Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 &77J,\C$:
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 {ObY1Y`ea
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 Dz~^AuD6
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 lH_pG ~
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分页支持类: 1VFCK&
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java代码: 9'H:pb2
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package com.javaeye.common.util; 0N!rIz
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import java.util.List; l^bak]9 1
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publicclass PaginationSupport { E.m2- P;4
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publicfinalstaticint PAGESIZE = 30; >V)#y$Z
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privateint pageSize = PAGESIZE; "})OLa
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privateList items; X{cB%to
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privateint totalCount; Xmmj.ZUr
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privateint[] indexes = newint[0]; [g"nu0sOK
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privateint startIndex = 0; )
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public PaginationSupport(List items, int )!AH0p
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totalCount){ *N
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setPageSize(PAGESIZE); =jm\8sl~~
setTotalCount(totalCount); Ew.6y=Ba
setItems(items); w]xr
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setStartIndex(0); #lMIs4i.
} 8v/,<eARJ
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public PaginationSupport(List items, int =[aiW|Y
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totalCount, int startIndex){ )Dhx6xM[a
setPageSize(PAGESIZE); voRb>xF
setTotalCount(totalCount); W^HE1Dt]
setItems(items); (g[WZB3x
setStartIndex(startIndex); %8DI)n#H
} jpYZ)
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public PaginationSupport(List items, int N?rE:0SJ
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totalCount, int pageSize, int startIndex){ mDA+
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setPageSize(pageSize); 45-x$o
setTotalCount(totalCount); W+GBSl
setItems(items); (0y!{ (a
setStartIndex(startIndex); D5Rp<PBq,
} >u0XV "g$
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publicList getItems(){ R9- mq;u+
return items; p {.6
} fbdpDVmpU
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publicvoid setItems(List items){ .P5'\
this.items = items; @>ys,dy
} k&[6Ld0~56
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publicint getPageSize(){ 1)97AkN(O
return pageSize; a|]deJU^
} .*"KCQGOgM
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publicvoid setPageSize(int pageSize){ #:Q\
this.pageSize = pageSize; A[fTpS ~~%
} hDg"?{
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publicint getTotalCount(){ 7N OF^/nU
return totalCount; /i_FA]Go
} C
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publicvoid setTotalCount(int totalCount){ >ZgV8X:
if(totalCount > 0){ `l70i2xcj
this.totalCount = totalCount; b
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int count = totalCount / V4Qy^nn1
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pageSize;
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if(totalCount % pageSize > 0) u^'X>n)oL#
count++; +o,f:Ih
indexes = newint[count]; %)d7iT~M
for(int i = 0; i < count; i++){ ' qT\I8%
indexes = pageSize * 9zx9t
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} 805oV(-
}else{ P%R9\iajH
this.totalCount = 0;
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} N?,
} e `JWY9%
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publicint[] getIndexes(){ eMn'z]M&]
return indexes; 5}5oj37x
} 64"DT3:
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publicvoid setIndexes(int[] indexes){ C(>g4.-p8
this.indexes = indexes; h'vBWtMa
} =l]
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publicint getStartIndex(){ ZcHIk{|
return startIndex; t1yfSStp
} >@a7Zzl0H
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publicvoid setStartIndex(int startIndex){ 9@Cu5U]
if(totalCount <= 0) k%sxA
this.startIndex = 0; P,G
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elseif(startIndex >= totalCount) 5w~J"P6jg
this.startIndex = indexes c;a<nTLn
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[indexes.length - 1]; oxnI/Z
elseif(startIndex < 0) +l]>(k.2
this.startIndex = 0; M,oZ_tY%
else{ k7sD"xR3
this.startIndex = indexes dxS5-aWy9w
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[startIndex / pageSize]; 33~8@]b
} y
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} at\u7>;.^k
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publicint getNextIndex(){ :7Uv)@iUk
int nextIndex = getStartIndex() + '<e$ c
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pageSize; vwa*'C
if(nextIndex >= totalCount) G%!i="/9
return getStartIndex(); nLANWQk9
else /74h+.amg
return nextIndex; c|k(_#\B
} VKlC`k8L
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publicint getPreviousIndex(){ `6# s+JA[
int previousIndex = getStartIndex() - VH+3o?nrT
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pageSize; BT$Oh4y4
if(previousIndex < 0) 3U!=R-
return0; |S<!'rY
else %(K} 1[
return previousIndex; DH i@ujr
} 79o=HiOF99
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} 2BT+[
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抽象业务类 udc9KuR@
java代码: 'w<^4/L Q
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/** 0~[M[T\
* Created on 2005-7-12 'V <ZmJ2
*/ Be^"sC
package com.javaeye.common.business; ~Dw%
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import java.io.Serializable; */@I$*
import java.util.List; @~5Fcfmm
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import org.hibernate.Criteria; MJH>rsTQ
import org.hibernate.HibernateException; ^Q+z^zlC
import org.hibernate.Session; 0G Q8}r
import org.hibernate.criterion.DetachedCriteria; 6g#E/{kQw
import org.hibernate.criterion.Projections; zF? 6"
import iO18FfM_
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org.springframework.orm.hibernate3.HibernateCallback; Lm1JiPs d
import eIf-7S]m
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org.springframework.orm.hibernate3.support.HibernateDaoS Dk2Zl
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upport; l0ZK)
