Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 m,5?|J=
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &
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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 L@?3E`4/v
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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 ^ME'D
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。 q}z`Z/`/
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分页支持类: <<Z, 1{3F
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java代码: :N_DJ51
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package com.javaeye.common.util; |v1*
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import java.util.List; BJg
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publicclass PaginationSupport { aej'c bO
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publicfinalstaticint PAGESIZE = 30; b9v<Jk
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privateint pageSize = PAGESIZE; xm=$D6O:
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privateList items; fILvEf4b
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privateint totalCount; -]n%+,3L
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privateint[] indexes = newint[0]; M7&G9SGZ
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privateint startIndex = 0; EP+LK?{%
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public PaginationSupport(List items, int sN#ju5
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totalCount){ dB:c2
setPageSize(PAGESIZE); 47f\
setTotalCount(totalCount); q)AX*T+
setItems(items); cF?0=un
setStartIndex(0); Qam48XZ >
} +m/n~-6q
}WBHuVcZG
public PaginationSupport(List items, int U;!J(Us
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totalCount, int startIndex){ }u{gQlV
setPageSize(PAGESIZE); lXzm)
setTotalCount(totalCount); =+q\Jh
setItems(items); 4:/^ .:
setStartIndex(startIndex); l/\D0\x2
} XGjFb4Tw7
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public PaginationSupport(List items, int ~03MH'
M* {5> !\
totalCount, int pageSize, int startIndex){ k_Y7<z0G
setPageSize(pageSize); Q(e
setTotalCount(totalCount); YBF$/W+=9|
setItems(items); xH}bX- m
setStartIndex(startIndex); WJ[>p
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} }Gy M<!:
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publicList getItems(){ (XY`1|])`
return items; D_)/.m
} Xkg
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publicvoid setItems(List items){ )}t't"
this.items = items; m4Ue)
} ;K%/sIIke
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publicint getPageSize(){ TU*EtE'g/
return pageSize; "^a"`?J
} KC9e{
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publicvoid setPageSize(int pageSize){ .aVt d
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this.pageSize = pageSize; ItZYOt|Hn
} Jyr
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publicint getTotalCount(){ o
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return totalCount; Kr `/sWZ
} het<#3Bo
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publicvoid setTotalCount(int totalCount){ a7453s
if(totalCount > 0){ ^w2 HF
this.totalCount = totalCount; r\Kcg~D>
int count = totalCount / Ym!e}`A\F
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pageSize; (Cfb8\~
if(totalCount % pageSize > 0) tMp!MQ
count++; 5b*knN>
indexes = newint[count]; 8N?D1;F;
for(int i = 0; i < count; i++){ h:r?:C>n
indexes = pageSize * CH
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i; o[fg:/5)A
} Ke?,AWfG
}else{ d!YP{y P
this.totalCount = 0; Y?3tf0t/
} Hq 3V+$
} Lhe&
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publicint[] getIndexes(){ 6$'*MpYF4
return indexes; ?+^p$'5
} <r$h =hM
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publicvoid setIndexes(int[] indexes){ (;%T]?<9#
this.indexes = indexes; /lu|FWbEw
} VJ&<6
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publicint getStartIndex(){ }$'_%,
return startIndex; j-W$)c3X
} |D"L!+J-$
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publicvoid setStartIndex(int startIndex){ 3IlVSR^py
if(totalCount <= 0) NR1M W^R
this.startIndex = 0; c {%mi
elseif(startIndex >= totalCount) H@?} !@
this.startIndex = indexes XGH:'^o_
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[indexes.length - 1]; )&d=2M;3
elseif(startIndex < 0) 1BU97!
this.startIndex = 0; j2UQQFh
else{ ng!cK<p
this.startIndex = indexes MyllL@kP
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[startIndex / pageSize]; x]x 3iFD
} pTwzVz~
} L%is"NZh
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publicint getNextIndex(){ 6{=U=
*
int nextIndex = getStartIndex() + 4A6Y
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pageSize; xw
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if(nextIndex >= totalCount) \2 N;VE
return getStartIndex(); EHm*~Sd
else eTvjo(Lvx
return nextIndex; (4/"uj5
}
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publicint getPreviousIndex(){ nLz;L r!
int previousIndex = getStartIndex() - klT?h[I!
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pageSize; t8EI"|
if(previousIndex < 0) )__sw
return0; )-&@8`
else @M4c/k}
return previousIndex; @i>)x*I#AI
} }
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} ue@/o,C>
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抽象业务类 AYfOETz
java代码: %QEBY>|lI
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/** k4LrUd
* Created on 2005-7-12 `~)?OTzU#
*/ #RR;?`,L}
package com.javaeye.common.business; it\$Pih]
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import java.io.Serializable; ~Yk^(hl2
import java.util.List; 3Jizv,?
