Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .dn#TtQv
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 xP7mP+D
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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 JH#p;7;
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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 ny0]Q@
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。 wjTW{Bg~G
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分页支持类: |+Xh ^E
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java代码: y"iK)SH
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package com.javaeye.common.util; 8g?2( MT;
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import java.util.List; 39x
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publicclass PaginationSupport { Knp}88DR^j
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publicfinalstaticint PAGESIZE = 30; QS@eqN
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privateint pageSize = PAGESIZE; 8\+XtS
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privateList items; Z^ .qX\<M
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privateint totalCount; `j'gt&
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privateint[] indexes = newint[0]; keJ-ohv)
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privateint startIndex = 0; of'H]IZ
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public PaginationSupport(List items, int [4-u{Tu
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totalCount){ g@m__
setPageSize(PAGESIZE); @2eH;?uO
setTotalCount(totalCount); /S9n!H:MT
setItems(items); &-KQ
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setStartIndex(0); {~V_6wY g
} X=VaBy4#
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public PaginationSupport(List items, int i x_a
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totalCount, int startIndex){ U8eU[|-8O/
setPageSize(PAGESIZE); &D` $YUl@
setTotalCount(totalCount); ]_hXg*?
setItems(items); s5ILl wr
setStartIndex(startIndex); F~3 &@TWi
} 5IP@_GV|
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public PaginationSupport(List items, int Bm;@}Ly=G
):V)Hrq?x
totalCount, int pageSize, int startIndex){ P9]95.j
setPageSize(pageSize); XeXK~
setTotalCount(totalCount); !/Wv\qm
setItems(items); CYNpbv
setStartIndex(startIndex); ?xt${?KP
} _mDvRFq
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publicList getItems(){ %sS7o3RW\
return items; zU#
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} KvEZbf3f
Ifj%" RI
publicvoid setItems(List items){ !<^`Sx/+
this.items = items; |RI77b:pX
} 7T?7KS
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publicint getPageSize(){ X6oY-4O
return pageSize; xKoNo^ FF
} HgRfMiC
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publicvoid setPageSize(int pageSize){ BtP*R,>
this.pageSize = pageSize; cWa>rUsF
} gC/-7/}
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publicint getTotalCount(){ ]K%D$x{+\
return totalCount; Ay\!ohIS3
} Mp^U)S+
nHB`<B
publicvoid setTotalCount(int totalCount){ yXA]E.K!
if(totalCount > 0){ Xqas[:)7+
this.totalCount = totalCount; LiD-su
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int count = totalCount / (ZEDDV2
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pageSize; u=6{P(5$j
if(totalCount % pageSize > 0) 4JjO.H
count++; h_h6@/1l
indexes = newint[count]; 0"M0tA#
for(int i = 0; i < count; i++){ 'p(I!]"uo
indexes = pageSize * /J'dG%
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i; *!+?%e{;b
} 0 }aw9g
}else{ +luW=j0V
this.totalCount = 0; "O{:jfq
} w5}2$r
} HUY1nb=
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publicint[] getIndexes(){ L QP4#7
return indexes; 6b#J!:?
} UjQi9ELoJ
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publicvoid setIndexes(int[] indexes){ #FV `*G
this.indexes = indexes; ,h$j%->U
} 3mM.#2=@>
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publicint getStartIndex(){ XWFuAE
return startIndex; ]#oqum@Yf1
} (#k2S-5
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publicvoid setStartIndex(int startIndex){ B\Y!5$
if(totalCount <= 0) gw9:1S
this.startIndex = 0; a0x/ ?)DO
elseif(startIndex >= totalCount) 6995r%
this.startIndex = indexes `=f1rXhI+1
'|N9xLm
[indexes.length - 1]; dCH(N_
elseif(startIndex < 0) Gu136XiX
this.startIndex = 0; Qws#v}xF
else{ k`Ifd:V.y
this.startIndex = indexes G!IJ#|D:~
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[startIndex / pageSize]; K.jm>]'z4;
} c{t(),nAA
} (T0%H<#+
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publicint getNextIndex(){ [-Dl ,P=
int nextIndex = getStartIndex() + t Sf`
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pageSize; 4d0<uB&v'
if(nextIndex >= totalCount) >T<"fEBI
return getStartIndex(); ua
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else &4O0}ax*Zm
return nextIndex; qjp<_aw
}
: V#W
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publicint getPreviousIndex(){ p#dpDjh
int previousIndex = getStartIndex() - ,M&[c|
tJ9i{TS
pageSize; _*Z2</5
if(previousIndex < 0) 1JoRP~mMxa
return0; #5x[Z[m
else N;6WfdA-
return previousIndex; H A(e
} Lqv5"r7eV
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} xl$#00|y
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抽象业务类 If_S_A c
java代码: nP >*0Fq
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/** h4^
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* Created on 2005-7-12 zk@KuBLL
*/ vWwnC)5
package com.javaeye.common.business; 'L2M
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import java.io.Serializable; ]S~Z8T-[
import java.util.List; Dyj5a($9"{
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import org.hibernate.Criteria; bG0t7~!{E
import org.hibernate.HibernateException; #`mo5
import org.hibernate.Session; p|M 8ww
import org.hibernate.criterion.DetachedCriteria; O9k9hRE]z
import org.hibernate.criterion.Projections; aMFUJrXo
import n(b(H`1n
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org.springframework.orm.hibernate3.HibernateCallback; wKCHG/W
import M"]~}*
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org.springframework.orm.hibernate3.support.HibernateDaoS {qCmZn5
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upport; *Ki ],>_~
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import com.javaeye.common.util.PaginationSupport; )BY\c7SG
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public abstract class AbstractManager extends 1TKOvy_
vb}; _/#?
