Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 f.!cR3XgV
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 , =#'?>Kq
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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 EM"YjC)F
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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 /gxwp:&lY
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分页支持类: kc}e},k
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java代码: 4]Krx
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package com.javaeye.common.util; g1Aq;Ah /
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import java.util.List; <MoWS9s!yb
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publicclass PaginationSupport { B7cXbUAQs
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publicfinalstaticint PAGESIZE = 30; }_K7}] 1
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privateint pageSize = PAGESIZE; ?>2k>~xlQ
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privateList items; m!g
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privateint totalCount; Y6+nfh_
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privateint[] indexes = newint[0]; 8xLvpgcZ
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privateint startIndex = 0; <}G7#xg
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public PaginationSupport(List items, int 90;[5c
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totalCount){ a(F%M
setPageSize(PAGESIZE); A%pcPzG;
setTotalCount(totalCount); {@k5e)
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setItems(items); K"eW.$
setStartIndex(0); QD<f)JZK
} :hZYh.y\l
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public PaginationSupport(List items, int >-f`mT
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totalCount, int startIndex){ ]"^U
setPageSize(PAGESIZE); q* +}wP
setTotalCount(totalCount); Ve<l7U;
setItems(items); fVw+8 [d0
setStartIndex(startIndex); $`mxOcBmQ
} fs\l*nBig
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public PaginationSupport(List items, int Nw8lg*t"
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totalCount, int pageSize, int startIndex){ Dr&2qX!
setPageSize(pageSize); c5pF?kFaD
setTotalCount(totalCount); &0~E+
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setItems(items); 8e x{N3
setStartIndex(startIndex); Hr:WE+'
} LNtBYdB`pK
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publicList getItems(){ ,@Xl?
return items; p1q"[)WVn^
} Bi9 S1p
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publicvoid setItems(List items){
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this.items = items; 6|L<?
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} >2TDYB|;
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publicint getPageSize(){ NZ7g}+GTG
return pageSize; m\RU|Z
} s7[du_)
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publicvoid setPageSize(int pageSize){ Ru`&>E
this.pageSize = pageSize; >:WnCkbp
} |\Nu+w
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publicint getTotalCount(){ {%*,KB>b
return totalCount; ,E<(K8
} OW;]=k/(
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publicvoid setTotalCount(int totalCount){ 0"#'Z>"
if(totalCount > 0){ 4cDjf~n
this.totalCount = totalCount; qS:hv&~
int count = totalCount / -W<x|ph
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pageSize; QX-%<@
if(totalCount % pageSize > 0) ?#da4W
count++; {1Z8cV
indexes = newint[count]; Dyyf%'\M
for(int i = 0; i < count; i++){ Wxx?iW ,
indexes = pageSize * @@M
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i; kr[p4X4
} ux:czZqy
}else{ @z[,w`
this.totalCount = 0; mII7p LbQ
} ..'k+0u^
} d0vn/k2I
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publicint[] getIndexes(){ 2dg+R)%
return indexes; )RG@D\t ,
} LlKvi_z
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publicvoid setIndexes(int[] indexes){ ]?tC+UKb
this.indexes = indexes; kK\G+{z?
} N8S!&*m
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publicint getStartIndex(){ '#pY/,hVB
return startIndex; Myaj81
} o_R<7o/d|
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publicvoid setStartIndex(int startIndex){ 3c#oK
if(totalCount <= 0) (xxNQ]
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this.startIndex = 0; R9bsl.e
elseif(startIndex >= totalCount) dnRbt{`jP
this.startIndex = indexes J)tk<&X
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[indexes.length - 1]; ZFYv|2l
elseif(startIndex < 0)
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this.startIndex = 0; nE;^xMOK!
