Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Y\xEPh
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 mvn- QP~"
Spm 0`
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 w,{h9f
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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 Xr*I`BJ
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。 W/'1ftn?D
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分页支持类: j,n:%5P\v
9#8vPjXW}.
java代码:
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package com.javaeye.common.util; A#U! KX
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import java.util.List; L*z=!Dpo
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publicclass PaginationSupport { 5K vp%
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publicfinalstaticint PAGESIZE = 30; F^UtZG+
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privateint pageSize = PAGESIZE; T"wg/mT
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privateList items; Om3Ayk}
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privateint totalCount; ^WA7X9ed
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privateint[] indexes = newint[0]; $]7f1U_e
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privateint startIndex = 0; ]#0 (
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public PaginationSupport(List items, int l9K`+c+t
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totalCount){ RpdUR*K9x
setPageSize(PAGESIZE); !'f7;%7s
setTotalCount(totalCount); ^[<BMk
setItems(items); Pnytox
setStartIndex(0); ^eW<-n@^
} BabaKSm}LP
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public PaginationSupport(List items, int Nd8>p.iqO
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totalCount, int startIndex){ {}$9
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setPageSize(PAGESIZE); -CPtYG[s
setTotalCount(totalCount); _p$/.~Xo9
setItems(items); \o<ucp\J
setStartIndex(startIndex); 3,PR6a,b'
} -^&=I3bp
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public PaginationSupport(List items, int <2U#U;
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totalCount, int pageSize, int startIndex){ dT|XcVKg
setPageSize(pageSize); =<]`'15"V
setTotalCount(totalCount); J 8i;E4R
setItems(items); vQWmHv\P
setStartIndex(startIndex); _i_='dsyW/
} ljFq ;!I5
PV68d; $:8
publicList getItems(){ ki1(b]rf
return items; x0 j5D
} P&`%VW3E
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publicvoid setItems(List items){ Ejug2q
this.items = items; =\Q<TY
} *-0s
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publicint getPageSize(){ Q2
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return pageSize; e5_Hmuk|
} 4`O[U#?
w>W #cTt
publicvoid setPageSize(int pageSize){ 20Zxv!
this.pageSize = pageSize; <AgB"y@
} M}]
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publicint getTotalCount(){ SxF'2ii
return totalCount; aH}/+Hu-
} $6Ma{r C|
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publicvoid setTotalCount(int totalCount){ *aErwGLB8
if(totalCount > 0){ .W]k8N E
this.totalCount = totalCount; l!ow\ZuQBF
int count = totalCount / Av x`
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pageSize; St5;X&Q
if(totalCount % pageSize > 0) wFMH\a
count++; ERPg TZT
indexes = newint[count]; #]h
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for(int i = 0; i < count; i++){ APu$t$dmm
indexes = pageSize * -YNpHd/;,
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i; #j2kT
} k>&cHCS`*
}else{ =.`\V]
this.totalCount = 0; 7@@g|l]
} gvP-doA7W
} N~/'EaO
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publicint[] getIndexes(){ @]qP:h.
return indexes; kf@JEcKV
} 1PY]Q{r
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publicvoid setIndexes(int[] indexes){ aRTy=~
this.indexes = indexes; 're:_;lG
} FJn-cR.n
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publicint getStartIndex(){ $+j1^
return startIndex; X}( s(6
} 4/
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publicvoid setStartIndex(int startIndex){ h$5[04.Q
if(totalCount <= 0) U7WYS8
this.startIndex = 0; y[N0P0r l:
elseif(startIndex >= totalCount) B*tYp
this.startIndex = indexes c64^u9
YR'F]FI
[indexes.length - 1]; l'I:0a
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elseif(startIndex < 0) izP)t
this.startIndex = 0; C0N
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else{ l"ms:v
this.startIndex = indexes B[8bkFS>]
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[startIndex / pageSize]; q7 PCMe
} ^N7H~CT"
} k;\gYb%L
*)K\&h<{
publicint getNextIndex(){ 1L,L/sOwB&
int nextIndex = getStartIndex() + pU_3Z3CeE
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pageSize; vM/*S
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if(nextIndex >= totalCount) 3(c-o0M
return getStartIndex(); `,]Bs*~
else `X<B+:>v-
return nextIndex; jn^X{R\
} 7^><Vh"qV
6]v}
publicint getPreviousIndex(){ ~5,^CTAM
int previousIndex = getStartIndex() - c)#P}Ai
=TD`P et
pageSize; Z:9 Q~}x8
if(previousIndex < 0) {R_>KE1
return0; TAXsL&Tz>
else m,)s8_a
return previousIndex; [v~,|N>w
} coAXYn
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} lp}S'^ y
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抽象业务类 Gd!-fqNa'x
java代码: ?Ek)" l
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/** `n$Ak5f
* Created on 2005-7-12 Z1 Nep!
