Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 *]* D^'
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 2f.4P]s`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 [7gwJiK
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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 gq an]b_
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。 wM&WR2
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分页支持类: 2^=.jML[
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java代码: ]LZ,>v
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package com.javaeye.common.util; ]$?\,`
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import java.util.List; %R LGO&
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publicclass PaginationSupport { o:Q.XWa@MG
jd?NN:7
publicfinalstaticint PAGESIZE = 30; {-)*.l=
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privateint pageSize = PAGESIZE; =CjN=FM
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privateList items; q.NvwJ
,N`D{H"F
privateint totalCount; M[,G#GO
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privateint[] indexes = newint[0]; DU1\ K
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privateint startIndex = 0; bdkxCt
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public PaginationSupport(List items, int Blnc y
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totalCount){ mY,t]#^m7
setPageSize(PAGESIZE); #~`]eM5`J
setTotalCount(totalCount); keL!;q|r-)
setItems(items); ?tFsSU
setStartIndex(0); .q9wyVi7GI
} ~Y'j8W
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public PaginationSupport(List items, int L% ?3VW
##clReS
totalCount, int startIndex){ XbKNH>
setPageSize(PAGESIZE); Ba /^CS
setTotalCount(totalCount); JLH,:2
setItems(items); YN 31Lo
setStartIndex(startIndex); A J"/T+g_
} RTRi{p
q X>\*@
public PaginationSupport(List items, int {Qr0pjE7R
Y+'522er
totalCount, int pageSize, int startIndex){ gtV*`g
setPageSize(pageSize); 3&z.m/
setTotalCount(totalCount); rE&+fSBD
setItems(items); f6zS_y9gn
setStartIndex(startIndex); <tp#KZE
} "/}cV5=Z
e3b|z.^ 8
publicList getItems(){ 6`l7saHXE
return items; WYNO6Xb#:
} f:|O);nM
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publicvoid setItems(List items){ {r2fIj~V
this.items = items;
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} a#G]5TZ
cPm-)/E)i
publicint getPageSize(){ S|?Ht61k
return pageSize; &b7i> ()
} %1jApCJ
*.ZU" 5e
publicvoid setPageSize(int pageSize){ JDy ;Jb
this.pageSize = pageSize; I~.d/!>Z
} <OC|z3na_
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publicint getTotalCount(){ yL>wCD,L
return totalCount; l`A4)8Y@
} I_h{n{,sr
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publicvoid setTotalCount(int totalCount){ +|=5zWI/
if(totalCount > 0){ 7yK1Q_XY>
this.totalCount = totalCount; 8${Yu
int count = totalCount / eX@7f!uz
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pageSize; GxR, 3
if(totalCount % pageSize > 0) {BlKVsQ
count++; U\\nSU
indexes = newint[count]; ,@'M'S
for(int i = 0; i < count; i++){ xFY<
ns
indexes = pageSize * Udh!%QP%[w
bhb*,iWA
i; !(wH}ti
} k;9"L90
}else{ 2og8VI
this.totalCount = 0; =!cI@TI
} @\UoZv(
} >)IXc<"wq
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publicint[] getIndexes(){ %g<J"/
return indexes; }_{QsPx9
}
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publicvoid setIndexes(int[] indexes){ > \KVg(?D
this.indexes = indexes; FTg4i\Wp
} hIr$^%
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publicint getStartIndex(){ k v}<u
return startIndex; KtFxG6a
} S"z cSkF
a} w%k
publicvoid setStartIndex(int startIndex){ khW9n*
if(totalCount <= 0) X0.-q%5
this.startIndex = 0; u70-HFI@
elseif(startIndex >= totalCount) [8K+zT5
this.startIndex = indexes F}lgy;=h
l< y9ue=
[indexes.length - 1]; *I(g~p
elseif(startIndex < 0) Ph&fOj=pFb
this.startIndex = 0; Sp]i~#q_'
else{ P;dp>jL
this.startIndex = indexes .u_k?.8|
_ x.D< n=X
[startIndex / pageSize]; g}-Ch#
} XT|!XC!|
} weOzs]uc
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publicint getNextIndex(){ WSY&\8
int nextIndex = getStartIndex() + -|DSfI#j
@MV%&y*z.
pageSize; r12{XW?~
if(nextIndex >= totalCount) Pj!{j)-tS
return getStartIndex(); /~LXY<-(
else ecH-JPm'
return nextIndex; ClH aR
} QxGQF|
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publicint getPreviousIndex(){ 47iwb
int previousIndex = getStartIndex() - B9Dh^9?L
Qw$"W/&X
pageSize; LxGE<xj|V%
if(previousIndex < 0) x,Cc$C~YP
return0; `FImi9%F
else ItTIU
return previousIndex; JL9d&7-
} lbES9o5
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}
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抽象业务类 X*~NE\
java代码: @Y>3 -,o,S
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/** RZfC?
