Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 E57{*C
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~J{[]wi
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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 !F#aodM1N
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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 wP0+Xv,
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分页支持类: '\B"g@if
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java代码: _i@eOqoC
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package com.javaeye.common.util; qU*&49X
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import java.util.List; UH-uU~
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publicclass PaginationSupport { t`ceVS
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publicfinalstaticint PAGESIZE = 30; 5qkuKF
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privateint pageSize = PAGESIZE; 0uO=wOIhH
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privateList items; Wd56B+
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privateint totalCount; e)dWa'2<
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privateint[] indexes = newint[0]; !LOors za
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privateint startIndex = 0; 33'lZubV
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public PaginationSupport(List items, int Ij}F<ZgZG
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totalCount){ TT ZxkK
setPageSize(PAGESIZE); F*JvpI[7n
setTotalCount(totalCount); (2bZ]
setItems(items); !aw#',r8m
setStartIndex(0); N^(lUba
} l()MYuLNV
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public PaginationSupport(List items, int ,,gLrVk
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totalCount, int startIndex){ J2<
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setPageSize(PAGESIZE); [7Lxt
setTotalCount(totalCount); tb?F}MEe
setItems(items); DwY<qNWT
setStartIndex(startIndex); X0Z-1bs
} -F+P;S
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public PaginationSupport(List items, int ?t0zsq
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); 3R%UPT0>
setTotalCount(totalCount); "G9'm
setItems(items); ) Zb`~w
setStartIndex(startIndex); f./m7TZ
} omv6_DdZ
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publicList getItems(){ c\)&yGE
return items; cP@F
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} f UF;SqT
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publicvoid setItems(List items){ s|gD
this.items = items; u2-@?yt
} nz(q)"A
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publicint getPageSize(){ ke9QT#~p!-
return pageSize; Fb|e]?w
} :x""E5H
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publicvoid setPageSize(int pageSize){ ?)mhJ/IT
this.pageSize = pageSize; _@/C~
} _h1 HuL
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publicint getTotalCount(){ ..]*Ao2
return totalCount; RJRq` T|m
} ?#*
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publicvoid setTotalCount(int totalCount){ 5&<d2EG6l'
if(totalCount > 0){ 3cCK"kr
this.totalCount = totalCount; @UpC{M--Wr
int count = totalCount / h-La'}>?
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pageSize; g>!:U6K
if(totalCount % pageSize > 0) 2&gd"Ak(
count++; F8[B^alAe
indexes = newint[count]; p`ADro*
for(int i = 0; i < count; i++){ S?Bc~y
indexes = pageSize * lP@)
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i; 5"kx}f2$
} S~k 0@
}else{ :J Gl>V
this.totalCount = 0; 'n^2|"$sH
} ;v,9v;T
} Jm %ynW
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publicint[] getIndexes(){ !_U37Uj<m
return indexes; [arTx^
} *U;4t/(
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publicvoid setIndexes(int[] indexes){ 'T )Or,d
this.indexes = indexes; kUn2RZ6$#
} llHc=&y#
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publicint getStartIndex(){ S9HBr
return startIndex; -}Cc"qm
} /`+Hwdk
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publicvoid setStartIndex(int startIndex){ 8ji^d1G,
if(totalCount <= 0) v}F4R $
this.startIndex = 0; &gGs) $f[
elseif(startIndex >= totalCount) 7_Ba3+9jpa
this.startIndex = indexes (]3ERPn#y
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[indexes.length - 1]; NqJ<!q)
elseif(startIndex < 0) ptV4s=G2
this.startIndex = 0; _{6,.TN
else{ ~LawF_]6
this.startIndex = indexes I!fB1aq-
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[startIndex / pageSize]; _m9~*
} b:P\=k]8#
} x7"z(rKl
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publicint getNextIndex(){ /x
int nextIndex = getStartIndex() +
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pageSize; ycgfZ 3K
if(nextIndex >= totalCount) 1@A7h$1P
return getStartIndex(); 9?uqQ
else :O9P(X*
return nextIndex; Mn]}s:v
}
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publicint getPreviousIndex(){ |}_gA
int previousIndex = getStartIndex() - H1`
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pageSize; B/jrYT$;m
if(previousIndex < 0) Ln
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return0; 9v~1We;{$
else Bj@x$v#/^
return previousIndex; <fNGhmL
} 89zuL18V
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} h ZoC _\
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抽象业务类 |]^l^e6m
java代码: R=`U 4Ml;
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/**
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* Created on 2005-7-12 <u0*"
*/ @. "q
package com.javaeye.common.business; gf+o1\5t@
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import java.io.Serializable; xb%/sz(4
import java.util.List; Ay2b,q
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import org.hibernate.Criteria; mHKJ
import org.hibernate.HibernateException; 4Mk8Cpz
import org.hibernate.Session; Y|mW.
import org.hibernate.criterion.DetachedCriteria; dIma{uv
import org.hibernate.criterion.Projections; V
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import x@htx?
