Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 A+Je?3/.
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 p(4Ek"
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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 b2F1^]p
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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 {Q K9pZB
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分页支持类: +W>tdxOh
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java代码: H-5f!>)
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package com.javaeye.common.util; QBoX3w=
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import java.util.List; OZObx
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publicclass PaginationSupport { U_B`SS
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publicfinalstaticint PAGESIZE = 30; Yic'p0<
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privateint pageSize = PAGESIZE; p-g@cwOu
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privateList items; 5o(=?dXm4
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privateint totalCount; \v9<L'NP)
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privateint[] indexes = newint[0]; KRcg
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privateint startIndex = 0; oU 8o;zk0
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public PaginationSupport(List items, int uqy~hY
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totalCount){ n_] OYG>U
setPageSize(PAGESIZE); ]Otl(\v(h
setTotalCount(totalCount); `Sj8<O}
setItems(items); @1[LD[<
setStartIndex(0); -3b0;L&4>x
} 0$49X
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public PaginationSupport(List items, int 0P53dF
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totalCount, int startIndex){ r>q`# ~
setPageSize(PAGESIZE); ln!KL'T]
setTotalCount(totalCount); *XzUqK
setItems(items); <~8W>Y\m
setStartIndex(startIndex); !*#=7^#
} Bp6Evi
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public PaginationSupport(List items, int 2W~2Hk=0+%
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totalCount, int pageSize, int startIndex){ /3Gv51'
setPageSize(pageSize); L_Ai/'
setTotalCount(totalCount); CILk
setItems(items); x[oYN9O
setStartIndex(startIndex); ;[zx'e?!
} 1X9sx&5H
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publicList getItems(){ q{JD]A :
return items; &
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} Hm^p^,}_x
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publicvoid setItems(List items){ ,zyrBO0 Eq
this.items = items; 0UB'6wRVo
} 1!NaOfP;@
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publicint getPageSize(){ p_(hM&>C
return pageSize; 2I4P":q
} =UP)b9*h
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publicvoid setPageSize(int pageSize){ -T(V6&'Qi
this.pageSize = pageSize; e)bqE^JP
} Qqaf\$X
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publicint getTotalCount(){ K^vMIo h
return totalCount; V)Xcn'h
} MdfkC6P
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publicvoid setTotalCount(int totalCount){ dk ?0r
if(totalCount > 0){ }R'oAE}$
this.totalCount = totalCount; 7I
int count = totalCount / MLb\:Ihy
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pageSize; A,/S/_Q=
if(totalCount % pageSize > 0) rYqvG
count++; O#|E7;
indexes = newint[count]; ;Os3
!
for(int i = 0; i < count; i++){ w{qYP
indexes = pageSize * !14z4]b
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} y%y#Pb|
}else{ 1$W!<:uh
this.totalCount = 0; ro{MDs
} Pg36'aTe%j
} M@3H]t?
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publicint[] getIndexes(){ 1 &<@(S<
return indexes; 5*r6#[S\
} T_dd7Ym'8
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publicvoid setIndexes(int[] indexes){ {m?x},
this.indexes = indexes; +A3H#'
} #Grm-W9E
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publicint getStartIndex(){ @:@rks&
return startIndex; Y(f-e,
} >A/=eW/q
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publicvoid setStartIndex(int startIndex){ /~[R
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if(totalCount <= 0) loJ0PY'}=
this.startIndex = 0; -G 'lyH
elseif(startIndex >= totalCount) 9vu8koL
this.startIndex = indexes URgF8?n
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[indexes.length - 1]; 96avgyc
elseif(startIndex < 0) | |=Duk
this.startIndex = 0; qu%s 7+
else{ 2'U9!.o
this.startIndex = indexes CmOb+:4@K
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[startIndex / pageSize]; 4o3GS8
} %-Z~f~<?
} U:9vjY
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publicint getNextIndex(){ D,/9rH
int nextIndex = getStartIndex() +
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pageSize; >``GDjcJ
if(nextIndex >= totalCount) ,0bM*qob
return getStartIndex(); ]r6bJ2
else
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return nextIndex; "_j7kYAl
} : 4WbDeR
r
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publicint getPreviousIndex(){ DG=Ap:sl*$
int previousIndex = getStartIndex() - o=QF>\\
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pageSize; Rjl __90
if(previousIndex < 0) 8A .7=C' z
return0; ~0|hobk
else F.D1;,x
return previousIndex; ".?{Y(~
} 59J9V3na
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} di2=P)3
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抽象业务类
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java代码: ^^l"brPa
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/** Els= :4
* Created on 2005-7-12 CJ
*/ GuvF
package com.javaeye.common.business; ZS]f+}0/}
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import java.io.Serializable; oH0F9*+W
import java.util.List; 98'XSL|
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import org.hibernate.Criteria; I>Fh*2
import org.hibernate.HibernateException; y|{?>3
import org.hibernate.Session; z %E!tB2o
import org.hibernate.criterion.DetachedCriteria; Z8 %\v(L
import org.hibernate.criterion.Projections; {NgY8wQB
import :~R
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org.springframework.orm.hibernate3.HibernateCallback; ~j#6 goKn
import hpV
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org.springframework.orm.hibernate3.support.HibernateDaoS J&65B./mD9
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upport; -Bv1}xf=6
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import com.javaeye.common.util.PaginationSupport; {<[tYZmj.