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import com.javaeye.common.util.PaginationSupport; ?=-/5A4K
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public abstract class AbstractManager extends ];=|))ky"
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HibernateDaoSupport { W?ghG
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privateboolean cacheQueries = false; Pj BBXI1i
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privateString queryCacheRegion; Y 9st3
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publicvoid setCacheQueries(boolean CC$rt2\e
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cacheQueries){ ~xws5n}F
this.cacheQueries = cacheQueries; )U]q{0`
} :DuEv:;v
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publicvoid setQueryCacheRegion(String _t4(H))]vG
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queryCacheRegion){ p`52
this.queryCacheRegion = IEkbVIA(
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queryCacheRegion; CU*;>h1~u
} FBzsM7]j
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publicvoid save(finalObject entity){ n%02,pC6,
getHibernateTemplate().save(entity); y;P%=MP
} V;Ln|._/t
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publicvoid persist(finalObject entity){ xsS;<uCD
getHibernateTemplate().save(entity); Of9 gS-m
} K05T`+N,
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publicvoid update(finalObject entity){ (b"q(:5oX
getHibernateTemplate().update(entity); .>-D{
} 2Ib
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publicvoid delete(finalObject entity){ ^i3!1cS
getHibernateTemplate().delete(entity); aJ1{9 5ea
} d+0= a]
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publicObject load(finalClass entity, yKm6
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finalSerializable id){ Uw3wR!:
return getHibernateTemplate().load |X6R2I
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(entity, id); DC_k0VBn
} z|(<Co8#.
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publicObject get(finalClass entity, ]<Q&
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finalSerializable id){ cBZJ
return getHibernateTemplate().get 5HY0 *\
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(entity, id); %):pfM;b
} h2?\A%
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publicList findAll(finalClass entity){ qHd7C3
return getHibernateTemplate().find("from taO(\FOm
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" + entity.getName()); 53bVhPGv
} Wdj|RKw
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publicList findByNamedQuery(finalString (>lH=&%zj
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namedQuery){
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return getHibernateTemplate MvaX>n!o
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().findByNamedQuery(namedQuery); ETdN<}m
} :$P1ps3B
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publicList findByNamedQuery(finalString query, um( xZ6&m
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finalObject parameter){ z('t#J!b
return getHibernateTemplate |~rKD c
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().findByNamedQuery(query, parameter); D)Jac@,0
} T~g`;Q%i
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publicList findByNamedQuery(finalString query, tv:
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finalObject[] parameters){ #n|eq{fkK
return getHibernateTemplate h$%h w+"4
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().findByNamedQuery(query, parameters); 'tX}6wurf
} mSk";UCn
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publicList find(finalString query){ G%K&f1q%
return getHibernateTemplate().find 2a 7"~z~
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(query); -%V~1
} <B @z>V
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publicList find(finalString query, finalObject !>GDp >0
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parameter){ HLc3KYIk
return getHibernateTemplate().find <$K7f
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(query, parameter); lW4 6S
} i4M%{]G3Y
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public PaginationSupport findPageByCriteria \}YAQ'T
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(final DetachedCriteria detachedCriteria){ "QBl
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return findPageByCriteria p
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); wb##|XyK<c
} nAX/u[
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public PaginationSupport findPageByCriteria (''w$qq"D
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(final DetachedCriteria detachedCriteria, finalint 9j5-/
3[ xHY@c
startIndex){ K=pG,[ChA
return findPageByCriteria ^nDa-J$
"}oo`+]Cq
(detachedCriteria, PaginationSupport.PAGESIZE, UoSc<h|
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startIndex); joNV4v"=`
} >Qg-dJt[
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public PaginationSupport findPageByCriteria 1Cw$^jd
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(final DetachedCriteria detachedCriteria, finalint HLL=.: P
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pageSize, ~w.y9)",
finalint startIndex){ iDltN]zS
return(PaginationSupport) ^E~1%Md.
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getHibernateTemplate().execute(new HibernateCallback(){ e-VGJxR
publicObject doInHibernate 7=&+0@R#/d
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(Session session)throws HibernateException { K%u>'W
Criteria criteria = T#vY(d
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detachedCriteria.getExecutableCriteria(session); vV"I}L
int totalCount = QcjsQTAbk
w U1[/
((Integer) criteria.setProjection(Projections.rowCount SEE:v+3|
#Kx @:I
()).uniqueResult()).intValue(); Tz0XBH_
criteria.setProjection /fU-0a8
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(null); bik lja
List items = w?Cho</Xu
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criteria.setFirstResult(startIndex).setMaxResults J5z\e@?.0\
>X=V Ph8
(pageSize).list(); vZ^U]h V
PaginationSupport ps = 7 ;2>kgf~
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new PaginationSupport(items, totalCount, pageSize, m8+
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startIndex); ['3E'q,4&
return ps; #nmh=G?\Sm
} bkrl>Im<n
}, true); .