* Created on 2005-7-12 _^RN
C)ol
*/ >5Zpx8W
package com.javaeye.common.business; 8-5a*vV,>
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import java.io.Serializable; j8os6I
import java.util.List; Ar sMqb
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^vBp
import org.hibernate.Criteria; cLlfncI
import org.hibernate.HibernateException; KrkZv$u,
import org.hibernate.Session; )).;p_nLZ
import org.hibernate.criterion.DetachedCriteria; 1V`]sfRK
import org.hibernate.criterion.Projections; -aNTFt~|[
import 9ok|]d P
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org.springframework.orm.hibernate3.HibernateCallback; (Df<QC`0v
import bq4H4?j
'w%N(N tq
org.springframework.orm.hibernate3.support.HibernateDaoS JMOP/]%D
7/vr!tbL`p
upport; ?E2k]y6<
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import com.javaeye.common.util.PaginationSupport; w c%
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public abstract class AbstractManager extends x#0C+cU
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HibernateDaoSupport { >V(2Ke Y
ke>\.|HT}
privateboolean cacheQueries = false; 1TQ$(bI
Kc udWW]
privateString queryCacheRegion; 8{+~3@T
@sKAsn
publicvoid setCacheQueries(boolean pOI+
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cacheQueries){ 73~Mq7~8
this.cacheQueries = cacheQueries; }WGi9\9T&
} F.8{
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publicvoid setQueryCacheRegion(String N0RFPEQ~
, m|9L{
queryCacheRegion){ ,.FTw,<
this.queryCacheRegion = &up/`8
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queryCacheRegion; X}zKV
} <(p1
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publicvoid save(finalObject entity){ 0HD1Ob^@
getHibernateTemplate().save(entity); 5,AQ~_,'\
} ,f?#i%EF&
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publicvoid persist(finalObject entity){ z3*G(,
getHibernateTemplate().save(entity); =w A< F
} 0v7;ZxD
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publicvoid update(finalObject entity){ ]|`gTD6
getHibernateTemplate().update(entity); jPU#{Wo#
} L7Oytdc<
/#G"'U/
publicvoid delete(finalObject entity){ {t/!a0\HS
getHibernateTemplate().delete(entity); <M'IRf/D
} 9_>4~!x`
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publicObject load(finalClass entity, T4!]^_t^
qk,cp},2K
finalSerializable id){ qfYb\b
return getHibernateTemplate().load <Z8] W1)
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(entity, id); pO+1?c43
} 2FVKgyV
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publicObject get(finalClass entity, }ZmdX^xB
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finalSerializable id){ sId5pY!
return getHibernateTemplate().get aq5<Ks `r
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(entity, id); fA,+qs
} 5N/]/
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publicList findAll(finalClass entity){ E+1j3Q;
return getHibernateTemplate().find("from "tj#P
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" + entity.getName()); !F<?h e<U
} Awh"SUOh0
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publicList findByNamedQuery(finalString b<( W}$x
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namedQuery){ W"-nzdAJ5
return getHibernateTemplate Nz}Q"6L
kx=AX*I
().findByNamedQuery(namedQuery); .FXQ,7mZ-
} f.P( {PN
w%_BX3GTO
publicList findByNamedQuery(finalString query, kTk?[BK
H);'\]_'x
finalObject parameter){ <C>i~<`d
return getHibernateTemplate _(z"l"l=$
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().findByNamedQuery(query, parameter); B7 PmG
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} W_
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publicList findByNamedQuery(finalString query, )ED[cYGx
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finalObject[] parameters){ >Qx#2x+
return getHibernateTemplate "|G,P-5G"
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().findByNamedQuery(query, parameters); lhI;K4#
} I coL/7k3
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publicList find(finalString query){ %xfy\of+Nk
return getHibernateTemplate().find $"FdS,*qKl
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(query); }6bLukv
} piG1&*
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publicList find(finalString query, finalObject 1%@~J\qF
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parameter){ ~ 9;GD4
return getHibernateTemplate().find % *G)*n
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(query, parameter); 'AAY!{>
} fA8+SaXW%
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public PaginationSupport findPageByCriteria 3-R3Qlr
0hkuBQb\
(final DetachedCriteria detachedCriteria){ 3PA'Uk"5Z
return findPageByCriteria A%PPG+IfA
l17ZNDzLU
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 'JMa2/7CG
} $aA.d^
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public PaginationSupport findPageByCriteria *[5
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(final DetachedCriteria detachedCriteria, finalint HIq1/)
]2(c$R
startIndex){ eFio,
return findPageByCriteria @(cS8%wK
xB(:d'1|
(detachedCriteria, PaginationSupport.PAGESIZE, S2R[vB4).
