Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 P<@V
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 D`2c61jyc
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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 IO x9".
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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 WML%yO\.;
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分页支持类: b3z{FP
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java代码: CXr]V"X9
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package com.javaeye.common.util; 1I*b7t
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import java.util.List; D)ZGTq`(
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publicclass PaginationSupport { ahno$[
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publicfinalstaticint PAGESIZE = 30; Q,#
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privateint pageSize = PAGESIZE; u!FX 0Ip
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privateList items; y Q_lJIX
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privateint totalCount; J_]B,'
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privateint[] indexes = newint[0]; #-wtNM%1#
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privateint startIndex = 0; mT@8(
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public PaginationSupport(List items, int 9%i|_c}
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totalCount){ xWv@PqXD
setPageSize(PAGESIZE); $n30[P@p;
setTotalCount(totalCount); 3_:J`xX(4
setItems(items); D\}A{I92F4
setStartIndex(0); TmZ%
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} e_Ue9c.}
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public PaginationSupport(List items, int Flrpk`4
HB}!Lf#*P
totalCount, int startIndex){ .""?k[f5Q
setPageSize(PAGESIZE); dX4"o?KD>
setTotalCount(totalCount); 2E
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setItems(items); 2m]CmdV^
setStartIndex(startIndex); afVl)2h
} n2NxO0
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public PaginationSupport(List items, int 3dlL?+Y#
}IM *Vsk
totalCount, int pageSize, int startIndex){ \t6k(5J
setPageSize(pageSize); RqV* O}Am
setTotalCount(totalCount); ,P&.qg i=(
setItems(items); ?U\@?@
setStartIndex(startIndex); AATiI+\S
} Ifghyh<d
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publicList getItems(){ noali96J
return items; O_yk<
} q97Z .o
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publicvoid setItems(List items){ ?Vy%<f$
this.items = items; lV4|(NQ9
} Z2HH&3HA
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publicint getPageSize(){ MN wMF
return pageSize; {tq.c9+!d
} bq mb|mD
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publicvoid setPageSize(int pageSize){ s4RqY*VK
this.pageSize = pageSize; ]kXiT Yg
} rHzwSR@}1
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publicint getTotalCount(){ ?<YQ
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return totalCount; z}'-gv\,
} {h<V^r
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publicvoid setTotalCount(int totalCount){ `eD70h`XK
if(totalCount > 0){ 5crd.1@^
this.totalCount = totalCount; 0X.(BRI~6p
int count = totalCount / eXB'>#&s
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pageSize; !'y9/
if(totalCount % pageSize > 0) 2pKkg>/S
count++; :gD=F &V
indexes = newint[count]; U3R;'80 f
for(int i = 0; i < count; i++){ MLbmz\8a
indexes = pageSize * 5G
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i; k0@b"y*
} P2U^%_~
}else{ b0QC91
this.totalCount = 0; >(>,*zP<9
} >iZ"#1ZL2O
} .uo9VL<
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publicint[] getIndexes(){ _h?hFs,N]
return indexes; u,E_Ezq
} 9L2]PU
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publicvoid setIndexes(int[] indexes){ mE|?0mRA %
this.indexes = indexes; /6K9? /
} SauX C
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publicint getStartIndex(){ Mj9Mv<io
return startIndex; G+?Z=A:T8
} <D_UF1Pk
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publicvoid setStartIndex(int startIndex){ ,QB]y|:
if(totalCount <= 0) Fv| )[>z0
this.startIndex = 0; 0bl?dOV{
elseif(startIndex >= totalCount) S2;u!f
this.startIndex = indexes \
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[indexes.length - 1]; d[0R#2y=
elseif(startIndex < 0) xtWwz}^8]
this.startIndex = 0; )#(6J
else{ zwLJ|>
this.startIndex = indexes C2X$ bX"
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[startIndex / pageSize]; })V^t3
} IqA'Vz,lL
} b.N$eJlQ&
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publicint getNextIndex(){ f/?uosS
int nextIndex = getStartIndex() + 6Z}8"VJr {
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pageSize; m }J@w~#
if(nextIndex >= totalCount) w
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return getStartIndex(); vtA%^~0
else =._V$:a6o
return nextIndex; ~W>3EJghR,
} Bu ]PNKIi
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publicint getPreviousIndex(){ s"'ns
int previousIndex = getStartIndex() - Rj'Tu0l
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pageSize; @mD$Z09~
if(previousIndex < 0) hI$IBf>
return0; -eQ>3x&3r
else f>!H<4
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return previousIndex; +u[^@>_I0
} Pg''>6w>
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} -4;$NiB?
