Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <g[z jV9p
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 5'lPXKn+L
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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 B
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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 _wq?Pa<)e
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分页支持类: Mbi]EZ
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java代码: *G19fJ[5
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package com.javaeye.common.util; \|;\
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import java.util.List; CXlbtpK2k
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publicclass PaginationSupport { EApKN@<"
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publicfinalstaticint PAGESIZE = 30; eVXXn)>
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privateint pageSize = PAGESIZE; v,KKn\X
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privateList items; ;P@]7vkff
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privateint totalCount; >Fel) a
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privateint[] indexes = newint[0]; >L7s[vKn
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privateint startIndex = 0; / ;]5X
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public PaginationSupport(List items, int rpR${%jc
}#XFa#
totalCount){ ,WT>"9+
setPageSize(PAGESIZE); }Z!D?(
setTotalCount(totalCount); %q {q.(M#
setItems(items); d1j9{
setStartIndex(0); M;(,0d k
} UiFH*HT
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public PaginationSupport(List items, int =&HLz
7|
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totalCount, int startIndex){ G-aR%]7$g
setPageSize(PAGESIZE); M+/xw8}a
setTotalCount(totalCount); 'Uok<;
setItems(items); -3 I3 X
setStartIndex(startIndex); $NXP)Lic)
} wKV4-uyr
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public PaginationSupport(List items, int .Eao|;
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totalCount, int pageSize, int startIndex){ w:~*wv
setPageSize(pageSize); C-'hXh;hQ
setTotalCount(totalCount); x]~TGzS
setItems(items); w0pMH p'Y
setStartIndex(startIndex); NxT"A)u
} K5""%O+
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publicList getItems(){ 2eT?qCxqc
return items; dUI5,3*
} ^J!q>KJs
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publicvoid setItems(List items){ {T){!UVp!
this.items = items; *b~6 B M$
} Cs'LrUB?=U
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publicint getPageSize(){
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return pageSize; nwRltK
} 7e/+C{3v
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publicvoid setPageSize(int pageSize){ 4M'>oa
this.pageSize = pageSize; op,L3:R\Z
} +6m.f,14q
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publicint getTotalCount(){ Qzi?%&
return totalCount; Szu s*YL7
} y_]+;% w:
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publicvoid setTotalCount(int totalCount){ mkl{Tp*
if(totalCount > 0){ ,$P,x
this.totalCount = totalCount; Y+gY"
int count = totalCount / _T=g?0
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pageSize; 4w4B\Na>l
if(totalCount % pageSize > 0) YO6BzS/~
count++; cTqkM@S
indexes = newint[count]; SC{m@
for(int i = 0; i < count; i++){ 1J@Iekat
indexes = pageSize * vqf$("
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i; iCt.rr~;V
} ZzT=m*tQ&
}else{ niVR!l
this.totalCount = 0; !xM5
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} 7*/{m K)
} 5=dL`
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publicint[] getIndexes(){ k$EVr([
return indexes; K|& f5w
} Mf}M/Fh
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publicvoid setIndexes(int[] indexes){ p 7?
this.indexes = indexes; &y[NCAeA
} K%(y<%Xp
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publicint getStartIndex(){ 5{Cz!ut;tE
return startIndex; uOxHa>h
} b}J%4Lx%m
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publicvoid setStartIndex(int startIndex){ 4#U}bN
if(totalCount <= 0) 3Ob.OwA
this.startIndex = 0; R[WiW RfD
elseif(startIndex >= totalCount) |"H 2'L$
this.startIndex = indexes 2wf&jGHs
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[indexes.length - 1]; <v"o+
elseif(startIndex < 0) )P$(]{
this.startIndex = 0; 3} A$+PX
else{ /
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this.startIndex = indexes +)]YvZ6%[,
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[startIndex / pageSize]; :Pud%}'
} c:R?da
} "Fz.#U
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publicint getNextIndex(){ >rnVTK
int nextIndex = getStartIndex() + U"oNJ8&%|
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pageSize; 0.aXg "
if(nextIndex >= totalCount) ]rcF/uQJ<n
return getStartIndex(); '\Xkvi
else EM,C
return nextIndex; MB plhVK8
} T t;F-
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publicint getPreviousIndex(){ =x~I'|%3
int previousIndex = getStartIndex() - Iv`IJQH>
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pageSize; #6sz@X fV
if(previousIndex < 0) *zfgO pK
return0; &&ioGy}1
else %pWn9
return previousIndex; 6iC>CY3CG
} x)5}:b1B=
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} oy+|:[v:Fk
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抽象业务类 )7q$PcY
java代码: [B0BHJ~
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/** qY_qS=H^
* Created on 2005-7-12 yzK;
*/ vSzpx
package com.javaeye.common.business; t0)1;aBZ
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import java.io.Serializable; {@Wv@H+4
import java.util.List; %idBR7?`g
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import org.hibernate.Criteria; 5=>1>HYM
import org.hibernate.HibernateException; 9>}&dQ8
import org.hibernate.Session; '3.\+^3
import org.hibernate.criterion.DetachedCriteria; $:ush"=f8^
import org.hibernate.criterion.Projections; nD
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import "CJVtO
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org.springframework.orm.hibernate3.HibernateCallback; MJn-] E
import _k84#E0