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org.springframework.orm.hibernate3.HibernateCallback; eaEbH2J
import W+KF2(lB
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org.springframework.orm.hibernate3.support.HibernateDaoS O{~KR/
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upport; T-^0:@5o9
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import com.javaeye.common.util.PaginationSupport; UanEzx%
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public abstract class AbstractManager extends yKYl@&H/%
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HibernateDaoSupport { 4iwf\#
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privateboolean cacheQueries = false; iecWa:('
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privateString queryCacheRegion; GjEqU;XBi
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publicvoid setCacheQueries(boolean IAYACmlN&
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cacheQueries){ [O\9 9>
this.cacheQueries = cacheQueries; "9w}dQ
} &I%IaNco
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publicvoid setQueryCacheRegion(String ^;+[8:Kb
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queryCacheRegion){ R }1W
this.queryCacheRegion = .@@an;C
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queryCacheRegion; *#zS^b n
} m~;B:LN<
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publicvoid save(finalObject entity){ \0nlPXk?G
getHibernateTemplate().save(entity); })PO7:
} d.p'pGL
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publicvoid persist(finalObject entity){ ;=a_B1"9u
getHibernateTemplate().save(entity); 4Ac}(N5D@
} )9B:Y;>)
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publicvoid update(finalObject entity){ 1eHe~p ,
getHibernateTemplate().update(entity); i3P9sdTD
} Hs$'0:
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publicvoid delete(finalObject entity){ q4/909x=
getHibernateTemplate().delete(entity); UA0F):
} afx'
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publicObject load(finalClass entity, Kk=LXmL2
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finalSerializable id){ ya.n'X14
return getHibernateTemplate().load xz8G}Ku
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(entity, id); l[oe*aYN7
} Lc|{aN
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publicObject get(finalClass entity, T cJ$[
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finalSerializable id){ RU|X*3";T
return getHibernateTemplate().get i'=2Y9S}
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(entity, id); 'C^;OjAg
} p?JQ[K7i
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publicList findAll(finalClass entity){ >?I/;R.-
return getHibernateTemplate().find("from 5$%XvM
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" + entity.getName()); '#q4Bc1
} bY)#v?
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publicList findByNamedQuery(finalString
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namedQuery){ <( EyXV
return getHibernateTemplate wt?o
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().findByNamedQuery(namedQuery); Q+'nw9:;T
} UV@0gdy[
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publicList findByNamedQuery(finalString query, Bd#
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finalObject parameter){ E7`qmn
return getHibernateTemplate 64umul
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().findByNamedQuery(query, parameter); Q|c|2byb
} i%F<AY\O)
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publicList findByNamedQuery(finalString query, QIK
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finalObject[] parameters){ (` c
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return getHibernateTemplate :h*a
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().findByNamedQuery(query, parameters); w7
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} )/>A6A:
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publicList find(finalString query){ `5l01nOxJ
return getHibernateTemplate().find T$mbk3P
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(query); 8:dQ._#v
} 5FOqv=6S
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publicList find(finalString query, finalObject -[heV| $;
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parameter){ i=#F)AD^5#
return getHibernateTemplate().find !OAvD#
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(query, parameter); !MV@)
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} W5 ec
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public PaginationSupport findPageByCriteria JN(-.8<
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(final DetachedCriteria detachedCriteria){ BJy;-(JP
return findPageByCriteria +>tUz D
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;gB`YNL
} yWb4Ify
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public PaginationSupport findPageByCriteria ,Eu?JH&}u
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(final DetachedCriteria detachedCriteria, finalint :_HF j.JW
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startIndex){ `hUHel;6
