Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {pz7ADK<
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 cxpG6c
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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 -h%1rw
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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 l9vJ]
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分页支持类: 6oy[0hj
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java代码: Wo7`gf_ (
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package com.javaeye.common.util; <8YIQA
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import java.util.List; [Y-3C47
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publicclass PaginationSupport { 1BOv|xPjZ
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publicfinalstaticint PAGESIZE = 30; FJ{6_=@D
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privateint pageSize = PAGESIZE; {+jO/ZQu5
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privateList items; }.N~jx0R
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privateint totalCount; sOhKMz
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privateint[] indexes = newint[0]; Q9{f'B
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privateint startIndex = 0; NKMVp/66D
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public PaginationSupport(List items, int r;@"s g
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totalCount){ 2U&+K2
setPageSize(PAGESIZE); K:b^@>XH
setTotalCount(totalCount); #+(@i|!ifo
setItems(items); N ,nvAM
setStartIndex(0); UY^TTRrH
} \:9<d@?
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public PaginationSupport(List items, int k%?qN,Cl
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totalCount, int startIndex){ rAh|r}R
setPageSize(PAGESIZE); ,*Wp$
setTotalCount(totalCount); 7}puj%JS
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setItems(items); tu6<>
setStartIndex(startIndex); <6.?:Jj
} 9v?rNJs
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public PaginationSupport(List items, int TF~cDn
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totalCount, int pageSize, int startIndex){ qflOi8
setPageSize(pageSize); <{IeCir
setTotalCount(totalCount); TFDzTD
setItems(items); jKb4d9aX
setStartIndex(startIndex); N14Q4v-*x
} FB2{qG3
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publicList getItems(){ ZwMd 22
return items; =}'7}0M_=
} 2?kVbF
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publicvoid setItems(List items){ Zx^R -9
this.items = items; cp2a @
} *0x!C8*`Xe
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publicint getPageSize(){ e,
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return pageSize; d#|%h]
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} G6p R?K+
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publicvoid setPageSize(int pageSize){ +do*C=z
this.pageSize = pageSize; RmJ|g<
} z[l_<`J$9
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publicint getTotalCount(){ `$XgfMBf |
return totalCount; {m/KD 'b_
} ce7$#
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publicvoid setTotalCount(int totalCount){ 8@r>`c
if(totalCount > 0){ >%A~ :
this.totalCount = totalCount; y(X^wC
int count = totalCount / S^{tRPF%d
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pageSize; A`1-c
if(totalCount % pageSize > 0) &'u%|A@
count++; _7<G6q2(
indexes = newint[count]; {EJ+
for(int i = 0; i < count; i++){ FTu<$`!1L
indexes = pageSize * +>Pq]{Uf1j
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i; 'j;i4ie>*x
} ?dmwz4k0
}else{ n^` `)"
this.totalCount = 0; Y8for'
} ,qj M1xkL$
} )kIjZ
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publicint[] getIndexes(){ !eP0b~$/^J
return indexes; vdd>\r)v
} ik5"9b-\<
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publicvoid setIndexes(int[] indexes){ et<@3wyd]
this.indexes = indexes; ]F #0to
} d?><+!a
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publicint getStartIndex(){ ~?B\+6<V
return startIndex; e}ivvs2
} $]MOAj"LH
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publicvoid setStartIndex(int startIndex){ cFHSMRB|P
if(totalCount <= 0) :3D[~-/S
this.startIndex = 0; cd] X5)$h
elseif(startIndex >= totalCount) V o%GO9b;
this.startIndex = indexes = Q"(9[Az
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[indexes.length - 1]; j.:f=`xf
elseif(startIndex < 0) P_(<?0l
this.startIndex = 0; {6iHUK
else{
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this.startIndex = indexes |;R-q8
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[startIndex / pageSize]; m Gx{Vpt
} 4MRN{W6
} mxICQ>s
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publicint getNextIndex(){ A:*$r Hbzl
int nextIndex = getStartIndex() + k[\JT[Mp
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pageSize; !X 0 (4^
if(nextIndex >= totalCount) zKGr(9I
return getStartIndex(); |sB L(9
else -v=tM6
return nextIndex; ZVz*1]}
} *}Rd%'
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publicint getPreviousIndex(){ -l{ wB"
int previousIndex = getStartIndex() - h([qq<Lzs
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pageSize; XlJ+:st
if(previousIndex < 0) 5D>cbzP@
return0; ~e=KBYDBu
else S9 @*g3
return previousIndex; gXB&Sgjo
} Y{L|ja%9?
