Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 "r{
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 KR4 RIJZ_t
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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 MP 8s}
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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 U3c !*i
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分页支持类: Z:MU5(Te
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java代码: QV%eTA
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package com.javaeye.common.util; lGX_5R
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import java.util.List; FEg&EYI
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publicclass PaginationSupport { z* :.maq
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publicfinalstaticint PAGESIZE = 30; aw0xi,Jz
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privateint pageSize = PAGESIZE; *:,7
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privateList items; r\{; ~V
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privateint totalCount; C
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privateint[] indexes = newint[0]; .aR$ou,7
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privateint startIndex = 0; B3Esfk
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public PaginationSupport(List items, int UBy:W^\g
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totalCount){ JSiLG0
setPageSize(PAGESIZE); QGd"Z lQ
setTotalCount(totalCount); '^M3g-C[Jg
setItems(items); !Lj+&D|z
setStartIndex(0); [k6 5i
} })r[qsv
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public PaginationSupport(List items, int E)l@uPA'1
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totalCount, int startIndex){ Rs%6O|u7
setPageSize(PAGESIZE); Wj.
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setTotalCount(totalCount); ~x}=lK N
setItems(items); .:s**UiDR
setStartIndex(startIndex); X*C4NF0
} F%QVn.
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public PaginationSupport(List items, int %S4pkFR
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totalCount, int pageSize, int startIndex){ CpICb9w
setPageSize(pageSize); )<jT;cT!&
setTotalCount(totalCount); $PNIuC?=
setItems(items); kQm\;[R
setStartIndex(startIndex); TXQY&7
} Kth^WHL
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publicList getItems(){ #r)c@?T@j
return items; "ealYveu
} P/FO, S-V
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publicvoid setItems(List items){ H\<C@OkJS}
this.items = items; nZM|8
} yf7p0;$?
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publicint getPageSize(){ ';!02=-@
return pageSize; 5lC "10
} GVp2|\-L
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publicvoid setPageSize(int pageSize){ K]q OLtc
this.pageSize = pageSize; }3!.e
} PV%7m7=x
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publicint getTotalCount(){ R3$eq
)
return totalCount; 2$? )VXtw
} =lG5Kc{B
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publicvoid setTotalCount(int totalCount){ 0Q5ua`U
if(totalCount > 0){ -K)P|'-?m
this.totalCount = totalCount; g=:C/>g
int count = totalCount / `7|v
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pageSize; CtA0W\9w5a
if(totalCount % pageSize > 0) 3u8H F-
count++; L+s,,k
indexes = newint[count]; Os1(28rl
for(int i = 0; i < count; i++){ /5_!Y>W
indexes = pageSize * RxkcQL/Le
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} 9oY%v7
}else{ h7
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this.totalCount = 0; p9 |r y+t
} Rj%q)aw'
} }o?@
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publicint[] getIndexes(){ 8\t~*@"
return indexes; mY3x
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} m`-{ V<(M
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publicvoid setIndexes(int[] indexes){ c X553&
this.indexes = indexes; C
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} i3>7R'q>
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publicint getStartIndex(){ Zcv1%hI
return startIndex; e?G] fz
} ?+b )=Z
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publicvoid setStartIndex(int startIndex){ 6P!M+PO
if(totalCount <= 0) mg*[,_3q33
this.startIndex = 0; z.pP~he
elseif(startIndex >= totalCount) W04-D
this.startIndex = indexes t*^Q`V wQ
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[indexes.length - 1]; nYMdYt04sl
elseif(startIndex < 0) eEQ
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this.startIndex = 0; 3m?3I2k
else{ t8 #&bUX
this.startIndex = indexes X'WbS
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[startIndex / pageSize]; q!9SANTx
} Ry0n_J:7
} zrG&p Z
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publicint getNextIndex(){ Q5/".x^@
int nextIndex = getStartIndex() + 2bfKD'!aH
4 ?,N;Q
pageSize; +=^10D
if(nextIndex >= totalCount) a4L8MgF&$-
return getStartIndex(); $v+Q~\'
else N'!a{rF
return nextIndex;
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} aDTNr/I
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publicint getPreviousIndex(){ {(AYs*5
int previousIndex = getStartIndex() - 'ac %]}`-
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pageSize; 9dr\=e6) C
if(previousIndex < 0) z'MOuz~Y
return0; u:3~Ius
else zVYX#- nv
return previousIndex; sC48o'8(
} AY{caM
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} Id(L}i(X
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抽象业务类 @]t} bF]
java代码: ;zIAh[z
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/** uMtq4.
