Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 p9l&K/
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 mRQ F5W6
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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 5%tIAbGW
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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
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分页支持类: {yspNyOx
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java代码: {d^&$~
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package com.javaeye.common.util; 8V~w3ssz
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import java.util.List; 9RR1$( f
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publicclass PaginationSupport { HnOp*FP
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; sVh!5fby&
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privateList items; B;G|2um:$
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privateint totalCount; `[o^w(l:5@
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privateint[] indexes = newint[0]; S~Nx;sB
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privateint startIndex = 0; of{wZU\J+9
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public PaginationSupport(List items, int LuQ=i`eXx
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totalCount){ nM}X1^PiK"
setPageSize(PAGESIZE); #C!8a
setTotalCount(totalCount); {u9VHAXCf
setItems(items); V3I&0P k
setStartIndex(0); O a-ZeCq
} 9"MC<
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public PaginationSupport(List items, int |y;+xEl6
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totalCount, int startIndex){ M-|4cd]6
setPageSize(PAGESIZE); oSy[/Y44a
setTotalCount(totalCount); +-8uIqZ
setItems(items); 5F
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setStartIndex(startIndex); ;t*45
} xj%h-@o6
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public PaginationSupport(List items, int (A( d]l
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totalCount, int pageSize, int startIndex){ t3U*rr|A
setPageSize(pageSize); =b9?r
setTotalCount(totalCount); npbNUKdz
setItems(items); na8A}\!<
setStartIndex(startIndex); \>9%=32u.
}
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publicList getItems(){ fdp/cwd
return items; >cSc
} Dc BTW+
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publicvoid setItems(List items){ jOE b1
this.items = items; !:e}d+F
} +J+]P\:
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publicint getPageSize(){ :ykQ[d`:|
return pageSize; +s_@964
} B6=8cf"i
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publicvoid setPageSize(int pageSize){ :K2N7?shA
this.pageSize = pageSize; Q1s`d?P/`
} &t%ICz&3
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publicint getTotalCount(){ Ybd){Je"z
return totalCount; *"1]NAz+
} c%i/ '<Afr
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publicvoid setTotalCount(int totalCount){ D97oS!*
if(totalCount > 0){ SDdK5@1O4o
this.totalCount = totalCount; bl}$x/
int count = totalCount / ~?[@KK
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pageSize; >JC.qjA
if(totalCount % pageSize > 0) [ &R-YQ@
count++; 37M7bB0
indexes = newint[count]; QGLfZvTT
for(int i = 0; i < count; i++){ f9OVylm
indexes = pageSize * m}F1sRkdQ
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i; E})PNf;
} C{Aeud #5
}else{ y>Nlj%XH
this.totalCount = 0; .KRh59yg
} D~2,0K
} ?]$.3azO
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publicint[] getIndexes(){ !BK^5,4?--
return indexes; %&e5i
} /Q{Jf+>R>
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publicvoid setIndexes(int[] indexes){ Hhfqb"2on
this.indexes = indexes; 80:na7$)#
} [f-
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publicint getStartIndex(){ c;(}Ih(#
return startIndex; ;k!Ej-(
} rQ~%SUM7
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publicvoid setStartIndex(int startIndex){ SM0=
if(totalCount <= 0) uQpV1o5iA
this.startIndex = 0; _Se>X=
elseif(startIndex >= totalCount) &/a/V
this.startIndex = indexes V&\ZqgDF
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[indexes.length - 1]; gsT%_2>CL
elseif(startIndex < 0) 0=-h9W{zI
this.startIndex = 0; dd98vVj
else{ yK [~(!c5
this.startIndex = indexes !cWKY\lpv
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[startIndex / pageSize]; )RA7Y}e|m
} ]+fL6"OD/2
} ){8^l0b
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publicint getNextIndex(){ ^H&6'A`
int nextIndex = getStartIndex() + ]9b*!n<z
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pageSize; k('2K2P
if(nextIndex >= totalCount) [.3M>,)+-
return getStartIndex(); .,tf[w 71
else +F+jC9j(<
return nextIndex; ]sbu9O ^"f
} #[Ns\%Ri0
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publicint getPreviousIndex(){ ?4gYUEM#
int previousIndex = getStartIndex() - ~~wz05oRG
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pageSize; mxDy!:@=
if(previousIndex < 0) INcJXlv
return0; U_oMR$/Z
else l_QpPo!a
return previousIndex; |bB..b
} b\6w[52m
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} s}/YcUK
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抽象业务类 ~Dgui/r9J
java代码: Sh{odrMj*
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/** ?XW+&!ar
* Created on 2005-7-12 3}Uae#oy
*/ HLTz|P0JZ
package com.javaeye.common.business; 2Ni2Gkf@
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import java.io.Serializable; *i)GoQoB
import java.util.List; &bA;>Lu#|o
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import org.hibernate.Criteria; uw;s](~E
import org.hibernate.HibernateException; H^'EY:|
import org.hibernate.Session; .>h|e_E
import org.hibernate.criterion.DetachedCriteria; VZw( "a*TB
import org.hibernate.criterion.Projections; >;0z-;k6
import 4[rD|
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org.springframework.orm.hibernate3.HibernateCallback; @Q TG
import Z#^2F8,]
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org.springframework.orm.hibernate3.support.HibernateDaoS S@Jl_`<
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upport; Y@;bA=Du}
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import com.javaeye.common.util.PaginationSupport; cUS2*7h
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public abstract class AbstractManager extends N[zI@>x
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HibernateDaoSupport { qlDLZ.
