Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 0Qf,@^zL*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 W')Yg5T
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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 zHM(!\8K
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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 UM"- nZ>[
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分页支持类: !Wntd\w
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java代码: -&zZtDd F
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package com.javaeye.common.util; f.KN-f8<F
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import java.util.List; j8^I z
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publicclass PaginationSupport { .YAT:;L
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publicfinalstaticint PAGESIZE = 30; @@Kp67Iv
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privateint pageSize = PAGESIZE; aC8} d
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privateList items; KQ% GIz x
];[}:f
privateint totalCount; Nk?
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privateint[] indexes = newint[0]; z!ZtzD]cb
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privateint startIndex = 0; y.mda:$~=
spH7 /5}
public PaginationSupport(List items, int On9A U:\
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totalCount){ *v^Jb/E315
setPageSize(PAGESIZE); gwuI-d^
setTotalCount(totalCount); ]8_NZHld
setItems(items); O:;w3u7;u
setStartIndex(0); '}53f2%gKa
} NX*Q F+
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public PaginationSupport(List items, int k(nW#*N_
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totalCount, int startIndex){ L,/%f<wd
setPageSize(PAGESIZE); $bR~+C
setTotalCount(totalCount); +{.WQA}z\
setItems(items); m+[Ux{$
setStartIndex(startIndex); jvL[
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} ~TD0zAA&
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public PaginationSupport(List items, int K($Npuu]
r#p9x[f<Y
totalCount, int pageSize, int startIndex){ &U#|uc!+
setPageSize(pageSize); `*R:gE=
setTotalCount(totalCount); ! n@KU!&k
setItems(items); |0b`fOS
setStartIndex(startIndex); Xl#ggub?
} e X|m
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publicList getItems(){ qR8Lh( "i
return items; hMO=#up&
} \ ~$#1D1f
;*Et[}3
publicvoid setItems(List items){ db7B^|Di
this.items = items; ",; H`V
} FvjPdN/L?R
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publicint getPageSize(){ #)O65GI
return pageSize; _Y;W0Z
} JK5gQ3C[
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publicvoid setPageSize(int pageSize){ bROLOf4S
this.pageSize = pageSize; BQMpHSJ_
} n{mfn*r.
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publicint getTotalCount(){ ?Z/V~,
return totalCount; n/:33DAB
} eD6fpe\(
@*((1(q
publicvoid setTotalCount(int totalCount){ Qp3_f8
if(totalCount > 0){ OQJ6e:BGt
this.totalCount = totalCount; q@8*Xa >
int count = totalCount / jQB9j
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pageSize; /82b S|
if(totalCount % pageSize > 0) s.C_Zf~3
count++; aqk!T%fg
indexes = newint[count]; UZ+<\+q3^
for(int i = 0; i < count; i++){ kt:!
7
indexes = pageSize * YIYmiv5
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i; ZUd-<y
} r;N|)
}else{ u'BaKWPS
this.totalCount = 0; (*iHf"=\
} [{,1=AB
} `[i r}+S
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publicint[] getIndexes(){ SwMc
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return indexes; XwaXdvmK
} q(84+{>B
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publicvoid setIndexes(int[] indexes){ $>LQ6|XRu
this.indexes = indexes; X'iWJ8
} wFZP,fQ9l
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publicint getStartIndex(){ 4.t-i5
return startIndex; %EB/b
} /%^#8<=|U
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publicvoid setStartIndex(int startIndex){ N~'c_l
if(totalCount <= 0) >z@0.pN]7
this.startIndex = 0; c\j/k[\<
elseif(startIndex >= totalCount) PEZ!n.'S
this.startIndex = indexes =UWI9M*sz
fz
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[indexes.length - 1]; 61U09s%\0
elseif(startIndex < 0) pEA:L$&
this.startIndex = 0; F:S}w
else{ S?2>Er
this.startIndex = indexes =T7.~W
Y.p;1"
[startIndex / pageSize]; oEpFuWp%A
} VI*$em O0
} >XfbP]
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publicint getNextIndex(){ yJIscwF
int nextIndex = getStartIndex() + ;aVZ"~a+\
9hyn`u.