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} CdtCxy5
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public List findAllByCriteria(final 6 B7F
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DetachedCriteria detachedCriteria){ Vo|[Z)MO`
return(List) getHibernateTemplate ~ftR:F|9
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().execute(new HibernateCallback(){ 7loWqZ
publicObject doInHibernate V6k Dyl(
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(Session session)throws HibernateException { 5XuQQ!`
Criteria criteria = w@\4ft6d
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detachedCriteria.getExecutableCriteria(session); Z>dvth
return criteria.list(); |;I"Oc.w^R
} 7f<@+&
}, true); 1Ve~P"w
} *qxv"PptX
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public int getCountByCriteria(final 0_=^#r4Mu
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DetachedCriteria detachedCriteria){ ZS`9r16@b
Integer count = (Integer) ;q#Pl!*5
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getHibernateTemplate().execute(new HibernateCallback(){ j(M.7Z7^
publicObject doInHibernate Bw9O)++
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(Session session)throws HibernateException { -U\s.FI.AR
Criteria criteria = $+,kibk*R
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detachedCriteria.getExecutableCriteria(session); 5,\|XQA5!
return E
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criteria.setProjection(Projections.rowCount m6Qm }""
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()).uniqueResult(); M<Y{Cs
} LKZv#b[h
}, true); p}Bh
return count.intValue(); g!z &lQnZ
} ,L-V?B(UQ
} pIKfTkSqH
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用户在web层构造查询条件detachedCriteria,和可选的 N Ff`V
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 &z>iqm"Ww
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PaginationSupport的实例ps。 nB}eJD|
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ps.getItems()得到已分页好的结果集 tq L2' (=
ps.getIndexes()得到分页索引的数组 6H;\Jt
ps.getTotalCount()得到总结果数 mApl;D X
ps.getStartIndex()当前分页索引 ']Z%6_WF
ps.getNextIndex()下一页索引 :!FGvR6
ps.getPreviousIndex()上一页索引 @ *5+ZAF
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 &4*f28 s
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 N37CAbw0
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一下代码重构了。 &3itBQF
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我把原本我的做法也提供出来供大家讨论吧: hI*6f3Vn(n
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首先,为了实现分页查询,我封装了一个Page类: +6L.a3&(b
java代码: bzZ7L-yD
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/*Created on 2005-4-14*/ ![eipOX
package org.flyware.util.page; 7'ws: #pC
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/** g3Ul'QJ
* @author Joa (v$
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* \)2'+R
*/ fe}RmnAC
publicclass Page { EH'eyC-B<
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/** imply if the page has previous page */ L\"eE'A
privateboolean hasPrePage; w*u.z(:a`
g<:TsP'|
/** imply if the page has next page */ c57`mOe/b
privateboolean hasNextPage; },O7NSG<o
OK
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/** the number of every page */ @scSW5+
privateint everyPage; ler$HA%F]
@k/|%%uP
/** the total page number */ \JP9lJ3<
privateint totalPage; 8rNf4]5@X(
}$a*XY1
/** the number of current page */ 'yh)6mid
privateint currentPage; oMNBK/X_
Wq<HsJd/
/** the begin index of the records by the current tn |H~iF{
VY@`)
query */ WJ\,Y} J
privateint beginIndex; ^xr &E
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/** The default constructor */ }x_:v!G
public Page(){ H8E#r*"-m
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} :aD_>,n
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/** construct the page by everyPage }G"bD8+
* @param everyPage A'*#UYn(
* */ \3x+Z!
public Page(int everyPage){ cxIAI=JK
this.everyPage = everyPage; z\K-KD{Ad
} WqHp23
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/** The whole constructor */ }#nd&ND
public Page(boolean hasPrePage, boolean hasNextPage, ayN[y
LVy (O9g
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int everyPage, int totalPage, 8w~X4A,
int currentPage, int beginIndex){ (62Sc]
this.hasPrePage = hasPrePage; 02^Nf7DMR
this.hasNextPage = hasNextPage; SOS|3q_`
this.everyPage = everyPage; /5?tXH"
this.totalPage = totalPage; V} h)e3X
this.currentPage = currentPage; *(sv5c!0M8
this.beginIndex = beginIndex; (Y"./BDY
} p<B*)1Tj0
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/** 1W7ClT_cQ
* @return "_\77cqpTh
* Returns the beginIndex. 9CZEP0i7
*/ /^`do3a}
publicint getBeginIndex(){ LXRIo2ynuw
return beginIndex; o3le[6C/8=
} A=np?wc
6L-3cxqf\
/** U \F ?{/
* @param beginIndex ayLINpL
* The beginIndex to set. [MeFj!(
*/ JE;!~=
publicvoid setBeginIndex(int beginIndex){ cq$_$jRx
this.beginIndex = beginIndex; A!a.,{fZ
} qh6Q#s>tH
9Wdx"g52_D
/** r$,Xv+}
* @return $8Gj9mw4e'
* Returns the currentPage. mD,fxm{G
*/ 2>xEE
publicint getCurrentPage(){ H$6;{IUz~
return currentPage; M4t:)!dji?
} pwNF\ ={
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/** ,fhK
* @param currentPage RZ?abE8
* The currentPage to set.
