Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <try%p|f
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 \sXmMc
fu7[8R"{
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 [3bwbfHhi
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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 .,iw2:
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。 Xf'
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分页支持类: %Tm'aY"
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java代码: YRT}fd>R&
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package com.javaeye.common.util; =,}!Ns{k
2[bR6 T89
import java.util.List; hF{mm(qyv
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publicclass PaginationSupport {
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publicfinalstaticint PAGESIZE = 30; RAXJsF^5o
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privateint pageSize = PAGESIZE; lf7H8k, -
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privateList items; KTS7)2ci
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privateint totalCount; c+
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privateint[] indexes = newint[0]; *Sp O|*'
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privateint startIndex = 0; wE=8jl*
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public PaginationSupport(List items, int v(WL 3[y;
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totalCount){ rBL_]\$7}
setPageSize(PAGESIZE); D/!G]hx
setTotalCount(totalCount); (l,YI"TzT
setItems(items); {N8rZ [Oo
setStartIndex(0); c9 TkIe
} Z{>Y':\?<
Vt 5XC~jK
public PaginationSupport(List items, int Uu<sntyv
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totalCount, int startIndex){ _[6+FdS],
setPageSize(PAGESIZE); yyYbB ]D
setTotalCount(totalCount); pRfHbPV?
setItems(items); =I*ZOE3n
setStartIndex(startIndex); dXr
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} .M#>@~XR
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public PaginationSupport(List items, int )fcpE,g'
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totalCount, int pageSize, int startIndex){ >Sl:Z ,g;
setPageSize(pageSize); Sv[_BP\^h
setTotalCount(totalCount); XcW3IO
setItems(items); 7.=s1~p
setStartIndex(startIndex); "B{xC}Tw
} P)
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publicList getItems(){ jYssz4)tp
return items; F_
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} U8 @*I>vA
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publicvoid setItems(List items){ gl4
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this.items = items; "MKsSty
} `rFGSq$9
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publicint getPageSize(){ t7&
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return pageSize; _ -FQ78C
} CMB$RLf
C'#)bX{
publicvoid setPageSize(int pageSize){ 6j.(l4}
this.pageSize = pageSize; o]k]pNO
} 2H0q\zZ
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publicint getTotalCount(){ 9n2%7dLQ*
return totalCount; %.}
} %1l80Z
st^N QL
publicvoid setTotalCount(int totalCount){ UVi/Be#|
if(totalCount > 0){ 5 s2}nIe
this.totalCount = totalCount; HGMH
g
int count = totalCount / Ptxc9~k
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pageSize; nWg)zj:
if(totalCount % pageSize > 0) |Szr=[
count++; 9S`b7U=P
indexes = newint[count]; t,Rn
for(int i = 0; i < count; i++){ G\+MT(&5
indexes = pageSize * ymJw{&^am
<Gt{(is
i; Hm[!R:HW,S
} hndRgCo
}else{ S~`AnX3!
this.totalCount = 0; z:?
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} {dH<Un(4Z
} Z4tq&^ :c=
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publicint[] getIndexes(){ 3S21DC@Y
return indexes; xVo)!83+Q
} [Cr~gd+q
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publicvoid setIndexes(int[] indexes){ _A~gqOe
this.indexes = indexes; E^ti!4{<
} \?IwR]@y
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publicint getStartIndex(){ {N`<e>A]{
return startIndex; +=xRr?F
} f@X*Tlx^|
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publicvoid setStartIndex(int startIndex){ Oc=PJf%D#
if(totalCount <= 0) lBC-G*#
this.startIndex = 0; zIm!8a
elseif(startIndex >= totalCount) &xT~;R^
this.startIndex = indexes ZX}"
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[indexes.length - 1]; 3Q"+
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elseif(startIndex < 0) [l{eJ/W
this.startIndex = 0; r\D8_S_
else{ :cz]8~i\
this.startIndex = indexes c3BL2>c
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[startIndex / pageSize]; O/~^}8TLL
} f.CI.aozW
} K?I&,t_*R
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publicint getNextIndex(){ -L3RzX
int nextIndex = getStartIndex() + ^@> Qiy
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pageSize; =l9#/G#R
if(nextIndex >= totalCount) (LPc\\Vv
return getStartIndex(); d8I:F9
else J4X35H=Z
return nextIndex; tfQq3 #
} qa?y lR"kA
9^olAfX`dB
publicint getPreviousIndex(){ 2"^9t1C2
int previousIndex = getStartIndex() - ~(S4/d5
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pageSize; TR20{8"
if(previousIndex < 0) -qF| Y
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return0; rpWy 6oD
else #+\G-
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return previousIndex; 9mm(?O~'p
} `7ZJB$7D|*
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} _\[G7
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抽象业务类 6Fb~`J~s
java代码: dG+xr!
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/** [t'"4
* Created on 2005-7-12 \:7EKzQ
*/ //|Vj | =
package com.javaeye.common.business; Hq$|j,&?
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import java.io.Serializable; vS#]RW&j
import java.util.List; :P~Owz
7a net
import org.hibernate.Criteria; w (1a{m?ht
import org.hibernate.HibernateException; >d\I*"C+d
import org.hibernate.Session; kvn6
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import org.hibernate.criterion.DetachedCriteria; 470Pig>I8
import org.hibernate.criterion.Projections; DAi[3`C
import t1S~~FLE
Qt 2hb
org.springframework.orm.hibernate3.HibernateCallback; ^p/mJ1/s7
import cO9Aw !