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privateboolean cacheQueries = false; aJIj%Y$
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privateString queryCacheRegion; >8jDW "Ua
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publicvoid setCacheQueries(boolean /WMG)#kw'
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cacheQueries){ 9lOUE
this.cacheQueries = cacheQueries; -/7[_,
} Tcr&{S&o
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publicvoid setQueryCacheRegion(String %xWmzdn
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queryCacheRegion){ Z&J417buk
this.queryCacheRegion = ~5]AXi'e~
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queryCacheRegion; bNIT 1'v
} "eGS~-DVK
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publicvoid save(finalObject entity){ E/AM<eN
getHibernateTemplate().save(entity); }{E//o:Ta
} [xM07%:
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publicvoid persist(finalObject entity){ ~+^,o_hT
getHibernateTemplate().save(entity); rA{h/T"
} _czLKbcF
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publicvoid update(finalObject entity){ EYG&~a>L*
getHibernateTemplate().update(entity); uyAhN
} cS{ l2}E
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publicvoid delete(finalObject entity){ h_y<A@[P}
getHibernateTemplate().delete(entity); ChGwG.-%L
} _v]I6<!5U
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publicObject load(finalClass entity, }L:LcM
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finalSerializable id){ t41\nTZr
return getHibernateTemplate().load -YSn 3=
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(entity, id); GpxGDN3?
} L{
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publicObject get(finalClass entity, |%zhwDQ.
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finalSerializable id){ qWQJ>
return getHibernateTemplate().get xZ4\.K\f]
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(entity, id); V<ODt%
} o{>hOs
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publicList findAll(finalClass entity){ vP&*(WfO)
return getHibernateTemplate().find("from t"RgEH@
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" + entity.getName()); <J`_Qc8C
} {"4t`dM
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publicList findByNamedQuery(finalString AS4m227
q@Q|oB0W$)
namedQuery){ $Q]`+:g*}
return getHibernateTemplate 7e}p:Vfp
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().findByNamedQuery(namedQuery); !.3
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} '90B),c{
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publicList findByNamedQuery(finalString query, 'fK_J}+P
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finalObject parameter){ 7W}~c/ %
return getHibernateTemplate 6jF~zI^
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().findByNamedQuery(query, parameter); r!Mr\
} Q9W*)gBvn
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publicList findByNamedQuery(finalString query, T_YN^za(q
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finalObject[] parameters){ YXD1B`23
return getHibernateTemplate Eb{TKz?
SOP=
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().findByNamedQuery(query, parameters); }3)$aI_
}
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publicList find(finalString query){ t7)Y@gRy
return getHibernateTemplate().find =X% D;2
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(query); _);1dcnR
} ,QG,tf?
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publicList find(finalString query, finalObject Za=<euc7
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parameter){ yd>kJk^~/
return getHibernateTemplate().find Z\dILt:#z
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(query, parameter); Or6'5e?N
} 9';0vrFeM
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public PaginationSupport findPageByCriteria %>24.i"l
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(final DetachedCriteria detachedCriteria){ CGv(dE,G&]
return findPageByCriteria [nG/>Z]W
iW |]-Ba\
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Az0Yt31=
} C5XCy%h
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public PaginationSupport findPageByCriteria m=%W <8[V
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(final DetachedCriteria detachedCriteria, finalint (y(V,kXwa8
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startIndex){ ](8XC_-U'
return findPageByCriteria Uv%"45&7
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(detachedCriteria, PaginationSupport.PAGESIZE, NPf,9c;
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startIndex); @^;\(If2
} &dOV0y_
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public PaginationSupport findPageByCriteria ^Jc~G~x4*
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(final DetachedCriteria detachedCriteria, finalint `o:)PTQNg
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pageSize, #uey1I@"9
finalint startIndex){ &,KxtlR![
return(PaginationSupport) ;39{iU.m
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getHibernateTemplate().execute(new HibernateCallback(){ UbMcXH8=F
publicObject doInHibernate xFyMg&
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(Session session)throws HibernateException { li; P,kg$
Criteria criteria = xnh%nv<v{
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detachedCriteria.getExecutableCriteria(session); n,V`Y'v)
int totalCount = tP3H7Yl!g
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((Integer) criteria.setProjection(Projections.rowCount 4&`66\p;
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()).uniqueResult()).intValue(); ;7 IVg[f
criteria.setProjection Y-9]J(
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(null); ef53~x
List items = Odbjl[>k
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criteria.setFirstResult(startIndex).setMaxResults ~vF.k,
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(pageSize).list(); ^//N-?Fx
PaginationSupport ps = u2Rmp4]
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new PaginationSupport(items, totalCount, pageSize, K-vso4@BJ
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startIndex); 0Fi7|
return ps; 4|Y0$(6o
} ?V7[,I1?
