Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 >vR2K^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )||CU]"b?
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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 g7lPQ_A*
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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 1|AY&u%fiP
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。 :`lP+y?a1
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分页支持类: Sx (E'?]
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java代码: vR>GE?s6
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package com.javaeye.common.util; F@#p
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import java.util.List; 4#.Q|vyl]"
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publicclass PaginationSupport { :."6 g)T
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publicfinalstaticint PAGESIZE = 30; mxu !$wx
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privateint pageSize = PAGESIZE; "c?31$6
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privateList items; ];5Auh0o
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privateint totalCount; /1D.Ud^
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privateint[] indexes = newint[0]; 5sj$XA?5
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@:
privateint startIndex = 0; \zwm:@lG
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public PaginationSupport(List items, int U_.}V
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totalCount){ \rO!lvX
setPageSize(PAGESIZE); +\u\BJ!LAJ
setTotalCount(totalCount); f! )yE`4-
setItems(items); 'm"Ez'sS
setStartIndex(0); a#x@e?GvI
} DO9K
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public PaginationSupport(List items, int ]0SqLe
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totalCount, int startIndex){ ]"htOO
setPageSize(PAGESIZE); \rg;xZa5
setTotalCount(totalCount); F\GNLi
setItems(items); -N6ek`
setStartIndex(startIndex); B52dZ b
} d0f(U k
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public PaginationSupport(List items, int =P_*.SgR
94]i|2qj*
totalCount, int pageSize, int startIndex){ y+V>,W)r7
setPageSize(pageSize); cM4{ e^
setTotalCount(totalCount); rYg%B6Fp
setItems(items); (ip3{d{CT]
setStartIndex(startIndex); =Zsxl]h
} e**'[3Y
/[ft{:#&t
publicList getItems(){ z]LVq k
return items; 0I do_V
} dTlEEgR
jxt]Z3a ~0
publicvoid setItems(List items){ TZ3gJ6 Cb
this.items = items; {*r!oD!'
} GU 9p'E
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publicint getPageSize(){ R9D2cu,{
return pageSize; 6+"gk(
} &p*rEs
j~>J?w9<O
publicvoid setPageSize(int pageSize){ R6:m@
this.pageSize = pageSize; ipt]qJFd
} }jU)s{>fb
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publicint getTotalCount(){ F g'{K%t4
return totalCount; {sj{3I u
} vQy<%[QO
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publicvoid setTotalCount(int totalCount){ %K06owV(S)
if(totalCount > 0){ +Jn\`4/J:
this.totalCount = totalCount; 0ia-D`^me
int count = totalCount / v6E5#pse8
g:U
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pageSize; ;XlCd[J<
if(totalCount % pageSize > 0) Ol>/^3a=
count++; +qqCk
indexes = newint[count]; hstGe>f[6
for(int i = 0; i < count; i++){ RyM29uD
indexes = pageSize * <1:I[b
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i; #e[r0f?U
} kho0@o+'^
}else{ : t75iB=
this.totalCount = 0; :<0lC j
} Qv;b$by3
} =4&"fZ"v
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publicint[] getIndexes(){ sEZ2DnDI
return indexes; Y$j!-l5z
} JRE\R&>g
w
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publicvoid setIndexes(int[] indexes){ /+. m.TF
this.indexes = indexes; 9#~jlq(
} *KU:D Y{
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publicint getStartIndex(){ V%C'@m(/SZ
return startIndex; /Bk`3~]E>
} -yu$Mm
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publicvoid setStartIndex(int startIndex){ 6{g&9~V
if(totalCount <= 0) _G/uDP%
this.startIndex = 0; l <Z7bo
elseif(startIndex >= totalCount) ,W/Y@ScC
this.startIndex = indexes AI,E9
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[indexes.length - 1]; W3^^aD-
elseif(startIndex < 0) Ywcgt|
this.startIndex = 0; (l(d0g&p>
else{ @ Yo*h"s
this.startIndex = indexes &XXr5ne~C
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[startIndex / pageSize]; 8|+@A1)&4
} rg]z
} * <?KOM
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publicint getNextIndex(){ q%)."10}]
int nextIndex = getStartIndex() + T$;BZ=_
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pageSize; 55,2eg#{O
if(nextIndex >= totalCount) XXD4T9Wy
return getStartIndex(); ,Hp7`I>/
else zU4*FXt
return nextIndex; 3-[+g}kak?
} w7\
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qK%#$JgqA
publicint getPreviousIndex(){ `nc=@" 1
int previousIndex = getStartIndex() - 9c5DEq
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pageSize; KmWd$Qy,
if(previousIndex < 0) 9tmnx')_
return0; *w6F0>u
else >J:liB|(
return previousIndex; ]9wTAb
} bJeF1LjS
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} &7{yk$]*
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抽象业务类 zP|^@Homk
java代码: bJynUZ
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/** iWkC:fQz
* Created on 2005-7-12 V%`\x\Xat
*/ o}52Qio
package com.javaeye.common.business; n9Vr*RKM)
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import java.io.Serializable; ws$kwSHq
import java.util.List; /38XaKc{6
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import org.hibernate.Criteria; jm'^>p,9G
import org.hibernate.HibernateException; UI~ hB4V$]
import org.hibernate.Session; /U0,%
import org.hibernate.criterion.DetachedCriteria; bH%d*
import org.hibernate.criterion.Projections; E[FE-{B#
import '<6DLtZl
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org.springframework.orm.hibernate3.HibernateCallback; XXXQA Y-,C
import Sh:_YD^(
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org.springframework.orm.hibernate3.support.HibernateDaoS o76{;Bl\O
,Z8)DC=
upport; | _nBiHjNn
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import com.javaeye.common.util.PaginationSupport; \AB)L{
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public abstract class AbstractManager extends U[Lr+nKo\
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HibernateDaoSupport { lnK#q.]
