Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 V7+fNr]I
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )=~OP>7B
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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 oGtz*AP%
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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 =tk O^
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分页支持类: VLdQXNg9W"
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java代码: @%aU)YDwi
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package com.javaeye.common.util; WQJnWe
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import java.util.List; zwLJ|>
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publicclass PaginationSupport { {*BZ;Xh\8
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publicfinalstaticint PAGESIZE = 30; d~0k}|>
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privateint pageSize = PAGESIZE; n'5LY9"
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privateList items; MWl2;qi
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privateint totalCount; yhuzjn
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privateint[] indexes = newint[0]; 3J3Yt`
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privateint startIndex = 0; (XU(e
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public PaginationSupport(List items, int nT:F{2 M;
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totalCount){ ]jB`"to*}
setPageSize(PAGESIZE); -4;$NiB?
setTotalCount(totalCount); X21k7 Ls
setItems(items); 6?BV J
setStartIndex(0); Ue?mb$ykC.
} -$A
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public PaginationSupport(List items, int kgv29j?k;
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totalCount, int startIndex){ jap5FG+2
setPageSize(PAGESIZE); <Od5}
setTotalCount(totalCount); /a .XWfu
setItems(items); W6A-/;S\
setStartIndex(startIndex); -T8'|"g
} [.Y]f.D
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public PaginationSupport(List items, int 6N#0D2~^
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totalCount, int pageSize, int startIndex){ INRP@Cp1
setPageSize(pageSize); c!ul9Cw
setTotalCount(totalCount); _, r6t
setItems(items); ev[!:*6P
setStartIndex(startIndex); Jwtt&" c0.
} .5E6MF
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publicList getItems(){ wZs jbNf`K
return items; uE ^uP@d
} Yma-$ytp
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publicvoid setItems(List items){ ~5;2 ni8n
this.items = items; (
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} AT-
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publicint getPageSize(){ er0y~
return pageSize; %%{f-\-7Ig
} ,R7RXpP7t
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publicvoid setPageSize(int pageSize){ ]A,Og_g
this.pageSize = pageSize; 8=,?Bh".
} x4CSUcKb
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publicint getTotalCount(){ QD;:!$Du
return totalCount; C5^9D
} _X~xfmU
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publicvoid setTotalCount(int totalCount){ n%d7`?tm4
if(totalCount > 0){
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this.totalCount = totalCount; 4vMjVbr
int count = totalCount / J l
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pageSize; V`_)H
if(totalCount % pageSize > 0) 2Xqa?ay0>
count++; |o#pd\
indexes = newint[count]; m/"}Y]n!
for(int i = 0; i < count; i++){ o(@^V!}V
indexes = pageSize * _m#P\f'p
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} p&lT! 5P!A
}else{ N 8pzs"
this.totalCount = 0; \os"j
} @ 5V3I^
} e[g.&*!
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publicint[] getIndexes(){ |Li9Y"5
return indexes; {KqERS&
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} <xwaFZ
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publicvoid setIndexes(int[] indexes){ BUU ) Sz
this.indexes = indexes; WjF#YW\
} 0:zDt~Ju
x-HR [{C
publicint getStartIndex(){ uE&2M>2
return startIndex; )'e9(4[V1
} s%@HchZ 1
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publicvoid setStartIndex(int startIndex){ VR vX^w0
if(totalCount <= 0) 'ExTnv ~
this.startIndex = 0; P+(Ys[J3
elseif(startIndex >= totalCount) l/6(V:
this.startIndex = indexes zF_aJ+i:~
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[indexes.length - 1]; M6*8}\
elseif(startIndex < 0) >5bd!b,
this.startIndex = 0; skBzwVW I
else{ b-)3MR:4
this.startIndex = indexes j?s+#t
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[startIndex / pageSize]; ez^b{s`
} !K/zFYl
} w\Bx=a>vc
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publicint getNextIndex(){ Tz 2<# pLR
int nextIndex = getStartIndex() + XCku[?Ix
F ][QH\N
pageSize; 7Jvb6V<R
if(nextIndex >= totalCount) H2D j`0
return getStartIndex(); "T'?Ah6
else x $=-lB
return nextIndex; h?2 :'Vu]
} AHtLkfr(r
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publicint getPreviousIndex(){ } l4d/I
int previousIndex = getStartIndex() - qra5&Fvb
Q.]RYv}\
pageSize; *Zi:^<hv
if(previousIndex < 0) mtu`m6Xix
return0; UkV{4*E
else fxL0"Ry
return previousIndex; =a3qpPkx
} < &~KYu\r
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} 1%,AU
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抽象业务类 WQT;k0;T]
java代码: d)7V:
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/** auP6\kpMe
* Created on 2005-7-12 1Ev#[FOc
*/ iSz?V$}?