else{ t+y$i@R:
this.startIndex = indexes e1ts/@V
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[startIndex / pageSize]; !D#wSeJ
} =Y!x
} 4
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publicint getNextIndex(){ RI.6.f1dy
int nextIndex = getStartIndex() + }(tuBJ9
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pageSize; $$'a
if(nextIndex >= totalCount) nz_=]PHO&
return getStartIndex(); 3>vSKh1z
else B6qM0QW
return nextIndex; dAg<BK/
} o\<m99Ub
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publicint getPreviousIndex(){ I!LSDi3
int previousIndex = getStartIndex() - dRC
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pageSize; 4PdJ
if(previousIndex < 0) N!me:|Dn
return0; wwmHr!b:6
else X~+AaI:~K
return previousIndex; /1D]\k()
} )\K ;Ncp[
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} QEtf-xNn^
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抽象业务类 MX*T.TG8
java代码: 0'm$hU}
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/** ,^Ug[pGG-
* Created on 2005-7-12 ^ &UezDTS
*/ ppYIVI
package com.javaeye.common.business; 0 $Ygt0d
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import java.io.Serializable; `3wzOMgJ
import java.util.List; x&^>|'H
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import org.hibernate.Criteria; d;:H#F+ (
import org.hibernate.HibernateException; MawWgd*
import org.hibernate.Session; XHN*'@
77;
import org.hibernate.criterion.DetachedCriteria; $!Qv f
import org.hibernate.criterion.Projections; [B0]%!hFw
import mE>v (JY
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org.springframework.orm.hibernate3.HibernateCallback; 6I8A[
import ,q_'l?Pn
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org.springframework.orm.hibernate3.support.HibernateDaoS 1UHlA8w7Q
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upport; -9D2aY_>
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends #saK8; tp
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HibernateDaoSupport { pYxdE|2j
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privateboolean cacheQueries = false; (B/od# nU
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privateString queryCacheRegion; 6cQ)*,Q
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publicvoid setCacheQueries(boolean T> < Vw
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cacheQueries){ [\_#n5
this.cacheQueries = cacheQueries; b '9L}q2m
} 9e aqq
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publicvoid setQueryCacheRegion(String 'c[|\M!u
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queryCacheRegion){ o)B`K."
this.queryCacheRegion =
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queryCacheRegion; tMy<MO)Ei
} U07G&?/
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publicvoid save(finalObject entity){ xPcH]Gs^b
getHibernateTemplate().save(entity); eV"Za.a.
} 03)R_A
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publicvoid persist(finalObject entity){ $ap6Vxjr
getHibernateTemplate().save(entity); ",O}{z
} P&g.%8b~84
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publicvoid update(finalObject entity){ r.~^h^c]
getHibernateTemplate().update(entity); L/+KY_b:*
} s7
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publicvoid delete(finalObject entity){ q@@C|oqEX
getHibernateTemplate().delete(entity); P}2waJe
} [(81-j1v
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publicObject load(finalClass entity, H)@f_pfj(
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finalSerializable id){ $D%[}[2
return getHibernateTemplate().load ,suC`)R
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(entity, id); rn8#nQ>QZ%
} sI,S(VWor
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publicObject get(finalClass entity, cD 5^mxd%
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finalSerializable id){ WGC'k
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return getHibernateTemplate().get S-Z s
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(entity, id); "TQ3{=j{
} *z3wm-z1&
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publicList findAll(finalClass entity){ k6(9Rw8bCk
return getHibernateTemplate().find("from 4UV6'X)V
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" + entity.getName()); uK!G-1
} y5!fbmf
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publicList findByNamedQuery(finalString 2 y;J 11\
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namedQuery){ D,( "3zx
return getHibernateTemplate %Jb/HWC[
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().findByNamedQuery(namedQuery); O\z]1`i*o
} wU $j/~L
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publicList findByNamedQuery(finalString query, ?z/ )Hkw
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finalObject parameter){ <q<kqy5s-R
return getHibernateTemplate F?jFFwim
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().findByNamedQuery(query, parameter); /t$J<bU
} ch-.+p3
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publicList findByNamedQuery(finalString query, MEled:i
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finalObject[] parameters){ 3{/Y&/\"'^
return getHibernateTemplate 6
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().findByNamedQuery(query, parameters); C\RJ){dk
} '0MH-M
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publicList find(finalString query){ ,T<q"d7-#
return getHibernateTemplate().find #ts;s\!
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(query); !7fL'
} 1SY`V?cu
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publicList find(finalString query, finalObject n72+X
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parameter){ 9`8D Ga
return getHibernateTemplate().find R32A2Ml
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(query, parameter); NJqjW
} !\(j[d#
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public PaginationSupport findPageByCriteria Jp#Onl+d6
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(final DetachedCriteria detachedCriteria){ s/cclFji]
return findPageByCriteria =IC
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); J.;{`U=:
} xJemc3]2
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public PaginationSupport findPageByCriteria 1Bl;.8he.)