HibernateDaoSupport { sSi1;9^o
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privateboolean cacheQueries = false; "}]1OL S V
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privateString queryCacheRegion; M ,8r{[2
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publicvoid setCacheQueries(boolean x(z[S$6Y\
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cacheQueries){ */n)_
this.cacheQueries = cacheQueries; yk9|H)-z
} .Mw'P\GtM
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publicvoid setQueryCacheRegion(String i=-zaboo
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queryCacheRegion){ 9
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this.queryCacheRegion = @#}9?>UV
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queryCacheRegion; 9/MUzt
} `av8|;
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publicvoid save(finalObject entity){ iZQwo3"8r
getHibernateTemplate().save(entity); ](vshgp2
} Z
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publicvoid persist(finalObject entity){ =/"Of
getHibernateTemplate().save(entity); \CL |=8[2
} cX@~Hk4=\
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publicvoid update(finalObject entity){ )kl| 5i
getHibernateTemplate().update(entity); >UpTMEQ
} hFP$MFab
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publicvoid delete(finalObject entity){ 50(/LV1
getHibernateTemplate().delete(entity); k`r}Gb
} :*e0Z2=
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publicObject load(finalClass entity, =V1k'XJ
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finalSerializable id){ ]YZ+/:#U7
return getHibernateTemplate().load _tL*sA>[~)
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(entity, id); ;"&^ckP
} zGu(y@o
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publicObject get(finalClass entity, %FQMB
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finalSerializable id){ O: sjf?z
return getHibernateTemplate().get KGkzE
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(entity, id); {SW104nb
} |,5b[Y"Dt
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publicList findAll(finalClass entity){ \w^iSK-
return getHibernateTemplate().find("from t-lWvxXe
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" + entity.getName()); Vf*!m~]Vqi
} y%=\E
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publicList findByNamedQuery(finalString /H@k;o
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namedQuery){ cg<10KT
return getHibernateTemplate o)cd!,h
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().findByNamedQuery(namedQuery); hyL3fkMJ,
} kYz)h
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publicList findByNamedQuery(finalString query, bP6QF1L
9">}@1k
finalObject parameter){ a|32Pn
return getHibernateTemplate ?
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().findByNamedQuery(query, parameter); 18Vtk"j
} >c\'4M8Cz
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publicList findByNamedQuery(finalString query, xg'z_W
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finalObject[] parameters){ e\ k=T}
return getHibernateTemplate t'_Hp},
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().findByNamedQuery(query, parameters); #,q w~l]
} 6/T
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publicList find(finalString query){ LS Na
return getHibernateTemplate().find AASw^A3p
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(query); f3|ttUX
} K&9|0xt
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publicList find(finalString query, finalObject s,"<+80%
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parameter){ @xmO\
return getHibernateTemplate().find -B9C2
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(query, parameter); V?
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} c\-5vw||b
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public PaginationSupport findPageByCriteria 4g b2$" !
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(final DetachedCriteria detachedCriteria){ "L|Ew#
return findPageByCriteria ,_r"=>?@
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); n%"q>
} >:Na^ +c
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public PaginationSupport findPageByCriteria efy65+~GG
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(final DetachedCriteria detachedCriteria, finalint yaMNt}y-q
6,G1:BV{K
startIndex){ wxkCmrV
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, e Pq(:ih
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startIndex); :`2<SF^0O
} A)kx,,[
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public PaginationSupport findPageByCriteria 4{(uw
@ JZ I
(final DetachedCriteria detachedCriteria, finalint ?FVX &{{V
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pageSize, C$vKRg\o
finalint startIndex){ A`TVV
return(PaginationSupport) )y\^5>p[
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getHibernateTemplate().execute(new HibernateCallback(){ od{Y`
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publicObject doInHibernate ^o_2=91
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(Session session)throws HibernateException { YFv/t=`
Criteria criteria = S 3Tp__
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detachedCriteria.getExecutableCriteria(session); .9
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int totalCount = C<?}?hhb
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((Integer) criteria.setProjection(Projections.rowCount o%i^t4J$e
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()).uniqueResult()).intValue(); -$f~V\M
