Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 m`A%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 CNrIIsJ
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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 _}6q{}jn:c
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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 0 p uY"[c
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分页支持类: ,FSrn~-j9
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java代码: A#y@`}]!'
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package com.javaeye.common.util; +cu^%CXT
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import java.util.List; \?fI t?
}
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publicclass PaginationSupport { %&<LNEiUN
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publicfinalstaticint PAGESIZE = 30; !nf-}ze{
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privateint pageSize = PAGESIZE; :!TIK1
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privateList items; 2umv|]n+l|
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privateint totalCount; TLa]O1=Bf.
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privateint[] indexes = newint[0]; X[$++p
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privateint startIndex = 0; eVh-_
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public PaginationSupport(List items, int bZwnaM4"F
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totalCount){ b{7E;KyY,
setPageSize(PAGESIZE); G;iEo4\?
setTotalCount(totalCount); .?W5{U
setItems(items); @z`@f"l
setStartIndex(0); JK_OZ
} 5jcte<
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public PaginationSupport(List items, int ~aK?cP
4_?7&G0(
totalCount, int startIndex){ 'fd1Pj9~$
setPageSize(PAGESIZE); ib6^x:HGU
setTotalCount(totalCount); ()T[$.(
setItems(items); G=9d&N
setStartIndex(startIndex); oMH.u^b]fT
} ^%T7. 1'x
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public PaginationSupport(List items, int ^eq</5q D
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totalCount, int pageSize, int startIndex){ :Ixx<9c.
setPageSize(pageSize); 9"{W,'r&d
setTotalCount(totalCount); j7QX,_Q
setItems(items); `TLzVB-j3
setStartIndex(startIndex); u,.3
} _"a=8a06G
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publicList getItems(){ },$0&/>ft
return items; g{k1&|
} ]3{0J
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publicvoid setItems(List items){ si4-3eC
this.items = items; .d<W`%[
} A#wEuX=[
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publicint getPageSize(){ [I*!
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return pageSize; xl9aV\W
} K,ej%Vtz
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publicvoid setPageSize(int pageSize){ YNdrWBf)
this.pageSize = pageSize; uzOYVN$t
} Aj>[z8!,
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publicint getTotalCount(){ Ka!I`Yf
return totalCount; W~n.Xeu{C
} C)-^<
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publicvoid setTotalCount(int totalCount){ m|tC24
if(totalCount > 0){ DbI!l`Vn4
this.totalCount = totalCount; v5}X+'
int count = totalCount / {lG@hN'
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pageSize; KxGX\
if(totalCount % pageSize > 0) {2d_"lHBt
count++; Njc%_&r
indexes = newint[count]; Z3KO90O!8
for(int i = 0; i < count; i++){ ='?:z2lJ
indexes = pageSize * q6#<[ 4?
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i; b,H[I!. %
} ;zTuKex~
}else{ Ol/\t
this.totalCount = 0; 6aO2:|:yP
} $"JpFT
} imB# Eo4eY
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publicint[] getIndexes(){ M5L{*>4|6
return indexes; K]oM8H1
} pE]?x$5U
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publicvoid setIndexes(int[] indexes){ BcWcdr+}9
this.indexes = indexes; `bI)<B
} `1` f*d
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publicint getStartIndex(){ 6SM:x]`##,
return startIndex; AbwbAm+
} FVsj;
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publicvoid setStartIndex(int startIndex){ pcS+o
if(totalCount <= 0) @ T;L$x
this.startIndex = 0; vE, 37
elseif(startIndex >= totalCount) or*HC&c7
this.startIndex = indexes Et2JxbD
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[indexes.length - 1]; |f( ~@Q:
elseif(startIndex < 0) |k 2" _
this.startIndex = 0; )+y G+
else{ 8;P2A\X
this.startIndex = indexes i%Z2wP.o
;^u*hZN[Up
[startIndex / pageSize]; q z&+=d@
} u+9<&)X0
} bUy,5gk-
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publicint getNextIndex(){ PaB!,<A
int nextIndex = getStartIndex() + e;YW6}'}
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pageSize; _W!p8cB
if(nextIndex >= totalCount) Iry
return getStartIndex(); G\gMC
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else 's
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return nextIndex; qOV[TP,
} CG]Sj*SA~
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - ;$j7H&UNQj
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pageSize; !LM<:kf.|
if(previousIndex < 0) .0HZNWRtb
return0; ]uL+&(cr
else Y$8JM
return previousIndex; t%1 ^Li
} O;Y:uHf
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} Kr`]_m
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抽象业务类 &F$:Q:* *
java代码: d5I f"8`@
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/** 8[%Ao/m
* Created on 2005-7-12 qa >Ay|92e
*/ [&S}dQ"
package com.javaeye.common.business; Oeya%C5'
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import java.io.Serializable; th5g\h%j*
import java.util.List; Wo$%9!W
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import org.hibernate.Criteria; cTZ.}eLh
import org.hibernate.HibernateException; ,38Eq`5&W
import org.hibernate.Session; Tsb{25`+
import org.hibernate.criterion.DetachedCriteria; 'fwU]Hm
import org.hibernate.criterion.Projections; &sVvWNO#2
import {Z;t ^:s#
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org.springframework.orm.hibernate3.HibernateCallback; 7\
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import BZK`O/
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org.springframework.orm.hibernate3.support.HibernateDaoS }A$WO{2
s Wjy6;
upport; ({}( qm
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import com.javaeye.common.util.PaginationSupport; @MR?6 n*k
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public abstract class AbstractManager extends X*oMFQgP
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HibernateDaoSupport { v`q\6i[-
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privateboolean cacheQueries = false; QvPD8B
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privateString queryCacheRegion; o6kNx>tc)
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publicvoid setCacheQueries(boolean AF\T\mtvRm
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cacheQueries){ 7XrfuG*L$
this.cacheQueries = cacheQueries; cvsz%:Vs
} LS>G4
]
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publicvoid setQueryCacheRegion(String pj|pcv^
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queryCacheRegion){ ?@6b>='!
