Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 28qlp>U
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 {gh<SZsE
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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 Zc'^iDAY
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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 uS5G(} [
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分页支持类: U"=Lzo.0
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java代码: nyetK
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package com.javaeye.common.util; ,0c]/Sd*p
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import java.util.List; q@g#DP+C
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publicclass PaginationSupport { (&Rql7](8
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publicfinalstaticint PAGESIZE = 30; j
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privateint pageSize = PAGESIZE; JIIc4fyy8s
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privateList items; %o5'M^U
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privateint totalCount; XFYa+]B2q
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privateint[] indexes = newint[0]; bp<,Xfl
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privateint startIndex = 0; 5|cRHM#
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public PaginationSupport(List items, int Zrp-Hv27,,
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totalCount){ N<ux4tz
setPageSize(PAGESIZE); ,}O33BwJp
setTotalCount(totalCount); #m17cDL
setItems(items); {Kf5a
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setStartIndex(0); A{e>7Z72
} qV;I<AM
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public PaginationSupport(List items, int /EG'I{oC
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totalCount, int startIndex){ bYoBJ
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setPageSize(PAGESIZE); s/B_
setTotalCount(totalCount); :d pwr9)
setItems(items); RL$%Vy0
setStartIndex(startIndex); &Q#*Nnb3
} li,rPUCt
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public PaginationSupport(List items, int k>\v]&|T`
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totalCount, int pageSize, int startIndex){ >JAWcT)d
setPageSize(pageSize); [:(/cKo
setTotalCount(totalCount); ALV(fv$cD
setItems(items); ,i1BoG
setStartIndex(startIndex); bLSc=f&
} ^/6P~iK'
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publicList getItems(){ P@f#DX
)
return items; k'k}/Hxub
} C
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publicvoid setItems(List items){ ([
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this.items = items; U1HG{u,"y
} D6H?*4f]
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publicint getPageSize(){ h!v<J
return pageSize; $wi4cHh
} -cijLlz%+
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publicvoid setPageSize(int pageSize){ m[KmXPFht1
this.pageSize = pageSize; JXMH7
} lx=tOfj8
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publicint getTotalCount(){ *c [^/
return totalCount; T=)qD2?
} !\[JWN@v
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publicvoid setTotalCount(int totalCount){ d#]hqy
if(totalCount > 0){ :vX%0|
this.totalCount = totalCount; Fi67 "*gE
int count = totalCount / ZX64kk+
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pageSize; jw9v&/-
if(totalCount % pageSize > 0) _Z!@#y@j
count++; 8#VD u(
indexes = newint[count]; i#hFpZ6u
for(int i = 0; i < count; i++){ ~!!\#IX
indexes = pageSize * dJ
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i; b,YNCb]H
} 0#Lmajs
}else{ aZCq{7Xs
this.totalCount = 0; W7
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} XL^05
} vXRY/Zzj1
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publicint[] getIndexes(){ M:{Aq&.
return indexes; S,nELV~!
} )-emSV0zE
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publicvoid setIndexes(int[] indexes){ as!a!1
this.indexes = indexes; (y 7X1Qc)
} F -,chp
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publicint getStartIndex(){ "I)zi]vk
return startIndex; ,!b<SQ5M
} |5tZ*$nGa
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publicvoid setStartIndex(int startIndex){ ?q9]H5\
if(totalCount <= 0) [#q]B=JB
this.startIndex = 0; BhzD V
elseif(startIndex >= totalCount) <y] 67:"<v
this.startIndex = indexes QcW8A ,\q
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[indexes.length - 1]; flo$[]`.7
elseif(startIndex < 0) d_M+W@{
this.startIndex = 0; Y55u-9|N
else{ UJSIbb5
this.startIndex = indexes 8ZVQM7O
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[startIndex / pageSize]; .WqqP
} Lr D@QBT
} j}eb
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publicint getNextIndex(){ L;%w{,Ji
int nextIndex = getStartIndex() + @)uV Fw"\
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pageSize; V7Cnu:0_
if(nextIndex >= totalCount) f4b9o[,s2e
return getStartIndex(); %g}d}5s
else <cp9+P <
return nextIndex; 'v~'NWfd
} PnA{@n\
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publicint getPreviousIndex(){ `.@sux!lu
int previousIndex = getStartIndex() - 0DmA3
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pageSize; z6C(?R
if(previousIndex < 0) AtG~!)hG
return0; _(F-(X|
else )6C+0b*
return previousIndex; {h7 vJ^
} 3W%6n-*u
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} *uhQP47B
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抽象业务类 r
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java代码: 3-
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/** OL>>/T
* Created on 2005-7-12 bTc>-e,
*/ FnA Kfh(
package com.javaeye.common.business; D4!;*2t
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import java.io.Serializable; C~qZ&
import java.util.List;
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import org.hibernate.Criteria; y9 {7+]
import org.hibernate.HibernateException; %Hbq3U30
import org.hibernate.Session; 112WryS
import org.hibernate.criterion.DetachedCriteria; qjP~F
import org.hibernate.criterion.Projections; n[iwi
import ^?`fN'!p
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org.springframework.orm.hibernate3.HibernateCallback; \5r^D|Rp}
import 9:USxFM
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org.springframework.orm.hibernate3.support.HibernateDaoS 6(bN*.