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import org.hibernate.Criteria; auK9wQ%\
import org.hibernate.HibernateException; q@bye4Ry%W
import org.hibernate.Session; :k1?I'q%
import org.hibernate.criterion.DetachedCriteria; O^8ZnN_+
import org.hibernate.criterion.Projections; T"vf
import Ip{R'HG/
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org.springframework.orm.hibernate3.HibernateCallback; #Pg`0xiV
import g,JfT^
3=uhy|f! /
org.springframework.orm.hibernate3.support.HibernateDaoS qo3+=*"V
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upport; P".}Y[GD
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import com.javaeye.common.util.PaginationSupport; yk?bz
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public abstract class AbstractManager extends n/1t UF
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HibernateDaoSupport { qK.(wFx
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privateboolean cacheQueries = false; i0{\c}r:4b
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privateString queryCacheRegion; .?6p~
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publicvoid setCacheQueries(boolean R*:$^v@4
no<$=(11i
cacheQueries){ NRtH?&7
this.cacheQueries = cacheQueries; r=n{3o+
} 17KQ
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publicvoid setQueryCacheRegion(String 3XQa%|N(
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queryCacheRegion){ Vt}QPNt
this.queryCacheRegion = @h|qL-:!vG
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queryCacheRegion; }X{rE|@
} %J-0%-/_S:
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publicvoid save(finalObject entity){ >M2~p&Si
getHibernateTemplate().save(entity); !}h)
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} >S:(BJMo
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publicvoid persist(finalObject entity){ *`+zf7-f
getHibernateTemplate().save(entity); EX_j|/&tZ
} LMoZI0)x
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publicvoid update(finalObject entity){ 7!AyL w
getHibernateTemplate().update(entity); Y
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} [M[#f&=Z
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publicvoid delete(finalObject entity){ 6ncwa<q5
getHibernateTemplate().delete(entity); GL O3v.
n;
} -b^dK)wR~
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publicObject load(finalClass entity, e}?Q&Lci
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finalSerializable id){ Qg/FFn^Kg*
return getHibernateTemplate().load l0,VN,$Yl
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(entity, id); UnK7&Uo
} a4ViVy
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publicObject get(finalClass entity, h_ 4*?w
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finalSerializable id){ q3#[6!
return getHibernateTemplate().get nvndgeSy
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(entity, id); .hx(9
} E\/[hT
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publicList findAll(finalClass entity){ rB".!b
return getHibernateTemplate().find("from 1+*sEIC "
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" + entity.getName()); lW|=rq-|
} m)L50ot:/
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publicList findByNamedQuery(finalString q~9-A+n
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namedQuery){ 5vLXMdN
return getHibernateTemplate '/xynk%)xw
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().findByNamedQuery(namedQuery); m'}`+#C%)
} m:)&:Y0 (a
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publicList findByNamedQuery(finalString query, Q8`V0E\~
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finalObject parameter){ F 6sQeU
return getHibernateTemplate y\_+,G0
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().findByNamedQuery(query, parameter); 1?&|V1vc
} eXKEx4rU
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publicList findByNamedQuery(finalString query, SN@>m pcJS
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finalObject[] parameters){ 1J9p1_d5
return getHibernateTemplate }=EJM7sM|k
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().findByNamedQuery(query, parameters); d\>XfS
} -&
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publicList find(finalString query){ e;XRH<LhAU
return getHibernateTemplate().find m
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(query); } +Sp7F1q
} Zy7kPL;b
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publicList find(finalString query, finalObject hiVa\s
({rcH.:
parameter){ ]^"Lc~w8&
return getHibernateTemplate().find }Ecv6&G
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(query, parameter); h.K"v5I*
} Ew0)MZ.#
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public PaginationSupport findPageByCriteria V7U*09
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(final DetachedCriteria detachedCriteria){ IoOOS5a
return findPageByCriteria |v7Je?yh
Pi"?l[T0
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 8lx}0U
} 6V$ )ym*F
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public PaginationSupport findPageByCriteria 1,=:an
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(final DetachedCriteria detachedCriteria, finalint 8F>9CO:&N
?{ '_4n3O
startIndex){ T`@brL
return findPageByCriteria X% 05[N
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(detachedCriteria, PaginationSupport.PAGESIZE, Kkq-x'gt^
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startIndex); Xd A]);,
} @cIYS%iZ
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public PaginationSupport findPageByCriteria ?<4pYEP
b * \
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(final DetachedCriteria detachedCriteria, finalint 2fkyz
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pageSize, gnZ#86sO
finalint startIndex){ J=Kv-@I>E
return(PaginationSupport) Mw,]Pt6~i
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getHibernateTemplate().execute(new HibernateCallback(){ pBe1:
publicObject doInHibernate ]d(Z%
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(Session session)throws HibernateException { 95IP_1}?