*/ u ON(LavB
package com.javaeye.common.business; r,;ca6>5H
DMUirA;
import java.io.Serializable; +Kk1[fh-
import java.util.List; 8n3]AOc'~-
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import org.hibernate.Criteria; <IR#W$[
import org.hibernate.HibernateException; (~DW_+?]'
import org.hibernate.Session; 9w-\K]
import org.hibernate.criterion.DetachedCriteria; *s4|'KS2o
import org.hibernate.criterion.Projections; [Vs\r&qL
import ,)`_?^\$f
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org.springframework.orm.hibernate3.HibernateCallback; i >3`V6
import ?W'z5'|
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org.springframework.orm.hibernate3.support.HibernateDaoS DZ|*hQU>K
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upport; w*`:v$
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import com.javaeye.common.util.PaginationSupport; g`pq*D
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public abstract class AbstractManager extends ZeV@ X
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HibernateDaoSupport { ZN8j})lE
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privateboolean cacheQueries = false; =2&\<Q_Fi
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privateString queryCacheRegion; 'OnfU{Ai
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publicvoid setCacheQueries(boolean Xz4q^XJ
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cacheQueries){ MT/jpx
this.cacheQueries = cacheQueries; :^y!z1\2(7
} lgews"
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publicvoid setQueryCacheRegion(String kgo#JY-4
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queryCacheRegion){ r6FTpOF
this.queryCacheRegion = llZU: bs
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queryCacheRegion; {L;sF=d
} ;VLDXvGd
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publicvoid save(finalObject entity){ G`l\R:Q
getHibernateTemplate().save(entity); Lip#uuuXXN
} Ii+3yE@c
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publicvoid persist(finalObject entity){ P8m0]T.&x
getHibernateTemplate().save(entity); e=9/3?El
} i\CA6I
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publicvoid update(finalObject entity){ wm@j(h4
getHibernateTemplate().update(entity); Onx6Fy]L
} 3#t9pI4
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publicvoid delete(finalObject entity){ #ksDU
getHibernateTemplate().delete(entity); $^Xxn.B9
} ~) ;4O8~.
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publicObject load(finalClass entity, Owf!dMA;nF
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finalSerializable id){ VVQ~;{L
return getHibernateTemplate().load Fizrsr 6%
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(entity, id); p&Qb&nWk<
} .OJGo<#$f
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publicObject get(finalClass entity, F/2cQ.u2
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finalSerializable id){ r $S9/
return getHibernateTemplate().get 2xN7lfu1RB
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(entity, id); 3}}/,pGSc
} tEL;,1
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publicList findAll(finalClass entity){ b=Nsz$[
return getHibernateTemplate().find("from !5d n7Wuj
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" + entity.getName()); %ZoJu
} n@`3O'S
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publicList findByNamedQuery(finalString <l1/lm<#
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namedQuery){ 7Q/H+)
return getHibernateTemplate \y7?w*K
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().findByNamedQuery(namedQuery); !po,Z&
} Mh`^-*c?
#:" ]-u^
publicList findByNamedQuery(finalString query, #w L(<nE
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finalObject parameter){ p+P@I7V
return getHibernateTemplate n`=S&oKH
^U~Er'mT
().findByNamedQuery(query, parameter); E{6ku=2F
} k?h{6Qd
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publicList findByNamedQuery(finalString query, NATi)A"TZ
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finalObject[] parameters){ .U(6])%;@
return getHibernateTemplate iY>xx~V
#4|RaI|.
().findByNamedQuery(query, parameters); !$HuH6_[
} 05ZYOs }
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publicList find(finalString query){ .:H'9QJg
return getHibernateTemplate().find %;4#?.W8
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(query); wSjy31
} ZS:[ZehF
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publicList find(finalString query, finalObject =3,<(F5Y[
cY} jPDH
parameter){ t>]W+Lx#
return getHibernateTemplate().find K/(LF}
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(query, parameter); M(8xwo-W
} 4`~OxL
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public PaginationSupport findPageByCriteria `*CoVx~fk
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(final DetachedCriteria detachedCriteria){ \nOV2(FAT
return findPageByCriteria r;f\^hVy
HV`u#hZ7C
(detachedCriteria, PaginationSupport.PAGESIZE, 0); &h[)nD
} G%gdI3h1Z
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public PaginationSupport findPageByCriteria yzpa\[^
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(final DetachedCriteria detachedCriteria, finalint WL%T nux
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startIndex){ y%--/;
return findPageByCriteria @lB1t=
D
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(detachedCriteria, PaginationSupport.PAGESIZE, A f?&VD4K
XF{2'x_R
startIndex); LzXIqj'H7T
} N0fE*xo
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public PaginationSupport findPageByCriteria ,,XHw;{
w;VUP@Wm
(final DetachedCriteria detachedCriteria, finalint m";8 nm
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pageSize, 0T3r#zQ
finalint startIndex){ qyyLU@hd
return(PaginationSupport) ,_,7cor
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getHibernateTemplate().execute(new HibernateCallback(){ \i~5H]?d
publicObject doInHibernate tSDp>0yZ3
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(Session session)throws HibernateException { -NG9?sI\U
Criteria criteria = =L$RY2S"
"z.!h(Eq
detachedCriteria.getExecutableCriteria(session); y^p%/p%
int totalCount = @Ng q+uXm
j@Us7Q)A(
((Integer) criteria.setProjection(Projections.rowCount nkk GJV!