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privateboolean cacheQueries = false; $M$-c{>s
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privateString queryCacheRegion; }-T,cA_H|
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publicvoid setCacheQueries(boolean c IPOI'3d
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cacheQueries){ >.uIp4@(
this.cacheQueries = cacheQueries; RSnBG"
} 3`Xzp
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publicvoid setQueryCacheRegion(String K{ntl-D&y
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queryCacheRegion){ K87yQOjPv
this.queryCacheRegion = s(r4m/
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queryCacheRegion; Y+5aT(6O
} ClNuO
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publicvoid save(finalObject entity){ 20I/En
getHibernateTemplate().save(entity); e%IbME]x
} RrdLh z2N
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publicvoid persist(finalObject entity){ ,wngS=
getHibernateTemplate().save(entity); (O&HCT|
} P(a}OlG
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publicvoid update(finalObject entity){ \9`.jB~<
getHibernateTemplate().update(entity); |7${E^u
} gMp' S
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publicvoid delete(finalObject entity){ Pc<0kQg
getHibernateTemplate().delete(entity);
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} DWN9_*{
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publicObject load(finalClass entity, #w:nj1{_
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finalSerializable id){ nj1PR`AE
return getHibernateTemplate().load ^F&j;8U
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(entity, id); Xg;;<
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} l=x(
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publicObject get(finalClass entity, C~C`K%7
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finalSerializable id){ ) $0>L5d:
return getHibernateTemplate().get +r&:c[
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(entity, id); ZB}A^X
} "oyBF CW
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publicList findAll(finalClass entity){ ~Yc!~Rz
return getHibernateTemplate().find("from O%haaL\
5=%KK3
" + entity.getName()); 7p1B"%
} .Lu3LVS
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publicList findByNamedQuery(finalString eN\+
@;N(3| n7
namedQuery){ i0zrXaKV
return getHibernateTemplate b*/Mco 9O
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().findByNamedQuery(namedQuery); X{<taD2~
} M|zTs\1I
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publicList findByNamedQuery(finalString query, ^P*-bV4
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finalObject parameter){ D wr 9}Z-]
return getHibernateTemplate 1
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().findByNamedQuery(query, parameter); B*w]yL(
} .!Kqcz% A
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publicList findByNamedQuery(finalString query, cbs ;
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finalObject[] parameters){ ) xKW
return getHibernateTemplate g"(@+\XZH"
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().findByNamedQuery(query, parameters); ~*9Ue@
} _N)&<'lB<
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publicList find(finalString query){ D$*o}*mb
return getHibernateTemplate().find =8%*Rrj^
&%;n9K
(query); rHk,OC
} M ?AX:0
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publicList find(finalString query, finalObject ^E:-Uy
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parameter){ ;R
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return getHibernateTemplate().find 72.Msnn
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(query, parameter); ewHs ]V+U
} dv+ZxP%g
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public PaginationSupport findPageByCriteria jzGK(%sw"
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(final DetachedCriteria detachedCriteria){ {@3v$W~7M
return findPageByCriteria :K"~PrHm
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); :FfEjNil
} q-ko)]
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public PaginationSupport findPageByCriteria `wQs$!a
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(final DetachedCriteria detachedCriteria, finalint i3Bpim.
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startIndex){ :#35mBe}k
return findPageByCriteria '3Q~y"C+4
dr+(C[=
(detachedCriteria, PaginationSupport.PAGESIZE, XWQ `]m)
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startIndex); EP>Lh7E9n
} oP%5ymL%J
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public PaginationSupport findPageByCriteria U]_WX(4 @
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(final DetachedCriteria detachedCriteria, finalint 5J|S6x\
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pageSize, L jTSu9I>
finalint startIndex){ .P/0`A{&
return(PaginationSupport) :KA)4[#;W
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getHibernateTemplate().execute(new HibernateCallback(){ Z]oGE@!
n"
publicObject doInHibernate e&U$;sS`
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(Session session)throws HibernateException { iLNUydiS
Criteria criteria = ]+3M\ ib
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detachedCriteria.getExecutableCriteria(session); _*%K!%}l=
int totalCount = !4=_l6kg~+
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((Integer) criteria.setProjection(Projections.rowCount Rvx7}ZL!