* Created on 2005-7-12 sME3s-
*/ U`D/~KJ{Y
package com.javaeye.common.business; N)03{$WM
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import java.io.Serializable; >Q#_<IcI
import java.util.List; lzN\~5a}
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import org.hibernate.Criteria; fn(KmuNA
import org.hibernate.HibernateException; |[;9$Vn
import org.hibernate.Session; +HQX]t:Y
import org.hibernate.criterion.DetachedCriteria; lO9ML-8C1
import org.hibernate.criterion.Projections; 5\V>Sj(
import f+j\,LJ
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org.springframework.orm.hibernate3.HibernateCallback; D|@*HX@_Xp
import )'KkO$^&
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org.springframework.orm.hibernate3.support.HibernateDaoS 61HU_!A8S
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upport; \L-o>O
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import com.javaeye.common.util.PaginationSupport; D$d8u=S
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public abstract class AbstractManager extends nxkbI:+t
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HibernateDaoSupport { -uXf?sTV
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privateboolean cacheQueries = false; *Fb]lM7D
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privateString queryCacheRegion; @k>}h\w
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publicvoid setCacheQueries(boolean 9}p?h1NrY
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cacheQueries){ \3LP@;Phn
this.cacheQueries = cacheQueries; `+[Ct08
} I{U7BZy
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publicvoid setQueryCacheRegion(String D]\of#%T
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queryCacheRegion){ V6P2W0m
this.queryCacheRegion = _o/LFLq
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queryCacheRegion; =VFi}C/
} S<H2e{~
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publicvoid save(finalObject entity){ jT>G8}h
getHibernateTemplate().save(entity); vg[A/$gLM
} Zvz Zs
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publicvoid persist(finalObject entity){ AI0YK"c?
getHibernateTemplate().save(entity); m r"b/oM{
} tBC`(7E}
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publicvoid update(finalObject entity){ lKWe=xY\B
getHibernateTemplate().update(entity); u0 myB/`
} 9+H C!Uot
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publicvoid delete(finalObject entity){ /j46`F
getHibernateTemplate().delete(entity); ]r|sU.Vl
} Z;Q2tT/F
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publicObject load(finalClass entity, uF,F<%d
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finalSerializable id){ wV8_O)[
return getHibernateTemplate().load 3m%oXT
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(entity, id); n-zAkKM
} x7\b-EC
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publicObject get(finalClass entity, O(x1Ja,&
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finalSerializable id){ 3-x ;_
return getHibernateTemplate().get *\Z9=8yK
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(entity, id); K#Ia19au5
} >T84NFdz+
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publicList findAll(finalClass entity){ NULew]:5
return getHibernateTemplate().find("from |i_+b@Lul
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" + entity.getName()); )Fk*'6
} by07l5
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publicList findByNamedQuery(finalString ?APzb4f^W
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namedQuery){ DO*rVs3'p[
return getHibernateTemplate M3q%(!2
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().findByNamedQuery(namedQuery); bu0i#
} atr0hmQ
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publicList findByNamedQuery(finalString query, 0O>T{<
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finalObject parameter){ rhff8C//'
return getHibernateTemplate D6+^Qmu"p
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().findByNamedQuery(query, parameter); F*u"LTH
} B&fH
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publicList findByNamedQuery(finalString query, L%S(z)xX3
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finalObject[] parameters){ -S\gDB bb
return getHibernateTemplate HxUJ 0Q
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().findByNamedQuery(query, parameters); P^(uS'j)+
} \_io:{M
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publicList find(finalString query){ g'X{
return getHibernateTemplate().find {L'uuG\9U
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(query); B*Z}=$1j
} osM[Xv
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publicList find(finalString query, finalObject +{~cX]|
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parameter){ ^%5;Sc1V
return getHibernateTemplate().find _tlr8vL
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(query, parameter); d+qeZGg^A
} /,d]`N!
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public PaginationSupport findPageByCriteria f;D(X/"f]
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(final DetachedCriteria detachedCriteria){ vzX%x ul
return findPageByCriteria &s#O iF8
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); .R^R32ln
} QXI#gA
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public PaginationSupport findPageByCriteria mX/'Fta
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(final DetachedCriteria detachedCriteria, finalint \B4f5L8k
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startIndex){ ppuJC'GW
return findPageByCriteria Y sDai<
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(detachedCriteria, PaginationSupport.PAGESIZE, sWyx_
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startIndex); 'QSj-
} =Q,D3F
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public PaginationSupport findPageByCriteria @Os0A
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(final DetachedCriteria detachedCriteria, finalint 8\F|{vt#
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pageSize, uS<og P
finalint startIndex){ qWU59:d^{
return(PaginationSupport) y@h
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getHibernateTemplate().execute(new HibernateCallback(){ QVF561Yz
publicObject doInHibernate AvVPPEryal
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(Session session)throws HibernateException { q*K[?