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} iBCIJ!;
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抽象业务类 2>im'x 5
java代码: MJ.Kor
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/** kS_37-;
* Created on 2005-7-12 3Z74&a$
*/ X
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package com.javaeye.common.business; ar@ysBy
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import java.io.Serializable; uR82},r$m
import java.util.List; BA_l*h%=Cc
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import org.hibernate.Criteria; BF
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import org.hibernate.HibernateException; >2tosxH M
import org.hibernate.Session; Rr>""
import org.hibernate.criterion.DetachedCriteria; _? u} Jy_
import org.hibernate.criterion.Projections; N}q*(r!q<
import r8!M8Sc
/P*ph0S-
org.springframework.orm.hibernate3.HibernateCallback; #M92=IH
import qb5IpI{U
#e6x_o|
org.springframework.orm.hibernate3.support.HibernateDaoS > u=nGeO
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upport; #DcK{|ty
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import com.javaeye.common.util.PaginationSupport; yJw4!A 1!
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public abstract class AbstractManager extends DkBVk+
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HibernateDaoSupport { IE&G7\>(yO
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privateboolean cacheQueries = false; < !]7Gt
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privateString queryCacheRegion; BF]+fs`
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publicvoid setCacheQueries(boolean G_?qY#"(
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cacheQueries){ zuvP\Y=V`
this.cacheQueries = cacheQueries; jce2lXMm
} n/IDq$/P
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publicvoid setQueryCacheRegion(String Zy >W2(<
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queryCacheRegion){ RQ[6svfP
this.queryCacheRegion = e6^iakSd.L
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queryCacheRegion; kk3G~o+
} S;S_<GX
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publicvoid save(finalObject entity){ [E/8E
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getHibernateTemplate().save(entity); z#sSLE.$Z
} P4~C0z
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publicvoid persist(finalObject entity){ mKBPIQ+ZS
getHibernateTemplate().save(entity); ;EfREfk
} 3(La)|k
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publicvoid update(finalObject entity){ p\M\mK
getHibernateTemplate().update(entity); c (0Ez@
} PWs=0.Wj
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publicvoid delete(finalObject entity){ uJ/&!q<3
getHibernateTemplate().delete(entity); 5K?%Eo72!=
} +)TOcxF%
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publicObject load(finalClass entity, Le}-F{~`^
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finalSerializable id){ O.+X,CQG*
return getHibernateTemplate().load +jX.::UPm
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(entity, id); 1fb!sbGD.k
} `oo(\O7t=
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publicObject get(finalClass entity, C@s;0-qL
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finalSerializable id){ -AU!c^-o
return getHibernateTemplate().get n7K\\|X
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(entity, id); *|k/l I
} i fbO<
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publicList findAll(finalClass entity){ qW:\6aEG
return getHibernateTemplate().find("from &sJ%ur+G
/|{~GD +A&
" + entity.getName()); 9`sIE _%+
} .(2ui~ed
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publicList findByNamedQuery(finalString !RwOUCk
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namedQuery){ (.B+U'6
return getHibernateTemplate ?]u=5gqUU
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().findByNamedQuery(namedQuery); 0CRk&_ht
} ~b.e9FhdA
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publicList findByNamedQuery(finalString query, Nb@zn0A(;
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finalObject parameter){ >R}p*=J
return getHibernateTemplate 9q!./)
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().findByNamedQuery(query, parameter); ]QAMCu(>
} 9 ~$'?