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*/ X//=OpS`
publicvoid setCurrentPage(int currentPage){ yY"n: &T(
this.currentPage = currentPage; -e_pw,5c '
} }?9 A:&
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/** Hr*xA x
* @return 2xv[cpVi
* Returns the everyPage. Q|7m9~
*/ )p{,5"0u
publicint getEveryPage(){ p }3$7CR/
return everyPage; f/sLQdK,
} -E.fo._L5
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/** BfD C[(n`
* @param everyPage L!Gpk)}[i
* The everyPage to set. nlc$"(eA[H
*/ ^a7a_M
publicvoid setEveryPage(int everyPage){ {-hu""x>
this.everyPage = everyPage; 5GURfG3{
} F1%^,;
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/** D*g
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* @return w$jSlgUHy)
* Returns the hasNextPage. :bqUA(k
*/ HHT8_c'CC#
publicboolean getHasNextPage(){ U(hIT9
return hasNextPage; ?',GR aD
} ?:+p#&I
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/** P6`LUyz3
* @param hasNextPage ~eXI}KhBw6
* The hasNextPage to set. ##s:Ww
*/ ]ts^h~BZ$
publicvoid setHasNextPage(boolean hasNextPage){ sl)]yCD|5
this.hasNextPage = hasNextPage; $|I hO
} <Kk?BRxi
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/** ~bgM*4GW
* @return 6|1*gl1_LD
* Returns the hasPrePage. 4p>,
*/ Tzfk_h3hE
publicboolean getHasPrePage(){ -(zw80@&
return hasPrePage; Tz7|OV_W$
} {`9J8qRY
O:#/To'
/** -gv[u,R
* @param hasPrePage UryHte
* The hasPrePage to set. "J2v8c
*/ `~h8D9G
publicvoid setHasPrePage(boolean hasPrePage){ 3o#K8EL
this.hasPrePage = hasPrePage; eyos6Qi
} ;7(vqm<V2~
ceae~
/** n]3Z~HoZ
* @return Returns the totalPage. :#=BwdC
* m[hHaX
*/ Q}1qt4xy*
publicint getTotalPage(){ -#r=
return totalPage; 'K|F{K
} 4Dasj8GsV
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/** <,J O
* @param totalPage u`pw'3hY
* The totalPage to set. [+qB^6I+P%
*/ l=47#zbpZ]
publicvoid setTotalPage(int totalPage){ sRflabl *x
this.totalPage = totalPage; _Bhd@S!
} ;6`7
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} pAyUQe;X#
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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 0"iQHi
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个PageUtil,负责对Page对象进行构造: eH%i8a
java代码: y_T%xWK5
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/*Created on 2005-4-14*/ wIF)(t-):
package org.flyware.util.page; \(U|&
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import org.apache.commons.logging.Log; /1.gv~`+
import org.apache.commons.logging.LogFactory; Kj:'Ei7
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/** Iz&<rL;s
* @author Joa '<AE%i,
* *]ME]2qP
*/ !ozHS_
publicclass PageUtil { 9 $zx<O
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privatestaticfinal Log logger = LogFactory.getLog $LtCI
Cf@N>N#t)
(PageUtil.class); 9/O\769"'
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/** I<S*"[nV
* Use the origin page to create a new page ngzQVaB9
* @param page |Rb8/WX
* @param totalRecords Srrzj-9^)K
* @return S0;s
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*/ DK#Tr: 7
publicstatic Page createPage(Page page, int 2 y&k
yg"FF:^T
totalRecords){ }L>0}H
return createPage(page.getEveryPage(), -c%'f&P
vh^?M#\
page.getCurrentPage(), totalRecords); kM3#[#6$!
} >vNE3S_
ty8E;['
/** 2D"aAI<P
* the basic page utils not including exception :v^Od W
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handler H~W=#Cx
* @param everyPage H2CpZK'
* @param currentPage Oo9'
* @param totalRecords l^rQo_alk
* @return page _hEr,IX=J
*/ E+Dcw
publicstatic Page createPage(int everyPage, int aO*v"^oF
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currentPage, int totalRecords){ :71St'
everyPage = getEveryPage(everyPage); &cy<"y
currentPage = getCurrentPage(currentPage); ]vH:@%3U
int beginIndex = getBeginIndex(everyPage, 4 Z&KR<2Z
fj[Kbo 7!h
currentPage); Z5[g[Q
int totalPage = getTotalPage(everyPage, !'a
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l_P90zm39!
totalRecords); xn1,
o
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boolean hasNextPage = hasNextPage(currentPage, F:LrQu
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totalPage); +_ny{i`'
boolean hasPrePage = hasPrePage(currentPage); A&X
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returnnew Page(hasPrePage, hasNextPage, )oZ2,]us!
everyPage, totalPage, n39EKH rm%
currentPage, EEiWIf&S,
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beginIndex); 6u{%jSA>D\
} </W"e!?X
40 zO4
privatestaticint getEveryPage(int everyPage){ Uv!VzkPfo
return everyPage == 0 ? 10 : everyPage; mBQpf/PG
} Au*1-
8qoA5fW>
privatestaticint getCurrentPage(int currentPage){ 8(
bK\-b
return currentPage == 0 ? 1 : currentPage; @QF;m
} ~iq=J5IN#
g-cg3Vso
privatestaticint getBeginIndex(int everyPage, int ^,`
L!3
`tl -] ^Y2
currentPage){ =Ea,8bpn
return(currentPage - 1) * everyPage; CW+gZ!