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(final DetachedCriteria detachedCriteria, finalint ?mME^?x
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startIndex){ ]A%S&q
return findPageByCriteria 'Io2",~
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(detachedCriteria, PaginationSupport.PAGESIZE, ]@G$L,3
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startIndex); vk>EFm8l
} =j&qat
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public PaginationSupport findPageByCriteria /jB0
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(final DetachedCriteria detachedCriteria, finalint -]$=.0 l
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pageSize, qbZY[Q+F
finalint startIndex){ :3h'Hr
return(PaginationSupport) = 3("gScUj
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getHibernateTemplate().execute(new HibernateCallback(){ K H&o`U(}
publicObject doInHibernate R&P}\cf8T
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(Session session)throws HibernateException { +`_Km5=
Criteria criteria = C#3K.0a
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detachedCriteria.getExecutableCriteria(session); :.J]s<J(F
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount +[C><uP
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()).uniqueResult()).intValue(); .R! /?eN
criteria.setProjection S)L(~N1
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(null); 1nAAs;`'
List items = 23_\UTM}1
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criteria.setFirstResult(startIndex).setMaxResults 78n`VmH~L
l<"Z?z
(pageSize).list(); ~IIlCmMl,
PaginationSupport ps = r{1xjAT
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new PaginationSupport(items, totalCount, pageSize, WN`|5"?$
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startIndex); *$/!.e
return ps; iM'rl0
} z($h7TZ$
}, true); )(`HEl>-9c
} Pko2fJt1
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public List findAllByCriteria(final ?loP18S
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate yD\[`!sWk
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().execute(new HibernateCallback(){ `j1(GQt
publicObject doInHibernate 6O9?":3;
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(Session session)throws HibernateException { S(MVL!Lm
Criteria criteria = x}(p\Efx
1 ^q~NYTK
detachedCriteria.getExecutableCriteria(session); trAIh}Dj
return criteria.list(); KH_~DZU*5
} eT<T[; m
}, true); 8H<:?D/tH
} Zwm2T3@e
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public int getCountByCriteria(final w>6~
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DetachedCriteria detachedCriteria){ 8<X,6
Integer count = (Integer) !hS~\+E
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getHibernateTemplate().execute(new HibernateCallback(){ u?-X07_
publicObject doInHibernate PY{])z3N
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(Session session)throws HibernateException { cZd{K[fuK
Criteria criteria = .e|VW)
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detachedCriteria.getExecutableCriteria(session); l:?w{'i$
return gxf{/EjH
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criteria.setProjection(Projections.rowCount hErO.ad1o
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()).uniqueResult(); `:y {
} (I7s[
}, true); AQR/nWwx
return count.intValue(); "oc&uj
} QO|roE
} lf?dTPrD
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用户在web层构造查询条件detachedCriteria,和可选的 Tu*"+*r>s
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 d>OLnG>
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PaginationSupport的实例ps。 !`$xN~_
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ps.getItems()得到已分页好的结果集 XI"8d.VR
ps.getIndexes()得到分页索引的数组 K[/sVaPZ
ps.getTotalCount()得到总结果数 [8OQ5}do/
ps.getStartIndex()当前分页索引 3|qT.QR`Z
ps.getNextIndex()下一页索引 hCvK2Xu
ps.getPreviousIndex()上一页索引 R3,O;9i
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 dd&n>A3O=
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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 h|Z%b_a
/%4wm?(eA
一下代码重构了。 P9/Bc^5'
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我把原本我的做法也提供出来供大家讨论吧: $22_>OsA
-o`Eka!ELz
首先,为了实现分页查询,我封装了一个Page类: c@&-c [k^W
java代码: rz'A#-?'oG
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/*Created on 2005-4-14*/ BZr$x8%ki
package org.flyware.util.page; Q(gc(bJV
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/** S(nZ]QEG
* @author Joa g4"0:^/
* |)'6U3
*/ =}h8Cl{H/
publicclass Page { Q3OGU} F
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/** imply if the page has previous page */ E` O@UW@
privateboolean hasPrePage; ,-[e{=Cz
dH8^\s .F
/** imply if the page has next page */ '1u!@=.\G
privateboolean hasNextPage; ZA>p~Zt
Yc]
/** the number of every page */ (}jYi*B
privateint everyPage; ,dZ&i!@?