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org.springframework.orm.hibernate3.support.HibernateDaoS R2@u[
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upport; 'iK0Wr
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import com.javaeye.common.util.PaginationSupport; Dl{Pd`D
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public abstract class AbstractManager extends Z)%p,DiNM
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HibernateDaoSupport { $P_Y8:
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privateboolean cacheQueries = false; \BW(c)Q
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privateString queryCacheRegion; f`e.c_n(
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publicvoid setCacheQueries(boolean R0[Gfq9M=
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cacheQueries){ 0P 42C{>'w
this.cacheQueries = cacheQueries; 5]E5 V@C
} ojri~erJE?
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publicvoid setQueryCacheRegion(String vNIQc "\-
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queryCacheRegion){ R#>E{[9
this.queryCacheRegion = {YFru6$
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queryCacheRegion; 4.TG&IQ
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} U' Cp3>
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publicvoid save(finalObject entity){ <3KrhhH
getHibernateTemplate().save(entity); ;<\*(rUe
} bu-
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publicvoid persist(finalObject entity){ 5|Qr"c$p
getHibernateTemplate().save(entity); xlAaIo)T
} `F#KXk
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publicvoid update(finalObject entity){ U!4 ^;
getHibernateTemplate().update(entity); /_P`xm+=AC
} Tb^9J7]
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publicvoid delete(finalObject entity){ Zh@\+1]
getHibernateTemplate().delete(entity); f+&yc'[
} |@RO&F
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publicObject load(finalClass entity, 0Ko,S(M_
@OpcS>:R
finalSerializable id){ vjpe'zx
return getHibernateTemplate().load (ZYOm
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(entity, id); {q^KlSjm
} pmC@ fB
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publicObject get(finalClass entity, =GF+hM/~
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finalSerializable id){ IH5thL@D
return getHibernateTemplate().get 7?Fl [FW$
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(entity, id);
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} W6pS.}
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publicList findAll(finalClass entity){ \vI_%su1N
return getHibernateTemplate().find("from |l9AgwDg
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" + entity.getName()); bnlL-]]9z
} R~`Y6>o~9:
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publicList findByNamedQuery(finalString QwhPN'U
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namedQuery){ z, OMR`W
return getHibernateTemplate &HWH
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().findByNamedQuery(namedQuery); <C&UDj
} nJ,56}
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publicList findByNamedQuery(finalString query, o` e~1
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finalObject parameter){ 6c2fqAF>i
return getHibernateTemplate 9DIG K\
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().findByNamedQuery(query, parameter); |aZ^K\yI F
} {Z|C
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publicList findByNamedQuery(finalString query, O
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finalObject[] parameters){ <a'j8pw9i
return getHibernateTemplate Z8m/8M
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().findByNamedQuery(query, parameters); \UXQy{Ex
} 69_c,(M0
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publicList find(finalString query){ >6@UjGj54
return getHibernateTemplate().find }RD,JgmV
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(query); 3,pRmdC
} pM>.z9
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publicList find(finalString query, finalObject }b1P!xb!A
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parameter){ *{XbC\j
return getHibernateTemplate().find F.JE$)B2EX
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(query, parameter); " I:j a7
} 6CCM7
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public PaginationSupport findPageByCriteria Z{%h6""
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(final DetachedCriteria detachedCriteria){ {Bu^%JEn
return findPageByCriteria +|^rz#X
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); _m;Y'
} K !`t EW[
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public PaginationSupport findPageByCriteria 9HWtdJ+^C=
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(final DetachedCriteria detachedCriteria, finalint la
f b^
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startIndex){ D (yRI
return findPageByCriteria z~Gi/Ln
sY=$\hj
(detachedCriteria, PaginationSupport.PAGESIZE, $n!saPpxS
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startIndex); YMC*<wXN
} ga VWfG
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public PaginationSupport findPageByCriteria (J5E]NV
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(final DetachedCriteria detachedCriteria, finalint sAWUtJ
6!O~:\`DJ
pageSize, ,{7Z OzA
finalint startIndex){ Yaht<Hy
return(PaginationSupport) "\Z.YZUa\
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getHibernateTemplate().execute(new HibernateCallback(){ RoT}L#!!
publicObject doInHibernate #D&eov?
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(Session session)throws HibernateException { YR^J7b\
Criteria criteria = ,)|nxX
+.:- :
detachedCriteria.getExecutableCriteria(session); QVsOB$
int totalCount = `~F=
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((Integer) criteria.setProjection(Projections.rowCount LW
8LD|@
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()).uniqueResult()).intValue(); TDq(%IW
criteria.setProjection 9s7sn*aB#5
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(null); :>c33X}
List items = V'K1kYb
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criteria.setFirstResult(startIndex).setMaxResults |>Qj]
%77v'Pz1
(pageSize).list(); ;*Ldnj;B
PaginationSupport ps = ]nY,%XE
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new PaginationSupport(items, totalCount, pageSize, h(l4\)
]yiwdQ
startIndex); ZF!cXo7d
return ps; w9Bbvr6
} SvLI%>B=9
}, true); >08'+\~:b
} * G!C 'w\$
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public List findAllByCriteria(final SfLZVB
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DetachedCriteria detachedCriteria){ c@>Tzk%?"
return(List) getHibernateTemplate FL*qV"r^n
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().execute(new HibernateCallback(){ )O*\}6:S
publicObject doInHibernate 3|x*lmit
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(Session session)throws HibernateException { nLicog)!I
Criteria criteria = F!(Vg
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detachedCriteria.getExecutableCriteria(session); I7,5ID4pn
return criteria.list(); F,5~a_GP?