return findPageByCriteria k ;KdW P
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(detachedCriteria, PaginationSupport.PAGESIZE, /.Q4~Hw%}
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startIndex); 5/@UVY9_
} uQ3[Jz`y
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public PaginationSupport findPageByCriteria H"Dn]$Q\Z
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(final DetachedCriteria detachedCriteria, finalint {_>em*V b
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pageSize, :]II-$/8
finalint startIndex){ NX,-;v
return(PaginationSupport) qLK?%?.N<
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getHibernateTemplate().execute(new HibernateCallback(){ X.V[0$.;
publicObject doInHibernate L:R<e#kgS
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(Session session)throws HibernateException { DL8x":;
Criteria criteria = @S3f:s0~D
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detachedCriteria.getExecutableCriteria(session); XKU=oI0\j
int totalCount = <<zI\+V
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((Integer) criteria.setProjection(Projections.rowCount vhgLcrn
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()).uniqueResult()).intValue(); 3yO=S0`
criteria.setProjection KoBW}x9Jp
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(null); {hdPhL
List items = ~Xv=9@,h
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criteria.setFirstResult(startIndex).setMaxResults w0J|u'H
\".^K5Pm
(pageSize).list(); E>uVofhml
PaginationSupport ps = 'Jj=RAV`
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new PaginationSupport(items, totalCount, pageSize, >n*\ bXf
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startIndex); N4!<Xj
return ps; [f{VIE*?%
} 4. qtp`
}, true); i$^ZTb^
} k%81f'H
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public List findAllByCriteria(final mUP. rb6
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DetachedCriteria detachedCriteria){ s8mr''
return(List) getHibernateTemplate 0L-!!
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().execute(new HibernateCallback(){ ~)]} 91p
publicObject doInHibernate 1vevEa$
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(Session session)throws HibernateException { ^{yk[tHpS
Criteria criteria = {2KFD\i\
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detachedCriteria.getExecutableCriteria(session); Dr#c)P~Wd
return criteria.list();
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} F-gE<<
}, true); =;L*<I
} uGP(R=H
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public int getCountByCriteria(final n.}T1q|l
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DetachedCriteria detachedCriteria){ +[-i%b3q
Integer count = (Integer) 5Fw - d
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getHibernateTemplate().execute(new HibernateCallback(){ ]uh3R{a/
publicObject doInHibernate LHYLC>J
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(Session session)throws HibernateException { =H`Q~Xx
Criteria criteria = _lxco=qd=%
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detachedCriteria.getExecutableCriteria(session); f'Mop= .
return ,_
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criteria.setProjection(Projections.rowCount Bi%x`4Lf
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()).uniqueResult(); `ldz`yu6++
} Me3dpF
}, true); 2DDsWJ;
return count.intValue(); \?fI t?
} }
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} %&<LNEiUN
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用户在web层构造查询条件detachedCriteria,和可选的 ['qnn|
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 YA]5~ZE\
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PaginationSupport的实例ps。 0Q9T3X
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ps.getItems()得到已分页好的结果集 6;b9swmh
ps.getIndexes()得到分页索引的数组 XP?rOOn
ps.getTotalCount()得到总结果数 E /<lGm:.
ps.getStartIndex()当前分页索引 3R$Z[D-
ps.getNextIndex()下一页索引 'Prxocxq
ps.getPreviousIndex()上一页索引 Ri*3ySyb
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Q;/a F`
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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 >]D4Q<TY
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一下代码重构了。 e /K#>,
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我把原本我的做法也提供出来供大家讨论吧: F\JUx L@8
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首先,为了实现分页查询,我封装了一个Page类: %3Z/+uT@v]
java代码: kSncZ0K{
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/*Created on 2005-4-14*/ kLSrj\6I[
package org.flyware.util.page; ?)4?V\$
y(jg#7)
/** `TLzVB-j3
* @author Joa W6c]-pc
* +K",^6%1
*/ o2H1N~e#c
publicclass Page { G@ \Pi#1
32)tJ|m
/** imply if the page has previous page */ QCOo
privateboolean hasPrePage; ^rNUAj9Z
p*QKK@C
/** imply if the page has next page */ <[ Xw)/#
privateboolean hasNextPage; A#wEuX=[
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/** the number of every page */ [I*!
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privateint everyPage; mB'3N;~
jdA
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/** the total page number */ wucV_p.E
privateint totalPage; *Nb#W!