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public abstract class AbstractManager extends
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D s,"E#?
HibernateDaoSupport { R${4Q1
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privateboolean cacheQueries = false; x~Ly$A2p
}.V0SM6
privateString queryCacheRegion; ?mfWm{QTt
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publicvoid setCacheQueries(boolean ^^3va)1{!
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cacheQueries){ wDMB
this.cacheQueries = cacheQueries; r9a!,^}F
} {^5<{j3e
!2U7gVt"*
publicvoid setQueryCacheRegion(String NF(IF.8G
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queryCacheRegion){ ^npS==Y]!.
this.queryCacheRegion = To{G#QEgG
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queryCacheRegion; )F#<)Evw
} xgqv2s>L
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publicvoid save(finalObject entity){ ?$@KwA
getHibernateTemplate().save(entity); eTRx 6Fri(
} 6O@ ^`T
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publicvoid persist(finalObject entity){ ecqz@*d&
getHibernateTemplate().save(entity); QDgEJ%U-
} |od4kt
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publicvoid update(finalObject entity){ kPX2e h
getHibernateTemplate().update(entity); LVFsd6:h
} dIfs8%kl
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publicvoid delete(finalObject entity){ CBnouKc:
getHibernateTemplate().delete(entity); r|\'9"@
} CNRU"I+jU
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publicObject load(finalClass entity, PVS<QN%
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finalSerializable id){ ^Im%D(MY
return getHibernateTemplate().load Q#ZD&RZ9.
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(entity, id); ['OCw {<
} bu"68A;>
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publicObject get(finalClass entity, 7=p-A_X
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finalSerializable id){ Neo^C_[vN
return getHibernateTemplate().get
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(entity, id); q~Q)'*m
} VM]GYz|#]
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publicList findAll(finalClass entity){ ueE?"Hk
return getHibernateTemplate().find("from dp[w?AMhM9
{r].SrW9s9
" + entity.getName()); Mi/ &$"=
} csdOIF
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publicList findByNamedQuery(finalString s*)41\V0
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namedQuery){ CmJ?_>
return getHibernateTemplate ;la#Vf:]
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().findByNamedQuery(namedQuery); 8R)D ! 7[l
} sR>`QIi(a
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publicList findByNamedQuery(finalString query, WBw
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finalObject parameter){ 'Wf?elB+
return getHibernateTemplate K{zCp6
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().findByNamedQuery(query, parameter); Tbi]oB#
} iBKb/Oi6
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publicList findByNamedQuery(finalString query, SvX=isu!.
OB I+<2`Oc
finalObject[] parameters){ `\/toddUh[
return getHibernateTemplate 43J\8WBn@
@ kJ0K
().findByNamedQuery(query, parameters); 7>'uj7r]=
} o9m
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publicList find(finalString query){ SLJ&{`"7
return getHibernateTemplate().find z29qARiX
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(query); 4-7kS85
} yHWi[7$
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publicList find(finalString query, finalObject 2gd<8a' '
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parameter){ E\]OySC%C$
return getHibernateTemplate().find SUH mBo"}
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(query, parameter); {J,6iP{>ZN
} s;fVnaqG:
.
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public PaginationSupport findPageByCriteria )\T@W
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(final DetachedCriteria detachedCriteria){ XJx,9trH
return findPageByCriteria 6X@mPj[/
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); r-RCe3%g%
} AIZW@ Nq.5
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public PaginationSupport findPageByCriteria kCima/+_
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(final DetachedCriteria detachedCriteria, finalint 7"ylN"syZ
p+, 1Fi
startIndex){ 2.[_t/T
return findPageByCriteria hc-lzYS
#*!+b
(detachedCriteria, PaginationSupport.PAGESIZE, mD9STuA$H
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startIndex); ;yF[2P ;
} 6(>3P
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public PaginationSupport findPageByCriteria a
@6^8B?w;
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(final DetachedCriteria detachedCriteria, finalint [NYj.#,oR
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pageSize, wA?@v|,dZ
finalint startIndex){ 8@E8!w&~
return(PaginationSupport) `5~7IPl3
rmOQ{2}
getHibernateTemplate().execute(new HibernateCallback(){ !G7h9CF|{
publicObject doInHibernate Vy]A,Rn7
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(Session session)throws HibernateException { Rr%tbt.sE
Criteria criteria = |y.zocBj
@u,+F0Yd
detachedCriteria.getExecutableCriteria(session); S[vRw]*
int totalCount = (nGkZ}p
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((Integer) criteria.setProjection(Projections.rowCount XJe/tR
_-n Y2)
()).uniqueResult()).intValue(); #C4|@7w%
criteria.setProjection {={^6@
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(null); +9RJ%i&Ec
List items = ~%`EeJwT
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criteria.setFirstResult(startIndex).setMaxResults 8=:A/47=J
`%|u!
(pageSize).list(); XTV0Le\f
PaginationSupport ps = ;v_ls)_,-
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new PaginationSupport(items, totalCount, pageSize, g^jJ8k,7(
J==}QEhQ{
startIndex); D}MoNE[r
return ps; Yt{ji
} ~P/]:=
}, true); {ih:FcI
} F=srkw:*.