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publicList findByNamedQuery(finalString query, )s4a<Sc]
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finalObject[] parameters){ knJoVo]
return getHibernateTemplate Ro|%pT
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().findByNamedQuery(query, parameters); ,,[pc
} :IlJQ{=W
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publicList find(finalString query){ ^J Y]w^u
return getHibernateTemplate().find w(Hio-l=
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(query); F[5\
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} gT~Yn~~b
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publicList find(finalString query, finalObject /DBldL7yi
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parameter){
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return getHibernateTemplate().find G;3N"az
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(query, parameter); *
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} oaJnLd90W
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public PaginationSupport findPageByCriteria ESAFsJ$r;
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria Xm!;
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); i5 F9*
} Lk~aMbw#
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public PaginationSupport findPageByCriteria J<'I.KZ\z
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(final DetachedCriteria detachedCriteria, finalint eDPmUlC+-
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startIndex){ +kK6G#c
return findPageByCriteria 5<y pK`Kq
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(detachedCriteria, PaginationSupport.PAGESIZE, ^|1)6P}6
evBr{oi@
startIndex); 5E!G
} oj1,DU
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public PaginationSupport findPageByCriteria ]TmxCTVL
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(final DetachedCriteria detachedCriteria, finalint z3:tSjF
e):rr*
pageSize, (\M&Q-xZ
finalint startIndex){ CgO&z<A!&
return(PaginationSupport) M'4$z^@Z
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getHibernateTemplate().execute(new HibernateCallback(){ 9cm9;
publicObject doInHibernate D8''q%
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(Session session)throws HibernateException { M@/Hd0$
Criteria criteria = ^
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detachedCriteria.getExecutableCriteria(session); S!;:7?mq
int totalCount = BL^8gtdn
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((Integer) criteria.setProjection(Projections.rowCount |Vs?yW
<8Zm}-U
()).uniqueResult()).intValue(); nrpxZA
criteria.setProjection \tWFz(
|#. J
(null); D!oELZ3
List items = +w ]KK6
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criteria.setFirstResult(startIndex).setMaxResults J!GWP:b3
1/H9(2{L
(pageSize).list(); i;XkH4E:)
PaginationSupport ps = yfd$T}WW6
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new PaginationSupport(items, totalCount, pageSize, nd[{DF?)/
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startIndex); wA#w]8SM
return ps; 1[;~>t@C
} s@ ~Y!A
}, true); '!%Zf;Fjr
} XOe8(cXa9
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public List findAllByCriteria(final fQ,L~:Y =
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DetachedCriteria detachedCriteria){ : 6*FnKD
return(List) getHibernateTemplate *)jhhw=34
M;{btu^a
().execute(new HibernateCallback(){ c9eLNVM
publicObject doInHibernate kq
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(Session session)throws HibernateException { zNs8yMnFr
Criteria criteria = sr&hQ
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detachedCriteria.getExecutableCriteria(session); DhAQ|SdCf
return criteria.list(); K; +w'/{
} tX$v)O|
}, true); |Ts|>"F'
} Jmp%%^
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public int getCountByCriteria(final jx3J$5
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DetachedCriteria detachedCriteria){ =wEqI)Td
Integer count = (Integer)
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getHibernateTemplate().execute(new HibernateCallback(){ Y|NANjEAfm
publicObject doInHibernate J\BTrN 7
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(Session session)throws HibernateException { #]iSh(|8
Criteria criteria = 6 Ch
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DO #!ce
detachedCriteria.getExecutableCriteria(session); f+/AD
return |Mj2lZS
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criteria.setProjection(Projections.rowCount FG^Jh5
ld-Cb3R^
()).uniqueResult(); c?;YufH'j
} !5hNG('f
}, true); }J~
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return count.intValue(); R<J1bH1n3
} Eu4-=2!4
} 3q!hY
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用户在web层构造查询条件detachedCriteria,和可选的 6z6\-45
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <Be:fnPX7
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PaginationSupport的实例ps。 )<?^~"h
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ps.getItems()得到已分页好的结果集 V!Px975P
ps.getIndexes()得到分页索引的数组 -A?6)ggf.