*<y9.\zY<
()).uniqueResult()).intValue(); j/=Tj'S?D
criteria.setProjection 7>@/*S{X
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(null); ;AB ,:*
List items = sr@XumT
}_/h~D9-T#
criteria.setFirstResult(startIndex).setMaxResults & c9Fw:f;
!=:MG#p
(pageSize).list(); <H@!Xw;
PaginationSupport ps = -LK(C`gB
f=O>\
new PaginationSupport(items, totalCount, pageSize, g+r{>x
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startIndex); PZg]zz=V4
return ps; uvv-lAbjw
} [%,=0P}
}, true); PyxN _agf
}
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public List findAllByCriteria(final dB/I2uGl>
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DetachedCriteria detachedCriteria){ L\b_,'I
return(List) getHibernateTemplate A'-YwbY
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().execute(new HibernateCallback(){ zYF&Dv/u/
publicObject doInHibernate )0d".Q|v4
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(Session session)throws HibernateException { IeI%X\G
Criteria criteria = NWwtq&pz2
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detachedCriteria.getExecutableCriteria(session); 35kbE'
return criteria.list(); OSi9J.]O
} ]%8;c
}, true); ;U3Vows
} *"sDaN0@R
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public int getCountByCriteria(final gL"Q.ybA
#&KE_n
DetachedCriteria detachedCriteria){ )mVYqlU"
Integer count = (Integer) >t2)Z|1
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getHibernateTemplate().execute(new HibernateCallback(){ mf[79:90^
publicObject doInHibernate o?
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(Session session)throws HibernateException { D c.W vUM
Criteria criteria = j=% -b]
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detachedCriteria.getExecutableCriteria(session); afq
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return n(Op<
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criteria.setProjection(Projections.rowCount {&qsh9ob
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()).uniqueResult(); Ki;5 =)
} <KPx0g?=b
}, true); rB|:r\Z(jG
return count.intValue(); -+@~*$
d
} 1V$B^/ _
} -"9)c^KVx
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用户在web层构造查询条件detachedCriteria,和可选的 NfN6KDd]2L
i j;'4GzQL
startIndex,调用业务bean的相应findByCriteria方法,返回一个 z( [ $,e\
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PaginationSupport的实例ps。 `z`;eR2oX
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ps.getItems()得到已分页好的结果集 n8aiGnd=v
ps.getIndexes()得到分页索引的数组 "dOY_@kg
ps.getTotalCount()得到总结果数 S9+gVR8]C
ps.getStartIndex()当前分页索引 Dq4}VkY
ps.getNextIndex()下一页索引 J&1N8Wk)
ps.getPreviousIndex()上一页索引 jt?%03iuk
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 6.=1k
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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 tzJtd
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一下代码重构了。 $:Zxb
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我把原本我的做法也提供出来供大家讨论吧: Ap18qp
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首先,为了实现分页查询,我封装了一个Page类: GQxJ (f
java代码: 0Hf-~6
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/*Created on 2005-4-14*/ k
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package org.flyware.util.page; :8T@96]P
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/** vG:,oB}
* @author Joa me\)JCZpb{
* 5*Iz3vTq
*/ ')~HOCBSE
publicclass Page { IWnW(>V
D"5~-9<
/** imply if the page has previous page */ :\We =oX
privateboolean hasPrePage; iAhRlQ{Qu
>g=:01z9
/** imply if the page has next page */ sOenR6J<$
privateboolean hasNextPage; T5G+^XDA
o62gLO]z@
/** the number of every page */ !Xce iQu
privateint everyPage; J1MnkxJmpQ
#R|4(HlL
/** the total page number */ b~echOj
privateint totalPage; +Q&@2 oY"
u:?RdB}B_@
/** the number of current page */ v>l?d27R
privateint currentPage; [C\?}.+v
mt7:`-
/** the begin index of the records by the current :7*\|2zA
r${a
S@F
query */ ^r$5];n
privateint beginIndex; y+h=x4t
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EatDT*!
/** The default constructor */ !OemS7{
public Page(){ oWOZ0]H1
Zwl?*t\D
} Os+=}
1-<Xi-=^{t
/** construct the page by everyPage qILr+zH
* @param everyPage <3OV
* */ |[ofc!/
public Page(int everyPage){ $nWmoe)
this.everyPage = everyPage; Yb*}2
} Xu0*sQK
#y%Ao\~kG
/** The whole constructor */ 9a unv
public Page(boolean hasPrePage, boolean hasNextPage, ktb.fhO
^ jA}*YP
#{sb>^BF
int everyPage, int totalPage, gUQCKNw
int currentPage, int beginIndex){ &2^V<(19
this.hasPrePage = hasPrePage; E>v~B;@
this.hasNextPage = hasNextPage; lN"rhZ
this.everyPage = everyPage; UI'eD)WR
this.totalPage = totalPage; huE#VY
/t
this.currentPage = currentPage; Uy=eHwU?J
this.beginIndex = beginIndex; Dr609(zg^
} f}4h}Cq
hG]20n2
/** E}+A)7mA
* @return /@e\I0P^
* Returns the beginIndex. ,"v%
*/ 9X~^w_cdk
publicint getBeginIndex(){ 2(|V1]6D?
