Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 pV[SY6/
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1K\zamBg
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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 DXyRNE<G[C
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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 [+;>u|
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分页支持类: ((Uw[8#2`
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java代码: ;V v.$mI
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package com.javaeye.common.util; vLI'Z)\
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import java.util.List; -RI&uFqOI
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publicclass PaginationSupport { 4m1@lnjp
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publicfinalstaticint PAGESIZE = 30; yo^M>^P\N
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privateint pageSize = PAGESIZE; >v#6SDg
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privateList items; hik.c3
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privateint totalCount; 6v?tZ&,
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privateint[] indexes = newint[0]; .VXadgM
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privateint startIndex = 0; b]5/IT)@O
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public PaginationSupport(List items, int Mh"iyDGA
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totalCount){ bUU\bc
setPageSize(PAGESIZE); br;~}GR_h
setTotalCount(totalCount); .C|dGE?,
setItems(items); yU|=)p5
setStartIndex(0); fL(_V/p^
} O%s7 }bR3
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public PaginationSupport(List items, int dt5`UBvUg
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totalCount, int startIndex){ VV-%AS6;
setPageSize(PAGESIZE); HC!5AJ&+}v
setTotalCount(totalCount); 7<0oK|~c#
setItems(items);
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setStartIndex(startIndex); @+>t]jyz
} s{uSU1lQn
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public PaginationSupport(List items, int JuDadIrd{
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totalCount, int pageSize, int startIndex){ EG!Nsb^,
setPageSize(pageSize); Ex<@:
setTotalCount(totalCount); yYH>~,
setItems(items); w!r.MWE
setStartIndex(startIndex); G?+0#?'Y
} ~P fk
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publicList getItems(){ w&eq
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return items; *4y0Hq
} ?>Bt|[p:s)
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publicvoid setItems(List items){ '$h0l-mQ
this.items = items; 0ky3rFSh1
} 1VA%xOURh
m`&6[[)6~
publicint getPageSize(){ uWLf9D "
return pageSize; Z x&= K"
} Ow0( q^H<
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publicvoid setPageSize(int pageSize){ KBI36=UV
this.pageSize = pageSize; NQx>u
} =zW`+++3
@NYlVk2
publicint getTotalCount(){ wvI}|c
return totalCount; (V>/[Ev
} x-T7
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publicvoid setTotalCount(int totalCount){ 1`2lq~=GV
if(totalCount > 0){ G&q@B`I
this.totalCount = totalCount; :gM_v?sy
int count = totalCount / Rhzcm`"
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pageSize; {#N,&?[
if(totalCount % pageSize > 0) g$U7bCHG
count++; 5Z_aN|Xn
indexes = newint[count]; fBLR
for(int i = 0; i < count; i++){ b\vL^\bX8
indexes = pageSize * mW)C=X%
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} b
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}else{ :+<GJj_d+
this.totalCount = 0; i9^m;Y)^I
} snVeOe#'S
} m^;A]0h+
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publicint[] getIndexes(){ Q[.d
return indexes; e0g>.P@6
} m88[(l
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publicvoid setIndexes(int[] indexes){ \GCT3$
this.indexes = indexes; ;m}o$`
} Fv3:J~Yf
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publicint getStartIndex(){ ;'oi7b
return startIndex; 71G00@&w9D
} ~2}^
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publicvoid setStartIndex(int startIndex){ yHxi^D]
if(totalCount <= 0) 1-}$sO c
this.startIndex = 0; ~p$ncIr2Q
elseif(startIndex >= totalCount) oI9-jW
this.startIndex = indexes *Edr\P
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[indexes.length - 1]; E akS(Q?
elseif(startIndex < 0) 'p4b8:X
this.startIndex = 0; l 5z8]/
else{ C<hb{$@
this.startIndex = indexes _R;+}1G/
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[startIndex / pageSize]; 0u8(*?
} K9Bi2/N
} ?]2OT5@&s
@-BgPDi.Z
publicint getNextIndex(){ E']Gh
int nextIndex = getStartIndex() + 9p9-tJfH.