ps.getTotalCount()得到总结果数 xp!MA
ps.getStartIndex()当前分页索引 56;^
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ps.getNextIndex()下一页索引 :6
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ps.getPreviousIndex()上一页索引 Z?Cl5o&lb
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 AG3iKk??T
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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 [9wuaw"~[Z
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一下代码重构了。 S2TyNZbQ
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我把原本我的做法也提供出来供大家讨论吧: <sALA~p|0
7Rba@ cs9
首先,为了实现分页查询,我封装了一个Page类: Xjy5Yj
java代码: U?bQBHIC
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/*Created on 2005-4-14*/ >FVBn;1
package org.flyware.util.page; eucacXiZ
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/** >1}RiOd3
* @author Joa #2/2Xv
* 88@" +2
*/ |ODi[~y
publicclass Page { FZvh]ZX
-`I&hzl6E
/** imply if the page has previous page */ B<p-qPR K
privateboolean hasPrePage; b"DV8fdX
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/** imply if the page has next page */ .T2P%Jn.
privateboolean hasNextPage; pR3@loFQ`o
CFLWo1
/** the number of every page */ UJ/=RBfkJ
privateint everyPage; wWVLwp4-
%nRz~3X|+v
/** the total page number */ 9JDdOjqo
privateint totalPage; ]4uY<9VL
F*}.0SQ
/** the number of current page */ w$aiVOjgT
privateint currentPage; X6T*?t3!9[
\>DMN #
/** the begin index of the records by the current R{3?`x!fY
bAUruTn
query */ n$*e(
privateint beginIndex; L@|xpq
#OQT@uF!
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/** The default constructor */ j3Sz+kOf,
public Page(){ Z[,A>tJ
kBRy(?Mft&
} j>}<FW-N
6h5,XcO4
/** construct the page by everyPage 6>X9|w
* @param everyPage 5DI&pR1eZ
* */ <>Nq]WqA
public Page(int everyPage){ ?oD]J
this.everyPage = everyPage; mRECdGst
} 6EX_IDb
;8~tt I
/** The whole constructor */ <Z>p1S
public Page(boolean hasPrePage, boolean hasNextPage, nNEIwlj;
J7RO*.O&Iq
'm4v)w<y#
int everyPage, int totalPage, JZUf-0q
int currentPage, int beginIndex){ !4/s|b9K
this.hasPrePage = hasPrePage; f\|R<3 L
this.hasNextPage = hasNextPage; \FL`b{!+ N
this.everyPage = everyPage; f4[Bj{F
this.totalPage = totalPage; 4Odf6v,*@
this.currentPage = currentPage; k"L?("~
this.beginIndex = beginIndex; EOn[!
} #~I.F4
OgOs9=cE{
/** k-;A9!^h
* @return f]*TIYicc
* Returns the beginIndex. eyIbjgpV
*/ KE_GC ;bQ
publicint getBeginIndex(){ -Wt(t2
return beginIndex; ju8DmC5
}
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9i?Q=Vuc~<
/** U9/>}Ni%3G
* @param beginIndex H wu(}
* The beginIndex to set. .szc-r{
*/ /7o{%~O
publicvoid setBeginIndex(int beginIndex){ 9R1S20O
this.beginIndex = beginIndex; u&npUw^Va
} p(8[n^~,i
"%?$BoJR0
/** S_|VlI
* @return g{U?Y"
* Returns the currentPage. 1M<;}hJ{/
*/ ;+Mee^E>!
publicint getCurrentPage(){ %
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return currentPage; X%lk] &2
} HC$rC"f
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/** q
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* @param currentPage Q$B\)9`v[
* The currentPage to set. ? JliKFD%
*/ AnD#k]
publicvoid setCurrentPage(int currentPage){ #
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this.currentPage = currentPage; C"[d bh!
} ]T<\d-!CZN
t91z<Y|
/** 5_yu4{@;y
* @return upc-Qvk
* Returns the everyPage. b&_u+g
*/ -nL!#R{e
publicint getEveryPage(){ Dx*tolF
return everyPage; !=B=1th4
} S4!}7NOh
tT`{xM
/** D3.$Vl,.
