Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 4h!f/aF'
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1aVa0q<
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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 [XRCLi}
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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 QVF]Ci_=
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分页支持类: !UOCJj.cA
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java代码: kg][qn|>J]
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package com.javaeye.common.util; &
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import java.util.List; ^JZ^>E~
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publicclass PaginationSupport { 9YsR~SM
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publicfinalstaticint PAGESIZE = 30; nVu&/
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privateint pageSize = PAGESIZE; Q$obOEr2(
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privateList items; x:vu'A
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privateint totalCount;
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privateint[] indexes = newint[0]; GU't%[
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privateint startIndex = 0; 9jN)I(^D6
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public PaginationSupport(List items, int $Y=T&O
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totalCount){ -U<Upn)2
setPageSize(PAGESIZE); e{;OSk`x
setTotalCount(totalCount); |9"p|6G?B
setItems(items); 7&`}~$>}>e
setStartIndex(0); +,:du*C
} c`lJu_
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public PaginationSupport(List items, int t
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totalCount, int startIndex){ y@j,a
setPageSize(PAGESIZE); ) xbO6V
setTotalCount(totalCount); Tu{h<Zy
setItems(items); )!g{Sbl
setStartIndex(startIndex); EFpIp4_Y
} #-3=o6DCK
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public PaginationSupport(List items, int J};z85B
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totalCount, int pageSize, int startIndex){ -p-B2?)A
setPageSize(pageSize); `X,yM-(
setTotalCount(totalCount); rC:?l(8ng3
setItems(items); L,d
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setStartIndex(startIndex); TI9UXa:V\
} w ;daC(:
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publicList getItems(){ c4_`Ew^k
return items; TF2>4 p
} kc7lc|'z
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publicvoid setItems(List items){ b}T6v
this.items = items; zkTp`>9R
} |IunpZV
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publicint getPageSize(){ <
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return pageSize; IHgeQ F
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} *lef=:&,,
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publicvoid setPageSize(int pageSize){ b{fQ|QD{^E
this.pageSize = pageSize; @fuM)B1"
}
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publicint getTotalCount(){ V\V)<BARe
return totalCount; \4"S7.% |
} `@i5i((
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publicvoid setTotalCount(int totalCount){ -XRn~=5
if(totalCount > 0){ 3nY1[,
this.totalCount = totalCount; }HE6aF62O
int count = totalCount / sC[yI Up
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pageSize; Bl9jkq
]
if(totalCount % pageSize > 0) tBTTCwNT%
count++; 2_Wg!bq
indexes = newint[count]; 64-#}3zL
for(int i = 0; i < count; i++){ xEuN
indexes = pageSize * T#pk]c6Q
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i; DK0.R]&4(
} 7bxA]s{m
}else{ \A`hj~
this.totalCount = 0; JT
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} <p;k)S2J
} mDh1>>K'~
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publicint[] getIndexes(){ R),zl_d_
return indexes; .1 %T
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} C"lJl k9g^
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publicvoid setIndexes(int[] indexes){ `OymAyEYQ
this.indexes = indexes; ~}K5#<
} 8q`$y$06Dk
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publicint getStartIndex(){ 8 6f2'o+
return startIndex; CF|]e:
} GE|+fYVM-$
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publicvoid setStartIndex(int startIndex){ UD~p'^.m_
if(totalCount <= 0) s4_/&h
this.startIndex = 0; ?PTk1sB
elseif(startIndex >= totalCount) 3]-_q"Co4f
this.startIndex = indexes `nUO l
rbT)=-(
[indexes.length - 1]; p;?*}xa
elseif(startIndex < 0) S4witIK5
this.startIndex = 0; jlFk@:y4
else{ VF&Z%O3n
this.startIndex = indexes ]pEV}@7
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[startIndex / pageSize]; Kb =@ =Xta
} Z ,^9Z
} 2iu_pjj
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publicint getNextIndex(){ b;|55Y
int nextIndex = getStartIndex() + KYJjwXT28W
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pageSize; fjnT e
if(nextIndex >= totalCount) `[zQf
return getStartIndex(); XPB9~::
else :|o<SZ
return nextIndex; kP xa7
} #k3t3az2{
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publicint getPreviousIndex(){ "^I
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int previousIndex = getStartIndex() - Nr2 C@FU:0
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pageSize; zo;^m|
if(previousIndex < 0) J8y0d1SG
return0; \,!QJp4
else \.XLcz
return previousIndex; 2cu#lMq
} HE<1v@jW
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} Ld^GV
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抽象业务类 JO14KY*%
java代码: W&h[p_0
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/** Qr#1 u
* Created on 2005-7-12 k7tYa;C
*/ .^)UO
package com.javaeye.common.business; 2!N8rHRt
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import java.io.Serializable; Oo?,fw
import java.util.List; y {q*s8NY
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import org.hibernate.Criteria; jQU"Ved
import org.hibernate.HibernateException; !?