package com.javaeye.common.business; I%<,JRAV
Q #%C)7)
import java.io.Serializable; dJ0qg_ U&
import java.util.List; t6H9Q>*
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import org.hibernate.Criteria; |p1pa4%}
import org.hibernate.HibernateException; [rt+KA
import org.hibernate.Session; D3+UV+&R/
import org.hibernate.criterion.DetachedCriteria; $2j?Z.yEG
import org.hibernate.criterion.Projections; .g6DKjy>
import e~,/Z\i
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org.springframework.orm.hibernate3.HibernateCallback; {} 11U0
import =_/,C
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org.springframework.orm.hibernate3.support.HibernateDaoS pWwB<F
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upport; 4l~0LdYXKm
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import com.javaeye.common.util.PaginationSupport; m8|&z{
.RNr^*AQ
public abstract class AbstractManager extends Z=vzF0
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HibernateDaoSupport { NI^[7.2
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privateboolean cacheQueries = false; P|S'MS';:
!1H\*VM"
privateString queryCacheRegion;
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publicvoid setCacheQueries(boolean sH>Z{xjr
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cacheQueries){ Q\DD^Pbq
this.cacheQueries = cacheQueries; o9:GKc
} :z EhPx;B7
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publicvoid setQueryCacheRegion(String z5CWgN
dpBG)Xzoyv
queryCacheRegion){ %`c?cB
this.queryCacheRegion = S|8O$9{x9q
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queryCacheRegion; (\si/&
} 6c3+q+#J2
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publicvoid save(finalObject entity){ =%:mZ@x'
getHibernateTemplate().save(entity); oy-Qy
} *n)3y.s
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publicvoid persist(finalObject entity){ 2
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getHibernateTemplate().save(entity); a#=GLB_P(
} $cev,OW6]
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publicvoid update(finalObject entity){ ~BVg#_P
getHibernateTemplate().update(entity); |52VHW8c
} %S22[;v{N
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publicvoid delete(finalObject entity){ '3wte9E/
getHibernateTemplate().delete(entity); ,\5]n&T;r
} @ :i>q$aF
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publicObject load(finalClass entity, voaRh@DZ%/
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finalSerializable id){ t=~5I>
return getHibernateTemplate().load kTG}>I
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(entity, id); muQ7sJ9
r
} LiJ;A*
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publicObject get(finalClass entity, .N]^g#
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finalSerializable id){ bTKzwNx
return getHibernateTemplate().get Tk/K7h^
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(entity, id); |mrAvm}
} c*!bT$]~\
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publicList findAll(finalClass entity){ BZsw(l4/0'
return getHibernateTemplate().find("from b/]C,P
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" + entity.getName()); 8Md*9E#J("
} sl%B-;@I
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publicList findByNamedQuery(finalString O>w$
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namedQuery){ QsI>_<r
return getHibernateTemplate oHu0] XA
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().findByNamedQuery(namedQuery); k`.-PU
} \I#2Mq?
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publicList findByNamedQuery(finalString query, nb22bXt
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finalObject parameter){ J_U1eSz<j
return getHibernateTemplate a+zE`uY
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().findByNamedQuery(query, parameter); EEn}Gw
} L ! yl^c
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publicList findByNamedQuery(finalString query, VILzx+v
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finalObject[] parameters){ r6 ,5&`&
return getHibernateTemplate 2={`g/WeE
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().findByNamedQuery(query, parameters); <J {VTk ~
} C/_W>H_
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publicList find(finalString query){ +n^$4f
return getHibernateTemplate().find .0.Ha}{6b
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(query); 0l^-[jK)
} WK/Byd.Z
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publicList find(finalString query, finalObject E;D9S
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parameter){ v~ZdMQvwt
return getHibernateTemplate().find 5cgDHs
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(query, parameter); *8,]fBUq
} h+CTi6-p
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public PaginationSupport findPageByCriteria 0z_e3H{P27
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(final DetachedCriteria detachedCriteria){ #r#UO
return findPageByCriteria (6>8Dt 9[
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); EF qWnz
} : )cPc7$8
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public PaginationSupport findPageByCriteria K\5@yqy5
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(final DetachedCriteria detachedCriteria, finalint #l+U(zH:JG
*Jmy:C<>
startIndex){ GO+cCNMa"
return findPageByCriteria
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x =5k74
(detachedCriteria, PaginationSupport.PAGESIZE, o[O-|XL_
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startIndex); Q(T)s
} 75jq+O_:
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public PaginationSupport findPageByCriteria GTeFDm;T^
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(final DetachedCriteria detachedCriteria, finalint JC_Y#kN@z
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pageSize, U_wn/wcLS
finalint startIndex){ m@u!frE,
return(PaginationSupport) &Op, ?\
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getHibernateTemplate().execute(new HibernateCallback(){ /![S 3Ol
publicObject doInHibernate %kxq" =3
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(Session session)throws HibernateException { e>#*$4tg
Criteria criteria = 7*r
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detachedCriteria.getExecutableCriteria(session); `kpX}cKK}
int totalCount = \A6MVMF8
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((Integer) criteria.setProjection(Projections.rowCount %FDi7Rx
-}/u?3^-
()).uniqueResult()).intValue(); >8"oO[U5>
criteria.setProjection w-C~
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(null); (CJiCtAsl`
List items = `TYQ^Zm
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criteria.setFirstResult(startIndex).setMaxResults ms{:=L2$$
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(pageSize).list(); &=Gz[1
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PaginationSupport ps = y<W?hE[
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new PaginationSupport(items, totalCount, pageSize, J;W(}"cFq
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startIndex); %0fF_OU
return ps; u_;*Ay
} Nwr.mtvh
}, true); /;-KWu+5=
} 6vbWe@#U/
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public List findAllByCriteria(final CoDu|M%
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DetachedCriteria detachedCriteria){ ZF"f.aV8)
return(List) getHibernateTemplate !rZO~a0
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().execute(new HibernateCallback(){ guz{DBlK
publicObject doInHibernate h!5^d!2,
gh=s#DQsFw
(Session session)throws HibernateException {
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Criteria criteria = 7}OzTup
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detachedCriteria.getExecutableCriteria(session); I+Qv $#S/
return criteria.list(); 2.ud P
} 9!b,!#=
}, true); f{xR
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} )8kcOBG^L
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public int getCountByCriteria(final )f-u x5
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DetachedCriteria detachedCriteria){ mr6/d1af_
Integer count = (Integer) !8yw!hA
et(/`
getHibernateTemplate().execute(new HibernateCallback(){ iDt^4=`
publicObject doInHibernate .281;] =
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(Session session)throws HibernateException { ,B%M P<Rz1
Criteria criteria = ePdM9%
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detachedCriteria.getExecutableCriteria(session); -fw0bL%0
return `,i'vb`W#b
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criteria.setProjection(Projections.rowCount '\\dh
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()).uniqueResult(); AN7WMX
} [/hS5TG|7
}, true); K-IXAdx
return count.intValue(); rLs)*A!