pageSize; ;RlxD 4p
if(nextIndex >= totalCount) jmG~Un M
return getStartIndex(); CU!Dhm/U
else b&U62iq
return nextIndex; c7H^$_^ =
} }0y"F
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publicint getPreviousIndex(){ KMax$
int previousIndex = getStartIndex() - t%8BK>AHvw
G 01ON0
pageSize; A,!-{/w c
if(previousIndex < 0) &$H!@@09|w
return0; =7UsVn#o
else J#83 0r(-
return previousIndex; 2GG2jky{/
} TWX.D`W
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} 2&cT~ZX&'
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抽象业务类 wC'Szni
java代码: -mh3DhJ,
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/** xoME9u0x4
* Created on 2005-7-12 ~"A0Rs=
*/ r9XZ(0/p
package com.javaeye.common.business; s5.CFA
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import java.io.Serializable; BnY&f
import java.util.List; Q,Eo mt
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import org.hibernate.Criteria; kq-) ^,{y
import org.hibernate.HibernateException; o2ECG`^b
import org.hibernate.Session; DHRlWQox
import org.hibernate.criterion.DetachedCriteria; -Lg
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import org.hibernate.criterion.Projections; f6p/5]=J26
import dc'Y`e
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org.springframework.orm.hibernate3.HibernateCallback; ~}Pfu
import P$,Ke<
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org.springframework.orm.hibernate3.support.HibernateDaoS NHE18_v5
!VzC&>'v^9
upport; ~$J2g
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import com.javaeye.common.util.PaginationSupport; ~.|_ RdN
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public abstract class AbstractManager extends LR3*G7
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HibernateDaoSupport { y1#1Ne_
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privateboolean cacheQueries = false; \{D"
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privateString queryCacheRegion; ),!qTjD
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publicvoid setCacheQueries(boolean
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cacheQueries){ _e2=ado
this.cacheQueries = cacheQueries; }-`4DHgq
} G+m }MOQP7
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publicvoid setQueryCacheRegion(String 'c~4+o4co
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queryCacheRegion){ moE2G?R
this.queryCacheRegion = [N'h%1]\
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queryCacheRegion; VtohL+
} h@BY]80
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publicvoid save(finalObject entity){ y)<q/
getHibernateTemplate().save(entity); 2A!FDr~cdT
} ]_$[8#kg
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publicvoid persist(finalObject entity){ &e3.:[~_?
getHibernateTemplate().save(entity); &nK<:^n
} ./~(7o$
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publicvoid update(finalObject entity){ -n;}n:wL
getHibernateTemplate().update(entity); WY]s |2a
} d"Y{UE
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publicvoid delete(finalObject entity){ d d;T-wa}
getHibernateTemplate().delete(entity); %jM,W}2
} *lb<$E]="!
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publicObject load(finalClass entity, D&zle~" J
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finalSerializable id){ &c #N)U
return getHibernateTemplate().load T]$U""
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(entity, id); :gC#hmm^
} BJ0?kX@
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publicObject get(finalClass entity, 048kPXm`
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finalSerializable id){ ?X;RLpEc|A
return getHibernateTemplate().get hv+zGID7
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(entity, id); %XTI-B/K
} 2T`!v
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publicList findAll(finalClass entity){ Xm&L
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return getHibernateTemplate().find("from g,Y/M3>(
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" + entity.getName()); w*Ihk)
} "7`<~>9t.
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publicList findByNamedQuery(finalString &.ACd+Cd
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namedQuery){ }1xo-mUg,
return getHibernateTemplate A)KZa"EX
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().findByNamedQuery(namedQuery); ]%(2hY~i
} y> (w\K9W
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publicList findByNamedQuery(finalString query, (iGTACoF
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finalObject parameter){ A\;U3Zu
return getHibernateTemplate .sA.C]f
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().findByNamedQuery(query, parameter); hzC>~Ub5
} r_.S>]
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publicList findByNamedQuery(finalString query, SY8C4vb'h
B\n[.(].r
finalObject[] parameters){ F5#YOck&,
return getHibernateTemplate H:\k}*w
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().findByNamedQuery(query, parameters); aN=B]{!
} Er[A X.3
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publicList find(finalString query){ b>$S<td
return getHibernateTemplate().find 1nOCQ\$l
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(query); iR0y"Cii
} O1kl70,`R
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publicList find(finalString query, finalObject &~w}_Fjk
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parameter){ q,6DEz
return getHibernateTemplate().find P
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(query, parameter); {_dvx*M
} ,Lt[\_
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public PaginationSupport findPageByCriteria Xry47a
)
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(final DetachedCriteria detachedCriteria){ {BHO/q3
return findPageByCriteria G#1GXFDO{
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \|ao`MMaD<
} v.ui!|c
b u"!jHPB
public PaginationSupport findPageByCriteria a'z7(8$$
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(final DetachedCriteria detachedCriteria, finalint o`RKXfCq
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startIndex){ 6`-jPR
return findPageByCriteria JMM W
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(detachedCriteria, PaginationSupport.PAGESIZE, c0fo7|
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startIndex); <^uBoKB/f
} bs'n+:X`
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public PaginationSupport findPageByCriteria VD\=`r)nT
e0 T\tc
(final DetachedCriteria detachedCriteria, finalint A +)`ZTuO
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pageSize, FsryEHz
finalint startIndex){ n-OL0$Xu
return(PaginationSupport) "g#i'"qnW
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getHibernateTemplate().execute(new HibernateCallback(){ D#)b+7N-
publicObject doInHibernate E+JqWR5
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(Session session)throws HibernateException { ]$_NyAoBb
Criteria criteria = kSh( u
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detachedCriteria.getExecutableCriteria(session); !v0LBe4
int totalCount = /FJu)H..U
})?GzblI&
((Integer) criteria.setProjection(Projections.rowCount = 9]~yt
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()).uniqueResult()).intValue(); vZoaT|3
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criteria.setProjection eGHaY4|
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(null); O1mKe%'|
List items = VAu&@a`
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criteria.setFirstResult(startIndex).setMaxResults RdML3E
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(pageSize).list(); I
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PaginationSupport ps = }AH]
th
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new PaginationSupport(items, totalCount, pageSize, {!dVDf_
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startIndex); o.l-7
return ps; y;H-m>*%
} hfy_3} _
}, true); ,nB5/Lx
} J6aef^>
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public List findAllByCriteria(final A$:U'ZG_
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DetachedCriteria detachedCriteria){ /d<P-!fK
return(List) getHibernateTemplate Tyf`j,=
]`+HO=0
().execute(new HibernateCallback(){ H}bJ"(9$vC
publicObject doInHibernate OH(waKq2I
=rCIumqD-}
(Session session)throws HibernateException { V%
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Criteria criteria = r?