Criteria criteria = N<SW
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detachedCriteria.getExecutableCriteria(session); {wM<i
int totalCount = XE_Lz2H`
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((Integer) criteria.setProjection(Projections.rowCount yg8= G vO
}JtcAuQt
()).uniqueResult()).intValue(); Z{vc6oj
criteria.setProjection u:J(0re
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(null); JZ`u?ZaJ/s
List items = l@SV!keQ
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criteria.setFirstResult(startIndex).setMaxResults "gNi}dB<]
O9N!SQs80
(pageSize).list(); 'eBD/w5U
PaginationSupport ps = ~roNe|P
)0E_Y@
new PaginationSupport(items, totalCount, pageSize, '%/=\Q`
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startIndex); AVLY|79#
return ps; >|RoLV
} "Ai\NC
}, true); &V
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} Y>3zpeQ!&
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public List findAllByCriteria(final 6I(Y<LZ5
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DetachedCriteria detachedCriteria){ >!Y#2]@}o
return(List) getHibernateTemplate =LIb0TZ2
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().execute(new HibernateCallback(){ 4_>;|2
publicObject doInHibernate %cDGs^lgA
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(Session session)throws HibernateException { I-8I/RRkmP
Criteria criteria = #*9 |\
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detachedCriteria.getExecutableCriteria(session); ?4 wl
return criteria.list(); `0%;Gz%}
} 7./WS,49
}, true); I/upiq y
} aC' 6
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public int getCountByCriteria(final bHm/Z Zx
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DetachedCriteria detachedCriteria){ 13 L&f\b
Integer count = (Integer) -wH0g^Ed
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getHibernateTemplate().execute(new HibernateCallback(){ E4\HI+
publicObject doInHibernate lGK7XAx,
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(Session session)throws HibernateException { z7BFkZ6+
Criteria criteria = C8v
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detachedCriteria.getExecutableCriteria(session); *GYLj[
return "D>/#cY1/
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criteria.setProjection(Projections.rowCount dm"x?[2:
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()).uniqueResult(); r2tE!gMC
} j0oto6z~b
}, true); /C'_-U?
return count.intValue(); cV1E<CM
} 2s,cyCw&
} e/x 9@1s#
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用户在web层构造查询条件detachedCriteria,和可选的 $s
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4W2.K0Ca
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PaginationSupport的实例ps。 ?Qd`Vlp7
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ps.getItems()得到已分页好的结果集 !S7?:MJ?p\
ps.getIndexes()得到分页索引的数组 Z$c&Y>@)
ps.getTotalCount()得到总结果数 /g%RIzgW
ps.getStartIndex()当前分页索引 _7u&.l<;
ps.getNextIndex()下一页索引 qmPu D/c
ps.getPreviousIndex()上一页索引 )gU:Up24|"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 I4ZbMnO
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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 ;D-k\kv
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一下代码重构了。 hxJKYU^%m
n]3'N58
我把原本我的做法也提供出来供大家讨论吧: Q$:,N=%
.#sX|c=W
首先,为了实现分页查询,我封装了一个Page类: GHLFn~z@XJ
java代码: sAA;d
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/*Created on 2005-4-14*/ t]vv&vk>
package org.flyware.util.page; o*d (;
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/** =d~pr:.F
* @author Joa ub1~+T'O
* MUtM^uY
*/ <WmjjD
publicclass Page { .MDSP/s
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/** imply if the page has previous page */ Zs0;92WL
privateboolean hasPrePage; pwSkw J]
{#@[ttw$U
/** imply if the page has next page */ ~z41$~/
privateboolean hasNextPage; &{wRB l #
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/** the number of every page */ Y>E` 7n
privateint everyPage; zcOm"-E-
^I6Vz?0Jl
/** the total page number */ c9nv=?/}f
privateint totalPage; )FA:wsy~E
FW3E UC)P
/** the number of current page */ Xfb-<
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privateint currentPage; i8cmT+}>
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/** the begin index of the records by the current e<A>??h^
}43qpJe8U
query */ vz:VegS
privateint beginIndex; (VC Jn<@@
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/** The default constructor */ ^* y1Fn0
public Page(){ 48;b
c\szy&W
} RMs8aZCa
KdTWi;mV2-
/** construct the page by everyPage l]R7A_|
* @param everyPage !xg10N}I
* */ wLfH/J
public Page(int everyPage){ *[jq&
this.everyPage = everyPage; nD
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} |XQ\c.A
DV({! [EP
/** The whole constructor */ `4Z:qh+fJ
public Page(boolean hasPrePage, boolean hasNextPage, NVom6K
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y
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int everyPage, int totalPage, 5YI6$ZdQ
int currentPage, int beginIndex){ L"T :#>
this.hasPrePage = hasPrePage; &(o&Y
this.hasNextPage = hasNextPage; #'i,'h+F
this.everyPage = everyPage; ofYZ!-V
this.totalPage = totalPage; h y\iot
this.currentPage = currentPage; ]gA2.,)}D
this.beginIndex = beginIndex; #c/K.?
} BOdlz#&s
WkpHe
/** )#? K2E
* @return /
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* Returns the beginIndex. p]s)Xys
*/ ]}&HvrOld
publicint getBeginIndex(){ ^H&`e"|R9
return beginIndex; #?>pl.