criteria.setProjection 7*^-3Tt83
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(null); T1m"1Q
List items = QM2Y?."#
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criteria.setFirstResult(startIndex).setMaxResults 8>x!n/z)
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)
(pageSize).list(); "^F#oo%L
PaginationSupport ps = NeAkJG=<
1 !bODd
new PaginationSupport(items, totalCount, pageSize, Y ( x_bJ
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startIndex); %'a%ynFs
return ps; 1uZ[Ewl]
} (MY#;v\AYE
}, true); n1m[7s.[&
} F B9PIsFS
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public List findAllByCriteria(final z6ISJb
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DetachedCriteria detachedCriteria){ &)JQ6J_|\
return(List) getHibernateTemplate =.(yOUI
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().execute(new HibernateCallback(){ %@#+Xpa+
publicObject doInHibernate ^hzlR[
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(Session session)throws HibernateException { $h`(toTyF
Criteria criteria = !O6e,l
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detachedCriteria.getExecutableCriteria(session); |t+M/C0y/
return criteria.list(); g6{.C7m
} .<`i!Ls
}, true); ig<Eyr
} v".q578
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public int getCountByCriteria(final JQ=i{ 9iJ
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DetachedCriteria detachedCriteria){ eQu%TZ(x-$
Integer count = (Integer) g}"`@H(9r3
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getHibernateTemplate().execute(new HibernateCallback(){ k"D6Vyy`
publicObject doInHibernate XTEC0s"F
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(Session session)throws HibernateException { (|)`~z
Criteria criteria = 6zh<PETa03
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detachedCriteria.getExecutableCriteria(session); ZUP\)[~
return M #'br<]
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criteria.setProjection(Projections.rowCount L9Sd4L_e
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()).uniqueResult(); 0T7(c-
} !Ob
}, true); tvXoF;Yq
return count.intValue(); I$/*Pt];
} J ^gtSn^
} HM57b>6
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用户在web层构造查询条件detachedCriteria,和可选的 b~fX=!M
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 W,"|([t4.\
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PaginationSupport的实例ps。 q9fCoz
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ps.getItems()得到已分页好的结果集 56gpAc
ps.getIndexes()得到分页索引的数组 mkgGX|k;
ps.getTotalCount()得到总结果数 6hDK;J J&
ps.getStartIndex()当前分页索引 gw~%jD-2
ps.getNextIndex()下一页索引 bHVAa#
ps.getPreviousIndex()上一页索引 (uW/t1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 D`p&`]k3v
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 <i{O\K]9
+v4P9V|s
一下代码重构了。 j_N><_Jc
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我把原本我的做法也提供出来供大家讨论吧: -YM#.lQ
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首先,为了实现分页查询,我封装了一个Page类: 5tPBTS<<"L
java代码: K$OxeJP?F
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/*Created on 2005-4-14*/ -
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package org.flyware.util.page; 1Vq]4_09g1
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/** }L
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* @author Joa /2}o:vLj
* q/y4HT,x
*/ MuNM)pyxp
publicclass Page { 5`qt82Qm
P^m+SAAB
/** imply if the page has previous page */ z'@j9vT
privateboolean hasPrePage; n8<o*f&&9>
dFY]~_P472
/** imply if the page has next page */ HScj
privateboolean hasNextPage; +|}R^x`z
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/** the number of every page */ W>C!V
privateint everyPage; v*Tliw`-U
dWHl<BUm
/** the total page number */ v|5:;,I
privateint totalPage; is=sV:j:
+mRFHZG
/** the number of current page */ /H#- \r&r
privateint currentPage; 2|'v[
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/** the begin index of the records by the current YnnpgR.
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query */ >!+.M9
privateint beginIndex; xlPUum-o
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/** The default constructor */ m"Y;GzqQl
public Page(){ xml@]N*D#E
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} kPwgayz
7#n<d879e%
/** construct the page by everyPage oI=7X*B9
* @param everyPage <S~_|Y*v
* */ IOA"O9;
public Page(int everyPage){ p.KX[I
this.everyPage = everyPage; 9hAS#|vK
} mv@cGdxu
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/** The whole constructor */ xe^*\6Y
public Page(boolean hasPrePage, boolean hasNextPage, x_9<&Aj6
*8}Y0V\s
=4GJYhj
int everyPage, int totalPage, (]wi^dE
int currentPage, int beginIndex){ }.Eq_wP<
this.hasPrePage = hasPrePage; WqN=D5
this.hasNextPage = hasNextPage; =ark?<E
this.everyPage = everyPage; %M8Egr2|0
this.totalPage = totalPage; a%*l]S0z"
this.currentPage = currentPage; ~ILig}I
this.beginIndex = beginIndex; ;9r
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} Q(SVJ
@rs(`4QEh
/** R"(rL5j
* @return v-6"*EP
* Returns the beginIndex. ?f v?6r
*/ qGMM3a)Q
publicint getBeginIndex(){ ';`fMcN
return beginIndex; Ke-Q>sm2Q
} kN uDoo]z
z9:@~3k.
/** $iQ>c6
* @param beginIndex x_1JQDE
* The beginIndex to set. }*Qd]\fy
*/ tq=1C=h
publicvoid setBeginIndex(int beginIndex){ dDH+`;$.
this.beginIndex = beginIndex; F\1nc"K/(
} y7SOz'd
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/** Z4FyuWc3
* @return b ABx'E
* Returns the currentPage. fs4pAB #F
*/ Mr'}IX5
publicint getCurrentPage(){ 8?] :>
return currentPage; <B6@q4Q
} J5L P#o(V
$mm =$.