return beginIndex; I+SL0
} T@.CwV
u@Lu.t!],
/** @hv]
[(<
* @param beginIndex -Zh+5;8g
* The beginIndex to set. Qfi5fp=f
*/ lQjq6Fl2
publicvoid setBeginIndex(int beginIndex){ .b"e`Bw_=
this.beginIndex = beginIndex; IA'AA|v
} up?8Pq*
*V}}3Degh
/** 8wd2\J,]
* @return gS ]'^Sr
* Returns the currentPage. dewu@
*/ # L R[6l
publicint getCurrentPage(){ ] $*cmk(Y
return currentPage; &0`L; 1R
} q ^?{6}sy
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/** +Xk!)Ge5E*
* @param currentPage 9S^-qQH3}
* The currentPage to set. OZ&aTm :
*/ KN=Orx7Gy
publicvoid setCurrentPage(int currentPage){ }e$);A|
this.currentPage = currentPage; q0}LfXql8
} 7iJlW&W
Kh> ^;`h
/** c-,/qn/
* @return LQe<mZ<
* Returns the everyPage. K;Ktx>Z/
*/ Hd:ZE::Q'#
publicint getEveryPage(){ "6ZatRUd
return everyPage; .d2s4q\
} cg4,PI%hz
A-<qr6q
/** zy.Ok 49
* @param everyPage XjC+kH
* The everyPage to set. $]9d((u4
*/ p`It=16trT
publicvoid setEveryPage(int everyPage){ pD{Li\LY
this.everyPage = everyPage; 1+]e?
} B:l(`G
@"6BvGU2s
/** Y9C] -zEv
* @return zr,jaR;
* Returns the hasNextPage. Cpr}*A
*/ p|Ln;aYc
publicboolean getHasNextPage(){ =3@^TW(j
return hasNextPage; JS4pJe\q
} |Q{ l]D
kmf4ax
h1
/** 8=$@azG
* @param hasNextPage FKaY w
* The hasNextPage to set. ]}9EBf
*/ iU &V}p
publicvoid setHasNextPage(boolean hasNextPage){ :%Bo)0a9
this.hasNextPage = hasNextPage; xKxWtZ0
} e}kG1C8
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/** |YH1q1l
* @return tW,<Pe
* Returns the hasPrePage. TGg* (6'z
*/ =U:iR
publicboolean getHasPrePage(){ P<bA~%<7"[
return hasPrePage; l|DOsI'r
} |(w x6H:
k&Sg`'LG8
/** 'h:4 Fzo<
* @param hasPrePage _PuMZjGL
* The hasPrePage to set. 3vy5JTCz~
*/ j"f]pzg&
publicvoid setHasPrePage(boolean hasPrePage){ )%Y$FLB
this.hasPrePage = hasPrePage; XOxm<3gXn
} UZ
y
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/** S"lcePN
* @return Returns the totalPage. $jm'uDvm
* A/'G.H
*/ Dhq7qz
publicint getTotalPage(){ 0-=QQOART\
return totalPage; 2WKA] l;
} Tux~4W
R^D~ic
N
/** !OiP<8 ,H
* @param totalPage Blu^\:?#z-
* The totalPage to set. JAgec` T%
*/ |u03~L9G
publicvoid setTotalPage(int totalPage){ _yU
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this.totalPage = totalPage; l9n8v\8,o
} &4]%&mX)-
,O2Uj3"
} K\ZKVn
.[~E}O
^b&aDm~(7
J9{B
[3j]r{0I
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 'I;pS)sb
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个PageUtil,负责对Page对象进行构造: xe}"0'g
java代码: ?onZ:s2
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HgbJsv$
/*Created on 2005-4-14*/ t0?\5q
package org.flyware.util.page; .NZ_dz$c
~aBALD0D;
import org.apache.commons.logging.Log; S0\:1B
import org.apache.commons.logging.LogFactory; R D)dw
^5xY&1j
/** P[^!Uq[0n7
* @author Joa N@*v'MEko%
* nc([e9_9v
*/ jo+T!CUM'
publicclass PageUtil { T"3WB o
;5oY)1
privatestaticfinal Log logger = LogFactory.getLog +>{{91mN
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(PageUtil.class); az7L0pp
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/** C}wmoYikV
* Use the origin page to create a new page {DAwkJvb]
* @param page Rg+V;C
C~
* @param totalRecords xqLLoSte
* @return GQT|T0>Ro
*/ ,>e)8
publicstatic Page createPage(Page page, int i_ I`Y
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totalRecords){ 9].!mpR
return createPage(page.getEveryPage(), I 8e{%PK
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page.getCurrentPage(), totalRecords); )4 "G1R`3
} D{\hPv
ASPfzW2
/** pZF`+642
* the basic page utils not including exception lZ'NLbK
,f4Hl%T;
handler e>X&[\T
* @param everyPage y1FS?hSD0
* @param currentPage e~jp< 4
* @param totalRecords yG{'hx6H
* @return page >|mmJ4T
*/ .z)E
publicstatic Page createPage(int everyPage, int BIS5u4
q>f1V3
currentPage, int totalRecords){ Q;Xb-\\
everyPage = getEveryPage(everyPage); q=Q5s?sQc
currentPage = getCurrentPage(currentPage); N(6|TE2
int beginIndex = getBeginIndex(everyPage, H"].G^V\6
Lw1~$rZg
currentPage); Tj@s \@hv
int totalPage = getTotalPage(everyPage, 0vf2wBK'T
pv;}Sv$
]-
totalRecords); l. !5/\
boolean hasNextPage = hasNextPage(currentPage, } D{y
u+)
|-=^5q5
totalPage); dKi+~m'w
boolean hasPrePage = hasPrePage(currentPage); T ^%$
px".pYr0
returnnew Page(hasPrePage, hasNextPage, S"V|BU
everyPage, totalPage, JM@MNS_||(
currentPage, mQ:lj$Gf
44]/rP_m
beginIndex); 9^x'x@6
} &qF
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privatestaticint getEveryPage(int everyPage){ FlgK:=Fmj
return everyPage == 0 ? 10 : everyPage; V1,O7m+F2
} [C.Pzo
;WWUxrWif
privatestaticint getCurrentPage(int currentPage){ VYMs`d[
return currentPage == 0 ? 1 : currentPage; c"H*9u:
} gfR B
&FW|O(]
privatestaticint getBeginIndex(int everyPage, int *C}vy`X
1-Sc@WXd
currentPage){ f@]4udc e
return(currentPage - 1) * everyPage; 'OK)[\
} P0Z1cN}
^ dM,K
p
privatestaticint getTotalPage(int everyPage, int zkA"2dh
uwU;glT
totalRecords){ i9 8T+{4
int totalPage = 0; gk1I1)p
YP5V~-O/
if(totalRecords % everyPage == 0) .r[kNh@
b%
totalPage = totalRecords / everyPage; R bM`"wrZ
else vdyLwBz:
totalPage = totalRecords / everyPage + 1 ; dX^OV$
]*'V#;s
return totalPage; 0L9z[2sj
} hW P$U
k}(C.`.