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/** the number of current page */ LaFZ?7@|}
privateint currentPage; L71!J0@a#
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/** the begin index of the records by the current (t^n'V
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query */ [IZM.r`Z
privateint beginIndex; x[_=#8~.1x
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/** The default constructor */ UPU+ver
public Page(){ 2!1.E5.I
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} hS [SRa'.
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/** construct the page by everyPage ;!>Wz9
* @param everyPage Xf'=+f2p
* */ `(y(w-:W1
public Page(int everyPage){ p&p.Q^"ok
this.everyPage = everyPage; gJN0!N'
} Q[n\R@
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/** The whole constructor */ ={2!c0s
public Page(boolean hasPrePage, boolean hasNextPage, nwI3| &
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@LE[ac
int everyPage, int totalPage, 5/><$06rq
int currentPage, int beginIndex){ ^?"\?M1
this.hasPrePage = hasPrePage; bp<^R
this.hasNextPage = hasNextPage; /hW d/H]
this.everyPage = everyPage; !\ND(
this.totalPage = totalPage; V)M1YZV{
this.currentPage = currentPage; 5X.ebd;PT
this.beginIndex = beginIndex; % ~]xuP[
} &$FvWFRh#
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/** q(o/yx{bm
* @return 5FKBv
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* Returns the beginIndex. JNI>VP[c
*/ ?WI3/>:<
publicint getBeginIndex(){ QWnndI_4p
return beginIndex; R@Y=o].2
} MZv]s
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/** FjfN3#qlg
* @param beginIndex 9W7#u}Z
* The beginIndex to set. j|fd-<ng
*/ le)DgIT>=
publicvoid setBeginIndex(int beginIndex){ w?vVVA
this.beginIndex = beginIndex; 5MTgK=c
} Lm*VN~2
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/** I+
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* @return ^>&k]T`
* Returns the currentPage. NUJ~YWO;
*/ Wl"0m1G
publicint getCurrentPage(){ u+9<&)X0
return currentPage; bUy,5gk-
} K/_9f'^
v5ur&egVs
/** []W;t\h
* @param currentPage l3o#@sz:
* The currentPage to set. u0)7i.!M
*/ p0p4Xh1e
publicvoid setCurrentPage(int currentPage){ R0Ue0pF7
this.currentPage = currentPage; zJlQ_U- !
} Yj(4&&Q
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/** faXx4A2"
* @return Tpp &
* Returns the everyPage. ?^#lWx q
*/ N^0uit
publicint getEveryPage(){ i8X`HbmN
return everyPage; ;Q0bT`/X
} =1;=
9W`Frx'h1
/** NmIHYN3
* @param everyPage vEe NW
* The everyPage to set. 9.O8/0w7LV
*/ aT l c
publicvoid setEveryPage(int everyPage){ :c[n\)U[aa
this.everyPage = everyPage; uwIc963
} uYG^Pc^v
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/** Q/>L_S
* @return 2GmpCy`L"
* Returns the hasNextPage. mY!iu(R1
*/ ?dZt[vAMn
publicboolean getHasNextPage(){ `D5HC
return hasNextPage; I3S9Us-\
} ?NNn:t iD
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/** pY8q=Kl
* @param hasNextPage KGHq rc
* The hasNextPage to set. `em9T oJV
*/ 0o&MB
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publicvoid setHasNextPage(boolean hasNextPage){ =4!nFi
this.hasNextPage = hasNextPage; "O>n@Q|
} 1r)kR@!LNG
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/** $K~LM8_CKy
* @return oT95^y\9
* Returns the hasPrePage. E N^Uki`
*/ RuW!*LI
publicboolean getHasPrePage(){ |dE
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return hasPrePage; >cmE
t
} 9?T{}| ?
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/** BfTcI)
* @param hasPrePage /nx'Z0&+X
* The hasPrePage to set. }A$WO{2
*/ .4.pJbOg
publicvoid setHasPrePage(boolean hasPrePage){ c8 K3.&P6
this.hasPrePage = hasPrePage; 3B0lb"e
} [t]X/O3<
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/** E9!N>0
* @return Returns the totalPage. s=I'e/"7
* \g)Xt?w0Wo
*/ RH;:9_*F
publicint getTotalPage(){ g\oSG)
return totalPage; 3#kitmV
} 7Ob*Yv=[
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/** }}{!u0N},V
* @param totalPage 6"j_iB
* The totalPage to set. {.e=qQ%P5)
*/ Wk;5/
publicvoid setTotalPage(int totalPage){ Pj#'}ru!
this.totalPage = totalPage; {y
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} XV>JD/K2
Y OyX[&oi
} rPzQ8<
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ug 7o>PX
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 XdEPbD-
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个PageUtil,负责对Page对象进行构造: ^W83ByP
java代码: 7iC *Pr
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/*Created on 2005-4-14*/ 3.