* @param everyPage G1?m}{D)
* The everyPage to set. Mf_urbp]
*/ *vS)aRK
publicvoid setEveryPage(int everyPage){ 1(4}rB3
this.everyPage = everyPage; :vWixgLg
} 6qYK"^+xu
QZ?%xN(4
/** L_(Y[!
* @return /@xL {
* Returns the hasNextPage. .{t]Mc
*/ '1NZSiv+C?
publicboolean getHasNextPage(){ hha!uD~(
return hasNextPage; dZ;rn!dg>
} s^lm
81;
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/** C%T$l8$
* @param hasNextPage CeD(!1VG
* The hasNextPage to set. v;$cx*?
*/ ;>jLRx<KC
publicvoid setHasNextPage(boolean hasNextPage){ F*{1, gb
this.hasNextPage = hasNextPage; mO0a: i!
} %;-r->
L`@)*x)~R
/** 71wtO
* @return yGZsPQIaV
* Returns the hasPrePage. /~6)Vt
*/ dkI(&/
publicboolean getHasPrePage(){ d:GAa
return hasPrePage; JM> 4m)h#
} >DkRl
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/** !`qw"i
* @param hasPrePage (|t)MnPfY
* The hasPrePage to set. <HMmsw
*/
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publicvoid setHasPrePage(boolean hasPrePage){ ,Z aPY
this.hasPrePage = hasPrePage; ki<4G
} }:9UI
%YV3-W8S0
/** m14OPZ<3?-
* @return Returns the totalPage. %5-
* A"pV 7
y
*/ daN#6e4Z+;
publicint getTotalPage(){ ?<h|Q~JH
return totalPage; whb,2=gIE
} ^ygh[.e,
p5?8E$VHV
/** =qy{8MsjA
* @param totalPage s3+6Z~g'B
* The totalPage to set. =! P
*/ fF.qQTy;7
publicvoid setTotalPage(int totalPage){ oaMh5FPy
this.totalPage = totalPage; D4;6}gRC
} l>{+X )
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} OJTEvb6nPg
q%\rj?U_
,`.`}'
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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 .In8!hjYy4
03^?+[C
个PageUtil,负责对Page对象进行构造: e}bY9
java代码: r>.^4Z@
kp>AZVk
8iKupaaOX
/*Created on 2005-4-14*/ 4M3{P
package org.flyware.util.page; S1G=hgF_L
f3M~2jbv'p
import org.apache.commons.logging.Log; kf>L
import org.apache.commons.logging.LogFactory; 6S6E
1~
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/** &Rxy]kBA
* @author Joa lgei<\6~n5
* g4CdzN~
*/ xjO((JC
publicclass PageUtil { s\dhQZ w3
$bo 5:c
privatestaticfinal Log logger = LogFactory.getLog +:m'a5Dm
m~U2L
(PageUtil.class); eHQ3K#M#
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/** & GM&,
* Use the origin page to create a new page vddh 2G
* @param page 8j%hxAV$
* @param totalRecords "F8A:tR
* @return 8"2X 8C8
*/ .pd_SQ~
publicstatic Page createPage(Page page, int 9_5tA'Q
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totalRecords){ 50J"cGs~
return createPage(page.getEveryPage(), Q?"-[6[v
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page.getCurrentPage(), totalRecords); 53jtwklA
} o;<oXv
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/** wD'LX
* the basic page utils not including exception SYZS@o
b*@y/ e\u`
handler ?iQA>P9B
* @param everyPage f7Fr%*cO
* @param currentPage 4RU/y+[o
* @param totalRecords q9mYhT/Im
* @return page p/GYfa
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*/ AroXf#.