Criteria criteria = v4qpE!W27~
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detachedCriteria.getExecutableCriteria(session); i,zZJ=a$
int totalCount = H 'IxB[
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((Integer) criteria.setProjection(Projections.rowCount C).+h7{nd
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()).uniqueResult()).intValue(); |H(i)yu"5'
criteria.setProjection # uy^AC$
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(null); \#v(f2jPF
List items = *:%I|5
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criteria.setFirstResult(startIndex).setMaxResults UGxF}Q
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(pageSize).list(); IL,iu
PaginationSupport ps = 33ZHrZ
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new PaginationSupport(items, totalCount, pageSize, G?^w
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startIndex); \j<aFOT(
return ps; : sG/
} l1.eAs5U
}, true); 29nMm>P.e
} Mr*CJgy
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public List findAllByCriteria(final dUBf.2ry
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DetachedCriteria detachedCriteria){ _aU
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return(List) getHibernateTemplate hltUf5m'b
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().execute(new HibernateCallback(){ J vl-=~
publicObject doInHibernate }R~C<3u\2
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(Session session)throws HibernateException { RT2&^9-
Criteria criteria = -
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detachedCriteria.getExecutableCriteria(session); j*FpQiBoT
return criteria.list(); i!G<sfL
} hXD`OlX
}, true); xouBBb=
} b)>l7nOc
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public int getCountByCriteria(final QO>)ug+
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DetachedCriteria detachedCriteria){ S"fqE%
Integer count = (Integer) np\*r|U
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getHibernateTemplate().execute(new HibernateCallback(){ Pz|}[Cx-
publicObject doInHibernate wH\
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(Session session)throws HibernateException { &?I3xzvK
Criteria criteria = BwYR"
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detachedCriteria.getExecutableCriteria(session); bo??91B^7
return "HLh3L~
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criteria.setProjection(Projections.rowCount Va4AE)[/*
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()).uniqueResult(); _QtW)\)5\
} o9v.]tb
}, true); wuhL r(
return count.intValue(); {)4@rM
} +3pfBE|
} MnQ 6 !1Z
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用户在web层构造查询条件detachedCriteria,和可选的 AY]rQ:I
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;`Sn66&
;
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PaginationSupport的实例ps。 :FixLr!q
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ps.getItems()得到已分页好的结果集 :io~{a#.2\
ps.getIndexes()得到分页索引的数组 "VeNc,-nfQ
ps.getTotalCount()得到总结果数 B~3qEdoK5`
ps.getStartIndex()当前分页索引 aSeh?2n8
ps.getNextIndex()下一页索引 HmV JkkksJ
ps.getPreviousIndex()上一页索引 #b1/2=PA
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c ;'7o=rr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 !/"y
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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 8WwLKZ}
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一下代码重构了。 3H5<w4yk
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我把原本我的做法也提供出来供大家讨论吧: i,/Q.XL
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首先,为了实现分页查询,我封装了一个Page类: aVn+@g<.