this.queryCacheRegion = q(^Q3
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queryCacheRegion; c/W=$3
} RWq{Ff}Hk
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publicvoid save(finalObject entity){ Jwn AW}=
getHibernateTemplate().save(entity); f6<g3Q7Mu
} U4?(A@z9^
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publicvoid persist(finalObject entity){ $9
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getHibernateTemplate().save(entity); &(rWw Oo6
} ri~<~oB2:
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publicvoid update(finalObject entity){ )QKf7 [:
getHibernateTemplate().update(entity); m8]?hJY3l
} z;u>
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publicvoid delete(finalObject entity){ Tm]nEl)_
getHibernateTemplate().delete(entity); ,0$)yZ3*3,
} R/b4NGW@
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publicObject load(finalClass entity, EEy$w1ec
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finalSerializable id){ D6D1S/:ij'
return getHibernateTemplate().load Z~G my7h(
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(entity, id); &FdWFt=X
} gA#RM5x@
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publicObject get(finalClass entity, R_P}~l
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finalSerializable id){ wy1X\PJjH
return getHibernateTemplate().get }SyxPXs
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(entity, id); }H:F< z*
} +WJ(QZEhD
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publicList findAll(finalClass entity){ _S0+;9fhY
return getHibernateTemplate().find("from ajhEL?%D
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" + entity.getName()); H2gj=krK
} QA!_} N4n
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publicList findByNamedQuery(finalString P'@<:S|
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namedQuery){ Y+%sBqo@
return getHibernateTemplate < O*6T%;
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().findByNamedQuery(namedQuery); Q }k.JS~#
}
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publicList findByNamedQuery(finalString query, #4LFG\s
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finalObject parameter){ }Y(]6$uS
return getHibernateTemplate $V>98M>j
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().findByNamedQuery(query, parameter); ^^` Jcd/
} wJb#g0
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publicList findByNamedQuery(finalString query, pVp:@0h
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finalObject[] parameters){ x LBQ
return getHibernateTemplate 6Sj6i^"
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().findByNamedQuery(query, parameters); +#@"*yj3
} .k{ j]{k
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publicList find(finalString query){ Q~D`cc|]
return getHibernateTemplate().find IHfzZHy
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(query); @\_x'!R
} ` >!n
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publicList find(finalString query, finalObject _#e&t"@GS
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parameter){ gJt`?8t
return getHibernateTemplate().find *=" 8?Z
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(query, parameter); }G46g#_6d>
} Q "r_!f
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public PaginationSupport findPageByCriteria Wm'QP4`
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(final DetachedCriteria detachedCriteria){ Rr(* aC2P
return findPageByCriteria +!-~yf#RE
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~\nBjM2
} h5z)Lc^
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public PaginationSupport findPageByCriteria PHg48Y"Nd
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(final DetachedCriteria detachedCriteria, finalint /e\{
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startIndex){ `+lHeLz':
return findPageByCriteria 6< J
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(detachedCriteria, PaginationSupport.PAGESIZE, m^%|ZTrwN7
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startIndex); R)?{]]v
} HJ?+A-n/
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public PaginationSupport findPageByCriteria kpwt]]e*
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(final DetachedCriteria detachedCriteria, finalint k@>\LR/v
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pageSize, >e5 *prx+
finalint startIndex){ !U_K&f
return(PaginationSupport) _,Fny_u=;
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getHibernateTemplate().execute(new HibernateCallback(){ 7x]4`#u
publicObject doInHibernate Sydh2d
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(Session session)throws HibernateException { @4~=CV%j
Criteria criteria = Dq\ Jz~
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detachedCriteria.getExecutableCriteria(session); |XYEn7^r
int totalCount = eC
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((Integer) criteria.setProjection(Projections.rowCount \2[<XG(^
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()).uniqueResult()).intValue();
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criteria.setProjection Mj>}zbpk/
js^ ,(CS
(null); ~Vh(6q.oT
List items = Bsf7mcXz7z
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criteria.setFirstResult(startIndex).setMaxResults W^,S6!
