Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 2o2jDQ|7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 R8LJC]6Bh
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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 V>D8l @
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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 )#S;H$@$
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分页支持类: T_iX1blrgh
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java代码: <O:}dXqZ
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package com.javaeye.common.util; j.=&qYc0"
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import java.util.List; 0V;9v
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publicclass PaginationSupport { Ckd
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publicfinalstaticint PAGESIZE = 30; /LwS|c6}}
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privateint pageSize = PAGESIZE; `C pfQP&^
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privateList items; nA owFdCD
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privateint totalCount; <pA%|]
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privateint[] indexes = newint[0]; 2{U5*\FhVX
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privateint startIndex = 0; `qoRnG
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public PaginationSupport(List items, int ^mH:8_=(.
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totalCount){ l4Au{%j\
setPageSize(PAGESIZE); -S\gDB bb
setTotalCount(totalCount); HxUJ 0Q
setItems(items); ,9,cN-/a
setStartIndex(0); _2Zc?*4
} ,GeW_!Q[
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public PaginationSupport(List items, int :m]KVcF.
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totalCount, int startIndex){ Ms<v81z5T
setPageSize(PAGESIZE); J:Mn5hdK=
setTotalCount(totalCount); >c`r&W.t
setItems(items); h2jrO9
setStartIndex(startIndex); pyUzHF0
} Fs$mLa
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public PaginationSupport(List items, int g)dKXsy(F
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totalCount, int pageSize, int startIndex){ `.i #3P
setPageSize(pageSize); (N"9C+S}
setTotalCount(totalCount); @\U;?N~k
setItems(items); vzX%x ul
setStartIndex(startIndex); &s#O iF8
} |@W|nbAfX
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publicList getItems(){ :|\[a0ZL
return items; Cl6P,C
} q}PUwN6
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publicvoid setItems(List items){ 0g8ykGyx
this.items = items; C5,\DdCX,
} ,NAwSmocVP
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publicint getPageSize(){ Sq]VtQ(
return pageSize; 8q]_> X
} `\beQ(g
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publicvoid setPageSize(int pageSize){ t5CJG '!ql
this.pageSize = pageSize; $b U.6
} /&N\#;kK?b
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publicint getTotalCount(){ %)ri:Q q
return totalCount;
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} :]icW^%
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publicvoid setTotalCount(int totalCount){ 3mQ3mV:
if(totalCount > 0){ h e=A%s
this.totalCount = totalCount; [jz@d\k$_
int count = totalCount / &E]<KbVx
}0[<xo>K
pageSize; P^aNAa
if(totalCount % pageSize > 0) `*o ko[\3
count++; (fYYcpd,k
indexes = newint[count]; q*K[?
for(int i = 0; i < count; i++){ v}5||s!=
indexes = pageSize * U:AB%gr[
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i; eN'b"_D
} 6W<Ig;
}else{ j/8q
this.totalCount = 0; CZ!gu Y=
} !5qV}5
} w7E#mdW
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publicint[] getIndexes(){ ~OMo$qt`lP
return indexes; s"`Oj5
} (zPsA
},=ORIB B:
publicvoid setIndexes(int[] indexes){ ef@F!s_fI
this.indexes = indexes; 5g`J}@"k
} ta@fNS4
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publicint getStartIndex(){ 8Ow#W5_3|
return startIndex; [F!h&M0z
} q>s`G
} rX)A\ g6
publicvoid setStartIndex(int startIndex){ (&=3Y8
if(totalCount <= 0) >uo=0=9=
this.startIndex = 0; i# fvF)
elseif(startIndex >= totalCount) A 4*D3\>%u
this.startIndex = indexes :*vSC: q
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[indexes.length - 1]; [x%8l,O
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elseif(startIndex < 0) eNK6=D|
this.startIndex = 0; RA!8AS?
else{ 4av
this.startIndex = indexes ^jXKM!}-E
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[startIndex / pageSize]; iL<FFN~{
} J vl-=~
} }R~C<3u\2
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publicint getNextIndex(){ RT2&^9-
int nextIndex = getStartIndex() + dP<i/@21Wm
8PqlbLo1
pageSize; jgqeDl\=+
if(nextIndex >= totalCount) k~2FlRoC^
return getStartIndex(); tI
else 7H4\AG\>
return nextIndex; @nnX{$YX
} 9&HaEAme
E Uq6)
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publicint getPreviousIndex(){ >CqZ75>
int previousIndex = getStartIndex() - u`XZtF<vf
gk}.LE
pageSize; mqBX1D`e2
if(previousIndex < 0) 3*F|`js"
return0; K<k\A@rv8H
else ~iIFe+6
return previousIndex; K#N5S]2yb
} ZftucD|ZY/
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} Y3ypca&P9
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抽象业务类 MM~4D
java代码: %C)|fDwN
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/** <899r \
* Created on 2005-7-12 X;{U? `b-
*/ ;T<'GP'/r
package com.javaeye.common.business; }5d|y*
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import java.io.Serializable; EkOn Rm_hn
import java.util.List; m:g%5'qDZ
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import org.hibernate.Criteria; SIzA0
import org.hibernate.HibernateException; e63io0g>
import org.hibernate.Session; q#0yu"<
import org.hibernate.criterion.DetachedCriteria; pW&8 =Ew
import org.hibernate.criterion.Projections; 0a+U >S#
import C?rb}(m
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org.springframework.orm.hibernate3.HibernateCallback; aSeh?2n8
import HmV JkkksJ
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org.springframework.orm.hibernate3.support.HibernateDaoS _Ry
@iVEnb.'