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抽象业务类 x+Ws lN2a
java代码: : Yb_
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/** 83i;:cn
* Created on 2005-7-12 Jv8JCu"eky
*/ )wM881_!
package com.javaeye.common.business; )w_hbU_Pb&
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import java.io.Serializable; 75"&"*R/*G
import java.util.List; >53Hqzm&
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import org.hibernate.Criteria; /a .XWfu
import org.hibernate.HibernateException; {Qf/.[
import org.hibernate.Session; 9< |nJt
import org.hibernate.criterion.DetachedCriteria; H"; !A=0
import org.hibernate.criterion.Projections; l:.q1UV
import Ai*+LSG
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org.springframework.orm.hibernate3.HibernateCallback; JYK4/gJ
import EJid@
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org.springframework.orm.hibernate3.support.HibernateDaoS %_L~"E 2e
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upport; INRP@Cp1
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import com.javaeye.common.util.PaginationSupport; 8+n*S$
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public abstract class AbstractManager extends [sXnB$
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HibernateDaoSupport { wZs jbNf`K
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privateboolean cacheQueries = false; $lAQcG&Q
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privateString queryCacheRegion; b(Nxk2uv
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publicvoid setCacheQueries(boolean g/W&Ap;qVL
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cacheQueries){ Ge=|RAw3
this.cacheQueries = cacheQueries; )~{8C:
} *?x[pqGq
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publicvoid setQueryCacheRegion(String 9&"wfN N
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queryCacheRegion){ A5IW[Gu!
this.queryCacheRegion = w\}Q.$@
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queryCacheRegion; O|mWQp^?q
} p_EWpSOt7
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publicvoid save(finalObject entity){ 5`FPv4
getHibernateTemplate().save(entity); *s%M!YM
} 9!,f4&G`
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publicvoid persist(finalObject entity){ G\B:iyKl
getHibernateTemplate().save(entity); IWT
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} !a7YM4D
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publicvoid update(finalObject entity){ 0/JTbf. CX
getHibernateTemplate().update(entity); lbj_if;
} swfjKBfw+g
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publicvoid delete(finalObject entity){ ~0YRWM ;
getHibernateTemplate().delete(entity); `OHdo$Y9
} 'EO"0,
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publicObject load(finalClass entity,
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finalSerializable id){ ZJ%iiY
return getHibernateTemplate().load 0I}c|V'P
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(entity, id); [u;>b?[{
} 1$nuh@-ys
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publicObject get(finalClass entity, =p \eh?^
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finalSerializable id){ F
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return getHibernateTemplate().get NI2-*G_M
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(entity, id); =PmIrvr'[5
} N 8pzs"
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publicList findAll(finalClass entity){ . sv
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return getHibernateTemplate().find("from 9D
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" + entity.getName()); '=(@3ggA:
} "rcV?5?v~
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publicList findByNamedQuery(finalString |Li9Y"5
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namedQuery){ Eikt,
return getHibernateTemplate K j6@=
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().findByNamedQuery(namedQuery); }3S6TJ+
} $c];&)7q
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publicList findByNamedQuery(finalString query, 8C5*: x9l
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finalObject parameter){ hEfFMi=a`
return getHibernateTemplate Z#flu Q%V
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().findByNamedQuery(query, parameter); T-.Bof(?w
} jWGX:XB
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publicList findByNamedQuery(finalString query, wyUfmk_}
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finalObject[] parameters){ ^03M~SNCj
return getHibernateTemplate DX<xkS[P
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().findByNamedQuery(query, parameters); 7s2e>6Q[
} ZnRE:=
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publicList find(finalString query){ d^G5Pq
return getHibernateTemplate().find iYl{V']A
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(query); 2VgVn,c
} '9Xw_1B
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publicList find(finalString query, finalObject QUi=ZD1
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parameter){ fR,7l9<%Zp
return getHibernateTemplate().find 9I*i/fa
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(query, parameter); cQ`+ A|q
} 0r ilg
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public PaginationSupport findPageByCriteria cB2jf</
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(final DetachedCriteria detachedCriteria){ K&%YTA
return findPageByCriteria 9 p`|~^X
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \++#adN:K
} W*Ce1
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public PaginationSupport findPageByCriteria Q=.j>aM+_
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(final DetachedCriteria detachedCriteria, finalint .6y(ox|LL
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startIndex){ tzSg`7H!
return findPageByCriteria ?KXgG'!!