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import org.hibernate.Session; P?BGBbC
import org.hibernate.criterion.DetachedCriteria; {f9{8-W<u
import org.hibernate.criterion.Projections; 0oy-os
import W:i?t8y\y
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org.springframework.orm.hibernate3.HibernateCallback; ThW,Y"
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import @1zQce>
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org.springframework.orm.hibernate3.support.HibernateDaoS ck#"*],
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upport; TEUY3z[g
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import com.javaeye.common.util.PaginationSupport; U=bEA1*@0
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public abstract class AbstractManager extends TG
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HibernateDaoSupport { v+6@cC
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privateboolean cacheQueries = false; 0"pVT%b
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privateString queryCacheRegion; OPpjuIRv
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publicvoid setCacheQueries(boolean nZR!*$}A
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cacheQueries){ GC8}X;((Y
this.cacheQueries = cacheQueries; y(
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} r%Rs0)$yj
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publicvoid setQueryCacheRegion(String `ir3YnT+
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queryCacheRegion){ y0v]N
this.queryCacheRegion = Oc9#e+_&
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queryCacheRegion; -6Tk<W
} @|bP+8oU
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publicvoid save(finalObject entity){ 0f ER*.F
getHibernateTemplate().save(entity); F{k+7Ftc
} Dj-s5pAW
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publicvoid persist(finalObject entity){ ,]R8(bD)
getHibernateTemplate().save(entity); fYebB7Pv
} eT"Uxhs-}
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publicvoid update(finalObject entity){ 4n
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getHibernateTemplate().update(entity); x}fn'iUnm
} OLq
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publicvoid delete(finalObject entity){ 4{9d#[KW
getHibernateTemplate().delete(entity); >5~7u\#9
} ]TO/kl/
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publicObject load(finalClass entity, 8YY|;\F)J~
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finalSerializable id){ Al)$An-
return getHibernateTemplate().load TOl}U
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(entity, id); #nyv+x;
} j{#Wn
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publicObject get(finalClass entity, =4C}{IL
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finalSerializable id){
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return getHibernateTemplate().get tP
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(entity, id); f<[jwhCWV
} i~=s^8n`l
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publicList findAll(finalClass entity){ jStmS2n
return getHibernateTemplate().find("from kD~uGA
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" + entity.getName()); [2$4| ;7
} ZIxRyo-i
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publicList findByNamedQuery(finalString r$)$n&j
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namedQuery){ lXrD!1F
return getHibernateTemplate T!q_/[i~7
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().findByNamedQuery(namedQuery); <MD;@_Nz\
} ru.5fQU
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publicList findByNamedQuery(finalString query, NlR"$
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finalObject parameter){ )jW(6
return getHibernateTemplate /dHs &SU,
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().findByNamedQuery(query, parameter); #*IVlchA"B
} O?K./So&
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publicList findByNamedQuery(finalString query, u,i]a#K
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finalObject[] parameters){ .{dE}2^
return getHibernateTemplate ol!86rky
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().findByNamedQuery(query, parameters); <Q`&o@I
} 9$WJ"]
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publicList find(finalString query){ +Takde%~
return getHibernateTemplate().find #0y<a:}R
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(query); p]LnE`v
} )y50Mb0+
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publicList find(finalString query, finalObject G\Hq/4
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parameter){ (}H ,ng'4
return getHibernateTemplate().find @h-T:$
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(query, parameter); u]vPy
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} k'13f,o}
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public PaginationSupport findPageByCriteria swr"k6;G
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(final DetachedCriteria detachedCriteria){ ")\aJ8
return findPageByCriteria W}gVIfe
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~Yk"Hos
} +mWjBY
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public PaginationSupport findPageByCriteria 7c1+t_ Ew
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(final DetachedCriteria detachedCriteria, finalint G\rj?%
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startIndex){ ;w6s<a@Zh
return findPageByCriteria d.}}s$Q
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(detachedCriteria, PaginationSupport.PAGESIZE, Lt<oi8'N
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startIndex); |'w^ n
} 7>je6*(K
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public PaginationSupport findPageByCriteria c cr" ep
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(final DetachedCriteria detachedCriteria, finalint pcpxe&S
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pageSize, `!Ln|_,d
finalint startIndex){ Y^eX@dEFR
return(PaginationSupport) u~Lu<3v
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getHibernateTemplate().execute(new HibernateCallback(){ x70N8TQ_gK
publicObject doInHibernate -uR{X G. D
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(Session session)throws HibernateException { NG-`ag`s
Criteria criteria = YRa4W.&Yn
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detachedCriteria.getExecutableCriteria(session); 2]Fu
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int totalCount = 6Kht:WE
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((Integer) criteria.setProjection(Projections.rowCount =YoTyq\
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()).uniqueResult()).intValue(); g\J)= ,ju,
criteria.setProjection )+B=z}:Nfz
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(null); W:B }u\)C
List items = =
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( -2R{!A
criteria.setFirstResult(startIndex).setMaxResults }:^X X0:FK
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(pageSize).list(); sA2o2~AmM
PaginationSupport ps = jEE_D +K
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new PaginationSupport(items, totalCount, pageSize, bw;iz,Z
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startIndex); A:xb!=
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return ps; It\BbG=
} -d_ 7*>m$
}, true); &Q+]t"OA!