} 3 }~.#`QeY
}, true); wrI66R}@
} (?4m0Sn>#h
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public int getCountByCriteria(final G'<:O(Imu
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DetachedCriteria detachedCriteria){ 1k"<T7K
Integer count = (Integer) 0vR
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getHibernateTemplate().execute(new HibernateCallback(){ +L(|?|i8
publicObject doInHibernate @
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(Session session)throws HibernateException { n<q1itjD
Criteria criteria = o?5m^S14[1
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detachedCriteria.getExecutableCriteria(session); fSc)PqLP
return ,Y9bXC8+dU
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criteria.setProjection(Projections.rowCount v
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()).uniqueResult(); 8_$[SV$q
} JX!z,X?r4
}, true); k4T`{s}e
return count.intValue(); HE!"3S2S&+
} 0MpZdJ
} =)b!M^=X-a
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用户在web层构造查询条件detachedCriteria,和可选的 c o 8bnH
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 nMM:Tr
~cr##Ff5
PaginationSupport的实例ps。 iy!SqC
@=<B8VPJd
ps.getItems()得到已分页好的结果集 >G9YYt~
ps.getIndexes()得到分页索引的数组 *RYok{w
ps.getTotalCount()得到总结果数 ^O6eFD U
ps.getStartIndex()当前分页索引 xqSoE[<v
ps.getNextIndex()下一页索引 VEsIhjQ
ps.getPreviousIndex()上一页索引 S$N!Dj@e;
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 x`:c0y9uG
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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 XgI;2Be+&a
~`97?6*Ra
一下代码重构了。 t7-6A
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我把原本我的做法也提供出来供大家讨论吧: utu
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首先,为了实现分页查询,我封装了一个Page类: P(%^J6[>
java代码: fK|P144
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/*Created on 2005-4-14*/ oNhCa>)/
package org.flyware.util.page; 1K#%mV_
=f?vpKq40
/** b|-}?@&7&q
* @author Joa i&TWIl8
* cY^'Cj
*/ b($9gre>mI
publicclass Page { QQ,V35Vp[
+mPVI
/** imply if the page has previous page */ 5pU/X.lc
privateboolean hasPrePage; 6e>P!bo
j=dGNi)R
/** imply if the page has next page */ x,NV{uG$n
privateboolean hasNextPage; 8'PK}heBU
2#(dfEAy
/** the number of every page */ 6]r#6c%
privateint everyPage; !o`riQLs>
r]0>A&,
/** the total page number */ vRh)o1u)
privateint totalPage; )7C+hQe
Q h{P>}
/** the number of current page */ !^'6&NR#K
privateint currentPage; ]f~!Qk!I7r
dv Vz#
/** the begin index of the records by the current <v6W
l\
$[g#P^
query */ 5?Ukf$)x
privateint beginIndex; MTip4L W9
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/** The default constructor */ ^[&,MQU{7
public Page(){ Pcjrv:0$
l(9AwVoAR|
} ^z`d2it
Vx{
/** construct the page by everyPage O\SH;y,N
* @param everyPage m3~_uc/+D
* */ O"X:3srJ`
public Page(int everyPage){ M._;3_)%/
this.everyPage = everyPage; ]O>AD6P
} _T_6Yl&cf)
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/** The whole constructor */ yl&s!I
public Page(boolean hasPrePage, boolean hasNextPage, )5NWUuH 5
7p-
RPC
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int everyPage, int totalPage, 8|(],NyEJ
int currentPage, int beginIndex){ t3AmXx
this.hasPrePage = hasPrePage; u* G+=aV.6
this.hasNextPage = hasNextPage; UfIr"bU6
this.everyPage = everyPage; b!e0pFS;
this.totalPage = totalPage; (*b<IGi;
this.currentPage = currentPage; :dQRrmM
this.beginIndex = beginIndex; mo+!79&
} \H9:%Tlp~4
5$$#d_Gj
/** FJ^\K+;
* @return ^ir)z@P?V
* Returns the beginIndex. x]@z.Yj
*/ B&7NF}CF2
publicint getBeginIndex(){ S dN&%(ZE
return beginIndex; %NfXe[T
} 0@[*~H0{n
Y9gw
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/** fs:yx'mxV
* @param beginIndex `*elzW
* The beginIndex to set. =@pD>h/~
*/ -Lq2K3JHyn
publicvoid setBeginIndex(int beginIndex){ ][b|^V
this.beginIndex = beginIndex; &2U%/JqY
} Faa>bc~E
G"m?2$^-A
/** xticC>
* @return "*t0
t
* Returns the currentPage. [& Z-
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*/ ] jY^*o[
publicint getCurrentPage(){ {%CW!Rc
return currentPage; kG{};Vm
} 8sU5MQ5
&F/-%l!