S-+"@>{HJ
(pageSize).list(); s6*ilq1
PaginationSupport ps = + j+5ud`
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new PaginationSupport(items, totalCount, pageSize, 5F+APz7
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startIndex); QR?yG+VU
return ps; )CPM7>
} JG`Q;K
}, true); _Jz8{` "
} aeyNdMk-
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public List findAllByCriteria(final f8 /'%$N
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DetachedCriteria detachedCriteria){ A*h{Lsx;
return(List) getHibernateTemplate p Y)5bSA
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().execute(new HibernateCallback(){ U=Y)V%
publicObject doInHibernate S 6,4PP
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(Session session)throws HibernateException { Z#d&|5Xj
Criteria criteria = }TRAw#h
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detachedCriteria.getExecutableCriteria(session); h!@|RW&}qX
return criteria.list(); <^.=>Q0S\
} }_tl n
}, true); `cz2DR-"
} KAA-G2%M
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public int getCountByCriteria(final }K1 0Po'
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DetachedCriteria detachedCriteria){ F+ <Z<q
Integer count = (Integer) ] H~4
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getHibernateTemplate().execute(new HibernateCallback(){ a?}
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publicObject doInHibernate zIC;7 5#
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(Session session)throws HibernateException { '# NcZy
Criteria criteria = k-V,~c
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detachedCriteria.getExecutableCriteria(session); <P ,~eX(r
return @[<nQZw:
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criteria.setProjection(Projections.rowCount d4:`@*
CQ7{1,?2
()).uniqueResult(); G2 ]H6G$M
} !J1rRPV
}, true); +:=(#Y
return count.intValue(); {_N,=DQ!
} vE6mOM!_L
} ~0$NJrUy
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用户在web层构造查询条件detachedCriteria,和可选的 3P~o"a>
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 I
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PaginationSupport的实例ps。 I&?Qq k
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ps.getItems()得到已分页好的结果集 %+ 7p lM
ps.getIndexes()得到分页索引的数组 (Q[fS:U
ps.getTotalCount()得到总结果数 WH ?}~u9
ps.getStartIndex()当前分页索引 'ckQg=zPR
ps.getNextIndex()下一页索引 G)#$]diNuX
ps.getPreviousIndex()上一页索引 1"8yLvtn
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 sAo&
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 QY/hI`
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一下代码重构了。 1}hIW":3Sr
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我把原本我的做法也提供出来供大家讨论吧: hPq%Lc
kdz=ltw
首先,为了实现分页查询,我封装了一个Page类: -?]W*f
java代码: #QCphhG
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/*Created on 2005-4-14*/ )%rg?lI
package org.flyware.util.page; ]v[|B
T|&[7%F3"
/** PFUO8>!pA\
* @author Joa 2._X|~0a
* JvYPC
*/ f>'Y(dJ'W
publicclass Page { 01!s"wjf
V)Z70J<'
/** imply if the page has previous page */ U$oduY#
privateboolean hasPrePage; y"]n:M:(
y(R?
,wa=]
/** imply if the page has next page */ YV=QF
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privateboolean hasNextPage; 2|\A7.
