Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Dk}txw}#
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 L"}2Y3
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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 bLO^5` 6
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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 ygxaT"3"=
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分页支持类: 5yf`3vV|3@
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java代码: UZo[]$"Q`
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package com.javaeye.common.util; Hqb-)8 ~
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import java.util.List; VVc-Dx
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publicclass PaginationSupport { d V3R)
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publicfinalstaticint PAGESIZE = 30; X + B=?|M
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privateint pageSize = PAGESIZE; AZnFOS
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privateList items; &_3o 1<
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privateint totalCount; Ca3
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privateint[] indexes = newint[0]; *s!T$oc
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privateint startIndex = 0; DK<}q1xi
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public PaginationSupport(List items, int !
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totalCount){ {%z5^o1)
setPageSize(PAGESIZE); 7/bF04~%
setTotalCount(totalCount); la{o<||Aq
setItems(items); @XH@i+{B
setStartIndex(0); Gk)6ljL
} g?>
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public PaginationSupport(List items, int KXcE@q9
!{XVaQ?x
totalCount, int startIndex){ Cil1wFBb
setPageSize(PAGESIZE); F#|mN0op
setTotalCount(totalCount); xS_tB)C
setItems(items); ;eP.B/N
setStartIndex(startIndex); nDXy$f8
} ?d)FYB
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public PaginationSupport(List items, int wfM|3GS+.
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totalCount, int pageSize, int startIndex){ [UB]vPXm$
setPageSize(pageSize); h[gKyxZ/t
setTotalCount(totalCount); &usum~@
setItems(items); VB~Do?]*k%
setStartIndex(startIndex); 3MoVIf1
} ?aU-Y_pMe
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publicList getItems(){ 2~@Cj@P]
return items; df9$k0Fx
} xUIH,Fp-9
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publicvoid setItems(List items){ $lF\FC
this.items = items; VpB+|%@p
} *m&(h@l
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publicint getPageSize(){ $wqi^q*)
return pageSize; }Q_ }c9?
} ;uqi
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publicvoid setPageSize(int pageSize){ K}Lu1:~
this.pageSize = pageSize; (E \lLlN
} S~{}jvc
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publicint getTotalCount(){ NJ(H$tB@
return totalCount; dhi9=Co;
} <X]dR
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publicvoid setTotalCount(int totalCount){ }?Tz=hP
if(totalCount > 0){ A )xfO-
this.totalCount = totalCount; CoM?cS S
int count = totalCount / 9j$ J}=y
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pageSize; Yu|L6#[E
if(totalCount % pageSize > 0) Y NG S"3F
count++; 8&v%>wxR@
indexes = newint[count]; {Pe+d3Eoo
for(int i = 0; i < count; i++){ bYy7Ul6]
indexes = pageSize * Bmi9U
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i; ;})so
} &MGM9
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}else{ k#<Y2FJa
this.totalCount = 0; CK1gzIg>
} /XwwB
} nY_+V{F
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publicint[] getIndexes(){
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return indexes; t<znz6
} 5}`e"X
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publicvoid setIndexes(int[] indexes){ jNP%BNd1f
this.indexes = indexes; tnC,1HV0[
} {_X&{dZLX
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publicint getStartIndex(){ $~:|Vj5iZ\
return startIndex; e",0Er FT
} x$24Nc1a'
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publicvoid setStartIndex(int startIndex){ X&.LX
if(totalCount <= 0) hi9@U]H#
this.startIndex = 0; i}Cy q
elseif(startIndex >= totalCount) R TeG\U
this.startIndex = indexes ]s~%1bd
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[indexes.length - 1]; Xldz&&@
elseif(startIndex < 0) yUu+68Z6
this.startIndex = 0; 4 UnN~
else{ ehQ~+x
this.startIndex = indexes @'FO M
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[startIndex / pageSize]; IJofbuzw:
} a9TKp$LP`
} sQ%gf
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publicint getNextIndex(){ n;*W#c
int nextIndex = getStartIndex() + 3+iQct[
s
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pageSize; w-?Cg8bq<
if(nextIndex >= totalCount) ^I6GH?19>e
return getStartIndex(); aKC3vR0
else +zSdP2s
return nextIndex; 6#1:2ZHKG
} jW_FaPW(p
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publicint getPreviousIndex(){ |=ljN7]!