} cnY}^_
CqX*.j{
/** m("KLp8
* @param beginIndex 9*!*n ~
* The beginIndex to set. 5lwMc0{/3
*/ 7~N4~KAUS
publicvoid setBeginIndex(int beginIndex){ "r@G V5ED
this.beginIndex = beginIndex; $RC)e7
} elD|b=(-
c4Q%MRR
/** X
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* @return FId,/la
* Returns the currentPage. NJ$Qm.S
*/ f&Sovuuh
publicint getCurrentPage(){ -0k{O@l"
return currentPage; 4z OFu/l6R
} UQb|J9HY4
:8v? 6Q
/** 4 4WyfpTJ*
* @param currentPage NUtKT~V
* The currentPage to set. O2lM;="
*/ \ZSq ZDq
publicvoid setCurrentPage(int currentPage){ :"i2`y;u
this.currentPage = currentPage; ( pCU:'"
} ^7:UC\_
B'PS-Jr
/** T#H-GOY:
* @return ^%U`|GBZp
* Returns the everyPage. +t]Ge
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*/ au+:-Khm
publicint getEveryPage(){ Psf{~ (Ii
return everyPage; e?GzvM'2
} ^>fr+3a"P
x%dVD
/** eQfXUpk3@I
* @param everyPage T&<ee|t@{
* The everyPage to set. y"_rDj`
*/ O^3XhTW^\~
publicvoid setEveryPage(int everyPage){ aOUTKyR ~
this.everyPage = everyPage; *iSE)[W
} $>wN:uN(
+
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/** '+GYw$
* @return #~r+Z[(,p
* Returns the hasNextPage. F}B2nL&
*/ {XnBj}C
publicboolean getHasNextPage(){ *oh,Va
return hasNextPage; dL1{i,M
} L5wFbc"u
\~C/
/** Ga
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* @param hasNextPage ;hd%wmE
* The hasNextPage to set. +.u
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*/ \5HVX/
publicvoid setHasNextPage(boolean hasNextPage){ (;N#Gqb6l
this.hasNextPage = hasNextPage; T.WN9=N
} \MAv's4b@
{Q^ -
/** 83)m#
* @return $?OQtz@
* Returns the hasPrePage. #zb6 7mg~
*/ [E9_ZdBT
publicboolean getHasPrePage(){ cNy*< Tv
return hasPrePage; W$gjcsv
} (|tR>R.Wxg
sv!6zJs
/** [| C
* @param hasPrePage zgxMDLH
* The hasPrePage to set. E7<l^/<2S+
*/ Ud#xgs'
publicvoid setHasPrePage(boolean hasPrePage){ 1b2xWzpG
this.hasPrePage = hasPrePage;
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} ^>y|{;`
~KxK+6[ :
/** 9G[t
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* @return Returns the totalPage. ;_/!F}d
* WjvgDNk
*/ 6x16?x
publicint getTotalPage(){ P
qa;fiJ)
return totalPage; Rf{YASPIw&
} q9Lq+4\
V#~.n;d
/** &i*e&{L7
* @param totalPage B\~(:(OPM]
* The totalPage to set. #Xi9O.
*/ 0"mr*hyj
publicvoid setTotalPage(int totalPage){ ]];LA!n
this.totalPage = totalPage; IKp/xj[!
} mU>lm7'
]C-a[
} \.=,}sV2Z
tSTl#xy
8`|Z9umW*
/!hxW}>^
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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 f!B\X*|
[QwqP=-6
个PageUtil,负责对Page对象进行构造: V$ "]f6
java代码: UrdSo"%
ERfSJ
-Y>QKS
/*Created on 2005-4-14*/ 'lgS;ItpKu
package org.flyware.util.page; #*"I?B/fd8
8HWEObRY
import org.apache.commons.logging.Log; K/!>[d
import org.apache.commons.logging.LogFactory; 2:1
kSR^Ky
A-u}&}l<
/** 8?hj}}H
* @author Joa $N4i)>&T2
* cM=_i{c
*/ M1K[6V!
publicclass PageUtil { 4B-+DH>{6
Fw%S%*B8g
privatestaticfinal Log logger = LogFactory.getLog e#ne 5
1@q"rPE^
(PageUtil.class); }Gd^r
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/** [4mIww%
* Use the origin page to create a new page Ro#O{
* @param page LUA<N:
* @param totalRecords A/~^4DR
* @return oK2j PP
*/ J+qcA}
publicstatic Page createPage(Page page, int z+j3j2
Htce<H-P
totalRecords){ lh;;%@1DM
return createPage(page.getEveryPage(), n7bML?f'
"]yfx@)_
page.getCurrentPage(), totalRecords); IG4`f~k^
} (usPAslr
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/** ({hW
* the basic page utils not including exception Ka8Bed3
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handler &hIr@Gi@ch
* @param everyPage -8sB\E
* @param currentPage gzp]hh@4
* @param totalRecords GAlM:>
* @return page @[O|n)7
*/ P2
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publicstatic Page createPage(int everyPage, int [:l=>yJ{(
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currentPage, int totalRecords){ 2Jt*s$
everyPage = getEveryPage(everyPage); F2',3
currentPage = getCurrentPage(currentPage); %5<Xa
int beginIndex = getBeginIndex(everyPage, y+M9{[ i/O
@zig{b 8
currentPage); >8gb/?z
int totalPage = getTotalPage(everyPage, Q\z9\mMG-
F?4&qbdD
totalRecords); gnw?Y 2
boolean hasNextPage = hasNextPage(currentPage, "lKR~Qi
f<Yg_ TG
totalPage); wU&vkb)k
boolean hasPrePage = hasPrePage(currentPage); Gi,4PD-ro
DxG8`}+
returnnew Page(hasPrePage, hasNextPage, Y".4."NX
everyPage, totalPage, :a)` iJnb
currentPage, W9jxw4)
rf
=Wq_
beginIndex); !4T7@V`G
} N?c!uO|h|
+LaR_n[
privatestaticint getEveryPage(int everyPage){ }i9VV+L#1
return everyPage == 0 ? 10 : everyPage; G]gc*\4
} 5:SS2>~g
}%S#d&wh$_
privatestaticint getCurrentPage(int currentPage){ w!52DBOe+
return currentPage == 0 ? 1 : currentPage; ZY8:7Q@P>
} o=C'u
4u7^v1/
privatestaticint getBeginIndex(int everyPage, int h:<?)g~U
'A'[N :i
currentPage){ ZP"Xn/L
return(currentPage - 1) * everyPage; Z (C0+A\
} bfKF6
=dY!-#yg!