upport; ?aZ\Dg{
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import com.javaeye.common.util.PaginationSupport; 2~)q080jh
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public abstract class AbstractManager extends j2|UuWU
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HibernateDaoSupport { I^QB`%v5
&qV_|f;
privateboolean cacheQueries = false; ++}#pl8e
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privateString queryCacheRegion; b~+\\,q}
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publicvoid setCacheQueries(boolean ([ hd
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cacheQueries){ qjR p5
this.cacheQueries = cacheQueries; =V^8RlBi
} 0[s<!k9=
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publicvoid setQueryCacheRegion(String AH
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queryCacheRegion){ -<5H8P-
this.queryCacheRegion = l 4cTN
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queryCacheRegion; HF%)ip+
} (<yQA. M
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publicvoid save(finalObject entity){ <-|g>
getHibernateTemplate().save(entity); h='@Q_1Sb
} <gSZ<T
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publicvoid persist(finalObject entity){ Y;8.(0r/
getHibernateTemplate().save(entity); BeM|1pe.
} !7uFH PK-
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publicvoid update(finalObject entity){ ;4(FS
getHibernateTemplate().update(entity); ACH!Gw~
} y/ah<Y0(
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publicvoid delete(finalObject entity){ E2|c;{c
getHibernateTemplate().delete(entity); W.<I:q`eO
} J]Qbg7|
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publicObject load(finalClass entity, !%YV0O0
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finalSerializable id){ "cX*GTNi8
return getHibernateTemplate().load V,
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(entity, id); 9,Ug
} j*1O(p+
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publicObject get(finalClass entity, f@J-6uQ7w
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finalSerializable id){ t/:]\|]WB
return getHibernateTemplate().get %-[U;pJe;
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(entity, id); V:
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} ,xIWyI.
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publicList findAll(finalClass entity){ wz5*?[4
return getHibernateTemplate().find("from 0t}&32lL&
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" + entity.getName()); KfLp cV
} WUqfY?5
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publicList findByNamedQuery(finalString XDq*nA8#5B
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namedQuery){ Kg;1%J>ee
return getHibernateTemplate *.Ceb%W7C
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().findByNamedQuery(namedQuery); _cH 7lO[
} c*x5t"{
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publicList findByNamedQuery(finalString query, !`#xFRHe
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finalObject parameter){ +t PqU6
return getHibernateTemplate '#0'_9}
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().findByNamedQuery(query, parameter); @I|gA
} bT{iei]?
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publicList findByNamedQuery(finalString query, ?)B\0` %*'
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finalObject[] parameters){ GFBku^pi
return getHibernateTemplate Q#rj>+?
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().findByNamedQuery(query, parameters); Q{+&3KXH
} }Qm: g
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publicList find(finalString query){ DJf!{:b)
return getHibernateTemplate().find *_7%n-k
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(query); 8z
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} rik0F
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publicList find(finalString query, finalObject 2bk~6Osp
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parameter){ ,P9q[
return getHibernateTemplate().find \P|PAU@,
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(query, parameter); ("B[P/
} Wc+)EX~KS
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public PaginationSupport findPageByCriteria oMV<Yn_<
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(final DetachedCriteria detachedCriteria){ /
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return findPageByCriteria hf~'EdU
.v{ok,&
(detachedCriteria, PaginationSupport.PAGESIZE, 0); o1kY|cnGH
} 89[5a
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public PaginationSupport findPageByCriteria +bw>9VmG
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(final DetachedCriteria detachedCriteria, finalint hc;8Vsa
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startIndex){ j!:^+F/
return findPageByCriteria &6`h%;a/&
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(detachedCriteria, PaginationSupport.PAGESIZE, EBX+fzjQo
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startIndex); fGtUr_D
} k_hV.CV
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public PaginationSupport findPageByCriteria :q0TS>l
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(final DetachedCriteria detachedCriteria, finalint S_VZ^1X]
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pageSize, eiV[y^?
finalint startIndex){ "[rChso
return(PaginationSupport) *|T]('xwC
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>@/
getHibernateTemplate().execute(new HibernateCallback(){ ,MxTT!9Su
publicObject doInHibernate qQu}4Ye>
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(Session session)throws HibernateException { }9GD'N?4
Criteria criteria = |ZAR!u&0
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detachedCriteria.getExecutableCriteria(session); S}Q/CT?au
int totalCount = VM1`:1Z:$
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((Integer) criteria.setProjection(Projections.rowCount Qt@_C*,P
/Jjub3>Q
()).uniqueResult()).intValue(); KTm^0:V[Oy
criteria.setProjection PYYK R
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(null); ?9Eshw2
List items = <GbF4\ue
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criteria.setFirstResult(startIndex).setMaxResults _qq> 43
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(pageSize).list(); 0GtL6M@pP
PaginationSupport ps = ^}+qd1r
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new PaginationSupport(items, totalCount, pageSize, avmuI^LLs
4'ym vR
startIndex); L"|~,SVF
return ps; jIMT&5k
} -_bnGY%,
}, true); *f[nge&.