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startIndex); `g1Oon_
} @EY}iK~
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public PaginationSupport findPageByCriteria I5L7BTe
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(final DetachedCriteria detachedCriteria, finalint Vi#im`@
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pageSize, lz (,;I'x
finalint startIndex){ %)9]dOdOk
return(PaginationSupport) L)}V[j#
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getHibernateTemplate().execute(new HibernateCallback(){ V</T$V$
publicObject doInHibernate >u)ZT
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(Session session)throws HibernateException { )!d1<p3
Criteria criteria = s.sy7%{
17cW8\
detachedCriteria.getExecutableCriteria(session); 6EU4
int totalCount = \vsrBM
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((Integer) criteria.setProjection(Projections.rowCount v)yimIHzo
.dCP8|
()).uniqueResult()).intValue(); u =kSs
criteria.setProjection 2]9<%-=S
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(null); IBkH+j
List items = HzV+g/8>A
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criteria.setFirstResult(startIndex).setMaxResults $-]setdY
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(pageSize).list(); 8 uxFXQ
PaginationSupport ps = 5{q/z^]
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new PaginationSupport(items, totalCount, pageSize, j#,M@CE
p^rX.?X
startIndex); ~5uNw*H
return ps; 6wB>-/'Y
} 0NtsFPO
}, true); ]&U| d
} ZPsY0IzLo
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public List findAllByCriteria(final Ro]IE|Fv
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DetachedCriteria detachedCriteria){ iwJ-<v_:h
return(List) getHibernateTemplate eH
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().execute(new HibernateCallback(){ W<91m*
publicObject doInHibernate &PuJV + y
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(Session session)throws HibernateException { THgzT\_zq
Criteria criteria = `U_>{p&x
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detachedCriteria.getExecutableCriteria(session); !otq
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return criteria.list(); HoE.//b
} R9/xC7l@
}, true); K}`p_)(
} hS{
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public int getCountByCriteria(final y/I~x+y
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DetachedCriteria detachedCriteria){ J+ZdZa}Ob
Integer count = (Integer) 'lsq3!d.
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getHibernateTemplate().execute(new HibernateCallback(){ yr9A0F0
publicObject doInHibernate |C6(0fgWd
.cS,T<$
(Session session)throws HibernateException { 0aTbzOn&
Criteria criteria = G\N"rG =
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detachedCriteria.getExecutableCriteria(session); @GZa:(
return ~oA9+mT5
}t
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criteria.setProjection(Projections.rowCount 8N*
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liw 9:@+V
()).uniqueResult(); +'j*WVE%5
} OO\biYh o
}, true); /Np"J
return count.intValue(); b/,!J]W
} 8^/Ek<Qb|
} O;BMwg_7
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用户在web层构造查询条件detachedCriteria,和可选的 vYR=TN=Z4
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startIndex,调用业务bean的相应findByCriteria方法,返回一个
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PaginationSupport的实例ps。 mGpkM?Y"
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ps.getItems()得到已分页好的结果集 h}`&]2|]
ps.getIndexes()得到分页索引的数组 Pv %vx U
ps.getTotalCount()得到总结果数 KT;C RO>
ps.getStartIndex()当前分页索引 2@m(XT
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ps.getNextIndex()下一页索引 %{~mk[d3
ps.getPreviousIndex()上一页索引 -?w v}o
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 YNgR1:l
9 CK\tx&
,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 OwiWnS<
gvc'
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一下代码重构了。 v>y8s&/
@t;O"q'|
我把原本我的做法也提供出来供大家讨论吧: ?9zoQ[
sx( l
首先,为了实现分页查询,我封装了一个Page类: z^!A/a[[!