privatestaticint getTotalPage(int everyPage, int KKNQ+'?
nRheByYm
totalRecords){ vFi+ExBU
int totalPage = 0; $u::(s}
x<
mN1n/LNi
if(totalRecords % everyPage == 0) '~AR|8q?
totalPage = totalRecords / everyPage; tIo
b
else ^8
cq
qu
totalPage = totalRecords / everyPage + 1 ; ulNMqz\.
J,t`ilT
return totalPage; Lwkl*
} SF[}suL
:[ll$5E.
privatestaticboolean hasPrePage(int currentPage){ J{PNB{v
return currentPage == 1 ? false : true; G@o\D-$
} $)VnHr `hy
uS5ADh
privatestaticboolean hasNextPage(int currentPage, '_FxxLAO
r|Q/:UV?w
int totalPage){ `5 MK(K
:
return currentPage == totalPage || totalPage == 6sNw#pqh
GyQvodqD
0 ? false : true; Qv1cf
} ria.MCe\!
WO[O0!X
r)[Xzn
} Uh3N#O
6-f-/$B
`':G92}#
z#/"5 l
g\G}b
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。 xi15B5_Ps
!Mj28
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 b$>1_wTL
Lm'+z97
做法如下: oh,29Gg
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 =s,}@iqNO4
? w@)3Z=u
的信息,和一个结果集List: 9~4@AGL
java代码: QNGp+xUHJ9
kp^q}iS
7
/XfPF
/*Created on 2005-6-13*/ &M6Zsmo
package com.adt.bo; u4DrZ-v
m`Pk )c0
import java.util.List; Sn[/'V^$a
)&93YrHgC
import org.flyware.util.page.Page; v>0} v)<v
wx_j)Wij6
/** - 9a4ej5
* @author Joa G$;cA:p-j
*/ KxQMPtHstz
publicclass Result { o~26<Lk
^n*:zmD
private Page page; c uHF^l
^#4Ah[:XA
private List content; RhkTN'vO
UD ;UdehC
/** +IG=|X
* The default constructor %#E$wz
*/ gB]jLe
public Result(){ ^m -w@0^z
super(); - #-Bo
} X u2+TK
I6PReVIb
/** qD,/Qu62
* The constructor using fields Dw<bLSaW&
* D_ XOYzN}
* @param page n2Ew0-
* @param content x@tI
*/ kzC4V
public Result(Page page, List content){ ogJ *
this.page = page; $>rKm
this.content = content; +HlZ?1g
} 9hjzOJPuga
|g1Pr9{wy
/** I/go$@E"
* @return Returns the content. p;~oIy\,
*/ .pIO<ZAFT
publicList getContent(){ %$67*pY'JH
return content; +NVXFjPC
} Cm9#FA
2IXtIE
/** ywA7hm
* @return Returns the page. vPAL,
*/ XHh*6Yt_ (
public Page getPage(){
I!T=$Um
return page; b"w@am>&
} e'.CIspN
C]Q}HI#G
/** P 2)/!+`a
* @param content WG
+]
* The content to set. ~bz$] o-<
*/ 9K-,#a
public void setContent(List content){ uobQS!
this.content = content; vb3hDy
} 8WC_CAP
0bteI*L
/** ZtY?X- 4_
* @param page ~Gl5O`w(
* The page to set. FT!X r
*/ :KS"&h{ SY
publicvoid setPage(Page page){ z=Xh
this.page = page; }yw>d\] f
} JA4}Bwn
} k}!'@
xXSfYW
nX8ulGG s
eo^C[#
.
wV\G$|Y
2. 编写业务逻辑接口,并实现它(UserManager, #"fn;
Ok<,_yh
UserManagerImpl) j{6O:d6([$
java代码: 4K*st8+bl-
~RV"_8`V9
`cPZsL
/*Created on 2005-7-15*/ 8Yo;oHk7
package com.adt.service; MeV*]*
B qLL]%F
import net.sf.hibernate.HibernateException; H~bbkql
H3( @Q^9
import org.flyware.util.page.Page; &joP-!"
k]~$AaNq
import com.adt.bo.Result; Hz%<V*\{
r 5t{I2
/** 4RfBXVS
* @author Joa = BbG2k
*/ >ByqM{?
publicinterface UserManager { aLlHR_
@WiTh'w0
public Result listUser(Page page)throws t<"%m)J
&"7+k5O
HibernateException; zL9:e7o
PbFbihg
} Q7\j:.