int previousIndex = getStartIndex() - nWv6I&
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pageSize; uzWz+atH
if(previousIndex < 0) G>0hi1
return0; [USE&_RN
else o'p[G]NQ1o
return previousIndex; &!O~ f
} ^0T[V-PgiD
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} [Xo}CU
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抽象业务类 /&G )IY]g
java代码: Fx' E"d
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/** /S&8%fb
* Created on 2005-7-12 K!_''Fg
*/ $#d.@JWi
package com.javaeye.common.business; L=5Fvm
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import java.io.Serializable; y7Sj^muBY
import java.util.List; jd?NN:7
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import org.hibernate.Criteria; x>~.cey
import org.hibernate.HibernateException; =CjN=FM
import org.hibernate.Session; nwPU{4#l<
import org.hibernate.criterion.DetachedCriteria; UvM_~qo
import org.hibernate.criterion.Projections; (T Fo]c
import ex-W{k$
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org.springframework.orm.hibernate3.HibernateCallback; nW`EBs
import TGu]6NzyZ
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org.springframework.orm.hibernate3.support.HibernateDaoS 9EKc{1
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upport; `d.4L.],
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import com.javaeye.common.util.PaginationSupport; mY,t]#^m7
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public abstract class AbstractManager extends keL!;q|r-)
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HibernateDaoSupport { I6Mr[#*
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privateboolean cacheQueries = false; mL[Y{t#N
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privateString queryCacheRegion; F otHITw[
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publicvoid setCacheQueries(boolean 6b9&V`
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cacheQueries){ A J"/T+g_
this.cacheQueries = cacheQueries; N"rZK/@}
} {Qr0pjE7R
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publicvoid setQueryCacheRegion(String LX_{39?<{
;(,1pi7|
queryCacheRegion){ ZP^7`q)6
this.queryCacheRegion = ;IX*4E'4s
Z* L{;
queryCacheRegion; H{nYZOf/
} UAq%Y8KA
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publicvoid save(finalObject entity){ J}J7A5P
getHibernateTemplate().save(entity); p7kH"j{xD
} yCOIv!/zy
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publicvoid persist(finalObject entity){ VPqMbr"L[
getHibernateTemplate().save(entity); zS+_6s
} R x.]m0
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publicvoid update(finalObject entity){ K JX@?1"
getHibernateTemplate().update(entity); e<[0H 8
} OGqsQ
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publicvoid delete(finalObject entity){ v9R"dc]0h
getHibernateTemplate().delete(entity); DR w;.it2
} -*r]9f6x
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publicObject load(finalClass entity, j}$Up7pW
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finalSerializable id){ ~M4@hG!
return getHibernateTemplate().load uepL"%.@7|
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(entity, id); ]~A<Q{
} 81<0B@E
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publicObject get(finalClass entity, hpVu
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finalSerializable id){ )Mj
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return getHibernateTemplate().get ';0NWFP
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(entity, id); 3Ta<7tEM
} Cq-#|+zr
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publicList findAll(finalClass entity){ }lzN)e
return getHibernateTemplate().find("from ]9}T)Df'
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" + entity.getName()); Y?>us
} A,)G$yT\
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publicList findByNamedQuery(finalString "Nn+Zw43
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namedQuery){ ^3:DeZf!u
return getHibernateTemplate |rbl sL2?Z
ax)j$
().findByNamedQuery(namedQuery); +#d}3^_]
} 6b8@6;&LI
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publicList findByNamedQuery(finalString query, X)TUKt
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finalObject parameter){ ToB^/
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return getHibernateTemplate 5@{+V!o,
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().findByNamedQuery(query, parameter); +.b@rU6H
} )5Bkm{v3
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publicList findByNamedQuery(finalString query, {)vue0
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finalObject[] parameters){ +L$,jZqS
return getHibernateTemplate Kx;DmwX-
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().findByNamedQuery(query, parameters); oe5.tkc
} 'C9H6)Zq)
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publicList find(finalString query){ gAY%VFBP0
return getHibernateTemplate().find u8wZ2j4S
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(query); dWI.t1`i
} $.z~bmH"D
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publicList find(finalString query, finalObject -|DSfI#j
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parameter){ f~.w2Cna
return getHibernateTemplate().find /~LXY<-(
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(query, parameter); _uO#0
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} |@-%x.y
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public PaginationSupport findPageByCriteria / h6(!-"
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(final DetachedCriteria detachedCriteria){ &E{5k{Y
return findPageByCriteria 6rnehv!p
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); |-zwl8E
} sX&M+'h
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public PaginationSupport findPageByCriteria :`Kr|3bQ
@HfWAFT
(final DetachedCriteria detachedCriteria, finalint I~R<}volu
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startIndex){ p0.?R
return findPageByCriteria n(Up?_
$l&&y?()
(detachedCriteria, PaginationSupport.PAGESIZE, tH:K6^oR
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startIndex); ndm19M8Y|
}
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public PaginationSupport findPageByCriteria 6bg+U`&g
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(final DetachedCriteria detachedCriteria, finalint $p4aNC
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pageSize, OvPy+I
finalint startIndex){ V=|^r?