/** Q"B8l[
* @param currentPage )bR0>3/
* The currentPage to set. 7y&6q`y E
*/ nu7 R
publicvoid setCurrentPage(int currentPage){ nGe4IY\-w
this.currentPage = currentPage; (# mvDz
} E
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/** j}tM0Ug.U
* @return p"c6d'qe
* Returns the everyPage. dq@
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*/ }^0'IAXi
publicint getEveryPage(){ qJ(uak
return everyPage; !'~L dl
} H8I)D& cw
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/** &6C]|13;
* @param everyPage uS,?oS
* The everyPage to set. )c&ya|h
*/ 38T]qz[Sn
publicvoid setEveryPage(int everyPage){ u<uc"KY=
this.everyPage = everyPage; br
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} yf0v,]v[
8b.k*,r>
/** Wh..QVv
* @return ~] V62^0
* Returns the hasNextPage. @'}2xw[eU
*/ (*P`
publicboolean getHasNextPage(){ Wz=&
0>Mm_
return hasNextPage; T0")Ryu
} g%"SAeG<K
|n)4APX\Q
/** T)sIV5bk
* @param hasNextPage c5$DHT@N"
* The hasNextPage to set. ?wPTe^Qtv
*/ LwRzzgt
publicvoid setHasNextPage(boolean hasNextPage){ } =)u_q
this.hasNextPage = hasNextPage; jvsSP?]n
} \Db;7wh
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/** s7sd(f]=
* @return lAM)X&}0
* Returns the hasPrePage. {Kr}RR*{X
*/ 8)eRm{
publicboolean getHasPrePage(){ fsPNxy"_
return hasPrePage; 8v2Wi.4T
} d;p3cW"
#*.4Jv<R
/** +58^{_k+%
* @param hasPrePage FS&QF@dtgf
* The hasPrePage to set. 1aO(+](;
*/ MbCz*oW
publicvoid setHasPrePage(boolean hasPrePage){ 'l<$H=ZUVG
this.hasPrePage = hasPrePage; 0ZDm[#7z
} KTT!P 4
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/** Ncbe{}<md
* @return Returns the totalPage. O0z-jZ,])
* h ChO
*/ ]}].Aq
publicint getTotalPage(){ M !"Q7>d
return totalPage; ]~dB|WB
} ;kZD>G8
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/** ";(m,if-
* @param totalPage qXq#A&
* The totalPage to set. nbP}a?XC
*/ flqr["czwK
publicvoid setTotalPage(int totalPage){ _ymSo`IvR
this.totalPage = totalPage; cJq{;~
} 6x(b/`VW
> `eo 0
} nt|n[-}
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u c!6?+0h
,B/TqPP
~I>|f
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 3=ME$%f
;:[P/eg
个PageUtil,负责对Page对象进行构造: 2BO H8Mp9
java代码: 4IfkYM
A ;`[va
teDRX13=;
/*Created on 2005-4-14*/ TTj] _R{n
package org.flyware.util.page; 1iR\M4?Frf
!lEV^SQJs
import org.apache.commons.logging.Log; d:&cq8^
import org.apache.commons.logging.LogFactory; *B&i `tq
MJe/ \
/** rM~Mqpk
* @author Joa +gndW
* lp$,`Uz`
*/ )06. dZq\
publicclass PageUtil { [C
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privatestaticfinal Log logger = LogFactory.getLog O&.gc p!
-y&>&D
(PageUtil.class); L-|7
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/** }VH`\g}
* Use the origin page to create a new page A#~CZQY^$
* @param page &{M-<M
* @param totalRecords Gqar5
* @return 9J49s1
*/ u`+kH8#
publicstatic Page createPage(Page page, int /6N!$*8
)J\
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totalRecords){ v%c--cO(S4
return createPage(page.getEveryPage(), ]a~gnz&1
>]\oVG
page.getCurrentPage(), totalRecords); QE;,mC>
} Tt0]G_
SV2\vby}C
/** ~ebm,3?
* the basic page utils not including exception 1RQM-0W,
,8p-EH
handler w~9Y=|YI7
* @param everyPage [9CBTSr
* @param currentPage 4%jSqT@
* @param totalRecords v>Kv!OY:c
* @return page ir)~T0
*/ Vc|QW
publicstatic Page createPage(int everyPage, int Mm"0Ip2"
Z
+}#
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currentPage, int totalRecords){ FO|Eg9l
everyPage = getEveryPage(everyPage); hdH-VR4
currentPage = getCurrentPage(currentPage); ]mO7O+
int beginIndex = getBeginIndex(everyPage, [py/\zkn
@q" #.?>s
currentPage); L|2WTyMU
int totalPage = getTotalPage(everyPage, >Cr'dKZ}
Kzfy0LWM
totalRecords); ^''3}<Ep
boolean hasNextPage = hasNextPage(currentPage, zv\T ;_
t+WUz#i"
totalPage); [*=UH*:'N
boolean hasPrePage = hasPrePage(currentPage); /$ueLa
9;pD0h|
returnnew Page(hasPrePage, hasNextPage, %Zu+=IZ
everyPage, totalPage, `~W ?a
currentPage, 8bEii1EM
0_map z
beginIndex); tj!~7lo
} G-T2b,J
[
@z.HyQ_v
privatestaticint getEveryPage(int everyPage){ s\1c.
return everyPage == 0 ? 10 : everyPage; N^tH&\G\m
} 0',-V2
0(!=N1l
privatestaticint getCurrentPage(int currentPage){ #>\8m+h 9
return currentPage == 0 ? 1 : currentPage; ..ht)Gex
} }&*,!ES*
RT=(vq @
privatestaticint getBeginIndex(int everyPage, int )VR/a
W\yaovAt
currentPage){ =_dqoAF
return(currentPage - 1) * everyPage; %MUwd@,
} (V+iJ_1g{
+D+Rf,D
privatestaticint getTotalPage(int everyPage, int w=75?3c7 F
J{5&L &4
totalRecords){ L[:b\O/p,
int totalPage = 0; V\o&{7!