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pageSize; }$1Aw%p^
if(nextIndex >= totalCount) Gq^#.o]
return getStartIndex(); <=&7*8u0+
else G+l9QaFv
return nextIndex; +ywd(Tuzm
} eE[/#5tK
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publicint getPreviousIndex(){ -cnlj
int previousIndex = getStartIndex() - *!x/ia9
bHH=MLZR:
pageSize; .@;,'Xw1~
if(previousIndex < 0) >jBnNA@
return0; o!M*cyq
else AZadNuL/
return previousIndex; T#w *5Qf
} d^jIsE `
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} N>_d {=P
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抽象业务类 &_y+hV{
java代码: =Pgu?WU@
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/** "rIBy
* Created on 2005-7-12 o'nrLI(t
*/ hy|X(m
package com.javaeye.common.business; 2-M]!x)
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import java.io.Serializable; D^H<)5d9
import java.util.List; vH^^QI:em
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import org.hibernate.Criteria; ~+Da`Wp
import org.hibernate.HibernateException; wuTCdBu6hU
import org.hibernate.Session; yD!V;?EnK
import org.hibernate.criterion.DetachedCriteria; J#y?^Qm$)<
import org.hibernate.criterion.Projections; ps6c>AN`A&
import "Z6: d"S`
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org.springframework.orm.hibernate3.HibernateCallback; VClw!bm
import RU'DUf
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org.springframework.orm.hibernate3.support.HibernateDaoS g1`/xJz|
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upport;
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import com.javaeye.common.util.PaginationSupport; (FAd'$lhX}
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public abstract class AbstractManager extends x 1"ikp}
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HibernateDaoSupport { ')w*c
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privateboolean cacheQueries = false; *ad"3>
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privateString queryCacheRegion; t9()?6H\
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publicvoid setCacheQueries(boolean -zVa[&
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cacheQueries){ ]-aeoa#
this.cacheQueries = cacheQueries; oa?eK
} :[N[D#/z
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publicvoid setQueryCacheRegion(String bMD'teJ
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queryCacheRegion){ >9g` 9hB
this.queryCacheRegion = pTK|u!fs
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queryCacheRegion; , &HZvU&
} ^"%SHs
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publicvoid save(finalObject entity){ r\"O8\
getHibernateTemplate().save(entity); RfwTqw4@
} sy`:wp
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publicvoid persist(finalObject entity){ ${ ~UA6
getHibernateTemplate().save(entity); 8E Y<^:
} 5 b[:B~J
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publicvoid update(finalObject entity){ O.E
getHibernateTemplate().update(entity); `B6{y9J6
} GfU+'k;9
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publicvoid delete(finalObject entity){ k[Iwxl;/
getHibernateTemplate().delete(entity); 8Db~OYVJG
} L/GM~*Xp(O
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publicObject load(finalClass entity, q9oF8&O,
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finalSerializable id){ =D4EPfQn1
return getHibernateTemplate().load LZG^\c$
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(entity, id); g}3c r.
} *ma/_rjK
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publicObject get(finalClass entity, K.R2)o`
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finalSerializable id){ [JVI@1T
return getHibernateTemplate().get ,/W<E
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(entity, id); ]+':=&+:
} );z}T0C
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publicList findAll(finalClass entity){ ;?2vW8{p<
return getHibernateTemplate().find("from AEnS_Q
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" + entity.getName()); ;.W0Aa
} {zUc*9
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publicList findByNamedQuery(finalString Whd4-pR8
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namedQuery){ Ai->,<Ig]
return getHibernateTemplate ;^DUtr
;
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().findByNamedQuery(namedQuery); ,mYoxEB kl
} !Y]}&pUP
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publicList findByNamedQuery(finalString query, <\^X,,WtO
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finalObject parameter){ YC=BP5^
return getHibernateTemplate R/^JyL
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().findByNamedQuery(query, parameter); X_'.@q<!CV
} 4&ea*w
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ {C]M]b*F6(
return getHibernateTemplate iW"L!t#\|
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().findByNamedQuery(query, parameters); -'PpY302
} 6eDIS|/
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publicList find(finalString query){ 4E
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return getHibernateTemplate().find ;7`<.y
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(query); -Ez|
} f6L_uk`{
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publicList find(finalString query, finalObject )i_FU~ LRq
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parameter){ J82{PfQ"
return getHibernateTemplate().find ~2H7_+.#
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(query, parameter); km c9P&
} Q"hI !PO+
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public PaginationSupport findPageByCriteria h{* O9O<
p fBO5Ys
(final DetachedCriteria detachedCriteria){ "ZyHt HAK
return findPageByCriteria P/I{q s
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @eTsS%f2
} Ar<OP'C
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public PaginationSupport findPageByCriteria K<]fElh-
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(final DetachedCriteria detachedCriteria, finalint .897Z|$VB
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startIndex){ g
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return findPageByCriteria rp'fli?0e
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(detachedCriteria, PaginationSupport.PAGESIZE, \PLV]%3,
<;6])
startIndex); b<F 4_WF
} bf74 "
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public PaginationSupport findPageByCriteria Nu_w@T\l
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(final DetachedCriteria detachedCriteria, finalint N9n1s2;o
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pageSize, `>sqP aD
finalint startIndex){ -ufmpq.