return(PaginationSupport) 8-5a*vV,>
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getHibernateTemplate().execute(new HibernateCallback(){ ,h2q37
publicObject doInHibernate We]X+>BlO
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(Session session)throws HibernateException { 13Z6dhZu
Criteria criteria = ;f-|rC_"
W4CI=94
detachedCriteria.getExecutableCriteria(session); $/C<^}A
int totalCount = 71tMX[x
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((Integer) criteria.setProjection(Projections.rowCount h6x+.}}
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()).uniqueResult()).intValue(); EGwY|+3
criteria.setProjection 7atYWz~yG
.;tO;j|6
(null); yj$S?B Ee
List items = p _e-u-
q
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criteria.setFirstResult(startIndex).setMaxResults hkgPC-
+&\TdvNI4
(pageSize).list(); l@*/1O)v
PaginationSupport ps = J'O`3!Oy/
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new PaginationSupport(items, totalCount, pageSize, i,")U)b
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startIndex); p 8"(z@T
return ps; "|DR"rr'j
} eq/5$b(
}, true); [Pp#l*
} !E_uQ?/w]Z
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public List findAllByCriteria(final oz5o=gt7
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DetachedCriteria detachedCriteria){ YLd
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return(List) getHibernateTemplate d L%E0o
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().execute(new HibernateCallback(){ \ b9,>
publicObject doInHibernate na']{a1K
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(Session session)throws HibernateException { `A
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Criteria criteria = UxicqkX
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detachedCriteria.getExecutableCriteria(session); Dlj=$25
return criteria.list(); H[N&Wiq/|
} ^z&xy41#B
}, true); iL 4SL}P
} J+*rjdI
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public int getCountByCriteria(final L)nVNY@Mc
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DetachedCriteria detachedCriteria){ GPx S.&
Integer count = (Integer) |>3a9]
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getHibernateTemplate().execute(new HibernateCallback(){ Rg[e~##
publicObject doInHibernate >!)VkDAG
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(Session session)throws HibernateException { jZ
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Criteria criteria = aJ)5 DlfLR
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detachedCriteria.getExecutableCriteria(session); @B9|{[P
return x>8f#B\Mr
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criteria.setProjection(Projections.rowCount Mqh~ 5NM
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()).uniqueResult(); ^LU[{HZV
} k13/yiv
}, true); +~fu-%,k
return count.intValue(); $m=z87hX
} aq5<Ks `r
} E7eVg*Cvi
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用户在web层构造查询条件detachedCriteria,和可选的 CQ( @7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 kxn;;
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PaginationSupport的实例ps。 ?*s!&-KI
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ps.getItems()得到已分页好的结果集 2@&|hd=-
ps.getIndexes()得到分页索引的数组 nIi_4=Z
ps.getTotalCount()得到总结果数 QNJG}Upl
ps.getStartIndex()当前分页索引 #wjBMR%
ps.getNextIndex()下一页索引 .FXQ,7mZ-
ps.getPreviousIndex()上一页索引 f.P( {PN
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 *tO<wp&
B)Q'a3d#
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 a,4g`?
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:;(W_
一下代码重构了。 `P5"5N\h
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我把原本我的做法也提供出来供大家讨论吧: l46F3C|
0/gcSW
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首先,为了实现分页查询,我封装了一个Page类: ;Pa(nUE@
java代码: *=7[Ip<X
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/*Created on 2005-4-14*/ )g --=w3
package org.flyware.util.page; aOD"z7}U
piG1&*
/** h[8y$.YsC
* @author Joa #CS>A#Lk
* lX4p'R-h
*/ 2bJFlxEU
publicclass Page { c'B"Onu@m*
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/** imply if the page has previous page */ =z3jFaZ
privateboolean hasPrePage; op-#Ig$#
b
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/** imply if the page has next page */ (Lo2fY5
privateboolean hasNextPage; 709eLhXrH
=R'v]SXj
/** the number of every page */ JB(;[# '~
privateint everyPage; R,\
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/** the total page number */ O%&@WrFq