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[ ~&/s:Vvo
detachedCriteria.getExecutableCriteria(session); W]5w \
return criteria.list(); ?oHpFlj
} c|@bwat4
}, true); d,n 'n
} [e}]}t8m
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public int getCountByCriteria(final sI^Xb@'09$
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DetachedCriteria detachedCriteria){ <;Zmjeb+#
Integer count = (Integer) cP_.&!T
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getHibernateTemplate().execute(new HibernateCallback(){ o="M
publicObject doInHibernate zv,jM0-
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(Session session)throws HibernateException { o!ebs0
Criteria criteria = pohp&Tcm
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detachedCriteria.getExecutableCriteria(session); S2VA{9:m
return Q:k}Jl
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criteria.setProjection(Projections.rowCount Ks`J([(W&
T!WT;A
()).uniqueResult(); )"aV* "
} PKg@[<g43
}, true); U6fgo3RH
return count.intValue(); R3&Iu=g
} DjQFi
} A!WKnb_`
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用户在web层构造查询条件detachedCriteria,和可选的
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 MH9q ;?.J
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PaginationSupport的实例ps。 UJ7*j%XQz_
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ps.getItems()得到已分页好的结果集 3>`mI8$t
ps.getIndexes()得到分页索引的数组 }" %?et(
ps.getTotalCount()得到总结果数 EGU
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ps.getStartIndex()当前分页索引 HjD8u`qQ
ps.getNextIndex()下一页索引 hxd`OG<gF
ps.getPreviousIndex()上一页索引 Eq9x2
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 {~"/Y@&]R
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 !_D0vI;
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一下代码重构了。 4,gK[ dc
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我把原本我的做法也提供出来供大家讨论吧: *>'V1b4}
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首先,为了实现分页查询,我封装了一个Page类: })8N5C+KU
java代码: vB|hZTW
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/*Created on 2005-4-14*/ J76kkW`5
package org.flyware.util.page; QIvVcfM^
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/** JZ*/,|1}EC
* @author Joa ju8q?Nyhs
* MvHm)h
*/ j94=hJVKi
publicclass Page { BBRR)
KNpl:g3{<Q
/** imply if the page has previous page */ #;qdY[v
privateboolean hasPrePage; lN?qp'%H`
lC("y'
::
/** imply if the page has next page */ #+HJA42
privateboolean hasNextPage; xU>WEm2
RD'Q :W
/** the number of every page */ #crQ1p) \
privateint everyPage; 5Y'qaIFR
n :\~'+$
/** the total page number */ xH(lm2kvT
privateint totalPage; 9_rYBX
NAQAU
*yP
/** the number of current page */ #Z`q+@@]A
privateint currentPage; AFDq}*2Qb
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/** the begin index of the records by the current YYl 4"l
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query */ kmsb hYM)
privateint beginIndex; I{9QeRI
>WQMqQ^t@
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/** The default constructor */ st3l2Q
public Page(){ EZy)A$|
@6F#rz
} 3kIN~/<R+7
+N9X/QFKV
/** construct the page by everyPage ?{|q5n
* @param everyPage 6?mibvK
* */ ^HThN
public Page(int everyPage){ B^Nf #XN(
this.everyPage = everyPage; p7VTa~\zA
} ~u!|qM
&Gn 2tr
/** The whole constructor */ W5lR0)~#*
public Page(boolean hasPrePage, boolean hasNextPage, H*QIB_
#!qm ZN
c~$)UND^
int everyPage, int totalPage, Y1OkkcPb{
int currentPage, int beginIndex){ ,o{9$H5{
this.hasPrePage = hasPrePage; *:YiimOY"
this.hasNextPage = hasNextPage; "Hb"F?Yb
this.everyPage = everyPage; KRLQ #,9
this.totalPage = totalPage; >CgTs
this.currentPage = currentPage; 1i"WDu*h3
this.beginIndex = beginIndex; 5k3n\sqZA
} <fjX[l<Uz
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/** Z!#!Gu*V
* @return 1onM j
* Returns the beginIndex. z8~NZ;A
*/ \oXpi$
publicint getBeginIndex(){ +p_CN*10H
return beginIndex; ARVf[BAJ-*
} 2d(e:rh]
w d^':
/** ;%5N%0,
* @param beginIndex YTpSHpf@
* The beginIndex to set. /W30~y
*/ :P\7iW
publicvoid setBeginIndex(int beginIndex){ Ic:(Gi- %
this.beginIndex = beginIndex; dvx#q5f_S
} }DEg-j,F
B5VKs,g
/** ygS;$2m%2
* @return y$F'(b|)
* Returns the currentPage. AGO+p(6d=g
*/ <#y[gTJ<'>
publicint getCurrentPage(){ 3cyHfpx-W
return currentPage; ?|C2*?hZ+
} k>Vci{v
kr5">"7
/** }b"yU#`Q\
* @param currentPage Y3cMC)
* The currentPage to set. qu6D 5t
*/ D|L9Vs`
publicvoid setCurrentPage(int currentPage){ fZzoAzfv2
this.currentPage = currentPage; 2dcV"lY
} E`0?