J0B*V0'zR
}zqo<o
4BeHj~~
k{U[ U1j
java代码: )Br#R:#
|(CgX6 l3
>=;hnLu
/*Created on 2005-7-15*/ `U&'71B^
package com.adt.service.impl; O%w'nz"
204"\mv
import java.util.List; #qv!1$}2
u=Xpu,q
import net.sf.hibernate.HibernateException; P"o|kRO
*$Zy|&[Z
import org.flyware.util.page.Page; +O^} t
import org.flyware.util.page.PageUtil; u?F.%j-
AnK X4Q
import com.adt.bo.Result; ./^8L(
import com.adt.dao.UserDAO; 8dCRSU
import com.adt.exception.ObjectNotFoundException; NE4]i
import com.adt.service.UserManager; #^(Yw|/K
Mi\-
9-
/** ta^$&$l
* @author Joa r! [Qpb-:
*/ xzOn[.Fi
publicclass UserManagerImpl implements UserManager { :#cJZ\YH
~+V$0Q;L
private UserDAO userDAO; p,!IPWo
q_9 8=fyE6
/** xxwbX6^d
* @param userDAO The userDAO to set. FR>[g`1
*/ /U-+ClZi@
publicvoid setUserDAO(UserDAO userDAO){ Cq'{%
this.userDAO = userDAO; HTMg{_r(%
} 7P]i|Q{
^Cvt^cI
/* (non-Javadoc) G( BSe`f
* @see com.adt.service.UserManager#listUser a
<Iikx
Z4E6J'B8
(org.flyware.util.page.Page) 7|jy:F,w%
*/ VLJ]OW8cO
public Result listUser(Page page)throws fxmY,{{
~z")';I|
HibernateException, ObjectNotFoundException { 3Tp8t6*nL
int totalRecords = userDAO.getUserCount(); <N>7.G
if(totalRecords == 0) g_Rp}6g
throw new ObjectNotFoundException \HG4i/V:h
|gHdTb1
("userNotExist"); o{QV'dgu
page = PageUtil.createPage(page, totalRecords); >[:qJ|i%
List users = userDAO.getUserByPage(page); sB$" mJ
returnnew Result(page, users); 'Gamb+[
} $s-B
v`G}sgn
} lCBH3-0^
*{5/" H5
;=k{[g 'gv
-yb7s2o
kD7'BP/#
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _18Z]XtX
5NhAb$q2Y
询,接下来编写UserDAO的代码: qq3/K9 #y
3. UserDAO 和 UserDAOImpl: ?%#no{9
java代码: ]&9=f#k%
R%q:].
salDGsW^
/*Created on 2005-7-15*/ jbUg?4k!
package com.adt.dao; (bpRX$is
-]{
_^
import java.util.List; )>U"WZ'<
#2$wI^O
import org.flyware.util.page.Page; -$_FKny
4'`H H
import net.sf.hibernate.HibernateException; (`4&Y-
L3'isaz&^
/** xg 8R>j
* @author Joa :RwURv+kT
*/ hwQ|'^(@O
publicinterface UserDAO extends BaseDAO { ]6s/y
:SWrx MT
publicList getUserByName(String name)throws /-t!)_zvw
a>9_#_hI
HibernateException; <:T/hm$
[>\e@ =
publicint getUserCount()throws HibernateException; adRIg:2
c5:0`~5Fn
publicList getUserByPage(Page page)throws 5rc3jIXc{|
oiC@ /
HibernateException; !&3"($-U3G
RlbJ4`a
} D>o u,
;uv$>Fauk
!VsdKG)
+nim47
Xwjm T
java代码: V~Z)^.6
XD|Xd|/ {
uEG4^
/*Created on 2005-7-15*/
5e1oxSU
package com.adt.dao.impl; Gpcordt/
PRx- 0S
import java.util.List; &;p}HL,
g1_z=(i`Z
import org.flyware.util.page.Page;
?^MH:o
6@3v+Vf'
import net.sf.hibernate.HibernateException; M?Q\
Hw
import net.sf.hibernate.Query; ZX.,<vumSy
g& f)WQ(
import com.adt.dao.UserDAO; -3wid1SOm
g_k95k3V'
/** b'`XFB#V
* @author Joa B1s&2{L6K
*/ {7MY*&P$,
public class UserDAOImpl extends BaseDAOHibernateImpl v6| [p
,\#j6R,{I
implements UserDAO { kmo#jITa`
' V*}d
/* (non-Javadoc) w7Mh8'P54
* @see com.adt.dao.UserDAO#getUserByName u,}>I%21
r'_#rl
(java.lang.String) z4` :n.