}, true); dC.uK^FuJ
} 9&2kuLp?P
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public List findAllByCriteria(final Gjv'$O2_
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}
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DetachedCriteria detachedCriteria){ % yJs"%
return(List) getHibernateTemplate ,eZ'pxt
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().execute(new HibernateCallback(){ 9k83wACry
publicObject doInHibernate wx57dm+
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(Session session)throws HibernateException { XP(q=Mw
Criteria criteria = kSI,Q!e\
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detachedCriteria.getExecutableCriteria(session); EoOrA@N
return criteria.list(); (tVY
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}
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}, true); Qh{=Z^r
} gu"Agct4
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public int getCountByCriteria(final aC%0jJ<eo
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DetachedCriteria detachedCriteria){ C[x!Lf8'
Integer count = (Integer) g[eI-J+F
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getHibernateTemplate().execute(new HibernateCallback(){ b LxV
publicObject doInHibernate NtA}I)'SWU
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(Session session)throws HibernateException { sL!6-[N
Criteria criteria = rc;| ,\
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detachedCriteria.getExecutableCriteria(session); G=b`w;oL:
return bBDgyFSI<
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criteria.setProjection(Projections.rowCount !\!fd(BN
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()).uniqueResult(); Ke\?;1+
} 63k8j[$
}, true); IAtc^'l#
return count.intValue(); ^Yn6kF
} x^C,xP[#Y;
} ^ qE4:|e
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用户在web层构造查询条件detachedCriteria,和可选的 ls/:/x(5d
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 g/Qr]:;
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PaginationSupport的实例ps。 u`("x5sa
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ps.getItems()得到已分页好的结果集 H9 't;Do
ps.getIndexes()得到分页索引的数组 l+T\DZ
ps.getTotalCount()得到总结果数 %GHHnf%2Z
ps.getStartIndex()当前分页索引 #b{otc)
ps.getNextIndex()下一页索引 LoTq2 /
ps.getPreviousIndex()上一页索引 GLk7#Y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Z0-W%W
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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 WQ6E8t)
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一下代码重构了。 d;'@4NX5+
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我把原本我的做法也提供出来供大家讨论吧: ;GvyL>|-~
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首先,为了实现分页查询,我封装了一个Page类: j)J4[j
java代码: (]iw#m{
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/*Created on 2005-4-14*/ VF6@;5p
package org.flyware.util.page; 5V%K'a(
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/** O>'o; 0
* @author Joa o^>*aQ!7<D
* }TYCF@
*/ SIbQs8h]
publicclass Page { V{a 7@_y
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/** imply if the page has previous page */ Ebp8})P/~
privateboolean hasPrePage; I5 [r-r
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/** imply if the page has next page */ m2 N
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privateboolean hasNextPage; }3vB_0[r
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/** the number of every page */ *h]qh20t
privateint everyPage; /e\}
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/** the total page number */ g]d@X_ &D
privateint totalPage; I.\u2B/?
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/** the number of current page */ kQ4%J,7e4
privateint currentPage; Ij4\* D!
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/** the begin index of the records by the current gS"@P:wYzs
{;z3$/JB
query */ )V9$ P)
privateint beginIndex; 5*4P_q(AxD
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/** The default constructor */ 'kYV}rq;l
public Page(){ 5"@<7/2qI
@.MM-
} NB16O!r
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/** construct the page by everyPage a@m>S$S
* @param everyPage /T_tI R>
* */ X'iki4
public Page(int everyPage){ BHU(Hd
this.everyPage = everyPage; Z.,Pl
} [S$)^>0
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/** The whole constructor */ fzSZ>I0R
public Page(boolean hasPrePage, boolean hasNextPage, I ][8[UZ
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int everyPage, int totalPage, /&ph-4\i
int currentPage, int beginIndex){ A$|> Jt
this.hasPrePage = hasPrePage; Npq=jlj
this.hasNextPage = hasNextPage; ]c$%;!ZE
this.everyPage = everyPage; 6bfk4k
this.totalPage = totalPage; 8/=[mYn`-
this.currentPage = currentPage; \@I.K+hj$
this.beginIndex = beginIndex; 7b
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} .R:eN&Y8y
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/** r+
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* @return if_e$,dh~>
* Returns the beginIndex. >,1'[)_
*/ )[zyvU. J3
publicint getBeginIndex(){ )w/f 'fq
return beginIndex; 62Jn8DwAT
} HlV3rYh
u}#rS%SF*
/** p>R F4
* @param beginIndex mflI> J=g
* The beginIndex to set. `DJIY_{-2
*/ OE:t!66
publicvoid setBeginIndex(int beginIndex){ 8f29Hj+
this.beginIndex = beginIndex; E1VCm[j2
} ?F`lI""E
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/** fpoH7Jd V
* @return Kji}2j'a
* Returns the currentPage. zJ &qR
*/ +R*4`F:QJQ
publicint getCurrentPage(){ j*+r`CX
return currentPage; r$0=b
-
} TTqOAo[-Z
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/** uw]e$,x?