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public List findAllByCriteria(final D ZVXz|g
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DetachedCriteria detachedCriteria){ gt/!~f0r
return(List) getHibernateTemplate SZ/(\kQ6
mH)OB?+lq
().execute(new HibernateCallback(){ q3+I<qsAz
publicObject doInHibernate ^p,3)$
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(Session session)throws HibernateException { [m\,+lG?)j
Criteria criteria = /_q#ah
;u,rtEMy;
detachedCriteria.getExecutableCriteria(session); G]-%AO{K
return criteria.list(); 4`s)ue
} .U 39nd
}, true); Atd1qJ
} uJY.5w
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public int getCountByCriteria(final [t{](-
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DetachedCriteria detachedCriteria){ /ERNS/w
Integer count = (Integer) =U NT.]
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getHibernateTemplate().execute(new HibernateCallback(){ j7}lF?cJ2
publicObject doInHibernate T`?n,'!(
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(Session session)throws HibernateException { cz#_<8'N
Criteria criteria = $@2"{9Z
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detachedCriteria.getExecutableCriteria(session); 4\ FP
return )|RZa|`-G
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criteria.setProjection(Projections.rowCount :_Fxy5}
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()).uniqueResult(); Fc'[+L--Q
} VjB*{,
}, true); /PqUXF
return count.intValue(); (@q3^)I4
} >S'>!w
} +_~,86
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用户在web层构造查询条件detachedCriteria,和可选的 mgVML&^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ln#\sA?iG
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PaginationSupport的实例ps。 [4>r6Hqxr
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ps.getItems()得到已分页好的结果集 3ji:O T
ps.getIndexes()得到分页索引的数组 QKccrAo
ps.getTotalCount()得到总结果数 y(v_-6b
ps.getStartIndex()当前分页索引 Cs4hgb|
ps.getNextIndex()下一页索引 oLS7`+b$
ps.getPreviousIndex()上一页索引 <d"Gg/@a
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =}R~0|^
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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 5UOk)rOf
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一下代码重构了。 9m8ee&,
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我把原本我的做法也提供出来供大家讨论吧: Y<Q\d[3^F
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首先,为了实现分页查询,我封装了一个Page类: h8=h >W-
java代码: UX_I6_&
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/*Created on 2005-4-14*/ O2 v.
package org.flyware.util.page; <HQ&-j x
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/** u+2Lm*M
* @author Joa <xlm
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* V;93).-$
*/ tcA;#^jc
publicclass Page { D{C:d\ e)$
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/** imply if the page has previous page */ lIh[|]
privateboolean hasPrePage; ~G`J
r
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/** imply if the page has next page */ e<5Y94YE
privateboolean hasNextPage; o.^y1mH'
SRCOs1(EK9
/** the number of every page */ Jqru AW<
privateint everyPage; `^##b6jH
JD~a UB%
/** the total page number */ nbxR"UH
privateint totalPage; %MJ;Q?KB
2jA%[L9d^
/** the number of current page */ Y {c5
privateint currentPage; s, XM9h>P4
|(ocDmd
/** the begin index of the records by the current U CY2]E
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query */ 6vp0*ww
privateint beginIndex; x~/+RF XF
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/** The default constructor */ >n!ni(
public Page(){ j|K.i/
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} @J vZ[T/
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/** construct the page by everyPage D;js.ZF
* @param everyPage N[k<@Q?*a
* */ |F!F{d^p
public Page(int everyPage){ d^84jf.U
this.everyPage = everyPage; `="v>qN2\
} i2`0|8mw'
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/** The whole constructor */ o^ h(#%O
public Page(boolean hasPrePage, boolean hasNextPage, ]d'^Xs
qY(:8yC36
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int everyPage, int totalPage, Z+idLbIs
int currentPage, int beginIndex){ #Lka+l;L7
this.hasPrePage = hasPrePage; XDLEVSly7
this.hasNextPage = hasNextPage; 40K2uT{cq
this.everyPage = everyPage; 8$}OS-
this.totalPage = totalPage; PZM42"[&
this.currentPage = currentPage; ^7u#30,}3~
this.beginIndex = beginIndex; $TG?4
} \&q=@rJp(z
4}yE+dRUK:
/** 9
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* @return ]\;xN~l
* Returns the beginIndex. OE"<!oIs
*/ v>-YuS
publicint getBeginIndex(){ agsISu(
return beginIndex; 3Gd0E;3sk~
} '29WscU
oR %agvc^^
/** y\[r(4h
* @param beginIndex NWKi
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* The beginIndex to set. {ZqQ!!b
*/ W_<4WG
publicvoid setBeginIndex(int beginIndex){ 9<cOYY
this.beginIndex = beginIndex; uO'/|[`8
} E`AYee%l
e@jfIF0=}
/** <abKiXA"
* @return -:]@HD :
* Returns the currentPage. l{%a&/
*/ $G[KT):N
publicint getCurrentPage(){ {;k_!v{
return currentPage; 7~vqf3ON4J
} kwar}:`
3j*'HST
/** fNoR\5}!