} w%~qB5wF6
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public List findAllByCriteria(final ;qG1r@o
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DetachedCriteria detachedCriteria){ ahoh9iJ
return(List) getHibernateTemplate cUVTRWV
}wG|%Y#+r
().execute(new HibernateCallback(){ "S|(4BUJ(
publicObject doInHibernate
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(Session session)throws HibernateException { ;>/ipnx
Criteria criteria = /MqP[*L
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detachedCriteria.getExecutableCriteria(session); +DxifXtB
return criteria.list(); *vXDuhQ
} }{#7Z8
}, true); <tU
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} C &FN#B
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public int getCountByCriteria(final A ')(SGSc
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DetachedCriteria detachedCriteria){ Nq
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Integer count = (Integer) 6BHPzv+Y
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getHibernateTemplate().execute(new HibernateCallback(){ gm}C\q9
publicObject doInHibernate FBbm4NB
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(Session session)throws HibernateException { B~BUWWMfp
Criteria criteria = .yG8B:7N2
{;;eOxOP|
detachedCriteria.getExecutableCriteria(session); \hu':@}
return 8}J(c=4Gk
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criteria.setProjection(Projections.rowCount ?^ eJ:
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()).uniqueResult(); w[M5M2CF
} Hq79/wKj
}, true); LP8o7%sv!
return count.intValue(); p0?o<AA%O
} >Ziy1Dp
}
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用户在web层构造查询条件detachedCriteria,和可选的 @ >
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $kM'
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PaginationSupport的实例ps。 &~42T}GTWG
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ps.getItems()得到已分页好的结果集 (PyTq
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ps.getIndexes()得到分页索引的数组 HI7]%<L
ps.getTotalCount()得到总结果数 6@i|Kw(:
ps.getStartIndex()当前分页索引 SG1&a:c+.
ps.getNextIndex()下一页索引 es{cn=\s
ps.getPreviousIndex()上一页索引 <)=3XEcb
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 p`pg5R
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Bi$
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一下代码重构了。 Q>##hG:m
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我把原本我的做法也提供出来供大家讨论吧: t*5z1T?
@G7w(>_T3
首先,为了实现分页查询,我封装了一个Page类: QZ6[*_Z6
java代码: Ax :3}
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/*Created on 2005-4-14*/ s0_-1VU
package org.flyware.util.page; ab8oMi`z
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/** Q@ykQ
* @author Joa L?AM&w-cg9
* -ryDsq
*/ Tyg$`\#
publicclass Page { /h1dm,
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/** imply if the page has previous page */ +e&m#d
privateboolean hasPrePage; ~W]#9&yQ
\ 9[NH/.Z{
/** imply if the page has next page */ HTR "mQ
privateboolean hasNextPage; /8 e2dw:
\
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/** the number of every page */ OHx,*}N
privateint everyPage; /&S~+~]n
r\4*\
/** the total page number */ OL,/-;z6
privateint totalPage; $]Q*E4(kV9
YlZYS'_
/** the number of current page */ 7F>gj
privateint currentPage; H9oXZSm
2GHXn:V
/** the begin index of the records by the current /k4^&
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query */ 34/]m/2NZK
privateint beginIndex; lBizC5t!o
(= S"Kvb~#
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/** The default constructor */ z v L>(R
public Page(){ 1 2%z3/i
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} ~`nm<
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/** construct the page by everyPage tdMP,0u
* @param everyPage ,yB?~
* */ "ZA$"^
public Page(int everyPage){ B,BOzpb(
this.everyPage = everyPage; 9 AQ96
} E|F!S(.:,M
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/** The whole constructor */ J};u25:}
public Page(boolean hasPrePage, boolean hasNextPage, A{DIp+
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int everyPage, int totalPage, lOWB^uS%
int currentPage, int beginIndex){ 9^#zxmH)
this.hasPrePage = hasPrePage; pXpLL_
this.hasNextPage = hasNextPage; XwKZv0ub
this.everyPage = everyPage; kuKnJWv
this.totalPage = totalPage; 5WtQwN~
this.currentPage = currentPage; (R;)
9I\
this.beginIndex = beginIndex; 1)P<cNj
} CYTuj>Ww
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/** N+C%Z[gt[
* @return >Rl0%!
* Returns the beginIndex. O]$*EiO\
*/ 6ywnyh
publicint getBeginIndex(){ onWYT} c{
return beginIndex; pAUfG^v
} +[X.-,yW
,N))=/
/** Y1yvI
* @param beginIndex $~w@0Yl
* The beginIndex to set. 34+)-\ xt:
*/ VrnK)za*H
publicvoid setBeginIndex(int beginIndex){ )$9C` d[
this.beginIndex = beginIndex; ecSdU>
} .Y^d9.