* @param currentPage PQf FpmG
* The currentPage to set. L@G)K
*/ q^12Rj;H
publicvoid setCurrentPage(int currentPage){ tkJ/h<
this.currentPage = currentPage; : l]>nF4
} ?g<*1N?:
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/** EB\z:n5
* @return WqTW@-}I D
* Returns the everyPage. Q~*A`h#
*/ ((X"D/F]
publicint getEveryPage(){
# &M
return everyPage; nP0}vX)<
} w7%N=hL1
s/A]&!`
/** R~c(^.|r
* @param everyPage J-X5n 3I&
* The everyPage to set. Vy(lyD<6
*/ t`DUY3>36
publicvoid setEveryPage(int everyPage){ sCnZ\C@u
this.everyPage = everyPage; Mzb_o2^(
} O;,k~
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/** {CGk5` g~
* @return cHR }`U$
* Returns the hasNextPage. KY_qK)H
*/ .h*&$c/l
publicboolean getHasNextPage(){ ` D4J9;|;]
return hasNextPage; SX
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} <v{jJ7w
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/** OTV)#,occ
* @param hasNextPage :I&iDS>u1
* The hasNextPage to set. /CZOO)n
*/ Pu*st=KGB
publicvoid setHasNextPage(boolean hasNextPage){ t+h"YiT
this.hasNextPage = hasNextPage; J(l6(+8
} @MN>ye'T
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/** Y ,}p
* @return _abVX#5<
* Returns the hasPrePage. [NKWudq
*/ ?X:RrZ:/
publicboolean getHasPrePage(){ wvq<5gy}
return hasPrePage; _Juhl^LM;
} *w%;$\^
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/** Th!S?{v
* @param hasPrePage =jG3wf*
* The hasPrePage to set. |E?%Cj^W
*/ neZ_TT/3K
publicvoid setHasPrePage(boolean hasPrePage){ )p!dqlK
this.hasPrePage = hasPrePage; esLY1c%"/
} m\~[^H~g
xK_$^c.
/** :z"Uw*
* @return Returns the totalPage. E8-p
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* "#m*`n
*/ w=f8UtY9@A
publicint getTotalPage(){ ^Xb!dnT.*a
return totalPage; JP@UvDE|
} mKn[>M1
5-&P4
/** | _S9U|
* @param totalPage b,K1EEJ
* The totalPage to set. As>po+T*
*/ -eNi;u
publicvoid setTotalPage(int totalPage){ -><_J4
this.totalPage = totalPage; T]i~GkD\
} 7tr.&A^c
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} ^Cak/5^K
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 h?CNChRJs
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个PageUtil,负责对Page对象进行构造: 0\gE^=o[
java代码: w$t2Hd
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/*Created on 2005-4-14*/ RhDa`kV%t
package org.flyware.util.page; (8>k_
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import org.apache.commons.logging.Log; eM~i (]PY
import org.apache.commons.logging.LogFactory; UcK!v*3E
^^ ?ECnpcU
/** 979L] H#
* @author Joa e%f8|3<6
* f|apk,o_
*/ SD697L9
publicclass PageUtil { o@>5[2b4
CiMN J
privatestaticfinal Log logger = LogFactory.getLog y\%4Dir
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(PageUtil.class); Ao]F_hZ
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/** "5YsBih
* Use the origin page to create a new page )<~b*^kl\
* @param page fh 2Pn!h+
* @param totalRecords g1}RA@9
* @return 7"S|GEs:
*/ kPxrI=
publicstatic Page createPage(Page page, int {fS/ZG"5<t
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totalRecords){ QVFa<>8/md
return createPage(page.getEveryPage(), JEAqSZak#
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page.getCurrentPage(), totalRecords); RSkpf94`
} "%Rx;xw|
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/** i\PN
* the basic page utils not including exception j5RMS V
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handler b>waxQxjS
* @param everyPage #}vcffgZ
* @param currentPage Cf10 ud
* @param totalRecords BzgDhDj
* @return page ?Dfgyz
*/ *X)OdU
publicstatic Page createPage(int everyPage, int B)c.`cfr*\
#6YNgJNk
currentPage, int totalRecords){ a-kU?&*
y
everyPage = getEveryPage(everyPage); !WIL|\jbh
currentPage = getCurrentPage(currentPage); ~o8$/%Oeb/
int beginIndex = getBeginIndex(everyPage, 3*'!,gK~[
4e5Ka{# <
currentPage); 00$W>Gr
int totalPage = getTotalPage(everyPage, -MU^%t;-
CE+\|5u
W
totalRecords); vu*08<M~i|
boolean hasNextPage = hasNextPage(currentPage, Uh7kB`2
!X,=RR`zT
totalPage); q=
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boolean hasPrePage = hasPrePage(currentPage); ?^6RFbke+
K1 $Z=]a+
returnnew Page(hasPrePage, hasNextPage, \"uR&D
everyPage, totalPage, T0Gu(c`1d
currentPage, *=ALns?y
apYf,"|9
beginIndex); [NuayO3
} uH7u4f1Q
yqAw7GaBN
privatestaticint getEveryPage(int everyPage){ (yZ^Y'0
return everyPage == 0 ? 10 : everyPage; $60+}B`m
} :oZ30}
Lu<'A4Q1
privatestaticint getCurrentPage(int currentPage){ kdF#Nm
return currentPage == 0 ? 1 : currentPage; `5gcc7b
} x JepDCUJ>
T{ojla(
privatestaticint getBeginIndex(int everyPage, int ]6(NeS+
A\?O5#m:$
currentPage){ ;,F}!R
return(currentPage - 1) * everyPage; *W0`+#Dcv
} DsP+#PX
Nlo*vu
privatestaticint getTotalPage(int everyPage, int UZdpKi@
38f9jF%7j
totalRecords){ _@HMk"A
int totalPage = 0; _E?(cWC
"V^(i%E;
if(totalRecords % everyPage == 0) 'g$|:bw/
totalPage = totalRecords / everyPage; V862(y
else _El=M0
totalPage = totalRecords / everyPage + 1 ; 0lW}l9}'-
udw5A*Ls
return totalPage; ,qC_[PUT
} Qn6&M
j:fL_1m
privatestaticboolean hasPrePage(int currentPage){ _w'4f )7
return currentPage == 1 ? false : true; Ye,E7A*L
} Z*leEwgz
<Z}2A8mjY
privatestaticboolean hasNextPage(int currentPage, @90)
>
^D10Nf*
int totalPage){ ]ErAa"?