* @param currentPage \A(5;ZnuD
* The currentPage to set. !F7: i
*/ n,nisS
publicvoid setCurrentPage(int currentPage){ RvW.@#EH0
this.currentPage = currentPage; >L[lV_M_>
} zilaP)5x6
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/** \"d?=uFe
* @return J
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* Returns the everyPage. Z[}
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*/ (~#G'Hd
publicint getEveryPage(){ 2
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return everyPage; E1W:hGI
} ]^@0+!
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/** :]c=pH
* @param everyPage >&hX&,hG
* The everyPage to set. ;$;rD0i|
*/
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publicvoid setEveryPage(int everyPage){ QS\
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this.everyPage = everyPage; l0`'5>
} lzfDH=&
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/** F=i!d,S
* @return Yy@g9mi
* Returns the hasNextPage. /=ylQn3
*
*/ [TCRB`nTQF
publicboolean getHasNextPage(){ 1+^n!$
return hasNextPage; v3^t/[e~:
} k4R4YI"jV
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/** q6&67u0
* @param hasNextPage -f.R#J$2
* The hasNextPage to set. k7T
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*/ DV,DB\P$
publicvoid setHasNextPage(boolean hasNextPage){ /"MJkM.~E
this.hasNextPage = hasNextPage; rfTe
} xjrlc9
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/** hbnS~sva
* @return xBWx+My
* Returns the hasPrePage. BWEv1' v
*/ ysVi3eq
publicboolean getHasPrePage(){ 7jT}{
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return hasPrePage; f0FP9t3k
} ohplj`X[21
4\1;A`2%0
/** 4NUNOv`[{
* @param hasPrePage P;c0L;/
* The hasPrePage to set. f".q9{+p,
*/ _BwKY#09Zp
publicvoid setHasPrePage(boolean hasPrePage){ UoRDeYQ`E
this.hasPrePage = hasPrePage;
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} wA",SBGX
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/** :rL?1"
* @return Returns the totalPage. fz8h]PZ
* 5Hy3\_ +
*/ Y?t2,cm
publicint getTotalPage(){ b[0S=e
G
return totalPage; yM|g|;U
} Gl;f#}
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/** cD8Ea(
* @param totalPage x~Cz?ljbn
* The totalPage to set. DO%Pwfkd
*/
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publicvoid setTotalPage(int totalPage){ .FJj
this.totalPage = totalPage; K=o:V&
} .5z&CJDiIi
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:
} yDuq6`R*
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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 94YA2_f;
&L'6KEahR
个PageUtil,负责对Page对象进行构造:
d.I%k1`(
java代码: kz_M;h>
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/*Created on 2005-4-14*/ a_AJ)4
package org.flyware.util.page; lfRH`u
V:8@)Hc=
import org.apache.commons.logging.Log; ExqM1&zpK
import org.apache.commons.logging.LogFactory; GqMB^Ad
k|5k8CRX
/** |
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* @author Joa iAgOnk[
* ,A?{~?u.
*/ tStJ2-5*t
publicclass PageUtil { N:7.:Yw
k1m'Ka-
privatestaticfinal Log logger = LogFactory.getLog n@_)fFD%
Z) t{JHm:
(PageUtil.class); e]Puv)S>{8
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/** f:&)"
* Use the origin page to create a new page sX
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* @param page Z"]xdOre
* @param totalRecords *iYMX[$
* @return C&e8a9*,(a
*/ >I|<^$/
publicstatic Page createPage(Page page, int @??u})^EL
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totalRecords){ AT-0}9z{
return createPage(page.getEveryPage(), j+ I*Xw
ZDfS0]0F
page.getCurrentPage(), totalRecords); >6w@{p2B
} !*9FKDB{
y&h~Oa?,;
/** +<z7ds{Z
* the basic page utils not including exception b13nE.
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VN
handler 8cB=}XgYS
* @param everyPage UYH|?Jw!N
* @param currentPage PMQb\%iE"
* @param totalRecords }=TqJy1
* @return page $G)&J2zL
*/ \Ec
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publicstatic Page createPage(int everyPage, int [@x
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currentPage, int totalRecords){ ?~{rf:Y
everyPage = getEveryPage(everyPage); QP'qG@j[:
currentPage = getCurrentPage(currentPage); xiEcEz'lk
int beginIndex = getBeginIndex(everyPage, nM=2"`@$
LMt0'Ml9
currentPage); S3nB:$_-;
int totalPage = getTotalPage(everyPage, ykJ+%gla
<. ezw4ju
totalRecords); makaI0M
boolean hasNextPage = hasNextPage(currentPage, 87R%ke
C-_(13S
totalPage); Sb^a dd0dT
boolean hasPrePage = hasPrePage(currentPage);
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returnnew Page(hasPrePage, hasNextPage, Q=^ktKMeR
everyPage, totalPage, ux%&lff
currentPage, SlR7h$r'
{_rZRyr
beginIndex); O}e|P~W
} KsZ@kTs
r4;^c}
privatestaticint getEveryPage(int everyPage){ ?0? x+
return everyPage == 0 ? 10 : everyPage; F@B
} ;O Q#@|D
4F}g(
privatestaticint getCurrentPage(int currentPage){ 8}Fw%;Cb
return currentPage == 0 ? 1 : currentPage; !IfI-Q
} 0TpBSyx.