UA0Bzoky;
/** 9y8&9<#
* @return ]z;I_-
* Returns the everyPage. +nhLIO{{L
*/ Mj?`j_X
publicint getEveryPage(){ /-qNh>v4
return everyPage; :&rt)/I
} k&q;JyUi
<QAFL uey
/** V-2(?auZd
* @param everyPage |t&>5HM
* The everyPage to set. _LUhZlw
*/ \0I_<
publicvoid setEveryPage(int everyPage){ ,RI Gc US
this.everyPage = everyPage; UiP"Ixg6
} 6|%?te x
\?ZB]*Fu
/** T|op$ s|
* @return fS:&Ak
];
* Returns the hasNextPage. Y%aCMP9j~9
*/ l^-];|Y
publicboolean getHasNextPage(){ ~i{(<.he
return hasNextPage; c(E{6g?
} v2\FA(BPn
)Y0!~#
`
/** (ejvF):|
* @param hasNextPage &|ex`nwc0
* The hasNextPage to set. rgv?gaQ>
*/ l
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publicvoid setHasNextPage(boolean hasNextPage){ {n.PF8A5X
this.hasNextPage = hasNextPage; El".I?E*
} 7\[@m3s
)5JFfp)#
/** |?xN\O^#}
* @return EIAc@$4
* Returns the hasPrePage. M,,bf[p$
*/ 8)3*6+D
publicboolean getHasPrePage(){ (9GWbB?
return hasPrePage; tBWrL{xLe
} rmm0/+jY
NiK4d{E&
/** E \EsWb
* @param hasPrePage glxsa8
* The hasPrePage to set. ~2N"#b&J
*/ _pG-qK
publicvoid setHasPrePage(boolean hasPrePage){ qLG&WB
this.hasPrePage = hasPrePage; RFc v^Xf
} nYSiS}?S.
|O+H[;TB6
/** 7#a-u<HF"
* @return Returns the totalPage. .bg~>T+<
* \fdv]f
*/ EwT"uL*V;
publicint getTotalPage(){ eA ?RK.e
return totalPage; I)[DTCJ~
} aCj&O:]=
:#ik. D
/** ^|>PA:%
* @param totalPage n\D&!y[]F
* The totalPage to set. P=Jo+4O
*/ uym*a4J
publicvoid setTotalPage(int totalPage){ 1#2 I
this.totalPage = totalPage; B{#I:Rs9
} (gU!=F?#m
)m)-o4c
} xml7Uarc
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m,w A:o$'
hEH?[>9
rfg'G&A(
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 `25yE/
69NeQ$](
个PageUtil,负责对Page对象进行构造: w3_>VIZJl
java代码: pa3{8x{9m
QO~P7r|A
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/*Created on 2005-4-14*/ 2- h{N
package org.flyware.util.page; KYI/
U_Ptqqt%
import org.apache.commons.logging.Log; -f^tE,-
import org.apache.commons.logging.LogFactory; P4'Q/Sj
I6av6t}
/** p)-^;=<B3
* @author Joa ,^< R{{{-A
* &h)yro
*/ SHgN~Um
publicclass PageUtil { 4l'fCZhA}
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privatestaticfinal Log logger = LogFactory.getLog ECuH%b^,
%)1?TU
(PageUtil.class); i9|Sa6vuI
fU}ub2_in
/** "+nRGEs6
* Use the origin page to create a new page U9 s&
* @param page ?e4YGOe.
* @param totalRecords t%)7t9j
* @return @b%=H/5\
*/ k]|~>9eY]
publicstatic Page createPage(Page page, int $8h%a
8I
o5PO=AN
totalRecords){ 9Q.Yl&A
return createPage(page.getEveryPage(), AV]2euyn
my1@41
H
page.getCurrentPage(), totalRecords); JyK3{wYS
} 3;9^
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/** 4F:\-O
* the basic page utils not including exception f'RX6$}\1X
eM6<%?b
handler Dml;#'IF3
* @param everyPage #:_Kws>+
* @param currentPage G~a ZJ,
* @param totalRecords Dx?,=~W9
* @return page O=t_yy
*/ a58H9w"u)
publicstatic Page createPage(int everyPage, int =y*IfG9b
t{9GVLZ
currentPage, int totalRecords){ 0Mm)`!TLSW
everyPage = getEveryPage(everyPage); g:@#@1rB6
currentPage = getCurrentPage(currentPage); oZgjQM$YP
int beginIndex = getBeginIndex(everyPage, h(dvZ=
%
(%6P0*
currentPage); 9.-S(ZO
int totalPage = getTotalPage(everyPage, |HQW0
M|h3Wt~7
totalRecords); .p[ux vp
boolean hasNextPage = hasNextPage(currentPage, "&u@d~`-n
H*R"ntI?w
totalPage); Bsvr?|L\
boolean hasPrePage = hasPrePage(currentPage); IEi^kJflU
uGG t\.$]s
returnnew Page(hasPrePage, hasNextPage, C}Cs8eUn
everyPage, totalPage, =UQ3HQD
currentPage, Rhs/3O8k
7n<{tM
beginIndex);
UI0VtR]
} +O{*M9B
Zu[su>\
privatestaticint getEveryPage(int everyPage){ 6nvz8f3*r]
return everyPage == 0 ? 10 : everyPage; Yj49t_$b
} v\ )W?i*l
M%m4i9~!?
privatestaticint getCurrentPage(int currentPage){ (L&d!$,Dv
return currentPage == 0 ? 1 : currentPage; [z{1*Xc
} g!|kp?