} 4J0{$Xuu0
} }dw`[{cm
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用户在web层构造查询条件detachedCriteria,和可选的 Yq}7x1mm
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 K]' 84!l
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PaginationSupport的实例ps。 yaD<jc(O
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ps.getItems()得到已分页好的结果集 9;2PoW8
ps.getIndexes()得到分页索引的数组 Ou</{l/
ps.getTotalCount()得到总结果数 tW 53&q\=
ps.getStartIndex()当前分页索引 aSd$;t~
ps.getNextIndex()下一页索引 $r|R`n =
ps.getPreviousIndex()上一页索引 dl;~-'0
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Jfa=#`
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 C-d|;R}Ww
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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 $'e;ScH
r_p9YS@I
一下代码重构了。 :zfnp,Gv
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我把原本我的做法也提供出来供大家讨论吧: ;tTM3W-h
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首先,为了实现分页查询,我封装了一个Page类: L,!?'.*/]
java代码: ]\5@N7h
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/*Created on 2005-4-14*/ #%z--xuJL
package org.flyware.util.page; cnvxTI<
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/** 11}sRu/
* @author Joa 4NN-'Z>a
* 9+@"DuYc6
*/ W"Hjn/xSS
publicclass Page { LqIMU4Ex
!iUdej^tx
/** imply if the page has previous page */ /+4Dq4{t)
privateboolean hasPrePage; ^@l_K +T
~ z4T
/** imply if the page has next page */ 58zs%+F
privateboolean hasNextPage; AE!WYE
PbxuD*LQ.
/** the number of every page */ nP?=uGqCBq
privateint everyPage; ^(m`5]qr7J
:|`'\%zW-
/** the total page number */ q)gZo[]~
privateint totalPage; 2!>phE
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/** the number of current page */ Jpg_$~k
privateint currentPage; ;=: R|
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k-b
/** the begin index of the records by the current Z)'jn8?P
Na: M1Uhb
query */ ;d G.oUk=
privateint beginIndex; S<Q8kW:
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!d#
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/** The default constructor */ /eDah3%d
public Page(){ %_u*5,w
RyD2LAf)J
} WhE5u&`
OzBo*X/p
/** construct the page by everyPage ar+mj=m
* @param everyPage 9bgKu6-X
* */ [UNfft=K3P
public Page(int everyPage){ .Y'kDuUu
this.everyPage = everyPage; %r6LU<;1@
} i051qpj
Oz^+;P1
/** The whole constructor */ ]@l~z0^|[_
public Page(boolean hasPrePage, boolean hasNextPage, "A__z|sQ
dDW],d}B;
}@@1N3nnxV
int everyPage, int totalPage, y[qW>
int currentPage, int beginIndex){ 25ul,t_Du
this.hasPrePage = hasPrePage; X X{:$f+
this.hasNextPage = hasNextPage; pX6T7
this.everyPage = everyPage; L"zOa90ig
this.totalPage = totalPage; +<:p`%
this.currentPage = currentPage; *[
Wh9 ,H
this.beginIndex = beginIndex; r!Eo8C
} sC
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/** %'\D_W&
* @return aEXV^5;,pJ
* Returns the beginIndex. jR@-h"2*A
*/ g%j z,|
publicint getBeginIndex(){ 4TG|
return beginIndex; F
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} cWFvYF
b_V)]>v+
/** wgLS9.