privateint totalPage; dvD<>{U,8
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/** the number of current page */ WNb$2q=
privateint currentPage; RrHnDO'
EDo@J2A
/** the begin index of the records by the current @(cS8%wK
xB(:d'1|
query */ 8[C6LG
privateint beginIndex; ,2TqzU;
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/** The default constructor */ &FrB6y
public Page(){ 9^ r
C'._}\nX
} 1955(:I
JLu0;XVK
/** construct the page by everyPage Ln_l>X6j51
* @param everyPage j1F+,
* */ %-l:_A
public Page(int everyPage){
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this.everyPage = everyPage; +_eb*Z`5o
} FZnHG;af
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/** The whole constructor */ zcKC5vqb
public Page(boolean hasPrePage, boolean hasNextPage, ElXe=5L\#
6
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int everyPage, int totalPage, 8q3TeMYV
int currentPage, int beginIndex){ 5Mr;6
]I<
this.hasPrePage = hasPrePage; {_Qxe1^g
this.hasNextPage = hasNextPage; / D ]B
this.everyPage = everyPage; 2]9<%-=S
this.totalPage = totalPage; ikhX5
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this.currentPage = currentPage; ku;nVV
this.beginIndex = beginIndex; l,u{:JC
} X=pt}j,QrP
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/** Yd;r8rN
* @return q=Yerp3~
* Returns the beginIndex. AfN
*/ } qv-lO
publicint getBeginIndex(){ XyphQ}\u
return beginIndex; E ZKz-}
} ~5uNw*H
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/** ]&U| d
* @param beginIndex Noxz kpMF
* The beginIndex to set. &t/<yq}{
*/ 9yo[T(8
publicvoid setBeginIndex(int beginIndex){ 5vi#ItN}|
this.beginIndex = beginIndex; 0juIkN#
} )m8>w6"
rp#*uV9;
/** X&s\_jQ
* @return a{HgIQg_>R
* Returns the currentPage. (eG]Cp@
*/ R6Mxdm2P}
publicint getCurrentPage(){ W 'a~pB1I
return currentPage; $D s]\j*
} 8.Ef 5-m
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/** m=\eL~h
* @param currentPage ev%t5NZ
* The currentPage to set. MD4 j~q\g
*/ 1IQOl
publicvoid setCurrentPage(int currentPage){ y/I~x+y
this.currentPage = currentPage; q;../h]Ne
} J+ZdZa}Ob
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/** Q(5:~**I
* @return xO<-<sRA
* Returns the everyPage. 0nz@O^*g(
*/ [l%fL9
publicint getEveryPage(){ /B@%pq
return everyPage; ~wf~bzs
} N E2sD
@b*T4hwA.
/** uAS8F=9xP
* @param everyPage >?W;>EUH
* The everyPage to set. Xb@z7X#O!
*/ FP9<E93br
publicvoid setEveryPage(int everyPage){ uU(G_E ?
this.everyPage = everyPage; :.[5('
} |vDoqlW
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/** ENXW#{N.v
* @return !BQ ELB$0
* Returns the hasNextPage. n+\Cw`'<H
*/ 1X"H6j[w
publicboolean getHasNextPage(){ ^$+f3Z'
return hasNextPage; |@L &yg,x
} *_/eAi/WG
@EP{VV
/** RQS:h]?:l
* @param hasNextPage m)|.:sj
* The hasNextPage to set. ZYR,8 y
*/ Hv gK_'
publicvoid setHasNextPage(boolean hasNextPage){ zHoO?tGf
this.hasNextPage = hasNextPage; {iIg 4PzrU
} 7! b)'W?
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/** -?w v}o
* @return %Di7u- x
* Returns the hasPrePage. ds$ \vSd
*/ :KV,:13`D
publicboolean getHasPrePage(){ 'x,GI\;?
return hasPrePage; zGL<m0C
} 2mG&@E
hXQg=Sj
/** ?^48Zq6wM
* @param hasPrePage >RL6Jbo|
* The hasPrePage to set. `k{ ff
*/ QV'3O|
publicvoid setHasPrePage(boolean hasPrePage){ :Bv&)RK
this.hasPrePage = hasPrePage; OU.9 #|q U
} j&[3Be'pQ
J'&B:PZObB
/** llaZP(pJ
* @return Returns the totalPage. K!-&Zv
* %YvSHh;c
*/ *4hOCQ[
publicint getTotalPage(){ \p@nH%@v
return totalPage; iVpA@p
} g?A5'o&Yu
Sp`fh7d.(
/** $~G0#JL
* @param totalPage h*\TCl)
* The totalPage to set. ^=izqh5S
*/ }lC64;yo
publicvoid setTotalPage(int totalPage){ g"Q}h
this.totalPage = totalPage; 3h[:0W!C]
} 'x45E.wYw
{GX
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} =JbdsYI(
:L [YmZ
)kL`&+#>
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9-a2L JI
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 im4e!gRE
#zSi/r/=1
个PageUtil,负责对Page对象进行构造: 9#s95RO
java代码: >Oi2gPA
x<{;1F,k3
&w;^m/zP3
/*Created on 2005-4-14*/ ND e[2
package org.flyware.util.page; @ yg|OA}
Z}LOy^TL
import org.apache.commons.logging.Log; @\6nXf
import org.apache.commons.logging.LogFactory; %7C%`)T]
nv_m!JG7
/** STXqq[+Rf
* @author Joa gf3u0' $
* ^T}}4I_Y
*/ 8tT&BmT
publicclass PageUtil { GLaZN4`
c>u>Pi;Z
privatestaticfinal Log logger = LogFactory.getLog eHR&N.2
wv7p,9Z[
(PageUtil.class); OXIu>jF
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/** >ggk>s|
* Use the origin page to create a new page a9?