;6$jf:2m
privatestaticint getBeginIndex(int everyPage, int KZE,bi:~
rb.N~
currentPage){ n_A3#d<9
return(currentPage - 1) * everyPage; vk^xT
} H1./x6Hr
S=5o
< 1
privatestaticint getTotalPage(int everyPage, int lL3U8}vn
+r2-S~f3N
totalRecords){ CA~-rv
int totalPage = 0; A;M'LM- M
g) jYFfGfH
if(totalRecords % everyPage == 0) ~$^XP.a.
totalPage = totalRecords / everyPage; }Sv:`9=
else 99QU3c<.
totalPage = totalRecords / everyPage + 1 ; 3=j"=-=
PJH&
return totalPage; 8l`*]1.W<
} f]CXu3w(J
VTE .^EK!
privatestaticboolean hasPrePage(int currentPage){ ;e *!S}C,
return currentPage == 1 ? false : true; 7!E,V:bt'
} } q8ASYNc
zrb}_
privatestaticboolean hasNextPage(int currentPage, B]tQ(s~
O\r0bUPE
int totalPage){ {P_.~0pc*
return currentPage == totalPage || totalPage == 6i/(5 nQ
.ioEIs g
0 ? false : true; xy;;zOh`
} \4fQMG
.Q2V}D85
rey!{3U
} =aW9L)8D
%.|@]!C
Km$\:Xo
9%9#_?RW
bk[!8-b/a
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 R6->t #n,
zO6oT1I
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 \9T7A&
P*j|.63
做法如下: 3Y$GsN4ln
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 #H~64/
~t~|"u"P
的信息,和一个结果集List: ;2QP7PrSY
java代码: |A(Iti{v
tCt#%7J;a
+ZP7{%
/*Created on 2005-6-13*/ p`qgrI`
package com.adt.bo; ?:0Jav
Mo|2}nf
import java.util.List; (E1~H0^
>m\(6x8RE
import org.flyware.util.page.Page; m8[j #=h
v]UwJz3<
/** /)O"l @ }U
* @author Joa ~k5W@`"W
*/ JxU5 fe
publicclass Result { Q7CsJzk~)
;O,jUiQ
private Page page; &rR2,3r=
N;%6:I./
private List content; F#E3q|Q"BS
@=u3ZVD
/** JucY[`|JV
* The default constructor jL}v9$
*/ OY({.uV dX
public Result(){ hDGF7
super(); >H,*H;6
} owv[M6lbD
^-'fW7[m
/** _yR^*}xJb
* The constructor using fields e*1_ 8I#2
* R4d=S4i
* @param page a 1*p*dM#
* @param content S+lqA-:
*/ "0TZTa1e
public Result(Page page, List content){ 47/iF97
this.page = page; tZo} ;|~'
this.content = content; '|=;^Z7.K
} zm;C\s rF
GC'O[q+
/** 2Tppcj v
* @return Returns the content. [2cD:JL
*/ FpU>^'2]
publicList getContent(){ d #wVLmKZ
return content; dAj$1Ke
} ]]yO1x$Kk
I%Z
/** 3Zh)]^
* @return Returns the page. lu/
(4ED
*/ BJ(M2|VH
public Page getPage(){ OZ;*JR:
return page; =2x^nW
} 7 X4LJf
2:ylv<\$
/** \73ch
* @param content apxph2yvS
* The content to set. u]@['7
*/ tq?!-x+>
public void setContent(List content){ TL#3;l^
this.content = content; +"VP-s0
} )`D:F>p*
2J;g{95z
/** v &+R^iLE
* @param page bZV/l4TU
* The page to set. #.[k=dj
*/ >LuYHr
publicvoid setPage(Page page){ #_ lDss
this.page = page; teVM*-
} 4KrL{Z+}
} dgePPhj
T[A69O]v
Ga'swP=hf
WX0tgXl
?z
u8)U
2. 编写业务逻辑接口,并实现它(UserManager, ig &Y
"zy7C*)>r
UserManagerImpl) I<tm"?q0
java代码: 8\gjST*
v.5+7,4
)dSi/
/*Created on 2005-7-15*/ 4X|zmr:A
package com.adt.service; SX-iAS[<
T]p-0?=4vv
import net.sf.hibernate.HibernateException; uW3!Yg@
pD+k*
import org.flyware.util.page.Page; OZ!^ak
L8 @1THY
import com.adt.bo.Result; 3f;>" P}
S21,VpW\
/** t0?\l)
* @author Joa POR\e|hRT]
*/ L j$;:/G
publicinterface UserManager { \nqS+on]
0qT%!ku&
public Result listUser(Page page)throws ?G&ikxl
c[Zje7 @
HibernateException; Z EO WO
^G-@06 /!