java代码: {z# W-
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/*Created on 2005-4-14*/ V/8yW3]Xy
package org.flyware.util.page; <h~_7Dn
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/** C2?p>S/q
* @author Joa h-@_.&P0e
* a{iG0T.{Yh
*/ c+u) C%g
publicclass Page { e pAC%a
2J7JEv|
/** imply if the page has previous page */ Z15b'^)?9
privateboolean hasPrePage; 4hV~
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/** imply if the page has next page */ KkZ o|\V
privateboolean hasNextPage; .7H*F9
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/** the number of every page */ ="[6Z$R
privateint everyPage; m6
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Va\?"dH>M
/** the total page number */ B=2f-o
privateint totalPage; +'D
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"\kr;X'
/** the number of current page */ D?cE$P
privateint currentPage; n4EZy<~m
zj'uKBDl
/** the begin index of the records by the current ;Z#DB$o\
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query */ :;Wh!8+j
privateint beginIndex; G6j9,#2@
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/** The default constructor */ FuO'%3;c
public Page(){ gx6$:j;
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} f@J-6uQ7w
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j:
/** construct the page by everyPage M{~KT3c
* @param everyPage a.g:yWL\
* */ -\fn \n
public Page(int everyPage){ }MV=t7x9+
this.everyPage = everyPage; AY%Y,<a
} Og<UW^VR
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/** The whole constructor */ ^1+&)6s7V
public Page(boolean hasPrePage, boolean hasNextPage, \YsYOFc|
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8Vqh1<
int everyPage, int totalPage, (B;rjpK
int currentPage, int beginIndex){ V|bN<BYJ
this.hasPrePage = hasPrePage; SN|:{Am
this.hasNextPage = hasNextPage; v"smmQZik
this.everyPage = everyPage; /bv4/P
this.totalPage = totalPage; {AqPQeNgz
this.currentPage = currentPage; "4qv
yVOE
this.beginIndex = beginIndex; 6}e"$Ee}9
} S%m$LM]NCg
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/** ~@bh[o~rF
* @return Zae$M0)
* Returns the beginIndex. HWT^u$a"
*/ XqTDLM&
publicint getBeginIndex(){ |0/~7l
return beginIndex; ~!W{C_*N
} _8"%nV
qU,u(El
/** RgT|^|ZA
* @param beginIndex )]5}d$83
* The beginIndex to set. }W k!):=y
*/ QWV12t$v
publicvoid setBeginIndex(int beginIndex){ B>M @ '
this.beginIndex = beginIndex; Q{+&3KXH
} }Qm: g
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/** R7d45Wl
* @return ,L}
* Returns the currentPage. pe$l'ur
*/ |\MgE.N
publicint getCurrentPage(){ mdTCe
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return currentPage; vMV}M%~
} 2bk~6Osp
pT` oC&
/** O
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* @param currentPage UMbM3m=\
* The currentPage to set. L) ]|\|
*/ 8/dx)*JCq
publicvoid setCurrentPage(int currentPage){ u:f.g?!`"
this.currentPage = currentPage; 7U\GX
} G>);8T%l
nuip
/** zn'F9rWx>
* @return F"<TV&xf
* Returns the everyPage. &{c.JDO
*/ hf~'EdU
publicint getEveryPage(){ G F-\WD
return everyPage; P[E5e+A)
} 8=U0\<wT
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/** C.[abpc
* @param everyPage z.q^`01/H
* The everyPage to set. 5dE@ePO[/9
*/ M &g1'zv?/
publicvoid setEveryPage(int everyPage){ 3b2[i,m<L
this.everyPage = everyPage; lef,-{X-
} EBX+fzjQo
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/** hY@rt,! 8
* @return Io81zA
* Returns the hasNextPage. M_wj>NXZ
*/ #DI%l`B
publicboolean getHasNextPage(){ j r<`@
return hasNextPage; <!s+X_^
} :d
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/** +I {ZW}rA
* @param hasNextPage `"/s," c:D
* The hasNextPage to set. *+ql{\am4N
*/ ?B"k9+%5ej
publicvoid setHasNextPage(boolean hasNextPage){ ""JTU6]MS
this.hasNextPage = hasNextPage; R>iRnrn:-
} tJ
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/** [%alnY
* @return '51 8S"T @
* Returns the hasPrePage. axSJ:j8
*/ M[^
publicboolean getHasPrePage(){ ueyz@{On~
return hasPrePage; +;P8QZK6
} 75+#)hNa!P
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/** ]b"Oy}ARW
* @param hasPrePage em+dQ15
* The hasPrePage to set. bV5 {
*/ "+g9}g
publicvoid setHasPrePage(boolean hasPrePage){ H<|ilL'fX
this.hasPrePage = hasPrePage; .S l{m[nV8
} `5V=U9zdE
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/** 8T7E.guYr
* @return Returns the totalPage. wE.CZ%f
* _R,VNk
*/ 6fozc2h@x%
publicint getTotalPage(){ }Ss]/_t
return totalPage; ;wi}6rF%[i
} zq=X;}qYj
a5/6DK>
/** b1(7<o
* @param totalPage 3 %ppvvQ
* The totalPage to set. J3F-Yl|
*/ i|]Kw9
publicvoid setTotalPage(int totalPage){ !\
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this.totalPage = totalPage; QUPZe~G>L
} Nq`@ >Ml
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} (h}5*u%h
Q M#1XbT
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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 b) k\?'j
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个PageUtil,负责对Page对象进行构造: NtuO&{}i
java代码: dr|>P*
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/*Created on 2005-4-14*/ 3D"2yTM(
package org.flyware.util.page; RObo4
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import org.apache.commons.logging.Log; 1G0U}-6RH
import org.apache.commons.logging.LogFactory; n9
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/** iP7
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* @author Joa 5s=ZA*(sY
* CFm(
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*/ q&/<~RC*
publicclass PageUtil { q#{.8H-X'
vD=>AAvG
privatestaticfinal Log logger = LogFactory.getLog mv5=>Xc6
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(PageUtil.class); ! :[`>=!