S="teH[
/** the total page number */ JxlU=7cF
privateint totalPage; 1>wQ&{
g~#HiBgWq[
/** the number of current page */ ZM$}Xy\9
privateint currentPage; FR%u1fi
PRo;NE
/** the begin index of the records by the current Uw:gJ9
SmR"gu
query */ U!xOJ
privateint beginIndex; nS`DI92I
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/** The default constructor */ oI/jGyY;
public Page(){ LEJ8 .z6$
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} [
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/** construct the page by everyPage b7nER]R
* @param everyPage &Fxw19[G
* */ /ZcqKC
public Page(int everyPage){ :% o32
this.everyPage = everyPage; `_*NFv1_
} K@DK4{
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/** The whole constructor */ -N4km5
public Page(boolean hasPrePage, boolean hasNextPage, ag~4m5n*~
)X
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int everyPage, int totalPage, beN(7jo
int currentPage, int beginIndex){ Q8^fgI |
this.hasPrePage = hasPrePage; _#2AdhCu
this.hasNextPage = hasNextPage; Q,1TD2)h
this.everyPage = everyPage; x<-n}VK\
this.totalPage = totalPage;
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this.currentPage = currentPage; 8T2iqqG/1
this.beginIndex = beginIndex; kS@6'5U
} _r6aLm2n
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/** $cUTe
* @return /N'|Vs,X
* Returns the beginIndex. l_`DQ8L`
*/ >#jfZ5t
publicint getBeginIndex(){ ZV?~~_9
return beginIndex; ==i:*
} .S{Q }S
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/** Ig*qn# Dd
* @param beginIndex @fML.AT
* The beginIndex to set. 8D[,z 7n
*/ n%"0%A
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; R>05MhA+
} RkW)B^#
S<+/ Ep 2
/** Ul41RNy)
* @return ,2I8,MOg
* Returns the currentPage. c,\!<4
*/ \vU1*:3
publicint getCurrentPage(){ 0!^vQ
return currentPage; ~S='~ g)
} jZ;dY~fE
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/** -wqnmK+G
* @param currentPage m3La;%aA0
* The currentPage to set. T==(Pw7R7
*/ rTR4j>Ua~
publicvoid setCurrentPage(int currentPage){ Ai 9UB=[R
this.currentPage = currentPage; 6jGPmOM/
} U6 R"eQUTV
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/** QnWM<6xK"
* @return <`~zKFUQ[
* Returns the everyPage. ]B;\?Tim
*/ `9+>2*k
publicint getEveryPage(){ ;T6x$e
return everyPage; j#`d%eQ~J
} @L)=epC
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j~
/** 0^27grU>
* @param everyPage Ot]Y/;K
* The everyPage to set. 2I2#o9(Ar
*/ j\ dY
publicvoid setEveryPage(int everyPage){ ,s?7EHtC
this.everyPage = everyPage; LHt{y3l]
} ]Gm$0uS
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/** {u1Rc/Lw
* @return 6__#n`
* Returns the hasNextPage. T2nbU6H
*/ 7H1 ii
publicboolean getHasNextPage(){ 5g{L
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return hasNextPage; `3v!i
} 6 +:Tv2
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/** 1>doa1
* @param hasNextPage x}w"2[fL
* The hasNextPage to set. '}`|QJ
*/ (Oc[j{6q
publicvoid setHasNextPage(boolean hasNextPage){ R"au8f.
this.hasNextPage = hasNextPage; 2hjR'6h"Y
} 1D,$Az~.
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/** m]1=o7
* @return S<hj6A
* Returns the hasPrePage. rb/m;8v>
*/ ]m#.MZe
publicboolean getHasPrePage(){ 4)o_gm~6c4
return hasPrePage; :?Xd&u0){
} 5 W<\J
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/** \~(ww3e
* @param hasPrePage PgKA>50a
* The hasPrePage to set. reyN5n~4U
*/ VtR?/+8X
publicvoid setHasPrePage(boolean hasPrePage){ KPGX/l
this.hasPrePage = hasPrePage; `Z3Qx~fx
} CvCk#:@HM
Cmq.V@
/** YU89m7cc'
* @return Returns the totalPage. {[~
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* +fgF &.
*/ X7I"WC1ncz
publicint getTotalPage(){ <p48?+K9
return totalPage; ~zklrBn&
} y\'t{>U/
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/** @quNVx(y
* @param totalPage 58H [sM4>
* The totalPage to set. ^y?7B_%:B#
*/ wff&ci28
publicvoid setTotalPage(int totalPage){ $B6"fYiDk
this.totalPage = totalPage; k,L ,
}
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} \#(cI
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Wgl7)Xk.)
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个PageUtil,负责对Page对象进行构造: i$)`U]
java代码: q16RPqfT
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/*Created on 2005-4-14*/ w][1C\8m
package org.flyware.util.page; +Y!9)~f}7X
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import org.apache.commons.logging.Log; %}+!%A.3
import org.apache.commons.logging.LogFactory; 8K!
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/** ^h+<Q%'a'
* @author Joa 10v4k<xb
* 6V= 69}
*/ Q 'R@'W9
publicclass PageUtil { })OgsBk
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privatestaticfinal Log logger = LogFactory.getLog "5mdq-h(
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(PageUtil.class); VGoD2,(b^
#>-_z
/** .Od.lxz"mp
* Use the origin page to create a new page .*u, !1u
* @param page k+>-?S,
* @param totalRecords AZ)H/#be
* @return @[0zZX2EE
*/ =`5Xx(
publicstatic Page createPage(Page page, int rn
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totalRecords){ 6(4FC?Y7
return createPage(page.getEveryPage(), +'abAST
t
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page.getCurrentPage(), totalRecords); N"2Ire
} +tL]qOBP
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/** d`LBFH,
* the basic page utils not including exception ]KfjZ!Qh
?[Od.
handler UQ#"^`=R<
* @param everyPage ql5NSQ>{
* @param currentPage "d'D:>z]%
* @param totalRecords u8pJjn;
* @return page *<n]"-
*/ G>{Bij44
publicstatic Page createPage(int everyPage, int xU#f>@v!