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org.springframework.orm.hibernate3.support.HibernateDaoS ,0l
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upport; l.YE@EL
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import com.javaeye.common.util.PaginationSupport; =C %)(|
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public abstract class AbstractManager extends <'y<8gpM
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HibernateDaoSupport { AGhenDNV
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privateboolean cacheQueries = false; Spm 0`
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privateString queryCacheRegion; V&mkS
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publicvoid setCacheQueries(boolean yR[6s#F/h
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cacheQueries){ ^z,3#gK
this.cacheQueries = cacheQueries; uU
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} *_V+K
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publicvoid setQueryCacheRegion(String :;?$5h*|`
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queryCacheRegion){ + NlnK6T/
this.queryCacheRegion = F>;Wbk&[|
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queryCacheRegion; ~id6^#&>
} 4,RPidv%O
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publicvoid save(finalObject entity){ ;QI9 OcE@/
getHibernateTemplate().save(entity); lu=a e<M
} wMa8HeBE\
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publicvoid persist(finalObject entity){ F)3+IuY
getHibernateTemplate().save(entity); *^>"
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} +VwQ=[y]
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publicvoid update(finalObject entity){ {!,K[QwcI
getHibernateTemplate().update(entity); E'iE#He
} $5nMD=
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publicvoid delete(finalObject entity){ !gh8 Qs
getHibernateTemplate().delete(entity); r$jWjb
} R%r
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publicObject load(finalClass entity, =m.Nm -g
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finalSerializable id){ ;zCUx*{
return getHibernateTemplate().load VcjbRpTy&
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(entity, id); 5es t
} qxZIH
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publicObject get(finalClass entity, Nd8>p.iqO
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finalSerializable id){ 4uF.kz-cg
return getHibernateTemplate().get _^ hg7&dF
ch
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(entity, id); JCWTB`EB>
} "@ >6<(Ki
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publicList findAll(finalClass entity){ X[tt'5
return getHibernateTemplate().find("from s-p)^B
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" + entity.getName()); J4bP(=w!
} j~v`q5X
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publicList findByNamedQuery(finalString Ak[X`e T
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namedQuery){ s5~k]"{j
return getHibernateTemplate c4z&HQd
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().findByNamedQuery(namedQuery); ^O|fw?,
} tYA@J[" ^
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publicList findByNamedQuery(finalString query, 161P%sGx2
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finalObject parameter){ la[pA
return getHibernateTemplate TY8gB!^
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().findByNamedQuery(query, parameter); n%E,[JT
} /HIyQW\Ki-
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publicList findByNamedQuery(finalString query, !h?HfpYv
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finalObject[] parameters){ 'LgRdtO6
return getHibernateTemplate A6(Do]M
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().findByNamedQuery(query, parameters); \'|n.1Fr
} p)biOG
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publicList find(finalString query){ $dM_uSt
return getHibernateTemplate().find BN*:*cmUl
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(query); &'6/H/J
} HZ3;2k
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publicList find(finalString query, finalObject 77\+V 0cF
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parameter){ %q5dV<X'c
return getHibernateTemplate().find [,;Y5#Y[5
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(query, parameter); .7Mf(1:
} ?G `m;S
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public PaginationSupport findPageByCriteria [O3:?BNY
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(final DetachedCriteria detachedCriteria){ ni;)6,i
return findPageByCriteria n)yDep]$G
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); =l(euBb
} v3"6'.f;bY
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public PaginationSupport findPageByCriteria aRTy=~
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(final DetachedCriteria detachedCriteria, finalint [,Ehu<mEK
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startIndex){ $RDlM
return findPageByCriteria IuY9Q8
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(detachedCriteria, PaginationSupport.PAGESIZE, /8;m.J>bf
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startIndex); TcZ.5Oe6h#
} >pu4 G+M
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public PaginationSupport findPageByCriteria HV%/baX]
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(final DetachedCriteria detachedCriteria, finalint 1Uup.(
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pageSize, ]i
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finalint startIndex){ vW?\bH7}I
return(PaginationSupport) I>?oVY6M@u
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getHibernateTemplate().execute(new HibernateCallback(){ AM+5_'S,
publicObject doInHibernate kQkc+sGJf
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(Session session)throws HibernateException { @gN"Q\;F
Criteria criteria = O2fq9%lk
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detachedCriteria.getExecutableCriteria(session); oC`F1!SfOO
int totalCount = :M(uP e=D
!.P||$x`&
((Integer) criteria.setProjection(Projections.rowCount !E$$FvL
,rMDGZm?