/** r`u}n
* @param currentPage rUfW0
* The currentPage to set. 3{_A zL
*/ :1u>T3L.z
publicvoid setCurrentPage(int currentPage){ ga#,42)H
this.currentPage = currentPage; tb,.f3;
} $w%oLI@kl
/^96|
/** !8&,GT
* @return J*6I@_{/U
* Returns the everyPage. E%eao$
*/ 3ojK2F(1D
publicint getEveryPage(){ 1wUZ0r1'
return everyPage; Cw?AP6f%
} xrx{8pf
-Nmf}`_
/** KsYT3
* @param everyPage A/N*Nc
* The everyPage to set. FtN1ZZ"<*
*/ Fk D
publicvoid setEveryPage(int everyPage){ vl$! To9R"
this.everyPage = everyPage; Wm:3_C +j
} "_+X#P
x
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/** zF/}s_><*
* @return [i[G" %Q
* Returns the hasNextPage. vZ
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*/ @RotJl/>
publicboolean getHasNextPage(){ O;[PEV~
return hasNextPage; BEvSX|M>x
} n? "ti
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/** dgssX9g37
* @param hasNextPage $m/-E#I#Z
* The hasNextPage to set. U[d/`
*/ FcIH<_r
publicvoid setHasNextPage(boolean hasNextPage){ &n<jpMB
this.hasNextPage = hasNextPage; |Ix6D
} x$CpUy{6
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8
/** Td[w<m+p<P
* @return r0G#BPgdR
* Returns the hasPrePage. d_J?i]AP|'
*/ iMx+y5O
publicboolean getHasPrePage(){ Y=X"YH|
return hasPrePage; MSeO#X
} wI>JOV7
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/** 1hZM))
* @param hasPrePage
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* The hasPrePage to set. xmKa8']x
*/ yG&kP:k<
publicvoid setHasPrePage(boolean hasPrePage){ S "oUE_>
this.hasPrePage = hasPrePage; <6/XE@"
} > 0 !J]gK
4\pA^%73
/** d1e'!y}R5
* @return Returns the totalPage. &o"Hb=k<
* }=A6Jv(j
*/ T.ub!,Y
publicint getTotalPage(){ :&yRvu
return totalPage; ([|5(Omd\
} +^YV>;
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/** ?y<n^`
* @param totalPage XeDU
,
* The totalPage to set. 3+A 0O%0*
*/ t)XV'J
publicvoid setTotalPage(int totalPage){ ORQGay
this.totalPage = totalPage; #!#V!^ o
} d\;M F
dMGu9k~u
} 3\=8tg p
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u
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yfTnj:Fz
n_Um)GI>
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 uNd ;;X
@<vDR">
个PageUtil,负责对Page对象进行构造: ~$r^Ur!E\
java代码: 7vr)JT=
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/*Created on 2005-4-14*/ zG_p"Z7,
package org.flyware.util.page; 'iJDWxCD
=/[ltUKs:a
import org.apache.commons.logging.Log; d^PD#&"g
import org.apache.commons.logging.LogFactory; :4|M
jn
S@x}QQ|.
/** UEzsDJu
* @author Joa C;9t">prk
* ny)]GvxI
*/ WE0}$P:
publicclass PageUtil { t#Th9G]1
98GlhogWt
privatestaticfinal Log logger = LogFactory.getLog FKC\VF
9 CB\n
(PageUtil.class); _g[-=y{Bb
'_V
#;DI
/** +IrZ
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* Use the origin page to create a new page 6Opa{]
* @param page r088aUO
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* @param totalRecords %,/lqc Fo
* @return JBz}|MD
*/ KF+mZB
publicstatic Page createPage(Page page, int uVGa(4u}
/be=u@KV
totalRecords){ l;OYUq~F
return createPage(page.getEveryPage(), K/^
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&f-hG3/M
page.getCurrentPage(), totalRecords); .oEbEs
} yYY Nu`
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/** LEZ&W;bCo
* the basic page utils not including exception /4*W DiH
S/.^7R7{f
handler KVN"XqE4
* @param everyPage [[WF0q
* @param currentPage !;v.>.lw
* @param totalRecords OUI6
ax\[
* @return page g\Ak;03n
*/ 9C/MRmv`
publicstatic Page createPage(int everyPage, int "k:=Y7Dx
F)SP aC4
currentPage, int totalRecords){ ]3ifdGk
everyPage = getEveryPage(everyPage); aE)by-'
currentPage = getCurrentPage(currentPage); T/l1qcf`wT
int beginIndex = getBeginIndex(everyPage, Lg4YED9#
/ylc*3e'4
currentPage); 9[VxskEh
int totalPage = getTotalPage(everyPage, /1d<P! H
"UG
K8x
totalRecords); &J$##B
boolean hasNextPage = hasNextPage(currentPage, (u&`Ij9
e4\dpvL
totalPage); ^2S# Uk
boolean hasPrePage = hasPrePage(currentPage); RNWX.g)b
b*EXIzQ
returnnew Page(hasPrePage, hasNextPage, r8[T&z@_
everyPage, totalPage, w2dcH4&
currentPage, C5*xQlCq}
| kXm}K
beginIndex); };b1aha G
} iidT~l
6ZOy&fd,Ty
privatestaticint getEveryPage(int everyPage){ 1$pb (OK
return everyPage == 0 ? 10 : everyPage; gl8Ib<{
} Q`ME@vz
S_b/DO
privatestaticint getCurrentPage(int currentPage){ Xj@+{uvQB
return currentPage == 0 ? 1 : currentPage; p=Y>i 'CG
} /Vww?9U;
y9 L14
privatestaticint getBeginIndex(int everyPage, int
%w
) +V
w5,Mb
currentPage){ n lGHT
return(currentPage - 1) * everyPage; ^U@~+dw
} T%IK/"N|+
]s_8A`vm
privatestaticint getTotalPage(int everyPage, int H'DVwnn>ik
,<`)>2 'o
totalRecords){ ?X9UTOx
int totalPage = 0; 4w93}t.z
Z[?mc|*x
if(totalRecords % everyPage == 0) $IX\O
totalPage = totalRecords / everyPage; O
)d[8jw"
else F #`=oM$5
totalPage = totalRecords / everyPage + 1 ; {ci.V*:"
`@Oa lg
return totalPage; + ulagE|7
} !*{q^IO9v&
-c*\o3)
privatestaticboolean hasPrePage(int currentPage){ IG ~`i I
return currentPage == 1 ? false : true; ;9a 6pz<
} `]i
[]|
%*}Y6tl '|
privatestaticboolean hasNextPage(int currentPage, "ju'UOcS/
iE].&>w
int totalPage){ F@YKFk+a
return currentPage == totalPage || totalPage == BuOgOYh9
Fhf<T`
0 ? false : true; EGVM)ur
} mtAE
?C-Towo=i
Ib=x~za@n
} }G
VX>p
I/6)3su%
N2C7[z+l`
$IQw=w7p
U/ od~29
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 fmX!6Kv
r6Aneg7
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Yk!/ow@.