java代码: j&[3Be'pQ
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8~s-t
/*Created on 2005-4-14*/ dy6F+V\DG
package org.flyware.util.page; i5E:FS^!I
iVpA@p
/** g?A5'o&Yu
* @author Joa Sp`fh7d.(
* dJQ }{,+6
*/ mWN1Q<vn,l
publicclass Page { *@G(3 n
^{fi^lL=
/** imply if the page has previous page */ 4-d99|mv
privateboolean hasPrePage; zN)|g
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/** imply if the page has next page */ Xs%R]KOwt
privateboolean hasNextPage; yNqm]H3<MP
# McK46B z
/** the number of every page */ X$uz=)
privateint everyPage; N1+4bR
r>Qyc
/** the total page number */ rq'##`H
privateint totalPage; im4e!gRE
.sJys SA\
/** the number of current page */ 0.u9f`04
privateint currentPage; TM/|K|_
iB}LnC:
/** the begin index of the records by the current S4 k^&$;
36^C0uNdX
query */ 9&XV}I,~?|
privateint beginIndex; MgH1d&R
K.V!@bPlw9
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/** The default constructor */ hk"9D<&i>b
public Page(){ 0$f_or9T
J/]o WC`u
} `u p-m=zA
9N*S-Po=
/** construct the page by everyPage >p]WCb'PH
* @param everyPage L.IoGUxD
* */ B~V<n&<
public Page(int everyPage){ 75\RG+kQ
this.everyPage = everyPage; 4+/fP
} x ^M5D+o
0gv3v@QO
/** The whole constructor */ j'#jnP*P
public Page(boolean hasPrePage, boolean hasNextPage, \'s$ZN$k
xJ=ZQ)&]
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int everyPage, int totalPage, 2<y}91N:
int currentPage, int beginIndex){ n!kk~65|
this.hasPrePage = hasPrePage; PuCwdTan_
this.hasNextPage = hasNextPage; u5cVz_S
this.everyPage = everyPage; To# E@Nw
this.totalPage = totalPage; LY\ddI*s
this.currentPage = currentPage; KlVi4.]
this.beginIndex = beginIndex; >YJ8u{Z{o
} #uD)0zdw
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/** G!!-+n<
* @return #RR:3ZPZC
* Returns the beginIndex. HsjELbH
*/ e'k;A{Oh
publicint getBeginIndex(){ ueWR/
return beginIndex; %jbJ6c
} *2 qh3
&jXca| wAR
/** 629~Uc6]
* @param beginIndex Wz6]*P`qv
* The beginIndex to set. xecieC
*/ m0xJ05Zx
publicvoid setBeginIndex(int beginIndex){ >G-8FL
this.beginIndex = beginIndex; PZ
} )XmCy"xx
pgz:F#>
/** klK-,J
* @return #;\L,a|>*
* Returns the currentPage. p|&ZJ@3
*/ P[Y{LKAbb
publicint getCurrentPage(){ $'A4RVVT
return currentPage; O3^98n2
} ^ [X|As2
u"`5
/** {\vI9cni|"
* @param currentPage :DOr!PNA
* The currentPage to set. o9KyAP$2
*/ 4c5^7";P
publicvoid setCurrentPage(int currentPage){ l?[{?Luq
this.currentPage = currentPage; itqQ)\W
} 90
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/** ri/t(m^{W
* @return w8AJ#9W
* Returns the everyPage. wb(*7 &eP:
*/ nuf@}W>y
publicint getEveryPage(){ Q `e~MD
return everyPage; @wd!&%yzO
} :3111}>c
~pHJ0g:t
/** EzzTJ>
* @param everyPage 2x-'>i_|g
* The everyPage to set. a~8:rW^
*/ qiG]nCq
publicvoid setEveryPage(int everyPage){ %/{IssCR7
this.everyPage = everyPage; MZCL:#
} .@y{)/
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/** ,bB( 24LD
* @return Si#"Wn?|
* Returns the hasNextPage. o\_
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*/ %iK%$
publicboolean getHasNextPage(){ Pk$}%;@v
return hasNextPage; W0VA'W
} D3<IuWeM
>}ro[x`K
/** <T(s\N5B=
* @param hasNextPage =}~NRmmF
* The hasNextPage to set. I["F+kt^^
*/ e(?:g@]-r
publicvoid setHasNextPage(boolean hasNextPage){ 6?53q e
this.hasNextPage = hasNextPage; GLo\q:5A
} BhqhyX\D&y
sFbfFUd
/** $a`J(I
* @return z[WC7hvU
* Returns the hasPrePage. pp/#Am
*/ J)-T:.i|0
publicboolean getHasPrePage(){ ?F!EB4E\y}
return hasPrePage; .i
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} 5,F;j<F
Bj;\mUsk
/** }*?yHJ3
* @param hasPrePage Lf5%M|o.)