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/** the number of every page */ d0'JC*
privateint everyPage; "5cM54Z0
k6`6Mjbc
/** the total page number */ Bq/:Nd[y
privateint totalPage; 7+./zN
Vcd.mE(t%
/** the number of current page */ .4.b*5
privateint currentPage; 5cx#SD&5/
}@if6(0
/** the begin index of the records by the current Qf@I)4'
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query */ UR:aD_h
privateint beginIndex; m*e{\)rd#
zy*/T>{#
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/** The default constructor */ kw2T>
public Page(){ &A#~)i5gF
rD>*j~_+P
} !w
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TAjh"JJIV
/** construct the page by everyPage ;lYHQQd!,
* @param everyPage P`r55@af4
* */ d[rv1s>i
public Page(int everyPage){ &.TTJsKG h
this.everyPage = everyPage; U%0Ty|$Y
} gGfoO[B
HF|oBX$_
/** The whole constructor */ w+1Gs
;
public Page(boolean hasPrePage, boolean hasNextPage, @p\}p Y$T
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int everyPage, int totalPage, tTd\|
int currentPage, int beginIndex){ |bgo;J/
this.hasPrePage = hasPrePage; @cU&n6C@
this.hasNextPage = hasNextPage; 8enEA^
this.everyPage = everyPage; :[;hu}!&
this.totalPage = totalPage; [w ;kkMJAy
this.currentPage = currentPage; \h8 <cTQ
this.beginIndex = beginIndex; `y+tf?QN
} hy|b6wF&
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/** e<r,&U$
* @return F;^F+H
* Returns the beginIndex. w3jO6*_ M
*/ vq34/c^
publicint getBeginIndex(){ =B.F;40
return beginIndex; j65<8svl
} gv5*!eI
8QMPY[{
/** !ct4;.2
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* @param beginIndex 7gRgOzWfV
* The beginIndex to set. m,fAeln
*/ -*.-9B~u
publicvoid setBeginIndex(int beginIndex){ 4tY ss
this.beginIndex = beginIndex; W`^@)|9^)
} E!S 78z:
nS>8bub30
/** n_'{^6*O
* @return S6fb f>[
* Returns the currentPage. Uix6GT;
*/ ~i 7^P9
publicint getCurrentPage(){ Mw9 \EhA
return currentPage; eF2|Wjl``;
} ToYAW,U[d
Hc`A3SMR
/** hpU2
* @param currentPage bJs9X/E
* The currentPage to set. R##~*>#
*/ y!xE<S&Y
publicvoid setCurrentPage(int currentPage){ {z|;Xi::"
this.currentPage = currentPage; .`&F>o(A
} 5ZBKRu
AlJ} >u
/** r(9~$_(vK
* @return XVU2T5s}
* Returns the everyPage. NIw\}[-Z0E
*/ 5xL~`-IA&v
publicint getEveryPage(){ 0Lb4'25.
return everyPage; Jec'`,Y
} H=
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/** cph:y
* @param everyPage m)oJFF
* The everyPage to set. [n}T|<
*/ Z@r.pRr'
publicvoid setEveryPage(int everyPage){ 6^DR0sO
this.everyPage = everyPage; 64
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} @e{^`\ l=<
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/** Dih3}X&jn$
* @return {AQ=<RDRF
* Returns the hasNextPage. 33}oO,}t,
*/ U,LTVYrO
publicboolean getHasNextPage(){ %Rsp;1Z
return hasNextPage; Sf8{h|71
} `jOX6_z?I
P~ &$l2
/** rXHv`ky
* @param hasNextPage VH:]@x//{
* The hasNextPage to set. Od|$Y+@6
*/ #^]n0!
publicvoid setHasNextPage(boolean hasNextPage){ mml
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this.hasNextPage = hasNextPage; .aflsUD
} yxc=Z0~1
V(E/'DR
/** ccL~#c0P7
* @return +sJrllrE(
* Returns the hasPrePage. zen*PeIrA^
*/ [
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publicboolean getHasPrePage(){ 4!wR_@W^El
return hasPrePage; L31|\x]
} 9HX =T%
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/** Pfs;0}h5
* @param hasPrePage M.>l#4s,'
* The hasPrePage to set. Ox@P6|m
*/ ^I+)o1%F
publicvoid setHasPrePage(boolean hasPrePage){ ,\@O(;
mF
this.hasPrePage = hasPrePage; ^urDoB:
} .(WQYOMl0
oqeSG.1
/** GDuMY\1
* @return Returns the totalPage. ^7Fh{q4IE
* -!
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*/ \!ej<T+JR>
publicint getTotalPage(){ y
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return totalPage; )[Yv?>ib
} /Js7`r=Rx
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/** Ggb5K8D*
* @param totalPage .AU)*7Gh
* The totalPage to set. )sT> i
*/ cSm%s
publicvoid setTotalPage(int totalPage){ B9J&=6`)
this.totalPage = totalPage; ;"m ,:5%
} _hk.2FV:3m
T'b_W,m~,u
} j.@\3'
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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 k Zq!&
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个PageUtil,负责对Page对象进行构造: 'Un" rts
java代码: )[|3ZP`
s4uhsJL V$
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/*Created on 2005-4-14*/ icgSe:Ci
package org.flyware.util.page; FJ6u.u
}:~x7|~s:
import org.apache.commons.logging.Log; L:'J
Bhg
import org.apache.commons.logging.LogFactory; 5hy""i
ih;]nJ]+-
/** ,1"KHv
* @author Joa }O4^Cc6
* q')R4=0
K
*/ `kJ^zw+
publicclass PageUtil { ` 5C~
D= h)&
privatestaticfinal Log logger = LogFactory.getLog =%BZ9,l
\R;`zuv
(PageUtil.class); 6efnxxY}sa
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/** G"XVn~]
* Use the origin page to create a new page VH1d$
* @param page 1{r)L{]
* @param totalRecords }7.PH'.8
* @return ;y2/-tL?