suj}A
()).uniqueResult()).intValue(); jaThS!>v
criteria.setProjection t[%=[pJHW
QL(}k)dB
(null); `).;W
List items = 0txSF^x
9DXu*}
criteria.setFirstResult(startIndex).setMaxResults ]:^kw$
d@|j>Z
(pageSize).list(); '9wD+'c=A
PaginationSupport ps = s|!b: Ms`
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new PaginationSupport(items, totalCount, pageSize, ;`bJgSCfo
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startIndex); U|h@Pw z
return ps; C vTgtZ
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} \v_t:
"
}, true); 7L:R&W6
}
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public List findAllByCriteria(final Y@%6*uTLa
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DetachedCriteria detachedCriteria){ ;Wr,VU]
return(List) getHibernateTemplate Vo2frWF$
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().execute(new HibernateCallback(){ ]*;+ U6/?
publicObject doInHibernate "=!QSb
{&(bKQ
(Session session)throws HibernateException { ]O&A:Us
Criteria criteria = +ACV,GG
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detachedCriteria.getExecutableCriteria(session); e;}5~dSi
return criteria.list(); >Q\H1|?
}
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}, true); J=]w$e ?.P
} Zr2QeLQC(
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public int getCountByCriteria(final 2|w.A!
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DetachedCriteria detachedCriteria){ ~(0Y`+gC
Integer count = (Integer) CM's6qhQnn
)@`w^\E_~_
getHibernateTemplate().execute(new HibernateCallback(){ Q+ST8
publicObject doInHibernate KF-gcRh
\ZDT=?
(Session session)throws HibernateException { yM D*>8/
Criteria criteria = lB\j>.c
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detachedCriteria.getExecutableCriteria(session); Q}Vho.N@=
return !%M-w0vC9
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criteria.setProjection(Projections.rowCount |QgXSe7
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()).uniqueResult(); R;V(D3
} 5BCaE)J
}, true); 'Jl.fN
return count.intValue(); ~ pdf'
} mg,f> (
} @x J^JcE
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用户在web层构造查询条件detachedCriteria,和可选的 m<f{7]fi5
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 E:E&Wv?r
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PaginationSupport的实例ps。 /eMZTh*1P
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ps.getItems()得到已分页好的结果集 {4m"S7O
ps.getIndexes()得到分页索引的数组 a&ByV!%%+_
ps.getTotalCount()得到总结果数 2nieI*[
ps.getStartIndex()当前分页索引 fY"28#
ps.getNextIndex()下一页索引 EhUy7b,1_
ps.getPreviousIndex()上一页索引 RK3/!C`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /[IQ:':^
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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 \mu9ikZ<
,]{NZ9
一下代码重构了。 EXFxiw
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我把原本我的做法也提供出来供大家讨论吧: *f#4S_ws`
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首先,为了实现分页查询,我封装了一个Page类: jrl6):x
java代码: E\*",MGL
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/*Created on 2005-4-14*/ \
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package org.flyware.util.page; PC_4#6^5
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/** $B?7u@>,
* @author Joa D5m\u$~V
* VfcQibm
*/ lmcDA,7
publicclass Page { `k|nf9_
G!;[If:<e
/** imply if the page has previous page */ u.=;A#
privateboolean hasPrePage; J|
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yrs3`/
/** imply if the page has next page */ y&Hh8|'mC
privateboolean hasNextPage; OA=;9AcZ
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/** the number of every page */ Aii[=x8
privateint everyPage; .KsvRx
FOA%(5$4
/** the total page number */ Wu&Di8GhP
privateint totalPage; M<srJ8|'
w1_Ux<RF
/** the number of current page */ MX0B$yc$
privateint currentPage; T!a[@,)_
RGLA}|
/** the begin index of the records by the current RHbp:Mlk
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query */ cj<@~[uw
privateint beginIndex; gAY2|/,
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/** The default constructor */ (Qm;]?/
public Page(){ ,R =VzP&
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} m^.C(}
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/** construct the page by everyPage 1F,_L}=o1s
* @param everyPage y21uvp'
* */ i=oa"^c4
public Page(int everyPage){ WCu%@hh=h
this.everyPage = everyPage; ,GnU]f
} z0[ZO1Fo(
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/** The whole constructor */ RWo B7{G
public Page(boolean hasPrePage, boolean hasNextPage, B-|Zo_7
\Agg6tYr
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int everyPage, int totalPage, N=wy)+
int currentPage, int beginIndex){ y}HC\A77uD
this.hasPrePage = hasPrePage; KgWT&^t
this.hasNextPage = hasNextPage; p ri{vveN@
this.everyPage = everyPage; =3C)sz}
this.totalPage = totalPage; NF!1)
this.currentPage = currentPage; +:%FJCOT
this.beginIndex = beginIndex; K>6k@okO
} s*~o%emw
*$C[![
/** yWtr,
* @return u(Sz$eV
* Returns the beginIndex. a?~csP^?}
*/ ONiI:Z>%
publicint getBeginIndex(){ 9 lJj/
return beginIndex; -$t,}3
} am+mXb
ha! "BR
/** CZRo{2!?U
* @param beginIndex \Egc5{
* The beginIndex to set. (v:ek_
*/ !F#aodM1N
publicvoid setBeginIndex(int beginIndex){ qjzW9yV+
this.beginIndex = beginIndex; wP0+Xv,
} c@7hLUaE2
ld}$Tsy0
/** A i){,nh`0
* @return GPLt<K!<#
* Returns the currentPage. '2$!thm
*/ eI rmD
publicint getCurrentPage(){ yWi0tE{
return currentPage; :qTcxzV
} *;E+9^:V
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/** :yjK*"T|OD
* @param currentPage ZCFf@2&z8
* The currentPage to set. eSNSnh]'
*/ xcvr D
publicvoid setCurrentPage(int currentPage){ '#PqI)P
this.currentPage = currentPage; wKS-O%?