return currentPage == totalPage || totalPage == :vm*miOF
#2n>J'}
0 ? false : true; :r!nz\%WW
} xr o
7$/ O{GBJ
k%.IIVRx
} fRq2sK;+
k ELV]iWb
Wb^YqqE
OI1&Z4Lx
t\'URpa+5%
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。 3VcG
/rf
I]zCsT.
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 gx#TRp}-
:xv"m
{8+
做法如下: {E>kFeg
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 yht_*7.lM
;i\i+:=
的信息,和一个结果集List: 9.>v
;:vL
java代码: L0Xb^vx}m
T?Hs_u{
/}(w{6C
/*Created on 2005-6-13*/ 5{j1<4zxR
package com.adt.bo; [1l ,I[
8/]5h%
import java.util.List; A LKU
mKn:EqA
import org.flyware.util.page.Page; yn`H }@`k
@VVBl I
/** /\OjtE
* @author Joa X 5pp8~
*/ #dU-*wmJ
publicclass Result { -2bu`oD
`
_0ep[r
private Page page; YJF!_kg.
>u~
l_?
private List content; :+Y+5:U]
D1#fy=u69|
/** 1VH7z
* The default constructor 1Hk`i%
*/ uq{w1O5
public Result(){ 11O^)_|c
super(); 1iig0l6\m
} <`n T+c
jl%27Ld
/** a%V6RyT4qW
* The constructor using fields t4~Bn<=
* &n91f
* @param page c|IH|y
* @param content Z!v)zH\
*/ gT?:zd=;
public Result(Page page, List content){ X\V1c$13CK
this.page = page; L>Y%$|4
this.content = content; ]?-8[v~{C
} [,yoFm%"
DTH;d-Z
/** w<*6pPy
* @return Returns the content. SI^!e1@M[
*/ l'y)L@|Qrh
publicList getContent(){ ?45bvkCT
return content; 2tMe# V
} 0z.oPV@
sWa`-gc
/** ko2 ?q
* @return Returns the page. luY#l!mx3
*/ <y7nGXzLK
public Page getPage(){ 7vF+Di(B
return page; \u9l4
} ViKN|W>T
M&wf4)*%0+
/** *QH@c3vUe\
* @param content 8{^zXJi]m
* The content to set. dtTQY
*/ xU6)~ae`JW
public void setContent(List content){ DQui7dr)l
this.content = content; h/?$~OD
} I($0&Y\De
ga%gu9
/** 8Q d *OO
* @param page o9*}>J<+RQ
* The page to set. 6QO[!^lY
*/ z10J8Ms'
publicvoid setPage(Page page){ 'I^3r~_
this.page = page; pMndyuoJl
} KxhMPvN'
} # 3UrGom
n
W:P"L
|KY6IGcqV
sVWOh|O[W
_c$l@8KS^
2. 编写业务逻辑接口,并实现它(UserManager, 3)cH\gsg9
AAuH}W>n
UserManagerImpl) >BFUts%
java代码: }$
C;ccWL
YS],o'T
}w&W\g+E$
/*Created on 2005-7-15*/ w=JO$7
package com.adt.service; icS%])3LF
^__';! e
import net.sf.hibernate.HibernateException; V7DMn@Ckw
2 8>
import org.flyware.util.page.Page; uC$!|I
lZ gX{
import com.adt.bo.Result; Z{XF!pS%H
5!-+5TJI
/** ZP-^10
* @author Joa >L4q>S^v
*/ 5y^I~"_i
publicinterface UserManager { [A\DuJx
=^ZDP1h/}
public Result listUser(Page page)throws IE]? WW5
<<WqL?8W
HibernateException; ^-nL!>FYY
c`,'[Q5(O
} U-+o6XX
W=G8l%
%/; *Ewwb
qL2!\zt>g
<Fo~|Nh|
java代码: 7up~8e$ _
T:/mk`>
{gT4Oq__
/*Created on 2005-7-15*/ 7!sR%h5p
package com.adt.service.impl; ly9tI-E
;}B6`v
import java.util.List; S/,)X
?*AhGza/
import net.sf.hibernate.HibernateException; .o#A(3&n
nQ +$
import org.flyware.util.page.Page; v]h^0WU
import org.flyware.util.page.PageUtil; 3le$0f:O
GD-L0kw5
import com.adt.bo.Result; 9z#z9|hj)3
import com.adt.dao.UserDAO; N++ ;}j
import com.adt.exception.ObjectNotFoundException; E%%iVFPX
import com.adt.service.UserManager; utzf7?nIS
WBN3:Y7
/** @6"+x
* @author Joa /$NR@56
\
*/ >BWe"{ ;
publicclass UserManagerImpl implements UserManager { l~Hu#+O
i"`N5
private UserDAO userDAO; :lU#Dm]
0}mVP
/** `(uN_zvH
* @param userDAO The userDAO to set. J.(mg
D
*/ <s=i5t
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publicvoid setUserDAO(UserDAO userDAO){ DFMf"_p
this.userDAO = userDAO;
%w#z
} H-iCaXT
{zIcEN$ ~
/* (non-Javadoc) NG5k9pJ
* @see com.adt.service.UserManager#listUser s|vx2-Cu]
tP1znJh>y
(org.flyware.util.page.Page) }IRD!