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/** k
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* @return }e/[$!35
* Returns the currentPage. vJ'yz#tl9
*/ 4cErk)F4
publicint getCurrentPage(){ Yq)YS]
return currentPage; m&8U4uHN
} [#,X$O>
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/** +aXk^+~j
* @param currentPage l7D4`i<F
* The currentPage to set. j"D0nG,
*/ Mi%1+
publicvoid setCurrentPage(int currentPage){ mhJOR'2
this.currentPage = currentPage; k?|F0e_
} k #,Gfs
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/** w/^0tZ~
* @return SS45<!iy
* Returns the everyPage. &Gy'AUz-
*/ sa0^1$(<
publicint getEveryPage(){ Rrs`h `'-
return everyPage; r=P$iG'&
} 9`gGsC
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/** @6I[{{>X
* @param everyPage Jq?^8y
* The everyPage to set. 2'O!~8U
*/ yaYIgG
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; UtGd/\:
} n/-p;#R
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/** ./BP+\)lO
* @return (X`t"*y"
* Returns the hasNextPage. [pC-{~
*/ pYi=q
publicboolean getHasNextPage(){ }HA2ce\
return hasNextPage; 43orR !.Z
} aP6%OI
gS(: c.
/** 9q0,K" x)
* @param hasNextPage -SC2Zgi)A
* The hasNextPage to set. 1 [~|
*/ x1hs19s
publicvoid setHasNextPage(boolean hasNextPage){ QF.wtMGF&
this.hasNextPage = hasNextPage; CgT QGJ}-
} )8N)Z~h
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/** v_1JH<GJ-
* @return b#\kZ/W
* Returns the hasPrePage. -~Z@,
*/ 9T0wdK]
publicboolean getHasPrePage(){ J1y2Qw$G
return hasPrePage; 9OJ\n|,(
} y
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/** I!0 $%
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* @param hasPrePage yQA"T?
* The hasPrePage to set. enD C#
*/ DRBYH(
publicvoid setHasPrePage(boolean hasPrePage){ i]^*J1a
this.hasPrePage = hasPrePage; :R|2z`b!
} r<f-v_bxF
~E:/oV:4 >
/** i7w}`vs
* @return Returns the totalPage. n4d(`
* ~BYEeUo;%v
*/ 3z/O`z
publicint getTotalPage(){ ?'$.
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return totalPage; N(({2'Rr
} r{:la56Xd
I}Gl*@K&O
/** )*L?PT
* @param totalPage cX=b q_
* The totalPage to set. Dil4ut-$
*/ HjF'~n
publicvoid setTotalPage(int totalPage){ NYV0<z@M2M
this.totalPage = totalPage; GL0' :LsZ
} { G>+.
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} iNrmhiql
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 z )}wo3
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个PageUtil,负责对Page对象进行构造: $MVeMgPa
java代码: PQ!?gj
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/*Created on 2005-4-14*/ 1MzB?[gx
package org.flyware.util.page; eEds-&_
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import org.apache.commons.logging.Log; "e};?|y
import org.apache.commons.logging.LogFactory; '`A67bdq)
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/** 0PX@E-n
* @author Joa 1ZH8/1gWI
* x: wq"X
*/ ?B31t9
publicclass PageUtil { YwTtI ID%
UtW3KvJ#=
privatestaticfinal Log logger = LogFactory.getLog +wgUs*(W
Fe>#}-`
(PageUtil.class); O!cO/]<
"lj:bxM2C
/** =81Xt1,
* Use the origin page to create a new page `fE:5y
* @param page `];[T=
* @param totalRecords 9(Xch2tpO!
* @return Fl(ZKpSZU
*/ |P?B AWYeQ
publicstatic Page createPage(Page page, int -`<N,
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totalRecords){ Dg4^
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return createPage(page.getEveryPage(), v?' k)B
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page.getCurrentPage(), totalRecords); ,T>2zSk
} -Y,Ibq
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/** [~H`9Ab=
* the basic page utils not including exception 3mn-dKe((
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handler ov.rHVeI
* @param everyPage L7'X7WYf&
* @param currentPage 46JP1
* @param totalRecords 20xGj?M
* @return page x-k/rZ
*/ <5L` d}
publicstatic Page createPage(int everyPage, int @)B5^[4(;
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currentPage, int totalRecords){ R_&V.\e_
everyPage = getEveryPage(everyPage); IZ ha* 7
currentPage = getCurrentPage(currentPage); T{2//$T?