publicstatic Page createPage(int everyPage, int xs ^$fn\
<+2M,fq+
currentPage, int totalRecords){ "Ca?liy
everyPage = getEveryPage(everyPage); 2 -
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currentPage = getCurrentPage(currentPage); *q/oS8vavd
int beginIndex = getBeginIndex(everyPage, 5Zdxn>
h=Xr J
currentPage); 7<?~A6
int totalPage = getTotalPage(everyPage, tzFgPeo$;
b6E,u*)"
totalRecords); )$ +5imi
boolean hasNextPage = hasNextPage(currentPage, <^,5z!z}
I];Hx'/<~
totalPage); -A A='s
boolean hasPrePage = hasPrePage(currentPage); Axtf,x+lH
,0=@cJ
returnnew Page(hasPrePage, hasNextPage, 3"OD"
everyPage, totalPage, B U^3U x$
currentPage, ,'69RL?-Wg
!b+/zXp3I
beginIndex); L8zY?v(bG
} ?MhY;z`=
&v#*
privatestaticint getEveryPage(int everyPage){ #[a+m
return everyPage == 0 ? 10 : everyPage; 8`/nk`;
} (!^(74
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privatestaticint getCurrentPage(int currentPage){ G()- NJ{
return currentPage == 0 ? 1 : currentPage; i C
nWb
} k 8Swra?j
/o19/Pvwm
privatestaticint getBeginIndex(int everyPage, int kN)m"}gX
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currentPage){ LOkNDmj
return(currentPage - 1) * everyPage; 9V%s1@K
} Ba],ONM4k
*CH lg1
privatestaticint getTotalPage(int everyPage, int <Eo;CaaF/
e Ert_@}
totalRecords){ ,\FJVS;NeJ
int totalPage = 0; Y M_\ ZK:
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if(totalRecords % everyPage == 0)
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totalPage = totalRecords / everyPage; wER>a (
else '14
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totalPage = totalRecords / everyPage + 1 ; 54 Baz
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return totalPage; 45hjN6
} cIO7RD$8
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privatestaticboolean hasPrePage(int currentPage){
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return currentPage == 1 ? false : true; s9wcZO
} C
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privatestaticboolean hasNextPage(int currentPage, ^]$x/1I;
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int totalPage){ y6lle<SIu
return currentPage == totalPage || totalPage == \I@=EF- &
5Z 7 <X2
0 ? false : true; N%A[}Y0;MW
} \V|\u= @H
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} D! 1oYr
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aMSX"N"ot
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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。 ag-\(i;K]
m"~^-mJ-
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 9ZL3p!
@LS*WJ< w-
做法如下: );wSay>%(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ^1vh5D
1@)8E`u
的信息,和一个结果集List: M%dXy^e
java代码: JRkC~fv
b<de)MG
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/*Created on 2005-6-13*/ BpL,<r,
package com.adt.bo; t%e}'?#^
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import java.util.List; z O
8I)66
import org.flyware.util.page.Page; c|lo%[]R!
;/fZh:V2
/** GNzkVy:u
* @author Joa yVvO!
*/ [a;U'v*
publicclass Result { J~6+zBF
Vf#X[$pc/
private Page page; W>Eee?
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private List content; [V ~(7U
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/** hHsCr@i
* The default constructor 0*MY4r|-
*/ V]cD^Fqp
public Result(){ {(@M0?
super(); X !g"D6'
} 1D03Nbh|5
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/** H 3YFbR
* The constructor using fields .eAN`-t;
* |1zoT|}q
* @param page `Ym7XF&
* @param content sr+*
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*/ Q#
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public Result(Page page, List content){ _-$"F>
this.page = page; lCBb0k2
this.content = content; ?(el6 J}
} %|$h<~
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/** GndU}[0J
* @return Returns the content. pe>R2<!$
*/ $<.\,wW*'w
publicList getContent(){ *2ZX*w37
return content; w yP|#Z\
} 5F{NPKaQ
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/** QS:dr."k
* @return Returns the page. eAh~`
*/ `LU[+F8<
public Page getPage(){ :DTKZ9>2D
return page; 095:"GvO
}
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h?
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/** )?#*GMWU
* @param content U}ei2q\
* The content to set. F.2<G.9
*/ G.Z:00x
public void setContent(List content){ _ KBN
this.content = content; j^#4!Ue
} @: u>
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/** P,-f]k[_
* @param page FES_:?.0
* The page to set. v#1}(
hb
*/ h+)XLs
publicvoid setPage(Page page){ TbqH-R3W
this.page = page; o$]wd*+
} (_h<<`@B
}
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2. 编写业务逻辑接口,并实现它(UserManager, @X@?jj&
84v7g`lrR
UserManagerImpl) .{[+d3+,
java代码: c++GnQc.
