Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $B7c\MR
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 R !yh0y}Z
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 2vU-9p {
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 -v-kFzu
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分页支持类: :,M+njcFc
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java代码: &iZt(XD
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package com.javaeye.common.util; m.!LL]]
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import java.util.List; 7VG*Wu
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publicclass PaginationSupport { ''D7Bat@
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publicfinalstaticint PAGESIZE = 30; 4f~sRubK
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privateint pageSize = PAGESIZE; wEwRW
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privateList items; 8EMBqhl
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privateint totalCount; K F_Uu
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privateint[] indexes = newint[0]; ~5h4 Gy)
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privateint startIndex = 0; ,X1M!'
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public PaginationSupport(List items, int rk4KAX_[
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totalCount){ jMCd`Q]K
setPageSize(PAGESIZE); _'17C/
setTotalCount(totalCount); lZ)6d-vK
setItems(items); xf/K+
setStartIndex(0); .AOc$Nt
} s,f2[6\ Y
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public PaginationSupport(List items, int ,9}JPv4Z
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totalCount, int startIndex){ Fx}v.A5
setPageSize(PAGESIZE); 3 !8#wn
setTotalCount(totalCount); (9ZW^flY
setItems(items); G_5{5Ar
setStartIndex(startIndex); Y0kcxpK/
} }!k?.(hpE
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public PaginationSupport(List items, int *3E3,c8{A
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totalCount, int pageSize, int startIndex){ X Db% -
setPageSize(pageSize); kTfRm^
setTotalCount(totalCount); X@}7 #Vt
setItems(items); .a :7|L#a
setStartIndex(startIndex); GM9[ 0+u;
} SP<Sv8Okj
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publicList getItems(){ <}A6 )=T
return items; N\&VJc
} 2;*G!rE&*`
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publicvoid setItems(List items){ d}fd^x/
this.items = items; Sz<:WY/(x
} 9eq)WI/
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publicint getPageSize(){ h*D -Vo
return pageSize; v;G/8>GRy
} u/wX7s
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publicvoid setPageSize(int pageSize){ xzA!,75@U
this.pageSize = pageSize; #o[n.
} xu"-Uj1
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publicint getTotalCount(){ r}e(MT:R'
return totalCount; Q?LzL(OioN
} 7VZ ^J`3
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publicvoid setTotalCount(int totalCount){ +mD;\iW]
if(totalCount > 0){ PPrvVGP
this.totalCount = totalCount; ewN|">WXQ
int count = totalCount / T"3LO[j+
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pageSize; E&z^E2
if(totalCount % pageSize > 0) FZ<6 kk4
count++; ib
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indexes = newint[count]; BR?DW~7J j
for(int i = 0; i < count; i++){ v(JjvN21
indexes = pageSize * fV7
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} "k
}else{ ;nbEV2Y<
this.totalCount = 0; e@vZg8Ie
} |}e"6e%
} uEr.LCAS
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publicint[] getIndexes(){ #P z'-lo
return indexes; CE
} `|"o\Bg<
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publicvoid setIndexes(int[] indexes){ fj(WHL
this.indexes = indexes; r/0#D+A
} 7^Us
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publicint getStartIndex(){ y
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return startIndex; k5bv57@
} h82y9($cZ
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publicvoid setStartIndex(int startIndex){ i@WO>+iB
if(totalCount <= 0) 2uY:p=DxG9
this.startIndex = 0; KYKF$@
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elseif(startIndex >= totalCount) ]v@ng8
this.startIndex = indexes }3XjP55
I
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[indexes.length - 1]; QjJlVlp
elseif(startIndex < 0) veh=^K%G |
this.startIndex = 0; xOg|<Nnl
else{ *kF/yN
this.startIndex = indexes i>G:*?a
rk,64(
[startIndex / pageSize]; ;UX9Em
} }V.fY3J-
} F$JA
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publicint getNextIndex(){ RiZ}cd
int nextIndex = getStartIndex() + hZUS#75M5
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pageSize; P&5vVA6K7
if(nextIndex >= totalCount) #q0xlF@
return getStartIndex(); #\Q)7pgi.
else XM?c*,=fu
return nextIndex; p((. (fx
} Cx(HsJ!,
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publicint getPreviousIndex(){ U'5p;j)_
int previousIndex = getStartIndex() - !{uV-c-5,
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pageSize; 1ATH$x
if(previousIndex < 0) DX3jE p2
return0; 2%fkXH<
else [vY)y\W{
return previousIndex; (lYC2i_b#
} l`0JL7
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} 5y0LkuRR:
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抽象业务类 [ CU8%%7
java代码: 1_}k)(n
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/** Wk-.dJ
* Created on 2005-7-12 \vj xCkg{
*/ =PLy^%
package com.javaeye.common.business; ;4oKF7]
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import java.io.Serializable; mn{R>
import java.util.List; Xa>c]j
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import org.hibernate.Criteria; X)9|ZF2`
import org.hibernate.HibernateException; )s 1
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import org.hibernate.Session; c1f`?i}.