int beginIndex = getBeginIndex(everyPage, jtC ob'n8
VFp)`+8
currentPage); RR {9
int totalPage = getTotalPage(everyPage, 2MrR|hLx
"tbBbEj?d
totalRecords); \DdVMn
boolean hasNextPage = hasNextPage(currentPage, 3gXUfv2ID
#3jZ7RqzQ
totalPage); HUX+d4sg
boolean hasPrePage = hasPrePage(currentPage); H zK=UcD
[-}%B0S**
returnnew Page(hasPrePage, hasNextPage, <1K:
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everyPage, totalPage, ol>=tk 8}
currentPage, 9GOyVKUv
!: [`
V!{
beginIndex); wY)GX
} nr6[rq
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privatestaticint getEveryPage(int everyPage){ PU\q.y0R
return everyPage == 0 ? 10 : everyPage; rMx_ <tX X
} AYtcN4\/
U}5KAi 9Z
privatestaticint getCurrentPage(int currentPage){ |-?b)yuAz
return currentPage == 0 ? 1 : currentPage;
c'4 \F9
} a .Vs>1
ITOGD
privatestaticint getBeginIndex(int everyPage, int ? 7dDQI7^(
RLr-xg$K-t
currentPage){ dz DssAHy
return(currentPage - 1) * everyPage; .j,&/y&
} >@\-m
2 z l
privatestaticint getTotalPage(int everyPage, int 7}?z=LHb3
s7gf7E#Y
totalRecords){ LD"}$vfs
int totalPage = 0; g[Y$SgJ
7~g0{W>Zm
if(totalRecords % everyPage == 0) 8XE0 p7
totalPage = totalRecords / everyPage; $a]dxRkz
else /FXfu
totalPage = totalRecords / everyPage + 1 ; &Vm[5XW
.5zJ bZ9
return totalPage; ;]e"bX
} V)@scB|>,
e1a %Rj~
privatestaticboolean hasPrePage(int currentPage){ U%olH >1K
return currentPage == 1 ? false : true; ?^0Z(<Arz
} j|w+=A1
27gm_*
privatestaticboolean hasNextPage(int currentPage, B) iJH
>.A:6
int totalPage){ cZ,_O~
return currentPage == totalPage || totalPage == z[Qv}pv
Z/;SR""wa
0 ? false : true; O`| ri5d
} s!\L1E
M>#S
z
L*38T\
} )HHzvGsL)
S]{Z_|h*j
:@L5=2Z+
[O'p&j@
]YKWa"
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。 y->iv%
h Nwb.[
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 U3QnWPt}>
O*7~t17
做法如下: ;RYKqUE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 C $;~=
EtG)2)
的信息,和一个结果集List: 1gr jK.x
java代码: DKH9O
w[_Uv4M
woKdI)f$
/*Created on 2005-6-13*/ :-8u*5QK]`
package com.adt.bo; mUw,q;{
Li^V?
import java.util.List; `VbG%y&I
c`Cn9bX
import org.flyware.util.page.Page; `z.#O\@o
]QQ"7_+
/** ^m9cEl^:nQ
* @author Joa XQPJ(.G
*/ 0]HIc
publicclass Result { Wov_jVdN\
+d96Z^KUhv
private Page page; cm<3'#~Q?
b"V-!.02
private List content; m 9S5;kB]
gS 3&,^
/** 8a{g EZT,
* The default constructor v]>(Ps )R
*/ 8'$n|<1X
public Result(){ y.2 SHn0
super(); ^S@b*
} |Can
<o
O_wS@:
/** &iivSc;#
* The constructor using fields MaM7u:kD#
* a6C~!{'nW
* @param page wim}}^H
* @param content .u&g2Y
*/ jC=_>\<|X*
public Result(Page page, List content){ P?
n`n!qZ
this.page = page; $ hapSrS
this.content = content; (H7q [UG|
} Vow+,,oh
HV?@MBM
/** h";sQ'us
* @return Returns the content. 5Z'pMkn3
*/ (nm&\b~j
publicList getContent(){ H^~!t{\
return content; ic+iTH
} bVym
;nbvn
/** 9,IGZ55C
* @return Returns the page. FqySnr JQ
*/ `B~%TEvMh
public Page getPage(){ e BPMT
return page; "A7tb39*
} E*zk?G|
+9t@eHJT1
/** fsu'W]f
* @param content ]v#Q\Q8>
* The content to set. uzOZxW[e
*/ tfO
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public void setContent(List content){ 9ZwhCsO
this.content = content; Ru/3>n
} [&$z[/4:8c
a[!':-R`s
/** YGB|6p(
* @param page %O-wMl
* The page to set. G7u7x?E:B`
*/ Y (Q8P{@(
publicvoid setPage(Page page){ YAD9'h]d\
this.page = page; ^(y4]yZ
} ufmFeeg
} lxbZM9A2
q;+qIV&.:
1-`8v[S
|dvcDx0|K
D*b>
l_
2. 编写业务逻辑接口,并实现它(UserManager, xJ4T7 )*
iVA_a8}
UserManagerImpl) k~R_Pq
S
java代码: JP#m}W
-<.>jX
x~
I cSt
/*Created on 2005-7-15*/ RSy1 wp4W
package com.adt.service; 1'h?qv^(
`eA 0Z:`g!
import net.sf.hibernate.HibernateException; ) E5ax~
Xa36O5$4]9
import org.flyware.util.page.Page; j&F&wRD%r
umc!KOkL
import com.adt.bo.Result; 4JucNGv
/%~`B[4F
/** FYzl- 7!Y
* @author Joa _:T\[sz5
*/ w1.~N`g$
publicinterface UserManager { |@ia(U~
NWFZ:h@v
public Result listUser(Page page)throws
I3A](`
>[[< 5$,T
HibernateException; fV3J:^)F
27)$;1MT:
} l-5-Tf&j
mIOx)`$
2e+DUZBoC
|
r2'B
O*CKyW_$t
java代码: qk+:p]2
cdk;HK_Ve.