return(PaginationSupport) N6J$z\
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getHibernateTemplate().execute(new HibernateCallback(){ R&4E7wrdP
publicObject doInHibernate uf;q/Wr
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(Session session)throws HibernateException { m_(hCY=Q$
Criteria criteria = i52R,hz
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detachedCriteria.getExecutableCriteria(session); s^oNQ}
int totalCount = \9}5}X_x.
@qC:% |>
((Integer) criteria.setProjection(Projections.rowCount |?|
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()).uniqueResult()).intValue(); Iv<9})2K
criteria.setProjection z;/'OJ[.
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(null); 'QS"4EvdD
List items = ltrSTH,kL
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criteria.setFirstResult(startIndex).setMaxResults WvJ?e
e6R"W9
(pageSize).list(); pMB=iS<E
PaginationSupport ps = 7P`1)juA9
(Z$6JNkz
new PaginationSupport(items, totalCount, pageSize, &tgvE6/V
2:N_c\Vi
startIndex); 6g"<i}_|
return ps; qE{cCS
} <!N;(nZ9}O
}, true); _Y|kX2l
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} cik@QN<[0
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public List findAllByCriteria(final YxtkI:C?
{^f0RGJg9
DetachedCriteria detachedCriteria){ Q*C4
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return(List) getHibernateTemplate D9C}Dys
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().execute(new HibernateCallback(){ Qf|}%}%fp
publicObject doInHibernate 1hviT&
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(Session session)throws HibernateException { S1zw'!O5
Criteria criteria = 4sj%:
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detachedCriteria.getExecutableCriteria(session); IA^)`l 7H
return criteria.list(); 7S2F^,w
} |+:ZO5FaO
}, true); D%idlL2%J
} >>bYg
oPy zk7{
public int getCountByCriteria(final ]R{"=H'
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DetachedCriteria detachedCriteria){
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Integer count = (Integer) | q16%6q
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getHibernateTemplate().execute(new HibernateCallback(){ b(q&}60
publicObject doInHibernate mG~y8nUtp
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(Session session)throws HibernateException { -HsBV>C
Criteria criteria = zzQH@D1
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detachedCriteria.getExecutableCriteria(session); 6h_ k`z
return <e&QTyb
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criteria.setProjection(Projections.rowCount NydW9r:T
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()).uniqueResult(); Gr@{p"./z
} N`Xnoehu
}, true); *Z`eNz}
return count.intValue(); N#)VD\m
} G`#gV"PlC
} 4_%FSW8-
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用户在web层构造查询条件detachedCriteria,和可选的 +Jka :]MW!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 U9o*6`"o
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PaginationSupport的实例ps。 DsW`V~T
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ps.getItems()得到已分页好的结果集 RpK,ixbtA+
ps.getIndexes()得到分页索引的数组 7 3z
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ps.getTotalCount()得到总结果数 9H}iX0O
ps.getStartIndex()当前分页索引 .&x?`pER
ps.getNextIndex()下一页索引 -mHhB(Td'
ps.getPreviousIndex()上一页索引 /Tf*d>Yh;
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 D^s0EW-E
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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 c^Gwri4
ls"\YSq$
一下代码重构了。 FJ%R3N\
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我把原本我的做法也提供出来供大家讨论吧: !bV(VRbu
#8f"}>U9.,
首先,为了实现分页查询,我封装了一个Page类: .-u k
java代码: cevV<Wy+
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/*Created on 2005-4-14*/ DET!br'z5
package org.flyware.util.page; VtzmY
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/** YNJpQAuSn)
* @author Joa YTjuSV
* Cb%.C;q
*/ ;Jbc'V'fm
publicclass Page { Ul713Bjz
{8Jk=)(md
/** imply if the page has previous page */ <#p|z`N
privateboolean hasPrePage; -KwL9J4u
ilRm}lU|x
/** imply if the page has next page */ %QsSR'`
privateboolean hasNextPage; .xz,pn}
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/** the number of every page */ >_0 i=.\
privateint everyPage; Q"6hD?6.