* The hasPrePage to set. nVz5V%a!\q
*/ \9046An
publicvoid setHasPrePage(boolean hasPrePage){ m,\i
this.hasPrePage = hasPrePage; x^zdTMNhw
} I)[`ZVAXR
IO}+[%ptc*
/** ;l$9gD>R
* @return Returns the totalPage. uK$=3[;U/!
* dVvZu% DFp
*/ 9OPK4-
publicint getTotalPage(){ v2IEJ
return totalPage; 5iP8D<;o5
} bBA$}bv
)J;ny!^2
/** 6a7vlo
* @param totalPage [m~b[ZwES
* The totalPage to set. fr8Xoa%1=
*/ H":/Ckok
publicvoid setTotalPage(int totalPage){ q_-ma_F#s
this.totalPage = totalPage; 7*+Km'=M
} YkSuwx@5_q
ZH\0=l)
} @/9>=#4c
3.(.*>
L_E^}^1!
xcHen/4X
D0f*eSXE{
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 )X7e$<SU*
:M@MmpPh
个PageUtil,负责对Page对象进行构造: 64?Pfir6
java代码: `+oV/:Q3
b2G2 cL-(
g4Y) Bz
/*Created on 2005-4-14*/ iOl%-Y
package org.flyware.util.page; ' Q\ @19
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M!(
import org.apache.commons.logging.Log; >H$;Z$o*(
import org.apache.commons.logging.LogFactory; o1e4.-xI
FX7M4t#<
/** >J.Qm0TY(
* @author Joa <F ew<r2
* -<|Y 1PQ
*/ {z=j_;<]
publicclass PageUtil { Ah*wQow
7LG+$LEz
privatestaticfinal Log logger = LogFactory.getLog mU>&ql?e
+a #lofhv
(PageUtil.class); )^&,Dj
Jff 79)f
/** Bw6 L;Vu
* Use the origin page to create a new page ;xhOj<:
* @param page y">fN0{<
* @param totalRecords `n6/ A)
* @return Sobtz}A*
*/ 2%5?Fn=
publicstatic Page createPage(Page page, int %Mh Q
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totalRecords){ .xEJaID\N
return createPage(page.getEveryPage(), `-o5&>'nf
{>/)5AGs
page.getCurrentPage(), totalRecords); &2Q*1YXj
} R'L?Xn}3
{H+?z<BF<
/** J,RDTXqn
* the basic page utils not including exception !I~C0u
n3'dLJH|
handler lw s(/a*c
* @param everyPage Vd21,~^>g
* @param currentPage sllzno2bU
* @param totalRecords ]dq5hkjpU
* @return page 8-ZUS|7B
*/ @^'$r&M
publicstatic Page createPage(int everyPage, int wDMjk2YN
Ssw&'B|o
currentPage, int totalRecords){ +tIz[+u
everyPage = getEveryPage(everyPage); kffZElV
currentPage = getCurrentPage(currentPage); V'j@K!)~xR
int beginIndex = getBeginIndex(everyPage, 9_GokU P_
yQ'eu;+]
currentPage); ;@9e\!%
int totalPage = getTotalPage(everyPage, N};t<Xev
qJ
95
totalRecords); BMpF02Y|4
boolean hasNextPage = hasNextPage(currentPage, .A(i=!{q
|:N>8%@6c
totalPage); *
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boolean hasPrePage = hasPrePage(currentPage); 9s(i`RTM
[A]Ca$':
returnnew Page(hasPrePage, hasNextPage, Rjq a_hxrS
everyPage, totalPage, %J _ymJ'pd
currentPage, i|S:s
p0Gk j-
beginIndex); +RS$5NLH
} 5KJ%]B(H2
5/ * >v
privatestaticint getEveryPage(int everyPage){ VRF6g|0;
return everyPage == 0 ? 10 : everyPage; t7bqk!6hM\
} SRItE\"Xe
ei|cD[
NY
privatestaticint getCurrentPage(int currentPage){ rGQ5l1</
return currentPage == 0 ? 1 : currentPage; @; ;G88=
} )&,K94
doM?8C#`
privatestaticint getBeginIndex(int everyPage, int \Tyf *:_F>
1Cv#nhmp
currentPage){ g_vm&~U/'
return(currentPage - 1) * everyPage; GD&htob(
} ZE
rdt:w
/&(1JqzlB
privatestaticint getTotalPage(int everyPage, int e #M iaX
+I@cO&CY|
totalRecords){ {p]=++
int totalPage = 0; G mA!Mo
U-g9C.