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upport; K$,Zg
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import com.javaeye.common.util.PaginationSupport; Xfq`k/ W
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public abstract class AbstractManager extends '^m.vS!/
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HibernateDaoSupport { .n]"vpWm[
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privateboolean cacheQueries = false; ,=u;1
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privateString queryCacheRegion; Jw;~ $
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publicvoid setCacheQueries(boolean ]<>cjk.ya
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cacheQueries){ O2{["c
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this.cacheQueries = cacheQueries; SH?McBxS
} #Q8_:dPY
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publicvoid setQueryCacheRegion(String %R c#/y
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queryCacheRegion){ 1&=)Bxg4
this.queryCacheRegion = @Z~YFnEJi
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queryCacheRegion; =OHX5:Z
} 5~[7|Y
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publicvoid save(finalObject entity){ 9Y:I)^ek
getHibernateTemplate().save(entity); 3x+lf4"
} 0Qt!w(
E )_n?>Ar
publicvoid persist(finalObject entity){ bw P=f.
getHibernateTemplate().save(entity); ,>a!CnK=
} j&d5tgLB
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publicvoid update(finalObject entity){ 1Toiqb/
getHibernateTemplate().update(entity); P8z%*/
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} MbRTOH
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publicvoid delete(finalObject entity){ u9hd%}9Qd?
getHibernateTemplate().delete(entity); yJ $6vmQ
} _re# b?
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publicObject load(finalClass entity, ( eTrqI`
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finalSerializable id){ Dp([r
return getHibernateTemplate().load %F 2h C
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(entity, id); h3?>jE=H
} SOOVUMj
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publicObject get(finalClass entity, WO qDW~
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finalSerializable id){ g<j)
return getHibernateTemplate().get Z =+Z96
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(entity, id); JsJP%'^/R
} <w2h@ea
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publicList findAll(finalClass entity){ =tOB fRM
return getHibernateTemplate().find("from FiUQ2w4
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" + entity.getName()); ` 2W^Ui,4
} M =^d
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publicList findByNamedQuery(finalString S<0 &V
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namedQuery){
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return getHibernateTemplate V]zc-gYI
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().findByNamedQuery(namedQuery); 7}kJp%-
} ! ?g+'OM
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publicList findByNamedQuery(finalString query, *fg2bz<~[B
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finalObject parameter){ ZNQx;51
return getHibernateTemplate 5CY%h
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().findByNamedQuery(query, parameter); W@d&X+7e
} QLd*f[n
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publicList findByNamedQuery(finalString query, ^&>B,;Wu
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finalObject[] parameters){ ;U* /\+*h
return getHibernateTemplate /v
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().findByNamedQuery(query, parameters); sINQ?4_8T
} j"qND=15
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publicList find(finalString query){ ?
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return getHibernateTemplate().find h4;kjr}h}
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(query); G2`z?);1b
} ,2FK$:M\
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publicList find(finalString query, finalObject o "VKAP
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parameter){ "_WN[jm
return getHibernateTemplate().find #3&@FzD_P
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(query, parameter); Geq]wv8
} l2
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: K|
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public PaginationSupport findPageByCriteria 'PF>#X''
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(final DetachedCriteria detachedCriteria){ eEZgG=s
return findPageByCriteria oIhKMQ;jh
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?NMk|+
} 8b/$Qp4d
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public PaginationSupport findPageByCriteria [IYVrT&C'
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(final DetachedCriteria detachedCriteria, finalint 0 +=sBk (
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startIndex){ $k~TVm
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return findPageByCriteria zgb$@JC
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(detachedCriteria, PaginationSupport.PAGESIZE, %Ig$: I(o
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startIndex); Y1PR?c
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} bzi"7%c
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public PaginationSupport findPageByCriteria <[dcIw<7
& zDuh[j}
(final DetachedCriteria detachedCriteria, finalint U6.aoqb%
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pageSize, z!}E2j_9P
finalint startIndex){ 6
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return(PaginationSupport) 2 @#yQB1
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getHibernateTemplate().execute(new HibernateCallback(){ 5JzvT JMx
publicObject doInHibernate n>'(d*[e&
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(Session session)throws HibernateException { ^j}C]cq{Xg
Criteria criteria = F-m%d@P&X
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detachedCriteria.getExecutableCriteria(session); F6\{gQ<E
int totalCount = d( v"{N}
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((Integer) criteria.setProjection(Projections.rowCount # h;
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()).uniqueResult()).intValue(); {)" 3
criteria.setProjection (|QJ[@?q
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(null); 0Ui.nz j
List items = i2<z"v63
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criteria.setFirstResult(startIndex).setMaxResults #T7v]@K67
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(pageSize).list(); lod+]*MD
PaginationSupport ps = m.<_WXH
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new PaginationSupport(items, totalCount, pageSize, %-n)L
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startIndex); Ks.b).fH
return ps; ](r}`u%}y
} Hx#YN*\.M
}, true); qTuR[(
} Mq>
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public List findAllByCriteria(final ^to*ET{0
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DetachedCriteria detachedCriteria){ aT0~C.vT
return(List) getHibernateTemplate 2C
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().execute(new HibernateCallback(){ lSX1|,B7:]
publicObject doInHibernate \+o\wTW
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(Session session)throws HibernateException { iYXD }l;r
Criteria criteria = RC_Pj)
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detachedCriteria.getExecutableCriteria(session); "c%wq0
return criteria.list(); lNe4e6
} wv\X
}, true); E1QJ^]MG.