} ulfs Z:
DH:9iX '
privatestaticint getTotalPage(int everyPage, int cvYKZB
OXbC\^qo@
totalRecords){ j_S3<wEJ
int totalPage = 0; LdnTdh?
(iht
LFp
if(totalRecords % everyPage == 0) VOT9cP^6
totalPage = totalRecords / everyPage; ,Qj\_vr@
else 7?\r9bD
totalPage = totalRecords / everyPage + 1 ; )M@^Z(W/a
}sp?@C,Z
return totalPage; .I%B$eH
} {*nE8+..A
W >|'4y)
privatestaticboolean hasPrePage(int currentPage){ }6*JX\'q
return currentPage == 1 ? false : true; u\km_e
} EF;B)y=
_S CY e
privatestaticboolean hasNextPage(int currentPage, IEWl
I
(@S9>z4s
int totalPage){ Pd~z%VoO
return currentPage == totalPage || totalPage == 'Y]<1M>.g
?i}wm`
0 ? false : true; ){w!<Lb
} 1U
='"
1 K]
2L=(-CH9]
} c$_}
_,w*Rv5=
4}]In/yA
FV%|*JW[;N
S4OOm[8
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。 ^b*ub(5Ot
N5b&tJbM0
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 o@YEd d
NU[Wj uLG
做法如下: 8an_s%,AW
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 {6F]w_\
5,R<9FjW
的信息,和一个结果集List: w7~&Xxa/
java代码: LtNspFoLb
" pL5j
qnO/4\qq
/*Created on 2005-6-13*/ ryTtGx%a
package com.adt.bo; #?~G\Ux0/
T? ,Q=.
import java.util.List; YW"nPZNPy~
o^u}(wZ{
import org.flyware.util.page.Page; Wr,pm#gl6
G ahY+$L,
/** > Qh#pn*
* @author Joa l
Ng)k1
*/ j0S[JpoF
publicclass Result { y <P1VES
mQ\oR|
private Page page; 8vUq8[[
DhG{hQ[[
private List content; DMT2~mh
^k!u
/** o|V=3y
Ok
* The default constructor ST\d-x
*/ oSP^
.BJ$
public Result(){ }$:ha>
super(); +b{tk=Q:
} 4*Z>-<W=
&y ~GTEP
/** a1ai?},
* The constructor using fields 'zuA3$SR
* !XY}\zKq
* @param page x%RE3J-
* @param content 2O`s'&.h
*/ OPDRV\
public Result(Page page, List content){ z!^3%kJJ>
this.page = page; U?ZxQj66}
this.content = content; N'8}5Kx5
} Y IVN;:B.
}k6gO0z
/** *w1R>
* @return Returns the content. qox@_
*/ `R:HMO[ow
publicList getContent(){ T2k# "zD
return content; ]ov"&,J
} 3yM!BTlX
yzJTNLff
/** 0,m@BsK
* @return Returns the page. {c=H#- A
*/ d~O)mJ
J
public Page getPage(){ g=kuM
return page; ;3N>m|?D=
} Fx@@.O6
{IQCA-AI
/** Vxim$'x!
* @param content \@*D;-b
* The content to set. <{A |Xs
*/ qF4pTQf
public void setContent(List content){ P!lTK
this.content = content; *7!*kqg!u
} G+jcR; s
_6MNEoy?
/** _<;westq
* @param page {@3p^b*E)1
* The page to set. RQd5Q.
*/ ~@EBW3>~5
publicvoid setPage(Page page){ Rs1JCP=d8
this.page = page; "\x\P)j0>
} ?1/wl;=fm
} PD@@4@^
SR&'38UCe
*qL"&h5W
w_^g-P[o-
Ck^jgB.7
2. 编写业务逻辑接口,并实现它(UserManager, e{`DvfY21
v/}hy$7
UserManagerImpl) C-L[" O0[
java代码: M9dUo7
|%7OI#t^
gX*i"Y#
/*Created on 2005-7-15*/ YDo,9
package com.adt.service; EyPF'|Qtn
Z<6Fq*I
import net.sf.hibernate.HibernateException; e(sV4Z~
;PG,0R`Z;
import org.flyware.util.page.Page; ~0XV[$`L
j?9fb
import com.adt.bo.Result; bY7~b/
7%Ii:5Bp
/** D*o[a#2_
* @author Joa 8i?h{G IMV
*/ h**mAa0fo
publicinterface UserManager { FQ6{NMz,h
gjhWoZV
public Result listUser(Page page)throws BX6]d:S
,daZKxT
HibernateException; tz"zQC$
{w|KWGk2
} N"#=Q=)x
5K %
9x9~u8j
9='=wWW
rJ}k!}G
java代码: i2+vUl|;Z
>6zXr.