7/lXy3B4
currentPage, int totalRecords){ T:aYv;#0
everyPage = getEveryPage(everyPage); ~6`HJ
currentPage = getCurrentPage(currentPage); !Q!==*1H
int beginIndex = getBeginIndex(everyPage, Hu|;cbK
ahNpHTPa
currentPage); B1>aR 7dsf
int totalPage = getTotalPage(everyPage, <rc? EV
/
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totalRecords); q]3bGO;
boolean hasNextPage = hasNextPage(currentPage, ^9zL[R
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j
totalPage); 1BK-uv:
boolean hasPrePage = hasPrePage(currentPage); ^ZX 71-
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returnnew Page(hasPrePage, hasNextPage, [mKPOg-t
everyPage, totalPage, <zE,T@c
currentPage, +dIO+(&g
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beginIndex); qbwX*E~;
} ZI8*PX%2
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privatestaticint getEveryPage(int everyPage){ `J(im
return everyPage == 0 ? 10 : everyPage; #'<s/7;~
} 9]DMHA@
D$wl.r
privatestaticint getCurrentPage(int currentPage){ r- :u*
return currentPage == 0 ? 1 : currentPage; Q{~ WWv
} }{(dG7G+
GQP2-cSZ
privatestaticint getBeginIndex(int everyPage, int :s}6 a23
w>]?gN?8Fe
currentPage){ eA$wJ$*
return(currentPage - 1) * everyPage; PDEeb.(.
} !&n'1gJ)kd
oJLpFL
privatestaticint getTotalPage(int everyPage, int { vf"`#Q9
`~hB-Z5dI
totalRecords){ /7)l 22<
int totalPage = 0; L/U^1=Wi*O
\:To>A32
if(totalRecords % everyPage == 0) v9<'nU WVR
totalPage = totalRecords / everyPage; 0E5"}8
else *88Q6=Mm
totalPage = totalRecords / everyPage + 1 ; aB N^J_
~rN:4Q]/
return totalPage; &`RD5uml
} Y$%z]i5
Br,^4w[Hq
privatestaticboolean hasPrePage(int currentPage){ e;kH,fHUI3
return currentPage == 1 ? false : true; :&{:$-h!
}
`|Wu\X
[vJLj>@
privatestaticboolean hasNextPage(int currentPage, I)B+h8l72<
K>tubLYh
int totalPage){ "\x<Zg;
return currentPage == totalPage || totalPage == #'@pL0dj
8{t^< j$n
0 ? false : true; zree}VqD;5
} / X
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O_M2Axm
vIL'&~C\y
} L>&o_bzp
Qrnc;H9)
!Rq.L
1TagQ
<yw6Om:n<
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。 xE2sb*
&RzkM4"
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
WB7pdSZ
xnfMx$fD
做法如下: u?J!3ZEtb
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 #%;QcDXRe
5 +Ei!E89
的信息,和一个结果集List: us,!U
java代码: *u i!|;
v*.[O/,EBR
JjXuy7XQ
/*Created on 2005-6-13*/ 3u)NkS=
package com.adt.bo; rY~!hZ
,#u"$Hz8p
import java.util.List; sUCI+)cM3
>;$C@
import org.flyware.util.page.Page; cILI%W1
,u:J"epM
/** ~6)A/]6
* @author Joa 3?d o|>
*/ t==CdCl
publicclass Result { TQ/EH~Sz
JZa^GW:YQh
private Page page; *[P"2b#
\I@hDMqv
private List content; +PlA#DZu
W7F1o[
/** ,v#F6xv8
* The default constructor X\-IAv
*/ _VjfH2Y
public Result(){ )2t DX=D
super(); u\jQe@j
'
} iOFp 9i=j
AqdQiZ^9
/** K-a~Kr
* The constructor using fields <Z nVWER
* L[|($vQ"
* @param page /#lqv)s'
* @param content StuQ}
*/ r@O5{V
public Result(Page page, List content){ m#i5}uHHg
this.page = page; 8NE+G.:G
this.content = content; >{v,HOxl
} wX!q dII)
L<}0}y
/** ^Uj\s /
* @return Returns the content. rT&rv^>f
*/ THVF(M4v
publicList getContent(){ ou{}\^DgQ
return content; zF)&o}
} 69 >-
/S9(rI<'
/** `/"rs@
* @return Returns the page. 17
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*/ Sj[iKCEKtv
public Page getPage(){ =T?:b8yV
return page; 3.t
j%+
} k%|Sl>{Ir
a_GnN\kX^Z
/** ]g3RVA%\l
* @param content 5 $vUdDTg
* The content to set. 6SJryf~w
*/ @(m+B\
public void setContent(List content){ @X|Mguq5
this.content = content; )$>
pu{o
} KE~l#=S
$+P6R`K
/** 4 kNiS^h
* @param page yx@%x?B
* The page to set. E.'v,GYe
*/ At0ahy+
publicvoid setPage(Page page){ -->~<o
this.page = page; g5YDRL!Wh
} #80[q3
} -lb,0
5}+&Em":
YLx4qE
lWR".