*/ u$aN~6HG
publicList getUserByName(String name)throws SG&H^V8
f)gV2f0t
HibernateException { yx6^ mis4
String querySentence = "FROM user in class `[XH=-p
0;,Y_61
com.adt.po.User WHERE user.name=:name"; ;=E}PbZt2
Query query = getSession().createQuery HZS.%+2
m!!;CbPo
(querySentence); 6 b?K-)kL
query.setParameter("name", name); R/Sm
return query.list(); [u J<]
} ,KF>@3f
6 OvH"/X4
/* (non-Javadoc) zlTLp-^Y
* @see com.adt.dao.UserDAO#getUserCount() SB5qm?pT8<
*/ b"`fS`@/MW
publicint getUserCount()throws HibernateException { B#.xs>{N
int count = 0; H4{7,n
String querySentence = "SELECT count(*) FROM 'O9Yu{M
DYC2bs>
user in class com.adt.po.User"; UEm4):/}
Query query = getSession().createQuery g2*}XS3
$P#+Y,r~\
(querySentence); 2chT^3e
count = ((Integer)query.iterate().next 30(e6T;
+W8#] u|
()).intValue(); :D>flZi
return count; [nX{sM%
} -;RAW1]}Y$
V:+vB "
/* (non-Javadoc) d{(Rs.GuP
* @see com.adt.dao.UserDAO#getUserByPage QJ>=a./
cIkA ~F
(org.flyware.util.page.Page) UYQ@ub
*/ z&um9rXR
publicList getUserByPage(Page page)throws +|K,\
{'U
xlgT1b:6
HibernateException { ?qn4ea-\P
String querySentence = "FROM user in class 5H 1x-b
@y0kX<M
com.adt.po.User"; LW("/
Query query = getSession().createQuery kI5LG6
3W.D^^)eCV
(querySentence); Z3ODZfu>
query.setFirstResult(page.getBeginIndex()) W=|'&UU Ul
.setMaxResults(page.getEveryPage()); Gz8JOl
return query.list(); LUz`P6
} y^kC2DS
a{%EHL,F
} U~c9PqjZ
R iV]SgV9
_+}hId
YhAO
rEU1
VvE
至此,一个完整的分页程序完成。前台的只需要调用 ;;U&mhz`
ZX{eggXl
userManager.listUser(page)即可得到一个Page对象和结果集对象 P/]8+_K
BCd0X. m(
的综合体,而传入的参数page对象则可以由前台传入,如果用 V2tA!II-s
p!?7;
webwork,甚至可以直接在配置文件中指定。 oW(8bd)
[`KQ\4u
下面给出一个webwork调用示例: 9{A*[.XK]
java代码: 09G]t1!,
TLVfu4
xcJvXp
/*Created on 2005-6-17*/ f)Z'#[A*t7
package com.adt.action.user; X\<a|/{V A
Y!|};
import java.util.List; (.{. "
m5KLi
&R
import org.apache.commons.logging.Log; QEx&AT
import org.apache.commons.logging.LogFactory; =Q|s[F
import org.flyware.util.page.Page; S%7bM~J@
[!ZYtp?Hf
import com.adt.bo.Result; L9whgXD
import com.adt.service.UserService; ~IQjQz?
import com.opensymphony.xwork.Action; k<"N^+GSz
=aehhs>
/** O&">%aU1I
* @author Joa kaDn=
={YM
*/ &N%-.&t'
publicclass ListUser implementsAction{ )oS~ish
d{C8}U
privatestaticfinal Log logger = LogFactory.getLog U2JxzHXZ
y>RqA*J
(ListUser.class); j{zVVT
' 94HVag
private UserService userService; T16B2|C"Y
`X`|]mWj
private Page page; kYd=DY
rj5)b:c}
privateList users; h 'is#X 6:
^AUQsRA7PZ
/* #`"B
YFV[E
* (non-Javadoc) !A_KCM:Ym
* VrFI5_M/
* @see com.opensymphony.xwork.Action#execute() mj y+_
*/ o%Qn%gaX
publicString execute()throwsException{ wo^1%:@/2
Result result = userService.listUser(page); ^$lsmF]^
page = result.getPage(); o`}8ZtD
users = result.getContent(); 2TaHWw<A
return SUCCESS; Ax!fvcsN
} O}7aX '
\l 3M\$oS>
/**
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* @return Returns the page. TR{dNO!q
*/ ayA_[{j%X
public Page getPage(){ :!,.c$M
return page; 81wmKqDEs
} eA/}$.R
a6op
/** WxF@'kdn*,
* @return Returns the users. T9'5V@
*/ a\I`:RO=<Z
publicList getUsers(){ y"nCT3
return users; Mz6|#P}.s
} Z?w=-
UX'tdB
!A
/** i{>YQ
* @param page Lismo#
* The page to set. *P[N.5{
*/ h^b=
publicvoid setPage(Page page){ ]g9n#$|.
this.page = page; =iPQ\_ON@
} u\UI6/
jTY{MY Jh
/** e?-LB
* @param users G@S'_
* The users to set. 11yS2D
*/ u+8?'ZT,
publicvoid setUsers(List users){ 2l4`h)_q
this.users = users; 3-2?mV>5
} C6b(\#g(
XecU&
/** _Hq)mF
* @param userService gr$H?|n l
* The userService to set. )i>T\B
*/ DZ|/#- k
publicvoid setUserService(UserService userService){ 3bB%@^<
this.userService = userService; gH/k}M7tA#
} )$I"LyK)
} ~bJ*LM?wOP
gJBk&SDgtP
W-ECmw(
rYr.mX
cNqw(\rr
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, :y[tZ&*<_?