?T tQZ
privatestaticint getBeginIndex(int everyPage, int Iq^~
Q@PJ)fwN
currentPage){ xhw8#
return(currentPage - 1) * everyPage; 0*/mc9 6
} + 8MW$ m$
XYz,NpK
privatestaticint getTotalPage(int everyPage, int d/"gq}NT
xC=
y^-
1
totalRecords){ aS c#&{
int totalPage = 0; n$XMsl.>
rhlW
if(totalRecords % everyPage == 0) Z'7 c^c7_
totalPage = totalRecords / everyPage; dt`9RB$
else c#]'#+aH
totalPage = totalRecords / everyPage + 1 ; O|A~dj`
Y\ #.EVz
return totalPage; n's2/9x
} Z"teZ0H
}CB=c]p
privatestaticboolean hasPrePage(int currentPage){ QO1A976o
return currentPage == 1 ? false : true; Dme(Knly
} WZ-4^WM=!
>
gA %MT
privatestaticboolean hasNextPage(int currentPage, S!`4Bl
]# tGT0
int totalPage){ 8:3oH!n
return currentPage == totalPage || totalPage == @&nx;K6h
.FfwY 'V
0 ? false : true; d/ 'A\"o+
} ae9k[=-
-s?dzX
N}.Q%&6:
} T U"K#V&u
>oM9~7f
;-Y]X(z>
!`O_VV`/@
ihpz}g
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。 0-;DN:>
O+{pF.P#V
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 ($[r>)TG
+O.&64(
做法如下: } K+Q9<~u
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 S<2CG)K[
1pYmtr
的信息,和一个结果集List: o2 T/IJP
java代码: bJG!)3cx
B
$ y44
,oB k>
/*Created on 2005-6-13*/ :*F3
package com.adt.bo; ~u~[E
"c !oOaA
import java.util.List; %z!d4J75
WacU@L $A
import org.flyware.util.page.Page; LS2ek*FJO
\@
WsF$
/** $Z(g=nS>
* @author Joa x|,aV=$o
*/ r[UyI3(i^
publicclass Result { (to/9OrG
Z CQt1;
private Page page; 3 -_U-:2"
`DWi4y7
private List content; O0=,&=i
-!bLMLIg
/** sBuq
* The default constructor Jegx[*O>b
*/ Ls$g-k%c@Q
public Result(){ ]\os`At
super(); Vgru, '
} ==e#CSJq
upEPv
.h
/** xP5mL3j
* The constructor using fields }G,SqpcG
* NbdMec
* @param page ^*?B)D =,
* @param content /F8\%l+
*/ dx?njR
public Result(Page page, List content){ D?*sdm9r`
this.page = page; Z,8+@
this.content = content; $jm>tW&;
} (&Tb,H)=
d'x<F[`O
/** utm+\/
* @return Returns the content. !+|N<`
*/ G(|(y=ck
publicList getContent(){ +N(YR3
return content; RwE*0 T
} 1R+ )T'in
meM.?kk(
/** }r<@o3t
* @return Returns the page. {,-5k.P[
*/ x}8T[
public Page getPage(){ nGJIjo_I
return page; =Q=&Ucf_
} }Cq9{0by?a
W|-N>,G
/** W1vAK
* @param content p`l[cVQ<
* The content to set. d`],l\oC
*/ J%O4IcE
public void setContent(List content){ LN3dp?;_{
this.content = content; 3RH#e1Y
}
!K^Z5A_;
7s fuju(
/** L};;o+5uJD
* @param page 4-nr_
WCm4
* The page to set. 5vh"PlK`s
*/ eze(>0\f
publicvoid setPage(Page page){ D@b<}J>0'
this.page = page; t ]I(98pY
} s3E~X
} pv?17(w(\
`@.s!L(V
V8U`%/`N
;R|#ae@
@Jn:!8U0
2. 编写业务逻辑接口,并实现它(UserManager, 3ws(uF9$
qL;T&h
UserManagerImpl) }v$=mLy
java代码: n\ ',F
zQj%ds:
JQh s=Xg
/*Created on 2005-7-15*/ m<'xlF
package com.adt.service; $}nUK~$GSv
Rd1ku=
import net.sf.hibernate.HibernateException; %d#)({N
e%v4,8
import org.flyware.util.page.Page; L9YwOSb.
v7OV;ea$
import com.adt.bo.Result; \NQ)Po@z
2:5gMt
/** +=H>s;B
* @author Joa ^Er`{|o6u
*/ A%w]~ chC9
publicinterface UserManager { lnC Wu@{
<VxpMF
public Result listUser(Page page)throws FR6I+@ oX~
g*c\'~f;
HibernateException; F#bo4'&>@
DMxS-hl
} +2fJ
)?IA`7X
pD6g+Taj
jhbH6=f4]^
95 .'t}
java代码:
Vh2/Ls5
N u2]~W&
/Vd#q)b%T
/*Created on 2005-7-15*/ Fx:en|g
package com.adt.service.impl; ~_j%nJ
&2
v4##(~Tu
import java.util.List;
nK'8Mo
n@,eZ!