} dC4'{n|7
4xJQ!>6
>yh2Lri
&iVs0R
\D&KC,i5f
java代码: /H+a0`/
7v_8_K
BFW&2
/*Created on 2005-7-15*/ GvlS%
package com.adt.service.impl; OK
gqT!
76` .Y
import java.util.List; ,,|^%Ct']
ei5~&
import net.sf.hibernate.HibernateException; n?K
^/=KK:n~
import org.flyware.util.page.Page; k-""_WJ~^
import org.flyware.util.page.PageUtil; 7j)8Djzp|
W`*r>`krVJ
import com.adt.bo.Result; /5AJ.r
import com.adt.dao.UserDAO; lB[kbJ
import com.adt.exception.ObjectNotFoundException; s(roJbJ_;
import com.adt.service.UserManager; S`?!G&[!>
9Lfv^V0
/** v74&BL]a
* @author Joa 0Fr?^3h
*/ Oz#{S:24M+
publicclass UserManagerImpl implements UserManager { d*Fj3Wkx
G<;*SYAb
private UserDAO userDAO; c_l"I9M#r
9JKEw
/** k.15CA`
* @param userDAO The userDAO to set. #yvGK:F
*/ eQvg7aO;
publicvoid setUserDAO(UserDAO userDAO){ -o
EW:~y
this.userDAO = userDAO; ?@
$r
} e64 ^ChCoV
Lq!>kT<]!
/* (non-Javadoc) ;P&OX5~V
* @see com.adt.service.UserManager#listUser N$:8,9.z
w"&n?L
(org.flyware.util.page.Page) eGbGw
*/ @gXx1hEg
public Result listUser(Page page)throws b*Q&CL
r-/`"j{O!
HibernateException, ObjectNotFoundException { 5.J.RE"M
int totalRecords = userDAO.getUserCount(); ]:/Q]n^
if(totalRecords == 0) mUx+Y ]Ep
throw new ObjectNotFoundException 63x?MY6
t5IEQ2
("userNotExist"); yJe>JK~)
page = PageUtil.createPage(page, totalRecords); u08mqEa
List users = userDAO.getUserByPage(page); qA5r
returnnew Result(page, users); t.\dpBq
} K)k<Rh[<
=zs`#-^8
} t9IW/Q
57'4ljvYi
U_c *6CK
DkAAV9*
yyy|Pw4:Z
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 I[X772K
&~U ] ~;@
询,接下来编写UserDAO的代码: B@
KQ]4-
3. UserDAO 和 UserDAOImpl: ('p5:d
java代码: P J[`|
R0
K@w{"7}
/*Created on 2005-7-15*/ {3vNPQJ
package com.adt.dao; fL7xq$K
0% I=d
import java.util.List; @>H75
,UdVNA
import org.flyware.util.page.Page; WQO) =n
G9<X_
import net.sf.hibernate.HibernateException; 4)o
h;NYdX5
/** @bP)406p
* @author Joa i,9)\1R
*/ 7EO_5/cY
publicinterface UserDAO extends BaseDAO { cq4Ipe
>Wg hn:^
publicList getUserByName(String name)throws
ls)%c
{h`uV/5@`
HibernateException; >`ZyG5
| (_
publicint getUserCount()throws HibernateException; HT1!5
A1zjPG&]
publicList getUserByPage(Page page)throws Bo%NFB;
L5:$U>H(
HibernateException; Alw3\_X
%z4Nl$\
}
c=.(!qdH
l0A&9g*l2
QGmn#]w\\
SS.dY""89
UFb)AnK
java代码: /FEVmH?
L8#5*8W6
!f&g-V
/*Created on 2005-7-15*/ @/-\k*T
package com.adt.dao.impl; G{%L B}2
fNZ__gO!%
import java.util.List; t |A-9^t'!
(0y~%J
import org.flyware.util.page.Page; WlBc.kFck
R`^_(yn>
import net.sf.hibernate.HibernateException; hSyql
import net.sf.hibernate.Query; #],&>n7'
{o`]I>gb
import com.adt.dao.UserDAO; d <JM36j?