* @param beginIndex RfN5X}&A
* The beginIndex to set. z-7F,$
*/ W7(OrA!
publicvoid setBeginIndex(int beginIndex){ Zu%_kpW
this.beginIndex = beginIndex; <py~(q
} xO1d^{~^^
V2,.@j#
/** H _3gVrP_
* @return D:n0dfPU
* Returns the currentPage. uO[4 WZ
*/ /unOZVr(
publicint getCurrentPage(){ BC@"WlD
return currentPage; _tjFb_}Q
} 7Fy^K;V"
i":-g"d
/** 3M1(an\nW
* @param currentPage !+>yCy$~_
* The currentPage to set. {B\.8)&8
*/ 5I&^n0h|&
publicvoid setCurrentPage(int currentPage){ "g=ux^+X\
this.currentPage = currentPage; /E]4N=T
} ;F5B)&/B
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/** ?erDP8
* @return +IS$Un
* Returns the everyPage. -3 W4
*/ x,7axx6
publicint getEveryPage(){ ?: meix
return everyPage; YRYrR|I
} B;K{Vo:C
'6 /uc:zv
/** AOWI`
* @param everyPage j zPC9
* The everyPage to set. ;<&s_C3
*/ 6]rrj
publicvoid setEveryPage(int everyPage){ LXXxwIBS
this.everyPage = everyPage; ^k)f oD
} yTDoS|B+)
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/** iww h,(
* @return oOUVU}H
* Returns the hasNextPage. %^5$=w
*/ #%{\59/w
publicboolean getHasNextPage(){ r?[mn^Bo 5
return hasNextPage; L>L4%?
} uj:w^t ][
n `n3[
/** /kJ*WA?J
* @param hasNextPage 4\$Ze0tv
* The hasNextPage to set. w}(xs)`num
*/ 6*LU+U=`
publicvoid setHasNextPage(boolean hasNextPage){ {T^'&W>8G8
this.hasNextPage = hasNextPage; _ssHRbE
} >`NM?KP s
PO}Q8Q3
/** %(kq Hxc
* @return t|y4kM
* Returns the hasPrePage. 8n73MF
*/ pGcc6q1
publicboolean getHasPrePage(){ 4kz8U
return hasPrePage; Xoik%T-
} TY#1Z )%
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/** siG?Sd_2
* @param hasPrePage B{K'"uC
* The hasPrePage to set. pUwX
cy<n
*/ ^y3\e
publicvoid setHasPrePage(boolean hasPrePage){ yf8UfB#a
this.hasPrePage = hasPrePage; XWvs~Xw@
} Ey n3Vv?v
^twv0>vEo
/** |knP
* @return Returns the totalPage. Mb9q<4
* d,[KcX
*/ y$&a(S]
publicint getTotalPage(){ +Va?wAnr
return totalPage; Ab"uN
} i&30n#
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/** XVLuhwi
* @param totalPage n=SZ8Rj7
* The totalPage to set. TZP{=v<
*/ Ly<;x^D
publicvoid setTotalPage(int totalPage){ 0!VLPA:
this.totalPage = totalPage; X @Bpjg
} u}rot+)%
v\k,,sI
} p%ZiTrA1&D
/j)VES
:^s7#4%6
LWL>hd
I>3]4mI*a
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 =5/;h+bk+3
aK&+p#4t
个PageUtil,负责对Page对象进行构造: t?
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java代码: 6uXW`/lvX
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/*Created on 2005-4-14*/ YKg[k:F
package org.flyware.util.page; ,SM- Z`'
JAb?u.,Ns_
import org.apache.commons.logging.Log; j'i42-Lt/p
import org.apache.commons.logging.LogFactory; cGc|n3(
A]+h<Y~}
/** yKB[HpU-
* @author Joa NslA/"*
* +.lWck
*/ :]^P^khK
publicclass PageUtil { BXo|CITso
W^ :/0WR
privatestaticfinal Log logger = LogFactory.getLog f>5RAg
$
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(PageUtil.class); rc$!$~|I3Z
,/:a77
/** euhZ4+
* Use the origin page to create a new page CdDd+h8
* @param page j?f <hQ
* @param totalRecords o1WidJ"
* @return E)JyKm.
*/ 0Ad~!Y+1
publicstatic Page createPage(Page page, int <gdgcvd
o$ce1LO?|N
totalRecords){ !NYM(6!(
return createPage(page.getEveryPage(), F!&pENQ
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page.getCurrentPage(), totalRecords); m_$I?F0
} ij(4)=
ZGpTw[5ql
/** (Q5@MfK`
* the basic page utils not including exception UB$`;'|i
UY-IHz;&O-
handler 2-V)>98
* @param everyPage I26gGp
* @param currentPage n<:d%&^n
* @param totalRecords [b.'3a++
* @return page a*':W%7
*/ As+;qNO
publicstatic Page createPage(int everyPage, int %Lp7@
pTALhj#,
currentPage, int totalRecords){ ^Y7 /Ow
everyPage = getEveryPage(everyPage); "P'&+dH8
currentPage = getCurrentPage(currentPage); 9*|3E"Vr
int beginIndex = getBeginIndex(everyPage, v]T(zL|
<.WM-Z
currentPage); Q*:h/Lhb&
int totalPage = getTotalPage(everyPage, \$'m^tVU
XalJo@%-
totalRecords); rj,K`HD
boolean hasNextPage = hasNextPage(currentPage, !(*a+ur&i
>HPvgR/#BY
totalPage); O<1vSav!K
boolean hasPrePage = hasPrePage(currentPage); X&(ERY,h
KR=d"t Qw
returnnew Page(hasPrePage, hasNextPage, 4Oy.,MDQP
everyPage, totalPage, )[^y
t0%
currentPage, ;tp]^iB#
b0YiQjS6>
beginIndex); 1BMB?I
} TF=k(@9J?