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* @param page &e HM#as
* @param totalRecords tyn?o
* @return qL%.5OCn(
*/ c#\ah}]Vo
publicstatic Page createPage(Page page, int oRT
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totalRecords){ )8x:x7?
return createPage(page.getEveryPage(), .y %pGi
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page.getCurrentPage(), totalRecords); {.aK{
V
} W2F+^
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/** 0okO+QU,a
* the basic page utils not including exception ;B|^2i1Wi
]/ZA/:Oa+
handler e9z$+h
* @param everyPage G!!-+n<
* @param currentPage hapB! ~M?
* @param totalRecords TdNuD V
* @return page Xb(CH#*{z
*/ w&wA >q>&
publicstatic Page createPage(int everyPage, int {(m+M
xUiWiOihr6
currentPage, int totalRecords){ 097Fvt=#
everyPage = getEveryPage(everyPage); #L@} .Giz
currentPage = getCurrentPage(currentPage); pW*{Mx
int beginIndex = getBeginIndex(everyPage, vi[#?;pkF
1R'u v4e
currentPage); >G-8FL
int totalPage = getTotalPage(everyPage, mHK@(D7X
#/n|@z'
totalRecords); cS"f
boolean hasNextPage = hasNextPage(currentPage, iXUWIgr
nV!2Dfd
totalPage); Xk{!' 0
boolean hasPrePage = hasPrePage(currentPage); Z-^uM`],G
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returnnew Page(hasPrePage, hasNextPage, ]~j_N^oZ1X
everyPage, totalPage, SWNU1x{,c\
currentPage, 936Ff*%(l
9]]!8_0=r
beginIndex); 7af?E)}v
} Y=P9:unG
Mv/IMO0rR
privatestaticint getEveryPage(int everyPage){ 90
return everyPage == 0 ? 10 : everyPage; 1KeJd&e
} egZyng
pB
V;>9&'Z3
privatestaticint getCurrentPage(int currentPage){ L
Yh@ u1p
return currentPage == 0 ? 1 : currentPage; _-4n~(
} A|p@\3P*A
}Kvh`@CiJ
privatestaticint getBeginIndex(int everyPage, int Nd]0ta
XAjd
%Xv<
currentPage){ A5CdLwk
return(currentPage - 1) * everyPage; i&A{L}eCr:
} .+{nA}Bc
EpRXjz
privatestaticint getTotalPage(int everyPage, int ~/^y.SsWM
mV6#!_"
totalRecords){ a(PjcQ4dY
int totalPage = 0; ePV-yy
G*kE~s9R
if(totalRecords % everyPage == 0) 07.nq;/R
totalPage = totalRecords / everyPage; ,|e} Y
[
else j4E H2v
totalPage = totalRecords / everyPage + 1 ; C/mg46
v2W
@MNl*~'$.[
return totalPage; [MV`pF)x
} e%PCe9
mDb-=[W5
privatestaticboolean hasPrePage(int currentPage){ Jz~+J*r;]A
return currentPage == 1 ? false : true; kmZ.U>#
} I["F+kt^^
e(?:g@]-r
privatestaticboolean hasNextPage(int currentPage, 6?53q e
GLo\q:5A
int totalPage){ 0L!er%GM
return currentPage == totalPage || totalPage == 4fu'QZ(}
5Waw?1GL
0 ? false : true; Wr]O
} 4a\n4KO X
xCR;
K]!
]XmQ]Yit
} whV&qe;sw
gsW=3m&`
cDfx)sL
LiiK3!^i
4st~3,lR$
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。 t{+M|Y
o)0C-yO0qf
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 }BA9Ka#%
]b}B~jD
做法如下: CkRyzF
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 [?;`x&y~y
TcR=GR*cJ
的信息,和一个结果集List: X7e>Z)l
java代码: qIB>6bv#x
x$~3$E
U'rr?,RML
/*Created on 2005-6-13*/ A|2 <A
!
package com.adt.bo; Q}WL/X5
d/l,C4p
import java.util.List; 6,B-:{{e"
?lF mXZy`
import org.flyware.util.page.Page; \|v `l{
V@B7P{gH
/** `Ac:f5a
* @author Joa +T-@5v[
*/ YKc>6)j
publicclass Result { R78!x*U}
3 t/ R 2M
private Page page; 6hp{,8|D"m
I|H,)!Z
private List content; 7 n\mj\
Y
[4vRzc
/** 4S'[\ZJO
* The default constructor E3y6c)<
*/ VK9Q?nu
public Result(){ yb69Q#V2
super(); k69kv9v@J
} ~D*b3K8X
<'W=]IAV
/** v}Z9+ yRC2
* The constructor using fields [w,(EE
* +yGY785b
* @param page <} &7 a s
* @param content BlL|s=dlQV
*/ w2k<)3 g~
public Result(Page page, List content){ -<xyC8$^$
this.page = page; :MK=h;5Z
this.content = content; B#1:Y;Z
} oE$hqd s
hXNH"0VCV
/** RV}GK
L>gn
* @return Returns the content. ;{Xy`{Cg!