|+aUy^
2. 编写业务逻辑接口,并实现它(UserManager, RCL}bE
-](NMRqfN
UserManagerImpl) 9i=HZ\s3
java代码: Sb/`a~q^
xa=Lu?t%<
a7?)x])e
/*Created on 2005-7-15*/ x @a3STKT
package com.adt.service; ]SO-NR
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import net.sf.hibernate.HibernateException; ?_@_NV MY
nB &[R
import org.flyware.util.page.Page; z>6hK:27
4GN
import com.adt.bo.Result; #hQ#_7
ld7B!_b<
/** pkKcTY1Fx
* @author Joa gfW_S&&q
*/ C)a;zU;9
publicinterface UserManager { cm'`u&S
1Mtm?3Pt
public Result listUser(Page page)throws GBvgVX<
ROWI.|
HibernateException; UA8*8%v
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} sU=7)*$
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%3:[0o={d
J-k/#A4o
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java代码: it#,5#Y:
auai@)v6
na4^>:r~
/*Created on 2005-7-15*/ u^ 3,~:E
package com.adt.service.impl; eVetG,["
6z'3e\x
import java.util.List; SZ&I4-
7:S4 Ur
import net.sf.hibernate.HibernateException; hHsN(v
Po1/_#mu
import org.flyware.util.page.Page; 0XWhSrHM
import org.flyware.util.page.PageUtil; mH,L,3R;R
JS^QfT,zE
import com.adt.bo.Result; l} =@9A@
import com.adt.dao.UserDAO; v\3
\n3[u
import com.adt.exception.ObjectNotFoundException; ,8`CsY^1
import com.adt.service.UserManager; &*nq.l76X`
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/** e*!0|#-
* @author Joa 0^m`jD
*/ H5)8TR3La
publicclass UserManagerImpl implements UserManager { L>>RboR}
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private UserDAO userDAO; z#|tcHVFT
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/** y(fJ{k
* @param userDAO The userDAO to set. G(fS__z
*/ b3M`vJ+{
publicvoid setUserDAO(UserDAO userDAO){ ?nCo?A
this.userDAO = userDAO; w2(pgWed
} JGRL&MG4
unB`n'L
/* (non-Javadoc) 579<[[6~d2
* @see com.adt.service.UserManager#listUser '~\\:37+
&*YFK/ ]
(org.flyware.util.page.Page) )7jJ3G*
*/ xCYK"v6\
public Result listUser(Page page)throws 4c'F.0^
i!i=6m.q7
HibernateException, ObjectNotFoundException { \5pBK
int totalRecords = userDAO.getUserCount(); +.2OZ3(
if(totalRecords == 0) Q^{XM
throw new ObjectNotFoundException 7@NV|Idtd
/Pyj|!C3`q
("userNotExist"); .dO8I/lhV
page = PageUtil.createPage(page, totalRecords); NW4tQ;ad
List users = userDAO.getUserByPage(page); t[4V1:
returnnew Result(page, users); $l=&
} C)?tf[!_6
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} 'o]kOp@q
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 }`uFLBG3
fWz=bJ"V
询,接下来编写UserDAO的代码: eq6>C7.$
3. UserDAO 和 UserDAOImpl: VxAG=E
java代码: m|]:oT`M
Ju@8_ ?8=
A:4?Jd>
/*Created on 2005-7-15*/ xS+!/pBf"Y
package com.adt.dao; %5ovW<E:
WS6;ad;|
import java.util.List; BS|$-i5L
HDYWDp
import org.flyware.util.page.Page; $z[@DB[
^5n#hSqZ=M
import net.sf.hibernate.HibernateException; %:!ILN
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/** ey@{Ng#
* @author Joa E;rS"'D:
*/ `V2doV)
publicinterface UserDAO extends BaseDAO { HJ+Q7)
v83@J~
publicList getUserByName(String name)throws ' +f(9/
X6Q\NJ"B
HibernateException; H{4_,2h=m
:SD#>eD0
publicint getUserCount()throws HibernateException; "DC L
Z
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publicList getUserByPage(Page page)throws JI[{n~bhGD
z)ndj
1,#)
HibernateException; Sfa;;7W@R
jR2^n`D
} odTa2$O
HV=P!v6
1$)}EL
L]*5cH
)8`i%2i=
java代码: 8bdx$,$k
Ei4Iv#Oi`
( _3QZ
/*Created on 2005-7-15*/ ^6QzaC3
package com.adt.dao.impl; `b KJ
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import java.util.List; :{s0tw>Z
yioX^`Fc(~
import org.flyware.util.page.Page; )4R[C={
*M-'R*Np
import net.sf.hibernate.HibernateException; &fW'_,-
import net.sf.hibernate.Query; 3vHkhhYQ
}Ud'j'QMy
import com.adt.dao.UserDAO; Ce/D[%
/V }Z,'+
/** FA{'Ki`
* @author Joa meYGIP:n
*/ }t*:EgfI
public class UserDAOImpl extends BaseDAOHibernateImpl +GEdVB
X#o<))
implements UserDAO { ?