0RFRbi@n(
做法如下: a_~=#]a
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 4?\:{1X=
49H+(*@v@
的信息,和一个结果集List: !69&Ld
java代码: zi@]83SS#
cVnJ^*Z
/] ^#b
/*Created on 2005-6-13*/ GL$De,V
package com.adt.bo; X{xBYZv4
#%0Bx3uM
import java.util.List; W~1~k{A
avQJPB)}Sb
import org.flyware.util.page.Page; 3?I;ovsM
Pe73g%
/** >$WQxbwM(
* @author Joa NoE*/!Sr
*/ ia @'%8
publicclass Result { (t+;O;
ZBT1Y.qA
private Page page; 46@{5)Tq
: 18KR*;p
private List content; !9Z r;K~\
DyJ.BQdk)
/** AlE8Xu9UB
* The default constructor \_V-A f{6
*/ /P|fB]p
public Result(){ Fb`a~c~s
super(); @mP]*$00
} RGKYW>$0RR
)Z 9E=%
/** 8Me:Yp_Xt
* The constructor using fields PXzsj.
* |1b_*G4|
* @param page yZr M.%V
* @param content IYn]U4P.
*/ `]Fx.)C#
public Result(Page page, List content){ ygJr=_iA9
this.page = page; JxE53ev
this.content = content; y$FW$Ka
} ,2Q o7(A
IJYL s
/** !G^L/?z3
* @return Returns the content. c#-U%qZ
*/ . o7m!
publicList getContent(){ `nM/l@
return content; o8/;;*
} 4;n6I)&.(
xsd_Uu*
/** y&}E~5O
* @return Returns the page. c\B|KhDk
*/ X[
q+619
public Page getPage(){ 3vhnwDcK
return page; "k*PA\U
} gVQjL+_W
Nkxmm/Z
/** 0"2=n.##
* @param content _vSn`
* The content to set. drzL.@h|
*/ :I -V_4b
public void setContent(List content){ .+7;)K
this.content = content; 7S/G
B
} HEA#bd\
,@1p$n
/** f Vb-$
* @param page ];.pK
* The page to set. &%})wZ+Dj
*/ Y<1QY?1sd
publicvoid setPage(Page page){ <N\v)Ug`
this.page = page; i1H\#;`$
} 3)-/`iy#
} j83p)ido
I}Nd$P)>
_ZY)M
?\C"YG69T
,'[<bP'%_
2. 编写业务逻辑接口,并实现它(UserManager, B<j'm0a>B
ono4U.C9
UserManagerImpl) PH"n{lW.T
java代码: 5>BK%`
>2bKSh
=t6z \WB
/*Created on 2005-7-15*/ ^Ge+~o?x
package com.adt.service; j'9"cE5_
i4^o59}8
import net.sf.hibernate.HibernateException; #fT*]NN
m[j70jYe
import org.flyware.util.page.Page; nX$XL=6mJ&
w"R:\@ F
import com.adt.bo.Result; D8
hr?:I9
!rqF}d
/** /~ x"wo
* @author Joa EEGy!bff
*/ ZPbpp@,
publicinterface UserManager { nstUMr6
yAoe51h?
public Result listUser(Page page)throws LpR3BP@At
`rf_7
HibernateException; Q}-~O1
dtp oU&?6s
} XC.%za8
@|Rrf*J?%
e{m2l2Tx:
2WU@*%sk"
=Zi2jL?On
java代码: Z!ha fhcX
um9_ru~
R
{-5Etv
/*Created on 2005-7-15*/ {&"N%;`Q
package com.adt.service.impl; !
u:Weoz
qUly\b 47
import java.util.List; e^.Fa59
(V4
~`i4V
import net.sf.hibernate.HibernateException; &hRvol\J
xO-+i\ ZV
import org.flyware.util.page.Page; y~)1
1]'>
import org.flyware.util.page.PageUtil; =JJL[}a|
liXdNk8
import com.adt.bo.Result; wE~V]bmtW
import com.adt.dao.UserDAO; ;qrB\j"
import com.adt.exception.ObjectNotFoundException; Dk?\)lD`
import com.adt.service.UserManager; {mAU3x
HuOIFv
/** 66fO7OJs
* @author Joa ~8lwe*lNV
*/ qi_Jywd:w
publicclass UserManagerImpl implements UserManager { &L^+BQ`O?