:1KpGj*F
/** (,Df^4%7
* @author Joa ]yPqLJ
*/ ZoZ|Ma
public class UserDAOImpl extends BaseDAOHibernateImpl 8X)Y^uGGZ
9o:Lz5o
implements UserDAO { $43qME
&m:uO^-D
/* (non-Javadoc) /{--+
C
* @see com.adt.dao.UserDAO#getUserByName I,@6J(9
>>fH{/l
(java.lang.String) .gOL1`b*
*/ hv_XP,1K
publicList getUserByName(String name)throws aM0f/"-_
+@iA;2&
HibernateException { ]^K4i)\
String querySentence = "FROM user in class >%8KK|V{
_D(rI#q
com.adt.po.User WHERE user.name=:name"; 2u*KM`fa`
Query query = getSession().createQuery LvUj9eVb/L
rFYWs6
(querySentence); _&ks1cw
query.setParameter("name", name); "y/?WQ>,3
return query.list(); *w0%d1
} Jcm&RI"{
JQHvz9Yg
/* (non-Javadoc) tc{sB\&-
* @see com.adt.dao.UserDAO#getUserCount() !6Mo]xh
*/ O2dW6bt
publicint getUserCount()throws HibernateException { )*x6 FfTUd
int count = 0; u-G+ j)
String querySentence = "SELECT count(*) FROM bTs?!~q
;
_1
at
user in class com.adt.po.User"; \<TXS)w]
Query query = getSession().createQuery G..aiA
0o*8#i/)!3
(querySentence); Oh6fj}eK
count = ((Integer)query.iterate().next !lc[
+<3XJ7D
()).intValue(); e@*
EzvO
return count; !6>~?gNd
} VYImI>.t{
Ob`d
/* (non-Javadoc) !AfHk|
* @see com.adt.dao.UserDAO#getUserByPage @;?p&.W`D
q0r>2c-d
(org.flyware.util.page.Page) |kV*Jc k
*/ $Kncvu
publicList getUserByPage(Page page)throws Zu("#cA.H
xx9 g''Q
HibernateException { $#pPZ
String querySentence = "FROM user in class KRMQtgahc
[o+q>|q
com.adt.po.User"; y0.8A-2:
Query query = getSession().createQuery .Cl:eu,]
!1{e|p
7
(querySentence); q0R -7O(
query.setFirstResult(page.getBeginIndex()) ,a]?S^:y]
.setMaxResults(page.getEveryPage()); NDlF0f
return query.list(); kw%};;
} "PTZ%7YH}
l@+7:n4K0
} 27O|).yKX
@H7d_S
F{~{Lthc
,UGRrS
%r}{hq4
至此,一个完整的分页程序完成。前台的只需要调用 bITPQ7+
KZ
;k)O.Ov
userManager.listUser(page)即可得到一个Page对象和结果集对象 :AF =<X*5
;=;
9tX
的综合体,而传入的参数page对象则可以由前台传入,如果用 {rH@gz|@i
:L RYYw
webwork,甚至可以直接在配置文件中指定。 SVs_dG$
6NM:DI\%
下面给出一个webwork调用示例: !y:vLB#q
java代码: ^2on.N q>
vZ&T}H~8
iwp{%FF
/*Created on 2005-6-17*/ CpeU5 o@
package com.adt.action.user; 4NzwE(
-$jEfi4I
import java.util.List; W~~7C,!
;HJLs2bP
import org.apache.commons.logging.Log; W=Mb
import org.apache.commons.logging.LogFactory; v)l8@.
import org.flyware.util.page.Page; 9-
YwkK#z
MmnOHN@.
import com.adt.bo.Result; J|kR5'?x
import com.adt.service.UserService; ()Y4v
import com.opensymphony.xwork.Action; TKY*`?ct
,t9^j3Ixg
/** y 4I6
* @author Joa :'3XAntZA
*/ X=!^] 3zH
publicclass ListUser implementsAction{ G{ sOR
^*8G8'k;$
privatestaticfinal Log logger = LogFactory.getLog 4C-jlm)V
3z)Kz*xr
(ListUser.class); UA8GL D9
3U.88{y
private UserService userService; &U
raUl
oe
|)oTv
private Page page; =2zJ3&9
hp*/#D
privateList users; E.ly#2?
ceM6{N<_U
/* |_*O '#jx
* (non-Javadoc) TYmP)
* %Yicg6:
* @see com.opensymphony.xwork.Action#execute() CBOi`bEf
*/ ;8*`{F[
publicString execute()throwsException{ 9XyYHi
Result result = userService.listUser(page); P'*)\faw
page = result.getPage(); 9S7kUl{
users = result.getContent(); 5rRN-
return SUCCESS; h[1MtmNw
} X;B\Kj`n
[t7]{d*
/** i2YuOV!
* @return Returns the page. Q}K#'Og
*/ 7X q,z
public Page getPage(){ #Jn_c0
return page; ?ROqn6k&c
} RwPN gRF
&8>IeK{I
/** )XakJU^o
* @return Returns the users. U.XNv-M
*/ gb> }v7
publicList getUsers(){ fX.>9H[w@~
return users; 4%}*&nsI-Z
}
HA`@7I
`V"sOTb
/** SWQ5fcPu
* @param page tqeZ#w7
* The page to set. aj}sc/Qa
*/ VUYmz)m5
publicvoid setPage(Page page){ Q7$.LEioN
this.page = page; AvSM^
} .J.-Mm`.
I1\a[Xe8E
/** T ;vF(
* @param users GXjfQ~<]
* The users to set. C;`XlQG `
*/ {R61cD,n
publicvoid setUsers(List users){ ?jt}*q>X]
this.users = users; &A)B~"[~
} Tp?y8r
)h|gwERj
/** {]_r W/
* @param userService N:tY":Hi
* The userService to set. X
9%'|(tL
*/ ;D
s46M-s
publicvoid setUserService(UserService userService){ x{,q]u /
this.userService = userService; ,0~9dS
} :l&V]}:7*
} ^#1.l=s
?(m
jx
vR=6pl$|~~
AfP'EP0m
9D}/\jM
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, DUe&r,(4O
E)7F\ w
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 S:q3QgU=X
.G(llA}
么只需要: f0<%&2ym
java代码: ]oV{t<0a
QgD g}\P
P=+nB*hG
<?xml version="1.0"?> )aao[_ZS
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork VX+jadYdq
MJCzo |w
1.0//EN" "http://www.opensymphony.com/xwork/xwork- hL;8pE8
!F4@KAv
1.0.dtd"> 6"t;gSt4
,H2D
<xwork> f{i8w!O"~
UH>F|3"d
<package name="user" extends="webwork- a/U2xq{x
PN<C=gAe
interceptors"> bb`':3%
P<2+L|X?}
<!-- The default interceptor stack name |vMpXiMxxT
saAxGG
--> 4)4+M
<default-interceptor-ref @]c(V%x
hj$e|arB
name="myDefaultWebStack"/> 8kOKwEX
N0w`!<y:c
<action name="listUser" ?@t d
#D9e$E(J^
class="com.adt.action.user.ListUser"> 2gjGeM
<param zrv#Xa!O\
rVa?JvDO=
name="page.everyPage">10</param>
|?,[@z _,
<result 7`H
1f]d
6^n0[7
name="success">/user/user_list.jsp</result> k@D0 {z
</action> I3:[= ,5
(?kl$~&|
</package> <zy,5IlD
}Jh: 8BNuP
</xwork> Xy5s^82?