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73l,PJ
/* (non-Javadoc) ~t<uX "K
* @see com.adt.dao.UserDAO#getUserByName Fh4Exl@6
Z^c\M\`7
(java.lang.String) c-* *~tb(
*/ sD$K<nyz
publicList getUserByName(String name)throws `LNKbTc[m
b$sT`+4q
HibernateException { |j4p
String querySentence = "FROM user in class >avkiT2
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com.adt.po.User WHERE user.name=:name"; SB`xr!~A]
Query query = getSession().createQuery Y,?kS
dS
d~q7!
(querySentence); n-{.7
query.setParameter("name", name); ?u5jXJ0L
return query.list(); u%5 ,U-
} hh[x(O)TC~
_BoA&Ism
/* (non-Javadoc) ]:}7-;$V
* @see com.adt.dao.UserDAO#getUserCount() iD<}r?Z
*/ %@8#+#@J0
publicint getUserCount()throws HibernateException { C@g/{?\
int count = 0; 1'H!S%fS
String querySentence = "SELECT count(*) FROM QT=i>X
G!Yt.M0
user in class com.adt.po.User"; .O SQ8W}
Query query = getSession().createQuery o$ #q/L
t$b5,"G1
(querySentence); <Y"HCa{
count = ((Integer)query.iterate().next Z>~7|vl
:1;"{=Yx}
()).intValue(); 6]mAtA`Y
return count; Z=
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} yZ)-=H
p^w_-(p
/* (non-Javadoc) 2Vs+8/
* @see com.adt.dao.UserDAO#getUserByPage o1k+dJUd
.hjN*4RY
(org.flyware.util.page.Page) K1w:JA6(
*/
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publicList getUserByPage(Page page)throws $h[Q}uW
>-y}t9[/
HibernateException { Rq`5ff3,
String querySentence = "FROM user in class `Ue5;<K-/
,BR W=
com.adt.po.User"; 4 ]ko
Query query = getSession().createQuery 89{`GKWX
zYM0?O8pJ~
(querySentence); -XnOj2
query.setFirstResult(page.getBeginIndex()) $RYOj{1
.setMaxResults(page.getEveryPage()); R[rOzoNp0
return query.list(); FH{p1_kZ=
} {{AZW
sq@c?!'
} (w vU;u
q.j$]?PQ
C=bQ2t=Z
U;M! jj
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至此,一个完整的分页程序完成。前台的只需要调用 Sbeq%Iwm.
CdMV(
userManager.listUser(page)即可得到一个Page对象和结果集对象 x`I"%pG
FD[4?\W]#
的综合体,而传入的参数page对象则可以由前台传入,如果用 8Un0<+b
>Bu_NoM
webwork,甚至可以直接在配置文件中指定。 \odns
'Er\68
下面给出一个webwork调用示例: wh!8\9{g
java代码: ZZ/k7(8
Y~w1_>b
:
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/*Created on 2005-6-17*/ $LG.rJ/*
package com.adt.action.user; N,.awA{
.HRd6O;
import java.util.List; iBmvy7S?
B5+$VQ
import org.apache.commons.logging.Log; 9i
D&y)$"
import org.apache.commons.logging.LogFactory; v^;vH$B
import org.flyware.util.page.Page; ..w$p-1
"
t?44[
import com.adt.bo.Result; {1+meE
import com.adt.service.UserService; ":qS9vW
import com.opensymphony.xwork.Action; }h* j{b,
QU(Lv(/O
/** #V$sb1u
* @author Joa HZjuL.Tj
*/ `R!2N4|;
publicclass ListUser implementsAction{ FEX67A8/;
y|NY,{:]
privatestaticfinal Log logger = LogFactory.getLog W@i|=xS?
MO|Pv j~[
(ListUser.class); ,@I\'os
J(A+mYr{:
private UserService userService; KFy|,@NI
PZ#aq~>w
private Page page; mo,"3YW
L0w2qF
privateList users; 4G hg~0
L">m2/ HG
/* c._!dqR
* (non-Javadoc) EfkBo5@ Qi
* M:L-j{?y_
* @see com.opensymphony.xwork.Action#execute() v- p8~u1N
*/ >FJK$>[1:p
publicString execute()throwsException{ RRzLQ7J
Result result = userService.listUser(page); t~.^92]s|
page = result.getPage(); ad9u;uS
users = result.getContent(); =LEzcq>XO
return SUCCESS; eLbh1L
} a&dP@)
r{_1M>F
D!