import org.hibernate.criterion.DetachedCriteria; Uf[Gs/!NV
import org.hibernate.criterion.Projections; #?\|)y4i
import W$" >\A0%
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org.springframework.orm.hibernate3.HibernateCallback; E/ku VZX
import jz&= 8
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org.springframework.orm.hibernate3.support.HibernateDaoS Rg~[X5
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upport; _&@cU<bdee
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import com.javaeye.common.util.PaginationSupport; *;.:UR[i
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public abstract class AbstractManager extends /dVcNo3"
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HibernateDaoSupport { #M[Cq= 2
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privateboolean cacheQueries = false; KiNluGNt
L= <,+m[!
privateString queryCacheRegion; uC`)?f*I
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publicvoid setCacheQueries(boolean JlH5 <:#PN
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cacheQueries){ {+QQ<)l^tJ
this.cacheQueries = cacheQueries; X^0jS
} -32.g\]
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publicvoid setQueryCacheRegion(String sWLH"'Z
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queryCacheRegion){ Yg`z4U'6~
this.queryCacheRegion = 2 BwpxV8
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queryCacheRegion; MWc{7,
} _~ 7cn
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publicvoid save(finalObject entity){ 3+%L[fW`/
getHibernateTemplate().save(entity); |G-o&m"
} 'P-FeN^
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publicvoid persist(finalObject entity){ W&a<Q)o*I
getHibernateTemplate().save(entity); {D&:^f
} K:sC6|wG
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publicvoid update(finalObject entity){ a,p7l$kK
getHibernateTemplate().update(entity); !1?Nc}T0Q&
} *
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publicvoid delete(finalObject entity){ O7I|<H/gVE
getHibernateTemplate().delete(entity); r|7 hm:F)
} rw dj
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publicObject load(finalClass entity, #EU x1II
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finalSerializable id){ Ucok&)7-
return getHibernateTemplate().load 1hgmlY`
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(entity, id); Bbx.RL.V
} t)~v5vr
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publicObject get(finalClass entity, )kNyl@m
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finalSerializable id){ s|&2QG0'7
return getHibernateTemplate().get mh`VZQ@
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(entity, id); #9Dixsl*Q
} }u..m$h
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publicList findAll(finalClass entity){ K29KS)~;W
return getHibernateTemplate().find("from Ib8xvzR6I&
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" + entity.getName()); b$ )XS
} yq>3IS4O
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publicList findByNamedQuery(finalString +#y[sKa
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namedQuery){ dmD':1
return getHibernateTemplate D8Vb@5MW
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().findByNamedQuery(namedQuery); #|
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} w_i$/`i+
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publicList findByNamedQuery(finalString query, I6FglVQ6
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finalObject parameter){ (UTt_ry g
return getHibernateTemplate TNC,{sM
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().findByNamedQuery(query, parameter); fXYg %
} <%Re!y@OL
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publicList findByNamedQuery(finalString query, Si]8*>}-B
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finalObject[] parameters){ asI:J/%+2
return getHibernateTemplate 4o2C=?@(
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().findByNamedQuery(query, parameters); ghiFI<)VY
} ]7^YPFc+
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publicList find(finalString query){ pOip$Z
return getHibernateTemplate().find [0}^w[
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(query);
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} CtA0W\9w5a
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publicList find(finalString query, finalObject _D(F[p|
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parameter){ "ND 7,rQ
return getHibernateTemplate().find
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(query, parameter); @&2bLJJ+
} z6R<*$4
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public PaginationSupport findPageByCriteria 0BIH.ZV#
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(final DetachedCriteria detachedCriteria){ *, o)`
return findPageByCriteria J%_
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6?ylSQ]1
} OY6lt.t
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public PaginationSupport findPageByCriteria C=AX{sn
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(final DetachedCriteria detachedCriteria, finalint 6kKIDEX
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startIndex){ r>`65o
return findPageByCriteria
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e ?H`p"l
(detachedCriteria, PaginationSupport.PAGESIZE, w.Ft-RXA W
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startIndex); .t0Q>:}&b
} ueYZM<],
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public PaginationSupport findPageByCriteria Y9 ,KOs
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(final DetachedCriteria detachedCriteria, finalint [*#ms=Zdc
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pageSize, O6;7'
finalint startIndex){ 7WW@%4(
return(PaginationSupport) ~ FM5]<X)
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getHibernateTemplate().execute(new HibernateCallback(){ X% S?o
publicObject doInHibernate pNI=HHx
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(Session session)throws HibernateException { {cKKTDN
Criteria criteria = s&!g )
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detachedCriteria.getExecutableCriteria(session); 50Co/-)j
int totalCount = =g$%.