} gam#6
s
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/**
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* @return \Fg6b6
* Returns the everyPage. yPh2P5}H>
*/ ,nB3c5X)|
publicint getEveryPage(){ IKzRM|/
return everyPage; 8{SU?MHQLE
} G? gXK W
D *I;|.=u
/** 355Sd;*
* @param everyPage D>b5Uwt
* The everyPage to set. n,a5LR
*/ x>,F*3d3
publicvoid setEveryPage(int everyPage){ ]'!xc9KGR
this.everyPage = everyPage; ~gWd63%8x
} apD=>O
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/** J2<
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* @return [7Lxt
* Returns the hasNextPage. tb?F}MEe
*/ DwY<qNWT
publicboolean getHasNextPage(){ ,o@~OTja*
return hasNextPage; 27E9NO=
} O0wCb
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/** ;s\;78`0
* @param hasNextPage
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* The hasNextPage to set. \btR^;_\A
*/ #>m,
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publicvoid setHasNextPage(boolean hasNextPage){ ;[KriW
this.hasNextPage = hasNextPage; `o8{qU,*]N
} =6Sj}/
n~)HfY
/** rH&r6Xv[
* @return s'aV q B
* Returns the hasPrePage. q bZ,K@0
*/ s w.AfRQP
publicboolean getHasPrePage(){ EhIV(q9x
return hasPrePage; seuN,jpt
} Yl&tkSw46
FfxX)p1t
/** SQt|(r)
* @param hasPrePage wL-ydMIx
* The hasPrePage to set. _m7U-;G
*/ o d}EM_
publicvoid setHasPrePage(boolean hasPrePage){ vf'cx:m
this.hasPrePage = hasPrePage; OVUs]uK
} Xm8Z+}i
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/** @bW[J
* @return Returns the totalPage. v-;XyVx
* \%Ah^U)gS
*/ rI<nUy P?
publicint getTotalPage(){ ?wLdW1&PpX
return totalPage; :Dk@?o@2;C
} r!.+XrYg
i,'Ka[6
/** O| 1f^_S/
* @param totalPage ^s2m\Q(
* The totalPage to set. _[TH@fO6:
*/ 'o/N}E!Pt
publicvoid setTotalPage(int totalPage){ P('t6MVlT
this.totalPage = totalPage; "s>fV9YyZ
} C'-zh\a
OHHNWg_5
} ," C[Qg(
y^X\^Kq
XJmFJafQD
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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 &R'w-0k_
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个PageUtil,负责对Page对象进行构造: N4a`8dS|
java代码: my\o P(e\
oI_oz0nHk
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/*Created on 2005-4-14*/ F<yy>Wf
package org.flyware.util.page; q}<.x8\
1iNsX\M
import org.apache.commons.logging.Log; oNuPP5d[]
import org.apache.commons.logging.LogFactory; \6SMn6a4
PG6[lHmi
/** X(GmiH /E
* @author Joa C#Hcv*D
* ~5r=FF6
*/ Ig1lol:;
publicclass PageUtil { <H5n>3#pH
aFRTNu/r
privatestaticfinal Log logger = LogFactory.getLog 9Qzjqq:"Li
" WYA
(PageUtil.class); NZo<IKD$
<I7(eh6d
/** 5c:'>
* Use the origin page to create a new page IjG5X[@
* @param page cq*p9c
* @param totalRecords _m9~*
* @return b:P\=k]8#
*/ 2Vp>"
publicstatic Page createPage(Page page, int X,RT<GNNb
m<FF$pTT
totalRecords){ ${hyNt
return createPage(page.getEveryPage(), R9tckRG#
O9t=lrYV!
page.getCurrentPage(), totalRecords); SkiJpMN
} 7fTxGm
!uWxRpT,7
/** cVQatm
* the basic page utils not including exception &sm
@
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handler 'FShNY5
* @param everyPage t|;%DA)fjw
* @param currentPage XVQL.A7
* @param totalRecords ?^LG
hdR
* @return page |EF>Y9
*/ b/}'Vf[
publicstatic Page createPage(int everyPage, int <9ma(PFa
)K{o<m~WAo
currentPage, int totalRecords){
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everyPage = getEveryPage(everyPage); uuu\f*<
currentPage = getCurrentPage(currentPage); "_ LkZBW.
int beginIndex = getBeginIndex(everyPage, 7{n\yl?