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/** 3pxZk%
* Use the origin page to create a new page q c(R
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* @param page C 2f=9n/
* @param totalRecords qO;.{f
* @return aC\O'KcH
*/ MI:
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publicstatic Page createPage(Page page, int -/x=`S*
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totalRecords){ n~1F[ *
return createPage(page.getEveryPage(), RcZg/{[{
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page.getCurrentPage(), totalRecords); scf.>K2
} kLsp0%2
WH>= *\
/** )\S3Q
* the basic page utils not including exception o!]muO*Rm
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handler 5r&bk`
* @param everyPage }Y}f73-|
* @param currentPage }McqoZ%F
* @param totalRecords PykVXZ7j;
* @return page ;6 ?a8t@
*/ @q98ac*{
publicstatic Page createPage(int everyPage, int 9nM_LV
/|<Pn!}J
currentPage, int totalRecords){ ,Wv@D"4?
everyPage = getEveryPage(everyPage); |/qwR~
currentPage = getCurrentPage(currentPage); Y X`BX$
int beginIndex = getBeginIndex(everyPage, ^(j}'p,
)8cb @N
currentPage); K nl`[Nl
int totalPage = getTotalPage(everyPage, T*Dd%
f
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totalRecords); HT`k-}ho,
boolean hasNextPage = hasNextPage(currentPage, N)I9NM[
6'{/Ote
totalPage); D*%? 0
boolean hasPrePage = hasPrePage(currentPage); Q9yIQ{>H[
IP LKOT~
returnnew Page(hasPrePage, hasNextPage, syJLcK+e
everyPage, totalPage, ?*)Q[P5
currentPage, e(=() :4is
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beginIndex); b<\2j5
} ME0vXi
]9
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privatestaticint getEveryPage(int everyPage){ R)@2={fd}
return everyPage == 0 ? 10 : everyPage; GM~Ek]9C%
} z#[PTqD-_
L@5j? N?F
privatestaticint getCurrentPage(int currentPage){ t)4><22of
return currentPage == 0 ? 1 : currentPage; OH\(;RN*
} DruiiA
kF;N}O2?{
privatestaticint getBeginIndex(int everyPage, int JdM0f!3
rAn:hR{
currentPage){ 7C&J88|\
return(currentPage - 1) * everyPage; o7r7HmA@
} %`_Rl>@K=
pjN4)y>0
privatestaticint getTotalPage(int everyPage, int }T5
E^
1dhuLN%Ce
totalRecords){ e=cb%
int totalPage = 0; h-f`as"d
`f[
if(totalRecords % everyPage == 0) EED0U?
totalPage = totalRecords / everyPage; =*5< w
else `SH14A*
totalPage = totalRecords / everyPage + 1 ; y}F;~H~P
Ke;eI+P[
return totalPage; @!Z1*a.
} w+wg)$i
8nu@6 )#
privatestaticboolean hasPrePage(int currentPage){ \{a!Z&df
return currentPage == 1 ? false : true; 6!`GUU
} n)Z u>
YMU2^,3
privatestaticboolean hasNextPage(int currentPage, Q}: $F{
{>3J 96
int totalPage){ :cxA
return currentPage == totalPage || totalPage == EY`]""~8v
$ {h1(ec8
0 ? false : true; q^DQ9B
} ]#\De73K
:5X^t
*x &
} 'ln
o#
z:ZXdB)L)
r j.X"
k\TP3*fD
j "s7P%
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。 j8G$ , ~v
lu?:1V-
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 GBl[s,g[|
*EwDwS$$
做法如下: dBkM~"
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a&Z,~Vp
]6
HR
的信息,和一个结果集List: fm^J-
java代码: B'e@RhU;
9sN#l
;:,U]@
/*Created on 2005-6-13*/ S,s#D9NU
package com.adt.bo; M2$Hb_S{
y9N6!M|'y
import java.util.List; [}=a6Q>)
^;9<7h[l
import org.flyware.util.page.Page; %L|xmx!c
6)PnzeYW
/** vqAEF^HYry
* @author Joa ;X
N Ahg7
*/ v5 @9
publicclass Result { BM{*5Lf
>m:n6M'r
private Page page; ~>H,~</`
i-ww@ XOQ
private List content; (HXKa][T
.Y0O.