*/ .QW@rV:T
public Result listUser(Page page)throws }D]y-BbA.
* ,Le--t
HibernateException, ObjectNotFoundException { PR3i}y>
int totalRecords = userDAO.getUserCount(); 6o.Dgt/f
if(totalRecords == 0) ntxaFVD
throw new ObjectNotFoundException Nt,:`o |
IOddu2.(
("userNotExist"); 0" F\V
page = PageUtil.createPage(page, totalRecords); %bp'`B=
List users = userDAO.getUserByPage(page); ^U9b)KA
returnnew Result(page, users); HDi_|{2^
} "cwvx8un
MX"M2>" pT
} GJ\bZ"vDo
*+TO% {4
h$]nfHi_Q
14`S9SL{V
$sFqMy
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 # AH gY.
l0r^LK$
询,接下来编写UserDAO的代码: B{K_?ae!
3. UserDAO 和 UserDAOImpl: r ?<?0j
java代码: fQxlYD'peb
Z|B`n
SzH
Gs/G_E(T
/*Created on 2005-7-15*/ ,(B/R8ZF~
package com.adt.dao; emHaZhh
p
~pl|
import java.util.List; =5O&4G`}
:z`L)
import org.flyware.util.page.Page; W0S\g#
XnKf<|j6k
import net.sf.hibernate.HibernateException; [:/mjO K
zmg
:Z p=
/** gm$<U9L\v
* @author Joa RF
[81/w]
*/ G;e)K\[J
publicinterface UserDAO extends BaseDAO { HggINMG
\0;EHB
publicList getUserByName(String name)throws TU1W!=Z
734H{,~
HibernateException; ~H4Tr[8a
QsPZ dC
publicint getUserCount()throws HibernateException; -sx=1+\nf
.7HEI;4
publicList getUserByPage(Page page)throws WM0-F@_
D1V^DbUm_
HibernateException; ;ykX]5jGh
bSW~hyI w
} 8w ]'U
2]5ux!Lqln
|[@v+koq
xf;Tk
**]=!W
java代码: V8G.KA "
~3$:C#"Dl
8aY}b($*ZI
/*Created on 2005-7-15*/ m[%P3
package com.adt.dao.impl; 7WHq'R{@
!]MGIh#u
import java.util.List; &S[>*+}{+
z
J V>;
import org.flyware.util.page.Page; G)gPL]C0
BSY7un+`:
import net.sf.hibernate.HibernateException; b~;M&Y
import net.sf.hibernate.Query; {tuGkRY2~
UAds$9
import com.adt.dao.UserDAO; hM[I}$M&O
1`9'.w+r
/** }0Fu
* @author Joa d&X
<&)a7
*/ SpMHq_MLM
public class UserDAOImpl extends BaseDAOHibernateImpl 36d6KS 7
yW;]J87*
implements UserDAO { lrmz'M'
W"g@*B'|
/* (non-Javadoc) 'kekJ.wJ;
* @see com.adt.dao.UserDAO#getUserByName 8*sP
Sr-!-eC
(java.lang.String) T9AFL;1
*/ 8ZNwo
publicList getUserByName(String name)throws qSQsY:]j0
t x1(6V&l;
HibernateException { zLjQ,Lp.I
String querySentence = "FROM user in class H,)2Ou-Wn
J6J;
!~>_
com.adt.po.User WHERE user.name=:name"; (X|lK.W y
Query query = getSession().createQuery npcL<$<6X
`o%Ua0x2
(querySentence); 6z5?9I4[
query.setParameter("name", name); ~./M5P!\
return query.list(); N
lB%Qu
} b|U3\Fmc
b(_PV#@$
/* (non-Javadoc) 5xc-MkIRL
* @see com.adt.dao.UserDAO#getUserCount() `IK3e9QpcA
*/ b@[\+P] "
publicint getUserCount()throws HibernateException { ?r R,
h{~
int count = 0; H?j}!JzAC
String querySentence = "SELECT count(*) FROM -l$-\(,M`#
I_'0!@Nn7
user in class com.adt.po.User"; jxZd
=%7Q
Query query = getSession().createQuery }#E~XlX^
%loe8yt
(querySentence); \)BDl
count = ((Integer)query.iterate().next ANd#m9(x
vUgo)C#<
()).intValue(); lLZ?&z$
return count; !{4bC
} tkEup&
=)2!qoE
/* (non-Javadoc) mTZgvPJ!