*/ d:U9pC$
publicstatic Page createPage(Page page, int [`):s= FC
jav#f{'
totalRecords){
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return createPage(page.getEveryPage(), #"5 Dk#@
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page.getCurrentPage(), totalRecords); v3jg~"!
} =Fr(9(
)6J9J+%bi
/** 6ZQwBS0Y
* the basic page utils not including exception Q(oN/y3,
7[}xP#Z
handler KPj\-g'A
* @param everyPage =HlQ36;*
* @param currentPage X]dwX%:Z!j
* @param totalRecords !f+H,]D"
* @return page 9amaL~m
*/ C-H@8p?T
publicstatic Page createPage(int everyPage, int `u&Zrdr,
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currentPage, int totalRecords){ ixT:)|'i
everyPage = getEveryPage(everyPage); )}?#
currentPage = getCurrentPage(currentPage); XUlS\CH@{
int beginIndex = getBeginIndex(everyPage, Uh):b%bS;J
9
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currentPage); rq/I` :
int totalPage = getTotalPage(everyPage, fL=~NC"
-B$2\ZE
totalRecords); la+[bm<v
boolean hasNextPage = hasNextPage(currentPage, SrK) t.oK
8{X"h#
totalPage); 3^6
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boolean hasPrePage = hasPrePage(currentPage); k-{<=>uM
sH[ROm
returnnew Page(hasPrePage, hasNextPage, 0PrLuejz
everyPage, totalPage, t?'!$6
currentPage, ~S7D>D3S
aiu5}%U
beginIndex); @0u~?!g@
} DS[#|
n@,G8=J?
privatestaticint getEveryPage(int everyPage){ rMhB9zB1
return everyPage == 0 ? 10 : everyPage; ]h
%Wiw
} &H`jL4S
4s*ZS}]
o
privatestaticint getCurrentPage(int currentPage){ S-|)QGxV6
return currentPage == 0 ? 1 : currentPage; vz7J-CH
} @6]sNm
xM&Wgei]10
privatestaticint getBeginIndex(int everyPage, int 8;+B*+%@n
'GS"8w~j
currentPage){ CyXRi}W.
return(currentPage - 1) * everyPage; |* ;B
} ub\MlSr
h*u
privatestaticint getTotalPage(int everyPage, int tE`u(B,
|~vI3]}fx
totalRecords){ .w8J*JZ
int totalPage = 0; r 0iK
l)&X$3? tz
if(totalRecords % everyPage == 0) ''\Ov
totalPage = totalRecords / everyPage; Dw<bn<e-
else +N:o-9
totalPage = totalRecords / everyPage + 1 ; zM(vr"U
=aBctd:eX`
return totalPage; ne_TIwf w-
} t~#zMUfac
mSb#Nn6W
privatestaticboolean hasPrePage(int currentPage){ O%5
r[
return currentPage == 1 ? false : true; &N\jG373
} qfMo7e@6*
E4~<V=2l
privatestaticboolean hasNextPage(int currentPage, ^!<BQP7
L"4mL,
int totalPage){ ^5h]Y;tx
return currentPage == totalPage || totalPage == ;E3>ay6m8
<?riU\-]y
0 ? false : true; ='s(|
} F.=2u"[*&
< v@9#c
q$B>|y U
} EkjN{$*
O\"3J(y,
xQ^E"Q,1
YW( Qmo7
pH"#8O&
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 iiS-9>]/
P'Ux%Q+B>
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 UJCYs`y
IpcNuZo9&
做法如下: lE&&_INHQ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 AK*LyR?
t>`asL
的信息,和一个结果集List: ~nh:s|l6%M
java代码: pxCK;]
S/e2P|}
C(#u[8
/*Created on 2005-6-13*/ %}Ss,XJ
package com.adt.bo; x:7b/j-
!`,Sfqij
import java.util.List; QD:{U8YbF$
LXC9I/j/
import org.flyware.util.page.Page; 7|$:=4
~,oMz<iMV
/** 3c]b)n~Y
* @author Joa gT0BkwIV
*/ VFURAYS
publicclass Result { FrL]^59a
7 /VK##z
private Page page; b`~p.c%(
w&o&jAb-M
private List content; $Bs {u=+w
)ttUWy$w
/** ,+meT`'vn
* The default constructor 7Z\--=;|[:
*/ C9n?@D;S
public Result(){ }%'?p<^M
super(); hRrn$BdLX
} XINu=N(g
g1W.mAA3B
/** #><.oreXq
* The constructor using fields 'E/^8md>
* D(AXk8Vub
* @param page C/vIEYG4
* @param content AGQ#$fh>7=
*/ J;{N72
public Result(Page page, List content){ WaVtfg$!
this.page = page; $RIecv<e_
this.content = content; t\{'F7
} @|63K)Xy
BGD8w2
/** ]
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* @return Returns the content. |"/8XA
*/ %_RQx2
publicList getContent(){ D#il*
return content; /H(?