& <Jvaf_=
(detachedCriteria, PaginationSupport.PAGESIZE, 9|&%"~6'
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startIndex); Y)9]I6n7
} =RQ\i6Y
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public PaginationSupport findPageByCriteria @P
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(final DetachedCriteria detachedCriteria, finalint 7Hp~:i30
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pageSize, te8lF{R
finalint startIndex){ l@nG?l #
return(PaginationSupport) 7|$
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getHibernateTemplate().execute(new HibernateCallback(){ jBnvu@K "
publicObject doInHibernate x#&%lJT
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(Session session)throws HibernateException { ]QK@zb}x
Criteria criteria = "T'?Ah6
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detachedCriteria.getExecutableCriteria(session); SBqx_4}
int totalCount = Q.`O;D}x
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((Integer) criteria.setProjection(Projections.rowCount 8A3!XA
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()).uniqueResult()).intValue(); Q]2v]PJ6"
criteria.setProjection bx8|_K*^
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(null); @(Y+W2Iyy+
List items = tx01*2]pX
}!0nb)kL
criteria.setFirstResult(startIndex).setMaxResults _b1w<T
`
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(pageSize).list(); K h;jiK !
PaginationSupport ps = =_Y#uE$
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new PaginationSupport(items, totalCount, pageSize, =a3qpPkx
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startIndex); =lqBRut
return ps; jM DG
} wa}\bNKQk
}, true); YQk<1./}I
} SUQk0 (M
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public List findAllByCriteria(final :D !}jN/)
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DetachedCriteria detachedCriteria){ K=mW`XXup
return(List) getHibernateTemplate h(VF
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().execute(new HibernateCallback(){ W2\Q-4D
publicObject doInHibernate TWFi.w4pY
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(Session session)throws HibernateException { Sx%vJYH0
Criteria criteria = Sxw%6Va]p
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detachedCriteria.getExecutableCriteria(session); "O,TL*$
return criteria.list(); Q\4nduQ
} NiTLQ"~e
}, true); (`pd>
} EO[UezuU
@hE$x-TP0
public int getCountByCriteria(final HX]pcX^K
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DetachedCriteria detachedCriteria){ A&~<qgBTp
Integer count = (Integer) E6NrBPm
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getHibernateTemplate().execute(new HibernateCallback(){ 7>Oa, \
publicObject doInHibernate |:?JSi0
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(Session session)throws HibernateException { $2j?Z.yEG
Criteria criteria = 47c` ) *Hc
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detachedCriteria.getExecutableCriteria(session); k TLA["<m
return !z.C}n5F
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criteria.setProjection(Projections.rowCount j4B|ktf
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()).uniqueResult(); =_/,C
} ? <.U,
}, true); _+\hDV>v
return count.intValue(); 8v)PDO~D}A
} uJP9J U
} `RG_FS"v
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用户在web层构造查询条件detachedCriteria,和可选的 j`9+pI
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 z!={d1u#T
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PaginationSupport的实例ps。 kM`!'0kt
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ps.getItems()得到已分页好的结果集 \5wC&|WEB
ps.getIndexes()得到分页索引的数组 :%?\Wj5HW
ps.getTotalCount()得到总结果数 mQOYjy3
ps.getStartIndex()当前分页索引 fJ?$Z|
ps.getNextIndex()下一页索引 /_rg*y*
ps.getPreviousIndex()上一页索引 vh~:{akR
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 hupYiI~
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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 cN> z`xl
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一下代码重构了。 hal3J
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我把原本我的做法也提供出来供大家讨论吧: "KY9MBzPD
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首先,为了实现分页查询,我封装了一个Page类: o6$Q>g`]
java代码: 3f{%IU(z
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/*Created on 2005-4-14*/ FshQ OFW