} G^`IfF-j
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public List findAllByCriteria(final ETw7/S${
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DetachedCriteria detachedCriteria){ J3F-Yl|
return(List) getHibernateTemplate i|]Kw9
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().execute(new HibernateCallback(){ /A8ua=Kn
publicObject doInHibernate (aAv7kB&
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(Session session)throws HibernateException { Uq:WW1=kh
Criteria criteria = G% |$3
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detachedCriteria.getExecutableCriteria(session); q`HuVilNH
return criteria.list(); _.9):i2<SF
} x}Y
}, true); -VqZw&"
} TSGJ2u5ie%
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public int getCountByCriteria(final uANG_sX^n
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DetachedCriteria detachedCriteria){ .l| [e
Integer count = (Integer) 66P'87G
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getHibernateTemplate().execute(new HibernateCallback(){ WIe7>wkC
publicObject doInHibernate cBZKt
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(Session session)throws HibernateException { x)Y?kVw21"
Criteria criteria = iP7
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detachedCriteria.getExecutableCriteria(session); CFm(
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return NUlp4i~Q
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criteria.setProjection(Projections.rowCount S>-x<'Os
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()).uniqueResult(); ! :[`>=!
} :bh#,]'
}, true); J**-q(>
return count.intValue(); B6N/nCvHK
} SdOa#U)
} E[:eMJR
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用户在web层构造查询条件detachedCriteria,和可选的 |WiE`&?xP
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 z%)~s/2Rs
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PaginationSupport的实例ps。 1V\tKDM
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ps.getItems()得到已分页好的结果集 o!]muO*Rm
ps.getIndexes()得到分页索引的数组 QKW\z aG
ps.getTotalCount()得到总结果数 5r&bk`
ps.getStartIndex()当前分页索引 bW]7$?acv
ps.getNextIndex()下一页索引 HE;}B!>
ps.getPreviousIndex()上一页索引 iyA=d{S;V
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 J0ysZ]
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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 Oe)d|6=
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一下代码重构了。 KKBrw+)AJ
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我把原本我的做法也提供出来供大家讨论吧: N)I9NM[
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首先,为了实现分页查询,我封装了一个Page类: Bi.,@7|>
java代码: Ulf'gD4e
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/*Created on 2005-4-14*/ !^yH]v
package org.flyware.util.page; <y
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/** 6"h,0rR
* @author Joa diz=|g=w
* Wbq0K6X
*/ -> ^Ex`
publicclass Page { URd0|?t9^L
w4nU86oZYl
/** imply if the page has previous page */ w)rd--9f
privateboolean hasPrePage; @%'1Jd7-Wp
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/** imply if the page has next page */ HzMr
privateboolean hasNextPage; 9{GEq@`7
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/** the number of every page */ `hl8j\HV<}
privateint everyPage; eh39"s
d-sT+4o}
/** the total page number */ Sl;[9l2
privateint totalPage; 22T\-g{
zA>LrtyK(=
/** the number of current page */ g@O H,h/
privateint currentPage; E0*KKo%
q4EOI
/** the begin index of the records by the current :`>$B?x+
k-Z:z?M
query */ :MP*Xy\7&J
privateint beginIndex; w+wg)$i
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/** The default constructor */ Ol
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public Page(){ V0<g$,W=
3;O4o]`
} ;e"dxAUe!^
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/** construct the page by everyPage '8yC wk
* @param everyPage 9+iz+
* */ UhKd o
public Page(int everyPage){ ri`;
this.everyPage = everyPage; uq2C|=M-x\
} 7>E>`Nc6
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/** The whole constructor */ Z[9t?ePL
public Page(boolean hasPrePage, boolean hasNextPage, i'QR-B&Z
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int everyPage, int totalPage, GBl[s,g[|
int currentPage, int beginIndex){ :jf/$]p
this.hasPrePage = hasPrePage; Zsn@O2
this.hasNextPage = hasNextPage; |ms.
this.everyPage = everyPage; Xw#"?B(M]
this.totalPage = totalPage; 6l PuYEmT
this.currentPage = currentPage; PavW@
this.beginIndex = beginIndex; kz/"5gX:
} B k*Rz4Oa
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/** Sy/Z}H
* @return sVpET
* Returns the beginIndex. &P,uK+C4
*/ ' Tk4P{
publicint getBeginIndex(){ l>?f+70
return beginIndex; HUChg{[
} jqj4(J@%yr
Uc,J+j0F
/** v5 @9
* @param beginIndex BM{*5Lf
* The beginIndex to set. >m:n6M'r
*/ 8(ot<3(D
publicvoid setBeginIndex(int beginIndex){ 6M
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this.beginIndex = beginIndex; ?t/G@
} `TYC]9
1bFGoLAEFl
/** ?iZM.$![
* @return e"%uOuIYX
* Returns the currentPage. ckb(+*+l
*/ 1%C EUE
publicint getCurrentPage(){ qg/FI#r
return currentPage; id9 XwWV
} >,QCKZH
lGt:.p{NG
/** %^d<go^
* @param currentPage =CW> ;h]
* The currentPage to set. (<
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*/ jz~#K;3=,
publicvoid setCurrentPage(int currentPage){ Zd'Yu{<_2N
this.currentPage = currentPage; /:^nG+
} O+|ipw*B%
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/** 73B[|J*
* @return '"+Gn52#
* Returns the everyPage. %JH/|mA&|
*/ lcLDCt?