)@]6=*%
privatestaticint getEveryPage(int everyPage){ Kx- s0cw
return everyPage == 0 ? 10 : everyPage; %o@['9U[j
} fey*la Xq
ACigeK^C}E
privatestaticint getCurrentPage(int currentPage){ m_m8c8{Y
return currentPage == 0 ? 1 : currentPage; _ }E-~I>
} ]<kupaRQ
h
`\$sT!Z
privatestaticint getBeginIndex(int everyPage, int O3kg
o_Jn_3=
currentPage){ a)!![X?\
return(currentPage - 1) * everyPage; 5: daa
} fvcW'T}r
xF(
bS+(o
privatestaticint getTotalPage(int everyPage, int *jM_ wwG
qzA`d
5rX
totalRecords){ 8 ]q
int totalPage = 0; 1,"I=
~;M)qR?]W
if(totalRecords % everyPage == 0) rv9B}%e
totalPage = totalRecords / everyPage; yoBgr7gS
else _wf5%(~b
totalPage = totalRecords / everyPage + 1 ; "]VDY)
Y5dD|]F|
return totalPage; 0QMTIAW6h
} %#~((m1
60!1D>,
privatestaticboolean hasPrePage(int currentPage){ gNShOu
return currentPage == 1 ? false : true; )~ 0}Et l
} {5^K Xj$B
JD6aiI!Su
privatestaticboolean hasNextPage(int currentPage, XJqTmj3
]@v}y&
int totalPage){ CuH2E>wz
return currentPage == totalPage || totalPage == T~BA)![
qG<7hr@x]
0 ? false : true; TG}d3ZU
!
}
#j;Tb2&w
A)tP()+)
\(I0wEQo$
} &59F8JgJ
*G9sy_
bEm7QgV{X
-LtK8wl^
7kKuZW@K-
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 57wFf-P
v??TJ^1
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ,57$N&w
0}{'C5
做法如下: rQ/,XH
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 k1)%.pt%
E@-ta):
的信息,和一个结果集List: eG5Y+iL-V
java代码: rLU'*}
e,>%Z@92(
98RKCc9h
/*Created on 2005-6-13*/ B
z^|SkEit
package com.adt.bo; !Uh2}ic
A4.4Dji,x
import java.util.List; (D<(6?
Y34/+Fi
import org.flyware.util.page.Page; =<c#owe:m
F>zl9Vi<
/** -&|:0#@P
* @author Joa <A>)[u
*/ {ox2Tg?
publicclass Result { Qck|#tc
(hB?
private Page page; \8S~c8Z~
D-2.fjo9!
private List content; G,f-.
:`\)
P,
/** ?WUF!Jk
* The default constructor ]0c+/ \b&
*/ (@r
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public Result(){ X
T[zj<&_
super(); AH#4wPxF
} ]5Qy
<q
(z>*-e
/** JTU#vq:TY
* The constructor using fields FOwnxYGVf
* P`$!@T0=
* @param page WOLuw%
* @param content z'7[T ie
*/ M;w?[yEZ
public Result(Page page, List content){ KS}hU~
this.page = page; izgp*M,
this.content = content; ^T5X)Nu{=C
} Pq9|WV#F5/
2)X4y"l
/** G{Yz8]m
* @return Returns the content. fu[K".
*/ .IarkeCtb
publicList getContent(){ ^n1%OzGK#
return content; '1?\/,em
} dS2G}L^L
/E;y,o75
/** ^3VR-u <O
* @return Returns the page. );V2?G`/
*/ +Hvc_Av''
public Page getPage(){ ;-P)m
return page; dCyqvg6u
} <BFQ:
#Z+i~t{e(
/** 1CU>L[W)
* @param content qfY5Ww$8
* The content to set. r3E!dTDWq
*/ :W#rhuzC
public void setContent(List content){ b-ll
this.content = content; ?eH&'m}-
} vo>d!rVCV
~Q{QM: k
/** aj8A8ma*}
* @param page [x=jH>Y
* The page to set. z>sbr<doa
*/ \B F*m"lz
publicvoid setPage(Page page){ > fnh+M
this.page = page; dr)YzOvba
} =4V&*go*\
} =_$Qtq+h
-;f*VM.a
P-F)%T[
|4$M]M f0
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2. 编写业务逻辑接口,并实现它(UserManager, T134ZXqqz
L,y6^J!
UserManagerImpl) x{D yTtX<
java代码: Lg8nj< TF
SJD@&m%?[
kEwaT$
/*Created on 2005-7-15*/ 5T sU Qc
package com.adt.service; BA\/YW @
@SCI"H%[
import net.sf.hibernate.HibernateException; %ZHP2j
%~
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import org.flyware.util.page.Page; z/i+EE
f{SB1M
import com.adt.bo.Result; d%l{V6
OL4z%mDZi
/** 8XbA'% o
* @author Joa rG,5[/l
*/ Gt9&)/#
publicinterface UserManager { fw ,\DFHO
ss;R8:5
public Result listUser(Page page)throws .<kqJ|SVi
ge]STSM0n7
HibernateException; 2]% h$f+
ySI~{YVM
} eQQ>
j xYc2
v[Kxja;
H'Yh2a`!o
sz9L8f2
java代码: NcY608C
yf&7P;A
c- .t>r&
/*Created on 2005-7-15*/ @A)R_p
package com.adt.service.impl; JxyB(
)BRKZQN
import java.util.List; r|,i'T
*)+ut(x|#
import net.sf.hibernate.HibernateException; Web|\CH
DBLO|&2!z[
import org.flyware.util.page.Page; ,o]4?-
import org.flyware.util.page.PageUtil; ,t1abp{A
=y=cW1TG
import com.adt.bo.Result; L~ s3b
import com.adt.dao.UserDAO; |HZTN"
import com.adt.exception.ObjectNotFoundException; znJ'iVf
import com.adt.service.UserManager; ?