:3*`IB !
currentPage); )fNGB]%
int totalPage = getTotalPage(everyPage, C/F@ ]_y
L)q`D2|'
totalRecords); @&?a]>L
boolean hasNextPage = hasNextPage(currentPage, W|;nJs:e
/ ^w"' '
totalPage); a*Rz<08
boolean hasPrePage = hasPrePage(currentPage); 3PfiQ|/b
<z^SZ~G
returnnew Page(hasPrePage, hasNextPage, XjX 2[*l
everyPage, totalPage, +x(YG(5\w
currentPage, @. "q
gf+o1\5t@
beginIndex); X(IyvfC
} xb%/sz(4
43KaL(
privatestaticint getEveryPage(int everyPage){ +Dv 7:x7
return everyPage == 0 ? 10 : everyPage; e\`wlaP,
} z~F37]W3[
p`
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privatestaticint getCurrentPage(int currentPage){ Iq+2mQi*/k
return currentPage == 0 ? 1 : currentPage; I?^aCnU
} StEQ
-k
!?jK1{E3
privatestaticint getBeginIndex(int everyPage, int 21U&Ww
>yX/+p_
currentPage){ -:MmSeG7gO
return(currentPage - 1) * everyPage; $u:<x
} O47PkP8
jQ6Xr&}
privatestaticint getTotalPage(int everyPage, int Tj=gRQ2v
UL&} s_
totalRecords){ > 84e`aGE
int totalPage = 0;
4bnt=5]
W/sY#"
if(totalRecords % everyPage == 0) RF:04d
totalPage = totalRecords / everyPage; @9aGz6k+
else h{I`7X
totalPage = totalRecords / everyPage + 1 ; /w0sj`;"
a_Jb>}
return totalPage; *m*`}9
} Wu ,S\!
CA/ -Gb
privatestaticboolean hasPrePage(int currentPage){ E-^2"j>o
return currentPage == 1 ? false : true; 2SYKe$e
} Hj2<ZL
Hoj8okP
privatestaticboolean hasNextPage(int currentPage, vTdUuj3N
sJOV2#r
int totalPage){ >
V8sm/M
return currentPage == totalPage || totalPage == M;qBDT~)
)Bo]=ZTJ^
0 ? false : true; gSb,s [p&+
} d ,UCH
NddO*`8+)
>Co)2d]
} e^zHw^js
opXDm\
[,rn3C A
(Izf
L1
mg` j[<wp
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。 ;`+`#h3-V
m^Glc?g<
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 4Ac}(N5D@
j1A|D
做法如下: !.*iw
k`
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 L!,d"wuD
X &D{5~qC
的信息,和一个结果集List: NEw$q4
java代码: 4^[
/=J}
t{zBC?cR
*jE;9^
/*Created on 2005-6-13*/ ->h5T%sn
package com.adt.bo; h,t:]
QXs8:;T
import java.util.List; q6REh;$
B)M&\:
_
import org.flyware.util.page.Page; &pL/
@2+
l[oe*aYN7
/** Lc|{aN
* @author Joa s9i|mVtm8
*/ q*bt4,D&Es
publicclass Result { >g]ON9CGH
Plfdr~$
private Page page; N'QqJe7Z
!p',Za
private List content; 7\X$7
{~_Y _-
/** Bd&`Xfebj
* The default constructor WI&lj<*
*/ gw+eM,Yp
public Result(){ CW p#^1F
super(); k3>YBf`fC
} W:vr@e6
[9AM\n>g
/** F?BS717qS%
* The constructor using fields cDIBDC
* 6e.[,-eU
* @param page APq7 f8t
* @param content @^&7$#jq%
*/ mlB~V3M'G
public Result(Page page, List content){ moZm0`WR
this.page = page; ~8{sA5y
this.content = content; KP{3iUqvO
} _{)9b24(
s$ z2 c
/** N 9LgU)-Jt
* @return Returns the content. u okc:D
*/ /8c&Axuv
publicList getContent(){ -{{[cTI
return content; R/~,i;d>
} 0%#\w*X8
N=~~EtX
/** 2+Yb
7 uI,
* @return Returns the page. e <"/'Ql!k
*/ #K|9^4jt
public Page getPage(){ 50$W0L$
return page; )/>A6A:
} ~*-qX$gr
+qy6d7^
/** U\vY/6;JI
* @param content g`[$XiR
* The content to set. R\O.e
*/ x+7*ADKb
public void setContent(List content){ tJ'iX>9I
this.content = content; snC/H G7
} 7u|B ](FS
>bIF>9T
/** Y3rt5\!