9uGrk^<t
private UserDAO userDAO; qAw x2fPu
fFc/
d(
/** Uw47LP
* @param userDAO The userDAO to set. St e=&^
*/ Y.*y9)#S6
publicvoid setUserDAO(UserDAO userDAO){ /iX+ R@
this.userDAO = userDAO; 0{=`on;
} ,T2G~^0
-;'1^
/* (non-Javadoc) je!-J8{
* @see com.adt.service.UserManager#listUser ^k]XEW{PG
*hw\35%P`?
(org.flyware.util.page.Page) b[`Yi1^]%g
*/ B>2tZZko
public Result listUser(Page page)throws at)~]dG
ayiu,DXx
HibernateException, ObjectNotFoundException { aoXb2 2]{
int totalRecords = userDAO.getUserCount(); %"P,1&\^
if(totalRecords == 0) 0(S"{Ov
throw new ObjectNotFoundException a[ex[TRKe
[D!jv"
("userNotExist"); 0zi~p>*nJC
page = PageUtil.createPage(page, totalRecords); qTqwPWW*
List users = userDAO.getUserByPage(page); ?Orxmxc
2
returnnew Result(page, users); ({q?d[q[
}
6q{HU]N+
Y*UA,<-
} h@[R6G|
l6d$V9A
)'~6HO8Z
9M:O0) s
PS[+~>%
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 |]c8jG\h
#Y4=J
6
询,接下来编写UserDAO的代码: O<,\^[x
3. UserDAO 和 UserDAOImpl: + ~>Aj
java代码: (Tbw3ENz
yrlf+tl
f`;j:O
/*Created on 2005-7-15*/ 8@tPm$
package com.adt.dao; bdc&1I$
s#WAR]x0x
import java.util.List; bLwAXW2K+
iB498t
import org.flyware.util.page.Page; 3J5!oF{H
'JRvP!]
import net.sf.hibernate.HibernateException; `tn{ei
D8xmE2%
/** 1 A\OC
* @author Joa H(Z88.OM
*/ MerFZd 1
publicinterface UserDAO extends BaseDAO { 4B^ZnFJ%m
u4/kR
publicList getUserByName(String name)throws {o>j6RS\
nYX@J6!
HibernateException; Ipf=ZD
;9c<K
publicint getUserCount()throws HibernateException;
&MCbYph,
1
=M ?GDc
publicList getUserByPage(Page page)throws 7BJzMlJ1Y
QC9eUYe
HibernateException; fP(d8xTx2y
m+Rv+_R
} K[!&b0O
[_Qa9e
@]ytla>d
=_:et0
d%o&+l#
java代码: <kx&w(=
* iF]n2g:
!y@6Mm
/*Created on 2005-7-15*/ CW,Wx: Y
package com.adt.dao.impl; DKBSFm{~Q
<=>=.kmGt
import java.util.List; L:i-BI`J
(EI;"N (x
import org.flyware.util.page.Page; c1E'$-
K@
6x%h6<#xh*
import net.sf.hibernate.HibernateException; |\7
ET[Xq
import net.sf.hibernate.Query; :>Ay^{vf=
L2[f]J%
import com.adt.dao.UserDAO; %@6}GmK^
jW
3c"
/** LILQ\I<<'
* @author Joa #g]vc_V
*/ `0Oh_8"
public class UserDAOImpl extends BaseDAOHibernateImpl "$2y-|
n:{qC{D-qS
implements UserDAO { r(RKwr:m
6I4oi@hZz
/* (non-Javadoc) '2[albxSc
* @see com.adt.dao.UserDAO#getUserByName O4og?h>
y9>ZwYN
(java.lang.String) ~2gG(1%At9
*/ %3ICI
publicList getUserByName(String name)throws 1f":HnLRM
3ZXQoC '
HibernateException { hMykf4
String querySentence = "FROM user in class v#U"pn|M
7G/1VeVjB
com.adt.po.User WHERE user.name=:name"; Pc
NkAo
Query query = getSession().createQuery =g|IG
[V
Y7*U:I+N
(querySentence); C<m{*C-`a
query.setParameter("name", name); V 7Ek-2M
return query.list(); iqe%=%ZR
} V4KMOYqm
V0P>YQq9s
/* (non-Javadoc) cT!\{~
* @see com.adt.dao.UserDAO#getUserCount() 5Hw~2 ?a,
*/ F*3j.lI
publicint getUserCount()throws HibernateException { p(/dBt[3k
int count = 0; JYW)uJ
String querySentence = "SELECT count(*) FROM .K p
>8qQK r\"
user in class com.adt.po.User"; paD !Z0v&