#:vDBP05.m
/** the total page number */ qgC-@I
privateint totalPage; v_ nBh,2
K!D_PxV
/** the number of current page */ `/wq3+ ?
privateint currentPage; /,!7jF:
n#^?X
/** the begin index of the records by the current 6KCCbg/
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query */ >.O*gv/_
privateint beginIndex; ok>P [
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lGnql 1(
/** The default constructor */ ,'1Olu{v[s
public Page(){ a._^E/EV
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} V:(w\'wm
l\sS?
/** construct the page by everyPage 2 -p
* @param everyPage ycl>git]
* */ ]EVe@
public Page(int everyPage){ o3i,B),K
this.everyPage = everyPage; Xc9p;B>^Ts
} H81.p
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/** The whole constructor */ iA%'
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public Page(boolean hasPrePage, boolean hasNextPage, @!&Jgg53G
Y( V3PnH
LG Y!j_bD
int everyPage, int totalPage, _8x'GK
tU
int currentPage, int beginIndex){ p-i.ITRS
this.hasPrePage = hasPrePage; |auX*hb9
this.hasNextPage = hasNextPage; 1O]5/Eu
this.everyPage = everyPage; f1CMR4D
this.totalPage = totalPage; hP4)8 >
this.currentPage = currentPage; rAlh&
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this.beginIndex = beginIndex; {7K'<ti
} oc3dd"8}@
h=K36a)
/** e\^g|60f_
* @return w]W`R.
* Returns the beginIndex. PzMlua
*/ u8<&F`7j
publicint getBeginIndex(){ ;*wT,2;
return beginIndex; <*A|pns
} n?ZL"!$
:tjgg]
/** 409x!d~it
* @param beginIndex _UH/}!nqB
* The beginIndex to set.
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*/ un$ Z7W/
publicvoid setBeginIndex(int beginIndex){ T1Gp$l
this.beginIndex = beginIndex; GCP{Z]u
} [xZ/ZWb/
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dfhno;
/** y~==waZw
* @return 2,8/Cb
* Returns the currentPage. *l> [`U+
*/ ;T5,T
publicint getCurrentPage(){ 6Q.{llO
return currentPage; wO2V%v^bp
} r
1l/) ;
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/** 08Pt(kzNA
* @param currentPage ,Lt~u_ lve
* The currentPage to set. RjR&D?dc
*/ C@TN5?Z
publicvoid setCurrentPage(int currentPage){ {[M0y*^64$
this.currentPage = currentPage; o~OwE7H)A
} z`emKFbv
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/** `2B*CMW{
* @return p4m^ ~e
* Returns the everyPage. 1a($8>
*/ DEUd[
publicint getEveryPage(){ `G=ztL!gq
return everyPage; H4PbO/{xO
} toS(UM n
;Pol#0_(
/** p3M#XC_H]
* @param everyPage rxs~y{Xi
* The everyPage to set. Z&+NmOY4
*/ ZQ,fm`y\
publicvoid setEveryPage(int everyPage){ ~_DF06G
this.everyPage = everyPage; /<3;0~#){
} 54
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g9yaNelDh)
/** 0[n c7)sW
* @return JCcN>DtP
* Returns the hasNextPage. Hv8SYQ|
*/ ,s1&O`
publicboolean getHasNextPage(){ <^,o$b
return hasNextPage; `ir&]jh.A
} L#
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,N;))3
/** 'i@,~[Z4
* @param hasNextPage zW*}`S"
* The hasNextPage to set. vKcl6bVT
*/ 1% $d D2
publicvoid setHasNextPage(boolean hasNextPage){ &Q\_;
this.hasNextPage = hasNextPage; ! (2-(LgA
} 9
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!MZ+- dpK
/** RL?u n}Qa
* @return u]
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* Returns the hasPrePage. Ni+3b
*/ I#"t'=9H
publicboolean getHasPrePage(){ L8K0^~Mk
return hasPrePage; !UBy%DN~k
} jP1$qhp
bjPka{PBj
/** K^"w]ii=
* @param hasPrePage I\}|Y+C$d/
* The hasPrePage to set. z=ML(1c=
*/ 6BDt.bG
publicvoid setHasPrePage(boolean hasPrePage){ +68+PhHF
this.hasPrePage = hasPrePage; 2{Wo-B,wt~
} ~R :<Bw
7IA3q{P
/** V -q%r
* @return Returns the totalPage. E|pk.