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/*Created on 2005-7-15*/ *->2$uWP
package com.adt.service; E9e|+$
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import net.sf.hibernate.HibernateException; `|maf=SnY5
{;uOc{~+
import org.flyware.util.page.Page; ~9%L)nC2'
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import com.adt.bo.Result; DX>Yf}
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/** 0c6b_%Rd
* @author Joa KE>|,Ur
*/ v_M-:e3`
publicinterface UserManager { WzD=Ol
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public Result listUser(Page page)throws Vwxb6,}Z
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HibernateException; bMe/jQuL.$
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} zh8\
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je_:hDr
= BcKWC
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java代码: jSi\/(E
W:5uoO]=<
UnTnc6Bo7W
/*Created on 2005-7-15*/ @ sLb=vb
package com.adt.service.impl; {}gx;v)
BwpEIV@b]
import java.util.List;
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d$DNiJ ,
import net.sf.hibernate.HibernateException; lICpfcc(+
`"@Pr,L
import org.flyware.util.page.Page; @8\7H'K"\
import org.flyware.util.page.PageUtil; X#v6v)c
}eKY%WU>O
import com.adt.bo.Result; i2bkgyzB.
import com.adt.dao.UserDAO; Xy(8}
import com.adt.exception.ObjectNotFoundException; ?2d! ^!9
import com.adt.service.UserManager; Z`jc*jgy
SZ$~zT;c
/** ENoGV;WG
* @author Joa V46=48K.
*/ =:neGqd\_E
publicclass UserManagerImpl implements UserManager { >)`yG'[
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private UserDAO userDAO; 6gr?#D -F
b*5Yy/U
/** {>EM=ZZfg
* @param userDAO The userDAO to set. dZ6\2ok+
*/ +K2p2Dw(k
publicvoid setUserDAO(UserDAO userDAO){ }N^3P0XjYq
this.userDAO = userDAO; "W71#n+[
} _;zIH5 H
Z [[AmxE'l
/* (non-Javadoc) mFk6a{+YX
* @see com.adt.service.UserManager#listUser "UM*(&
YRU1^=v
(org.flyware.util.page.Page) %"yy8~|
*/ :t)<$dtf[
public Result listUser(Page page)throws ]h3{MTr/
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HibernateException, ObjectNotFoundException { xZ=6
int totalRecords = userDAO.getUserCount(); 0,{tBo
if(totalRecords == 0) [B_(,/?
throw new ObjectNotFoundException &$H7vdWNy
RyuI2jEy
("userNotExist"); 7Be\^%
page = PageUtil.createPage(page, totalRecords); I_.Jo `lK~
List users = userDAO.getUserByPage(page); qI=j>x
returnnew Result(page, users); =|j~*6Hd
} ta
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} w *Txc}
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o],z/MPL
XYrZI/R
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 |'+ [ '
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询,接下来编写UserDAO的代码: 1EmZ/@k/Y
3. UserDAO 和 UserDAOImpl: [TaYNc!\
java代码: o[Gp *o\
!
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_~}n(?>
/*Created on 2005-7-15*/ <&CzM"\Em
package com.adt.dao; &sA@!