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((Integer) criteria.setProjection(Projections.rowCount 6<R!`N 6
ED @9,W0
()).uniqueResult()).intValue(); $AUC#<*C
criteria.setProjection _bn*B$
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(null); 4r5?C;g
List items = zN {'@B
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criteria.setFirstResult(startIndex).setMaxResults Y+syc dq
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(pageSize).list(); Y|g8xkI}XB
PaginationSupport ps = '$PiyM|V
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new PaginationSupport(items, totalCount, pageSize, Y:oL
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startIndex); : }v&TQ
return ps; diGPTV-?$
} EV z>#GC
}, true); 3Qfj=;
4
} 4WZ:zr N
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public List findAllByCriteria(final \SS1-UbL
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DetachedCriteria detachedCriteria){ sME3s-
return(List) getHibernateTemplate U`D/~KJ{Y
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().execute(new HibernateCallback(){ $uF}GP_)
publicObject doInHibernate >Q#_<IcI
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(Session session)throws HibernateException { lW1Al>dW<
Criteria criteria = Mk7,:S
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detachedCriteria.getExecutableCriteria(session); {Tl5,CAz
return criteria.list(); ?k]^?7GN
} pM=@
}, true); {A2(a7vV
} 8TZNvN4u
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public int getCountByCriteria(final Q-_&5/G
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DetachedCriteria detachedCriteria){ +ZEj(fd9
Integer count = (Integer) <T+)~&g$
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getHibernateTemplate().execute(new HibernateCallback(){ /mX/
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publicObject doInHibernate _$ ]3&P
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(Session session)throws HibernateException { Lqb9gUJ:U
Criteria criteria = Fx*iAH\e
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detachedCriteria.getExecutableCriteria(session); -uXf?sTV
return (;;%B =
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criteria.setProjection(Projections.rowCount +hI:5(_
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()).uniqueResult(); F$y3oX
} $DeHo"mg7m
}, true); 8e:J{EG~
return count.intValue(); 3,=97Si=
} /-)\$T1d
} *JDQaWzBd
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用户在web层构造查询条件detachedCriteria,和可选的 W+d=BnOa8
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 VPoA,;Y"-
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PaginationSupport的实例ps。 #$2{l,>
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ps.getItems()得到已分页好的结果集 ul$k xc=N
ps.getIndexes()得到分页索引的数组 e`9d&"
ps.getTotalCount()得到总结果数 7ESSx"^B
ps.getStartIndex()当前分页索引 F_.rLgGY
ps.getNextIndex()下一页索引 CT,P Q
ps.getPreviousIndex()上一页索引 r#r L~Rsd}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /9T.]H~
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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 3m%oXT
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一下代码重构了。 n-zAkKM
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我把原本我的做法也提供出来供大家讨论吧: ]!CMo+
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首先,为了实现分页查询,我封装了一个Page类: }huj%Pnk)
java代码: 3-x ;_
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/*Created on 2005-4-14*/ U )kl!
package org.flyware.util.page; >T84NFdz+
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/** NULew]:5
* @author Joa U'~M(9uv:
* J5dwd,FQ
*/ skr dL.5
publicclass Page { by07l5
@^P<(%p
/** imply if the page has previous page */ slUnB6@Q
privateboolean hasPrePage; M3q%(!2
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/** imply if the page has next page */ 3dO~Na`S
privateboolean hasNextPage; 4eVQO%&2
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/** the number of every page */ de7
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privateint everyPage; +4L]Z;k
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/** the total page number */ rhff8C//'
privateint totalPage; xER-TT#S
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/** the number of current page */ {Kh^)oYdd
privateint currentPage; Fnqj^5
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/** the begin index of the records by the current ~jz!jF~I
gXJtk;
query */ 2i9FzpC3
privateint beginIndex;
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/** The default constructor */ _oz1'}=
public Page(){ d1jg3{pwA
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} ":v^Y
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/** construct the page by everyPage ]S0=&x@,
* @param everyPage z}BuR*WSY{
* */ K<wg-JgA
public Page(int everyPage){ &/m0N\n?
this.everyPage = everyPage; t,NE`LC
} tJe5`L
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/** The whole constructor */ %Ev)Hk
public Page(boolean hasPrePage, boolean hasNextPage, g)!d03Qoy
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?,}:)oA_
int everyPage, int totalPage, inHlL
int currentPage, int beginIndex){ a``/x_EZMn
this.hasPrePage = hasPrePage; 5J-slNNCQ
this.hasNextPage = hasNextPage; !w1acmo<_
this.everyPage = everyPage; .R^R32ln
this.totalPage = totalPage; u+lNcyp"MW
this.currentPage = currentPage; @[LM8 @:
this.beginIndex = beginIndex; OYyF*F&S[
} C5,\DdCX,
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/** xWK0p'E0
* @return k1'd';gQ
* Returns the beginIndex. wY]ejK$0R
*/ `\beQ(g
publicint getBeginIndex(){ bblEZ%
return beginIndex; t5CJG '!ql
} .TeGA;
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/** b{BiC&3
* @param beginIndex V=gu'~
* The beginIndex to set. %MCJ%Ph
*/ &8;Fi2}(L
publicvoid setBeginIndex(int beginIndex){ /z
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this.beginIndex = beginIndex; w-];!;%
} btOx\y}
;fYJ]5>
/** :jy}V'bn$
* @return BN&eU'Dl]
* Returns the currentPage. ! FVD_8
*/ RD6>\9
publicint getCurrentPage(){ /H?) qk
return currentPage; o\<JG?P
} FM=XoMP q
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/** 5KNa-\
* @param currentPage FKtG
* The currentPage to set. Z*R~dHr
*/ H 'IxB[
publicvoid setCurrentPage(int currentPage){ naiQ$uq0
this.currentPage = currentPage; w7E#mdW
} U#x`u|L&6
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/** zh{I;~syh
* @return d};[^q6X
* Returns the everyPage. 9ec>#Vxx
*/ z57q|
publicint getEveryPage(){ $a|>>?8
return everyPage; 5g`J}@"k
} HBNX a
.?5~zet#;
/** bzaweAH
* @param everyPage &lo<sbd.