a76`"(W
/*Created on 2005-7-15*/ V61.UEN
package com.adt.service.impl; zWEt< `1M
4GTB82V$
import java.util.List; gay6dj^
M4(`o^n
import net.sf.hibernate.HibernateException; yu]nK-Y7S
H@pF3gh
import org.flyware.util.page.Page; +~]LvZtI_
import org.flyware.util.page.PageUtil; ~J,e^$u
^N_ ?&pgy
import com.adt.bo.Result;
[EU\-
import com.adt.dao.UserDAO; X7gtR|[
import com.adt.exception.ObjectNotFoundException; J`x!c9 zg7
import com.adt.service.UserManager; {!rpE7P-
-R-|[xN
/** B\}B
H
* @author Joa 5(sWV:_2
*/ p[lciWEW
publicclass UserManagerImpl implements UserManager { ON/U0V:v
7*&$-Hv
private UserDAO userDAO; R-2V C
WGrG#Kw[
/** "G3zl{?GP
* @param userDAO The userDAO to set. =ADdfuKN
*/ ^`XTs!.
publicvoid setUserDAO(UserDAO userDAO){ k+FiW3-
this.userDAO = userDAO; H%AC *,
} 8f0Ytfhw
4?)-;Hx_X
/* (non-Javadoc) t&99ZdE
* @see com.adt.service.UserManager#listUser &;O)Dw
IrZ!.5%tV
(org.flyware.util.page.Page) P<WCW3!JZ
*/ *n h.&Mv|
public Result listUser(Page page)throws 2gnmk
TyF
ZhpbbS
HibernateException, ObjectNotFoundException { d*{NAq'9X
int totalRecords = userDAO.getUserCount(); V
K)%Us-
if(totalRecords == 0) o1(?j}:c|
throw new ObjectNotFoundException (jY -MF3
,:1_I`d>#X
("userNotExist"); E)=X8y
page = PageUtil.createPage(page, totalRecords); [nnX,;
List users = userDAO.getUserByPage(page); j[Xci<m
returnnew Result(page, users); dW8M^A&
} :>'4@{'
\h}a?T6
} 2'6:fr=R
)HN,A z"
IT\lkF2
s,|s;w*.
Z-D4~?Tv
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _;1H2o2f
C_JDQByfL
询,接下来编写UserDAO的代码: JM-rz#;1
3. UserDAO 和 UserDAOImpl: (?7=$z!h
java代码: uqg#(ADy?R
Px<*n '~}
zz1e)W/
/*Created on 2005-7-15*/ ]VU a$$
package com.adt.dao; g,N"o72)
IfdgMELk
import java.util.List; N$i|[>`j
If*t$f>y4N
import org.flyware.util.page.Page; LgX"Qk&Ca
dLs40 -R
import net.sf.hibernate.HibernateException; a;2Lgv0/
*Bgk3(n)
/** .^%!X!r
* @author Joa _Bh ^<D-
*/ CQ+WBTiC
publicinterface UserDAO extends BaseDAO { ZV;lr Vv
s28rj6q
publicList getUserByName(String name)throws '[nH]N
3:;2Av2(X.
HibernateException; j\Z/R1RcW
9.
7XRxR^
publicint getUserCount()throws HibernateException; xxN=,p
rg^
publicList getUserByPage(Page page)throws Jn>6y:s
Jt3]'Nr04@
HibernateException; c88I"5@[bD
$O/@bh1@p
} %;Dp~T`0
7Q(5Nlfcz
7Q>*]
)Bq~1M 2
smM*HDK
java代码: C)r!;u)AZH
D/$$"AT
f.4m6"1
/*Created on 2005-7-15*/ HJn
package com.adt.dao.impl; Z,~EH
,`3kDqS_4
import java.util.List; ;be2sTo
<opBOZ
d
import org.flyware.util.page.Page; FD&"k=p+X
l }i
.
import net.sf.hibernate.HibernateException; 7;UUS1
import net.sf.hibernate.Query; G:]w
UC\
MU ;
L7^
import com.adt.dao.UserDAO; JDyP..Dt
A{:PpYs
/** )9L:^i6
* @author Joa ?y\gjC6CNG
*/ `~bnshUk
public class UserDAOImpl extends BaseDAOHibernateImpl 2^}E!(<
=vv4;az
X
implements UserDAO { y3 R+060\3
L;7x2&
/* (non-Javadoc) T-:
@p>
* @see com.adt.dao.UserDAO#getUserByName YmS}*>oz
f,?P1D\
(java.lang.String) ]&')#YO
*/ Ighd,G-
publicList getUserByName(String name)throws `(r[BV|h}
gsqpQq7
HibernateException { yJ(p-3O5
String querySentence = "FROM user in class MmjeFv
(qDu|S3P
com.adt.po.User WHERE user.name=:name"; p#~Dq(Q
Query query = getSession().createQuery
`@acQs;0
Qg \OJmv
(querySentence); JY+ N+c\
query.setParameter("name", name); ccUq!1
return query.list(); q&h&GZ
} oCBZ9PGkK
}=':)?'-.
/* (non-Javadoc) ,<[Q/:}[
* @see com.adt.dao.UserDAO#getUserCount() !18M!8Xea
*/ [f'V pId8
publicint getUserCount()throws HibernateException { :<
int count = 0; ;'.[h*u~<
String querySentence = "SELECT count(*) FROM 0u]!C"VX
Xgge_`T9
user in class com.adt.po.User"; ] Fx9!S
Query query = getSession().createQuery 1]L 0r
C0xjM0
(querySentence); hcvWf\4'#q
count = ((Integer)query.iterate().next >i> %@
rpk
)i:k\
()).intValue(); r>=)Y32Q
return count; \;z*j|;B
} _] ~ gp.