()).uniqueResult()).intValue(); <AU*lLZ
criteria.setProjection _ [k
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W
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(null); U:8[%a
List items = t7by OMC
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criteria.setFirstResult(startIndex).setMaxResults w_{tS\
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(pageSize).list(); JuO47}i] 5
PaginationSupport ps = ~,/@]6S&Y
?tYZ/
new PaginationSupport(items, totalCount, pageSize, :)1"yo\
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startIndex); }{R*pmv$bN
return ps; =}Tm8b0
} sD3ZZcy|=
}, true); X&9:^$m
} Z3]I^i
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public List findAllByCriteria(final /\%<VBx ?q
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DetachedCriteria detachedCriteria){ JpS}X\]i
return(List) getHibernateTemplate JP4DV=}L
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().execute(new HibernateCallback(){ ~5,^CTAM
publicObject doInHibernate %:aXEjm@
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(Session session)throws HibernateException { ?%5VaxWJ
Criteria criteria = ,D{7=mDVm
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detachedCriteria.getExecutableCriteria(session); ;M?)-dpZ
return criteria.list(); ]FCP|Jz
} rpKZ>S|7+)
}, true); b,Wm]N
} =zFROB\
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public int getCountByCriteria(final SES.&e|!6
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DetachedCriteria detachedCriteria){ !JA;0[;l=
Integer count = (Integer) Cu7{>"
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getHibernateTemplate().execute(new HibernateCallback(){ h'"m,(a
publicObject doInHibernate Na91K4r#
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(Session session)throws HibernateException { >[ B.y
Criteria criteria = s#Dj>Fej
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detachedCriteria.getExecutableCriteria(session); 2|;|C8C
return
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criteria.setProjection(Projections.rowCount f=^xU
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()).uniqueResult(); <IR#W$[
} e(7#>O%1
}, true); ~A>fB2.pM
return count.intValue(); yz68g?"
} j4IVIj@$`
} =e6pv#
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用户在web层构造查询条件detachedCriteria,和可选的 FW-I|kK.
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 G|,&V0*
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PaginationSupport的实例ps。 [|:{qQyD
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ps.getItems()得到已分页好的结果集 uZ?P{E,K
ps.getIndexes()得到分页索引的数组 vx9!KWy}
ps.getTotalCount()得到总结果数 4AJ] qu
ps.getStartIndex()当前分页索引 JX0M3|I=
ps.getNextIndex()下一页索引 ox&5}&\
ps.getPreviousIndex()上一页索引 S1$^ _S
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 $5pCfW8>
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 r(r(&NU
7 z
一下代码重构了。 8C{&i5kj\E
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我把原本我的做法也提供出来供大家讨论吧: ins(RWO
_%Z.Re
首先,为了实现分页查询,我封装了一个Page类: 5az%yS
java代码: KSs1EmB
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/*Created on 2005-4-14*/ v_zt$bf{Y
package org.flyware.util.page; q=3>ij{v
:[<Y#EX.
/** 4.,EKw3
* @author Joa Lip#uuuXXN
* %gmx47
*/ Bj7*2}
publicclass Page { XH%pV
/[TOy2/;%b
/** imply if the page has previous page */ UIEvwQ
privateboolean hasPrePage; c~U0&V_`j
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/** imply if the page has next page */ ]~;*9`:
privateboolean hasNextPage; LtB5;ByeQ0
?d%)R*3IX
/** the number of every page */ pwN2Nzski
privateint everyPage; Yh95W
qlcd[Y*B
/** the total page number */ e]1=&:eX#d
privateint totalPage; "]"0d[d
kZF]BPh.
/** the number of current page */ \oPe"k=
privateint currentPage; _4>DuklH,
;"&?Okz
/** the begin index of the records by the current %<kfW&_>w
!sX$?P%U
query */ jnqp"
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privateint beginIndex; LGL;3EI
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/** The default constructor */ <pk*z9
public Page(){ IGTO|sT"
zh) &6'S\
} E6GubU
<qR$ `mLN
/** construct the page by everyPage !IOmJpl'
* @param everyPage 6Y2,fW8i,
* */ D#<y
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public Page(int everyPage){ L9/'zhiZBx
this.everyPage = everyPage; )FwOg;=3M"
} 9we];RYK
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/** The whole constructor */ `)a|Q
public Page(boolean hasPrePage, boolean hasNextPage, 4&NB xe
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int everyPage, int totalPage, \!-]$&,j4
int currentPage, int beginIndex){ !po,Z&
this.hasPrePage = hasPrePage; 2- L-=0
this.hasNextPage = hasNextPage; #:" ]-u^
this.everyPage = everyPage; #w L(<nE
this.totalPage = totalPage; I0Do%
this.currentPage = currentPage; p+P@I7V
this.beginIndex = beginIndex; n`=S&oKH
} %# uw8V
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/** DSs/D1mj&
* @return >IQ&*Bb
* Returns the beginIndex. #xmiUN,|
*/ ^(&2
publicint getBeginIndex(){ ^RnQX#+
return beginIndex; Y<;C>Rs
} >> cW0I/`
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/** !}c D e12
* @param beginIndex @16y%]Q-E#
* The beginIndex to set. IRM jL.q
*/ U+VJiz<!