*/ F{;;
:
publicList getContent(){ Ky *DfQA
return content; 4ffU;6~l'
} ~xw5\Y^
,`yyR:F
/** 4b]_
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* @return Returns the page. I|Z/`9T
*/ Np$z%ewK.
public Page getPage(){
^,+nef?=
return page; 6nc0=~='$
} FW_G\W.
Vz'HM$
/** UkZ\cc}aC/
* @param content z/weit
* The content to set. _$8{;1$T?
*/ 8qN"3 Et
public void setContent(List content){
C>4UbU
this.content = content; k5wi'
} !5&%\NSv
s1{[{L3
/** un6cD$cHr
* @param page `%oIRuYG]j
* The page to set. =rEA:Q`~w
*/ <.}Ua(
publicvoid setPage(Page page){ H/^B.5RYE>
this.page = page; BMdSf(l
} 6ga5^6W
} T(JuL<PB
oKRFd_r +
alc]
DKTD Z*
%MbyKz:X
2. 编写业务逻辑接口,并实现它(UserManager, t-!m
vx9Z
pr$~8e=c
UserManagerImpl) D;jK/2
java代码: #Mg lHQO+
U-eI\Lu
3?@?-q2g
/*Created on 2005-7-15*/ 7lR<@$q
package com.adt.service; Ew]<jF|.#
c yP,[?N
import net.sf.hibernate.HibernateException; H'Ln
P>@n#
g,=^'D
import org.flyware.util.page.Page; b~*i91)\
F?cq'd
import com.adt.bo.Result; PyFj@n
'PpZ/ry$
/** L%XXf3;c
* @author Joa ` 5#hjLe
*/ ei|cD[
NY
publicinterface UserManager { \DS^i`o)rY
MxTmWsaW
public Result listUser(Page page)throws ]-:1se
781]THY=
HibernateException; vOe0}cR
=*O=E@]
} f TO+ZTRqf
E M Q4yK
dMV=jJ%Y
bK4&=#Zh
x,\!DLq:p
java代码: R*bmu
B)6#Lp3
t.)AggXj#
/*Created on 2005-7-15*/ 3fp> 4;ym'
package com.adt.service.impl; m2 O&2[g
UOt8Q0)}
import java.util.List; '_0
5ITq?%{M
import net.sf.hibernate.HibernateException; ^)0 9OV+hF
5kn+
>{jh`
import org.flyware.util.page.Page; |1Hc&
import org.flyware.util.page.PageUtil; 0%
+'
8_a3'o%5
import com.adt.bo.Result; `%=<R-/#7S
import com.adt.dao.UserDAO; iP#=:HZu;
import com.adt.exception.ObjectNotFoundException; J{tVa(.
import com.adt.service.UserManager; qjAh6Q/E`
*ik/p
/** #tDW!Xv?
* @author Joa [;^,CD|P
*/ :u/mTZDi
publicclass UserManagerImpl implements UserManager { 41yOXy ;~l
\|t{e8}
private UserDAO userDAO; xA #H0?a]
k':s =IXW
/** 6t7fa<
* @param userDAO The userDAO to set. vq>l>as9O
*/ b\giJ1NJB
publicvoid setUserDAO(UserDAO userDAO){ R=M!e<'
this.userDAO = userDAO; CGZ^hoh/
} "!KpXBc,>
56{I`QjX
/* (non-Javadoc) 3m=2x5{L
* @see com.adt.service.UserManager#listUser LT_iS^&1
*_"u)<J
(org.flyware.util.page.Page) 3sbK7,4
*/ {G*OR,HN
public Result listUser(Page page)throws h1f8ktF
j?-R]^-5
HibernateException, ObjectNotFoundException { 7&+Ys
int totalRecords = userDAO.getUserCount(); @G*.1;jO
if(totalRecords == 0) MhxDV d
throw new ObjectNotFoundException cAEok P
au$"B/
("userNotExist"); AVFjBybu9
page = PageUtil.createPage(page, totalRecords); J@]k%h
List users = userDAO.getUserByPage(page); w4%AJmt
returnnew Result(page, users); {Uq:Xw
} H;S%Y`V
CW`!}yu%
} f Iy]/
>emcJVYV`[
*||d\peQ
_u5dC
/S~m)$vu
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 A,#2 ^dR
SaO3zz@L
询,接下来编写UserDAO的代码: .=<$S#x^Hb
3. UserDAO 和 UserDAOImpl: E FY@Y[
java代码: o8ppMM8_R[
XUSvhr$|
!#}7{
/*Created on 2005-7-15*/ FS@A8Bb
package com.adt.dao; Phs-(3
Cq\I''~8
import java.util.List; :2y"3azxk
"HlgRp]u
import org.flyware.util.page.Page; zwr\:Hu4
"b,%8
import net.sf.hibernate.HibernateException; +iA=y=;blH
NXU`wnVJ
/** a$JLc a
* @author Joa \ZH&LPAY
*/ qZ X/@Yxz
publicinterface UserDAO extends BaseDAO { DC:)Ysuj
E\ th%q,mG
publicList getUserByName(String name)throws s 3r=mp{
^Z}Ob= .G