publicint getEveryPage(){ E+ |K3EJ
return everyPage; %gQUog
} <d"nz:e
w?zy/+N~
/** ;B;@MD,B
* @param everyPage +_k A&Q(t
* The everyPage to set. sv&^sARN
*/ =1k%T {>
publicvoid setEveryPage(int everyPage){ MkHkM
this.everyPage = everyPage; en/ h`h]h
} g\?v 5
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/** t%G.i@{pkp
* @return ^eyVEN
* Returns the hasNextPage. OSfT\8YA
*/ ,(-V<>/*.|
publicboolean getHasNextPage(){ ~1E!Co
return hasNextPage; .jg@UAK
} *>"NUHq
<;yS&8
/** *N4/M%1P
* @param hasNextPage '&hd^9]Lo
* The hasNextPage to set. SSCs96
*/ 0g6sGz=
publicvoid setHasNextPage(boolean hasNextPage){ OjAdY\
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this.hasNextPage = hasNextPage; n.qT7d(
} IU5T5p
ke!
/** G3`9'-2q@c
* @return VKZP\]$XG
* Returns the hasPrePage. hJ]Oa7r
*/ |/H?\]7
publicboolean getHasPrePage(){ =4'V}p
return hasPrePage; \+nV~Pi"A
} &tvtL
a]7g\rg)
/** :aBxyS*}G
* @param hasPrePage ,}]v7DD
* The hasPrePage to set. M]p-<R\
*/ k7Qs#L
publicvoid setHasPrePage(boolean hasPrePage){ `A%WCd60Tc
this.hasPrePage = hasPrePage; tc[z/
} =Gu&0f
u8.Tu7~
/** .)$MZyo
* @return Returns the totalPage. z/+{QBen8
* EPH
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*/ +or<(%o @
publicint getTotalPage(){ OJ"./*H
return totalPage; e ><0crb
} J _dgP[
{J
izCUo_'
/** 3N-pND0>p
* @param totalPage $[Z~BfSQ
* The totalPage to set. eUZk|be
*/ #) :.1Z?
publicvoid setTotalPage(int totalPage){ %cg| KB"l
this.totalPage = totalPage; .{c7 I!8
} A.("jb@I
,b&hLht
} .#bf9JOE
jc )7FE
g hmn3
-e}(\
` 6*]c n#(
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 lH`TF_
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个PageUtil,负责对Page对象进行构造: _J!&R:]$
java代码: 2aCf?l(
jk&xzJH.
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/*Created on 2005-4-14*/ wEM=Tr/h
package org.flyware.util.page; [.fh2XrVM
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import org.apache.commons.logging.Log; @L~erg>8=
import org.apache.commons.logging.LogFactory; ]"HaE-`%
!CX WoM
/** *!$Z5Im
* @author Joa a-E}3a
* -$o0P'Vx
*/ 7`;f<QNo
publicclass PageUtil { iLZY6?_^
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privatestaticfinal Log logger = LogFactory.getLog |@'O3KA
/P@%{y
(PageUtil.class); cZ?$_;=
3k9n*jY0
/** L55UeP\
* Use the origin page to create a new page rkR5>S( 2M
* @param page D0xQXC3$`
* @param totalRecords qjhV/fsfb
* @return :=;{w~D
*/ }R#W<4:
publicstatic Page createPage(Page page, int Ve|:k5z
f0sGE5
totalRecords){ "E\mj'k
return createPage(page.getEveryPage(), .gDq+~r8O
$Q8
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page.getCurrentPage(), totalRecords); 5[SwF&zZ
} SDil\x
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/** >*h+N?
m
* the basic page utils not including exception a24 AmoWx
}q@#M8 b
handler i,*m(C@F}
* @param everyPage 9;U?_
* @param currentPage ;\2Z?Kq
* @param totalRecords 4\&Y;upy+
* @return page F!EiF&[\J
*/ QcQ%A%VIV
publicstatic Page createPage(int everyPage, int zq{UkoME
I_v}}h{
currentPage, int totalRecords){ &N/t%q
everyPage = getEveryPage(everyPage); ?=M?v;8
currentPage = getCurrentPage(currentPage); 4)8VmCW
int beginIndex = getBeginIndex(everyPage, A)sYde(
{m>ylE
currentPage); kaekH*m~
int totalPage = getTotalPage(everyPage, *C5`LgeX
IB[$~sGe
totalRecords); Pn">fWRCx
boolean hasNextPage = hasNextPage(currentPage, 0dC5
-/+
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totalPage); Blzvn19'h
boolean hasPrePage = hasPrePage(currentPage); I61S0lz/
g) u%?T
returnnew Page(hasPrePage, hasNextPage, Vz/w.%_g
everyPage, totalPage, _=s9o/Cn]
currentPage, -Y/i
h(I^
O+=%Mz(l
beginIndex); L/tn;0
} BM,hcTr?
i)z|=
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privatestaticint getEveryPage(int everyPage){ Uv
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return everyPage == 0 ? 10 : everyPage; }<A.zwB<i
} Cr7Zi>sd<!