privatestaticboolean hasPrePage(int currentPage){ :U$<h
return currentPage == 1 ? false : true; Lp`q[Z*
} hB]4Tn5H
b%z4u0
privatestaticboolean hasNextPage(int currentPage, )#%k/4(Y
82O#Fe q
int totalPage){ 0B7cpw>_J
return currentPage == totalPage || totalPage == .BuXg<`
pdUrVmW "'
0 ? false : true; FZ)_WaqGf
} <DxUqCE
:<=A1>&8
U ]Ek5p
} eZ'J,;
s,!+wHv_8
?ey!wcv~
*G"L]Nq#
+]
s"* 'V$
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。 hN=YC\l
QVA)&k'T,
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 n}Pz:
h&|q>M3
做法如下: @)owj^sA
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 2K0HN
]@wee 08
的信息,和一个结果集List: 6`Zx\bPDm
java代码: ;5urIYd
xXp$Nm]:
ckY,6e"6
/*Created on 2005-6-13*/ (qG |.a
package com.adt.bo; PQ9.aJdw@-
p~1!O]qLt
import java.util.List; +KGZk?%
#+I)<a7\
import org.flyware.util.page.Page; ]k
&Y )
"ph&hd}S
/** 5v<X-8"
* @author Joa ;<i `6e
*/ c'ExZ)RJ
publicclass Result { J\VG/)E
^LO=&Cq
private Page page; {y-7xg~}
~?T*D*
private List content; #z$FxZT<b
+0lvQVdp}
/** x =7hOI5u
* The default constructor >*r H Nf
*/ gb:)t}|
public Result(){ >T:
Yp<
super(); %P05k
} 6P@3UQ)}s
8#b>4Dx
/** 5:ca6H
* The constructor using fields t
1gH9
* \i%h/Ao
* @param page $n>|9(K8
* @param content ?|Y/&/;%I
*/ f7NK0kuA
public Result(Page page, List content){ =23JE'^=
this.page = page; M`^;h: DN^
this.content = content; "9mJ$us
} gwHNz5 a*V
TNs;#Q
/** }$E cNm$%
* @return Returns the content. ?+EN.P[;3
*/ B^`'2$3
publicList getContent(){ q):Ph&'r
return content; ,I# X[^/
} ~Mu=,OT
;/.ZjTRw
/** LU
"e9
* @return Returns the page. a:nMW '!
*/ MW&ww14
public Page getPage(){ O
:P%gz4
return page; :"BZK5{8
} V-rzn171Q)
'fB/6[bd
/**
wbg_%h:
* @param content ,jVj9m
* The content to set. =pHWqGOD
*/ p<hV7x-{
public void setContent(List content){ jn[%@zD }
this.content = content; Ji%6/zV
} J`F][ A
;533;(d*o
/** TK"!z(p
* @param page K5(:UIWx
* The page to set. 2x3'm
*/ ai/VbV'|
publicvoid setPage(Page page){ zQsu~8PX
this.page = page; XHq8p[F
} @H'pvFLK?
} pMJK?- )
OG}auM4
cQj{[Wt4
G}.t!"
<3]Qrjl
,b
2. 编写业务逻辑接口,并实现它(UserManager, &j2fh!\4
z>_jC+
UserManagerImpl) b.Wf*I?
java代码: SVvR]T&_
?9<byEO%M
[p3)C<;ZC
/*Created on 2005-7-15*/ \gd.Bl
package com.adt.service; _Se~bkw?v
-t28"jyj
import net.sf.hibernate.HibernateException; 'W0?XaEk-
RJMrSz$
import org.flyware.util.page.Page; ?R2`RvQ
gm;6v30e
import com.adt.bo.Result; 'k2Z$+
/*B^@G |]'
/** j\t"4=,n
* @author Joa +/idq
*/ mRIW9V
publicinterface UserManager { U?dd+2^};t
"],amJ
public Result listUser(Page page)throws gwFHp.mE
Gx75EQ2
HibernateException; jtWI@04o09
w`~j(G4N
} x @EEMO1_"
G[V?#7.