publicvoid setBeginIndex(int beginIndex){ <@`K^g;W
this.beginIndex = beginIndex; ~6#mVP5sU)
} s;h`n$
S*}GW-)oA
/** =3,<(F5Y[
* @return cY} jPDH
* Returns the currentPage. t>]W+Lx#
*/ 5 n 4/}s
publicint getCurrentPage(){ 07^.Z[(pCt
return currentPage; M(8xwo-W
} 4`~OxL
gs2qLb
/** R@WW@ Of
* @param currentPage /,7#%D
* The currentPage to set. *Iw19o-I
*/ ]Q^8
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publicvoid setCurrentPage(int currentPage){ ])pX)(a
this.currentPage = currentPage; R&s/s`pLW
} Jur$O,u40l
0D:uM$
i]
/** @uC-dXA"
* @return aJm5`az)
* Returns the everyPage. &[\zs&[@y
*/ &>B|?d
publicint getEveryPage(){ h<m>S,@g
return everyPage; LzXIqj'H7T
} N0fE*xo
ed,+Slg
/** ,,XHw;{
* @param everyPage w;VUP@Wm
* The everyPage to set. m";8 nm
*/ "~C\Z} ;
publicvoid setEveryPage(int everyPage){ |RpZr!3V
this.everyPage = everyPage; qyyLU@hd
} i_6 wD
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/** oQyMs> g
* @return T5~Qfl?Y
* Returns the hasNextPage. #oGvxc7
*/ ziW[qH {
publicboolean getHasNextPage(){ KJ?/]oLr0
return hasNextPage; TuMZHB7h;
} yyR@kOGga
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/** K6<1&
* @param hasNextPage w*SF Q_6YE
* The hasNextPage to set. #l2WRw_t
*/ bVRxGn @l
publicvoid setHasNextPage(boolean hasNextPage){ h\-jqaq
this.hasNextPage = hasNextPage; [-[|4|CnOm
} fv3)#>Dgp>
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/** [0+5 Gx
* @return zJ0'KHF}o
* Returns the hasPrePage. 8/34{2048
*/ nDC5/xB
publicboolean getHasPrePage(){ qmnCa&C9
return hasPrePage; RDG,f/L2
} I@a7!ugU65
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/** ;LT#/t)}<
* @param hasPrePage Q~*3Z4)j
* The hasPrePage to set. U|h@Pw z
*/ C vTgtZ
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publicvoid setHasPrePage(boolean hasPrePage){ \v_t:
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this.hasPrePage = hasPrePage; 7L:R&W6
}
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/** OaxE3bDT
* @return Returns the totalPage. tX*L_
* Df/f&;`
*/ Q^V`%+
publicint getTotalPage(){ w_J`29uc
return totalPage; >BQF<
} 4sK|l|W
NU/~E"^I.
/** 1[`l`Truz
* @param totalPage nBiA=+'v
* The totalPage to set. s.dn~|a
*/ d0Kg,HB
publicvoid setTotalPage(int totalPage){ ?t.?f`(|
this.totalPage = totalPage; Hp> J,m(*
} L{CHAVkV
l 0b=;^6
} f<'&_*7,|t
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4_I,wG@
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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 ZCJ8I
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个PageUtil,负责对Page对象进行构造: 8UL:C?eY
java代码: #WpO9[b>
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qaGIU`}:$A
/*Created on 2005-4-14*/ fW}H##b
package org.flyware.util.page; =v5(*$"pd"
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import org.apache.commons.logging.Log; 0_y%Qj^e
import org.apache.commons.logging.LogFactory; a
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;09J;sf
/** |]\bgh
* @author Joa +[}]a3)
* /~tfP
*/ 6k3l/ ~R
publicclass PageUtil { fAUsJ[
s*YFN#Wuc
privatestaticfinal Log logger = LogFactory.getLog ujWHO$uz!
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(PageUtil.class); K;xW/7?
ti#sh{t
/** FW.dHvNX
* Use the origin page to create a new page 22r01qH
* @param page O}f(h5!k
* @param totalRecords @Q1jH~t
* @return jh0$:6 `C
*/ nG*6ic
publicstatic Page createPage(Page page, int Z "=(uwM
O.}gG6u5
totalRecords){ tB3CX\e
return createPage(page.getEveryPage(), \+~4t
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page.getCurrentPage(), totalRecords); i:8^:(i
} kL|Y-(FPo%
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/** C[&&.w8Pm
* the basic page utils not including exception v_@_J!s
6uXYZ.A
handler :d2u? +F
* @param everyPage KE&}*Nf[
* @param currentPage qtH&]Suu,
* @param totalRecords pz
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* @return page yl 8v&e{
*/ 4F4u1r+
publicstatic Page createPage(int everyPage, int .M{[J]H`t
.XB] X
currentPage, int totalRecords){ rlIEch^wZ
everyPage = getEveryPage(everyPage); t3>rf3v
currentPage = getCurrentPage(currentPage); YPy))>Q>cK
int beginIndex = getBeginIndex(everyPage, G([vy#p
@!'H'GvA
currentPage); #Fd([Zx#.
int totalPage = getTotalPage(everyPage, bg*{1^
(Sv%-8?gs
totalRecords); RZtL<2.@
boolean hasNextPage = hasNextPage(currentPage, lmcDA,7
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totalPage); `s_TY%&_}g
boolean hasPrePage = hasPrePage(currentPage); QMxz@HGa|
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returnnew Page(hasPrePage, hasNextPage, uRy6~'
everyPage, totalPage, |)-:w?