6^]|
privatestaticint getCurrentPage(int currentPage){ ~#*C,4m
return currentPage == 0 ? 1 : currentPage; *pJGp:{6V?
} ^)gyKl:E'
8mreHa
privatestaticint getBeginIndex(int everyPage, int o2ggHZe/=@
Bxm,?=h
currentPage){ WMa0L&C~v
return(currentPage - 1) * everyPage; MMFwT(l<1
} =WY'n
l'
1z-.e$&z
privatestaticint getTotalPage(int everyPage, int Kk8}m;
lWId
0eNS
totalRecords){ `sYFQ+D#O
int totalPage = 0; M@A3+v%K
aDNB~CwZZ
if(totalRecords % everyPage == 0) ls
5iE
totalPage = totalRecords / everyPage; {'O><4
else SO0\d0?u
totalPage = totalRecords / everyPage + 1 ; $~G,T
g
(E0
return totalPage; njy2pDC@
} :jl*Y-mM
C:J;'[,S
privatestaticboolean hasPrePage(int currentPage){ fkzSX8a9}
return currentPage == 1 ? false : true; 2H|:/y
} /e '3\,2_
p,fV .5q
privatestaticboolean hasNextPage(int currentPage, Wm}c-GD
V^2_]VFj
int totalPage){ =#G
2}8mQD
return currentPage == totalPage || totalPage == N*-tBz
{q0+PzgP
0 ? false : true; u<BU4c/p
} -&8( MT*
l'+3
6
'cs(gc0
} j?.F-ar
F<* / J]
1VX3pkUET
~wb1sn3
v03cQw\"WE
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 6$k#B ~~
X1|
+9
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
7=6:ZSI
q9/v\~m
做法如下: AFz:%m
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 s:U:Dv
Nn. 9J
的信息,和一个结果集List: dDa V2:4E
java代码: ~`OX}h/Z
?.?)5
&4
JtL>mH
/*Created on 2005-6-13*/ t}q
e_c
package com.adt.bo; ZLkl:'E_
DK4yAR,g
import java.util.List; 1X?ro;
.Mq#88o.*
import org.flyware.util.page.Page; &K9;GZS?
&uNec(c
/** _ .v G)
* @author Joa ,"%C.9a
*/ Z,).)y#B
publicclass Result { Ma^jy.
_\WR3Q!V
private Page page; Dh
I{&$O/
.G8`Ut Z
private List content; a1cX+{W
|`T(:ZKXZ2
/** CY1WT
* The default constructor +Iyyk02V
*/ r6DLShP-Ur
public Result(){ j_8 Y Fz5
super(); !vSI"$xd
} B]rdgjz*
s.2f'i+
/** smn"]K
* The constructor using fields MpCPY"WLL
* nQF&^1n
* @param page Qd}n4KF\
* @param content @Kpm&vd(
*/ ;vH2r~
public Result(Page page, List content){ 0]DOiA
this.page = page; 8?yIixhw
this.content = content; .hT>a<
} O =Z}DGa+
.a%6A#<X
/** *[Hp&6f
* @return Returns the content. m%HT)`>bg
*/ p*g Fr hm
publicList getContent(){ 02J/=AC5
return content; t;8)M$
p
} DzZF*ylQ5P
uF7vba$
/** t7Q$
* @return Returns the page. Y)rK'OY'
*/
R3>q ]
public Page getPage(){ }LUvh
return page; F&Md+2
} xIM,0xM2
3q]0gU&??
/** VE\L&d2S
* @param content QK-aH1r
* The content to set. H,7='n7"
*/ "#d$$ 8
public void setContent(List content){ 3lUVDNbZ
this.content = content; Vk6c^/v
} Etz#+R&*
V6g*"e/8
/** T^A(v(^D
* @param page o|xf2k
* The page to set. { 53FR
*/ ` H'G"V
publicvoid setPage(Page page){ TFSdb\g
this.page = page; #7uH>\r
}
+25}X{r$_
} #VQZ"7nI@
VfnL-bDGV
W|PAI[N
j=0kxvp
l)u%`Hcn
2. 编写业务逻辑接口,并实现它(UserManager, |IAx!Z-P
ndSu-8?L
UserManagerImpl) E>fY,*0
java代码: nW=6nCyvo
x;mw?B[
9{pT)(Wnb
/*Created on 2005-7-15*/ 8lF9LZ8
package com.adt.service; }QE.|.fA1
;}B=g/C
import net.sf.hibernate.HibernateException; m$8siF{<q
#qd!_oN
import org.flyware.util.page.Page; >tg)F|@
4H8r[
import com.adt.bo.Result; (Jq m9
5_^d3LOT0x
/** i\xs!QU
* @author Joa hb[ThQ
*/ ?$pNd uE
publicinterface UserManager { @nH3nn
w-).HPe
public Result listUser(Page page)throws jFQ y[k-B
!'$*Z(
HibernateException; frcAXh9
bJ2-lU% ;2
} ]OpGD5jZ
KloX.y)q
xW"O|x$6
S^s-md>
Ar%*NxX
java代码: M6-uTmN:d
$QiMA,
p{E(RsA
/*Created on 2005-7-15*/ U6JD^G=qR,
package com.adt.service.impl; ?V`-z#y7
3W'fEh5
import java.util.List; ;MfqI/B{
|$
PA
import net.sf.hibernate.HibernateException; < F5VJ
_a&gbSQv
import org.flyware.util.page.Page; &v:zS$m>
import org.flyware.util.page.PageUtil; JuJW]E Q
Uw4iWcC
import com.adt.bo.Result; BA
a:!p
import com.adt.dao.UserDAO; ,ei9 ?9J1