{5gh.
if(totalRecords % everyPage == 0) ?wS/KEl=O
totalPage = totalRecords / everyPage; |b:91l
else 0V:PRq;v0
totalPage = totalRecords / everyPage + 1 ; 7~Md6.FtM
];o[Yn'>o
return totalPage; Tj*Vk $}0
} t1tZ:4
o@0p
privatestaticboolean hasPrePage(int currentPage){ 4ky@rcD 1
return currentPage == 1 ? false : true; R k).D6
} 9AdA|/WV
g>O
O '}lF
privatestaticboolean hasNextPage(int currentPage, [8Zvs=1
f"G?#dW/1
int totalPage){ aC2\C=ru_
return currentPage == totalPage || totalPage == N-Nq*
GE[J`?E]
0 ? false : true; o=VDO,eS
} -F| C6m!
:Vf :_;
PKM8MYvo
} gNG_,+=!
]RJcY1
m0k~8^L@f
fgSe]q//
k9<P]%
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ]2P*Z6Az
L.@o
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ,2YkQ/>
KDX34Fr1
做法如下: \{ui{8+G
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 nZ 0rxx[V?
U&\8~h
的信息,和一个结果集List: <X_I`
java代码: %kJ_o*"
JW4~Qwx
MdOQEWJ$|
/*Created on 2005-6-13*/ 5L}qL?S`x|
package com.adt.bo; hs"=>(P)
o4"7i 9+g
import java.util.List; M1/Rba Q
q-fxs8+m|
import org.flyware.util.page.Page; 8&"@6/)[
WU
-_Y^
/** 75LIQ!G|=
* @author Joa /i#~#Bn|
*/ X^U)j
N2
publicclass Result { |h; _r&
,5_Hen=PI
private Page page; CN$wlhs
Wb/q&o
private List content; i<*{Z~B
F`$V H^%V
/** s3*h=5bX=
* The default constructor ~EVD NnHEr
*/ jQp7TdvLE$
public Result(){ EVW{!\8[
super(); &ESE?{of)
} %C!u/:.Kv
h98_6Dw(]
/** w>:~Ev]
* The constructor using fields ]e'Ol$3U9=
* "?Eh_Dw
* @param page n\#RI9#\
* @param content ?]'Rz\70
*/ $\|$ekil4
public Result(Page page, List content){ p1
9j
this.page = page; &!uNN|W
this.content = content; <wt#m`Za
} #4ZDY,>Xi#
t UJ m}+=>
/** J1^6p*]GX
* @return Returns the content. 06 kjJ4
*/ lH6zZ8rh
publicList getContent(){ @tY)s
return content; 8$:4~:]/
} >g!a\=-[
I-E}D"F;p[
/** }vRs n-E@
* @return Returns the page. >bia
FK>t
*/ ZqHh$QBD
9
public Page getPage(){ .D^=vuxt~
return page; 7(m4,l+(
} Vj7(6'Hg
f -N:
/** 2t3'"8xJ
* @param content em
* The content to set. ?8g[0/
*/ T#.5F7$u
public void setContent(List content){ l I&%^>
this.content = content; IS`1}i$1%
} {%$eq{~m
OXy>Tlv
/** 85rXm*Df
* @param page }LDH/#
u
* The page to set. sjpcz4|K
*/ Iz/o|o]#
publicvoid setPage(Page page){ 7(;M
this.page = page; )1%l$W
} JG xuB*}
} ?lJm}0>
sgdxr!1?y
w /$4
Rv+S
U^trZ])
/
AFn8=9'^
2. 编写业务逻辑接口,并实现它(UserManager, eHCLENLmB
}Yt/e-Yg%r
UserManagerImpl) {=WTAgP
java代码: qJ=4HlLno
:- B,Q3d
zY\pZG
/*Created on 2005-7-15*/ 1ID0'j$
package com.adt.service; 7mipj]
]sBSLEie
'
import net.sf.hibernate.HibernateException; c:0nOP
) -+u8#
import org.flyware.util.page.Page; ?{W@TY@S
29DYL
import com.adt.bo.Result; gF(aYuk
MA\"JAP/
/** (9hCO-r
* @author Joa (0jT#&#
*/ D"^4X'6
publicinterface UserManager { b4GD}kR
`y5?lS*
public Result listUser(Page page)throws 9ALE6
$2Y'[Dto\
HibernateException; uGIA4CUm
1!,xB]v1Ri
} 3.M<ATe^
:<ye:P1s
%|L+~ =
4LqJ4jo
(|DmYn!