* VLf
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*/ `@h:_d
publicint getTotalPage(){ m_c O<LB
return totalPage; M,crz
} ao)Ck3]
*f79=x
/** K1:a]aU?Iu
* @param totalPage :ar?0
* The totalPage to set. xKY$L*
*/ cvKV95bn
publicvoid setTotalPage(int totalPage){ uA~YRKer
this.totalPage = totalPage; y)6,0K {k
} NA+&jV
XR|"dbZW.0
} 3rxo,pX94
CXTt(-FT
kGpV;F==*
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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 'nMApPl
A^pu
个PageUtil,负责对Page对象进行构造: p?;-!TUv
java代码: ;_iPm?Y8
-<_7\09
ue@8voZhS/
/*Created on 2005-4-14*/ I[ai:
package org.flyware.util.page; HeCcF+
[_h%F,_ A
import org.apache.commons.logging.Log; SC'BmR"ox
import org.apache.commons.logging.LogFactory; 8)sg_JC
t)ld<9)eB
/** O:1DOUYXs
* @author Joa kGm:VYf%
* DR6]-j!FK
*/ "9qp"%
publicclass PageUtil { =HMmrmz:
Gfv(w=rr?
privatestaticfinal Log logger = LogFactory.getLog Kh)FyV
k5a\Sq}
(PageUtil.class); }&1Iyb
job[bhK'Jt
/** co/7l sW
* Use the origin page to create a new page VpSEVd:n
* @param page *xcP`
* @param totalRecords k^^:;OR
* @return uArR\k(
*/ MHo1 lrZa+
publicstatic Page createPage(Page page, int [h4o7
=D].`
totalRecords){ ~Eq \DK
return createPage(page.getEveryPage(), J='W+=N
0N{+y}/G
page.getCurrentPage(), totalRecords); i&A%"lOI9
} XvskB[\
.|uLt J
/** 5@ foxI
* the basic page utils not including exception :M j_2
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handler Q2eXK[?*
* @param everyPage kJk xx*:u
* @param currentPage t8&q9$
* @param totalRecords Jf)3< ~G
* @return page
: tM?%=Q
*/ b{RqwV5P
publicstatic Page createPage(int everyPage, int ?U_9{}r
~GG?GB
currentPage, int totalRecords){ Gy!P,a)z
everyPage = getEveryPage(everyPage); bD<qNqX$
currentPage = getCurrentPage(currentPage); }E; F)=E
int beginIndex = getBeginIndex(everyPage, S5_t1wqBJ
wVqd$nsY"
currentPage); :
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int totalPage = getTotalPage(everyPage, bC~~5Cm
Fc8E Y*
totalRecords); JDv-O&]
boolean hasNextPage = hasNextPage(currentPage, ?+r!z
$b>}C= gt
totalPage); HM&1yubh#
boolean hasPrePage = hasPrePage(currentPage); qzK("d
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eE{
returnnew Page(hasPrePage, hasNextPage, /APcL5:=
everyPage, totalPage, wGJjA=C
currentPage, knT.l"
5j eO"jB
beginIndex); ]` ]g@v
} =Ikg.jYq&F
kq-6HDR
privatestaticint getEveryPage(int everyPage){ e"Rm_t
return everyPage == 0 ? 10 : everyPage; DA"}A`HfI
} @T&t.|`
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privatestaticint getCurrentPage(int currentPage){ =MLf[
return currentPage == 0 ? 1 : currentPage; XoR>H4xh
} \k@Z7+&7
dB;3.<S=
privatestaticint getBeginIndex(int everyPage, int "&lN\&:
Z0ReWrl;`
currentPage){ )ofm_R'q*
return(currentPage - 1) * everyPage; #tjmWGo,
} t`G)b&3_O
:eOR-}p'
privatestaticint getTotalPage(int everyPage, int #SkX@sl@
8g*hvPc
totalRecords){ *7" L]6
int totalPage = 0; 4_LQ?U>$
:?CQuEv-
if(totalRecords % everyPage == 0) Y
?'tUV
totalPage = totalRecords / everyPage; &Un6ay
else PuXUuJx(
totalPage = totalRecords / everyPage + 1 ; :Q@)*kQH
/smiopFcq
return totalPage; 5H lWfD
} ksWSMxm
[vTMS2
privatestaticboolean hasPrePage(int currentPage){ q0O&UE)6Y
return currentPage == 1 ? false : true; lKKERO5+
} 'r+PH*Mr
zgKY4R{V