currentPage, UQcmHZ+lf
V6{xX0'b*m
beginIndex); =|%T E
} w;$+7
qU
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privatestaticint getEveryPage(int everyPage){ 5l}h8So4
return everyPage == 0 ? 10 : everyPage; y4L9Cxvs
} NFc8"7Mz}
7:<Ed"rdE
privatestaticint getCurrentPage(int currentPage){ _MEv*Q@o
return currentPage == 0 ? 1 : currentPage; %S#"pKE6R
} \veL 5
EG.C2]Fi
privatestaticint getBeginIndex(int everyPage, int R7{hoqI2
\IfgL$+
currentPage){ .Cus t
return(currentPage - 1) * everyPage; \8D~,$,``|
} ,R =VzP&
~\G3l,4
privatestaticint getTotalPage(int everyPage, int sD3|Qj;
xH[yIfHkG@
totalRecords){ __iyBaX
int totalPage = 0; \^4$}@*]
(F YJ^o
if(totalRecords % everyPage == 0) <Y2!c,"
totalPage = totalRecords / everyPage; fLoVcl
else ] O>7x
totalPage = totalRecords / everyPage + 1 ; A%2}?Ds
uCfp+
return totalPage; sK?-@
} j2M(W/_
rtx]dc1m
privatestaticboolean hasPrePage(int currentPage){ 6w;|-/:`
return currentPage == 1 ? false : true; )x &@j4,
} hFfaaB
!VZj!\I
privatestaticboolean hasNextPage(int currentPage, ^b %8_?2m
J"%}t\Q
int totalPage){ T_[\(K`w!
return currentPage == totalPage || totalPage == oLMi vy4
& }}WP:U
0 ? false : true; lh_zZ!)g
} I7^X;Q
F
k&s7-yY
PZJ
4:h
} z44~5J]
[B @j@&
ug"<\"
H;|:r[d!
|uBC0f
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。 3og$'#6P
S5KYZ
W
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 _l=
](:FW '-
做法如下: c| ( ?
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~9{;VKgK
>1G*ya)
的信息,和一个结果集List: {taVAcb
java代码: 8G] m7Z
GTe:k
eI rmD
/*Created on 2005-6-13*/ yWi0tE{
package com.adt.bo; :qTcxzV
(<ZkmIXN
import java.util.List; 1DtMY|wP
ko2j|*D6@~
import org.flyware.util.page.Page; ]=VS~azZ5
?}v% JUcs
/** >TnQ4^;v.
* @author Joa |;m`874
*/ 0DVZRB
publicclass Result { &Z!K]OSY
H&Y{jqua
private Page page; Y*cJ4hQ
>-5Gt
private List content; 65#:2,s
?VP!1O=J
/** /
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* The default constructor g^ $11
*/ 33'lZubV
public Result(){ D#Yx,`Ui
super(); Ij}F<ZgZG
} (e3Gs+;
TT ZxkK
/** ;GFB@I@
* The constructor using fields )(Mr f{
* x>,F*3d3
* @param page ]'!xc9KGR
* @param content ~gWd63%8x
*/ S50x0$%<W
public Result(Page page, List content){ I
cR;A\z
this.page = page; h`h>H
X
this.content = content; k7|z$=zY
} G h[`q7B
Q
oA;Ty7s
/** ^h6$>n5
* @return Returns the content. W({TC
*/ H4'DL'83
publicList getContent(){ ''OInfd?
return content; wYO"znd
} b}Hl$V(uD
1m<?Q&|m$
/** G k"L%Zt)
* @return Returns the page. v<3o[m q
*/ Hn9F
gul&
public Page getPage(){ h>Uid
&:?
return page; vo6[2.HS
} .d~]e2x
V l~Y
/** C7 ]DJn
* @param content d9-mWz(V+
* The content to set. '*N9"C
*/ l P$r
public void setContent(List content){ |[owNV>
this.content = content; 7XVzd]jH
} ocl47)
yI.}3y{^5
/** nJ*mEB
* @param page '`]n_$f'
* The page to set. H/Ec^Lc+_
*/ Bq~hV;9nf
publicvoid setPage(Page page){ |v$%V#Bo
this.page = page; \YlF>{LVe
} -M:hlwha
} q]N?@l]
MzR1<W{ O
wHOlj)CZ
o\]:!#r{T
HLSfoQ&)v
2. 编写业务逻辑接口,并实现它(UserManager, FS`vK`'
Dpdn%8+Z
UserManagerImpl) <cDKGd
java代码: C](z#c~c
i'Y'HI
cNuHXaWp
/*Created on 2005-7-15*/ 2&gd"Ak(
package com.adt.service; Cgz&@@j,]
4FIV
import net.sf.hibernate.HibernateException; [Y22Wi
nxyjL)!)0
import org.flyware.util.page.Page; >lraYMc<rZ
8
)mjy!,
import com.adt.bo.Result; `! nJS|
dU ,)TKQ
/** msc 1^2
* @author Joa E[jXUOu-
*/ NV}RRs
publicinterface UserManager { /lLov.