import net.sf.hibernate.HibernateException; <07W&`Dw
M-K@n$k
import org.flyware.util.page.Page; 3N*C]
import org.flyware.util.page.PageUtil; [,$mpJCI
7Z~szD
import com.adt.bo.Result; $,zM99
import com.adt.dao.UserDAO; X6*y/KGN
import com.adt.exception.ObjectNotFoundException; .-~%w
import com.adt.service.UserManager; uvv-lAbjw
UVmyOC[Y{
/** )hJjVitG
* @author Joa [K@!JY
*/ L=wFo^N
publicclass UserManagerImpl implements UserManager { !3Z|!JY
>37}JUG
private UserDAO userDAO; lbU+a$
iwjl--)@K
/** +pViHOJu&V
* @param userDAO The userDAO to set. I"<.
h'
*/ U105u.#7
publicvoid setUserDAO(UserDAO userDAO){ $hp?5KM
this.userDAO = userDAO; by<@Zwtf
} HtYR 0J
\0T*msYQ
/* (non-Javadoc) Wc;D{p?Lb
* @see com.adt.service.UserManager#listUser #&KE_n
&0Zk3D4
(org.flyware.util.page.Page) KBHKcFk
*/ $v@$oPmMj
public Result listUser(Page page)throws 7#.PMyK9
D c.W vUM
HibernateException, ObjectNotFoundException { `3P62M<
int totalRecords = userDAO.getUserCount(); f8jz49C
if(totalRecords == 0) QjN3j*@
throw new ObjectNotFoundException 6Q.whV%y
J,KTc'[
("userNotExist"); G/44gKl
page = PageUtil.createPage(page, totalRecords); Riuv@i^6K
List users = userDAO.getUserByPage(page); ,5uDEXpt{
returnnew Result(page, users); @_ZWP
} ?Cfp=85ea!
'z!#E!i
} !-nm7Q
Dohe(\C@
i j;'4GzQL
MtTHKp
`9{C/qB
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Eakjsk
&?sjeC_
询,接下来编写UserDAO的代码: HTpd~W/\
3. UserDAO 和 UserDAOImpl: }mZ*f y0t
java代码: e;r-}U
c}s3c
>`d
ui0(#2'h%
/*Created on 2005-7-15*/ ,
)3+hnFY
package com.adt.dao; vz5RS
xmd$Jol^
import java.util.List; 5z]KkPQ
)X$n'E
import org.flyware.util.page.Page; ` &7?+s
qZ1PC>
import net.sf.hibernate.HibernateException; Q_Squuk
:u93yH6~8
/** c4W"CD;D
* @author Joa PP|xIAc
*/ >m{-&1Tx
publicinterface UserDAO extends BaseDAO { :8T@96]P
'-TFr NO;h
publicList getUserByName(String name)throws S]@iS[|?
{'aqOlw3<j
HibernateException; c{ (%+
3_-m>J**
publicint getUserCount()throws HibernateException; WTN!2b
MRu+:Y=K
publicList getUserByPage(Page page)throws D)6|| z}
y%Ah"UY
HibernateException; 1&nrZG9
`&JA7UD>
} Ia"
Mi+{
ueo3i1
#R|4(HlL
Y:BrAa[
40/[uW"
java代码: Yb/^Qk59
[C\?}.+v
c~;.m<yrf
/*Created on 2005-7-15*/ Hb4rpAeP
package com.adt.dao.impl; <!$Cvx\U
q\Z1-sl~s
import java.util.List; gRSG[GMV
"$9ZkADO
import org.flyware.util.page.Page; i?9Lf
NYRNop( N#
import net.sf.hibernate.HibernateException; $%t
import net.sf.hibernate.Query; 0Z(b/fdS
5J3kQ;5Q?
import com.adt.dao.UserDAO; tJ3s#q6
qpCi61lTDJ
/**
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* @author Joa #y%Ao\~kG
*/ ,oe4*b}O=.
public class UserDAOImpl extends BaseDAOHibernateImpl IC~D?c0H:
$E6uA}s
implements UserDAO { YSmz)YfX9
h~t]WN
/* (non-Javadoc) Sj+#yct -
* @see com.adt.dao.UserDAO#getUserByName @,.H)\a4
~46ed3eGzi
(java.lang.String) B$j,: ^
*/ iqYc&}k,
publicList getUserByName(String name)throws e{/\znBS%
7ac3N
HibernateException { !s:|Ddv
String querySentence = "FROM user in class ,"v%
}_x oT9HUr
com.adt.po.User WHERE user.name=:name"; NeP1 #
Query query = getSession().createQuery g!UM8I-$
dl4.jLY
(querySentence); -TWo-iu^
query.setParameter("name", name); !)]3@$#
return query.list(); |@nXlZE
} @VAhmYz
|v&&%>A2
/* (non-Javadoc) `P~RG.HO
* @see com.adt.dao.UserDAO#getUserCount() dewu@
*/ w,7
GC5j\
publicint getUserCount()throws HibernateException { + h&V;
int count = 0; {iv=KF_S_
String querySentence = "SELECT count(*) FROM M
5h U.3.L
K||85l?<
user in class com.adt.po.User"; t30V_`eQ
Query query = getSession().createQuery 60Z)AQs;+J
F=H=[pSe
(querySentence); rX[R`,`>Z[
count = ((Integer)query.iterate().next \<%a`IA!*
*V/SI E*8
()).intValue(); !p2&$s"N.