* @param page Ej"u1F14J
* The page to set. !YE zFU`L
*/ ue\t ,*KYd
publicvoid setPage(Page page){ `]<`$71w
this.page = page; Fe!9y2Mg
} i=rH7k
} .<YcSG
BJy;-(JP
+>tUz D
Fr [7
;gB`YNL
2. 编写业务逻辑接口,并实现它(UserManager, BC7 7<R!E)
\Y5W!.(%w
UserManagerImpl) q-_' W,
java代码: GBQn_(b9I
/tj$luls5
;;#`#v
/*Created on 2005-7-15*/ _A'{la~k
package com.adt.service; {/ 2E*|W~I
N`$!p9r
import net.sf.hibernate.HibernateException; ~x]9SXD%
t'(1I|7
import org.flyware.util.page.Page; 4 b,N8
2?DRLF]
import com.adt.bo.Result; {vVTv SC
r:g9 Z_
/** +ts0^;QO2{
* @author Joa ue{xnjw>U
*/ Tv$sqVe9
publicinterface UserManager { sWqM?2g
-t-tn22
public Result listUser(Page page)throws [*4fwk^
=.Tv)/ea
HibernateException; fZ{[]dn[
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} `JURQ:l)3^
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r{K;|'d%h
(f#b7O-Wn
'EhBRU%
java代码: L%h/OD
>I'%!E;
i.y)mcB4
/*Created on 2005-7-15*/ .*5 Z"Q['G
package com.adt.service.impl; >)**khuP7
ELD!{bMT
import java.util.List; JAjku6
\".^K5Pm
import net.sf.hibernate.HibernateException; E>uVofhml
'Jj=RAV`
import org.flyware.util.page.Page; Q[u6|jRt
import org.flyware.util.page.PageUtil; 8P: spD0
F-
rQ3
import com.adt.bo.Result; AkBMwV
import com.adt.dao.UserDAO; Ng=ONh
import com.adt.exception.ObjectNotFoundException; @g-Tk
import com.adt.service.UserManager; MMQ;mw=^]
v ~)LO2y
/** h<l1U'Bn7
* @author Joa %,q.),F
*/ anN#5jt
publicclass UserManagerImpl implements UserManager { '%;\YD9
\}"m'(\c
private UserDAO userDAO; 0C$vS`s&
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c
/** l=m(mf?QBg
* @param userDAO The userDAO to set. lB;FUck9
*/ &^.57]
publicvoid setUserDAO(UserDAO userDAO){ z\!K<d"Xv
this.userDAO = userDAO; #"*e+.j[;
} L
3XB"A#
U5r}6D!)
/* (non-Javadoc) cj$6
* @see com.adt.service.UserManager#listUser ~mp0B9L%
1KE:[YQ1
(org.flyware.util.page.Page) H)(jh
*/ Ey`h1Y
public Result listUser(Page page)throws IDFFc&
pPro }@@
HibernateException, ObjectNotFoundException { ROb\Rxm
int totalRecords = userDAO.getUserCount(); NL"G2[e
if(totalRecords == 0) UQ?%|y*Kc
throw new ObjectNotFoundException Xrqx\X
A[N{
("userNotExist"); 6,b"
page = PageUtil.createPage(page, totalRecords); j<yiNHC
List users = userDAO.getUserByPage(page); P 7D!6q
returnnew Result(page, users); F7}-!
} _e<o7Y@_
^QXbJJ
} Dm0a.J v
n6Z|Q@F
`ldz`yu6++
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e@<?zS6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 /n,a?Ft^N)
6"
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询,接下来编写UserDAO的代码: 5<YzalNf
3. UserDAO 和 UserDAOImpl: V9%aBkf8w
java代码: ?&+9WJ<M
:!TIK1
FY3IUG
/*Created on 2005-7-15*/ qSU|=
package com.adt.dao; ?h8{xa5b
8{
c !).
import java.util.List; [:EvTY
]ZoPQUS?
import org.flyware.util.page.Page; 5TKJWO.
OS-f(qXd+
import net.sf.hibernate.HibernateException; 3`.P'Fh(k
4@3[
/** :D:DnVZ-[@
* @author Joa f>$``.O
*/ Wd,a?31|
publicinterface UserDAO extends BaseDAO { 2tQ`/!m>v$
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publicList getUserByName(String name)throws -7qIToO.
fz_nsVD
HibernateException;
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Q;/a F`
publicint getUserCount()throws HibernateException; KA s 1(oG
\3YO<E!t
publicList getUserByPage(Page page)throws (g!p>m!Z
UK[v6".^h
HibernateException; J5M+FwZq
[1G^/K"
} >!6JKL~=
NZLAk~R;0
cI0 ]}S
d9^E.8p$
30j|D3-
java代码: ?=Pd
,El!fgL
2\D8.nQr
/*Created on 2005-7-15*/ ;t#]2<d*
package com.adt.dao.impl; LJlZ^kh
~+F;q
vq
import java.util.List; ?9+@+q
rJyCw+N0
import org.flyware.util.page.Page; >h~IfZU1
"f.Z}AbP
import net.sf.hibernate.HibernateException; :3h{ A`u
import net.sf.hibernate.Query; uRV<?y%
Av J4\
import com.adt.dao.UserDAO; I3b"|%
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lbt
/** mB'3N;~
* @author Joa jdA
]2]
*/ sy* y\5yJ
public class UserDAOImpl extends BaseDAOHibernateImpl \K2*Q&>
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h!