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/** "?| > btr
* @author Joa {[+2n]f_G
*/ p ;|jI1
publicclass UserManagerImpl implements UserManager { q 4V7
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private UserDAO userDAO; D-,L&R!`
hR.@b*q?R
/** je]}R>[r5
* @param userDAO The userDAO to set. Mg^e3D1_
*/ |{,KRO0P
publicvoid setUserDAO(UserDAO userDAO){ >2By
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this.userDAO = userDAO; Znetzm=0
} F]9nB3:W
Wa?; ^T
/* (non-Javadoc) , lJv
* @see com.adt.service.UserManager#listUser X6^},C'E.:
ApjOj/
(org.flyware.util.page.Page) v(pmIb{
*/ }W
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public Result listUser(Page page)throws Uo-`>7
=~+DUMBT
HibernateException, ObjectNotFoundException { Zy_V9j[n
int totalRecords = userDAO.getUserCount(); "]-Xmdk09
if(totalRecords == 0) 3"{.37Q
throw new ObjectNotFoundException cCR+D.F
mg,j:,
("userNotExist");
GLGz2 ,#
page = PageUtil.createPage(page, totalRecords); #Z5}2soA
List users = userDAO.getUserByPage(page); y9KB< yh/
returnnew Result(page, users); F-*2LMe
} Q~Z=(rP20
T\r@5Xv
} ~.!c~fke
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Y \:0Ev
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M5x U9]B
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 n-TQ*&h]3S
)IJQeC
询,接下来编写UserDAO的代码: rSYi<ku
3. UserDAO 和 UserDAOImpl: }ZqW@-
java代码: j;Z?WXWDh
[=|jZVhT
Ldn8
/*Created on 2005-7-15*/ Zo{$
package com.adt.dao; }E_#k]#*
{f{ZHi|
import java.util.List; BAO| )~1Pd
3 LdQ]S
import org.flyware.util.page.Page; |{@FMxn|q
|$7vI&m
import net.sf.hibernate.HibernateException; 5?Wto4j
Y\0}R,]a-
/** xB !6_VlB
* @author Joa MJ=)v]a
*/ !|<=ZF2
publicinterface UserDAO extends BaseDAO { R
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95<EN(oUD
publicList getUserByName(String name)throws (@#M!'
sZLT<6_B
HibernateException; nW|wY.
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publicint getUserCount()throws HibernateException; _Ob@`
^3hn0DVQ
publicList getUserByPage(Page page)throws 4hw@yTUo
07Edfe
HibernateException; V
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nbG/c80
} !a~`Bs$'jr
jV8q)=}*)
q:<{% U$
2On_'^O
_f6HAGDN
java代码: 1@gg uRF:
2<hpK!R
`EtS!zD~b
/*Created on 2005-7-15*/ Ssk}e=]
package com.adt.dao.impl; A_;8IlW
3<F </
import java.util.List; dik9 >*"|o
+D1 d=4
import org.flyware.util.page.Page; fo4.JyBk
n$[f94d=
import net.sf.hibernate.HibernateException; 6;
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import net.sf.hibernate.Query; &
/4k7X}y
f7I{WfZ\P
import com.adt.dao.UserDAO; ;sch>2&ZWU
3v")J*t
/** 6DZ),F,M
* @author Joa Va$Pi19 O
*/ p!/[K6u
public class UserDAOImpl extends BaseDAOHibernateImpl S!{t6'8K
Uje|`<X
implements UserDAO { VtOZ%h[#
6{qIU}!