/** gq]@*C
* The default constructor
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*/ !|l7b2NEz-
public Result(){ ^`[<%.
super(); XtQwLH+F
} "D'rsEh
~.4y* &
/** &lgzNC9g%
* The constructor using fields :-WNw
n
* 2q(gWhcj
* @param page 44s 9\
* @param content 8`wKq6
*/ WD_{bd)
public Result(Page page, List content){ yEos$/*u-N
this.page = page; VJP #
this.content = content; JeN]sK)8x
} %
H<@Y$r
A0Q`Aqs
/** tLU@&NY`
* @return Returns the content. @^<&LG5^
*/ '"+Gn52#
publicList getContent(){ %JH/|mA&|
return content; _#1EbvO*l
} 5NC77}^.
PJ4/E
/** l =t/"M=
* @return Returns the page. ,zuS)?
*/ 7n o6
public Page getPage(){ $e2+O\.>
return page; d!46`b$rd
} I o"3wL)2
d>NO}MR
/** d&AO4^
* @param content ^<Gxip
* The content to set. XdmpfUR,13
*/ P*B@it
public void setContent(List content){ 2
6DX4
this.content = content; Hj(K*z
} =)G]\W)m
6.a5%:
/** 6"+9$nFyW
* @param page ?A3u2-
* The page to set. o>nw~_ H\
*/ a6gPJF[Jo
publicvoid setPage(Page page){ m+(g.mvK>
this.page = page; vQp'bRR
} Zoc4@%
n
} 4x&Dz0[[S
<;yS&8
)-ojm$
NMfHrYHbh
/qJC p![X
2. 编写业务逻辑接口,并实现它(UserManager, oc]:Ty
ul~6zBKO
UserManagerImpl) =|``d-
java代码: d=meh4Y
%[5GG d5w
ke!
/*Created on 2005-7-15*/ S~ Z<-@S
package com.adt.service; )/vom6y*
!h4A7KBYG
import net.sf.hibernate.HibernateException; hJ]Oa7r
|/H?\]7
import org.flyware.util.page.Page; maDWV&Db
/V{UTMSz
import com.adt.bo.Result; QuG"]$
/g.c(-#]
/** :.-z!
* @author Joa vK@UK"m
*/ NiWAJ]Z
publicinterface UserManager { i}zz!dJTE
Tg"? TZO~
public Result listUser(Page page)throws @MVul_@6
N&p0Emg
HibernateException; (&Jo.
<
(CRx'R
} Bm,Vu 1]t
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'tw
]jMD
wggB^ }~
6pSTw\/6
java代码: 49M1^nMvoo
nIr`T^c9c
j`"!G*Vh
/*Created on 2005-7-15*/ ,mHUo4h1O
package com.adt.service.impl; 8C8S)
;
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import java.util.List; A.("jb@I
,b&hLht
import net.sf.hibernate.HibernateException; .#bf9JOE
w&p(/y
import org.flyware.util.page.Page; 7 s{vou
import org.flyware.util.page.PageUtil; UO&$1rV
>V?0#f45@
import com.adt.bo.Result; h'};spv
import com.adt.dao.UserDAO; B~ i
import com.adt.exception.ObjectNotFoundException; ]vB\yQE
import com.adt.service.UserManager; D-LOjMe
I=#`8deH(
/** z`t~N
* @author Joa NJ.oM E@=
*/ ,8Po
_[
publicclass UserManagerImpl implements UserManager { .l_Nf9=
p*,T~(A6
private UserDAO userDAO; ssx#|InY
B7[d^Y60B
/** &nXE?-J
* @param userDAO The userDAO to set. ObEz 0Rj
*/ z2t+1In,
publicvoid setUserDAO(UserDAO userDAO){ hXth\e\[{`
this.userDAO = userDAO; jzJTV4&zjs
} mN}szW,
{eI'0==
/* (non-Javadoc) t4#gW$+^?H
* @see com.adt.service.UserManager#listUser r!dWI
.!KsF
h,pK
(org.flyware.util.page.Page) {Ba&
*/ vs=q<Uw)
public Result listUser(Page page)throws "lw|EpQk`
|&JeJ0k>~
HibernateException, ObjectNotFoundException { }}$@Tij19[
int totalRecords = userDAO.getUserCount(); Znb7OF^#"
if(totalRecords == 0) jhf3(hx&F
throw new ObjectNotFoundException p>+9pxx~U
xmcZN3 ){+
("userNotExist"); vio>P-2Eho
page = PageUtil.createPage(page, totalRecords); f\dfKNm6
List users = userDAO.getUserByPage(page); v.Q#<@B^:
returnnew Result(page, users); v;e8W9M
} Jg[Ao#,==
=/46;844T
} vuPNru" 2
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Ch>F11kC
wxo
2=NaqHt(
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 )
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m
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询,接下来编写UserDAO的代码: aim\3y~
3. UserDAO 和 UserDAOImpl: 8]&:'
java代码: T8z?_ *k
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WM
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/*Created on 2005-7-15*/ Pn OWQ8=
package com.adt.dao; `L`+`B
{owuYVm
import java.util.List; K-C,n~-
WV$CZgL
import org.flyware.util.page.Page; {IV%_y?