Q|cA8Fn
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 Ad`jV_z
1Aa=&B2
么只需要: Yy0m &3[
java代码: <8/lHQ^\)
YcBAW4B`
fBt7#Tc=U
<?xml version="1.0"?> j-etEWOTr
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork GEi^3UD
&rxR"^x\
1.0//EN" "http://www.opensymphony.com/xwork/xwork- zX/9^+p:
3836Di:{
1.0.dtd"> Cqk6I gw
LIHf]+
<xwork> DnPV
Tp(>
doaqHri\,
<package name="user" extends="webwork- "A9 c]
cb~m==G
interceptors"> \>-%OcYlM
6e;.}i
<!-- The default interceptor stack name \<A@Nf"
tI(co5 W
--> .{W)E
<default-interceptor-ref n-_-;TYH
^KMZB
name="myDefaultWebStack"/> U9B|u`72
%G s!oD
<action name="listUser" /=qn1
>j$CM:w
class="com.adt.action.user.ListUser"> \D
#NO
<param g @lAk%V4
mWM!6"
name="page.everyPage">10</param> ZK]C!8\2|
<result |bz,cvlP
W
]={{$}8.
name="success">/user/user_list.jsp</result> bdCpGG9
</action> etH%E aF[
dGzZ_Vf
</package> Oj0/[(D-
zKk2>.
</xwork> g< {jgF
bXiT}5mJU
j7 D\O
zW^@\kB0D
NUH#
/P0%4aWu=
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 H;$O CDRC
|ldRs'c{
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 6(}8[i:
SpY%2Y.Dy
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 iB 5 Se
# -Ts]4v
UpS`KgF"v
>2~q{e
K_B-KK(^
我写的一个用于分页的类,用了泛型了,hoho pemb2HQ'4j
g+k0Fw]!
java代码: Ro?aDrQ
`:A`%Fg8<
eJ#q! <
package com.intokr.util; ``}EbOMG
8:,l+[\
import java.util.List; LEkO#F(
:WTO*M
/** \qqt/
* 用于分页的类<br> Hay`lA2@
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?t+Kp9@aZ
* ,m:YZ;J(Xd
* @version 0.01 }CA oB::&
* @author cheng Uok?FEN
*/ lM5Xw
public class Paginator<E> { =?3D:k7z
privateint count = 0; // 总记录数 t3b%f`D
privateint p = 1; // 页编号 N$H0o+9-Y
privateint num = 20; // 每页的记录数 RI"A'/56
privateList<E> results = null; // 结果 -lm\~VZT3
0p_/eWww-
/** nj~1y')
* 结果总数 C_Y^<
*/ ^~2GhveBV
publicint getCount(){ 0t1WvW
return count; )sVz;rF<
} 5/Q^p"
<ok/2v
publicvoid setCount(int count){ %uyRpG3,
this.count = count; YZdp/X6x
} ZO+c-!%[(
&gZ5dTj>
/** jYRwtP\
* 本结果所在的页码,从1开始 #!KbqRt
* .Kr?vD^nG
* @return Returns the pageNo. v*1UNXU\
*/ uHUicZf.
publicint getP(){ V7!x-E/
return p; XFPWW ,
} DGTSk9iK(
1_!*R]a q
/** :~pPB#)nk
* if(p<=0) p=1 m0W5O gk
* 1+PLj[;jJ:
* @param p <DCrYt!1}c
*/ Y6/'gg'&5
publicvoid setP(int p){ u~6`9'Ms
if(p <= 0) b}p 0&%I
p = 1; }\B`tAN
this.p = p; hV/$6 8A_
} 7^h?<X\
!L+*.k:
/** |Z<NM#1
* 每页记录数量 `(?E-~#'
*/ qIa|sV\w0
publicint getNum(){ Tz1St{s\
return num; {mMrD 5
} T&I*8 R~
!j6]k^ra
/** NWSBqL5v
* if(num<1) num=1 q3B#rje>h
*/ [ottUS@
publicvoid setNum(int num){ &)O X*y
if(num < 1) `AeId/A4n
num = 1; `(<XdlOj
this.num = num; u<./ddC
} Y!v `0z
G:$wdT(u
/** Iu^#+n
* 获得总页数 k`6T% [D]
*/ ? r=cLC
publicint getPageNum(){ )R+@vh#Q<$
return(count - 1) / num + 1; W\o(f W
}
eP$0TDZ
xXM`f0s@+]
/** ]QM6d(zDA
* 获得本页的开始编号,为 (p-1)*num+1 )Fk%,H-1
*/ `9Zoq=/
publicint getStart(){ .0S.7w3dZo
return(p - 1) * num + 1; b40zYH`'{
} iV[g.sP-
s(J,TS#I]
/** B0NKav
* @return Returns the results. #Na3eHT
*/ 1Dg\\aUk
publicList<E> getResults(){ UHF.R>Ry
return results; ?h"+q8&
} Xz&Hfs"/J
kehv85
public void setResults(List<E> results){ <7/ _Vs)F0
this.results = results; $%"i|KTsv:
} V}=9S@$o
gYfN?A*`_
public String toString(){ \zw0*;&U
StringBuilder buff = new StringBuilder {3]g3mj
hWwh`Vw%
(); 1+v&SU
buff.append("{"); \T'uFy9&a
buff.append("count:").append(count); 11}X2j~Ww
buff.append(",p:").append(p); W~k"`g7uu
buff.append(",nump:").append(num); o-Pa3L=
buff.append(",results:").append ge9j:S{
9%j_"+<c
(results); N&U=5c`Q'
buff.append("}"); *fso6j#%
return buff.toString(); (p'yya{(
} >_(Xb%w
"]Wrir?l
} +^YXqOXU
E!&A[TlX\
-bu.Ar-#;h