\qPgQsy4
?kvc`7>
?cQ
java代码: lW F=bz0
gHS;RF9
I<Vh
Eo,
/*Created on 2005-7-15*/ -QaS/WO_
package com.adt.service.impl; y@!kp*0
0q_Ol]<V
import java.util.List; J('p'SlI
r{m"E^K,
import net.sf.hibernate.HibernateException; 8e_ITqV%
=A,32&;@N
import org.flyware.util.page.Page; V0p@wG3
import org.flyware.util.page.PageUtil; Q^qG=
x)@G+I\u
import com.adt.bo.Result; @21G[!%J
import com.adt.dao.UserDAO; ]#hT!VOd
import com.adt.exception.ObjectNotFoundException; h[c
HCVM:
import com.adt.service.UserManager; =Mc]FCV
V%~u8b
/** f#xqu+)Z
* @author Joa F*WWv&\X
*/ qcxq-HS2'
publicclass UserManagerImpl implements UserManager { |q$br-0+
7. y
L>
private UserDAO userDAO; MmOGt!}9A
!Xt=+aKN
/** 6"Tr$E
* @param userDAO The userDAO to set. 64s9Dy@%F
*/ ~g2ColFhu
publicvoid setUserDAO(UserDAO userDAO){ 7{oG4X!
this.userDAO = userDAO; SZ}t_w `
} Mnpb".VU#T
U4*5o~!=S
/* (non-Javadoc) 45`Gv
* @see com.adt.service.UserManager#listUser "HR
&Rf k
8;3T65KY
(org.flyware.util.page.Page) 7M:0%n$
*/ \$J!B&i
public Result listUser(Page page)throws VHsNz WI
%^RlE@l9
HibernateException, ObjectNotFoundException { r ]1|I6:&)
int totalRecords = userDAO.getUserCount(); g<~[k?~J
if(totalRecords == 0) hB:R8Y^?H
throw new ObjectNotFoundException Fs:l"5~>1
(JC -4X_
("userNotExist"); 6.tppAO+
page = PageUtil.createPage(page, totalRecords); di6A.N5A
List users = userDAO.getUserByPage(page); s#sr1[9}G
returnnew Result(page, users); F0Xv84:O
} 2l+O|R
>*A\/Da]j
} La}=Ng
N i^pP@('
?Gr<9e2Eo
->vfQwBFd
0-Xpq,0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 aisX56Lc
57+^T}/>
询,接下来编写UserDAO的代码: ?,|_<'$4T
3. UserDAO 和 UserDAOImpl: 6X5m1+ Oi^
java代码: De|@}@
z'r .LBnh
iXC/?
EK4
/*Created on 2005-7-15*/ U^ BB|
package com.adt.dao; xtU)3I=F%
:i*JlKHJd
import java.util.List; cd}TDd(H%
V]}/e!XK\
import org.flyware.util.page.Page; #UU}lG
t]FFGnBZ
import net.sf.hibernate.HibernateException; +u_mT$|T
y)U8\
/** O3*Vilx
* @author Joa -tx)7KV-
*/ qd3B>f
publicinterface UserDAO extends BaseDAO { 2!dIW5I
UR-e'Z&]
publicList getUserByName(String name)throws u
` 9Eh;
/eR @&!D '
HibernateException; LnZz=
~;m~)D
publicint getUserCount()throws HibernateException; W5:S+
_?Jm.nT
publicList getUserByPage(Page page)throws !0`ZK-nA6
NLb/Bja
HibernateException; D'O[0?N"g
z[qM2
} hFa\x5I5
@]*z!>1
0e8)*2S
m{Q{ qJ5>
6?}8z
q[
java代码: R|NmkqTK~(
bz H5Lc {%
2~h)'n7Mw
/*Created on 2005-7-15*/ x)#k$QU
package com.adt.dao.impl; }9P)<[>
9L:v$4{LU
import java.util.List; e~rBV+f
uK(+WA
import org.flyware.util.page.Page; & PHHacp
E_?3<)l)RI
import net.sf.hibernate.HibernateException; Q;r 0#"
import net.sf.hibernate.Query; 7F?^gMi
;
@Gm@d
import com.adt.dao.UserDAO; &$hfAG]"
:CHCVoh@95
/** XNu2G19jb
* @author Joa KU33P>a"[k
*/ .:RoD?px
public class UserDAOImpl extends BaseDAOHibernateImpl [Z
Ea3/
Bb:jy!jq_
implements UserDAO { *N'B(j/
XfbkK )d
/* (non-Javadoc) `!m+g0
* @see com.adt.dao.UserDAO#getUserByName ['-ln)96.
`34[w=Zm
(java.lang.String) W,Dr2$V
*/ i8HSYA
publicList getUserByName(String name)throws ~,':PUkiV
%I Y-0\
HibernateException { 8Qu].nKe
String querySentence = "FROM user in class [zf9UUc~
f.+e
com.adt.po.User WHERE user.name=:name"; l`$f@'k
Query query = getSession().createQuery {!oO>t
Y]8l]l 1
(querySentence); {2Gp+&
query.setParameter("name", name); _rjCwo\
return query.list(); |k
4+I
} >>^c_ 0"O
oF,8j1
/* (non-Javadoc) (:T~*7/"
* @see com.adt.dao.UserDAO#getUserCount() Kq!n`@
*/ >y]YF3?
publicint getUserCount()throws HibernateException { :X`J1E]Rjd
int count = 0; sFS_CyN!7
String querySentence = "SELECT count(*) FROM &Vgjd>
2
H^9Qd
user in class com.adt.po.User"; \UB<'~z6!