} 4=,J@N-
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public int getCountByCriteria(final //@6w;P
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DetachedCriteria detachedCriteria){ }c,b]!:
Integer count = (Integer) TEV DES
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getHibernateTemplate().execute(new HibernateCallback(){ lelmX
publicObject doInHibernate uaIAVBRcS
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(Session session)throws HibernateException { =3(v4E':5
Criteria criteria = .tRm1&Qi
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detachedCriteria.getExecutableCriteria(session); @gP*z6Z
return alJ0gc2?
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criteria.setProjection(Projections.rowCount ?_ H9>/:.
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()).uniqueResult(); /d&m#%9Up]
} x1:mT[[$
}, true); BK!Yl\I<
return count.intValue(); &4%pPL\f
} dS1HA>c)O
} *R6lK&
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用户在web层构造查询条件detachedCriteria,和可选的 ? 2}%Rb39
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )G48,.
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PaginationSupport的实例ps。 CPZ{
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ps.getItems()得到已分页好的结果集 ~(GvjB/C8
ps.getIndexes()得到分页索引的数组 *~8F.cx
ps.getTotalCount()得到总结果数 O?vh]o
ps.getStartIndex()当前分页索引 Z}O]pm>=G
ps.getNextIndex()下一页索引 qGX@mo({
ps.getPreviousIndex()上一页索引 h3F559bw/<
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 x(c+~4:_M
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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 &YIL As^8A
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一下代码重构了。 O/eZ1YAC
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我把原本我的做法也提供出来供大家讨论吧: z$&B7?
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首先,为了实现分页查询,我封装了一个Page类: s8
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java代码: Y%i<~"k
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/*Created on 2005-4-14*/ K+Him]
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package org.flyware.util.page; Dbn~~P
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/** 1(;{w+nM
* @author Joa r(^00hvH
* |?KYY0
*/ {/noYB<;
publicclass Page { K qJE?caw
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/** imply if the page has previous page */ =R0f{&"i
privateboolean hasPrePage; -#I]/7^
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/** imply if the page has next page */ Pz50etJ
privateboolean hasNextPage; r 2:{r`ocM
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/** the number of every page */ feXo"J
privateint everyPage; -O &>HA
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/** the total page number */ X&[Zk5DU*
privateint totalPage; KaEaJ
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/** the number of current page */ 0=,Nz
privateint currentPage; X!h>13fW
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/** the begin index of the records by the current {
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query */ ^.J_ w
privateint beginIndex; SB%D%Zx6'%
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/** The default constructor */ pwMA,X/{
public Page(){ ln_&Ux+l
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} /@
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/** construct the page by everyPage 1*A^v
* @param everyPage @Yt394gA%\
* */ I{w(`[Nxw*
public Page(int everyPage){ bR3Crz(9G
this.everyPage = everyPage; i).Vu}W#S
} x((u
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/** The whole constructor */ l|+$4 Nb2
public Page(boolean hasPrePage, boolean hasNextPage, F7'MoH
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f5//?ek
int everyPage, int totalPage, a)lCp
int currentPage, int beginIndex){ 6}Y==GPt
this.hasPrePage = hasPrePage; [!U%''
this.hasNextPage = hasNextPage; H%vgPQ8
this.everyPage = everyPage; 6,4vs+(|\
this.totalPage = totalPage; Wpf~Ji6||
this.currentPage = currentPage; nHF66,7t
this.beginIndex = beginIndex; ,|O6<u9
} T}J)n5U}\
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/** ~_i=hx
* @return |./:A5_h
* Returns the beginIndex. PM!JjMeQh
*/ (J4( Ge
publicint getBeginIndex(){ Dlz0*eHD
return beginIndex; nYyKz
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} H6Zo|n
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/** xVsI#`<a
* @param beginIndex h% >ZN-K)
* The beginIndex to set. #Ey_.4S
*/ LawE3CD
publicvoid setBeginIndex(int beginIndex){ K!AA4!eUzM
this.beginIndex = beginIndex; h}|.#!C3
} i~E0p
,
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/** DN%JT[7
* @return aAqM)T83
* Returns the currentPage. }#tbK 2[
*/ gs+nJ+b
publicint getCurrentPage(){ H|e7IsY%
return currentPage; {|$kI`h,3-
} cRs\()W
3 }sy{Mx%9
/** fP
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* @param currentPage ]Ky`AG`2~
* The currentPage to set. N MkOx$
*/ VN09g&
publicvoid setCurrentPage(int currentPage){ }@.@k6`n
this.currentPage = currentPage; (mbm',%- (
} Dy5&-yk
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/** Mi
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* @return ouyZh0G
* Returns the everyPage. 'h;qI&
*/ w^cQL%
publicint getEveryPage(){ Mk9J~'C_
return everyPage; L{1[:a)']B
} $ r-rIW5\
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/** 'w1ll9O
* @param everyPage Zqf
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* The everyPage to set. F <iV;+
*/ 9s!R_R&W.