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package org.flyware.util.page; 8U2dcx:G3
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import org.apache.commons.logging.Log; n_K~vD
import org.apache.commons.logging.LogFactory; T>>YNaUL
:Gqy>)CxX
/** Tn-C>=tR~%
* @author Joa DdV'c@rq+
* C2e.2)y
*/ F-Z%6O,2
publicclass PageUtil { ?^HfNp9
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privatestaticfinal Log logger = LogFactory.getLog _K2?YY(#>
"T/>d%O1b
(PageUtil.class); lw%?z/HDf
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/** !,$i6gm
* Use the origin page to create a new page 1nj(hg
* @param page `<\}FS`'
* @param totalRecords <T?oKOD ]
* @return OqhD7 +
*/ H!e 3~+)
publicstatic Page createPage(Page page, int >P KBo
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totalRecords){ VUU]Pu &
return createPage(page.getEveryPage(), \79X{mcd
*2"6fX[
page.getCurrentPage(), totalRecords); rk2xKm^w
} PrF}a<:n:
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/** s)A<=)w/e
* the basic page utils not including exception %u{W7
JD>d\z2QC
handler i yYJR
* @param everyPage mbl]>JsQD
* @param currentPage y2HxP_s?P?
* @param totalRecords = 64r:E
* @return page Eq%@"-mo
*/ D,l,`jv*
publicstatic Page createPage(int everyPage, int fr6^nDY
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currentPage, int totalRecords){ ~0"p*?^
everyPage = getEveryPage(everyPage); N8cAqr
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, *TW=/+j
KP;(Q+qTx
currentPage); Huw\&E
int totalPage = getTotalPage(everyPage, }'"Gr%jf(
0x2!<z
totalRecords); 7"X>?@
boolean hasNextPage = hasNextPage(currentPage, n]W_e
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totalPage); SM 0M%
boolean hasPrePage = hasPrePage(currentPage); 5`/@N{e
x LBQ
returnnew Page(hasPrePage, hasNextPage, 1&=0Wg0ig
everyPage, totalPage, qr\!*\9
currentPage, I<b?vR 'F
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beginIndex); ij5g^{_T;8
} 8$N8}q%
NMO-u3<6.
privatestaticint getEveryPage(int everyPage){ w
JwX[\
return everyPage == 0 ? 10 : everyPage; $Kj&)&M
} Z[!d*O%R_
Ey{%XR+*;
privatestaticint getCurrentPage(int currentPage){ 1iT\df
return currentPage == 0 ? 1 : currentPage; 23(=Xp3;>
} >Y 1{rSk
K[\'"HyQ,X
privatestaticint getBeginIndex(int everyPage, int -u!qrJ*Z
stl 1QO(h
currentPage){ c47")2/yO
return(currentPage - 1) * everyPage; T Zir>5
} ^62|d
Rr(* aC2P
privatestaticint getTotalPage(int everyPage, int +!-~yf#RE
h~U02"$
totalRecords){ {MAQ/5
int totalPage = 0; ;32#t[ib
Ax3W2s
if(totalRecords % everyPage == 0) `7aDEzmJ
totalPage = totalRecords / everyPage; y]..=z_ql
else >C WKH~
totalPage = totalRecords / everyPage + 1 ; 5(2|tJw-H;
'+'CbWgY
return totalPage; <<9Va.