c Q(}^KO
public Result listUser(Page page)throws Xr?>uqY!M
U#;51_
HibernateException; NqJ<!q)
w0 Fwd
} :cc[Jco@w
8%o~4u3
9W1;Kb|Z<
X0y?<G1(a
m<FF$pTT
java代码: C9<4~IM
w
6IEUJ-M Z
F2IC$:e
M
/*Created on 2005-7-15*/ 8To7c
package com.adt.service.impl; ==]Z \jk
G*i.a*9<)
import java.util.List; YXF#c)#
YF}9k
import net.sf.hibernate.HibernateException; B/jrYT$;m
N0=-7wMk(Z
import org.flyware.util.page.Page; .Qd}.EG
import org.flyware.util.page.PageUtil; 89zuL18V
g-."sniP$g
import com.adt.bo.Result; /@&(P#h
import com.adt.dao.UserDAO; `$J'UXtGc
import com.adt.exception.ObjectNotFoundException; / ^w"' '
import com.adt.service.UserManager; jEUx
q%BH
B-!guf
rnY
/** 8NnhT E
* @author Joa z>6.[Z(T
*/ c
Qld$
publicclass UserManagerImpl implements UserManager { u\`/Nhn
"?$L'!bM@
private UserDAO userDAO; A&N$tH
!q!"UMiG
/** ,#
]+HS^B
* @param userDAO The userDAO to set. $zdd=.!KiK
*/ T`uDlo
publicvoid setUserDAO(UserDAO userDAO){ X$/E>I
this.userDAO = userDAO; Iq+2mQi*/k
} I?^aCnU
&a.']!$^"
/* (non-Javadoc) M9gOoYf,~
* @see com.adt.service.UserManager#listUser y)P&]&"?
c8T/4hU
MN
(org.flyware.util.page.Page) Truc[A.2Z
*/ Zw+=ng.q?
public Result listUser(Page page)throws 8pqs?L@W
zei6S
HibernateException, ObjectNotFoundException { ]* 0(-@
int totalRecords = userDAO.getUserCount(); 19'5Re&
if(totalRecords == 0) _0K.Fk*(!
throw new ObjectNotFoundException f6Ml[!aU
=tq1ogE
("userNotExist"); 6VC-KY
page = PageUtil.createPage(page, totalRecords); 4iwf\#
List users = userDAO.getUserByPage(page); {o( *
f
returnnew Result(page, users); G(3;;F7"
} )`^ /(YG
byafb+x
} kL|\wci
rR\;G2p)
EOhC6>ATh
[O\9 9>
"9w}dQ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 &I%IaNco
avg4K*v v
询,接下来编写UserDAO的代码: ^;+[8:Kb
3. UserDAO 和 UserDAOImpl: K!p,x;YX
java代码: R }1W
.@@an;C
$%Z3;:<Uf-
/*Created on 2005-7-15*/ *#zS^b n
package com.adt.dao; m~;B:LN<
CI^[I\$&
import java.util.List; u\f3qc,]F
B_hPcmB
import org.flyware.util.page.Page; mg` j[<wp
tU{\ev$x
import net.sf.hibernate.HibernateException; 8fh4%#,C%
k=`$6(>Fz
/** "CBRPp
* @author Joa #BsW
*/ P].eAAXnP
publicinterface UserDAO extends BaseDAO { `kFiH*5 %z
r_^)1w
publicList getUserByName(String name)throws Tpb"uBiXoo
E~qQai=]
HibernateException; 4^[
/=J}
+pz}4M`
publicint getUserCount()throws HibernateException; >OK#n)U`
z3W3=@
publicList getUserByPage(Page page)throws W&YU^&`Yr
9Sz7\W0
HibernateException; {rDq_^
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} s9i|mVtm8
q*bt4,D&Es
tb,9a!?
P\AqpQv
t+O e)Ns
java代码: ,:UX<6l
R
'C^;OjAg
p?JQ[K7i
/*Created on 2005-7-15*/ Z/g]o#
package com.adt.dao.impl; >?I/;R.-
5$%XvM
import java.util.List; doR4nRl9
'#q4Bc1
import org.flyware.util.page.Page; dxCPV6 XI
H O*YBL
import net.sf.hibernate.HibernateException; [9AM\n>g
import net.sf.hibernate.Query; F?BS717qS%
<( EyXV
import com.adt.dao.UserDAO; RYy,wVh}
pawl|Z'Ez
/** aClA{
* @author Joa g*J@[y;
*/ ~x#vZ=]8
public class UserDAOImpl extends BaseDAOHibernateImpl ugLlI2 nJ
Gq1)1
implements UserDAO { r[pF^y0
Da_()e[9p
/* (non-Javadoc) A[)C:q,
* @see com.adt.dao.UserDAO#getUserByName %j5ywr:
to>
(java.lang.String) -ihiG_f
*/ .T8K-<R
publicList getUserByName(String name)throws G\kpUdj}
4MLH+/e
HibernateException { Oaa"T8t
String querySentence = "FROM user in class (%'9CfPx
.Y\EE;8%
com.adt.po.User WHERE user.name=:name"; Ee)xnY%(
Query query = getSession().createQuery gCJIIzl%Bh
WbcS: !0
(querySentence); 4TZ cc|B5
query.setParameter("name", name); 5FOqv=6S
return query.list(); jDX>izg;V
} -[heV| $;
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/* (non-Javadoc) -c+]Wm"\
* @see com.adt.dao.UserDAO#getUserCount() i=#F)AD^5#
*/ !OAvD#
publicint getUserCount()throws HibernateException { %u!b& 5]e
int count = 0; !MV@)
(.