publicvoid setEveryPage(int everyPage){ ;dfIzi
this.everyPage = everyPage; Ve9)?=!
} %<8?$-[
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/** OW6dK#CFt
* @return ~233{vh$=>
* Returns the hasNextPage. Bx)!I]gi_
*/ )l(DtU!E
publicboolean getHasNextPage(){ %p7onwKq0
return hasNextPage; Ik,N/[
} 9W-"mD;
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/** ve"tbNL
* @param hasNextPage mQt0?c _
* The hasNextPage to set. PB*G#2W
*/ PYNY1|3
publicvoid setHasNextPage(boolean hasNextPage){ vo:h"ti
this.hasNextPage = hasNextPage; *6][[)(
} <Vt"%C
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/** 4Q1R:Ra
* @return ,ExY.'%1
* Returns the hasPrePage.
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*/ Jq"3xj
publicboolean getHasPrePage(){ vV=rBO0a?
return hasPrePage; [5!{>L`
} pKLNBR|
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/** =b"{*Heuw
* @param hasPrePage J0f!+]~G3
* The hasPrePage to set. =eS?`|
*/ 0dsL%G~/N
publicvoid setHasPrePage(boolean hasPrePage){ Kv:.bHN}
this.hasPrePage = hasPrePage; pI.8Ip_r
} u^i3 @JuX
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/** 4\ElMb[]
* @return Returns the totalPage. .=yv m
* X>pCkGE
*/ BhjDyB
publicint getTotalPage(){ BaUuDo/ZO
return totalPage; Q t>|TGz
} uK#2vgT
u] G
/** `SZ-o{
* @param totalPage r?
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* The totalPage to set. !?J-Y
*/ 5-H"{29
publicvoid setTotalPage(int totalPage){ PQ;9iv
this.totalPage = totalPage; B>I:KGkV
} _d^d1Q}V
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} +Y;hVcE9
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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 Y]`o-dV
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个PageUtil,负责对Page对象进行构造: Lr
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java代码: II=!E
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/*Created on 2005-4-14*/ sk:B;.z
package org.flyware.util.page; v>mK~0.$
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import org.apache.commons.logging.Log; t.\Pn4
import org.apache.commons.logging.LogFactory; eR`Q7]j] -
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/** amX1idHo^
* @author Joa 1D!MXYgm1b
* WjSu4
*/ ?'H+u[1.
publicclass PageUtil { cf^ i!X0
mQSn*;9\T3
privatestaticfinal Log logger = LogFactory.getLog )%kiM<})
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(PageUtil.class); M} ri>o
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/** Wi,)a{
* Use the origin page to create a new page Akws I@@
* @param page k!bJ&} Q(b
* @param totalRecords 35x]'
* @return n0EW
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*/ DSq?|H
publicstatic Page createPage(Page page, int @,2,(=l*C
*5hbD-a:
totalRecords){ J p^#G2
return createPage(page.getEveryPage(), @SaxM4
4b,+;
page.getCurrentPage(), totalRecords); &m\Uc
} oSjYp(h:
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/** 4pelIoj
* the basic page utils not including exception ^K4?uABc
>vYb'%02
handler XIdC1%pr;
* @param everyPage IDpx_
* @param currentPage Bga4kjfmk
* @param totalRecords .wlKl[lE2
* @return page f87XE";:A
*/ s%>8y\MaK
publicstatic Page createPage(int everyPage, int GDiyFTr
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currentPage, int totalRecords){ 4M6[5RAW{
everyPage = getEveryPage(everyPage); w-NTw2x,&
currentPage = getCurrentPage(currentPage); >pJ#b=
int beginIndex = getBeginIndex(everyPage, ;kR=vv
3J/l>1[
currentPage); )iK:BL*Nw
int totalPage = getTotalPage(everyPage, cW"DDm
g
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totalRecords); |b^UPrz)VS
boolean hasNextPage = hasNextPage(currentPage, $A/?evJi8R
}s6Veosl
totalPage); |YV> #l
boolean hasPrePage = hasPrePage(currentPage); e"{"g[b/7
{^:NII]
returnnew Page(hasPrePage, hasNextPage, EQw7(r|v:
everyPage, totalPage, Di}M\!-[
currentPage, F?cwIE\J
/;[x3}[
beginIndex); c^puz2
} &"27U
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privatestaticint getEveryPage(int everyPage){ D:z_FNN
return everyPage == 0 ? 10 : everyPage; R?tjobk!