HibernateException; fn}UBzED\
DtF}QvA
publicint getUserCount()throws HibernateException; D7?C
W?z#pV+jt
publicList getUserByPage(Page page)throws H%}IuHhN)
Y*LaBxt Q
HibernateException; 0LL c 1t>}
Zyye%Ly
} 9[Qd)%MO
~?U*6P)o
0X9Y~TM%
SEd5)0X^
g^~Kze
java代码: gEJi[E@
_[K#O,D,
z`U Ukl}T
/*Created on 2005-7-15*/ c`G&KCw)d
package com.adt.dao.impl; n&Yk<
]Pc^#=(R0
import java.util.List; io%')0p5q
IL!=mZ>2O
import org.flyware.util.page.Page; h(' )"
t"AzI8O
import net.sf.hibernate.HibernateException; }!s!;BOx
import net.sf.hibernate.Query; DQXS$uBT
:c]`D>
import com.adt.dao.UserDAO; n(vDytrj;
1HR~G9
/** ,k0r
* @author Joa 80B>L
*/ :`Az/U[
public class UserDAOImpl extends BaseDAOHibernateImpl .EP6oKA
`-UJ /{
implements UserDAO { 'Kbl3fUF
QIU,!w-3X
/* (non-Javadoc) Is.WZYa
* @see com.adt.dao.UserDAO#getUserByName 0l\y.
LE=k
(java.lang.String) [QczlwmO
*/ *"{&FEV
publicList getUserByName(String name)throws x?yD=Mq_
XbXA+ey6
HibernateException { 9#/(N#>
String querySentence = "FROM user in class N{C;~'M2ce
H+C6[W=
com.adt.po.User WHERE user.name=:name"; L;6.r3bL
Query query = getSession().createQuery olYsT**'
d"Q |I
(querySentence); xN"Z1n7t
query.setParameter("name", name); r':TMhzHq?
return query.list(); :@3Wg3N
} b1`r!B,
b.yh8|&
/* (non-Javadoc) 0GXO&rCG
* @see com.adt.dao.UserDAO#getUserCount() q6q1\YB
*/ "ZMkL)'7-
publicint getUserCount()throws HibernateException { ]MTbW=*}ED
int count = 0; q/&y*)&'O
String querySentence = "SELECT count(*) FROM 8im@4A+n`
/VTM 9)u
user in class com.adt.po.User"; USPTpjt8R
Query query = getSession().createQuery ANMg
~H /2R
(querySentence); +M\8>/0oA
count = ((Integer)query.iterate().next |M~ON=
%y`7);.q
()).intValue(); yy2I2Bv
return count; LMl~yqM
} =y]$0nh
&%C4Ugo
/* (non-Javadoc) (9RslvKL
* @see com.adt.dao.UserDAO#getUserByPage ?Dsm~bkX[
n(;:*<Rh
(org.flyware.util.page.Page) mY&ud>,U:
*/ -uR72f
publicList getUserByPage(Page page)throws N2,D:m\
xFFr
HibernateException { mZvG|P$}
String querySentence = "FROM user in class b"j|Bb
{rH9grb
com.adt.po.User"; GG6%bF
Query query = getSession().createQuery edC4BHE
kODK@w V-
(querySentence); n \G Ry'
query.setFirstResult(page.getBeginIndex()) $1Nd_pD=
.setMaxResults(page.getEveryPage()); &jQ?v@|1c
return query.list(); h
y-cG%f
} &xSa7FY
pBJAaCGm
} tiaR4PB
/CX VLl8~
{padD p
`$RA< 3
rAqxTdF
至此,一个完整的分页程序完成。前台的只需要调用 u\e\'\
zA+@FR?
userManager.listUser(page)即可得到一个Page对象和结果集对象 !]?$f=
i u]&;
的综合体,而传入的参数page对象则可以由前台传入,如果用 tpf7_YP_!-
6vy7l(%
webwork,甚至可以直接在配置文件中指定。 z01>'
(!K_Fy@
下面给出一个webwork调用示例: Oe]&(
java代码: I4_d[O9
i76 Yo5
$p* p
/*Created on 2005-6-17*/ =[tSd)D,y
package com.adt.action.user; 2 h|e
H=MCjh&$q
import java.util.List; =_TaA(79
%1U`@0
import org.apache.commons.logging.Log; 9}tG\0tL*
import org.apache.commons.logging.LogFactory; h8 @
import org.flyware.util.page.Page; @9G- m(?*
df*w>xS
import com.adt.bo.Result; RuRt0Sd3
import com.adt.service.UserService; f"5g>[1
import com.opensymphony.xwork.Action; (jWss V1
:osz
/** !dcwq;Ea
* @author Joa {U!uVQC'
*/ u:gtOjk2
publicclass ListUser implementsAction{ e]>ori
8
h5zVGr
privatestaticfinal Log logger = LogFactory.getLog t!;/Z6\Pb
RMYP"
(ListUser.class); -e@!
n-;y*kD
private UserService userService; =bt]JRU
>`T5]_a
private Page page; ]> !<G8=N
h1"zV6U
privateList users; J{"kw1Lu
b!>\2DlyJ
/* .w?
