** ,!_
* @author Joa |VMc,_D
*/ s#om
public class UserDAOImpl extends BaseDAOHibernateImpl Kd^{~Wlz&z
?z0f5<dL
implements UserDAO { `C"Slz::
32jOs|<\
/* (non-Javadoc) Rro|P_
* @see com.adt.dao.UserDAO#getUserByName Srj%6rgsB
k^AI7H
(java.lang.String) iK{q_f\"
*/ 2f\;#-
publicList getUserByName(String name)throws }T%;G /W
w#[Ul9=?6
HibernateException { 1BQTvUAA
String querySentence = "FROM user in class |gEA.}
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rm2"pfs
com.adt.po.User WHERE user.name=:name"; %98F>wl
Query query = getSession().createQuery '8>h4s4
6dTq&GZ\
(querySentence); ~d6_
query.setParameter("name", name); JoQzf~
return query.list(); ;:1d<Q|
} avxI\twAU
"Q9S<O8)
/* (non-Javadoc) K;;Q*NN-
* @see com.adt.dao.UserDAO#getUserCount() "6rZn_H/|
*/ kb1{;c:
publicint getUserCount()throws HibernateException { [^t"Hf
int count = 0; ^57[&{MuBF
String querySentence = "SELECT count(*) FROM Lu\]]m
8=ubMqr[
user in class com.adt.po.User"; ~a m]G0
Query query = getSession().createQuery )l*H$8
}/BwFB+(/
(querySentence); ?TLEZlB2"
count = ((Integer)query.iterate().next K0 .f4o
LB%_FT5
()).intValue(); KY/}jJW
return count; w~M5)b
} J'^s5hxn+0
5}
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/* (non-Javadoc) , M$*c
* @see com.adt.dao.UserDAO#getUserByPage SPW @TF1
>|SB]'C|
(org.flyware.util.page.Page) 2#&9qGR
*/ hABC
rd Em
publicList getUserByPage(Page page)throws P$_Y:XI !
>U~.I2sz
HibernateException { "{;]T
String querySentence = "FROM user in class AWCzu5ve
^T"9ZBkb
com.adt.po.User"; Ne*I$T 5
Query query = getSession().createQuery xjOy3_Js
bT-(lIU
(querySentence); J]ivIQ
query.setFirstResult(page.getBeginIndex()) :xZ/c\
.setMaxResults(page.getEveryPage()); ,S;?3? a
return query.list(); 'dM &~LSQ
} -yfyd$5j
D.)$\Caq
} k6rX/ocu
*JGm
iQ*JU2;7t
#{7=
vIG8m@-!&;
至此,一个完整的分页程序完成。前台的只需要调用 Pgf$GXE
l)D18
userManager.listUser(page)即可得到一个Page对象和结果集对象 Y{Kpopst
o1"U'y-9V
的综合体,而传入的参数page对象则可以由前台传入,如果用 ;&e5.K+.Z
VuFMjY
webwork,甚至可以直接在配置文件中指定。 LfyycC2E
,HS\(Z
下面给出一个webwork调用示例: 1YR;dn
java代码: 5b9_6L6
,0[8/)$M
xr!FDfM.K
/*Created on 2005-6-17*/ is{I5IR\/
package com.adt.action.user; Gh0H)
q
+xRja(d6
import java.util.List; 3O%[k<S\VO
liFNJd`|o+
import org.apache.commons.logging.Log; tr7FV1p
import org.apache.commons.logging.LogFactory; =sedkrM
import org.flyware.util.page.Page; 4nkH0dJQ
_Pa(5-S'KR
import com.adt.bo.Result; D9e"E1f+"
import com.adt.service.UserService; e%x$Cb:znn
import com.opensymphony.xwork.Action; 0sVCTJ@
MdU_zY(c
/** tc@v9`^_
* @author Joa $;7?w-.
*/ aGNt?)8WPZ
publicclass ListUser implementsAction{ *j><a
S +|aCRS
privatestaticfinal Log logger = LogFactory.getLog k]Y+C@g
>!A&@1[M
(ListUser.class); !l~tBJr*sB
&