import com.adt.exception.ObjectNotFoundException; 6*,55,y
import com.adt.service.UserManager; \3vQXt\dM$
Zbo4{.#
/** RFw0u 0Nrz
* @author Joa 7(/yyZQnZ
*/ aZf/WiR2
publicclass UserManagerImpl implements UserManager { (j>`+F5f
ET[5`z
private UserDAO userDAO; SU%O \4Ty
.{gDw
/** m{>1#1;$t
* @param userDAO The userDAO to set. Z|K HF"
*/ |QS|\8g{0V
publicvoid setUserDAO(UserDAO userDAO){ 1c,#`\Iikd
this.userDAO = userDAO; gwB,*.z
} MJX
ny4n
% )V=)l.j
/* (non-Javadoc) 7sVM[lr<
* @see com.adt.service.UserManager#listUser O+!4KNN.-
sm##owI
(org.flyware.util.page.Page)
qiOtbH=
*/
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public Result listUser(Page page)throws ,DEq"VW_
.BxI~d^
HibernateException, ObjectNotFoundException { <.`i,|?MHS
int totalRecords = userDAO.getUserCount(); 9@1n:X
if(totalRecords == 0) W~H`{x%Av>
throw new ObjectNotFoundException 8 n[(\f:
j*>]HNo&
("userNotExist"); "OwM'
n8
page = PageUtil.createPage(page, totalRecords); :U\*4l
List users = userDAO.getUserByPage(page); |kmP#`P~
returnnew Result(page, users); Jk{SlH3'
} Gd!_9S`68
km>ZhsqD
} /Ey%aA4v
=U84*HAv
$`OyGeq"T
d/GSG%zB
tnpEfi-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 IV~)BW leT
C32*RNG?U
询,接下来编写UserDAO的代码: f)vnm*&-
3. UserDAO 和 UserDAOImpl: [fCnq
java代码: aVr(*s;/
'(iPI
%nJo:/
/*Created on 2005-7-15*/ dr#%~I
package com.adt.dao; e!Z}aOeE
")ys!V9
import java.util.List; "3_X$`v"!
t=lDN'\P
import org.flyware.util.page.Page; w[a(I}x
5_A*IC]
import net.sf.hibernate.HibernateException; z81dm
i&(1<S>P
/** v$\<L|
* @author Joa m p_7$#{l
*/ a2?@OJ
publicinterface UserDAO extends BaseDAO { ['>ZC3?"h
!0pK8k&MG
publicList getUserByName(String name)throws BZLIi
O
.{eMN[ n@
HibernateException; ]@y%j'e
3L2NenJB
publicint getUserCount()throws HibernateException; r5[pT(XT]
8(ZQM01;
publicList getUserByPage(Page page)throws kjQW9QJ<
&qY]W=9uK
HibernateException; F<h+d917
{$t*XTY6R
} %1
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[PXq<ST
{KDN|o+%
;t>4VA
=LY`K#
java代码:
9PV]bt,
_KloX{a
KKQT?/ {b
/*Created on 2005-7-15*/ =84EX<B
package com.adt.dao.impl; l4mRNYv)z
W*iTg%a\k
import java.util.List; f>xi (0
;HYEJ3
import org.flyware.util.page.Page; IAbQgBvUD
ta5_k&3N
import net.sf.hibernate.HibernateException; NHUJ:j@
import net.sf.hibernate.Query; 1mHS -oI9J
+<$nZ=,hsy
import com.adt.dao.UserDAO; S/*\j7cj
@gqZiFM)
/** Rkg)yme!N
* @author Joa An}RD73!w
*/ h+Lpj^<2a
public class UserDAOImpl extends BaseDAOHibernateImpl {tOf0W|
\{Q_\s&)
implements UserDAO { Z[&FIG%tV
P )oNNY6}
/* (non-Javadoc) D
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* @see com.adt.dao.UserDAO#getUserByName #Rfcp!
#|+4 `Gf^
(java.lang.String) IlO,Ql
*/ 6jm?d"9
publicList getUserByName(String name)throws 2aR9vmR
L9^M?.a
HibernateException { &2%|?f|
String querySentence = "FROM user in class Mb"y{Fox
[QMN0#(h
com.adt.po.User WHERE user.name=:name"; @x*xgf
Query query = getSession().createQuery {m3#1iV9
Y6Y"fb%K
(querySentence); C(h<s
e?
query.setParameter("name", name); i@D4bd9lR
return query.list(); T)<^S(57
} 96;5
>Mh\jt\
/* (non-Javadoc) fp(zd;BSQ
* @see com.adt.dao.UserDAO#getUserCount() $;(@0UDE
*/ ab9ec Z
publicint getUserCount()throws HibernateException { %H{;wVjK
int count = 0; }oiNgs/N
String querySentence = "SELECT count(*) FROM e*`ht+
gREk,4DAv
user in class com.adt.po.User";
s5G`?/
Query query = getSession().createQuery }^Sk.:;n3
*@^@7`W
(querySentence); K:XP;#OsP
count = ((Integer)query.iterate().next E_'H=QN c
V=fh;p
()).intValue(); AB3OG*C9
return count; 8kcMgCO
} WZHw(BN{+
8JQ\eF$ma
/* (non-Javadoc) B1FJAKI);
* @see com.adt.dao.UserDAO#getUserByPage +-),E.