Query query = getSession().createQuery XyhOd$)
B)^]V<l(w
(querySentence); yMz@-B
count = ((Integer)query.iterate().next }3[ [ONA
bJ. ((1$
()).intValue(); R4V>_\D/
return count; +oQ@E<)H
} M5) 6|T
=:a3cr~
/* (non-Javadoc) pm )A*][s
* @see com.adt.dao.UserDAO#getUserByPage yDd&*;9%Qg
Pi*,&D>{7
(org.flyware.util.page.Page) b: %>TPT
*/ /h2`?~k+
publicList getUserByPage(Page page)throws eW >k'ez
O Zt 'ovY
HibernateException { t]vX9vv+D
String querySentence = "FROM user in class ;#xhlR* ~
$ h_ @`j
com.adt.po.User"; n }MG
Query query = getSession().createQuery ,9+@\
'w9tZO\2
(querySentence); ',1rW
query.setFirstResult(page.getBeginIndex()) xOu
cZ+
.setMaxResults(page.getEveryPage()); ,sLV6DM
return query.list(); VJr?`
eY4
} A0[flIl
yobi$mnsy!
}
2EE#60
iwmXgsRa9}
:EA,0 ,
OB$A"XGAEV
tU)+q?Mw
至此,一个完整的分页程序完成。前台的只需要调用 {n1o)MZ]R
'mmyzsQ\6
userManager.listUser(page)即可得到一个Page对象和结果集对象 o-)E_X
iSFgFJG^
的综合体,而传入的参数page对象则可以由前台传入,如果用 r2&{R!Fj`
3{$cb"5
webwork,甚至可以直接在配置文件中指定。 `pcjOM8u
6(ja5)sn*
下面给出一个webwork调用示例: .)W8
U [
java代码: J-,T^Wv
bq
~'jg^#
l_}c[bAUu
/*Created on 2005-6-17*/ c8}1-MKs_R
package com.adt.action.user; vk#xCggK
_wHqfj)
import java.util.List; 7CQ48LH]
jliKMd<?
import org.apache.commons.logging.Log; Tp0Tce/
import org.apache.commons.logging.LogFactory; 92} ,A`=
import org.flyware.util.page.Page; 14^t{
o^AK@\e:^Z
import com.adt.bo.Result; \j K?R
6
import com.adt.service.UserService; cCj}{=U
import com.opensymphony.xwork.Action; 8H{@0_M
m$O@+;>l
/** .+M4Pi
* @author Joa }QC:!e,yG
*/ /Hd\VI
publicclass ListUser implementsAction{ O~xc>
w
;CU3CLn
privatestaticfinal Log logger = LogFactory.getLog ="I]D
I
Pp.X Du
(ListUser.class); HWs?,AJNxB
(,<?Pg7v:f
private UserService userService; 8} S|iM
x&?35B
i
private Page page; Ii,L6c
ZsV'-gu
privateList users; *~-~kv4-
E&"bgwav{(
/* xwz2N5
* (non-Javadoc) &t6L8[#yd
* ^,`yt^^A
* @see com.opensymphony.xwork.Action#execute() I=lA7}
*/ *J%+zH
publicString execute()throwsException{ q&P"
Result result = userService.listUser(page); I/'jRM
page = result.getPage(); 5B@&]-'~
users = result.getContent(); B6ys5eQ
return SUCCESS; 2 K`
hH
} gWJLWL2
u/,m2N9cL
/** g/T`4"p[H
* @return Returns the page. +i
K.+B
*/ ,':?3| $c
public Page getPage(){ O"{NHNG\oT
return page; pG|DT ?
} W;hI[9
r?[Zf2&
/** Q4Cw{2r
* @return Returns the users. YgVZq\AV"
*/ Y%Saz+
publicList getUsers(){ Lo !kv*
return users; 7j@TW%FmV\
} o 0fsM;K
s3t{freM
/** )FgcNB1|7
* @param page T@f$w/15
* The page to set. G`TO[p]q
*/ L]9*^al
publicvoid setPage(Page page){ '5{gWV`
this.page = page; m@TU2
} eLl;M4d
RX#:27:
/** 3ne=7Mj
* @param users )kg^.tP
* The users to set. r_Xk:
*/ =G*<WcR
publicvoid setUsers(List users){ m}8c.OJ>K`
this.users = users; Thz&wH`W
} ,.DU)Wi?}
]V}";cm;2
/** ek3/`]V:
* @param userService 'S&5zwrH
* The userService to set. 6R"& !.ZF
*/ EXo"F*gW
publicvoid setUserService(UserService userService){ V>z8*28S.
this.userService = userService; ky[FNgQ3n
} P PmE.%_
} {:!*1L
_d,_&7
EK[~lIXg
"-\I?k
.`iOWCS
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, [_CIN
w 8T#~Dc
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 91[(K'=&
UKn>.,
么只需要: BK6oW3wD/
java代码: *\-6p0~A
joYj`K
7)<&,BWc
<?xml version="1.0"?>
NouT~K`'
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Sh=z
n{=vP`V_
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ~#OnA1)
*<]ulR2
1.0.dtd"> Fb.wm
UG 9uNgzQ/
<xwork> %nT!u!#
0<nk>o
<package name="user" extends="webwork- iCa#OQ
jIg]?4bW[
interceptors"> @2Z{en?