java代码: QR<z%4
hsIC5@s3
X~ n=U4s}O
/*Created on 2005-7-15*/ $]IX11.m
package com.adt.service.impl; 4.|-?qG
j4j %r(
import java.util.List; QXZjsa_|
s`W\`w}
import net.sf.hibernate.HibernateException; CL{R.OA
J-t5kU;L{
import org.flyware.util.page.Page; XXsN)2
import org.flyware.util.page.PageUtil; /QDlm>FM4
vL"U=Q+/eY
import com.adt.bo.Result; }oHA@o5
import com.adt.dao.UserDAO; +L_!$"I
import com.adt.exception.ObjectNotFoundException; %?K1X^52d
import com.adt.service.UserManager; gqR?hZD
M>hHTa?W
/** ,7:_M>-3g
* @author Joa qkB)CY7
*/ t(69gF\"
publicclass UserManagerImpl implements UserManager { <Cc}MDM604
BX :77?9,+
private UserDAO userDAO; c,%9Fh?(
//63?s+
/** et|QW;*L
* @param userDAO The userDAO to set. Ws'OJ1
*/ 40cgsRa|
publicvoid setUserDAO(UserDAO userDAO){ <Z%iP{
this.userDAO = userDAO; ad^7t<a}<
} pp{Za@j
U 2k^X=yl
/* (non-Javadoc) RUHQ]@d#T
* @see com.adt.service.UserManager#listUser \DsP'-t
u/?s_OR
(org.flyware.util.page.Page) ~e<l`rg#
*/ '^f,H1oW
public Result listUser(Page page)throws kfER
D<9FSxl6
HibernateException, ObjectNotFoundException { X;JptF^
int totalRecords = userDAO.getUserCount(); p9]008C89
if(totalRecords == 0) S;DqM;Q
throw new ObjectNotFoundException t,#9i#q#
*:r@-=M3=
("userNotExist");
9?c0cwP?
page = PageUtil.createPage(page, totalRecords); WE""be8
List users = userDAO.getUserByPage(page); #$p&J1
returnnew Result(page, users); 7\*_/[B
} W]Z;=-CBr
HO ,z[6
} nG<_&h
SaKaN#C
}C1&}hZ
JR/:XYS+
4B>N[#-0=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 8[
;Awt: jF
询,接下来编写UserDAO的代码: *^R?*vNs
3. UserDAO 和 UserDAOImpl: qW8sJ=
java代码: ` #Qlr+X
[@"~'fu0
L{y%\:]
/*Created on 2005-7-15*/ u0M[B7Q
package com.adt.dao; 7b7~D +b
B"rV-,n{
import java.util.List; 3!_X FV
2pR+2p`
import org.flyware.util.page.Page; E ,5XX;|
!{'C.sb?~
import net.sf.hibernate.HibernateException; V8`o71p
$X1T!i[.X
/** o^P/ -&T
* @author Joa &%M!!28X:
*/ ];& @T\Rj
publicinterface UserDAO extends BaseDAO { yhzC 9nTH
.U.Knn
publicList getUserByName(String name)throws Pn:L=*
3^m0 k
E
HibernateException; ph*?y
w|$i<OIi)
publicint getUserCount()throws HibernateException; N!R>L{H>
;Fw{p{7<
publicList getUserByPage(Page page)throws r8.R?5F@
[(Z{5gK
HibernateException; iTTUyftHT
lu~<pfg
} ~qFuS933
wrw4Uxq
+T]/4"^M
M7U:UV)
BYj Eo
java代码: 9H^$cM9C
MTm}qx@L
a3t[Tk;
/*Created on 2005-7-15*/ P)7:G?OTx
package com.adt.dao.impl; \@")2o+
9!CD25u
import java.util.List; \0gU)tVZ
zx:Qz
import org.flyware.util.page.Page; dk<) \C"
W=zHD9
import net.sf.hibernate.HibernateException; }<m'Nkz<X
import net.sf.hibernate.Query; #0OW0:Q
XMt)\r.
import com.adt.dao.UserDAO; ?K5S{qG'O
&y\7pAT\
/** ~kHWh8\b:
* @author Joa Sv&_LZ-"P
*/ :SBB3G)|
public class UserDAOImpl extends BaseDAOHibernateImpl ck0K^o v
p./9^S
implements UserDAO { )96tBA%u
,2yIKPWk
/* (non-Javadoc) X*'i1)_h
* @see com.adt.dao.UserDAO#getUserByName 94uAt&&b(
4MM /i}
(java.lang.String) JU>F&g/|
*/ 6*W7I-A
publicList getUserByName(String name)throws "pRi1Y5)l
d8N{sT
HibernateException { TwdY6E3`
String querySentence = "FROM user in class Hl"^E*9x
eMHBY6<~=
com.adt.po.User WHERE user.name=:name"; $U*b;'o
Query query = getSession().createQuery qDlh6W?}k
V -X*e
(querySentence); \mp2LICQg
query.setParameter("name", name); }BFX7X
return query.list(); 7+'&(^c
} zCz"[9k
HpCTQ\H
/* (non-Javadoc) 2!kb?