return count; |bh:x{h
} \wd~Y
%lxo?s@GE
/* (non-Javadoc) \BDNF<_
* @see com.adt.dao.UserDAO#getUserByPage E =E
jZGmTtx
(org.flyware.util.page.Page) 2iu;7/
*/ (|-/S0AV
publicList getUserByPage(Page page)throws +^.(3Aw
0=04:.%D
HibernateException { Kh> ^;`h
String querySentence = "FROM user in class %`~8j H@
:;EzvRy
com.adt.po.User"; _Z%C{~,7)x
Query query = getSession().createQuery l"Css~^
*\>7@r[%5
(querySentence); Msf yIB
query.setFirstResult(page.getBeginIndex()) R]dB Uu
.setMaxResults(page.getEveryPage()); #q-t!C%E
return query.list(); ~_q\?pw<$L
} k$zDofdfp
@"6BvGU2s
} @!-= :<h
5VI'hxU4Qg
"371`!%
r8qee$^M
i9\Pks#l%
至此,一个完整的分页程序完成。前台的只需要调用 Z7(hW,60
49CMRO,T
userManager.listUser(page)即可得到一个Page对象和结果集对象 =(o$1v/k
vUW !
的综合体,而传入的参数page对象则可以由前台传入,如果用 <J- aq;p
(GZm+?
webwork,甚至可以直接在配置文件中指定。 7>.^GD
2oNlQiE_
下面给出一个webwork调用示例: ZnQnv@{8l
java代码: \"5 \hX~dS
C'{Z?M>
"k+QDQ3=
/*Created on 2005-6-17*/ %K zURv
package com.adt.action.user; )/BKN` ,
%j=7e@
import java.util.List; ALFw[1X
Z*JZUbo-Q
import org.apache.commons.logging.Log; *d@}'De{8
import org.apache.commons.logging.LogFactory; W?.Y%wc0
import org.flyware.util.page.Page; >
vgqf>)kk
7n#0eska,
import com.adt.bo.Result; )sW1a
import com.adt.service.UserService; }!2|*Y
import com.opensymphony.xwork.Action;
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p.zU9rID
/** ieObo foD
* @author Joa KxY|:-"Tt
*/ ,O2Uj3"
publicclass ListUser implementsAction{ nwz}&nR
;]p#PNQ0
privatestaticfinal Log logger = LogFactory.getLog 5t0$nKah]
7bTs+C_;7
(ListUser.class); pxP7yJL`
ZV&=B%J bs
private UserService userService; ?Hq`*I?b9
@mW0EJ8bb
private Page page; H>M0GL
Uq"RyvkpP
privateList users; ]Qj65]
4H{L>e
/* x*(pr5k
* (non-Javadoc) #B54p@.}
* t0?\5q
* @see com.opensymphony.xwork.Action#execute() -OoXb( I4
*/ eqXW|,zUm
publicString execute()throwsException{ j'~xe3j
Result result = userService.listUser(page); No j6Ina
page = result.getPage(); l'c|I
&Y]
users = result.getContent(); TMGZHOAt
return SUCCESS; U%2 pbGU
} ,VbP$1t
-Ndd6O[ a5
/** O(CUwk
* @return Returns the page. F7a\Luae
*/ QRx'BY$5
public Page getPage(){ {n{
j*+
return page; m/CA
} GT`:3L
4uD!-1LT@
/** i $#bg^
* @return Returns the users. lZ'NLbK
*/ H2[S]`?
publicList getUsers(){ X`[or:cB
return users; q^k6.5*"
} cy%^P^M
.z)E
/** !y `wAm>n
* @param page BPtU]Bv-
* The page to set. ;IE|XR(
*/ L~CwL
publicvoid setPage(Page page){ DCFYpkR%
this.page = page; KGFmC[
} t d-EB&i\
k oZqoP
/** Qgf\gTF$r+
* @param users S"V|BU
* The users to set. ig)rK<@*[
*/ mi6<;N2w|
publicvoid setUsers(List users){ ney6N@
this.users = users; <Hig,(=`.
} WR%x4\,d#
=; `+^
/** Ks7DoXCvE
* @param userService VYMs`d[
* The userService to set. ~;9B\fE`
*/ Tz:mj
publicvoid setUserService(UserService userService){ xOp8[6Ga'
this.userService = userService; wk'|gI[W
} Vd1.g{yPV
} P0Z1cN}
#0zMPh /U}
c>,|[zP{
E}00y%@*J
%nSLe~b
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, 7?Q<kB=f
2aNCcZw0
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 049E#[<Q"
]SA]{id+
么只需要: g/'CX}g`
java代码: YQ:FBj
CuR.a
]_G!(`Udh
<?xml version="1.0"?> Lp`q[Z*
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Tky\W%Ag
-U`]/
1.0//EN" "http://www.opensymphony.com/xwork/xwork- gf$5pp-
07:CcT
1.0.dtd"> w)2X0ev"
H.3+5po
<xwork> :<=A1>&8
ZaIlo5
<package name="user" extends="webwork- HTA@en[5
G|*^W;(Z
interceptors"> f5.rzrU
^rO3B?_
<!-- The default interceptor stack name Vv8e"S
6p|*H?|It
--> @)owj^sA
<default-interceptor-ref |j3mI\ANF
(U#4j 6Q
name="myDefaultWebStack"/> sN]O]qYXJ
Lf`LFPKb
<action name="listUser" (qG |.a
jODx&dVr
class="com.adt.action.user.ListUser"> x%Ivd
<param A2LqBirkl
8VxjC1v+
name="page.everyPage">10</param> wH&[Tg
<result J\VG/)E
Vj(}'h-c\
name="success">/user/user_list.jsp</result> t6V@00M@
</action> sq1Z;l31"
zX*+J"x
</package> -b'93_ZTu:
Z\Qa6f!