if(totalRecords % everyPage == 0) yUe+":7k.
totalPage = totalRecords / everyPage; =Dk7RKoHF
else t8/%Dgu
totalPage = totalRecords / everyPage + 1 ; yj
zK.dM
~RInN+N#
return totalPage; @VK6JjIq
} ZdH1nX(Yh3
/c#l9&,
privatestaticboolean hasPrePage(int currentPage){ ! Mo`^t
return currentPage == 1 ? false : true; LG&5VxT=,<
} TBnvV 5_
;&
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privatestaticboolean hasNextPage(int currentPage, 9B=1Yr[
C
) ?uE'
int totalPage){ Kt6>L5:94
return currentPage == totalPage || totalPage == YE\K<T
jH
H\#:,s {1
0 ? false : true; ,r`UBQ}?
} f4"4ZVcr
.6m_>Y6
f{ ^:3"i
} iSiDSeW8
rwgsXS8W6
,Sg33N?
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mmP U
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 L/i(KF{
ARWZ; GX
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 *
t!r@k
vv+J0f^
做法如下: ,{KCY[}|
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 +EkW>$
sV2iITFp
的信息,和一个结果集List:
;:OsSq&
java代码: FN?3XNp.
`R+,1"5 =
[@G`Afaf
/*Created on 2005-6-13*/ "U8S81'
package com.adt.bo; ^npJUa
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import java.util.List; jg_n 7
@Y-TOCadT
import org.flyware.util.page.Page; S_\
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/** x8"#!Pw:`"
* @author Joa F8=nhn
*/ c!wtf,F
publicclass Result { cj
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Fo}7hab
private Page page; _Y!sVJ){,c
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private List content;
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ST;t,
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/** &&7r+.Y
* The default constructor Z<"K_bj
*/ > 0.W`j(s
public Result(){ dR+1aY;
super(); 4!%F\c46
} B42sb_
zwr\:Hu4
/** "b,%8
* The constructor using fields +iA=y=;blH
* NXU`wnVJ
* @param page v(O=IUa
* @param content `hrQw)5?r
*/ XvKFPr0~
public Result(Page page, List content){ GwLFL.Ke
this.page = page; o#D.9K(
this.content = content; GoE
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} 4c159wsnQ
8C7Z{@A
/** Qh`:<KI
* @return Returns the content. LFu%v7L`
*/ `i fiL
publicList getContent(){ ao$.6X8fQ
return content; ;t(f1rPyE
} qf8[!5GM
S$[k Q|Am
/** 0rE(p2
* @return Returns the page. NlF}{
*/ 'q{733o
public Page getPage(){ Vrp[r *V@E
return page; J4aBPq`
} q_t4OrLr=
?c#$dc"
/** ,pt%)
c
* @param content 8;" *6vHZ
* The content to set. (^n*Am;zlH
*/ 51xk>_Hm}|
public void setContent(List content){ #T3h}=
this.content = content; 11UB4CA
} tIuoD+AW
nII^mg~
/** <@uOCRbV
* @param page la^
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* The page to set. vkcRm`.