2IHC
} +;N2p1ZBf
VEqS;~[
/** :(!`/#6H
* @return Returns the page. m'6&9Jak
*/ #\.,? A}9
public Page getPage(){ ]B%v+uaW
return page; Po__-xN>Q
} kb{]>3Y"
sk,ox~0R
/** JEahGzO
* @param content >VP=MbN
* The content to set. 6K-_pg]
*/ <acUKfpY
public void setContent(List content){ Xm%D><CC8"
this.content = content; aqRhh=iS
} yp KUkH/
hb zC#@q
/** "a
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* @param page F)&@P-9+
* The page to set. aY'C%^h]
*/ ]iN'x?Fo
publicvoid setPage(Page page){ :PIF07$xl
this.page = page; :km61
} Oiz ,w7LRh
} Ljxz.2LGr
tyXuG<
s+,OxRVw(
Zhh2v>QOy
?s\:hNNY
2. 编写业务逻辑接口,并实现它(UserManager, 2N~Fg^xB
m?pstuUK(
UserManagerImpl) "HElB9
java代码: lef2 X1w}!
v 1z
\K@'Z
/*Created on 2005-7-15*/ Cjqklb/
package com.adt.service; iop2L51eJ
C([phT;
import net.sf.hibernate.HibernateException; 3L833zL
e+$p9k~
import org.flyware.util.page.Page; +$C4\$t
8jd;JPz@\
import com.adt.bo.Result;
ZHU5SXu
[ oL.+
/** h U`wVy
* @author Joa Gn|F`F
*/ M m[4yP%
publicinterface UserManager { 8oUpQcim
.y_/U wu
public Result listUser(Page page)throws R:e<W/P"
hd>aZ"nm1
HibernateException; _/uFsYC
K/tRe/t}
} ,k{#S?:b
@.b+av4J
])|d"[ur=
//T>G_1
)PG6gZYW
java代码: T]t+E'sQ
A<5ZF27
J7= +
/*Created on 2005-7-15*/ IE;~?W"
package com.adt.service.impl; _hRcc"MS`
f!oT65Vmi
import java.util.List; %+8F'&X
P_?gq>E8
import net.sf.hibernate.HibernateException; |]J>R
l>Z5 uSG
import org.flyware.util.page.Page; .z)%)PVV
import org.flyware.util.page.PageUtil; w[9|cgCY
Bg&i63XL$$
import com.adt.bo.Result; /2UH=Q!x4E
import com.adt.dao.UserDAO; ;A|-n1e>Hc
import com.adt.exception.ObjectNotFoundException; lsNrAA%m
import com.adt.service.UserManager; @y='^DQ*
9:ze{ c $
/** LQtj~c>X-|
* @author Joa b7NM#Hb
*/ Wc,~ {
publicclass UserManagerImpl implements UserManager { w.H%R-Be
OUeyklw
private UserDAO userDAO; RIb4!!',c
)-0kb~;|
/** $nb[G$
* @param userDAO The userDAO to set. 3a?o3=
*/ p[hZ@f(z
publicvoid setUserDAO(UserDAO userDAO){ b%<9Sn
this.userDAO = userDAO; gZLP\_CL
} IhA5Wt0j
12;8o<~
/* (non-Javadoc) ZAv,*5&<
* @see com.adt.service.UserManager#listUser 3&u&x(
\@8+U;d
(org.flyware.util.page.Page) z.GMqW%B
*/ K8>zF/# +
public Result listUser(Page page)throws BybW)+~
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HibernateException, ObjectNotFoundException { D}dn.$
int totalRecords = userDAO.getUserCount(); iVB86XZ`
if(totalRecords == 0) bn^{c
throw new ObjectNotFoundException PV9pa/`@
`S6x<J&T\/
("userNotExist"); Sx?ua<`:d
page = PageUtil.createPage(page, totalRecords); JHz
[ 7
List users = userDAO.getUserByPage(page); Min
^>
returnnew Result(page, users); ebT:/wu,2
} SS$[VV
*a58ZI@
} k p<OJy
3[O=xXB
pPc TrN'
|/09<F:L[
IB[)TZ2m
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]}U*_rM:
n^z]q;IN2.
询,接下来编写UserDAO的代码: *^f<W6xc
3. UserDAO 和 UserDAOImpl: _59huC.
java代码: a"FCZ.O1
+6';1Nb@
Zrvz;p@~
/*Created on 2005-7-15*/ ;?8_G%va
package com.adt.dao; ?,&
tNP{jq
\De{9v
import java.util.List; <)u`~$n2
8ELCs<xI
import org.flyware.util.page.Page; p(~Yx3$*
eu(:`uu
import net.sf.hibernate.HibernateException; T;,cN7>>O
5<UVD:~z
/** DV _2P$tT|
* @author Joa Y8o)FVcyNy
*/ 7cTV?nc
publicinterface UserDAO extends BaseDAO { `-3Ow[
1XD,uoxB
publicList getUserByName(String name)throws ,6om\9.E@
C}_ ojcR
HibernateException; ;`^WGS(3.%
Kac' ;1
publicint getUserCount()throws HibernateException; rNB_W.