Y^(NzN
import java.util.List; Kk9eJ\
#cCR\$-~
import org.flyware.util.page.Page; <jz\U7TBf
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import net.sf.hibernate.HibernateException; b0:5i<"w6
{G i:W/jJ
/** E|9'{3$
* @author Joa - ]Mbe2;
*/ H_&z-g`
publicinterface UserDAO extends BaseDAO { JI7.:k;
A<*G;
publicList getUserByName(String name)throws 6
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HibernateException; Jc9BZ`~i
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publicint getUserCount()throws HibernateException; ?ISv|QpC
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publicList getUserByPage(Page page)throws X"fSM
#
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HibernateException; fa#5pys
U#gv ~)\k
} D//uwom
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r>kDRIHB
Kc#42C;t/
java代码: IzWS6!zKU
oc0z1u
mA" 82"
/*Created on 2005-7-15*/ JANP_b:t
package com.adt.dao.impl; Xxmvg.Nl
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import java.util.List; ^(.utO
k<.VR"I
p
import org.flyware.util.page.Page; @'lO~i
no
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import net.sf.hibernate.HibernateException; 8 aC]" C
import net.sf.hibernate.Query; R2B0?fu
ptCAtEO72
import com.adt.dao.UserDAO; ;Y@"!\t}
wPRs.(]_
/** Zt{\<5j
* @author Joa )an,-EIX%
*/ !<AY0fpY
public class UserDAOImpl extends BaseDAOHibernateImpl g|
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implements UserDAO { EwuBL6kN
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/* (non-Javadoc) lKA2~ o
* @see com.adt.dao.UserDAO#getUserByName K4|{[YpPB
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(java.lang.String) ufc_m4PN
*/ &-B&s.,kj
publicList getUserByName(String name)throws <CM}g4Y
<cx,Z5W
HibernateException { .:?cU#.
String querySentence = "FROM user in class $/XR/
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com.adt.po.User WHERE user.name=:name"; ^[u*m%UB
Query query = getSession().createQuery B>{\qj)%
;=oGg%@aP
(querySentence); 3!<} -sW4
query.setParameter("name", name); oHj64fE9
return query.list(); h6Q-+_5
} eK_Yt~dj
p}{V%!`_
/* (non-Javadoc) !tr
/$
* @see com.adt.dao.UserDAO#getUserCount() .0H!B#9
*/ /`YbHYNF[
publicint getUserCount()throws HibernateException { 8C4=f
int count = 0; O,A}p:Pgs
String querySentence = "SELECT count(*) FROM 7J$5dFV2
wG2-,\:
user in class com.adt.po.User"; Q{))+'s2h
Query query = getSession().createQuery 'h~I#S4!
8~s-@3J
(querySentence); AcCM
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count = ((Integer)query.iterate().next `h+1u`FJ
nbM7 >tnsk
()).intValue(); .}||!
return count; RI2Or9.
} @Tl!A1y?
D |BP]j}6
/* (non-Javadoc) |0A:0'uA!
* @see com.adt.dao.UserDAO#getUserByPage #Ies
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9e xHR&>{
(org.flyware.util.page.Page) Q`4]\)Dp
*/ c-, 6k
publicList getUserByPage(Page page)throws KJLK]lf}d
nM,5KHU4a
HibernateException { [AHZOA
String querySentence = "FROM user in class i<%
I-`qo7dQ_S
com.adt.po.User"; W=)wiRQm
Query query = getSession().createQuery c(y~,hN&p
<78LB/:
(querySentence); fX 41o#
query.setFirstResult(page.getBeginIndex()) xFcRp2W9R
.setMaxResults(page.getEveryPage()); eS{ xma
return query.list(); 3ZKaqwK
} 9X2l H~C
^"?b!=n!
} }{(|^s =
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B hnwb0b<
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mlmXFEC
至此,一个完整的分页程序完成。前台的只需要调用 1 n86Mp1.e
$EuWQq7OI2
userManager.listUser(page)即可得到一个Page对象和结果集对象 {=K u9\
v8L&F9
o
的综合体,而传入的参数page对象则可以由前台传入,如果用 +v}R-gNR
V^^nJs
tV
webwork,甚至可以直接在配置文件中指定。 `Wf)qMb
Nu%JI6&R
下面给出一个webwork调用示例: |UO&18Y7-
java代码: 7:_\t!]
|NiWr1&i0
G?OwhX
/*Created on 2005-6-17*/ _Di}={1[.
package com.adt.action.user; {lhdropd
D|Tv`47ntu
import java.util.List; ;%R+]&J
`Y`QxU!d%
import org.apache.commons.logging.Log; pd rF/U+
import org.apache.commons.logging.LogFactory; L'J Ekji"
import org.flyware.util.page.Page; H#joc0?P
FSvtiNW<
import com.adt.bo.Result; I@f">&^
import com.adt.service.UserService; Y}C~&Ph