* The everyPage to set. HHerL%/
*/ CHi
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publicvoid setEveryPage(int everyPage){ 1@N4Y9o
this.everyPage = everyPage; BXNC(^
} bw)E;1zo
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/** Z6zLL
* @return [x%8l,O
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* Returns the hasNextPage. eNK6=D|
*/ y(*5qa<>
publicboolean getHasNextPage(){ x6Tpt^N}
return hasNextPage; 2uT@jfj:r
} 9e7):ZupO
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/** FzOlM-)m
* @param hasNextPage v8 II=9
* The hasNextPage to set. </B:Zjn
*/ sDvy(5
publicvoid setHasNextPage(boolean hasNextPage){ cJ>^@pd{
this.hasNextPage = hasNextPage; sC ?e%B
} sY[!=` @
Ax 4R$P.]u
/** T-\q3X|y/
* @return v+i==vxg
* Returns the hasPrePage. 9&HaEAme
*/ "u'dd3!
publicboolean getHasPrePage(){ -M+o;
return hasPrePage; /IG3>|R
} np\*r|U
#'m#Q6`
/** Pz|}[Cx-
* @param hasPrePage wH\
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* The hasPrePage to set. A9WOu*G1O
*/ &?I3xzvK
publicvoid setHasPrePage(boolean hasPrePage){ BwYR"
this.hasPrePage = hasPrePage; VrKLEN\
} MH]?:]K9V
'X\C/8\
/** DB'3h7T
* @return Returns the totalPage. 1lsg|iVz
* x}f)P
*/ KfSbm?
publicint getTotalPage(){ qL$\[(
return totalPage; !95Q4WH-@
} 3W[Ps?G
_$mS=G(
/** :4>LtfA
* @param totalPage @sRb1+nn
* The totalPage to set. ?i\$U'2*z3
*/ SwO8d;e
publicvoid setTotalPage(int totalPage){ J=H8^4M
this.totalPage = totalPage; ()fYhk|W
} ?QcS$i
IFXn GDG$
} 'h>l_A
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wh3Wuh?x
h m(
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 $wcV~'fM
9Z:pss@
个PageUtil,负责对Page对象进行构造: W,%qL6qV
java代码: zB"y^g
CbMClnF
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/*Created on 2005-4-14*/ O_D;_v6Ii+
package org.flyware.util.page; _z3^.QP
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import org.apache.commons.logging.Log; Ct0%3]<J
import org.apache.commons.logging.LogFactory; G)=+Nt\*
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/** >SS97 9
* @author Joa &qV_|f;
* ++}#pl8e
*/ LfsOGC
publicclass PageUtil { fM<g++X
,`( Qs7)Xx
privatestaticfinal Log logger = LogFactory.getLog yiczRex%rq
Zk #C!]=
(PageUtil.class); }
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/** >;X^+JH!)
* Use the origin page to create a new page 7 v(<<>
* @param page ^p~ 3H
* @param totalRecords (!<G` ;}u
* @return rgu7g
*/ B 3eNvUFZg
publicstatic Page createPage(Page page, int L_AQS9a^D
-vS7 %Fbr
totalRecords){ 2J7JEv|
return createPage(page.getEveryPage(), &wB?ks
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page.getCurrentPage(), totalRecords); j2:A@a6
} i^/D_L.
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/** WtbOm
* the basic page utils not including exception YifTC-Q;
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handler ^^( 4xHN
* @param everyPage ;hPo5uZQ
* @param currentPage GnW_^$Fs
* @param totalRecords SVT'fPm1M
* @return page }/z\%Y
*/ wk6tdY{&s
publicstatic Page createPage(int everyPage, int u=B,i#>s
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currentPage, int totalRecords){ H{*R(S<I
everyPage = getEveryPage(everyPage); ;gW?Fnry;
currentPage = getCurrentPage(currentPage); nB ,&m&
int beginIndex = getBeginIndex(everyPage, 6H!"oC&
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currentPage); @33-UP9o
int totalPage = getTotalPage(everyPage, iLkP@OYgQ
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totalRecords); d#nKTqSg
boolean hasNextPage = hasNextPage(currentPage, <k2]GI-}h
nL*
SNQ_
totalPage); 2a:JtJLl
boolean hasPrePage = hasPrePage(currentPage); f<( ysl1[
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returnnew Page(hasPrePage, hasNextPage, C AF{7 `{
everyPage, totalPage, sm @Ot~;
currentPage, n&}ILLc
#)$@Kvm
beginIndex); t>%J3S>'ZV
} '|K408i
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privatestaticint getEveryPage(int everyPage){ 4O3-PU>N
return everyPage == 0 ? 10 : everyPage; l050n9#9p
} $Z^HI
. vQCX1V(
privatestaticint getCurrentPage(int currentPage){ j*N:Kdzvl
return currentPage == 0 ? 1 : currentPage; cXvq=Rb
} $v+t~b
`}fwR
privatestaticint getBeginIndex(int everyPage, int qQUCK
38eeRo
currentPage){ +t PqU6
return(currentPage - 1) * everyPage; [0mg\n?