B oC5E#;G
publicList getUserByPage(Page page)throws W3 'q\+
P/Q!<I
HibernateException; K#pNec
\=6l9Lrj>h
} &ge "x{,?
(H
->IV
d4?Mi2/jF
R'C2o]
/+@p7FqlE
java代码: RLLTw ?]$
4iKgg[)7`=
PX<J&rx
/*Created on 2005-7-15*/ %k'!Iq+
package com.adt.dao.impl; J/[=p<I)
{\c(ls{
import java.util.List; ?XA2&
w+1|9Y
import org.flyware.util.page.Page; 0V'nK V"|
A29gz:F(
import net.sf.hibernate.HibernateException; m]5Cq6
import net.sf.hibernate.Query; G>1eFBh }
J6L K
import com.adt.dao.UserDAO; L5
veX}
UrYZ`J
/** PYM(Xz$
* @author Joa qoj$]
*/ ]3KhgK%c8
public class UserDAOImpl extends BaseDAOHibernateImpl Gu2P\I2zx
d5D$&5Ec
implements UserDAO { /J:bWr
/4`
0?/V
/* (non-Javadoc) <iH`rP#
* @see com.adt.dao.UserDAO#getUserByName ,'p2v)p^4
d*~ICir7
(java.lang.String) %2XHNW
*/ UG'9*(*
publicList getUserByName(String name)throws +(C6#R<LI
11<KpxKpk
HibernateException { p' +
String querySentence = "FROM user in class Gcig*5
&8] d }-e
com.adt.po.User WHERE user.name=:name"; +;#Y]xy:
Query query = getSession().createQuery b#K:_ac5
%=/)
(querySentence); oE(7v7iY
query.setParameter("name", name); }MHCd)78b
return query.list(); 8"fD`jtQ
} /XhIx\40l
=u+d_'P7-R
/* (non-Javadoc) 2UFv9
* @see com.adt.dao.UserDAO#getUserCount() )e a :Q?
*/ (Nx;0"5IX
publicint getUserCount()throws HibernateException { h\PHKC2
int count = 0; J,AR5@)1
String querySentence = "SELECT count(*) FROM _c,'>aH=
+=.W<b
user in class com.adt.po.User"; `.x
Fiyc
Query query = getSession().createQuery A@sZ14+f
|m80]@>
(querySentence); XI9js{p
count = ((Integer)query.iterate().next uwjGDw
`kU/NKq
()).intValue(); =9"W@n[>W
return count; p~9vP)74u
} OnK~3j
S6AU[ASY.
/* (non-Javadoc) o]p|-<I Q
* @see com.adt.dao.UserDAO#getUserByPage JXu$ew>q
US%^#D q
(org.flyware.util.page.Page) qt;y2gf=
*/ Hrz f'a|^
publicList getUserByPage(Page page)throws >&p0d0
t$A%*JBKm
HibernateException { %"af748!+D
String querySentence = "FROM user in class IjR'Qou5
RW }"2
com.adt.po.User"; `/~8}Y{
Query query = getSession().createQuery -tyK~aasQ
4=Krq6{
(querySentence); H8`(O"V
query.setFirstResult(page.getBeginIndex()) iTV) NsC}
.setMaxResults(page.getEveryPage()); $pFo Rv
return query.list(); ! ykx^z
} 9$|Gfyv
]- 4QNc=
}
NsJ(`zk:
*0>mB
.?!N^_ Ez3
V`7FKL@"
^pe{b9c
至此,一个完整的分页程序完成。前台的只需要调用 +{L<? "
YBP:q2H
userManager.listUser(page)即可得到一个Page对象和结果集对象 K!] 1oy'V
M>>qn_yq4
的综合体,而传入的参数page对象则可以由前台传入,如果用 ,i,q!M{-
v0ES;
webwork,甚至可以直接在配置文件中指定。 [w&$| h:;
+C(/Lyo}
下面给出一个webwork调用示例: EB_NK
java代码: d R]Q$CJ
o`q_wdy?