i>YQ<A1
import net.sf.hibernate.HibernateException; K#wA ;
1B2#uhT]r
/** ]qv0Y~+`-K
* @author Joa Yu3S3aRE
*/ 4G(7V:
publicinterface UserDAO extends BaseDAO { K'r;#I|"J
l(sVnhL6h
publicList getUserByName(String name)throws !="q"X/*
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HibernateException; YkWHI(p
h7"U1'b
publicint getUserCount()throws HibernateException; $q@d.Z>;
7amVnR1f
publicList getUserByPage(Page page)throws |cma7q}p
OY`B{jV-
HibernateException; KN|<yF
}<A.zwB<i
} EYq?NL='
[UzD3VPg
~#*C,4m
8O,\8:I#
Yao}Xo9}
java代码: f?sm~PwC-
o2ggHZe/=@
Bxm,?=h
/*Created on 2005-7-15*/ WMa0L&C~v
package com.adt.dao.impl; MMFwT(l<1
N2}SR|.
import java.util.List; H/O.h@E4X
Kk8}m;
import org.flyware.util.page.Page; ~U&NY7.@
AYA{_^#+3
import net.sf.hibernate.HibernateException; ,D+ydr
import net.sf.hibernate.Query; [#Y
L_*p
H>EM3cFU
import com.adt.dao.UserDAO; TBBnsj6e
SU ~a()"
/** SO0\d0?u
* @author Joa $~G,T
g
*/ (E0
public class UserDAOImpl extends BaseDAOHibernateImpl .r<aPy$
h4pS~/
implements UserDAO { {]R'U/
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/* (non-Javadoc) NZq-%bE
* @see com.adt.dao.UserDAO#getUserByName ccuGM W G*
.c"nDCFVR
(java.lang.String) ^}=)jLS
*/ y d97ys
publicList getUserByName(String name)throws `-L?x2)U
dM-cQo:
HibernateException { 1(?4*v@B
String querySentence = "FROM user in class .zO2g8(VR
c1'@_Is
com.adt.po.User WHERE user.name=:name"; X,|8Wpi=
Query query = getSession().createQuery FXof9fa_B
YJ _eE
(querySentence); C$y6^/7)
query.setParameter("name", name); YvU%OO-+,
return query.list(); cJ96{+
} p`Pa;=L
~$HB}/
/* (non-Javadoc) Y_'ERqQ
* @see com.adt.dao.UserDAO#getUserCount() n N<N~
*/ t/iI!}
publicint getUserCount()throws HibernateException { b&z#ZY
int count = 0; lYx_8x2
String querySentence = "SELECT count(*) FROM Zo3!Hs ZA
;l@94)@0
user in class com.adt.po.User"; uks75W!}U
Query query = getSession().createQuery h:%,>I%{
d/7fJ8y8
(querySentence); MgJ6{xzz
count = ((Integer)query.iterate().next 7=l~fKu
\]tBwa
()).intValue(); @k?vbq
return count; QHk\Z
} }e[ E
?,vLRq.
/* (non-Javadoc) JmI%7bH@
* @see com.adt.dao.UserDAO#getUserByPage 7Q .Su
\zO.#H
(org.flyware.util.page.Page) r<`:Q]
*/ d9f7 &
publicList getUserByPage(Page page)throws +K4XMf
G$<(>"Yr~$
HibernateException { 5p0~AN)
String querySentence = "FROM user in class )0"Q
h
d6luksO*9
com.adt.po.User"; <|Td0|x
_q
Query query = getSession().createQuery cI=6zMB
>;fVuy
(querySentence); 5PeS/%uT@
query.setFirstResult(page.getBeginIndex()) @?,x3\N-
.setMaxResults(page.getEveryPage()); 8 1,N92T5
return query.list(); ZoG@"vr2
} > G\0Z[<v,
gQ+]N*.