qr:[y
/*Created on 2005-7-15*/ s:M:Ff
package com.adt.service.impl; VXC_Y
*<J**FhcMu
import java.util.List; ?k/Uw'J4u/
j5AW}
import net.sf.hibernate.HibernateException; Ltc>@
bBGLf)fsTG
import org.flyware.util.page.Page; WKP=[o^
import org.flyware.util.page.PageUtil; {jbOcx$t
qz?9:"~$C
import com.adt.bo.Result; k9a-\UIMet
import com.adt.dao.UserDAO; $H?v
import com.adt.exception.ObjectNotFoundException; TJ#<wIiX
import com.adt.service.UserManager; e<q;` H
%ePInpb
/** th !Gc
* @author Joa RE*;nSVFt
*/ bjbm"~
publicclass UserManagerImpl implements UserManager { w}+jfO9
5'6Oan7dL:
private UserDAO userDAO; 8g$pfHt|e
:0r@o:H
/** gmt`_Dpm$
* @param userDAO The userDAO to set. Tk)y*y
*/ .#CTL|x
publicvoid setUserDAO(UserDAO userDAO){ s %/3X\_
this.userDAO = userDAO; 5E4np`J
} IpHGit28
(tys7og$'
/* (non-Javadoc) tMC<\e
* @see com.adt.service.UserManager#listUser 5s8k^n"A
fAXF_wj
(org.flyware.util.page.Page) zK?[6n89f
*/ $5(co)C
public Result listUser(Page page)throws .a?GC(
%vgn>A?]1
HibernateException, ObjectNotFoundException { iWO16=
int totalRecords = userDAO.getUserCount(); aR+vY1d"
if(totalRecords == 0) rqSeh/<iD
throw new ObjectNotFoundException E<Efxb'p
PU[]
Nw
("userNotExist"); g\GuH?|
page = PageUtil.createPage(page, totalRecords); [/\}:#MLe
List users = userDAO.getUserByPage(page); bvi
Y.G3
returnnew Result(page, users); A(ql}cr
} ELPzqBI
5!-'~W
} :(E.sT"R
'8PZmS8X9
"cj6i{x,~w
Dy
mf
}mz@oEB#vF
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _I+QInD ;)
[Q6PFdQ_JT
询,接下来编写UserDAO的代码: VI/77
3. UserDAO 和 UserDAOImpl: $zKf>[K
java代码: RX \%R
Igrr"NuDZ
2XNO*zbve
/*Created on 2005-7-15*/ h:[%' htz
package com.adt.dao; /5pVzv+rm
wa2?%y_G
import java.util.List; !UDTNF?1
L3pNna
import org.flyware.util.page.Page; }I`"$2
/'O?
8X<
import net.sf.hibernate.HibernateException; nF`_3U8e
=~15q=XY0
/** '9.L5*wh]
* @author Joa `r+zNJ@q
*/ LR%]4$ /M
publicinterface UserDAO extends BaseDAO { 9=TjSRS
N"L@
publicList getUserByName(String name)throws lf-1;6nyk"
y<|8OTT
HibernateException; 9#cPEbb~
,%6!8vX
publicint getUserCount()throws HibernateException; {el[W,CT#
Tmjcc(
publicList getUserByPage(Page page)throws h6`v%7H?
]O]6O%.ao
HibernateException; .Yg7V'R1
WCRGqSr4
} 1 UdET#\
rrz^LD
@kBy|5
o+*7Q!
Pg4go10|
java代码: kT^|%bB[i
3e,"B
S)+
'3Ro`p{
/*Created on 2005-7-15*/ ;#)sV2F\&
package com.adt.dao.impl; +7E&IK
C)hS^D:
import java.util.List; 7!F<Uf,V3
l^!raoH]q
import org.flyware.util.page.Page; = Zi'L48
1#}}:
import net.sf.hibernate.HibernateException; &65I
6
import net.sf.hibernate.Query; ]?c9;U
1{15#W
import com.adt.dao.UserDAO; "d"6.ND
cb82k[L6
/** 46[k9T
* @author Joa JIL(\d
*/ q!f'?yFYK
public class UserDAOImpl extends BaseDAOHibernateImpl GBSuTu8
a1#",%{I
implements UserDAO { vLI'Z)\
]Ub"NLYV
/* (non-Javadoc) grVPu! B;
* @see com.adt.dao.UserDAO#getUserByName A9Kt^HR
:yxP3e%rp
(java.lang.String) b,hRk1
*/ xlIVLv6dO
publicList getUserByName(String name)throws dj-/%MU
T\v~"pMu*0
HibernateException { &a8%j+j
String querySentence = "FROM user in class zt!)7HBo
tXfXuHa
com.adt.po.User WHERE user.name=:name"; JIatRc?g
Query query = getSession().createQuery !(A<
gkhmQd
(querySentence); Fe L !%z
query.setParameter("name", name); ?uh%WN6nU]
return query.list(); =[do([A
} aE(DNeG-H
%_(X n
/* (non-Javadoc) ;.+C
* @see com.adt.dao.UserDAO#getUserCount() ,Jrm85oG
*/ {iXQUj
publicint getUserCount()throws HibernateException { )6b`1o!7
int count = 0; 0g'MFS
String querySentence = "SELECT count(*) FROM 6qR5A+|;
GahIR9_2
user in class com.adt.po.User"; >1BDt:G36
Query query = getSession().createQuery bt=z6*C>A
yRy^'E~
(querySentence); Uc<BLu;
count = ((Integer)query.iterate().next \ORE;pG
^^z_[Ih
()).intValue(); `|p8zV
return count; ;q?WU>c{?