} Mi_/
^
\py
\rI
privatestaticint getTotalPage(int everyPage, int
m|+g_JZ
Sj<WiQ%<
totalRecords){ gEU|Bx/!=
int totalPage = 0; sYb( g'W*'
O9]+Jd4W
if(totalRecords % everyPage == 0) (lVHKg&U[
totalPage = totalRecords / everyPage; m339Y2%=
else -V)DKf"f
totalPage = totalRecords / everyPage + 1 ; -:o4|&g<*
X,h"%S<c#H
return totalPage; K PSHBv-#
} ];1Mg
m`Ver:{
privatestaticboolean hasPrePage(int currentPage){ 8z
h{?0
return currentPage == 1 ? false : true; rik0F
} $Y5m"wySZ
d%:
privatestaticboolean hasNextPage(int currentPage, /^<Uy3F[p
O
o+pi$W
int totalPage){ UMbM3m=\
return currentPage == totalPage || totalPage == L) ]|\|
mxJ& IV
0 ? false : true; qE&R.I!o
} 4R/cN'-
yk|<P\
fSFb)+
} g",htYoEnj
[~<X|_LG
|B;tv#mKD
zg2}R4h
+bw>9VmG
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。 LJAqk2k
D-tm'APq
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 %`[Oz[V
KK%R3{
做法如下: ;L458fYs
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 T!*lTzNHm
6RLYpQ$+
的信息,和一个结果集List: S3iXG
@
java代码: ZCAdCKX|
kgV_*0^
eJJD'Z
/*Created on 2005-6-13*/ rv\m0*\<
package com.adt.bo; N1 }#6YNw
;5bzXW#U
import java.util.List; $&Ntdn
V_T.#"C4=z
import org.flyware.util.page.Page; n@)Kf
A)&
zMf.
/** vO#=]J8`
* @author Joa D!-
78h
*/ dC7YVs_,#
publicclass Result { $-}a<UFE;
.W#-Cl&n8
private Page page; Oist>A$Z
S}Q/CT?au
private List content; VM1`:1Z:$
ebSG|F
/** TM1isZ
* The default constructor M6 W{mek
*/ \L"Vx9xT
public Result(){ +$-@8,F>
super(); +M"Fv9
} 2+7rLf`l
d@a FW
/** O"$uw
* The constructor using fields y\Z$8'E5W
* 5*ip}wA
* @param page #JFTD[1
* @param content 3$u3ssOL
*/ n\v;4ly^
public Result(Page page, List content){ E*!
this.page = page; p=7{
this.content = content; QU]&q`GE
} D+Ke)-/
6fozc2h@x%
/** }Ss]/_t
* @return Returns the content. xpWx6
*/ X2?
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publicList getContent(){ ZH:-.2*cj
return content; mUmU_L u8
} *v}8n95*2
x +=zG4Hm
/** 4;]<#u
* @return Returns the page. 1VlRdDg
*/ ADTx _tE
public Page getPage(){ /!l$Y?
return page; b?p <y`
} X0\2q D
-bN;nSgb
/** )"W(0M]>
* @param content Z r}5)ZR.
* The content to set. _.9):i2<SF
*/ x}Y
public void setContent(List content){ -VqZw&"
this.content = content; tai=2,'
} TN xl?5:
uANG_sX^n
/** jT~PwDSFt3
* @param page 6zmt^U
* The page to set. %V,2,NCd
*/ WF)(Q~op0U
publicvoid setPage(Page page){ G E=J Y
this.page = page; I~'%
} ,N[N;Uoj
} -YXNB[C
9Q~9C9{+
M bj{C
q#{.8H-X'
vD=>AAvG
2. 编写业务逻辑接口,并实现它(UserManager, VH.mH<
!Ez5@
UserManagerImpl) !e8OC9_x
java代码: qXOWCYqs
_JVFn=
}?KvT$s
/*Created on 2005-7-15*/ g[oa'.*OB
package com.adt.service; 9O8na
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@/MI
Oxg[
import net.sf.hibernate.HibernateException; /6=IL
+-DF3(
import org.flyware.util.page.Page; OcA_m.
|WiE`&?xP
import com.adt.bo.Result; hA6
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/** N~""Lc&
* @author Joa p?uk|C2
*/ ~4 ~c+^PF
publicinterface UserManager { TY."?` [FK
7L%JCH#F
public Result listUser(Page page)throws Nl 4,c[$C
<EhOIN7@*D
HibernateException; v r=va5
*oby(D"p
} \#
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oO0dN1/
7U9*-9
S:bYeD4
q7}r D$
java代码: Y X`BX$
^(j}'p,
)8cb @N
/*Created on 2005-7-15*/ K nl`[Nl
package com.adt.service.impl; T*Dd%
f
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import java.util.List; |rU?