/* (non-Javadoc) 6'W [{gzl
* @see com.adt.dao.UserDAO#getUserByName _uc\ D
R
=H<0o?8?c
(java.lang.String) LB/C-n.`
*/ N0>0z]4;q
publicList getUserByName(String name)throws 0 'Vg6E]/
GjB]KA^
HibernateException { f+.T^es
String querySentence = "FROM user in class 1T)Zh+?)}
>\w&6i~
com.adt.po.User WHERE user.name=:name"; al+ #y)+
Query query = getSession().createQuery i*eAdIi
RwVaZJe)l
(querySentence); ,p;_\\<
query.setParameter("name", name); "g+z !4b#
return query.list(); d`d0N5\
} +}Av-47`h
{RB-lfrWs
/* (non-Javadoc) iRi{$.pVJ
* @see com.adt.dao.UserDAO#getUserCount() )~jqW=d
2
*/ -A-tuyIsh"
publicint getUserCount()throws HibernateException { [ $fJRR
int count = 0; V\K<$?oUb
String querySentence = "SELECT count(*) FROM \C5%\4
H.G!A6bd
user in class com.adt.po.User"; vVT?h
Query query = getSession().createQuery f f 7(
&L^CCi
(querySentence); FEz>[#eOX
count = ((Integer)query.iterate().next
fa.0I~
_#o'
+_Z
()).intValue(); O3V.^_k;
return count; X5
ITF)&
} 0@Kkl$O>mb
sCl$f7"
/* (non-Javadoc) nW?R"@Zm
* @see com.adt.dao.UserDAO#getUserByPage Tp<k<uKD
%f8Qa"j
(org.flyware.util.page.Page) ;7Oi! BC
*/ @6o]chJo
publicList getUserByPage(Page page)throws ~YCuO0t
6k?`:QK/sl
HibernateException { T@^]i&
String querySentence = "FROM user in class dV 8iwI
bXM/2Z?6
com.adt.po.User"; HI&kP+,y
Query query = getSession().createQuery zGc(Ef5`M6
NE|[o0On
(querySentence); P,bd'
query.setFirstResult(page.getBeginIndex()) c#xP91.m
.setMaxResults(page.getEveryPage()); t^EhE
return query.list(); [RU
NuO
} /-0'
Qa+*
TOI4?D]
} h7qBp300
DlE_W+F
@kD8^,( oH
G%TL/Z40
&d`^E6#
至此,一个完整的分页程序完成。前台的只需要调用 wX1ig
n<V1|X
userManager.listUser(page)即可得到一个Page对象和结果集对象 )"O{D`uX
POU}/e!Ua
的综合体,而传入的参数page对象则可以由前台传入,如果用 nq`q[KV:
INMP"1
webwork,甚至可以直接在配置文件中指定。 dYOF2si~%
p*;Qz
下面给出一个webwork调用示例: %hT4qzJj
java代码: zREJ#r
:Eh'(
jOtX
60;
/*Created on 2005-6-17*/ m[2'd
package com.adt.action.user; w.kCBDL
J+<p+(^*v
import java.util.List; }WP-W
r!/0 j)
import org.apache.commons.logging.Log; iH)Nk^
import org.apache.commons.logging.LogFactory; DacJ,in_I{
import org.flyware.util.page.Page; E;-qP)yU
T'rjh"C&|
import com.adt.bo.Result; `n-vjjG%#
import com.adt.service.UserService; ~-Oa8ww
import com.opensymphony.xwork.Action; Qd8b-hg
+ Oobb-v
/** RLKj
u;u
* @author Joa `B#Z;R
*/ K=kH%ZK
publicclass ListUser implementsAction{ E5x]zXy4
-0~IY
privatestaticfinal Log logger = LogFactory.getLog 3;BvnD7
q6[}ydV
(ListUser.class); 8&a_A:h
}bfn_ G
private UserService userService; Kd{#r/HZ
}V^e7d
private Page page; cCng5Nq,c
SgSk!lj
privateList users; Fd!iQ
FP;":i RL
/* TU%"jb5
* (non-Javadoc) u:4["ViC
* dF2@q@\.+
* @see com.opensymphony.xwork.Action#execute() w#{l4{X|
*/ tBl#o ^
publicString execute()throwsException{ +L6" vkz
Result result = userService.listUser(page); 91;HiILgT
page = result.getPage(); 5^|"_Q#:
users = result.getContent(); p+D=}O
return SUCCESS; !1-&Y'+
} 8?Wgawx
F^sw0 .b
/** 2
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* @return Returns the page. .v7`$(T
*/ t,?,F4j
public Page getPage(){ 0o;~~\fq.
return page; Kfd _uXL>
} |B|@GF?:
C
>kmIw'
/** #`58F .
* @return Returns the users. p)z-W(
*/ f#mx:Q.7I
publicList getUsers(){ :tlE`BIp
return users; G:hU{S7
} fn?VNZ`J
^cb)f_90
/** V@Kn24''
* @param page #'g^Za
* The page to set. i?W]*V~ply
*/ uA^hCh-js
publicvoid setPage(Page page){ EJ8I[(
this.page = page; aYBTrOd z
} To^#
0
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/** CnQg *+
* @param users 9^p32G
* The users to set. !(yT7#?hP
*/ - &NQ\W
publicvoid setUsers(List users){ =1Ri]b
this.users = users; tU(y~)]
} >.LgsMRIKi
gs-@hR.,s0
/** BMY>a
* @param userService drs-mt8
* The userService to set. Y}K!`~n1S
*/ QjqBO+
publicvoid setUserService(UserService userService){ ,FY-d$3)
this.userService = userService;
[Ek42%
} }D Z)W0RDe
} `i9N)3
X
;Na^]32
=hPG_4#
qj`,qm
P
**.:)
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, l:q8Pg)
d&5c_6oW
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 Q%I#{+OT
?Q;kZmQl
么只需要: UKOFT6|
java代码: ))p$vU3
rAM*\=
{:,_A
<?xml version="1.0"?> ENO? ;
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork xv^Sh}\}
IX"ZS
1.0//EN" "http://www.opensymphony.com/xwork/xwork- eN2dy-0
uC- A43utv
1.0.dtd"> -%>8.#~G
tp%|AD"
<xwork> TeKC} NW
'/ihL^^@L
<package name="user" extends="webwork- ;i.I&*t
tCX9:2c
interceptors"> Wx}M1&d/J
O+p]3u
<!-- The default interceptor stack name 3R'.}^RN
Ir!2^:]!