}eSaF@.
<!-- The default interceptor stack name CO-9-sQx
AvH^9zEE(
--> arET2(h
<default-interceptor-ref r
",..{
=`99ez+y
name="myDefaultWebStack"/> FL9Dz4
O_*%_S}F&
<action name="listUser" 3Vs8"BFjz
0.=dOz r
class="com.adt.action.user.ListUser"> N-y[2]J90
<param "V}WV!w
|!,;IoZ
name="page.everyPage">10</param> F7x]BeTM
<result /Rf:Z.L
<0T|RhbY
name="success">/user/user_list.jsp</result> 6 -N 442
</action> (gQP_Oa(
Rcc9Tx(zvQ
</package> xo
a1='
3c}@_Yn
</xwork> f;x0Ho5C2
Jx!#y A;
YZMSiDv[e
Vo"Wr>F
Nu/wjx$b
B/0Xqyu
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 =+DfIO
#p*D.We
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 DS%~'S
n
9PYZxy
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 0*]n#+=
l|9'M'a
J;|a)Nw
%68'+qz
I() =Ufs5z
我写的一个用于分页的类,用了泛型了,hoho L `NY^
aS=-9P;v
java代码: < KGq
-n FKP&P
9kHVWDf
package com.intokr.util; k<Qhw)M8
{bHUZen
import java.util.List; !K*(# [
{7'Wi$^F
/** }IEwGoDwNs
* 用于分页的类<br> =h0vdi%{
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :e/*5ix
*
h!=h0
* @version 0.01 4a}[&zm(5
* @author cheng VK286[[fv
*/ @QteC@k
public class Paginator<E> { 0v+-yEkw
privateint count = 0; // 总记录数 n&OM~Vs
privateint p = 1; // 页编号 '.EO+1{a
privateint num = 20; // 每页的记录数 %
bfe_k(
privateList<E> results = null; // 结果 d^MRu#]
'b)qP|
/** DK)T2{:
* 结果总数 v;soJlxF~
*/ hh8Grl;
publicint getCount(){ ]-8WM5\qJM
return count; o3]Lrzh
} f7YBhF
h4Wt
oE>i
publicvoid setCount(int count){ d|?Xo\+
this.count = count; UodBK7y
} !7Eodq-0
;/:Sx/#s
/** 5`Q j<
* 本结果所在的页码,从1开始 t:MSV?
* v5>A1\
* @return Returns the pageNo. wU6sU]P
*/ m<H{@ZgN(
publicint getP(){ n,U?]mr
return p; ZDg(D"
} IjGPiC
pHT]2e#
/** sYjhQN=Y*
* if(p<=0) p=1 jr,N+K(@T
* &1(- 8z*
* @param p X NgcBSD
*/ i.k7qclL`
publicvoid setP(int p){ )fHr]#v
if(p <= 0)
N=AHS
p = 1; Kv<f<>|L
this.p = p; ^M{,{bG
} JIhEkY
y];-D>jk
/**
C];P yQS
* 每页记录数量 wBcoh~
(y
*/ q3AqU?f
publicint getNum(){ s1q8r!2\w
return num; Z\?2"4H
} [Ur\^wS
9 w$m\nV
/** 'IG@JL'
* if(num<1) num=1 _0(%^5Y
*/ 1W\E`)Z}]
publicvoid setNum(int num){ m>%b4M
if(num < 1) !$A/.;0$
num = 1; 4qdoF_
this.num = num; XEQTT D<
} ;-6-DEL
|GtvgvO,
/** y{S8?$dU$:
* 获得总页数 +x(#e'6p
*/ R*:>h8
publicint getPageNum(){ [% C,&h5
return(count - 1) / num + 1; s bj/d~$N
} H T|DT
Keozn*fzI
/** 'C/yQvJ
* 获得本页的开始编号,为 (p-1)*num+1 qT48Y
*/ $c9-Q+pZ
publicint getStart(){ XEgJ7h_
return(p - 1) * num + 1; VGmvfhf#"
} 6|zhqb|s
5BJE
/** -~mgct5
* @return Returns the results. $#q`Y+;L2
*/ #L~i|(=U5
publicList<E> getResults(){ &)Xc'RQ.C
return results; Lm
TFvZ
} &^r>Q`u
OvtE)ul@
public void setResults(List<E> results){ DMM<,1
this.results = results; J0?kEr
} |M7cB$y
qx t0Jr8
public String toString(){ >>
zd
StringBuilder buff = new StringBuilder Y3Fj3NwS
}5-w,m{8/
(); nN\H'{Wzd
buff.append("{"); {%f{U"m
buff.append("count:").append(count); X` zWw_i
buff.append(",p:").append(p); gv''A"
buff.append(",nump:").append(num); q.c)>=!.
buff.append(",results:").append Y !?'[t
W6&vyOc
(results); _!nsEG
VV
buff.append("}"); q`VL i
return buff.toString(); WwDM^}e
} 3 r&
O$<>v\NC?
} :OG I|[
!cwZ*eM
7;s#QqG`I