CPW^pGT+i
import net.sf.hibernate.HibernateException; 2)~`.CD?L
M_I.Y1|
import org.flyware.util.page.Page; *1H8
&
import org.flyware.util.page.PageUtil; 6`PQP;
Q #Tg)5.\
import com.adt.bo.Result; (#&-ld6
import com.adt.dao.UserDAO; $ Jz(Lb{
import com.adt.exception.ObjectNotFoundException; ]C;X/8'Jf5
import com.adt.service.UserManager; x%v[(*F#y
e3#0r
/** %E R"Udh
* @author Joa a2!U9->!
*/ z4qc)-
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publicclass UserManagerImpl implements UserManager { URd0|?t9^L
H;h$k]T
private UserDAO userDAO; oe'f?IY
5}3#l/
/** HzMr
* @param userDAO The userDAO to set. 9{GEq@`7
*/ |erG cKk
publicvoid setUserDAO(UserDAO userDAO){ `hl8j\HV<}
this.userDAO = userDAO; )+ V)]dS@%
} o=nF .y
qj7}]T_
/* (non-Javadoc) W? F Q
* @see com.adt.service.UserManager#listUser [u $X.=(
dwpE(G y6c
(org.flyware.util.page.Page) RoFOjCc>D.
*/ tEN8S]X
public Result listUser(Page page)throws 0!Vza?9
aw923wEi
HibernateException, ObjectNotFoundException { ~n"?*I`
int totalRecords = userDAO.getUserCount(); O"GuVC}B
if(totalRecords == 0) Mp?Gi7o=
throw new ObjectNotFoundException :MP*Xy\7&J
w+wg)$i
("userNotExist"); 8nu@6 )#
page = PageUtil.createPage(page, totalRecords); +a'LdEp
List users = userDAO.getUserByPage(page); Ol
sX
returnnew Result(page, users); O#do\:(b
} [ *~2Ts
Tc.QzD\
} 0H+!v
:#VdFMC<
k-N}tk/5
y;if+
IAHQT<]
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {E;oirv&
ri`;
询,接下来编写UserDAO的代码: uq2C|=M-x\
3. UserDAO 和 UserDAOImpl: (KLhF
java代码: EzeU-!|W
Ygbyia|
3&!v"ms
/*Created on 2005-7-15*/ Eq?U$eE
package com.adt.dao; I/*^s
SHYbQF2
import java.util.List; LVNA`|>
nWes,K6T
import org.flyware.util.page.Page; iYf)FPET
8og8;#mnyr
import net.sf.hibernate.HibernateException; `Frr?.3&-
+lX Iv
/** TVM19)9
* @author Joa .0rTk$B
*/ 0j!xv(1
publicinterface UserDAO extends BaseDAO { A"O\u=!
K))P
2ss
publicList getUserByName(String name)throws mKqXB\<
^;9<7h[l
HibernateException; %L|xmx!c
6)PnzeYW
publicint getUserCount()throws HibernateException; vqAEF^HYry
;X
N Ahg7
publicList getUserByPage(Page page)throws rb*0YCi
wmA TV/
HibernateException; jLA)Y
[h
8(ot<3(D
} 6M
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`TYC]9
1bFGoLAEFl
?iZM.$![
java代码: l;rA}?,.^
^?2zoS#iw
!' 0PM[
/*Created on 2005-7-15*/ [C/{ ru&E
package com.adt.dao.impl; g t9(5p
#+N_wIP4
import java.util.List; Ifokg~X~G
njZJp|y6
import org.flyware.util.page.Page; \:g\?[
0CvGpM,
import net.sf.hibernate.HibernateException; B]NcY&A
import net.sf.hibernate.Query; 9q+W>wt
k 1a?yH)=
import com.adt.dao.UserDAO; Ai"MJ6)
w59q* 2
/** >& 4) :
* @author Joa Eyz.^)r
*/ )4h|7^6ji
public class UserDAOImpl extends BaseDAOHibernateImpl A.mFa1lH
@u`W(Ow
implements UserDAO { OFBEJacy
}.pqV
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/* (non-Javadoc) PhPe7^
* @see com.adt.dao.UserDAO#getUserByName cs7^#/3<
2$MoKOx8$
(java.lang.String) bIlNA )g
*/ &uF~t
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publicList getUserByName(String name)throws 1KY0hAx
5
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HibernateException { 0y t36Du
String querySentence = "FROM user in class c&P/v#U_
1V9A nzwX
com.adt.po.User WHERE user.name=:name"; S?6-I,]h
Query query = getSession().createQuery MkHkM
k<P`
(querySentence); *~YdL7f)J
query.setParameter("name", name); /CH]'u^j
return query.list(); a0+q^*\d\R
} f _$hK9I
x[$KZGK+GL
/* (non-Javadoc) a6gPJF[Jo
* @see com.adt.dao.UserDAO#getUserCount() m+(g.mvK>
*/ vQp'bRR
publicint getUserCount()throws HibernateException { _!VtM#G[
int count = 0; ~-[!>1!%
String querySentence = "SELECT count(*) FROM <;yS&8
QVJpX;u
user in class com.adt.po.User"; Q"D5D
rj
Query query = getSession().createQuery '&hd^9]Lo
d"IZt;s/,
(querySentence); O$;#GpR
count = ((Integer)query.iterate().next `d^Q!QxE
|5%T)
()).intValue(); by0K:*C
return count; w;{Q)_A
} )/vom6y*
m?4hEwQxf
/* (non-Javadoc) I]i(
B+D
* @see com.adt.dao.UserDAO#getUserByPage 7y3WV95Z\
LGW:+c
(org.flyware.util.page.Page) z?Ok'LX
*/ >e&
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publicList getUserByPage(Page page)throws 71 %$&6
;/_htdj
HibernateException { Y#Q!mbp
String querySentence = "FROM user in class [OTn>/W'
zwU[!i)
com.adt.po.User"; T9%|B9FeJ
Query query = getSession().createQuery $'>JG9M
|U;O HS
(querySentence); 8AFc=Wx
query.setFirstResult(page.getBeginIndex()) Hi=</ Wy;
.setMaxResults(page.getEveryPage());
j5Da53c#^
return query.list(); 4_iA<}>|
} 1<1+nGO
GS=E6
} x>B\2;
^\Z+Xq1~/
[T,^l#S1
eUZk|be
n[gE[kw
至此,一个完整的分页程序完成。前台的只需要调用 d{Jk:@.1
Ex
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userManager.listUser(page)即可得到一个Page对象和结果集对象 ZLxa|R7
.MG83Si
的综合体,而传入的参数page对象则可以由前台传入,如果用 I/O/*^T
Z#Kf%x.