} d<w~jP\
( fD
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privatestaticboolean hasPrePage(int currentPage){ 'J*<iA*W
return currentPage == 1 ? false : true; BIaDY<j90
} c9' '
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)R
privatestaticboolean hasNextPage(int currentPage, Uv_N x10
PMs z`
int totalPage){ XB hb`AG
return currentPage == totalPage || totalPage == k@>\LR/v
yDb'7(3-
0 ? false : true; >e5 *prx+
} !U_K&f
sH,kW|D
/z7VNkD
} m4k
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o{v&.z
+1C3`0(
wyx(FinIH
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。 $VG*q
<[aDo%,A
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 qpoV]#iW
%x;x_
做法如下: =M 6[URZ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象
r#PMy$7L
Hi!Jj
的信息,和一个结果集List: 80}+MWdo
java代码: "}WJd$
o 6 {\Zzp
Bsf7mcXz7z
/*Created on 2005-6-13*/ pN6%&@) =
package com.adt.bo; x"kjs.d7[<
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import java.util.List; -kz4FS
{>3\N0e5
import org.flyware.util.page.Page; |s7`F%
)'4P.>!!aQ
/** rsn.4P=
* @author Joa (w(
*/ RhI;;Y#@
publicclass Result { uy _wp^
cxeghy:;U
private Page page; 3:/'t{ ^B
:6 J +%(f
private List content; i>L+gLW
Uk*IpP`
/** i
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* The default constructor +.B<Hd
*/ t9gfU5?
public Result(){ :pX`?Ew`g
super(); r'LVa6e"N
} '[|+aJ
zr v]
/** x} /,yaWZ
* The constructor using fields uhH^>z
KA
* Zd^6ulx
* @param page DF]9@{
* @param content j*@l"V>~
*/ [sV"ws
public Result(Page page, List content){ V!%jf:k
this.page = page; IH48|sa
this.content = content; ~\p]~qQ\K
} ] H~4
b2(RpY2Y
/** a?}
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* @return Returns the content. 0l*]L`]L#
*/ w1x"
c>1C
publicList getContent(){ 'k;4 j|<
return content; B0$:b!
} sKz`aqI
>%p{38
/** !1T\cS#1%
* @return Returns the page. MfO:m[s
*/ 7`vEe'qz
public Page getPage(){ 8*SDiZ
return page; _8fr6tO+
} )C(>H93
NqHy%'R
/** {_N,=DQ!
* @param content 5IOFSy`
* The content to set. #?MY&hdU9
*/ JTqDr
public void setContent(List content){ _iKq~\v2
this.content = content; HD,xY4q&N
} _LP/!D
X)SDG#&+bF
/** 3P~o"a>
* @param page
j1?j6s
* The page to set. .M,RFC
*/ ~"pKe~h
publicvoid setPage(Page page){ I&?Qq k
this.page = page; Xdi:1wW@p
} B!{d-gb
} ~ *:F{
6K
cD&S/
g,`A[z2
Vt^3iX{!
2 &/v]
2. 编写业务逻辑接口,并实现它(UserManager,
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UserManagerImpl) 0.$hn
java代码: Rtb :nJ8
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M7f;Pa
/*Created on 2005-7-15*/ #ywk|k5z]
package com.adt.service; bn
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J{ [n?/A{
import net.sf.hibernate.HibernateException; 7e7 M@8+4
=/<LSeLxH
import org.flyware.util.page.Page; T@}|zDC#
.)1_Ew
import com.adt.bo.Result; hPq%Lc
kdz=ltw
/** -?]W*f
* @author Joa #QCphhG
*/ &1%q"\VI
publicinterface UserManager { O/:UJ( e{
)%rg?lI
public Result listUser(Page page)throws G;>
_<22
*"9><lJ-!
HibernateException; 6cqP2!~
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} l1ZY1#%j
PcB_oG g
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|+ N5z
java代码: ) 9,
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/*Created on 2005-7-15*/ zYXV;
package com.adt.service.impl; f}guv~K
=U|N=/y#hJ
import java.util.List; 1+b{}d
N@B9
@8h
import net.sf.hibernate.HibernateException; r"$.4@gc
.xf<=ep
import org.flyware.util.page.Page; [c_|ob]
import org.flyware.util.page.PageUtil; E{6~oZ#L
(}. @b|s
import com.adt.bo.Result; Y*_)h\f
import com.adt.dao.UserDAO; <2C7<7{7
import com.adt.exception.ObjectNotFoundException; A+@&"
import com.adt.service.UserManager; rt
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/** NvM*h%ChM
* @author Joa zByT$P-
*/ ceNix!P
publicclass UserManagerImpl implements UserManager { B^).BQ
aq7~QX_0G
private UserDAO userDAO; "3FihE]k
5s(1[(
/** 5SCKP<rb
* @param userDAO The userDAO to set. JNcYJ[wqv
*/ j}b\Z9)!
publicvoid setUserDAO(UserDAO userDAO){ QMv@:Eo
this.userDAO = userDAO; lRh9j l
} Uye|9/w8 !