</xwork> 6P@3UQ)}s
UlF=,0P
CvDy;'{y1
?|Y/&/;%I
Huzw>
YbjeM6#E
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 0k Ezi
OJ0Dw*K<
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 WPLM*]6
2@ 4^ 81
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 aM/sD=}
G4DuqN~2m
"uK`!{
X$z@ *3=
wa/
:JE
我写的一个用于分页的类,用了泛型了,hoho U6SgV
8
3N%%69JN)
java代码: ,2hZtJ<A
:{2exu
(KQAKEhD!
package com.intokr.util; <tp\+v!u
N#<h/
import java.util.List; _h;#\ )%~
P5{|U"Y_
/** {p#[.E8
* 用于分页的类<br> }ti+tM*
* 可以用于传递查询的结果也可以用于传送查询的参数<br> DxX333vC
* 1~X~"M
* @version 0.01 >9KQWeD
* @author cheng PP{2{
*/ @mM])V
public class Paginator<E> { zQsu~8PX
privateint count = 0; // 总记录数 V *2=S
privateint p = 1; // 页编号 WPbWG$Li
privateint num = 20; // 每页的记录数 9AJMm1_
privateList<E> results = null; // 结果 P\#z[TuHKC
<3]Qrjl
,b
/** ;Kb]v\C:
* 结果总数 =l%"Om*A
*/ 9n][#I)a3
publicint getCount(){ 4.@gV/U(|
return count; C/nzlp~
} n|,kL!++.
3PS(1
publicvoid setCount(int count){ 9r@T"$V#c
this.count = count; X8U._/'N
} _VIVZ2mU=
Q=hf,/N
/** ,XmTKOc
* 本结果所在的页码,从1开始 mRIW9V
* O/;$0`~hY
* @return Returns the pageNo. MguH)r`uT
*/ /W !A^
publicint getP(){ gB\
a
return p; F[ca4_lK
} m*VM1k V
u#tLY/KA
/** ?cQ
* if(p<=0) p=1 ,~@0IKIA
Q
* J(&a,w>p
* @param p pq;)l(Hi
*/ !?Tu pi
publicvoid setP(int p){ HRF4
R o
if(p <= 0) ebF},Q(48
p = 1; ^FLuhLS\*
this.p = p; aOYRenqu
} oL' :07_
=Mc]FCV
/** m4:b?[
* 每页记录数量 .^s%Nh2jM
*/ 22?9KZ`Z=
publicint getNum(){ N"~P` H![x
return num; 54 8w
v
} +M9=KVr
X/,4hjg
/** ~g2ColFhu
* if(num<1) num=1 >M7e'}0;
*/ `m5cU*@D
publicvoid setNum(int num){ 9\W~5J<7
if(num < 1) !:3NPjhf1Y
num = 1; e=nEx Y
this.num = num; z41
p$
} O2{_:B>K[
bHcb.;<
/** :xd&V%u`
* 获得总页数 ?Mp)F2'
*/ Fs:l"5~>1
publicint getPageNum(){ WU1I>i
return(count - 1) / num + 1; ~S Js2-2
} 1 'EMYQ
{m}B=u
/** Dbr(Wg
* 获得本页的开始编号,为 (p-1)*num+1 <wTkPErUG
*/ 9;;1 "^4/
publicint getStart(){ *>.~f<V
return(p - 1) * num + 1; `xbk)oW#
} 6m21Y8N
?7:"D e
/** f9u["e
* @return Returns the results. >fo &H_a
*/ ox {Cm
publicList<E> getResults(){ ~I/7{B|yX
return results; kYs2AzS{d
} T$%u=$E%F
,%dn)gt7
public void setResults(List<E> results){ I_xJ[ALdm
this.results = results; *cTN5S>
} `(.ue8T
7w)#[^
public String toString(){ Yl1@gw7
StringBuilder buff = new StringBuilder {NE;z<,*:
l)VMF44
(); Fg4eIE-/M
buff.append("{"); ^f!d8
V
buff.append("count:").append(count); #eE:hiu<v
buff.append(",p:").append(p); NLb/Bja
buff.append(",nump:").append(num); Ltcr]T(Ic
buff.append(",results:").append txr!3-Ne'!
4)9X) Qx
(results); oG@P M+{
buff.append("}"); #=t:xEz
return buff.toString(); ~2A<fL,-
} OAw/
"_'9KBd!
} _* 4
<
C& Nd|c
N!RyncJ