YcN!T"wJ@
/*Created on 2005-6-17*/ C,pJ`:P
package com.adt.action.user; '^FGc
lME)?LOI
import java.util.List; /M*a,o
zdEPDdB
import org.apache.commons.logging.Log; }LijnHH.
import org.apache.commons.logging.LogFactory; LI6hEcM=
import org.flyware.util.page.Page; DANw1_X\
)h8\u_U
import com.adt.bo.Result; QtJg^2@
import com.adt.service.UserService; *s>BG1$<
import com.opensymphony.xwork.Action; 't9hXzAfW
D.1J_Y=9
/** {!K-E9_,S
* @author Joa HCa
*/ wu4NLgkE
publicclass ListUser implementsAction{ NSFs\a@1
~~6^Sh60g
privatestaticfinal Log logger = LogFactory.getLog yGsz2T;w
B-T/V-c7
(ListUser.class); _"#!e{N|
n]u<!.X
private UserService userService; yH<$k^0r*
OHflIeq#@
private Page page; $Tb G+Eb8
a<A+4uXyD
privateList users; Ii^5\v|C
%O<%UmR
/* 8B#GbS
K
* (non-Javadoc) M!tXN&V]
* A?oXqb
* @see com.opensymphony.xwork.Action#execute() bug
Ot7
*/ gt7VxZ
publicString execute()throwsException{ ]Bm>-*@0N
Result result = userService.listUser(page); !xKJE:4/,m
page = result.getPage(); /De^
users = result.getContent(); @5[kcU>
return SUCCESS; ]Y| 9?9d
} s #S%#LM
vc]cNz:mQ
/** Y&^ P"Dw
* @return Returns the page. 1 `7<2w
*/ 8l"O(B'#Z
public Page getPage(){ C( id=F
return page; $\"9<o|h
} -dO'~all
7lo|dg80
/** wCHR7X0*b
* @return Returns the users. 033T>qY
*/ N<L`c/
publicList getUsers(){ gXH[$guf
return users; kGUJ9Du
} vw)7 !/#
u?[ q=0.J7
/** 3F#+~^2
* @param page Z^9/v
* The page to set. )C. yF)Ql
*/ "z*:'8;E
publicvoid setPage(Page page){ ?~QIALA
this.page = page; U5]pi+r
} t
nS+5F
_7D _72
/** 4TwQO$C
* @param users AC.A'|"]i
* The users to set. dk==?
*/ 1,V`8 [
publicvoid setUsers(List users){ Zh/Uu6
this.users = users; e62Dx#IY
} k5&bq2)I
) ){xlFA}
/** H\GkW6
* @param userService w~@-9<^K]v
* The userService to set. (.Lrmf@hI7
*/ lZQ/W:OE
publicvoid setUserService(UserService userService){ $oLU; q%
this.userService = userService; pU!o7>p
} dtAbc7
} SxjCwX">
./p|?pu
do-c1;M
CWO=0_>2
m ga6[E<
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Se!)n;?7Sw
Fn^C{p^
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 {FI\~q
vSW
L$Y2
么只需要: b59{)u4F
java代码: 3qQUpm+
= zl=SLe
~^vC,]hU
<?xml version="1.0"?> -K[782Q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork p[2GkP
&)pK%SAM
1.0//EN" "http://www.opensymphony.com/xwork/xwork- fB+b}aoV
ap}5ElMR
1.0.dtd"> _iEj
gq5qRi`q
<xwork> $A$@|]}p
1IgHc.s
<package name="user" extends="webwork- > 4oY 3wk8
1zktU.SZ
interceptors"> A{<xc[w;p
_B,_4}
<!-- The default interceptor stack name T!Sj<,r+j
vRPS4@9'
--> }xFi&
<
<default-interceptor-ref -iCcoA
xiyxrR;
name="myDefaultWebStack"/> \O7J=6fn
XV'fW~j\
<action name="listUser" =ex'22
jK8'T_Pah
class="com.adt.action.user.ListUser"> P.sgRsL
<param k:#6^!b1
l
oqvi
name="page.everyPage">10</param> Gowp
<9 F
<result MjaUdfx
D*vm
cSf
name="success">/user/user_list.jsp</result> Pj7gGf6v
</action> CQODXB^
FyG6!t%
</package> 0>!/rR7
WP-jtZ?!"
</xwork> A6ewdT?>,
Qrz4}0
#X.+
~DLIz g7p!
'Zk<l#"}
Wn!G.(Jq
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 #Nte^E4
he)ulB
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。 |t\|:E>" }
uC~g#[I QM
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 .9LL+d
ke/_k/
W'_/6_c$!
r@T| e
=:h3w#_c
我写的一个用于分页的类,用了泛型了,hoho R V!o4"\]
Z{{t^+XG
java代码: `HUf v@5
!v!N>f4S$
iUr xJh
package com.intokr.util; dDKqq(9(`
L)-*,$#<oW
import java.util.List; n_$yV:MuT!
6CNS%\A
/** ^{[`=P'/
* 用于分页的类<br>
U
5`y
* 可以用于传递查询的结果也可以用于传送查询的参数<br> g=A$<