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/* (non-Javadoc) Wg`R_>qQSm
* @see com.adt.service.UserManager#listUser ZiLj=bh
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(org.flyware.util.page.Page) (8_\^jJ
*/ h6dPO"
public Result listUser(Page page)throws Y^<bl2"y8
+{sqcr1G
HibernateException, ObjectNotFoundException { 5nbEf9&
int totalRecords = userDAO.getUserCount(); {Ay"bjZh
if(totalRecords == 0) P2Vg 4
throw new ObjectNotFoundException s+tGFjq
OtFh,}E
("userNotExist"); zbJT&@z
page = PageUtil.createPage(page, totalRecords); .s$z/Jv
List users = userDAO.getUserByPage(page); D7_*k%;@
returnnew Result(page, users); VK@!lJu!
} Q1@A2+ c
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} k4 F"'N
Cu6%h>@K$
$1SUU F\.
TX
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 e{Z &d
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询,接下来编写UserDAO的代码: <FZ@Q[RP
3. UserDAO 和 UserDAOImpl: hB{jUP)";
java代码: K\|FQ^#UYm
Ar~"R4!
HaIM#R32T
/*Created on 2005-7-15*/ qWw\_S
package com.adt.dao; $AHQmyg<
-_$$Te
import java.util.List; (5\NB0
tDUwy^j
import org.flyware.util.page.Page; O$4yAaD
X
>LDhU%bH
import net.sf.hibernate.HibernateException; ?7{H|sI
eF2|Wjl``;
/** qWb+r
* @author Joa =*Bl|;>6
*/ /*0K92NB
publicinterface UserDAO extends BaseDAO { 7`u$
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publicList getUserByName(String name)throws $M Jm*6h
X1~1&:V,<
HibernateException; DK}"b}Fvq
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publicint getUserCount()throws HibernateException; {T].]7Z
D= 7c(
publicList getUserByPage(Page page)throws >t7x>_~
$tl\UH7%2
HibernateException; F:a ILx
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} z;y:9l
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IsR!'%Pu
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Kv~U6_=1O
java代码: _o8?E&d
o=1X^,
/&4U6a
/*Created on 2005-7-15*/ )m. 4i =X
package com.adt.dao.impl; 7B?c{
Pi|o` d
import java.util.List; =9T$Gr
64
5z#_}C$
import org.flyware.util.page.Page; 8U_{|]M
W6Y@U$P#G
import net.sf.hibernate.HibernateException; D+>1]ij
import net.sf.hibernate.Query; 0iJue&
|ZQ@fmvL/p
import com.adt.dao.UserDAO; X]'7Ov
,~._}E&9I
/** %; D.vKoh
* @author Joa i7ly[6{^pr
*/ B/n[m@O
public class UserDAOImpl extends BaseDAOHibernateImpl V dn&c
IH"6? 9nd
implements UserDAO { Nv"EV;$
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/* (non-Javadoc) :<|<|qJWo
* @see com.adt.dao.UserDAO#getUserByName `He,p -
$cZUM}@
(java.lang.String) [pM V?a[
*/
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publicList getUserByName(String name)throws KI+VXH}Y5{
,GgAsj: K
HibernateException { L31|\x]
String querySentence = "FROM user in class 9HX =T%
0P]E6hWgg
com.adt.po.User WHERE user.name=:name"; Pfs;0}h5
Query query = getSession().createQuery M.>l#4s,'
Nr=d<Us9f
(querySentence); Ox-|JJ=
query.setParameter("name", name); y\x+
return query.list(); 3*@5S]]
} ^urDoB:
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/* (non-Javadoc) y.q(vzg\_
* @see com.adt.dao.UserDAO#getUserCount() x+]\1p
*/ s8h-,@p
publicint getUserCount()throws HibernateException { )K2HK&t:
int count = 0; &
j+oJasI
String querySentence = "SELECT count(*) FROM b3VS\[p
-!
K-Htb-
user in class com.adt.po.User"; /S lYm-uQ+
Query query = getSession().createQuery 1PatH[T[
{,L+1h
(querySentence); jkvgoxY
count = ((Integer)query.iterate().next tzh1s
i
nb>7UN.9
()).intValue(); ivz{L-
return count; -(b kr+N
} <Z/x,-^*<
r4#o+qE
/* (non-Javadoc) Ggb5K8D*
* @see com.adt.dao.UserDAO#getUserByPage NG6& :4!