:J@3:+sr
(org.flyware.util.page.Page) `#W+pO
*/ IYtiX
publicList getUserByPage(Page page)throws [\eVX`it
mA.,.<xE@
HibernateException { 6~jAh@-
String querySentence = "FROM user in class Hn(Eut7%
#Vmf
6
com.adt.po.User"; V'RbTFb9Z
Query query = getSession().createQuery \K"7U
ZDL1H3;R
(querySentence); +w.$"dF!
query.setFirstResult(page.getBeginIndex()) XUVj<U
.setMaxResults(page.getEveryPage()); y]PuY\+
return query.list(); \p.yR.
} >l%8d'=Jl
w-R.)
} 8oI|Z=
/;}%E
JvvN>bg
j[R.UB3J
S[7^#O.)
至此,一个完整的分页程序完成。前台的只需要调用 tw.GBR
*aS+XnT/
userManager.listUser(page)即可得到一个Page对象和结果集对象 cK\
u
|,=^P`#%
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~Gh7i>n*
1,h:|
webwork,甚至可以直接在配置文件中指定。 X=1o$:7
N2HD=[*cr
下面给出一个webwork调用示例: =#pYd~
java代码: PCL
;Z
9,JM$ Y
{
&L+.5i
/*Created on 2005-6-17*/ G!B:>P|\l
package com.adt.action.user; BtbU?t
^$%
Sg//
import java.util.List; (y6}xOa(
^Lc\{,m
import org.apache.commons.logging.Log; _[E+D0A
import org.apache.commons.logging.LogFactory; 1|w@f&W"
import org.flyware.util.page.Page; k]$oir
+ansN~3
import com.adt.bo.Result; =+mb@#="m
import com.adt.service.UserService; uJH[C>
import com.opensymphony.xwork.Action; 7$g$p&,VX
w1-P6cf
/** K, !
V _
* @author Joa Nc4;2~XwRp
*/ h/|p`MP\1
publicclass ListUser implementsAction{ Pf,@U'f|
JN9>nC!Zy_
privatestaticfinal Log logger = LogFactory.getLog ^vT!24sK
VZr:yE
(ListUser.class); >w7KOVbN3
Ng !d6]
private UserService userService; !Tv3WQ@
V7nOT*N:Q
private Page page; Mh~}RA"H
F xm:m
privateList users; ?$)5NQB%
RzL(Gnb
/* |BZrV3;H
* (non-Javadoc) =+wd"Bu
* !dGu0wE
* @see com.opensymphony.xwork.Action#execute() i@5Fne
*/
6(-s@{
publicString execute()throwsException{ 3 1-p/
Result result = userService.listUser(page); ^Z;zA@[wt
page = result.getPage(); 7mdd}L^h
Z
users = result.getContent(); K.mxF,H
return SUCCESS; yj_> G
} 6*>Lud
@j}%{Km]Y
/** jMTM:~0N
* @return Returns the page. /N_:npbJF
*/ LOi}\O8
public Page getPage(){ wxc#)W
return page; <]1,L%
} wz69Yw7
OrM1eP"I
/** r#4/~a5i~
* @return Returns the users. 37jxl+
*/ :p: C
publicList getUsers(){ {LF4_9 =
return users; CKK}Z;~:
} 77)WNL/
x
RM `qC
/** $+7uB-KsU
* @param page L0!CHP/nRS
* The page to set. W!? h2[
*/ Qw'905;(
publicvoid setPage(Page page){ nDC0^&
this.page = page; Wj(#!\ 7F
} 9|}Pf_5]%[
}/vW"&h-
/** Yjjh}R#
* @param users <R@,wzK
* The users to set. kc^,V|Nbq6
*/ @pYEzizP7
publicvoid setUsers(List users){ iI IXv
this.users = users; 'v V7@@
} pCh v;
Wvr{l
/** s b;q)Rh
* @param userService ?![[la+f
* The userService to set. 0Z8"f_GK
*/ E(PBV
publicvoid setUserService(UserService userService){ 8\lh'8
this.userService = userService; ciS,
} =zyA~}M2
} BtC*]WB"_'
'q)g,2B%
~.%HZzR6&
<ErX<(0`ig
Fa )QDBz)
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, *$<W"@%^J
[^5;XD:%&l
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 a9.yuSzL
_rwJ:r
么只需要: aaFT
java代码: ;Nj9,Va(t
aE`d[dSG
+GI906K
<?xml version="1.0"?> Q<
:RLKVT
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork v.jxG{~.