* @see com.adt.dao.UserDAO#getUserCount() h^ o@=%b
*/ 5rX_85 ]
publicint getUserCount()throws HibernateException { l&JV.}qGB8
int count = 0; 8'<RPU}M
String querySentence = "SELECT count(*) FROM g#*LJ`1
4:Ton
user in class com.adt.po.User"; K;L6<a A#
Query query = getSession().createQuery !c2<-3e
O su 75@3
(querySentence); Rz03he
count = ((Integer)query.iterate().next Y|X!da/
;Q.'u
()).intValue(); Xtk3~@
return count; h/s8".\
} td!YwN*
0bz':M#k &
/* (non-Javadoc) >~}}*yp
* @see com.adt.dao.UserDAO#getUserByPage 3[*x'"Q;H
5K#<VU*:
(org.flyware.util.page.Page) JHJIjYG>P
*/ P*!~Z*"
publicList getUserByPage(Page page)throws ^ }k qAmr
;;>G}pG
HibernateException { G=(ja?d
String querySentence = "FROM user in class QHHj.ZY
3UgPVCT
com.adt.po.User"; <lN=<9
Query query = getSession().createQuery x'iBEm
JT cE{i
(querySentence); Ewq7oq5:
query.setFirstResult(page.getBeginIndex()) w+][L||4c
.setMaxResults(page.getEveryPage()); D b&=
N
return query.list(); oK@_
} v;.w*x8Jw
?QRoSQ6
} q,>-4Cm
@v~<E?Un
w,zm$s ^
ecdM+kP
&=[N{N?(
至此,一个完整的分页程序完成。前台的只需要调用 U6IvN@
g
*r/o
\pyH
userManager.listUser(page)即可得到一个Page对象和结果集对象 rD!UP1Nb
_m@+d>f_
的综合体,而传入的参数page对象则可以由前台传入,如果用 ALi3JU
&BOG&ot
webwork,甚至可以直接在配置文件中指定。 FIN0~
8
LZ4Z]!V
下面给出一个webwork调用示例: z{(c-7*
java代码: h[& \OD,P
5?HoCz]l
@$7l
/*Created on 2005-6-17*/ .2f0e[J
package com.adt.action.user; y{9<>28
z)fg>?AGr
import java.util.List;
f)#nXTXeC
7hAc6M$h;
import org.apache.commons.logging.Log; a=r^?q'/
import org.apache.commons.logging.LogFactory; 5
8n(fdE
import org.flyware.util.page.Page; 28,g 'k!
' p!\[*e
import com.adt.bo.Result; df8aM<&m3
import com.adt.service.UserService; vq8&IL
import com.opensymphony.xwork.Action; X8~gLdv8
I,7n-G_'
/** oLc
* @author Joa v"V?
*/ pKhV<MFB
publicclass ListUser implementsAction{ n_S)9C'=
pP*`b<|
privatestaticfinal Log logger = LogFactory.getLog %0lJ(hm
yL"pzD`[H
(ListUser.class); 9V?:!%J
7NP
Ny
private UserService userService; mApl}I
q/dja
private Page page; BE,H`G #h
Nrfj[I
privateList users; _<7e5VR
;#n+$Q#:
/* q/3 )yG6s
* (non-Javadoc) R zn%!d^$>
* *6QmYq6c<
* @see com.opensymphony.xwork.Action#execute() ^ jT1q_0
*/ Wu
U_RE
publicString execute()throwsException{ ='vkd=`Si
Result result = userService.listUser(page); P7y.:%DGD0
page = result.getPage(); <lf6gb
users = result.getContent(); \Z/#s;c,4
return SUCCESS; i1-wzI
} !--A"
r=:o$e
/** "dFuQB
* @return Returns the page. zf?U q
*/ a{!
8T
public Page getPage(){ 0RkiD8U5
return page; =Y<RG"]a&J
} nhI1`l&
7gP8K`w?[
/** PP!}w
* @return Returns the users. >o8N@`@VK-
*/ 8\9s,W:5
publicList getUsers(){ c@)}zcw*
return users; l ArDOFl]x
} YY9Ub
;eiqzdP
/** )NCSO b
* @param page [LrA_N
* The page to set. 50Y^##]&
*/ >n6yKcjY]
publicvoid setPage(Page page){ XE.Y?{,R$
this.page = page; :yE7jXB
} v@;!fBUt
i~;Yrc%AEX
/** #hP&;HZ2>"
* @param users Bw8&Amxx:
* The users to set. c(!8L\69V}
*/ [XDr-5Dm
publicvoid setUsers(List users){ D$PR<>=y
this.users = users; [;8vO=Z
} D_-<V,3t
@Sd l~'"
/** <o.?T*Q9
* @param userService HzD=F3\r|
* The userService to set. BZ-)XF'4
*/ xH/Pw?^
publicvoid setUserService(UserService userService){ E-XFW]I
this.userService = userService; UJ1Ecob
} 1)N{!w`
} k{d)'\FM
BuIly&qbm<
r4(Cb_
ju%t'u\'
P},d`4Ty@
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, !>gu#Q{\-
4KCJ(<p|
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 Ceco^Mw
_M9-n
么只需要: Lyj0$wbH`
java代码: ^VAvQ(b!:i
a<ztA:xt|1
7n*[r*$
<?xml version="1.0"?> of>"qrdZ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork RmcQGQ
K^fH:pV
1.0//EN" "http://www.opensymphony.com/xwork/xwork- }ikJa
SB\T
iH/
1.0.dtd"> %?~`'vYoi
{'R\C5:D7
<xwork> OJ Y_u[
2Ed
<package name="user" extends="webwork- X__>r ?oJ
6pi^ rpo
interceptors"> x0 dO^D
oiY&O]}
<!-- The default interceptor stack name A3=$I&!%
35X4]
t
--> >7^i>si
<default-interceptor-ref [r"`rBw
~Q/G_^U:
name="myDefaultWebStack"/> BO3%p
Q'n]+%YN
<action name="listUser" !mtq?LV
e-.s63hm
class="com.adt.action.user.ListUser"> WPzq?yK
<param 7)y9%-}
JSOgq/\
name="page.everyPage">10</param> 7TW</g(
<result fR6.:7&
(@y te
name="success">/user/user_list.jsp</result> :Kt'Fm,s?