} ?Pf#~U_
c9c3o{(6Y
privatestaticint getCurrentPage(int currentPage){ )~ &gBX
return currentPage == 0 ? 1 : currentPage; ab.B?bx
} \j BA4?(S
0@y`iZ]
1S
privatestaticint getBeginIndex(int everyPage, int Q00v(6V46
:("@U,
currentPage){ sX*L[3!vN
return(currentPage - 1) * everyPage; EwuRIe;D
} /& c2y=/'C
$<&_9T#&w
privatestaticint getTotalPage(int everyPage, int BSJS4+,E
^SsnCn-e
totalRecords){ x
ju*zmu
int totalPage = 0; gX(Xj@=(&
0M&~;`W}
if(totalRecords % everyPage == 0) 19pFNg'kA
totalPage = totalRecords / everyPage;
s_+.xIZ
else F;kKn:X L
totalPage = totalRecords / everyPage + 1 ; )`ixT)
C@zG(?X
return totalPage; N^PkSf[)h5
} @$;8k }
s16, *;Z
privatestaticboolean hasPrePage(int currentPage){ H8HVmfM
return currentPage == 1 ? false : true; ?UOaqcL
} {cO8q
}L
' u;Zw%O(J
privatestaticboolean hasNextPage(int currentPage, v<<ATs%w
_g( aO70Zu
int totalPage){ wi+L4v
return currentPage == totalPage || totalPage == Yo=$@~vN]
:2/jI:L~
0 ? false : true; .}Ys+d1b9c
} E`hR(UL
?
euRKYGW
GRVF/hPn
} BSB&zp
qbCU&G|)
f1elzANy
:PY6J}:
1CSGG'J]E
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。 ]\oT({$6B
1;i|GXY:h
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 4GG>n
#n15_cd
做法如下: q8;MPXSG3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 4`fV_H.8
k'PvQl"I
的信息,和一个结果集List: a^E>LJL
java代码: Sl'$w4s
~-uf%=
^6F, lS _t
/*Created on 2005-6-13*/ z 0zB&}
package com.adt.bo; )PYh./_2
%|^,Q -i,
import java.util.List; ?9!9lSH6%
;*9<lUvu
import org.flyware.util.page.Page; 1LhZmv
h(J$-SUs
/** C&%NO;Ole
* @author Joa gyV`]uqG
*/ 7N@[Rtv
publicclass Result { &,:!gYN
zxD=q5in
private Page page; [Ob'E!;<
V"2 G
private List content; +RR6gAma}<
:RJo#ape
/** j6$@vA)
* The default constructor BA@M>j6d
*/ *:"60fkoU
public Result(){ e8oAGh"
super(); f&$;iE
} f#m@eb
4,h)<(d{
/** @,;h!vB*=
* The constructor using fields m|x_++3
* :hW(2=%
* @param page tX@y ]"
* @param content _T~&kwe
*/ VAUd^6Xdwx
public Result(Page page, List content){ I>vU;xV\m
this.page = page; ggkz
fg &
this.content = content; u^c/1H:6
} 2_o\Wor#
9) $[W
/** U:eX^LE7
* @return Returns the content. <SOG?Lh~
*/ ,{msJyacmR
publicList getContent(){ B]}gfVO
return content; a}|<*!4zUQ
} 9IrCu?n9b
iC^G^ ~V+H
/** YGs'[On8
* @return Returns the page. %6^nb'l'C
*/ Qb%;
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public Page getPage(){ hNkv lk'Ui
return page; S?a4IK
} iC^91!<
w`+-xT%
/** v*.iNA;&i
* @param content bj 8pqw|;
* The content to set. z7L+wNYwg
*/ !wfUD2K1
public void setContent(List content){ .f;@OqU
this.content = content; u*uHdV5
} dn?'06TD
a.JjbFL
/** ?$tD
* @param page L]"$dF
* The page to set. b\o>4T
*/
< .e4
publicvoid setPage(Page page){ f#!nj]}#
this.page = page; 1q5S"=+W[
} Q8QB{*4
} vdB2T2F
i^Jw`eAmT
;#IrHR*Bk
K7(k_4
>hq{:m
2. 编写业务逻辑接口,并实现它(UserManager, O'#;Ge/,
j%Z5[{!/,X
UserManagerImpl) C2=PGq
java代码: iQG]v[$
GBR$k P
*<SXzJ(
/*Created on 2005-7-15*/ yM9>)SE5`
package com.adt.service; ~UQ<8`@a
5!$sQ@#}D
import net.sf.hibernate.HibernateException; +opym!\
hJSWh5]
import org.flyware.util.page.Page; YDYNAOThnb
)D'#>!Y
import com.adt.bo.Result; be]/ROP>H
3&{6+ A
/** 'W54 T
* @author Joa F`(;@LO
*/ "cly99t
publicinterface UserManager { ZF#n(Y?