"ntP92 8
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $mn0I69
D=#RQ-
1.0.dtd"> ",$_\l
f_jhQ..g<g
<xwork> AzOs/q8O
;2<5^hgk
<package name="user" extends="webwork- P"Al*{:J
(h3L=
interceptors"> m$W>~
E&P2E3P
<!-- The default interceptor stack name C_Ewu*T7
sCFxn
--> i3,IEN
<default-interceptor-ref Mqr_w!8d
3T2]V?
name="myDefaultWebStack"/> @b,Az{EH
9 %T??-
<action name="listUser" "=djo+y
5G f@n/M"
class="com.adt.action.user.ListUser"> T+<.KvO-
<param -!j6&
q<dG}aj
name="page.everyPage">10</param> *5%vU|9b
<result nF,F#V8l
&<PIm
name="success">/user/user_list.jsp</result> Qn!mS[l
</action> $^ws#}j
cq4~(PXTg
</package> W,<q!<z\t
!!y]pMjJa@
</xwork> t}YcB`q)
@Vre)OrN#
`x[Is$
6O7s^d&K
Wo1xZZ
4dX{an]Cz
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 X7},|cmD_
mM,HMrgLqK
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 q>$MqKWM
51jgx,-|$
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 KewW8H~tb
X4
Arn,
AE0uBv
vYed_'_
~3F'X
我写的一个用于分页的类,用了泛型了,hoho uuC ["Z
Jka>Er
java代码: {zwH3)|Hn
vd%g'fTy9
4)S99|1
package com.intokr.util; zjpZ] $
: ky`)F`
import java.util.List; wjA
wJOw|
>JyS@j}
/** H7zN|NdNw
* 用于分页的类<br> jRJG .hcB5
* 可以用于传递查询的结果也可以用于传送查询的参数<br> xZ'fer`&
* 'C1lP)S5
* @version 0.01 ytZ o0pad
* @author cheng kxMvOB$
*/ paqGW]
public class Paginator<E> { *N">93:
privateint count = 0; // 总记录数 =;rLv7(a
privateint p = 1; // 页编号 SqM>xm
privateint num = 20; // 每页的记录数 0q}i5%m7
privateList<E> results = null; // 结果 Z0,jg)sA4
V}jGxt0
/** K*/oWYM]
* 结果总数 D*M `qPX~
*/ M/N8bIC! Q
publicint getCount(){ vO}r(kNJ
return count; PG&t~4QM`
} XF!L.' zH
JrzPDb`m
publicvoid setCount(int count){ PCviQ!X
this.count = count; #e'>9T
} m$T5lKn}U?
gHg=G+Q@
/** ;TAj;Tf]H
* 本结果所在的页码,从1开始 |N)Ik8
* $*#a;w7\C
* @return Returns the pageNo. 2u3Kyn
*/ ingG
publicint getP(){ {VcRur}&Y8
return p; =zkN63S
} -DI
>O/
Aa
~W,
/** (95|DCL
* if(p<=0) p=1 #T=iS(i
* Tagf7tw4
* @param p 'C]w3Rh'
*/ xl&@g)Jj
publicvoid setP(int p){ EXDDUqZ5\
if(p <= 0) C[J9 =!t
p = 1; -D`1z?zHra
this.p = p; qSY\a\.<
} &
l>nzJ5?
{wqT$( (<
/** bb6x} jR
* 每页记录数量 (GJtTp~2C4
*/ _Mw3>GNl
publicint getNum(){ D2$9$xeR
return num; F>fCp
} w!F>fcm
s<I)THC
/** AO-5>r
* if(num<1) num=1 IMf|/a9-
*/ 8 v/H;65
publicvoid setNum(int num){ tFmB`*!%
if(num < 1) 6,>$Jzs)5E
num = 1; K*~{M+lU7
this.num = num; 3=O [Q :8
} p<5]QV7st
Q((&Q?Vi
/** 6}"%>9
* 获得总页数 uo"<}>iJ
*/ \Zj%eW!m
publicint getPageNum(){ H*=cw<
return(count - 1) / num + 1; }z`x-(V
} ?;XO1cs
Rl?1|$%
/** .9J^\%JD
* 获得本页的开始编号,为 (p-1)*num+1 Zxebv#4
*/ UqK.b}s
publicint getStart(){ ]s\r3I]
return(p - 1) * num + 1; z !K2UTX
} 7HPwlS
jSI1tW8
/** wHLQfrl0
* @return Returns the results. E7X6RB b
*/ odhcD;^X1
publicList<E> getResults(){ mskG2mA
return results; 4.O) /0sU
} XZE(& (s
G5}_NS/
public void setResults(List<E> results){ b}!
cEJY
this.results = results; "wcaJ;Os
} +~8Lc'0aA
8zK#./0\
public String toString(){ 'uu*DgEr
StringBuilder buff = new StringBuilder ]IuZ T
"~4V(
(); 5rsz2;#p
buff.append("{"); zluq2r
buff.append("count:").append(count); \BHZRytQF
buff.append(",p:").append(p); ,rB(WKU
buff.append(",nump:").append(num); /YJo"\7
buff.append(",results:").append 01.q9AGy
GfONm6A
(results); L3eF BF/
buff.append("}"); ,DFN:uf=l
return buff.toString(); J!C \R5\
} @)pC3Vi^
<*5S7)]BP
} wB)y@w4k
;[y( 14g
+SFFwjI