NArql
/* (non-Javadoc) %"2;i@
* @see com.adt.dao.UserDAO#getUserByPage : GZx-
?N
6'*2{NT
(org.flyware.util.page.Page) v'"0Ya
*/ =tJ}itcJ'
publicList getUserByPage(Page page)throws pq 4/>WzE
$"d< F3k
HibernateException { 2L#$WuM~^
String querySentence = "FROM user in class LRqBP|bjCD
zFy0SzF
com.adt.po.User"; wzr3y}fCe
Query query = getSession().createQuery u? a*bW
JmJ8s hq
(querySentence);
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query.setFirstResult(page.getBeginIndex()) Oy:;v7
.setMaxResults(page.getEveryPage()); k^
CFu
return query.list(); _;]
3w
} de?Bn+mvi.
]]\\Y|0
} 5",@!1ju
'!)|;qe
Jww LAQ5
!TJCQ[Aa}
v !~lVv&
至此,一个完整的分页程序完成。前台的只需要调用 oUMY?[Wp
O@@=ZyYwc
userManager.listUser(page)即可得到一个Page对象和结果集对象 GXV<fc"1
WD=#. $z$
的综合体,而传入的参数page对象则可以由前台传入,如果用 g1JBssw&m
}B=`nbgIG7
webwork,甚至可以直接在配置文件中指定。 orB8q((
;(cqaB
下面给出一个webwork调用示例: #$&!)13
java代码: k_p4 f %9
xef@-%mcoy
50:gk*hy
/*Created on 2005-6-17*/ ;aJBx
package com.adt.action.user; S&y (A0M
iw!kV
import java.util.List; ~_SoP
H"_ZqEg
import org.apache.commons.logging.Log; :zXkQQD8`
import org.apache.commons.logging.LogFactory; 4ZY0!'be-R
import org.flyware.util.page.Page; ,q F;#nB-
g5gq{KlU
import com.adt.bo.Result; iXp*G52
import com.adt.service.UserService; yQA6w%
import com.opensymphony.xwork.Action; #HjiE
Ww9%6 #it
/** &,pL3Qos
* @author Joa KLpe!8tAe
*/ Xx~ za{p
publicclass ListUser implementsAction{ FOB9J.w4
D$W&6'
privatestaticfinal Log logger = LogFactory.getLog 26yjQ
x>5"7MR`
(ListUser.class); otQulL)T/
b5kw*h+/'h
private UserService userService; ai7*</ls
-e6~0%X
private Page page; K:PPZ|
]?n)!u
privateList users; !"w1Pv,
?!R
Z~~d
/* C5Fk>[fS
* (non-Javadoc) "pdq_35
* W,<P])
* @see com.opensymphony.xwork.Action#execute() Q;]g9T[)
*/ S2/6VoGE
publicString execute()throwsException{ \ /(;LHWQ
Result result = userService.listUser(page); DYS|"tSk
page = result.getPage(); A=LyN$%
users = result.getContent(); %A@Q %l6
return SUCCESS; XH_XGzBQS
} 5$kv,%ah
1'qllkT
/** %#!pAUP\&
* @return Returns the page. F9DY\EI
*/ >'>onAIL
public Page getPage(){ 8cq H0{
return page; 3l?D%E]P
} )<w`E{q
6\MH2&L<
/** X2avo|6e
* @return Returns the users. GfEg][f
*/ @<$-*,
publicList getUsers(){ ig
Mm.1>
return users; W2CCLq1(
} mez )G|
[ugBVnma
/** fmuAX w>
* @param page QLx]%E\
* The page to set. s bf\;_!
*/ *h=|KOS
publicvoid setPage(Page page){ >Qk4AMIO
this.page = page; K8,fw-S%
} eK%~`Y
}]0f -}
/** 9mdp\A
* @param users h?f)Bt}ry
* The users to set. vWbf5?
*/ ^a=,,6T
publicvoid setUsers(List users){ FX+;azE7
this.users = users; 5v51:g>c
} ![ &
go
EZ+_*_9
/** 8mM^wT
* @param userService ,j{$SuZM
* The userService to set. J|k~e,C
*/ d|UK=B^x
publicvoid setUserService(UserService userService){ Za+26#g
this.userService = userService; -"u9s[L{
} ; Drt4fOxX
} -p|@En n
577H{;pW
/ESmQc:DWB
yFp8 >
Gy*6I)l
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, hhu!'(j
aE0yO#=
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 Iu`B7UOF
a?]Ow J
么只需要: *KF-q?PBb
java代码: /IDfGAE
XWQp-H.
joa|5v'
<?xml version="1.0"?> W~ 6ii\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork MV"aO@
lNtZd?=>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ]AlRu(
}nrl2yp:%
1.0.dtd"> wgm?lfX<
mT8")J|2
<xwork> :Gyv%>.