'Z9UqEGV
public Result listUser(Page page)throws a MFUj+^
tQUKw@@Q
HibernateException; upZc~k!1\
#*"V'dj;e
} 5=p<"*zJ
4oryTckS
V6((5o#
b2[U3)|oO
OkISRj'!U
java代码: IuAu_`,Ndi
\pTC[Ry1
O:T
49:R}r
/*Created on 2005-7-15*/ |*h{GX.(
package com.adt.service.impl; |]?W`KN0
8f)pf$v`
import java.util.List; -wl&~}%M
dV'^K%#
import net.sf.hibernate.HibernateException; eX}aa0
'/0e!x/8
import org.flyware.util.page.Page; \Zx&J.D
import org.flyware.util.page.PageUtil; L2}<2
7 H:y=?X6
import com.adt.bo.Result; F]>+pU
import com.adt.dao.UserDAO; v.TgB)
import com.adt.exception.ObjectNotFoundException; -JPkC(V7]
import com.adt.service.UserManager; 8@S]P0lk
4tUt"N
/** n4 N6]W\5
* @author Joa ed_+bCNy
*/ l7VTuVGUJ
publicclass UserManagerImpl implements UserManager { q{b-2k
Lr6C@pI
private UserDAO userDAO; c{?SFwgd
2$!,$J-<Y
/** es%py~m)
* @param userDAO The userDAO to set. S<'_{u z
*/ Q2woCxB
publicvoid setUserDAO(UserDAO userDAO){ Lpkx$QZ
this.userDAO = userDAO; #;@I.
} a$^)~2U{
Pw7uxN`
/* (non-Javadoc) P,WQN[(+
* @see com.adt.service.UserManager#listUser }opMf6`w
1|H4]!7kE
(org.flyware.util.page.Page) :(yut
*/ d^!3&y&
public Result listUser(Page page)throws RIO?rt;
Y= =5\;-
HibernateException, ObjectNotFoundException { l.Ev]G/5
int totalRecords = userDAO.getUserCount(); .j|uf[?h
if(totalRecords == 0) /Qef[$!(
throw new ObjectNotFoundException .Z"`:4O
9(z) ^G
("userNotExist"); [E6ceX0
page = PageUtil.createPage(page, totalRecords); e00}YWf%
List users = userDAO.getUserByPage(page); _G.!^+)kEm
returnnew Result(page, users); Ef?|0Gm
} lVd-{m)
;
2V$`k
} !hS)W7!ik
OU#p^5K
94t`&jZ&|u
6d/v%-3
+s;Vfc$b]H
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 hmG8
{h/
kz6fU\U
询,接下来编写UserDAO的代码: 5ZH3}B^L$
3. UserDAO 和 UserDAOImpl: Y{#*;p*I
java代码: 34k>O
$9r4MMs{$
L%{YLl-zf]
/*Created on 2005-7-15*/ dw5"}-D
package com.adt.dao; } snS~kx
GQd[7j[sh
import java.util.List; Dr=$ }Y
]SPuNBsy)
import org.flyware.util.page.Page; :2
:VMIa
1-PlRQs.1
import net.sf.hibernate.HibernateException; (3!6nQj-t
z#P`m,~t0
/** `{
HWk^
* @author Joa k\j_hu
*/ .\ya
publicinterface UserDAO extends BaseDAO { WQiRbb X
5/h-Hr
publicList getUserByName(String name)throws T{`VUS/
r%ebC
HibernateException; OW@)6
FeO1%#2<y
publicint getUserCount()throws HibernateException;
(#O"
bqA`oRb\
publicList getUserByPage(Page page)throws VmQ'
mEi(DW)(
HibernateException; &=n/h5e0t&
%xQ'i4`
} RjO0*$>h
7[mfI?*m
w{2CV\^>5
%0/qb0N&
kTI5CoXzq
java代码: Q3^h
S^p^)
fAmF
TBOg.y]
/*Created on 2005-7-15*/ r%iFsV_
package com.adt.dao.impl; Kz/,V6H:
S^==$TT
import java.util.List; mf{M-(6'
_`^AgRE
import org.flyware.util.page.Page; d6JW"
qz3
Z'
import net.sf.hibernate.HibernateException; chKEGosbF
import net.sf.hibernate.Query; "p|.[d
_O'!C!K6
import com.adt.dao.UserDAO; { gs$pBu
f8N*[by
/** "M /Cl|z
* @author Joa p8)R#QWz9
*/ oaPWeM+
public class UserDAOImpl extends BaseDAOHibernateImpl 5G(dvM-n
Yo'Y-h#
implements UserDAO { |mHf7gCX
oD\t4]?E
/* (non-Javadoc) 2Vf242z_
* @see com.adt.dao.UserDAO#getUserByName @n.n[zb\|
i|AWaG)
(java.lang.String) Aaq%'07ihW
*/ I=<Qpd4
publicList getUserByName(String name)throws i '*!c
n^hkH1vY
HibernateException { >1Hv c7DP
String querySentence = "FROM user in class 1i~q~O,
Z}>F
V~4
com.adt.po.User WHERE user.name=:name";
_(8#
Query query = getSession().createQuery Yk?q \1
B&B:P
(querySentence); .s,04xW\
query.setParameter("name", name); gt(p%~
return query.list(); Do\j _
} .Tq8Qdl
|%ZJN{!R
/* (non-Javadoc) :3D6OBkB
* @see com.adt.dao.UserDAO#getUserCount() YG:^gi
*/ (Sgsy^|N
publicint getUserCount()throws HibernateException { tD}-&"REP
int count = 0; 0!ZaR6
String querySentence = "SELECT count(*) FROM `O0Qtq.