Query query = getSession().createQuery 7r~~Y%=C|
Lcg)UcB-#
(querySentence); -T[lx\}
count = ((Integer)query.iterate().next yL2o}ZbS
F)'.g d
()).intValue(); 0a-0Y&lQm
return count; y"H*%]
} \uza=e
t3&LO~Ye
/* (non-Javadoc) *fn*h[pV&
* @see com.adt.dao.UserDAO#getUserByPage Ljx(\Cm
d ysC4DS
(org.flyware.util.page.Page) 'U\<IL#U
*/ &QGdLXOn
publicList getUserByPage(Page page)throws HLV2~5Txc
!3*(N8_|#
HibernateException { [&#/]Ul'
String querySentence = "FROM user in class `CgaS#
P dhEQ}H
com.adt.po.User"; n8" .XS
Query query = getSession().createQuery >VN5`Zlw\C
S|]X'f
(querySentence);
]y1OFKYv
query.setFirstResult(page.getBeginIndex()) (4dhuT
.setMaxResults(page.getEveryPage()); TwVlg;
return query.list(); \<y#R~7s
} ?MgUY)X
2&^]k`Aj6D
} ihP|E,L=L
(?(zH3
=Q+=
f
`O[};3O&
=1 Oj*x@*4
至此,一个完整的分页程序完成。前台的只需要调用 eFL=G%
/oR<A
userManager.listUser(page)即可得到一个Page对象和结果集对象 %0,#ADCqOe
R}4So1
的综合体,而传入的参数page对象则可以由前台传入,如果用 2IKnhBSV3
d+Ek%_
webwork,甚至可以直接在配置文件中指定。 T^~5n6
JAQb{KefdO
下面给出一个webwork调用示例: @M5#S7q";
java代码: 9+{G8$Ai
S=e{MI
O"c;|zCc>
/*Created on 2005-6-17*/ y6[If cN
package com.adt.action.user; "F.;Dv9V[0
.R./0Ot tx
import java.util.List; v,4pp@8rv
<F`>,Pm
import org.apache.commons.logging.Log; G}:lzOlMH
import org.apache.commons.logging.LogFactory; m6[0Kws&
import org.flyware.util.page.Page; Od%"B\
[N#,K02mk
import com.adt.bo.Result; 49dd5ddr
import com.adt.service.UserService; b#hDHSdZ,
import com.opensymphony.xwork.Action; lMg+R<$~I
i5K[>5
/** F=a<~EpZ
* @author Joa }A7j/uy}s
*/ bS"fkf9
publicclass ListUser implementsAction{ Htgx`N|
p|&Yku=
privatestaticfinal Log logger = LogFactory.getLog /5:bvg+
7[5.> h
(ListUser.class); }7
c[Q($K
\V*xWS
private UserService userService; b+&%1C
|qmu_x\
private Page page; gm[z[~X@
i* NH'o/
privateList users; Y[K*57fs
8=Z9T<K
/* /|eA9 ]
* (non-Javadoc) jg\Z;_!W
* Bb}fj28
* @see com.opensymphony.xwork.Action#execute() HFaj-~b
*/ "huFA|`
publicString execute()throwsException{ dK2p7xo
Result result = userService.listUser(page); 5&q8g;XiEM
page = result.getPage(); B3
5E8/
users = result.getContent(); m/y2WlcRx
return SUCCESS; 8'4S8DM
} }` ! =
m
JAX*hGhkh
/** A?t%e
* @return Returns the page. x*nSHb
*/ ,}))u0q+:
public Page getPage(){ 5yiK+-iTs
return page; OSf}Q=BL
} *Ie7{EhJ'
<c,u3cp
/** (m:Zk$
* @return Returns the users. x"{'&J[hx
*/ Hqn#yInA7~
publicList getUsers(){ \,7}mdQSv
return users; Tny%7xSx1
} _Gjk;|Sx<I
66I"=:
/** ?}a;}Q6
* @param page 45MLt5^|
* The page to set. *?Kr*]dnLl
*/ ;F~LqC$
publicvoid setPage(Page page){ K/3)g9Z&io
this.page = page; 3T}izG]
} }woo%N P
mA*AeP_$
/** eZdu2.;<
* @param users S!3S4:]B^
* The users to set. NZ-\h
*/ c(n&A~*AJ%
publicvoid setUsers(List users){ isZA oYVu
this.users = users; 'toa@5
} nx^]>w
Qe}`~a9P
/** Xp8]qH|K
* @param userService DJ(q
7W
* The userService to set. <B6&I$Wc+
*/ 43Qtj$F
publicvoid setUserService(UserService userService){ KB'qRnkc
this.userService = userService; ]jaQ[g$F
} P3nb2.