*/ ]}PV"|#K{c
publicvoid setPage(Page page){ %2l7Hmp4H
this.page = page; uT_!'l$fr
}
!#x= JX
} !GK$[9
ra6o>lI(,
" I+p
~;#MpG;e
,mFsM!|
2. 编写业务逻辑接口,并实现它(UserManager, csQfic
xWX*tJ4
UserManagerImpl) eon!CE0
java代码: b ,^*mx=
0$P/jt
buMqF-j
/*Created on 2005-7-15*/ Q^_/By@
package com.adt.service; C"w
{\
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Ru\_dr2yI}
import net.sf.hibernate.HibernateException; kQv*eZ~
!Pj/7JC0
import org.flyware.util.page.Page; }1H=wg>\
V H^AcO
import com.adt.bo.Result; A(d5G^
ktH8as^54!
/** g:#dl\k
* @author Joa !<\Br
*/ v"Jgw;3
publicinterface UserManager { 5OP`c<
lWZuXb,G
public Result listUser(Page page)throws (ywo
a
#-#NqX:
HibernateException; Qx`~g,wk8
!|G(Yg7C
} (lH,JX`$a
USPTpjt8R
ANMg
~H /2R
+M\8>/0oA
java代码: k9si|'
e [0w5)X
Ff4*IOZ}(
/*Created on 2005-7-15*/ j
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package com.adt.service.impl;
>'=MH2;
%{5n1w
import java.util.List; <,1fkq>,
C;rG]t^%
import net.sf.hibernate.HibernateException; KFWJ}pNq
+a+`Z>
import org.flyware.util.page.Page; Ob<W/-%5tH
import org.flyware.util.page.PageUtil; `NNf&y)y
)Hw:E71h2
import com.adt.bo.Result; UWXm?v2j
import com.adt.dao.UserDAO; 7"v$- W y
import com.adt.exception.ObjectNotFoundException; -w6
"?
import com.adt.service.UserManager; yJ2B3i@T4
4&X*pL2;
/** g /+oZU
* @author Joa WE!vSZ3R
*/ 'c`jyn
publicclass UserManagerImpl implements UserManager { vK'?:}~
;[0&G6g
private UserDAO userDAO; ;3ft1
/CX VLl8~
/** {padD p
* @param userDAO The userDAO to set. `$RA< 3
*/ rAqxTdF
publicvoid setUserDAO(UserDAO userDAO){ {I1~-8
this.userDAO = userDAO; ]]iPEm"@
} WQePSU
}iN2KeLAF
/* (non-Javadoc) 9@VO+E$7L
* @see com.adt.service.UserManager#listUser HK=[U9 o?
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(org.flyware.util.page.Page) ' [0AHM
*/ d]v+mVAyE
public Result listUser(Page page)throws /Wj,1WX~
m6n!rRQ^U
HibernateException, ObjectNotFoundException { i76 Yo5
int totalRecords = userDAO.getUserCount(); ?pGkk=,KB
if(totalRecords == 0) 3`V1XE.;
throw new ObjectNotFoundException O/Y)&VG7
(M-ZQ
-
("userNotExist"); z4U9n'{
page = PageUtil.createPage(page, totalRecords); %}Q&1P=
List users = userDAO.getUserByPage(page); }=}>9DSM
returnnew Result(page, users); m~l
F`?
} df*w>xS
rP=sG;d
} 773/#c
{bNXedZ\
omX?Bl
8\ha@&p
QBJ3iQs1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 j6}R7$JR
ZU&"73
询,接下来编写UserDAO的代码: 90N`CXas
3. UserDAO 和 UserDAOImpl: Wsj=!Obc
java代码: j
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n-;y*kD
W0`Gc
{
/*Created on 2005-7-15*/ H: {7X1bV
package com.adt.dao; Xh+ia#K
hZ\+FOx;
import java.util.List; 8nNsrat
QL7>;t;
import org.flyware.util.page.Page; Hgc=M
Oxx^[ju~
import net.sf.hibernate.HibernateException; ,w)p"[^b
,d,\-x-+/
/** $a;]_ Y
* @author Joa 'Pltn{iq[
*/ MQ/
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publicinterface UserDAO extends BaseDAO { adEJk
q 2?X"!
publicList getUserByName(String name)throws 6vzk\n
\>/M .2
HibernateException; HRa@
T5lQIr@a
publicint getUserCount()throws HibernateException; xycH~ ?