.AU)*7Gh
(org.flyware.util.page.Page) ',S'.U
*/ JGQj w(Xs
publicList getUserByPage(Page page)throws *H|M;G
`F>O; >i''
HibernateException { fX|Y;S-@+
String querySentence = "FROM user in class >_LDMs[-p
Tq4-wE+
com.adt.po.User"; W='>:H
Query query = getSession().createQuery U,.![TP
z+>}RT]
(querySentence); WH\))y-
query.setFirstResult(page.getBeginIndex()) nxl[d\ap+n
.setMaxResults(page.getEveryPage()); VZl6t;cn
return query.list(); +) m_o"hl
} Pp5^@A
lO_UPC\@fw
} %p0xM
{qa Aq%'
@#-q^}3
<(-hx+^
/n8B,-Z5s5
至此,一个完整的分页程序完成。前台的只需要调用 '3 ^+{=q
yiA<,!;4P
userManager.listUser(page)即可得到一个Page对象和结果集对象 _:"<[ >9
,xx R\}
的综合体,而传入的参数page对象则可以由前台传入,如果用 9\DQ>V TQ
`9b7>Nn<
webwork,甚至可以直接在配置文件中指定。 `kJ^zw+
`{xNXH]@
下面给出一个webwork调用示例: +o51x'Ld*
java代码: O7 $hYk
~7Tc$
"I
6efnxxY}sa
/*Created on 2005-6-17*/ X7g1:L1Ys
package com.adt.action.user; G"XVn~]
VH1d$
import java.util.List; =>! Y{:
y(
'^"6+ k
import org.apache.commons.logging.Log; X.e7A/ClEo
import org.apache.commons.logging.LogFactory; 5>\/[I/!
import org.flyware.util.page.Page; [E
] E
c*@E_}C#
import com.adt.bo.Result; g'm+/pU)w)
import com.adt.service.UserService; #*(td<Cp
import com.opensymphony.xwork.Action; aqc?pqM
v3jg~"!
/** $"H{4x`-
* @author Joa E 0?iXSJ
*/ ])!o5`ltZ
publicclass ListUser implementsAction{ a0ObBe'
7[}xP#Z
privatestaticfinal Log logger = LogFactory.getLog KPj\-g'A
=HlQ36;*
(ListUser.class); X]dwX%:Z!j
!f+H,]D"
private UserService userService; 9amaL~m
C-H@8p?T
private Page page; `u&Zrdr,
gjAIEI
privateList users; ixT:)|'i
~'CE[G5
/* XUlS\CH@{
* (non-Javadoc) Uh):b%bS;J
* 9
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* @see com.opensymphony.xwork.Action#execute() rq/I` :
*/ fL=~NC"
publicString execute()throwsException{ -B$2\ZE
Result result = userService.listUser(page); jyZWVL:_
page = result.getPage(); 9AJ7h9L
users = result.getContent(); 8{X"h#
return SUCCESS; 3^6
d]f
} ikSt"}/hd
-xA2pYz"
/** T]=r Co
* @return Returns the page. +lMX{es\O
*/ Y1J=3Y
public Page getPage(){ A"rfZ`
return page; LpqO{#ZG
}
ftF@Wq1f
/
:n#`o=;
/** u2?|Ue@[
* @return Returns the users. #odI EC/
*/ ,~]tg77
publicList getUsers(){ %s(k_|G+4
return users; "pRtczxOgR
} b7p@Dn?E
aD$v2)RR
/** S_IUV)
* @param page TmV,&['mg
* The page to set. 4QIX19{"
*/ G%W8S
\
publicvoid setPage(Page page){ /Y7<5!cS
this.page = page; PU^l.
} n74V|b6W
lUvpszH=
/** )j0TeE1R
* @param users In<n&ib
* The users to set. m~-K[+ya`D
*/ m1Mt#@,$
publicvoid setUsers(List users){ 1R1z
this.users = users; n' q4
} S9~+c
&b%zQ4%d-`
/** PC-"gi=h
* @param userService +2&@x=xy
* The userService to set. a+Kj1ix
*/ N%*5 T[.
publicvoid setUserService(UserService userService){ j+uLV{~g6
this.userService = userService; P<a)25be/
} jT]0WS-b
} :6 Lx@
Yd=>K HVD
sEGO2xeI
.@@?Pj?)
ov_j4j>6P
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, [8=vv7wS
? -dX`n
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 6&