</action> IU*w'a
hRWRXC9
</package> /o)o7$6Q
KqH_?r`
</xwork> 6s$jt-bH
/y<nAGtD&
K@UQ O
TUaW'
E")g1xGaK
O5?Gv??@
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 nD8CP[bRo
ca{u"n
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。 <#r/4a"V
F:o<E 42
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Qso"jYl<
hn@T ]k
D^~G(m;-
yd-Kg zm8n
1VD8y_tC
我写的一个用于分页的类,用了泛型了,hoho F3L'f2yBG
#& 5}
java代码: M((]> *g
}#h >*+Q
h*JzJ0X
package com.intokr.util; Ct)l0J\XH
XA*sBf
import java.util.List; Bh\>2]~@a
4tb y N
/** aN/0'V|&ym
* 用于分页的类<br> dmkd.aP4
* 可以用于传递查询的结果也可以用于传送查询的参数<br> WLe9m02r
* 7Ib/Cm0d|
* @version 0.01 }}g.L|
* @author cheng _FRwaFVJ3
*/ foOwJ }JU
public class Paginator<E> { 8.'[>VzBL
privateint count = 0; // 总记录数 T.57Okp
privateint p = 1; // 页编号 g,0u_$U
privateint num = 20; // 每页的记录数 JGB 9Z
privateList<E> results = null; // 结果 1Y-m=~J7
8a;I,DK=j
/** w>q:&Q
* 结果总数 qf7oG0
*/ .1&~@e%=-
publicint getCount(){ }zkMo?
return count; *yx&4)Or
} *<[Nvk^
>O:31Uk
publicvoid setCount(int count){ }95;qyQ$
this.count = count; E_[)z%&n2
} *61+Fzr
q*^F"D:?k
/** [=
GVK
* 本结果所在的页码,从1开始 2KUm(B.I
* 38[k o3
* @return Returns the pageNo. +@QN)ZwVy
*/ d0;$k,
publicint getP(){ p..O;_U
return p; ygvX}q
} 0(Hhb#WDh\
>Y h7By
/** n8!qz:z/
* if(p<=0) p=1 ^zMME*G
* ,.cNs5[t
* @param p Oh\+cvbG
*/ }nQni?
publicvoid setP(int p){ y~w -z4
if(p <= 0) q:y_#r"_y
p = 1; >z`^Q[
this.p = p; RO([R=.`/
} Z]1=nSv
eu]t.Co[X
/** Nf#8V|
* 每页记录数量 scffWqEo
*/ 4TBK:Vm5
publicint getNum(){ ;}tEU'&
return num; #9{9T"ed
} 9'qU4I
YSvZ7G(m>
/** '%u7XuU-]
* if(num<1) num=1 C;T:'Uws
*/ =*AAXNs@3
publicvoid setNum(int num){ y}fF<qih'>
if(num < 1) yN0!uzdW*
num = 1; AX Y.80+
this.num = num; T4O H,^J
} =
}&@XRLJ
]y4(WG;:
/** S~8w- lG!
* 获得总页数 8fn7!
*/ 1|?8g2Vf
publicint getPageNum(){ urlwn*!^s
return(count - 1) / num + 1; ]kN<N0;\d
} a cSm+t
6N%fJ
/** t3#My2 =
* 获得本页的开始编号,为 (p-1)*num+1 0g-bApxz*&
*/ ]vyu!
publicint getStart(){ Br}&
return(p - 1) * num + 1; t8"*jt
} dFd^@b
fQ\nK H~
/** x}g5
* @return Returns the results. D# $Fj
*/ BZ] 6W/0
publicList<E> getResults(){ !besMZ
return results; K+0&~XU
} _f~(g1sE
j.3#rxq
public void setResults(List<E> results){ %uuh+@/&yz
this.results = results; `5[$ 8;
} d},IQ,Az:Z
Vvth,
public String toString(){ }~?B>vZS
StringBuilder buff = new StringBuilder u,zA^%
6m.ChlO/
(); *4i)aj
buff.append("{"); O8;`6r
buff.append("count:").append(count); A`=;yD
buff.append(",p:").append(p); v^Eg ,&(
buff.append(",nump:").append(num); jRswGMx
buff.append(",results:").append &C~R*
N1lhlw6
(results); b8?qYm
buff.append("}"); vyME
return buff.toString(); F{#m~4O
} LQ,RQ~!
dLtSa\2Hn
} +E8Itb,
4"OUmh9LHB
Yy 4EM