c^pQitPv
user in class com.adt.po.User"; "Ueq
Query query = getSession().createQuery _,aFQ^]'9
P!IA;i
(querySentence); ob2_=hQnC
count = ((Integer)query.iterate().next 4u%AZ<-C}m
+75"Q:I
()).intValue(); .[1 f$
return count; D&uaA-;s
} &S66M2
&oHr]=xA
/* (non-Javadoc) +>*=~R
* @see com.adt.dao.UserDAO#getUserByPage oQmXKV+[v
r nr-wUW@
(org.flyware.util.page.Page) g}R Cjl4
*/ T8|?mVv s
publicList getUserByPage(Page page)throws #5{xWMp/0
KU
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HibernateException { \z FCph4
String querySentence = "FROM user in class c*E7nc)u
\mJR^t
com.adt.po.User"; G"-V6CA[
Query query = getSession().createQuery D86F5HT}}
U\qbr.<
(querySentence); b1i~F45h
query.setFirstResult(page.getBeginIndex()) <8kCmuGlk
.setMaxResults(page.getEveryPage()); LAlX|b
return query.list(); >Ovz;
} 26k~Z}
\$DBtq5=
} WoGnJ0N q
71P. 9Iz
![r)KE=v8I
0)b1'xt',
"9aFA(H6w
至此,一个完整的分页程序完成。前台的只需要调用 er-0i L@
[hg9 0Q6
userManager.listUser(page)即可得到一个Page对象和结果集对象 Kg>B$fBx)
YlG#sBzl
的综合体,而传入的参数page对象则可以由前台传入,如果用 Y%eW6Y#
biS[GyQ
webwork,甚至可以直接在配置文件中指定。 /<$|tp\Rc
SSE,G!@
下面给出一个webwork调用示例: a*D<J}xe
java代码: VBDb K|
<D)@;A
$^^M&[b-
/*Created on 2005-6-17*/ ',WJ'g
package com.adt.action.user; =FIZh}JD
HDzeotD
import java.util.List; @jMo/kO/A
-X7x~x-
import org.apache.commons.logging.Log; !A%
vR\
import org.apache.commons.logging.LogFactory; CVkJMH_
import org.flyware.util.page.Page; ^b|? ?9&
SIR2 Kc0
import com.adt.bo.Result; GeB&S!F
import com.adt.service.UserService; .-&
=\}^2l
import com.opensymphony.xwork.Action; Et-|[ eL
ps,Kj3^T<
/** zZRLFfz<9
* @author Joa {cLWum[SY
*/ Viw,YkC
publicclass ListUser implementsAction{ Je9Z:s[
2~g-k3
privatestaticfinal Log logger = LogFactory.getLog c1+z(NQ3
iiJT%Zq`#
(ListUser.class); P{`fav
PyHL`PZZ
private UserService userService; V/"RCqY4
v*JKLA
private Page page; +,ar`:x&a
,Fkq/h
privateList users; #`%S[)RT
Z+);}>-5
/* (0LA.aBIf
* (non-Javadoc) 'sa)_?Hy
* B= E/|J</
* @see com.opensymphony.xwork.Action#execute() 4Y1^ U{A+
*/ Fec4 #}|
publicString execute()throwsException{ ^z,B}Nz
Result result = userService.listUser(page); <6+B;brh
page = result.getPage(); *9=}f;~
users = result.getContent(); [kr-gV
return SUCCESS; r^rk@W;[
} #EE<MKka
PlA#xnq#
/** 1'TS!/ll];
* @return Returns the page. tq'hiS(b
*/ s!D2s2b9e
public Page getPage(){ fQ!W)>mi
return page; Xg_l4!T_l
} +cmi?~KS*
\vV]fX
/** D5bi)@G7z
* @return Returns the users. eUCBQK
*/ 7iM@BeIf
publicList getUsers(){ Q$`uZ
return users; BSd.7W;cS=
} MzKl=G
09Eg ti.
/** |G6'GTwZD
* @param page 5-({z%:P
* The page to set. &vN!>bR
*/ A(`Mwh+
publicvoid setPage(Page page){ |+sAqx1IF
this.page = page; ax;<idC}
} T5T[$%]6
\j wxW6>
/** p*YV*Arv
* @param users 7MJ\*+T|03
* The users to set. Ujvm|ml
*/ \/Q~C!
publicvoid setUsers(List users){ X#h a*u~U
this.users = users; v6uRzFw
} x00'wY|
E1Q#@*rX>
/** })uyq_nz
* @param userService t&5 Ne ?