* @see com.adt.dao.UserDAO#getUserByPage I@YX-@&7
PxgLt2dXa
(org.flyware.util.page.Page) ,8@U-7f,
*/ *Ui>NTl
publicList getUserByPage(Page page)throws XLFo"f
E#,n.U>#)
HibernateException { B1 [O9 U:
String querySentence = "FROM user in class G `JXi/#`
2_;3B4GDF
com.adt.po.User"; .8Gmy07
Query query = getSession().createQuery G
4C 7
i)+2?<]
(querySentence); +FYhDB~m
query.setFirstResult(page.getBeginIndex()) QfsTUAfR
.setMaxResults(page.getEveryPage()); e[J0+
x#;r
return query.list(); 8}Su7v1
} }P"JP[#E\
#'Lt_Yf!
} =]F15:%Zq
\B
D'"
qGKQrb,K
FrD,)Ad8Q
ahm@ +/2
至此,一个完整的分页程序完成。前台的只需要调用 2~SjRIp Uw
j!QP>AM|`
userManager.listUser(page)即可得到一个Page对象和结果集对象 vq*)2.
}_o!fV
的综合体,而传入的参数page对象则可以由前台传入,如果用 `K\(I#z
H He~OxWg
webwork,甚至可以直接在配置文件中指定。 dtUt2r)6L;
k{j (Gb2sp
下面给出一个webwork调用示例: D3-H!TFpDb
java代码: 4)~GHb
i:,37INMt
[l X3":)
/*Created on 2005-6-17*/ -(+/u .
package com.adt.action.user; @~`2Lo/
QyX ?
import java.util.List; Kly`V]XE
&d^u$Y5
import org.apache.commons.logging.Log; \i$WXW]|
import org.apache.commons.logging.LogFactory; p*Hbc|?{Q&
import org.flyware.util.page.Page; X?Mc"M
bol#[_~
import com.adt.bo.Result; ]o\y(!
import com.adt.service.UserService; YPqp#X*
import com.opensymphony.xwork.Action; 1?bX$$yl;
*$o{+YP
/** xYCX}bksh
* @author Joa NHL{.8L{
*/ ['rqz1DL5
publicclass ListUser implementsAction{ y #Xq@
|lhVk\X
privatestaticfinal Log logger = LogFactory.getLog SmYY){AQ/
BKQI|i
(ListUser.class); -wjvD8fL
UP}5E h
private UserService userService; yp:_W@
ONw;NaE,
private Page page; jPf*qe>U
fUgI*V
privateList users; QR;E>eEq
'Nbae-pf
/* O[[#\BL
* (non-Javadoc) |4s`;4c&
* ^#VyI F3q
* @see com.opensymphony.xwork.Action#execute() gr")Jw7
*/ jTJ]: EN
publicString execute()throwsException{ Z;#Ei.7p|
Result result = userService.listUser(page); -6KGQc}U
page = result.getPage(); ki^c)Tqn
users = result.getContent(); ymLhSF][
return SUCCESS;
uT??t=vb
} |Skk1#
9ZEF%&58Y
/** //}[(9b'\
* @return Returns the page. /U#{6zeM[,
*/ JS<4%@
public Page getPage(){ d= -/'_'
return page; $6XCHVx
} N3Jfp3_b@
zp2IpYQ,3
/** !`G7X
* @return Returns the users. gB\KD{E
*/ IP` ;hC
publicList getUsers(){ N +9`'n^x
return users; 1cyX9X
} /M-%]sayj
Q-!a;/
/** a
N| MBX;
* @param page :>.~"uWo{
* The page to set. 3P!Jw7e
*/ 1Yy5bg6+E
publicvoid setPage(Page page){ E(e'qL
this.page = page; iG1vy'J#o
} ncluA~ 8
/?jAG3"
/** J['paHSF
* @param users &\$l%icuo
* The users to set. &r6VF/
*/ %jK-}0Tu
publicvoid setUsers(List users){ c D+IMlT
this.users = users; `V@{#+X
} u $N2uFc
c%aY6dQG&%
/** rlvo&(a
* @param userService T6|zT}cb
* The userService to set. CqUK[#kW(
*/ a(X?N.w
publicvoid setUserService(UserService userService){ p
AzPi
this.userService = userService; ;2vHdN
} `um#}ify#
} LX e {
@'DfNka
RpE69:~PV
)POuH*j
mJu;B3@
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Y#_,Ig5.
J 3fcnI
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 'Pudy\Ab
xS` %3+|
么只需要: bmEo5f~C!
java代码: {|%N
%v\0Dm+A
;%Jw9G\h
<?xml version="1.0"?> |\j'Z0
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork j(!M
#5kQn>R
1.0//EN" "http://www.opensymphony.com/xwork/xwork- :J-@+_J
FrO)3 1z
1.0.dtd"> 0+0+%#?
e g#.f`
<xwork> u0^:
XwZ!