/** >GzH_]
* @return Returns the page. T'9M
*/ qD/h/
public Page getPage(){ r"p"UW9og
return page; _X@ Q`d
} 88 ca
L(X}37
/** um\A
* @return Returns the users. Bo1 t}#7
*/ ,dFY]
publicList getUsers(){ =vDpm,
return users; l{VJaZ $M
} 07:h4beT
#-{ljjMQI
/** V343IT\
* @param page 85Kf>z::c
* The page to set. )bpdj,
*/ AgB$
w4
publicvoid setPage(Page page){ r 5+ MjR
this.page = page; %o`Cp64`Q
} #qJ6iA6{
6Q&i=!fQ
/** &4)PW\ioY
* @param users T+FlN-iy)
* The users to set. dEo r+5}
*/ zm4e+v-
publicvoid setUsers(List users){ m`b:#z
this.users = users; ie7TO{W
} Ct:c%D(L
Tz7 R:S.
/** 1{
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* @param userService q!q=axfMD
* The userService to set. ZS@R ?
*/ I;9DG8C&v*
publicvoid setUserService(UserService userService){ JD AX^]
this.userService = userService; KqNsCT+j
} f917F.1I
} k9c`[M
Xob(4
D2io3Lo$ov
}/g1
G {a;s-OA3
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 1 -R4A7+3
5j _[z|W2
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 tMo=q7ig
U]ZI_[\'U
么只需要: \tdYTb.
java代码: '[bw7T
"tj]mij2)G
[.;8GMW
<?xml version="1.0"?> cl M6R
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork -&QpQ7q1
h9~oS/%:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;:bnLSPo
("=24R=a
1.0.dtd"> ^HHT>K-m
8P2_/)|
<xwork> P{,=a]x,mz
W=,]#Z+M;
<package name="user" extends="webwork- QR$m i1Vv\
,{Z!T5 |
interceptors"> 3v)``
n@
G@<[fO|Iam
<!-- The default interceptor stack name CZ(fP86e
3p'(E\VJ
--> PW9tZx#
<default-interceptor-ref :r&4/sN}<
X"T)X#:)
name="myDefaultWebStack"/> qf%p#+:B3
+.X3&|@k
<action name="listUser" X\BdN Hr
% "ZC9uq?
class="com.adt.action.user.ListUser"> zZ8:>2Ps(
<param X
u>]$+u#
a3:1`c/~\
name="page.everyPage">10</param> D5!I{hp"
<result Q*/jQC
5"Y:^_8
name="success">/user/user_list.jsp</result> `QT9W-0e^
</action> o7yvXrpG(U
~VPE9D@
</package> `L.nj6F
Lvn+EM
</xwork>
_,*QJ
#?bOAWAwLh
2*zMLI0.
59(} D'lw>
>< Qp%yT
IpVtbDW
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 U@)WTH6d
7#9fcfL
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 CW~c<,"
;.~D!
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 :) T#.(mR
wgZ6|)!0
/tq e:*
kyUG+M
7nbaR~ZV
我写的一个用于分页的类,用了泛型了,hoho
e:6mz\J
lq)[
java代码: Kp/l2?J"
{JW_ZJx
9NqZ&S
package com.intokr.util; N\zUQ
J
sQT<I]e
import java.util.List; RIF*9= ,S
L>,xG.oG
/** M =GF@C;b
* 用于分页的类<br> wPpern05
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 3:gF4(.
* 0y/P
* @version 0.01 iM{cr&0
* @author cheng <;NxmO<%\
*/ :Y&h'FGZm
public class Paginator<E> { ;7g~4Uv4}
privateint count = 0; // 总记录数 Gk<6+.c~
privateint p = 1; // 页编号 <*djtO
privateint num = 20; // 每页的记录数 <GoZ>
privateList<E> results = null; // 结果 tnw6[U!rh=
CSMx]jbb
/** [3(lk_t
* 结果总数 R9%"Kxm
*/ N1'$;9 c
publicint getCount(){ '6Yx03t
return count; us^J!
s7
} E^V4O l<
NKRH>2,
publicvoid setCount(int count){ $(pVE}J
this.count = count; 6/L34VH
} k)S'@>n{u
}zHG]k,j
/** {OW.^UIq^
* 本结果所在的页码,从1开始 BE," lX
* t8"yAYj
* @return Returns the pageNo. qjLFgsd
*/ Ert`
]s~
publicint getP(){ DgC;1U'
return p; W/<