String querySentence = "SELECT count(*) FROM W5 ec
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user in class com.adt.po.User"; JN(-.8<
Query query = getSession().createQuery uMd. j$$
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(querySentence); pj8azFZ
count = ((Integer)query.iterate().next g7n"
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()).intValue(); BC7 7<R!E)
return count; \Y5W!.(%w
} q-_' W,
Z
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/* (non-Javadoc) 3CZS)
* @see com.adt.dao.UserDAO#getUserByPage z9
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(org.flyware.util.page.Page) sn{tra
*/ Mu&x_&|
publicList getUserByPage(Page page)throws fk{0d
m4m<nnM
HibernateException { DQ80B)<O
String querySentence = "FROM user in class N+g@8Q2s;5
~ap2m
com.adt.po.User"; 6q/?-Qcy
Query query = getSession().createQuery :dwt1>
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(querySentence); J2M(1g)t9
query.setFirstResult(page.getBeginIndex()) $k%Z$NSN=
.setMaxResults(page.getEveryPage()); s\3q!A?S3
return query.list(); 5zB~4 u
} g0&\l}&%U
a9Y5
} @_yoX(.E&
]l;*$2w)
1[PMDS_X
a`c:`v2o
46No%cSiG
至此,一个完整的分页程序完成。前台的只需要调用 A)NkT`<)
2`bdrRD0
userManager.listUser(page)即可得到一个Page对象和结果集对象 (K<9hL+X
l"pN90B4
的综合体,而传入的参数page对象则可以由前台传入,如果用 C+N k"l9
?Bx./t><
webwork,甚至可以直接在配置文件中指定。 ]A+o>#n}x
Es4qPB`g.
下面给出一个webwork调用示例: lpmJLH.F
java代码: ] d?x$>
eJ@~o{,?>
GbZ;#^S
/*Created on 2005-6-17*/ K=\O5#F?3
package com.adt.action.user;
jNyoN1M
#&8rcu;/
import java.util.List; AkBMwV
P'$ `'J]j
import org.apache.commons.logging.Log; u8L$]vOg
import org.apache.commons.logging.LogFactory; I;MD>%[W,
import org.flyware.util.page.Page; fiDl8=~@
V5mTu)tp5
import com.adt.bo.Result; (6gK4__}]
import com.adt.service.UserService; )"<8K}%!
import com.opensymphony.xwork.Action; s8mr''
0L-!!
c3
/** 5iX!
lAFJ
* @author Joa ~)]} 91p
*/ 1vevEa$
publicclass ListUser implementsAction{ ULqoCd%bK
=xN= #
privatestaticfinal Log logger = LogFactory.getLog -:Rp'SJ
EL{vFP
(ListUser.class); nt
:N!suP3
T)iW`vZg8
private UserService userService; S4o$t-9l
tkKJh !Q7
private Page page; {6Au3gt/
rofNZ;nu
privateList users; [iS$JG-
xL
"!~dN
/* 5Fw - d
* (non-Javadoc) }IaA7f
* kLP0{A
* @see com.opensymphony.xwork.Action#execute() \2v"YVWw
*/ nv/[I,nw
publicString execute()throwsException{ 7/IlL
Result result = userService.listUser(page); 3iNkoBCg
page = result.getPage(); $lwz-^1t.
users = result.getContent(); )%Iv[TB[
return SUCCESS; YwDt.6(+,
} ^QXbJJ
Bi%x`4Lf
/** 1NLg _UBOK
* @return Returns the page. `ldz`yu6++
*/ Me3dpF
public Page getPage(){ 2DDsWJ;
return page; \?fI t?
} }
p:%[
%&<LNEiUN
/** ;{Ux_JEg
* @return Returns the users. \IM4Z|NN"
*/ mEAXM1J|
publicList getUsers(){ p*3; hGp6
return users; Sv[ 5NZn0&
} &(pjqV
Lxl_"kG
/** I:j3sy
* @param page ~mz%E
* The page to set. @mQ:7-,~
*/ /F/;G*n
publicvoid setPage(Page page){ S~OhtHwK
this.page = page; E /<lGm:.