privatestaticboolean hasNextPage(int currentPage, v-`h>J!Nx
dDtFx2(R
int totalPage){ 9"sDm}5%
return currentPage == totalPage || totalPage == t`|,6qEG
V U~Dk);Bv
0 ? false : true; $h28(K%
} "0&N}
G'x .NL
E\{< ;S
} vR>o}%`
z`$J_Cj Y
#S5`Pd!I
;sPzOS9
#[ -\lU|
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。 @5<CXTdF9c
N/~N7MwJj
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 [!"XcFY:a
%<Q*Jf
做法如下:
27 GhE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 cA;js;x@
uDuF#3
+"
的信息,和一个结果集List: 1u}nm;3
java代码: ^_>!B)
orIQ~pF#
jo98
jA<
/*Created on 2005-6-13*/ \u{8Bak0
package com.adt.bo; SEF6B45}1
\#dl6:"
import java.util.List; Q M1F?F
F#V q#|_)>
import org.flyware.util.page.Page; {G*QY%j^
GsV4ZZ
/** u oVNK
* @author Joa 6Nh0
*/ d^V$Z6*
]
publicclass Result { E9 Y\X
9=+-QdX+0]
private Page page; WZFH@I28
1BTIJ G w
private List content; }zMf7<C
B|o%_:]+E
/** >a>fb|r
* The default constructor {0yu
*/
Xm_$
dZ
public Result(){ BWUq%o,@g
super(); G '#41>q+
} g9mG`f
Hs?zq
/** F^kwdS
* The constructor using fields &%F@O<:
* 30F!kP*E
* @param page wu~hqd
* @param content ?S#\K^
*/ 8+'C_t/0i
public Result(Page page, List content){ \m/xV/
this.page = page; 4$"DbaC
this.content = content; uV]ULm#,i
} ",B'k
;b%{ilx:
/** %mI~
=^za
* @return Returns the content. *\XH+/]+
*/ RtV.d\
publicList getContent(){ FY#!N
L
return content; =@r--E
} qfL-r,XS`F
d*]Ew=^L
/** pyB~M9Bp/
* @return Returns the page. S GcBmjP
*/ N{joXHCu
public Page getPage(){ .;I29yk\XS
return page; ;;&F1@3tBa
} y?z\L
\0*l,i1&
/** XGs^rIf
* @param content &Cro2|KZhG
* The content to set. zg}YGu|J
*/ 6Wf^0ok
public void setContent(List content){ zV.pol
this.content = content; @h9MxCE!
} cCdX0@hY
}NmNanW^
/** |X (2Zv^O
* @param page /Jlv"R1,
* The page to set. eti`O
*/ 'jaoO9KY
K
publicvoid setPage(Page page){ 1~5trsB+5
this.page = page; G$JFuz)|
} oRY!\ADR
} jX
*/piSq
/oP^'""@je
:BZ0 7`9
)iLM]m
D-ADv3E,
2. 编写业务逻辑接口,并实现它(UserManager, I4e+$bU3
t@B(+
UserManagerImpl) l},NcPL`
java代码: gA^q^>7
8b&uU [
, Ww
/*Created on 2005-7-15*/ (H#M<N
package com.adt.service; &=q! Wdw~
_a
-]?R
import net.sf.hibernate.HibernateException; IB$7`7
jj&s}_75
import org.flyware.util.page.Page; tJZc/]%`H
'ZHdV,dd
import com.adt.bo.Result; T[uDZYx
9O98Q6-s
/** F]=B'ZI
* @author Joa O6c\KFBSJ
*/ isK;mU?<
publicinterface UserManager { ~L?nq@DL
QZYU0;
VF
public Result listUser(Page page)throws *Xr$/N
zK5bO=0j
HibernateException; =nRuY'
}C#3O{5
} oyeG$mpg
YD_]!HK}
%'ZN`XftG
< o I8-f
AXW!]=?X
java代码: n Wgv~{,x
]7/gJ>g,
P]6}\
]~
/*Created on 2005-7-15*/ o$J6 ~dn
package com.adt.service.impl; RUXCq`)"<
3LK%1+)4
import java.util.List; N6/T#UVns
8jnz}aBd
import net.sf.hibernate.HibernateException; !1:@8q
w]!0<
import org.flyware.util.page.Page; %}qbkkZ
import org.flyware.util.page.PageUtil; 8l)
j6>tH"i
import com.adt.bo.Result; %_f;G+fK\p
import com.adt.dao.UserDAO; .9M.|
import com.adt.exception.ObjectNotFoundException; `E>vG-9
import com.adt.service.UserManager; Ijo(^v@
Yp5L+~J[
/** =3'(A14C=
* @author Joa kX;$}7n
*/ uP|FJLY
publicclass UserManagerImpl implements UserManager { SkP[|g'56
j%tEZ"H
private UserDAO userDAO; JF9Hfs/jS
e!0OW7kV
/** r6Nm!Bq7
* @param userDAO The userDAO to set. 2$0)?ZC?=
*/ []}N
publicvoid setUserDAO(UserDAO userDAO){ P_Uutn~
this.userDAO = userDAO; nX[;^v/
} JP=ZUu
J!p<oW)a!