implements UserDAO { Dh|w^Q
qQ[b VD\*
/* (non-Javadoc) 3Hi+Z}8
* @see com.adt.dao.UserDAO#getUserByName ],etZ%z&
>`RRP}u=u
(java.lang.String) Ut@RGg+f8
*/ >H][.@LyR
publicList getUserByName(String name)throws \*T"M*;
4vnUN
HibernateException { I,@r5tKo
String querySentence = "FROM user in class F0Jx(
>TL^>D
com.adt.po.User WHERE user.name=:name"; b&)5:&MI
Query query = getSession().createQuery d50Vtm\
^Mkk@F&1
(querySentence); `TqSQg_l
query.setParameter("name", name); Qq& W3
return query.list(); w0m^ &,;#
} p&p.Q^"ok
gJN0!N'
/* (non-Javadoc) {^)70Vz>PE
* @see com.adt.dao.UserDAO#getUserCount() )KSoq/
*/ K+\nC)oG
publicint getUserCount()throws HibernateException { AEirj /
int count = 0; 3L>IX8_
String querySentence = "SELECT count(*) FROM '_s}o<
{Bvj"mL]j
user in class com.adt.po.User"; ,Z9>h[JF
Query query = getSession().createQuery iOw3MfO
gbBy/_b
(querySentence); W[bmzvJ_X
count = ((Integer)query.iterate().next !\ND(
V)M1YZV{
()).intValue(); 5X.ebd;PT
return count; % ~]xuP[
} %hS|68pN6
e'*HS7g
/* (non-Javadoc) Y
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* @see com.adt.dao.UserDAO#getUserByPage >B -q@D
AIl4]F5I
(org.flyware.util.page.Page) ~!iQ6N?PY
*/ B/f0P(7
publicList getUserByPage(Page page)throws \p&~,%
qZk'tRv
HibernateException { `|O yRU"EK
String querySentence = "FROM user in class P@}P k
0*%&>
com.adt.po.User"; t
!`Jse>
Query query = getSession().createQuery y7\"[<E`(V
Fqq6^um
(querySentence); nt1CTWKM8^
query.setFirstResult(page.getBeginIndex()) v9RW5
.setMaxResults(page.getEveryPage()); *V^ #ga#A
return query.list(); &[R8Q|1j
} 8^^[XbH
/c#`5L[
} V ~MiO.B
rZ1Hf11C
!c W[G/W8
k_|^ kdWJ
-cF'2Sfr
至此,一个完整的分页程序完成。前台的只需要调用 ~,6b_W p/
u0)7i.!M
userManager.listUser(page)即可得到一个Page对象和结果集对象 p0p4Xh1e
'XOX@UH d
的综合体,而传入的参数page对象则可以由前台传入,如果用 8iQ[9
Cr/`keR
webwork,甚至可以直接在配置文件中指定。 EOKzzX7 S
Iry
下面给出一个webwork调用示例: 4NR@u\S
java代码: ?^#lWx q
/?-7Fg+,
6R UrF
/*Created on 2005-6-17*/ 34|a\b}
package com.adt.action.user; :,pSWfK H
4-Z()F
import java.util.List; ;$j7H&UNQj
#C*8X+._y
import org.apache.commons.logging.Log; !LM<:kf.|
import org.apache.commons.logging.LogFactory; .0HZNWRtb
import org.flyware.util.page.Page; ]uL+&(cr
Y$8JM
import com.adt.bo.Result; t%1 ^Li
import com.adt.service.UserService; O;Y:uHf
import com.opensymphony.xwork.Action; t=euE{c
pI[ZBoR~
/** \kamcA
* @author Joa )U<Y0bZA!
*/ )u ?' ;
publicclass ListUser implementsAction{ O%!5<8Xrb
u'A#%}3
privatestaticfinal Log logger = LogFactory.getLog 9a$56GnW1
kdx
y\
jA
(ListUser.class); 2
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ZUXr!v/R:1
private UserService userService; #%3rTU
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private Page page; C.MoKa3
C&\5'[*
privateList users; YA(@5CZ
$K~LM8_CKy
/* oT95^y\9
* (non-Javadoc) $3+PbYY
* m(OvD!
* @see com.opensymphony.xwork.Action#execute() r} _c
*/ >cmE
t
publicString execute()throwsException{ 9?T{}| ?
Result result = userService.listUser(page); ^D67y%
page = result.getPage(); BfTcI)
users = result.getContent(); /nx'Z0&+X
return SUCCESS; :7N3N
} 8
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4B+9z^oQ
/** CDy^UQb
* @return Returns the page. $WQq?1.9
*/ TB6m0qX(
public Page getPage(){ Mq%,lJA\
return page; `ejUs]SR
} \g)Xt?w0Wo
eBN)g^
/** 3+7^uR$/I4
* @return Returns the users. C"T1MTB
*/ J<n+\F-s
publicList getUsers(){ IputF<p
return users; v]:=K-1n
} }_.:+H!@
mZk0@C&:6
/** 1m<RwI3s
* @param page qUF'{K
* The page to set. eKZ%2|+j!7
*/ s'P( ,!f
publicvoid setPage(Page page){ bJr[I
this.page = page; [BbutGvj
} 1MkI0OZE
XhU@W}}
/** T".]m7!
* @param users 9$K;Raz%
* The users to set. ?0*8RK
*/ 9|'B9C
publicvoid setUsers(List users){ }71LLzG`/
this.users = users; r4_eTrC,
} ZsP2>%"
I XA>`D
/** ["<nq`~
* @param userService ~!6K]hB4
* The userService to set. JeH;v0
*/ t/i5,le
publicvoid setUserService(UserService userService){ C2e.2)y
this.userService = userService; %n0;[sD0A
} UnWW/]E
} a.F Al@Br
W\*-xf|"d
sE(HZR1
8Ad606
A!W0S
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, d?idTcgs
m"tOe?
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 zQy"m-Q
{kI#A?M
么只需要: f}%D"gz
java代码: JM$.O;y
-
nHFrG
=o,
R_P}~l
<?xml version="1.0"?> &Jc_Fc(M
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork -XoP ia2
ytEC
1.0//EN" "http://www.opensymphony.com/xwork/xwork- GDaN
^[:9fs
1.0.dtd"> PrF}a<:n:
D?jk$^p~m#
<xwork> s)A<=)w/e
p(SRjQt
<package name="user" extends="webwork- kW3E =pr
igf)Hb;5
interceptors"> Ha>*?`?yI
$Byj}^ ;1
<!-- The default interceptor stack name iSRpfU
qKS;x@
--> jPvDFT^d/
<default-interceptor-ref 0:Xxl76v4
n7aU<`U
name="myDefaultWebStack"/> pI+!92Z
!X>=l
<action name="listUser" ]T!