} \`n(JV
l;; 2\mL?
Y6jyU1>
6j%%CWU{~
U4 !bW
至此,一个完整的分页程序完成。前台的只需要调用 #"gt&t9Q
8Y`Lq$u
userManager.listUser(page)即可得到一个Page对象和结果集对象 2.q Zs8&
hY"eGaoF"
的综合体,而传入的参数page对象则可以由前台传入,如果用 6V;Dcfvi
_Id'56N]J!
webwork,甚至可以直接在配置文件中指定。 dN{At-
y~9wxK
下面给出一个webwork调用示例: O<m46mwM
java代码: @kYY1m v;
_jQ:9,;
A
iM]O
/*Created on 2005-6-17*/ q7B5#kb
package com.adt.action.user; "Lp.*o
W5R/Ub@g
import java.util.List; m}]{Y'i]R
&;BhL%)}
import org.apache.commons.logging.Log; QiPqN$n
import org.apache.commons.logging.LogFactory; _}l(i1o,/
import org.flyware.util.page.Page; |+cz\+
t~+M>Fjm?d
import com.adt.bo.Result; <y6`8J7:
import com.adt.service.UserService; PQHztS"
import com.opensymphony.xwork.Action; -)V0D,r$[
*6s_7{;
/** {*_Ln
* @author Joa Aiq Kf=
*/ LO`0^r
publicclass ListUser implementsAction{ 46?z*~*G
W{,fpm
privatestaticfinal Log logger = LogFactory.getLog Hv/C40uM-
eR!#1ar
(ListUser.class); x ytrd.
A4j,]hOD
private UserService userService; odP<S.
o@Ye_aM~?Y
private Page page; 1[egCC\Mo_
dwA"QVp{
privateList users; ,ri&zbB
RD`|Z~:q:K
/* )vtbA=RH?
* (non-Javadoc) i~!g9o(
* yFE0a"0y
* @see com.opensymphony.xwork.Action#execute() N8sT?
*/ [L%Ltmx
publicString execute()throwsException{ xQ9t1b|{e
Result result = userService.listUser(page); q!z?Tn#!jd
page = result.getPage(); s< tG
users = result.getContent(); 1g;2e##)
return SUCCESS; Kw fd
S(
} <J8c dB!e
?eJ' $
/** *bK=<{d1P
* @return Returns the page. Y>$5j}K
*/ e~vO
public Page getPage(){ <&eJIz=
return page; X@~/.H5
} pSx5ume95"
lxn/97rA
/** 49FP&NgK
* @return Returns the users. \`k=9{R.
*/ qnP4wRpr
publicList getUsers(){ MWwqon|
return users; X}#vt?mu
} G4
7^xR
w,1N ;R&
/** HNkOPz+d&8
* @param page r/h\>s+N
* The page to set. }s2CND
*/ :(q4y-o6
publicvoid setPage(Page page){ W6?=9].gc
this.page = page; |gkNhxzB
} <:-4GJH=
7FwtBO
/** C:1(<1K
* @param users 'DW|a
* The users to set. aZf/WiR2
*/ (j>`+F5f
publicvoid setUsers(List users){ ET[5`z
this.users = users; SU%O \4Ty
} .{gDw
m{>1#1;$t
/** Z|K HF"
* @param userService \Fjasz5E'
* The userService to set. GW
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*/ CC^D4]ug
publicvoid setUserService(UserService userService){ _J C*4
this.userService = userService;
s(_z1
} ?g1eW q&
} t__f=QB/
8jCho
9DBX.|
hw"2'{"II
%:C6\4
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, wPI!i K@Ro
Xau%v5r
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 #>yOp *
1
F:bExQ
么只需要: wQW`Er3w
java代码: Jk{SlH3'
{X?Aj >l
Z +/3rd
<?xml version="1.0"?> 5CnNp?.t^
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork l&\y]ZV={
LcLHX
1.0//EN" "http://www.opensymphony.com/xwork/xwork- a[;L+
Ft;x@!h%
1.0.dtd"> XK~HfA?
)4fQ~)
<xwork> ~_BjcY
koB'Zp/FaY
<package name="user" extends="webwork- 5[g&0
7OLHY t9
interceptors"> b\^DQZmth
O<fy^[r:`
<!-- The default interceptor stack name $,Q]GIC
&y0Gdzf