/* (non-Javadoc) x ^vt; $
* @see com.adt.service.UserManager#listUser u{C)qb5Pu
uHvaZMu
(org.flyware.util.page.Page) bZ5n,KQA5
*/ MCy~@)-IN
public Result listUser(Page page)throws #A<"4#}
S+T|a:]\7
HibernateException, ObjectNotFoundException { X"/~4\tJ"
int totalRecords = userDAO.getUserCount(); @ss):FwA
if(totalRecords == 0) +R\~3uj[7
throw new ObjectNotFoundException |63Y
>U"
Bc
^4 T1
("userNotExist"); z`#_F}v,m/
page = PageUtil.createPage(page, totalRecords); 5~}!@yzc
List users = userDAO.getUserByPage(page); nNR:cGfG
returnnew Result(page, users); 3M
N
} 8hB.fau
80&D""
} " $)yB
lB:l)!]||=
Y5%;p33uFG
}$aNOf%:
;`j U_
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 vm}G[
8S>>7z!U
询,接下来编写UserDAO的代码: {D(,ft;s^
3. UserDAO 和 UserDAOImpl: -!R
l(if
java代码: n;OHH{E{
GOr}/y;
vttrKVA
/*Created on 2005-7-15*/ _rjBc;a
package com.adt.dao; %b<%w
Zi1YZxF`Y
import java.util.List; !5.v'K'
;=p;v .l
import org.flyware.util.page.Page; WZ*&@|w
t)(v4^T
import net.sf.hibernate.HibernateException; JQT4N[rEE
}x0Z(
`
/** sU%"azc
* @author Joa RV92qn
B
*/ wE2x:Ge:
publicinterface UserDAO extends BaseDAO { #W5Yw>$
-\,VGudM}
publicList getUserByName(String name)throws gKQ@!UU8
+]L) >$6
HibernateException; Pd],}/ZG-
P>W8V+l![
publicint getUserCount()throws HibernateException; i'HST|!j
hht+bpHl
publicList getUserByPage(Page page)throws X[{\3Av
h/=-tr
HibernateException; Xz* tbW#
c Vg$dt
} =,E'~P
a71}y;W
Y3M','H([
K~JC\a\0
OR~G Ov|
java代码: C$y fMK,,N
G5+]DogS
7b,AQ9
/*Created on 2005-7-15*/ ?>TbTfmR
package com.adt.dao.impl; Gx|Dql
SyB-iQn
import java.util.List; ._(z~3s
UP*yeT,P,
import org.flyware.util.page.Page; u[J7Y
Y-7.Vjt^
import net.sf.hibernate.HibernateException; x`3.Wu\
import net.sf.hibernate.Query; R\
e#$"a5
4ioNA/E
import com.adt.dao.UserDAO; T~|PU{
;]u1~
/** w6v1 q:20
* @author Joa U\;Ml
*/ yh$ ~*UV
public class UserDAOImpl extends BaseDAOHibernateImpl ?a8nz, zb
|nfH-JytV
implements UserDAO { Bf(Mot^
04[)qPPS
/* (non-Javadoc) !$XO
U'n
* @see com.adt.dao.UserDAO#getUserByName G`WzJS*}v
#nDL
(java.lang.String) 5Wl,J _<F
*/ (ai72#nFtb
publicList getUserByName(String name)throws KK .cDAR
s9kTuhoK
HibernateException { wEv*1y4
String querySentence = "FROM user in class "mG!L$
z22N7W=7
com.adt.po.User WHERE user.name=:name"; P^n{Y~P=Q
Query query = getSession().createQuery ~Gwas0eNa
rcW#6VZ=
(querySentence); .Btv}b
query.setParameter("name", name); BiI{8`M!$x
return query.list(); GMyoSe%1/
} {AtfK>D
su%Z{f)#
/* (non-Javadoc) B=^2g}mgK
* @see com.adt.dao.UserDAO#getUserCount() Z#[>N,P
*/ v@]6<e$
publicint getUserCount()throws HibernateException { uvNnW}G4
int count = 0; {<~s&EPd
String querySentence = "SELECT count(*) FROM W *|OOa'
Je@p5(f
user in class com.adt.po.User"; BD?F`%-x
Query query = getSession().createQuery J$<:/^t