$7q'Be@{
<package name="user" extends="webwork- \IZfp=On
K2J DG.<
interceptors"> 6PETIs
/aa'ryl_%
<!-- The default interceptor stack name c hE~UQ
B2UQO4[w
--> h#K863
<default-interceptor-ref n
GE3O#fv
ZU%7m_ zO
name="myDefaultWebStack"/> u@v0I$
`&2AN%Xz
<action name="listUser" W (N@`^
t\2Lo7[Pu
class="com.adt.action.user.ListUser"> w{$t:l)2,
<param ;IX3w:Aw
$j(2M?.>#
name="page.everyPage">10</param> y:Ycn+X.
<result bqmOfGM
#`P4s>IL1
name="success">/user/user_list.jsp</result> Pyc/6~?
</action> .VF4?~+M-
uVJ;1H!
</package> wTBp=)1)f
q7-Eu4w
</xwork> uQ4WM
zItf>j7|Z
y"=j[.
a%Ky;ys
&f1dCL%z7
E7E>w#T5
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Jt6~L5[_s
X5kIM\
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ;5tSXgGw7
D@T>z;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 AtNu:U$
F5Tah{
b?U!<s.
%H\i}}PTe
LO8V*H(
我写的一个用于分页的类,用了泛型了,hoho w]w>yD>$
Lc;4 Hg
java代码: mVGQyX
A@^e4\
/I~iUND"G
package com.intokr.util; @A(*&PU>j
56(S[
import java.util.List; XBv:$F.>$
M/
@1;a@\
/** &-#!]T-P:E
* 用于分页的类<br> aaf\% ~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> F$Q(2:w
* F)4Y;;#
* @version 0.01 &mj98
* @author cheng {<7!=@j
*/ b!VaEK
public class Paginator<E> { 9j458Yd4*
privateint count = 0; // 总记录数 tiJY$YqA
privateint p = 1; // 页编号 >jU.R;H5
privateint num = 20; // 每页的记录数 .L'>1H]B
privateList<E> results = null; // 结果
ks=jv:
6Zwrk-,A
/** (Nd5VuI
* 结果总数 DYlu`j_ux
*/ "`Q~rjc$2
publicint getCount(){ Q:$<`K4)
return count; yLFc?{~7
} p(/PG+
)F;`07
publicvoid setCount(int count){ 1au1DvH
this.count = count; ?<c)r~9]
} 7c|8>zES:E
gV]]?X&
/** _SM5x,Zd
* 本结果所在的页码,从1开始 E/9h"zowS
* >h>X/a(=~
* @return Returns the pageNo. !kZ9Ox9^
*/ 3# G;uWN-
publicint getP(){ 4R-Y9:^t
return p; 4 f/2gI1@B
} zJNiAc
V,?i]q;5
/** {Lu-!}\NP
* if(p<=0) p=1 BE/#=$wPjM
* [r%WVf.#d
* @param p n@[&SgZq
*/ <oG+=h
publicvoid setP(int p){ q6'3-@%
if(p <= 0) NqcmjHvy
p = 1; WT$m*I
this.p = p; i8A{DMc,U
} nsWenf
INZycNqm,
/** JFe %W?}.D
* 每页记录数量 wb^Yg9
*/ !\wdX7%
publicint getNum(){ Oz{.>Pjn^o
return num; (6i)m
c(
} 1SoKnfz{6
L<bZVocOb_
/** ]O2ku^yM
* if(num<1) num=1 )3g7dtq}
*/ ZGrjb22M
publicvoid setNum(int num){ ?r"][<
if(num < 1) sr%tEKba)
num = 1; "TB4w2?=
this.num = num; +-~hl
} ],vUW#6$N
6B
4Sd
/** ^mr#t #[e
* 获得总页数 F;p>bw
*/ DI O @Zo
publicint getPageNum(){ Q*|O9vu'D
return(count - 1) / num + 1; SiJ0r
@
} J9J[.6k8
/HR9(j6
/** 't".~H_V
* 获得本页的开始编号,为 (p-1)*num+1 *oLAO/)n
*/ sdP% Y<eAT
publicint getStart(){ MkJ}dncg*
return(p - 1) * num + 1; FtbqZN[
} csZIBi
Qzy[
/** {H
OvJ`tM
* @return Returns the results. yyZ}qnbx]
*/ Bs2.$~
publicList<E> getResults(){ oK1"8k|Z
return results; yGl
(QLk
} b5u_x_us|
\q#s/&b
public void setResults(List<E> results){ z-(@j;.
this.results = results; GFd~..$
} -AwR$<q'
ZzfGs
public String toString(){ `M?C(
StringBuilder buff = new StringBuilder yU"lW{H@
NQS@i'W=g
(); Pk444_"=
buff.append("{"); D)z'FOaI
buff.append("count:").append(count); q]Gym 7o
buff.append(",p:").append(p); o"D`_ER
buff.append(",nump:").append(num); Rz%
Px: M
buff.append(",results:").append }m NP[L
e;8>/G
(results); Pnq[r2#]:
buff.append("}"); ?Pz:H/$
return buff.toString(); l/[0N@r~
} %jEdgD%xV
}5dYmny
} :_v/a+\n
SpbOvY=>
N\b%+vR