webwork,甚至可以直接在配置文件中指定。 yc~<h/}#
O=V_7I5
下面给出一个webwork调用示例: RqGX(Iuv
java代码: +a^gC
y]+5Y.Cw$
k9OGnCW\
/*Created on 2005-6-17*/ NJ.oM E@=
package com.adt.action.user; ,8Po
_[
.l_Nf9=
import java.util.List; &K60n6q{aQ
_qf39fM;\
import org.apache.commons.logging.Log; /q\e&&e
import org.apache.commons.logging.LogFactory; ("t'XKP&N
import org.flyware.util.page.Page; ,>rvl P
{R-o8N
import com.adt.bo.Result; Nj3iZD|
import com.adt.service.UserService; u%e~a]
import com.opensymphony.xwork.Action; ZHN'j ]?
AK,'KO%{=
/** ~?Ky{jah:^
* @author Joa Z3hZy&_I
*/ P9'`
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publicclass ListUser implementsAction{ PIa!NPy
Rr%x;-
privatestaticfinal Log logger = LogFactory.getLog P'OvwA
Lu.+J]Rz
(ListUser.class); {CI4AT!?W
$'3xl2T
private UserService userService; GW;%~qH[,
"}qs+
private Page page; aH{)|?
ltgtD k
privateList users; J??AU0vh
$ch`.$wx
/* hI!BX};+}
* (non-Javadoc) eNK
+)<PK(
* .>F4s_6l
* @see com.opensymphony.xwork.Action#execute() \ m~?yq8H
*/ Zf@B<
m
publicString execute()throwsException{ 30uPDDvar
Result result = userService.listUser(page);
#O}}pF
page = result.getPage(); ;\2Z?Kq
users = result.getContent(); 4\&Y;upy+
return SUCCESS; XP?jsBE
} 0?>(H(D^/
zq{UkoME
/** I_v}}h{
* @return Returns the page. /9G72AD!
*/ Lcpe*C x-
public Page getPage(){ 9% T"W
return page; xt5/`C
} lUs$I{2_
}psRgF
/** dJ6fPB|k
* @return Returns the users. &}k7iaO
*/ &R<aRE:+R
publicList getUsers(){ @!f4>iUy
return users; 950N\Y@u
} %|(c?`2|
WsV"`ij#
/** tn'Jkwp
* @param page 2uE<mjCt-r
* The page to set. f(m,!
*/ 43AzNXWF8
publicvoid setPage(Page page){ |cma7q}p
this.page = page; OY`B{jV-
} KN|<yF
}<A.zwB<i
/** EYq?NL='
* @param users [UzD3VPg
* The users to set. NAvR^"I~
*/ !|&|%x6@
publicvoid setUsers(List users){ *tF~CG$r
this.users = users; |^1U<'oM#
} Bxm,?=h
WMa0L&C~v
/** MMFwT(l<1
* @param userService N2}SR|.
* The userService to set. H/O.h@E4X
*/ Kk8}m;
publicvoid setUserService(UserService userService){ ~U&NY7.@
this.userService = userService; AYA{_^#+3
} ,D+ydr
} [#Y
L_*p
H>EM3cFU
TBBnsj6e
SU ~a()"
INi$-Y+
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, $~G,T
g
j HHWq>=d
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 ]u_j6y!