,at-ci\'
(querySentence); <"{+
count = ((Integer)query.iterate().next 5auL<Pq
}]Qmt5'NI
()).intValue(); }%
FDm@+
return count; bmSpbX\
} <w%Yq?^
sCL/pb]
/* (non-Javadoc) FC~|&
* @see com.adt.dao.UserDAO#getUserByPage =/M$
<+
U8Cw7u2
(org.flyware.util.page.Page) Py}!C@e
*/ t>m8iS>
publicList getUserByPage(Page page)throws /{49I,
{8ld:ZP
HibernateException { IZzhJK M1V
String querySentence = "FROM user in class ]5aux
>.n
Z&BM%.NZJ
com.adt.po.User"; 44g`=o@
Query query = getSession().createQuery ^?81.b|qb
\E>%W
(querySentence); Fwg#d[:u
query.setFirstResult(page.getBeginIndex()) mw2rSU I{
.setMaxResults(page.getEveryPage()); =kyJaT^5[
return query.list(); O[3q9*(
} a-SB1-5jf
2M!+gk=+
} I67k M{V
zDKLo 3:
0W!VV=j<}
VGkW3Nt0
Xd90n>4S
至此,一个完整的分页程序完成。前台的只需要调用 l;"ub^AH
7r:nMPX
userManager.listUser(page)即可得到一个Page对象和结果集对象 6C@0[Q\ER
}UJdE#4
的综合体,而传入的参数page对象则可以由前台传入,如果用 }7f 1(#{7
S"I#>^
webwork,甚至可以直接在配置文件中指定。 H@ 1[SKBl
kG_&-b
下面给出一个webwork调用示例: e2,<,~_K6
java代码: \emT:Frb
?Xy w<fMQ
oxxE'cx{g
/*Created on 2005-6-17*/ :*^(OnIe
package com.adt.action.user; i2`.#YJ&v
)dUd `g
import java.util.List; ;+aDjO2(
PprQq_j
import org.apache.commons.logging.Log; /zDSlj<c
import org.apache.commons.logging.LogFactory; YA1{-7'Q
import org.flyware.util.page.Page; ]JhDRJ\
q[Sp|C6x
import com.adt.bo.Result; Q{(,/}kA-
import com.adt.service.UserService; '_Hb}'sFI
import com.opensymphony.xwork.Action;
b{9HooQ{
$j$\ccG
/** !>"INmz
* @author Joa f@,hO5h(_|
*/ >TH-Q[
publicclass ListUser implementsAction{ OsHkAI
PW~cqo B71
privatestaticfinal Log logger = LogFactory.getLog .q~,.yI&j
#b<lt'gC
(ListUser.class); T-<> )N5y
uv_P{%TK
private UserService userService; s%0[DO3NV
g,{Ei]$>I
private Page page; ={wjeRp
O(:u( U7e
privateList users; U)T/.L{0i
JXRmu~W~l
/* :IOn`mRYu
* (non-Javadoc) x1 R!
* :&\E\9
* @see com.opensymphony.xwork.Action#execute() tCF0Ah
*/ T`(;;%
publicString execute()throwsException{ B 7x"ef
Result result = userService.listUser(page); eO"\UDBV
page = result.getPage(); } SWA|x
users = result.getContent(); ZJ{+_ax0K
return SUCCESS; cfO^CC
} )f_"`FH0d
k[^}ld[
/** fmT3Afl5c
* @return Returns the page. "O"^\f
*/ d-K5nRyI
public Page getPage(){ h P6fTZ=Ln
return page; Yg:74; .
} }f0^9(
oM?
C62g\
/** ` wsMybe#
* @return Returns the users. _4x[}e7KF
*/ nd*!`P
publicList getUsers(){ c] :J/'vc
return users; O#89M%
} VN55!l'OV
rg]A_(3Bb
/** II f >z_m
* @param page ]#Z$jq{,
* The page to set. Q& unA3
*/ bvxxE/?Ni
publicvoid setPage(Page page){ _sD]Viqc
this.page = page; mc[_>[m
} Y-q,Ovf!
!WVabdt
/** MHzsxF|
* @param users c# 4ZDjvm6
* The users to set. w7]p9B
*/ "e!$=;5
publicvoid setUsers(List users){ ~wd?-$;070
this.users = users; @"#gO:|[i0
} Wb-'E%K
,"lBS?
/** 1:~m)"?I_^
* @param userService p<^/T,&I
* The userService to set. f<t*#]<