} 3R$Z[D-
'Prxocxq
/** Ri*3ySyb
* @param users 2[yBD-":
* The users to set. N:5[,O<m_
*/ |UUdz_i!:
publicvoid setUsers(List users){ P5<vf
this.users = users; aoW6U{\
} <yUstz,Xu^
Yl cbW0'c
/** V*[b}Xew
* @param userService afG{lWE)
* The userService to set. ~.g3ukt
*/ 8MwK.H[U
publicvoid setUserService(UserService userService){ ts~{w;c
this.userService = userService; [1G^/K"
}
#/S
{6c
} gXFWxT8S
cI0 ]}S
d9^E.8p$
30j|D3-
?=Pd
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, vw>j J
n$L51#'
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 uzr\oj+>
Zo-$z8
么只需要: 3(E
$I5
java代码: "f.Z}AbP
IZ,oM!Y
|,C#:"z;
<?xml version="1.0"?> }WLh8i?_
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork l ,|%7-
a6xj\w
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 7*+]wEs
>p\e0n
1.0.dtd"> )(M7lq.e7
&]6)LFm
<xwork> gxNL_(A
<=K qcHb
<package name="user" extends="webwork- $D1w5o-
RBKOM$7
interceptors"> :*514N
]jMKC8uz
<!-- The default interceptor stack name dtStTT
S^I,Iz+`S'
--> Dr<='Ux[5
<default-interceptor-ref k`KGB
<!d"E@%v@
name="myDefaultWebStack"/> f>j wN@(
+|cI:|H>
<action name="listUser" >TL^>D
b&)5:&MI
class="com.adt.action.user.ListUser"> }j 5 a[L
<param ;!>Wz9
Xf'=+f2p
name="page.everyPage">10</param> `(y(w-:W1
<result p&p.Q^"ok
gJN0!N'
name="success">/user/user_list.jsp</result> dIweg=x
</action> t:~t@4j}
UKd'+R]
</package> 2.uA|~qH
1k8x%5p
</xwork> 9Ru;`
uLeRZSC
5v.DX`"
<~U4*
gwkb!#A
|H}sYp
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 kK>X rj6
|iYg >
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 zSTR^sgJ
qeL pXe0c
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ,*id'=S
F'8T;J7
>T3H qYX5W
&Nl2sey
\5
pu|2u
我写的一个用于分页的类,用了泛型了,hoho Fe&qwq"
}alj[)
java代码: <~emx'F|
}3 m0AQ;K
[onqNp
package com.intokr.util; BbOu/i|
0X|_^"!
import java.util.List; GV|9H]_,I
shC;hR&;
/** :t$aN|>y
* 用于分页的类<br> ihe(F7\U
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 9v)%dO.
* bKVj [r8D~
* @version 0.01 is;XmF*5=
* @author cheng O>y'Nqz
*/ MhEw
_{?
public class Paginator<E> { !eR3@%4
privateint count = 0; // 总记录数 rZ1Hf11C
privateint p = 1; // 页编号 !c W[G/W8
privateint num = 20; // 每页的记录数 k_|^ kdWJ
privateList<E> results = null; // 结果 -cF'2Sfr
~,6b_W p/
/** 5AeQQU
* 结果总数 oP?YA-#nc
*/ OKOu`Hz@
publicint getCount(){ yoe}$f4
return count; imL_lw^?
} b;mSQ4+
\uOdALZ
publicvoid setCount(int count){ h[tix:
this.count = count; X&m'.PA
} U]~^Z R
:&XH?/Wi
/** u`:hMFTID
* 本结果所在的页码,从1开始 Gi6T["
* Xk mQBV"
* @return Returns the pageNo. ;$j7H&UNQj
*/ #C*8X+._y
publicint getP(){ !LM<:kf.|
return p; .0HZNWRtb
} ]uL+&(cr
xG&SX#[2
/** +#J,BKul
* if(p<=0) p=1 dj6*6qX0'^
* +V862R4,o
* @param p q~K(]Ya/
*/ @JkK99\(>9
publicvoid setP(int p){ qk(P>q8[
if(p <= 0) g+8hp@a
p = 1; 1n*W2:,z
this.p = p; AN:@fZ
} Pi2|
;!@EixN-YH
/** =ziwxIo6
* 每页记录数量 FE7)E.U
*/ rEZ8eeB[3
publicint getNum(){ 5
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return num; [ee%c Xo
} cp
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qAkx<u
/** h #Z4pN8T3
* if(num<1) num=1 Br>Fpe$q4
*/ 4b]a&_-}
publicvoid setNum(int num){ %~|HFYd
if(num < 1) "%2xR[NF
num = 1; h:\oly\
this.num = num; 2 -!L _W(
} Ft JjY@#
M&Y .;
/** tCF&OOI4`
* 获得总页数 cF T 9Lnz
*/ {4 >mc'dv
publicint getPageNum(){ bEuaOBc
return(count - 1) / num + 1; R!
s6% :Yg
} oSb, :^Wl
9X<OJT;3J
/** ;)0w:Zn/[
* 获得本页的开始编号,为 (p-1)*num+1 PG5- ;i/
*/ 0pe3L
publicint getStart(){ +0z 7KO%^^
return(p - 1) * num + 1; d?,M/$h
} :B*}^g
uUR~&8ERX
/** M<?Q4a'Q
* @return Returns the results. 2h30\/xkU
*/ ^>4o$}
publicList<E> getResults(){ OvL\u{(<F
return results; %rKK[
} >:sUL<p
tS# `.F~y
public void setResults(List<E> results){ 5 +9Ze9
this.results = results; :bU(S<%M
} c/W=$3
RWq{Ff}Hk
public String toString(){ /G{_7cb
StringBuilder buff = new StringBuilder Jwn AW}=
f6<g3Q7Mu
(); `xS{0P{uj
buff.append("{"); t-%Q`V=[
buff.append("count:").append(count); [V#r7a
buff.append(",p:").append(p); n;XWMY
buff.append(",nump:").append(num); I~eSZ?$s#
buff.append(",results:").append Z-=YM P ]Q
<S"~vKD'
(results); I XA>`D
buff.append("}"); (n(
fI f
return buff.toString(); z;u>
Yz+3
} 0CvsvUN@
z T%U!jqI
} yTM{|D]$(
L7Dh(y=;7
J a,d3K