} F]GX;<`
Ve\.7s
/* (non-Javadoc) sq_
yu(
* @see com.adt.dao.UserDAO#getUserByPage eNDc220b
dnzZ\t>U
(org.flyware.util.page.Page) TUN6`/"
*/ O[+\` 63F=
publicList getUserByPage(Page page)throws R+# g_"1@p
+!/pzoWpE
HibernateException { BD2Gv)?g
String querySentence = "FROM user in class JD)wxoeg
@Zzg^1Ilpu
com.adt.po.User"; "Wg5eML0
Query query = getSession().createQuery o*5b]XWw
7Vo[zo
(querySentence); Il]p >B
query.setFirstResult(page.getBeginIndex()) (j&7`9<5
.setMaxResults(page.getEveryPage()); mXT{c=N)w
return query.list(); J3 xi5S
} ra
F+Bt`
3ih:t'N-
} 8;i'dF:)
Dc9Fb^]QOG
W~& QcSWqD
R-6km Tex>
QE6L_\l
至此,一个完整的分页程序完成。前台的只需要调用 J9);(
awgS5We|
userManager.listUser(page)即可得到一个Page对象和结果集对象 _iH:>2p 5R
lm8<0*;,
的综合体,而传入的参数page对象则可以由前台传入,如果用 ({<qs}H"
, }B{)
webwork,甚至可以直接在配置文件中指定。 YeI|&FMX
.2
}5Dc,eR
下面给出一个webwork调用示例: ?
@- t.N
java代码: ]Wn=Oc{F
2,r jy|R`
xJ^pqb
/*Created on 2005-6-17*/ %'MR;hQsd8
package com.adt.action.user; .*Axr\x3
wKE}BO >
import java.util.List; W]5sqtF;6
[Qn=y/._r
import org.apache.commons.logging.Log; r)gtx!bx
import org.apache.commons.logging.LogFactory; uA%cie
import org.flyware.util.page.Page; 08z?i
`08}y*E
import com.adt.bo.Result; _]M:
import com.adt.service.UserService; 2NF#mWZ(s
import com.opensymphony.xwork.Action; es1'z.U J
-+n?Q;
/** 7#sb},J{
* @author Joa ^ux"<?
*/ OSkBBo]~z
publicclass ListUser implementsAction{ gmCB4MO
V4. }wz_Y
privatestaticfinal Log logger = LogFactory.getLog \eCQL(_
Wdp4'rB
(ListUser.class); ]4[^S.T=
#{~3bgY
private UserService userService; gcF V$
.~%,eF;l$
private Page page; *40Z}1ng
15cgmZsS
privateList users; xHaoSs*C9
i> PKE.
/* }-PV%MNud
* (non-Javadoc) $ItPUYi";
* oN[#C>#(
* @see com.opensymphony.xwork.Action#execute() y*j8OA.S
*/ ?>iZ){0,
publicString execute()throwsException{ R]y9>5 'U
Result result = userService.listUser(page); 89fl\18%
page = result.getPage(); S%7%@Qs"%
users = result.getContent(); 1-}$sO c
return SUCCESS; r' J3\7N!u
} +\66; 7]s
An=Q`Uxt/
/** /i
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* @return Returns the page. *Edr\P
*/ 9S{?@*V
public Page getPage(){ z1LY|8$G
return page; 7J$Yd976
} '?b.t2
6gD|QC~;
/** C/!8NV1:4
* @return Returns the users. 1#jvr_ ga
*/ _R;+}1G/
publicList getUsers(){ ^jg{MTa
return users; dMoN19F
} *Bx'g|
u
o88Dz}a
/** f/e2td*A
* @param page >}B~~C;
* The page to set. /[Sy;wn
*/ UdX aC= Q
publicvoid setPage(Page page){ OuU ]A[r
this.page = page; ?r}!d2:dX
} FUKE.Uxd
u^uo=/
/** 9Jp"E5Ql)
* @param users Tp%4{U/0`
* The users to set. .E0*lem'hE
*/ ^g*/p[
publicvoid setUsers(List users){ ii]'XBSVd
this.users = users; -I{J]L$S#
} U4,hEnJBT
nuX W/7M
/** n`g:dz
* @param userService RYKV?f#[H
* The userService to set. eO=!(
*/ P%xz"l i
publicvoid setUserService(UserService userService){ `-)Fx<e
this.userService = userService; be5NasC
} # fl%~Y
} pd
X"M>
&<%U7?{~
w\3'wD!
7`6JK
ti9cfv>
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, !YEU<9
&-6D'@
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 k0R;1lZ0n
1">]w2je:
么只需要: m1lfC
java代码: YP vg(T
Y&_1U/}h
9=Rj9%
<?xml version="1.0"?> h\^> s$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork JPT VZ
AAt<{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ld*RL:G
Rd.[8#7VE
1.0.dtd"> G0eJ<*|_ 3
JTg0T+
<xwork> 1eDc:!^SD
Q{Lsr,
<package name="user" extends="webwork- ps6c>AN`A&
"Z6: d"S`
interceptors"> t#h<'?\E
$MG. I[h
<!-- The default interceptor stack name `;R|SyrX
-/#tQ~{gs
--> <ArP_!