}XXK
#1'\.v
class="com.adt.action.user.ListUser"> a[bBT@f
<param YO)$M-]>%J
AT
Zhr.
H
name="page.everyPage">10</param> AZ |yX
<result
,"-Rf<q/
^^` Jcd/
name="success">/user/user_list.jsp</result> wJb#g0
</action> 2Tav;LKX
pVp:@0h
</package> 5`/@N{e
.@ C{3$,VG
</xwork> Rn%N&1
Ef
Ko>&)%))$X
f67NWFX
4o:hyh
R$kpiqK
=tTqN+4
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 ^(}585b
@*N)i?>
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。 ]Hj<IvG
$Kj&)&M
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %b.UPS@I
q}Z3?W
8{U-m0v
FxG7Pk+=
6Z?j AXGSq
我写的一个用于分页的类,用了泛型了,hoho Z!xVgM{
|xr%6 [Ff
java代码: n@C~ev@%S
_;A $C(
~Aad9yyi
package com.intokr.util; _STB$cZ
9&%fq)gS
import java.util.List; 6!iJ;1PeE
C8N{l:1f]
/** F,Xo|jjj
* 用于分页的类<br> u
D 5%E7
* 可以用于传递查询的结果也可以用于传送查询的参数<br> PHg48Y"Nd
* .N4
* @version 0.01 .UCt|> $
* @author cheng ER2GjZa\z
*/ O[17";P
public class Paginator<E> { s}&bJ"!Z
privateint count = 0; // 总记录数 RIM`omM
privateint p = 1; // 页编号 g o5]<4`r
privateint num = 20; // 每页的记录数 F-(dRSDNM
privateList<E> results = null; // 结果 T`/IO.2
c9' '
/** I0AJY
)R
* 结果总数 Uv_N x10
*/ PMs z`
publicint getCount(){ 4W4kwU6D
return count; q"KnLA(
} T@wcHg
-37a.
publicvoid setCount(int count){ a^qNJ?R!
this.count = count; Y-piL8Xc
} 6TWWlU^e
5/[H+O1;
/** u/b7Z`yX}
* 本结果所在的页码,从1开始 kID[#g'
* b/$km?R
* @return Returns the pageNo. :vx$vZb
*/ 6Q4X6U:WB
publicint getP(){ IJOvnZ("A
return p; rn@`yTw^
} uD_v!
X#xFFDzN
/** %sh>;^58P
* if(p<=0) p=1
r#PMy$7L
* _eSdnHWx
* @param p 87!C@XlK_
*/ U8#xgz@
publicvoid setP(int p){ :qhpL-ER
if(p <= 0) 4:3rc7_
1
p = 1; Z.L?1V8Q1
this.p = p; >$67 7
} >t,M
>!e<}84b
/** c97{Pu
* 每页记录数量 uaw~r2
*/ ?[TfpAtQ`
publicint getNum(){ dCYCHHHF
return num; Zt
-1h{7
} dBsX*}C
h[KvhbD3
/** 7T``-:`[
* if(num<1) num=1 cxeghy:;U
*/ 3:/'t{ ^B
publicvoid setNum(int num){ xVB;s.'!
if(num < 1) gC%G;-gm
num = 1; Agh`]XQ2
this.num = num; 4nfu6Dq
} h<<>3 A
#mR4fst
/** Mk<Vydds
* 获得总页数 lLq<xf
*/ .%BT,$1K
publicint getPageNum(){ #T K~eHi
return(count - 1) / num + 1; BC>=B@H0
} i=a-<A5x
2'jOP"G
/** wCs^J48=
* 获得本页的开始编号,为 (p-1)*num+1 Th[f9H%
*/ DF]9@{
publicint getStart(){ 5
*}R$
return(p - 1) * num + 1; &adI (s~
} d9*hBm
<>eOC9;VY
/** KT|RF
* @return Returns the results. mpC`Yk
*/ }uHrto3M
publicList<E> getResults(){ iF5'ygR-Z
return results; c:S] R"
} W+wA_s2&D
5V[oE\B
public void setResults(List<E> results){ ulT8lw='
this.results = results; WFR?fDtE
} ^VW
PdH/Fe
$w)~O<_U
public String toString(){ TlL^7f}
StringBuilder buff = new StringBuilder 'AGto'Yy;
bUV >^d
(); 8*SDiZ
buff.append("{"); _8fr6tO+
buff.append("count:").append(count); )C(>H93
buff.append(",p:").append(p); :Eh\NOc_O
buff.append(",nump:").append(num); HjvCujJ
buff.append(",results:").append mOpTzg@
CZnK8&VDY
(results); j hYToMq
buff.append("}"); .Ig+Dj{)
return buff.toString(); +h^jC9,m~{
} mE O\r|A
wS+V]`b
} <H3ezv1M
q/3ziVd7p
TlAR.cV