* The userService to set. c0&!S-4M
*/ d>zC[]1
publicvoid setUserService(UserService userService){ ""N~##)8
this.userService = userService; 0/7.RpX,.
} u`(yT<>H
} $*_79F2zN
e!w2_6?3
/6y{?0S
$1zWQJd[-
TEj"G7]1$A
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, -*T0Cl.
KZ AF9
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 PX/^*
K~3Y8ca
么只需要: pg_H' 0R
java代码: ^AOJ^@H^>
Uy)pEEu
(47la$CR
<?xml version="1.0"?> jMS>B)'TO
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ( 'dbMH\O
Tl]yl$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ,->5 sJ{U
#NL'r99D/o
1.0.dtd"> G6x'Myg I
&l_}yf"v
<xwork> .~rg#*]^
}K,3SO(:
<package name="user" extends="webwork- 9}fez)m:g0
e6{E(=R[M
interceptors"> seP h%Sa_
1Id"|/b%$
<!-- The default interceptor stack name @"^7ASd%
JdWav!PYm
--> {'{9B
<default-interceptor-ref m,]9\0GUd
]8Xip/uE
name="myDefaultWebStack"/> Clap3E|a
]\}MSo3
<action name="listUser" A
=&`TfXu
(q}LirR
class="com.adt.action.user.ListUser"> }:J-o
<param "K+EZ%~<
\&Bdi6xAy
name="page.everyPage">10</param> 7<B-2g
<result d:_;
d1
kE)R
name="success">/user/user_list.jsp</result> U+E9l?4R
</action> n3-VqYUP
Y5"HKW^
</package> # M!1W5#
7+X~i@#rU
</xwork> |}<Gz+E>
AKk&
HN5,MD[
qFq$a9w|@
WoNY8
8hT
m"'`$ /_
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 +~y>22Zfg
,LmP >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。 ~0?B
6mIK[Qnp
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 d:#tN4y7(
cJTwgm?
tL<.B
w
$`w
p:0X3?IG3
我写的一个用于分页的类,用了泛型了,hoho E2>+V{TF
\.Op6ECV9
java代码: :IfwhI)
x5/&,&m`%
/s=veiH
package com.intokr.util; ~ ^
tp&|*M3
import java.util.List; A%^7D.j
}owl7G3
/** m_`%#$s}
* 用于分页的类<br> 'lu3BQvfh
* 可以用于传递查询的结果也可以用于传送查询的参数<br> )Z['=+s%
* _G25$%/LU
* @version 0.01 Un
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* @author cheng r=54@`O!
*/ SR?(z
public class Paginator<E> { u-mD"
privateint count = 0; // 总记录数 kBoQjOV`
privateint p = 1; // 页编号 %*Uc,V
privateint num = 20; // 每页的记录数 h@(+(fVHrp
privateList<E> results = null; // 结果 -R\dg S3
)E^4U9v),
/** 1Ax;|.KQH
* 结果总数 *0Fz." v
*/ _ u~0t`f~
publicint getCount(){ %k )H7nj
return count; be5N{lPT@;
} %NC/zqPH~
&Vgpv#&Cfx
publicvoid setCount(int count){ g0B%3v
this.count = count; G|8>Q3D
}
~vM99hW
}@tgc?CD
/** jh`[Y7RJO
* 本结果所在的页码,从1开始 uhp.Yv@c
* ?.H]Y&XF
* @return Returns the pageNo. ={N1j<%fh
*/ .V3e>8gw3
publicint getP(){ W}MN-0
return p; ?A*!rW:l;
} BpYxH#4
,wBfGpVb
/** Zzz94`
* if(p<=0) p=1 <1<xSr
* A=p'`]Yld
* @param p \4C[<Gbx$(
*/ u|.7w2
publicvoid setP(int p){ u*,>$(-u
if(p <= 0) xk7Dx}
p = 1; *kYGXT,f]
this.p = p; N#t`ZC&m'
} MtN!Xx
D3P/: 4
/** t4/ye>P &
* 每页记录数量 }<l:~-y|
*/ !@N?0@$/
publicint getNum(){ uN>5Eh&=Pf
return num; C_8_sbZ/
} Q>rr?L`
cY kb3(
/** a
}*i [
* if(num<1) num=1 rPGj+wL5-
*/ /@\R
publicvoid setNum(int num){ BzO,(bd!PI
if(num < 1) N@}h
num = 1; ?2dI8bG
this.num = num; YhS_ ,3E
} ^m&P0
=+ >>l0=_v
/** @h!Z0}dX(
* 获得总页数 , c{ckm
*/ ?h%Jb^#9
publicint getPageNum(){ 150-'Q
return(count - 1) / num + 1; N
fG9a~
} $u yx
ar}-~~h 5
/** >8=lX`9f{
* 获得本页的开始编号,为 (p-1)*num+1 0.w7S6v|&
*/ UOl*wvy
publicint getStart(){ }f?[m&<
return(p - 1) * num + 1; E]GbLU;TH
} A~<!@`NjB
[(5.?
/** `&