E0^~i:Mk
<package name="user" extends="webwork- *r)/.rK_
E8WOXoP(
interceptors"> LoLmT7
8oG0tX3i
<!-- The default interceptor stack name 8H3|i7.1h
@eN x:}
--> )eNR4nF
<default-interceptor-ref maLKUSgo
uYlC*z{
name="myDefaultWebStack"/> jRS0(8
/i$
mIj`
<action name="listUser" {T
Z7>k
V+X>t7.Q
class="com.adt.action.user.ListUser"> 2JZf@x+}
<param ;}{%|UAsx
V?v,q'? $
name="page.everyPage">10</param> C`3}7qi|C
<result 2/qP:3)
"#2z
'J
name="success">/user/user_list.jsp</result> S*6P=O*
</action> uh3%}2'P
G}CzeLw
</package> Cs7YD~,
6~sb8pK.=
</xwork> A1:<-TF6^p
, gk49z9
w1/pwzn
U7.3`qd"
~]DGf(
V<AT"vU[
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 3qPj+@
j0!Z 20
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。 m]BxGwT=m
A^2VH$j]+
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 "W;GvI
C)`k{(-{
n4+l,~
0.C y4sH'
-
*!R
我写的一个用于分页的类,用了泛型了,hoho y~An'+yBa
v'7,(.E
java代码: k'X
v*U
z iR}
|BnjT*_9
package com.intokr.util; s_-G`xT>{
$*^Ms>Pa_
import java.util.List; R+FBCVU&TJ
D(D:/L8T,
/** Rz1&(_Ps
* 用于分页的类<br> <\GP\G
* 可以用于传递查询的结果也可以用于传送查询的参数<br>
2J
=K\ L
* LFob1HH*8
* @version 0.01 9D++SU2:}
* @author cheng )f9f_^;
*/ X>j% y7v
public class Paginator<E> { O emi }
privateint count = 0; // 总记录数 `:!mPNW#
privateint p = 1; // 页编号 t\E#8
privateint num = 20; // 每页的记录数 %geiJ z
privateList<E> results = null; // 结果 q?g4**C
:l8n)O3
/**
yTwv2l;U
* 结果总数 r7/y'Y]O
*/
@dQIl#
publicint getCount(){ I.TdYSB
return count; Y;d$x}dh
} e.jrX;;$!&
X[:Hp`_$
publicvoid setCount(int count){ ^AtAfVJN0
this.count = count; )#zc$D^U
} cS/\&%7u
xal+buOiP
/** z=B*s!G
* 本结果所在的页码,从1开始 $^?"/;8P5
* %KK6}d#
* @return Returns the pageNo. {A]"/AC
*/ 72R|zR
publicint getP(){ ik)T>rYg0
return p; ya3A^&:
} bmVksi2b
0gw0
/** nS)U+q-x&o
* if(p<=0) p=1 =.O8G=;DOA
* DZ -5A
* @param p HtB>#`'
*/ 0]=|3-n
publicvoid setP(int p){ K>X#,lE-
if(p <= 0) Ac}+Uq
p = 1; Ecp]fUQK
this.p = p; Y~#m-y
} 4Ei*\:
=mxG[zDtQ
/** XQ]no aU
* 每页记录数量 &^Q-:Kxs8
*/ >%5Ld`c:SD
publicint getNum(){ @ofivCc<%
return num; .6aC2A]es
} n@ lf+
, f{<
/** WzZ<ZCHm
* if(num<1) num=1 @S\!wjl]C
*/ Ya{$:90(4
publicvoid setNum(int num){ H)z}6[`
if(num < 1)
4Ra
num = 1; 2 %UzCK
this.num = num; "C %<R
} G(W/.*
b{JcV
/** |`[0U
* 获得总页数 ,Bax0p
*/ tIfA]pE
publicint getPageNum(){ 3*x_S"h
return(count - 1) / num + 1; ")m0{
} p&dpDJ?d:=
\Fg%V>
/** dPZrX{ c
* 获得本页的开始编号,为 (p-1)*num+1 NQ~keN
*/ 5e=9~].7
publicint getStart(){ Hc^q_{}"
return(p - 1) * num + 1; 4{4VC"fa
} y "6;O 0
I^S
gWC
/** 0'q&7
MV
* @return Returns the results. E{x<P0 ;
*/ `L# pN5
publicList<E> getResults(){ KBJ%$OQV
return results; ScOiOz:Ha
} v,bCj6
6Hoc F/Ye
public void setResults(List<E> results){ Gy 0 m
this.results = results; bQd'objpY
} Ug(;\*yg
A)6xEeyR
public String toString(){ WjLy7&
StringBuilder buff = new StringBuilder :"QR;O@
[Z~h!}
(); Q(v*I&k
buff.append("{"); W;%$7&+0
buff.append("count:").append(count); `o|Y5wQ@
buff.append(",p:").append(p); <% #Dwo}
buff.append(",nump:").append(num); xVYy`_|
buff.append(",results:").append fNR2(8;}
q,S[[{("
(results); -;]m4R)z
buff.append("}"); KA~eOEjM
return buff.toString(); LF6PKS
} CVUA7eG+
*Rm"3S
} ws}cMX]*
Xa o*h(Q@L
WEy$SN+P