--> Cy<T Vk8
<default-interceptor-ref Cca6L9%
iD.0J/
name="myDefaultWebStack"/> =Na/3\^WP
u\M4`p!g=
<action name="listUser" =x=1uXQv5
kmmL>fCV"M
class="com.adt.action.user.ListUser"> UHr{
<param 4g>1Gqv6
ZyHIMo|
name="page.everyPage">10</param> ==nYe{2
<result ^CfM|L8>
&aY/eD
name="success">/user/user_list.jsp</result> {-o7w0d_
</action> 6
M*b 6
`@4 2jG}*
</package> c =jcvDQ6W
*Hxj_
</xwork> EW
~*@H
6 lN?) <uQ
/
c+,
W8Ke1(ws&
uG2Xkj
jAA'hA
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*`:M(
<+<)xwOQ ]
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。 ny278tr Q7
Qe7"Z
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 7J0 ^N7"o
U#8\#jo
YnKFcEJrT
`DI{wqV9
%2^['8t#NH
我写的一个用于分页的类,用了泛型了,hoho x%b]ea
H%*~l
java代码: [P.@1mV
w;lx:j!Vp$
cFRSd
}p=
package com.intokr.util; :`{9x%o;
zb@L)%
import java.util.List; /IGrp.}
Q'FX:[@x-S
/** y&n1 Nj]^
* 用于分页的类<br> VFe-#"0ZO
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #gxRTx
* F7k4C2r
* @version 0.01 &>d:ewM\
* @author cheng ,m #@%fa
*/ ?3]h~(=
public class Paginator<E> { /.pa
??u
privateint count = 0; // 总记录数 nG&w0de<>
privateint p = 1; // 页编号 "U/NMGMj
privateint num = 20; // 每页的记录数 F!z! :yp
privateList<E> results = null; // 结果 ,
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rC=p;BC@dD
/** UMHuIA:%U
* 结果总数 wZ
(uq?3S`
*/ kcg)_]~6
publicint getCount(){ r?Ev.m
return count; X}65\6
} S&4w`hdD>~
/u"
cl2|
publicvoid setCount(int count){ #C;#$|d
this.count = count; sg! =Q+
} /ieu)m:2
% xH>0
/** u;l6sdo
* 本结果所在的页码,从1开始 4YU 1Kr4
* [ *mCa:^
* @return Returns the pageNo. 1s^$oi}
*/ U 8qKD
publicint getP(){ 7|{%CckN
return p; Ep v3/`I
} MJ*oeI!.=
yK @X^jf
/** e+]YCp[(
* if(p<=0) p=1 +e{djp@m
* he#Tr'j
* @param p 1*x5/b
*/ ?j^?@%f0
publicvoid setP(int p){ &CPe$'FYI
if(p <= 0) ]aL [
p = 1; D@YM}HXuj
this.p = p; 34O+#0<y~
} j*3sjOoC
V)@nRJ g
/** a3E*%G
* 每页记录数量 G`3vH,
*/ )Or:wFSMq
publicint getNum(){ -*]9Ma<wa
return num; Y
GcY2p<
} .+yJh
sN[@mAoH
/** |L~gNC
* if(num<1) num=1 .q;RNCUt
*/ &55uT;7] a
publicvoid setNum(int num){ "b+3 &i|
if(num < 1) \gPNHL*
num = 1; -7A!2mRiz
this.num = num; 1J!tcj1(
} >f9]Nj
`A}{
I}xq
/** A_4\$NZ^
* 获得总页数 }M"'K2_Z
*/ Y;F,GxR}
publicint getPageNum(){ f*R_\
return(count - 1) / num + 1; #@OKp,LJ
} oqm{<g?2
-iZ js
/** ,:Y=,[ n
* 获得本页的开始编号,为 (p-1)*num+1 ,r)d#8
*/ 66y ,{t
publicint getStart(){ eVbh$cIrZ
return(p - 1) * num + 1; w]}cB+C+l#
} d T-O8
4dD@lG~
/** "9Fv!*<-W
* @return Returns the results. fqp7a1qQl
*/ #| e5
publicList<E> getResults(){ *~aI>7H
return results; :ftyNaq'
} 1oVD Oo
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public void setResults(List<E> results){ C
@[9 LB
this.results = results; ?9.? w-Q'
} xVmUmftD
(h(ZL9!
public String toString(){ x+j/v5
StringBuilder buff = new StringBuilder #cg@Z
a*ixs'MJ
(); }jy7,+
buff.append("{"); K`mxb}
buff.append("count:").append(count); ynz5Dy.d;
buff.append(",p:").append(p); !7Q.w/|=
buff.append(",nump:").append(num); :zk.^q
buff.append(",results:").append ^rZ+H@p:6
OaVL NA^{
(results); m>m`aLrnb
buff.append("}"); wB0WR
return buff.toString(); :zTj"P>"I
} pF{Ri
$7ME a"a
} 7PPsEU:rf
e&I.kC"j6
+hYmL
Sq