.ib(
* (non-Javadoc) s4= "kT]
* 0Fr1Ku!
* @see com.opensymphony.xwork.Action#execute() _!V%fw
*/ ^U7OMl4Usq
publicString execute()throwsException{ VV_l$E$
Result result = userService.listUser(page); B0UJq./`
page = result.getPage(); ZXb0Y2AVx
users = result.getContent(); wdE?SD s
return SUCCESS; %'Xk)-+y
} &~DTZgY
Z'v-F^
/** T6#"8qz<
* @return Returns the page. 'W. Vr4
*/ v6a]1B
public Page getPage(){ Jc*XXu)
return page; kMxazx1
} tJI,r_
w5C*L)l
/** BNGe
exs@
* @return Returns the users. pb;")Q'
*/ ZFh+x@
publicList getUsers(){ %i{;r35M;9
return users; *e"a0
} cd@.zg'sYn
8%{q%+
/** !UBO_X%dz
* @param page V1=*z
* The page to set. =H]F`[B=
*/ "kW!{n
publicvoid setPage(Page page){ TJ@Cj y%
this.page = page; -C7 FuD[Xw
} 0(>rG{u
ph:3|d
/** Mio>{%/
* @param users g9h(sLSF
* The users to set. 25{ uz
*/ **_&i!dtL
publicvoid setUsers(List users){ ")#<y@Rv
this.users = users; tOdT[&
} /ONV5IkPy
:Waox"#=g
/** "&YYO#YO
* @param userService l3i,K^YL
* The userService to set. ]n1dp2aH
*/ L-i>R:N4
publicvoid setUserService(UserService userService){ ]5CNk+`'
this.userService = userService; @ CsV]97`
} ,lN5,zI=S
} EYS>0Y
]L_w$ev'
pR os{Uq"
`|e!Kq?#Q
IfdI|ya
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, d 4{FDqto
B uQ|~V
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 h#YD~!aJ
^y.UbI
么只需要: 8}p8r|d!ls
java代码: _cI_#
FY0%XW
$r.U
<?xml version="1.0"?> [2Mbk~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1hQN8!: <
oW}!vf3z
1.0//EN" "http://www.opensymphony.com/xwork/xwork- T`YwJ6N
,32xcj}j)r
1.0.dtd"> f|3q^wjs
~ 9o6 W",
<xwork> U5ZX78>a
qc-,+sn(
<package name="user" extends="webwork- 5fjd{Y[k
!|{IVm/J
interceptors"> mNmUUj9z
{aq9i
<!-- The default interceptor stack name >=,uau7
F#r#}.B='U
--> X~U >LLr
<default-interceptor-ref `x8Bn"
8QgA@y"
name="myDefaultWebStack"/> xh9qg0d
%|Qw9sbd
<action name="listUser" Y>6.t"?Q^
$n=lsDnhQ
class="com.adt.action.user.ListUser"> {")\0|2\x
<param GlYly5F
'?Bg;Z'L %
name="page.everyPage">10</param> )najO*n
<result /MTf0^9
Fe=8O ^\
name="success">/user/user_list.jsp</result> qt?*MyfV
</action> ?Hz2-Cn
&_-](w`
</package> L K7Xw3
, |E$'
</xwork> HxwlYx,4
$xW**&
rGwIcx(%
>l1r,/\\
S'i;xL>
kT oOIx
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 b Y8GA
M?&zY
"c
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Lubrn"128
o+?@5zw-&
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 htJuGfDx1
4jwu'7Q
=7/-i
=
1|"-
[Eq<":)
我写的一个用于分页的类,用了泛型了,hoho d"<F!?8
[s6C
ZcL
java代码: 7!4V>O8@
>.%4~\U
Epjff@7A
package com.intokr.util; ^$?qT60%d|
APBK9ky
import java.util.List; :h5J r8
pA4 ,@O
/** Q+[ .Y&
* 用于分页的类<br> &y.dmW
* 可以用于传递查询的结果也可以用于传送查询的参数<br> a-0cN 9
* C8b''9t.
* @version 0.01 ?[1SiJT
* @author cheng +oy*Kxs7
*/ ;Rnhe_A.
public class Paginator<E> { QApyP CH
privateint count = 0; // 总记录数 LsTffIP
privateint p = 1; // 页编号 EQ
>t[ &
privateint num = 20; // 每页的记录数 '1+.t$"/tU
privateList<E> results = null; // 结果 "Ai6<