{]R'U/
么只需要:
XA2Ld
java代码: NZq-%bE
ccuGM W G*
.c"nDCFVR
<?xml version="1.0"?> =*,SD
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K?^;|m-
'K,\
1.0//EN" "http://www.opensymphony.com/xwork/xwork- N*-tBz
{q0+PzgP
1.0.dtd"> u<BU4c/p
l/X_CM8y~
<xwork> l'+3
6
'cs(gc0
<package name="user" extends="webwork- j?.F-ar
'8X>,un
interceptors"> S 5S\zTPIf
6ZQ |L=Ytp
<!-- The default interceptor stack name G68KoM
!,Uo{@E)Y
--> M5`v^>
<default-interceptor-ref *DF3juf~
{[oNUzcd
name="myDefaultWebStack"/> ff#7}9_mh
\Z]+j@9
<action name="listUser" X8|H5Y:
`>:5[Y
class="com.adt.action.user.ListUser"> ;}46Uc#WS
<param +94)BxrY
$xbC^ k
name="page.everyPage">10</param> 9pp+<c
<result ;28d7e}
i
9)
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name="success">/user/user_list.jsp</result> 3B&A)&pEO
</action> Xul`>8y|
x%B_v^^^
</package> JmI%7bH@
7Q .Su
</xwork> \zO.#H
r<`:Q]
6R6Ub
0
$p0nq&4c
AWR :~{
2}vibDq p
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Q]k<Y
<|Td0|x
_q
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 cI=6zMB
>;fVuy
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 `fBQ?[05.
5PeS/%uT@
;,4*uU'vq
}%< ?]
-H-U8/W C
我写的一个用于分页的类,用了泛型了,hoho sl' 4AK~\
hg)Xr5>
java代码: 9z7_D_yN2
>ED;_L*_o
FOTe,F.8
package com.intokr.util; C(N'=-;Kl
%rW}x[M%w?
import java.util.List; my'nDi
8Y`Lq$u
/** F\:~^`
* 用于分页的类<br> |a(KVo
* 可以用于传递查询的结果也可以用于传送查询的参数<br> LE\*33k_
* (Z),gxt
* @version 0.01 dN{At-
* @author cheng y~9wxK
*/ O<m46mwM
public class Paginator<E> { [EAOk=X
privateint count = 0; // 总记录数
0,Ds1y^
privateint p = 1; // 页编号 bfxE}>
privateint num = 20; // 每页的记录数 5nG\J
g7
privateList<E> results = null; // 结果 7)rQf{q7
{?qfH>oFA
/** }a]`"_i;[
* 结果总数 ?WI v4
*/ /vQ)$;xf#
publicint getCount(){ V}E['fzBFV
return count; +b|F_
} k6tCfq;
=M\yh,s!
publicvoid setCount(int count){ $@AJg
this.count = count; yzS]FwW7
} *6s_7{;
{*_Ln
/** Aiq Kf=
* 本结果所在的页码,从1开始 vt
EfH
* CmU@8-1
* @return Returns the pageNo. 6#Vl3o(E|
*/ /`PYk]mJh
publicint getP(){ {wSi?;[Gq
return p; 7e<=(\(yl
} _J,**AZ~z
uo:RNokjJ
/** E?w#$HS
* if(p<=0) p=1 &CG94
* ]cRvdUGv
* @param p zEQ]5>mG
*/ ?^&ih:"
publicvoid setP(int p){ A c_P^
if(p <= 0) g\aO::
p = 1; +ai3
this.p = p; N.|F8b]v
} UylIxd
!yNU-/K
/** (hc!!:N~q
* 每页记录数量 N_%@_$3G]
*/ ,:S#gN{U
publicint getNum(){ v^9eTeFO
return num; 7[Us.V@
} 6i/unwe!`)
8eT#-9q@
/** B:zx 9
* if(num<1) num=1 rz|T2K
*/ %`Ce#b()'
publicvoid setNum(int num){ jFQ y[k-B
if(num < 1) !'$*Z(
num = 1; frcAXh9
this.num = num; gwaSgV$z
} 4MC]s~n
6~dAK3v5
/** O"\4[HE^
* 获得总页数 |!o C7!+0^
*/ PMQTcQ^
publicint getPageNum(){ <"Y>|X
return(count - 1) / num + 1; eD*764tG
} D0J{pAJ
-@AhJY.
/** `^#Rwn#
* 获得本页的开始编号,为 (p-1)*num+1 iwnGWGcuS
*/ I
Fw7?G,
publicint getStart(){ ~}OaX+!
return(p - 1) * num + 1; ;D'm=uOl
} bdrE2m
9/"&6,
/** A1zRzg4 I
* @return Returns the results. eC/{c1C
*/ k}LIMkEa4a
publicList<E> getResults(){ /KH85/s
return results; b^R:q7ea
} C:1(<1K
a`Bp^(f}
public void setResults(List<E> results){ AO<T6VK
this.results = results; or-k~1D
} $HwF:L)*
Od.@G ~
public String toString(){ +}jzge"
StringBuilder buff = new StringBuilder /`cy4<
;(K/O?nrJ
(); \J:+Wl.9A
buff.append("{"); k4#j
l<R
buff.append("count:").append(count); tMLiG4
|7
buff.append(",p:").append(p); g9C-!X-<T
buff.append(",nump:").append(num); q}i#XQU
buff.append(",results:").append V@0T&#
F6vsU:TfB
(results); WrP+n
buff.append("}"); Rd8mn'A
return buff.toString(); %LnLB
} ,DEq"VW_
.BxI~d^
} <.`i,|?MHS
9@1n:X
zd_N' :6