} q&/Yg,p\
NNE<L;u
:SGF45>B@
YJ;j x0
Eg2[k.{P
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, MF'$~gxo
t$xY #:
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ghX|3lI\q
0DmMG
么只需要: (h5'9r
java代码: 8rMX9qTO@
I>[RqG
!2'jrJGc
<?xml version="1.0"?> L?Qg#YSd~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork (
|PAx(
7"w2$*4 '0
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 3`B6w$z>(
L.2/*H#
1.0.dtd"> ""1^k2fj
CFqJ/''
<xwork> p Wt)
A
;+<&8.=,)
<package name="user" extends="webwork- 7_mw%|m6@
=RAh|e
interceptors"> f3H ed
G-He" 4& $
<!-- The default interceptor stack name OV%Q3$15
'6xQT-sUih
--> i 4%xfN
<default-interceptor-ref ,>:;#2+og
#L{OV)a<
name="myDefaultWebStack"/> 3'c0#h@VD
GA?87N
<action name="listUser" H*Kj3NgY
D!.+Y-+Xzu
class="com.adt.action.user.ListUser"> P~G 1EK|4
<param -#2)?NkeE
_jNj-)RB_
name="page.everyPage">10</param> v}tag#f5>?
<result _=NwQu\_F
E2"q3_,,
name="success">/user/user_list.jsp</result> fVt9X*xKS
</action> Qum9A
:L1dyVA{
</package> Q`rF&)Q5
VGceD$<
</xwork> &s$(g~ 4gC
.GsO.#p{
C!R1})_^
dd\n8f
O=$~O\}b
9$Xu,y
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 2Ri{bWi
P#_sg0oJF
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 9(5OeH6o?
F6K4#t+9
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 r; xLP
{.De4]ANh
E/09hD Q
"bm
PC[c/CoD
我写的一个用于分页的类,用了泛型了,hoho B';6r4I-
A%^w^f
java代码: >j'ZPwj^
w7FW^6Zl
Pp|*J^U 4
package com.intokr.util; ;Wl+zw
-,+q#F
import java.util.List; CWNx4)ZGw
qWx][D"
/** ~-dV^SO
* 用于分页的类<br> &3$z4df
* 可以用于传递查询的结果也可以用于传送查询的参数<br> >zhO7,=,
* m<w"T7
* @version 0.01 Ojt`^r !V
* @author cheng <6fv1d+v
*/ * 0|IXGr
public class Paginator<E> { >9f%@uSM$3
privateint count = 0; // 总记录数 }j^\(2
privateint p = 1; // 页编号 jWY$5Vq<H
privateint num = 20; // 每页的记录数 ?APeR,"V
privateList<E> results = null; // 结果 !O#dV1wAa
{fEwA8Ir
/** H.WE6
* 结果总数 #Ap;_XcKw
*/ <7n4_RlF!
publicint getCount(){ qpsvi.S
return count; a?6ab+7#
} qKE:3g35
Qed.4R:o
publicvoid setCount(int count){ 4mHvgnT!WA
this.count = count; gt ";2,;X
} hTEx]# (
m@Qt.4m%g
/** y8 KX<2s1
* 本结果所在的页码,从1开始 r.T<j.\
* +]|Z%;im
* @return Returns the pageNo. ;]w<&C!=
*/ Udc=,yo3Qm
publicint getP(){ 1|?05<8
return p; oXDN+4ge
} J%jB?2
1:o
~j#]tElb
/** :T._ba3|
* if(p<=0) p=1 v\,N 5
* N,f4*PQ
* @param p A^RR@D
*/ g(Io/hyj
publicvoid setP(int p){ #!$GH_
if(p <= 0) =Me5ftw
p = 1; sj8~?O
this.p = p; PI~1GyJr@;
} [b/k3&O'
k $fGom
/** ?0
m\(#
* 每页记录数量 x+h~gckLb
*/ 1$2D O
publicint getNum(){ t2V0lyeL
return num; [tH-D$V
} A5+rd{k/
JGFt0He]
/** Z1h]
* if(num<1) num=1 je6CDF qw
*/ >rP#ukr5
publicvoid setNum(int num){ X!j{o
if(num < 1) T /mI[*1xI
num = 1; \(Pohw WWo
this.num = num; L3p`
} NziZTU}
$Y9jrR'w
/** -\y-qHgb/
* 获得总页数 +*n-<x5"
*/ )m&U#S _;
publicint getPageNum(){ =L5GhA~
return(count - 1) / num + 1; p)=~% 7DV
} YqV8D&I
AWjm~D-?
/** $XU5??8
* 获得本页的开始编号,为 (p-1)*num+1 "iM~Hy
*/ K9kUS
publicint getStart(){ NB7Y{)
w
return(p - 1) * num + 1; Lqp8yVO
} S#b-awk
QnI.zq
V
/** >?]_<:
* @return Returns the results. `Bw9O%]-S
*/ enTW0U}
publicList<E> getResults(){ 5PIZh<
return results; ]u-02g
} j6,ZEm
IF +i3#$
public void setResults(List<E> results){ 6ATtW+sN ]
this.results = results; #-Z8Z
i"44
} ?,=f\Fz!
ycJg%]F*5
public String toString(){ tj*y)28-
StringBuilder buff = new StringBuilder /?6gdN
]O
TH"*j
(); E_1="&p
buff.append("{"); IhiGP
{
buff.append("count:").append(count); BYM3jXWi0v
buff.append(",p:").append(p); #Ch;0UvFF
buff.append(",nump:").append(num); 3:5DL!Sm8J
buff.append(",results:").append ow/57P
XYH|;P6K
(results); CN2_bz
buff.append("}"); P0i V<T4^
return buff.toString(); o]LRzI
} /EMJSr
"{E qhR~
} vZ#!uU^a:
Pz_NDI
tQ~W EC