7HJS.047
9F-
)r'
'snn~{hG
5,;`$'?a%
/?6|&
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 J5[~LZKW
r-IVb&uFb
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。 deeU@x`f<
?Xo*1Z =
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 70Yjv1i
c$,_>tcP
Lru-u:
BH@)QVs-
cx$Gic:4
我写的一个用于分页的类,用了泛型了,hoho 1b>C<\
#4h+j%y[H
java代码: p|/j4@-h
NHgjRPz"
n*'<uKpM
package com.intokr.util; Grz 3{U
0 Hw-59MK
import java.util.List; xf>z @)e
|nk3^;Yf
/** l\!-2 T6Y
* 用于分页的类<br> ]G}B 0u3
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 's!-80sd
* ExXM:1 e26
* @version 0.01 _uu<4c
* @author cheng cj|*_}
*/ u%d K ig
public class Paginator<E> { $7Mtt.d6
privateint count = 0; // 总记录数 HFQR
;9]
privateint p = 1; // 页编号 rJ'I>Q~x6
privateint num = 20; // 每页的记录数 o:dR5v
privateList<E> results = null; // 结果 i=32KI(%
V'2EPYB
/** +1Ph<zq"
* 结果总数 Lx U={Y0
*/ 5[9bWB{
publicint getCount(){ X#UMIlU
return count; wj|x:YZ*
} >7U>Yh
j#6|V]l
publicvoid setCount(int count){ iG,t_??
this.count = count; -
?!:{UXl
} $O:w(U
Vjm_F!S
/** M}"r#Plq
* 本结果所在的页码,从1开始 yISD/
g
* w*w?S
* @return Returns the pageNo. E}Xka1 Bn
*/ N(3R|Ii
publicint getP(){ W {.78Zi9K
return p; I5);jgb
} FkupO
[KI
AdoZs8Q
/** ;}.Kb
* if(p<=0) p=1 {sv{847V
* rp:wQH7
* @param p o8FXqTUcs4
*/ q cA`)j
publicvoid setP(int p){ qturd7
if(p <= 0) Y
ZaP
p = 1; 7/X"z=Q^|
this.p = p; Zq ot{s
} N\1/JW+
I]J*BD#n.
/** /=#~
* 每页记录数量 !m{2WW-
*/ 9-bG<`v\E
publicint getNum(){ H.O(*Q=
return num; zy N (4
} EZ(^~k=I
g"!\\:M
/** -lRhz!E]
* if(num<1) num=1 r7!J&8;{K
*/ YirC*
publicvoid setNum(int num){ eE/%6g
if(num < 1) {rkn q_;0
num = 1; azb=(l-
this.num = num; oBlzHBn>0
} 8!h'j
._p""'Sa
/** \w)?SVp
* 获得总页数 76#.F
*/ *"G 8
publicint getPageNum(){ N^elVu4 K
return(count - 1) / num + 1; ^4`&EF
} _&
4its
t&814Uf&\
/** D)&o8D`
* 获得本页的开始编号,为 (p-1)*num+1 f@:CyB GQ
*/ j[S`^2
publicint getStart(){ 0B0G2t&hr
return(p - 1) * num + 1; IB7tAG8
} T }uE0Z,
]u&dJL
/** ,bSVVT-b
* @return Returns the results. O5 7jz= r
*/ %7`d/dgR
publicList<E> getResults(){ j=.g:&r)
return results; )hL^+Nn bR
} !J.rM5K
d0C8*ifFO
public void setResults(List<E> results){
'=TTa
this.results = results; 9Nl*4
} U
%:c],Fk
S[@6Lp3q_
public String toString(){ 9 |K*G~J
StringBuilder buff = new StringBuilder ':;LrTc'K
Ww87
(); q?VVYZXP
buff.append("{"); B {i&~k
buff.append("count:").append(count); Tj,Nmb>Q7'
buff.append(",p:").append(p); g+Ph6W
buff.append(",nump:").append(num); h1%y:[_
buff.append(",results:").append ?\yB)Nd y
\!X?zR_
(results); j3P RAe
buff.append("}"); L/k40cEI^z
return buff.toString(); WX*cI Cb5
} mvf
_@2^
hrlCKL&
} O~Uw&Bq
1XnBK$`
nJ# XVlHc