`3
<default-interceptor-ref kV Z5>D$
ywV8s|o
name="myDefaultWebStack"/> c/57_fOK
20f):A6
<action name="listUser" R4|<Vp<U2
l7r!fAV-f
class="com.adt.action.user.ListUser"> __V6TDehJ$
<param ;zO(bj>
>AW=N
name="page.everyPage">10</param> '2%/h4jY
<result =}~hbPJM
kM?p >V6
name="success">/user/user_list.jsp</result> y]`@%V2P
</action> &xqr&(o
Xsc5@O!
</package> HSOdqjR*
:=tPC A=
</xwork> a4}2^K
p=(;WnsK
uOrvmb
W+~ w
.SdEhW15)
1W5\
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 "ppT<8Qi'
VPTT*a`
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。 )Cz^Xp)#
>cD+&h34
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 c])b?dJ*
_ QM
Al`[Iu&
Ga%]$4u
"/?*F\5
我写的一个用于分页的类,用了泛型了,hoho Mf&W<n^j
<8At= U
java代码: v; ;X2 a1k
puv*p%E
6Bp{FOj:Ss
package com.intokr.util; v|Tg %
UG>OL2m>5
import java.util.List; |Tz4 xTK
^[CD- #
/** !DCJ2h%E[_
* 用于分页的类<br> m=S[Y^tR
* 可以用于传递查询的结果也可以用于传送查询的参数<br> |pp @
* HJ5m5':a
* @version 0.01 lq_W;L
* @author cheng ~]/X,Cf
*/ 38Z"9
public class Paginator<E> { Rhx7eU#&
privateint count = 0; // 总记录数 BQBO]<99
privateint p = 1; // 页编号 h ;5
-X7
privateint num = 20; // 每页的记录数 +c\s%Gzrh
privateList<E> results = null; // 结果 vd /_`l.D
KX)xCR~
/** r[Q$w>
* 结果总数 3_T'TzQu
*/ RQU5T 2,
publicint getCount(){ Z=!*7@QY
return count; !r.}y|t?;
} [NvEXTd
B:z -?u#B
publicvoid setCount(int count){ =,[46 ;q
this.count = count; Xt=&
} i&>,aiH@
gH\r# wy|
/** 0 \LkJ*i
* 本结果所在的页码,从1开始 =pcj{B{qa
* >Fld7;L?<
* @return Returns the pageNo. Mn~A;=%qF
*/ ''BP4=r5n
publicint getP(){ >W'SG3Hmc
return p; <\^X,,WtO
} :/%Vpdd@
YC=BP5^
/** h;4g#|,
* if(p<=0) p=1 |7`Vw Z
*
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* @param p M:`hb$k:
*/ Sc6wC H
publicvoid setP(int p){ X=\#n-*
if(p <= 0) C3@.75-E
p = 1; F` I-G~e
this.p = p; r$v?[x>+K
} [k'Ph33c
;wQWt_OtuJ
/** % C
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* 每页记录数量 :GK{JP
*/ j5'Jp}
publicint getNum(){ 6>=>Yj
return num; )1fQhdO}x
} Xp} vJl
~#a1]w
/** @IiT8B
* if(num<1) num=1 HnP;1Gi
*/ RaU.yCYyu
publicvoid setNum(int num){ dWqFP
if(num < 1) 4(aesZ8h
num = 1; 7-o=E=
this.num = num; iQ9#gPk_9
} U[A*A^$c}
Ab2g),;c
/** CY>NU
* 获得总页数 rIb[gm)Rk
*/ 5&X
publicint getPageNum(){ Ve8!
return(count - 1) / num + 1; ==XP}w)m
} z t,-O7I'1
n~&R_"mv(
/** k9Sqp:l,
* 获得本页的开始编号,为 (p-1)*num+1 q6Q=Zo@
*/ }qD.Ek
publicint getStart(){ _yWH\5@
return(p - 1) * num + 1; Y$ChMf
} W;N/Y3Lb
Q?a"uei[
/** 3,vH:L4
* @return Returns the results. :):Y6)giBD
*/ /XSPVc<
publicList<E> getResults(){ phc1AN=[E
return results; f0D Ch]
} $k`8Zx w
@^` <iTK&p
public void setResults(List<E> results){ 4*+EUJ|
this.results = results; 7@lXN8_f
} j&Hn`G
*(vq-IE\$
public String toString(){ -YuvEm#f
StringBuilder buff = new StringBuilder h+74W0
$
zDl, bLiJ
(); O h"^
buff.append("{"); i9xv`Ev=R
buff.append("count:").append(count); W1@;94Sb~
buff.append(",p:").append(p); X#3<hN*v
buff.append(",nump:").append(num); `U g.c
buff.append(",results:").append oX}n"5o:
,oG"wgf
(results); w//w$}v
buff.append("}"); Y=rr6/k
return buff.toString(); b}4/4Z.
} N/%#GfXx
c}QJ-I
} aqM_t
!n{c#HfG
UeICn@)\y