Z+:D)L
publicList getUserByPage(Page page)throws [Gr*,nVvB
y6HuN
HibernateException; tJI,r_
w5C*L)l
} BNGe
exs@
WgR4Ix^L#
*<V^2z$y_
3yS
ni CE\B~
java代码: Lm)\Z P+W
5 MxL*DB=b
@$@mqHI}
/*Created on 2005-7-15*/ 3NK ^AaTK
package com.adt.dao.impl; =(r*
5vd
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import java.util.List; pa
.K-e)Mu
eARk
QV
import org.flyware.util.page.Page; ZDLMMXx>
MFit|C
import net.sf.hibernate.HibernateException; ;^k7zNf-
import net.sf.hibernate.Query; o,Z{ w"
*iXe^ <6v
import com.adt.dao.UserDAO; N> Jw
%Q|eiXD
/** obClBO)@Y
* @author Joa EmVuwphv
*/ 2-If]Fc
public class UserDAOImpl extends BaseDAOHibernateImpl ]hw-Bu\{
'{?C{MK3Q
implements UserDAO { YhKZ|@
NY
/* (non-Javadoc) FpV`#6i7
* @see com.adt.dao.UserDAO#getUserByName YrI|gz)
US&B!Q:v
(java.lang.String) 5CYo7mJ6+
*/ 43:t
\
publicList getUserByName(String name)throws V-O(U*]
CX/(o]
HibernateException { D}mL7d1
String querySentence = "FROM user in class <_S@6?
|lQ;ALH!
com.adt.po.User WHERE user.name=:name"; {kB `>VS
Query query = getSession().createQuery G&{HTYP
| FM
}
(querySentence); %B2XznZ:
query.setParameter("name", name); |!z2oO
return query.list(); cL7g}$W$
} aC=['a>)
~Vh =5J~
/* (non-Javadoc) my\&hCE
* @see com.adt.dao.UserDAO#getUserCount() Iq5pAHm>M6
*/ b}z`BRCc
publicint getUserCount()throws HibernateException { .#6MQJ]OH
int count = 0; RNJFSD.
String querySentence = "SELECT count(*) FROM Va<HU:<
jRZ%}KX
user in class com.adt.po.User"; 0NE{8O0;Fr
Query query = getSession().createQuery ~ 9o6 W",
lPq\=V
(querySentence); oY9FK{
count = ((Integer)query.iterate().next $Rtgr{ {;"
z5cYyx
r>
()).intValue(); {aq9i
return count; @uleyB
} 3 x*z\VJ
0~A#>R'
/* (non-Javadoc) |w&~g9
* @see com.adt.dao.UserDAO#getUserByPage uGtV}-t:
H?rg5TI0
(org.flyware.util.page.Page) L&2u[ml
*/ fjz) Gp
publicList getUserByPage(Page page)throws 7ETjn)%bs
GuQRn
HibernateException { %uDG75KP{
String querySentence = "FROM user in class Gm8E<iTP
pK_?}~
com.adt.po.User"; TR vZ
Query query = getSession().createQuery cgZaPw2
bw
D@54QJ<
(querySentence); J\co1kO9/
query.setFirstResult(page.getBeginIndex()) n@>wwp
.setMaxResults(page.getEveryPage()); -AD2I {C
return query.list(); V^fV7hw<
} :-+4:S
S'i;xL>
} kT oOIx
{ISE'GJj
I<\
'%
zQ)+/e(8
70gg4BS
至此,一个完整的分页程序完成。前台的只需要调用 oVO.@M#
lu\o`m5wF
userManager.listUser(page)即可得到一个Page对象和结果集对象 Iin#Wd-/
b{[*N
的综合体,而传入的参数page对象则可以由前台传入,如果用 4SVW/Zl.?
Di(9]:+
webwork,甚至可以直接在配置文件中指定。 :b#%C
pR
Cnh|D^{s
下面给出一个webwork调用示例: ,Qc.;4s-
java代码: 7XAvd-
IM(u<c$
e<+<lj"
/*Created on 2005-6-17*/ !c(QSf502
package com.adt.action.user; ~1 ZD[@
b5`KB75sbo
import java.util.List; c. K =(y*
nYw\'c
import org.apache.commons.logging.Log; W4(?HTWZ
import org.apache.commons.logging.LogFactory; )m#']c:rg
import org.flyware.util.page.Page; fj']?a!m
?T'][q
import com.adt.bo.Result; 2W$lQ;iO
import com.adt.service.UserService; SG]K
import com.opensymphony.xwork.Action; WStnzVe
EQ
>t[ &
/** '1+.t$"/tU
* @author Joa "Ai6<