package org.flyware.util.page; z90=,wd
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/** ~lR"3z_Z}
* @author Joa VvwQz#S
* "/).:9],}
*/ 9^m& [Z
publicclass Page { 4:=eO!6
`nO!_3
/** imply if the page has previous page */ MR90 }wXE
privateboolean hasPrePage; 4=H/-v'&
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/** imply if the page has next page */ /:a~;i
privateboolean hasNextPage; 4ifWNL^)
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/** the number of every page */ {)eV) 2a
privateint everyPage; ;a+>><x]
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/** the total page number */ W39R)sra
privateint totalPage; ms=Ilz
#;
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/** the number of current page */ rs@,<DV)u
privateint currentPage; wovWEtVBU
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/** the begin index of the records by the current $cev,OW6]
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query */ 7
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privateint beginIndex; DTdL|x.{
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/** The default constructor */ z(^p@&r)F
public Page(){ U~SK 'R
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} S:] w@$
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/** construct the page by everyPage EIl _QV6
* @param everyPage a%f5dj+
* */ m=2TzLVv
public Page(int everyPage){ VGBL<X
this.everyPage = everyPage; }k}5\%#li5
} l[^bo/
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/** The whole constructor */ Q]7Q4U
public Page(boolean hasPrePage, boolean hasNextPage, _OT kv6;4n
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int everyPage, int totalPage, /Mf45U<
int currentPage, int beginIndex){ LiJ;A*
this.hasPrePage = hasPrePage; io:?JnQSA
this.hasNextPage = hasNextPage; Gq;0j:?CC
this.everyPage = everyPage; T7n;Bf
this.totalPage = totalPage; K/Axojo
this.currentPage = currentPage; G7C9FV bR
this.beginIndex = beginIndex; +v&+8S`+
} Hux#v>e
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/** 3}$L4U
* @return &%J{C3Q9
* Returns the beginIndex. |mrAvm}
*/ lp?geav
publicint getBeginIndex(){ 2o/}GIKj
return beginIndex; W"|89\p}
} FFtj5e
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/** THK)G2
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* @param beginIndex ms3Ec`i9
* The beginIndex to set. vVKiE 6^
*/ 1O9V Ej5
publicvoid setBeginIndex(int beginIndex){ \VPU)
this.beginIndex = beginIndex; +(r8SnRX
} jKQnox+=
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/** g}' "&Y
* @return LP_!g
* Returns the currentPage. RXgi>Hz
*/ Q=~e|
publicint getCurrentPage(){ Oa7`Y`6
return currentPage; L4SFu.J'
} z-(dT
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/** k`.-PU
* @param currentPage fYx$3a.
* The currentPage to set. m+DkO{8F
*/ WJe
publicvoid setCurrentPage(int currentPage){ vyqlP;K
this.currentPage = currentPage; ^l_W9s
}
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/** J_U1eSz<j
* @return Cb.~Dv
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* Returns the everyPage. y"!+Fus9
*/ ykl./uY'
publicint getEveryPage(){ 1NN99^q
return everyPage; "v jFL9
} yBauK-7*c
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/** ^b;.zhp8;N
* @param everyPage -YHlVz
* The everyPage to set. ,/:#=TuYm
*/ lpve Yz
publicvoid setEveryPage(int everyPage){ d'^jekh
this.everyPage = everyPage; |;{wy
} .'+Tnu(5q
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/** v.\1-Q?
* @return bbiDY
* Returns the hasNextPage. $}W=O:L+D
*/ ;% !'K~
publicboolean getHasNextPage(){ nd_d tsp#
return hasNextPage; GRO[&;d`
} +n^$4f
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/** "=9L7.E)
* @param hasNextPage ?KI_>{
* The hasNextPage to set. |nz,srr~
*/ hXbb+j
publicvoid setHasNextPage(boolean hasNextPage){ vlm&)DIt
this.hasNextPage = hasNextPage; "-A@>*g
} RjSVa.x
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/** *Yl9%x]3c
* @return "J%u
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* Returns the hasPrePage. _hA p@?
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*/ OPBnU@=R
publicboolean getHasPrePage(){ q%Obrk
return hasPrePage; hM/|k0YV
} J'b*^K
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/** &'c1"%*%8>
* @param hasPrePage >UZfi u
* The hasPrePage to set. m}Kn!21
*/ 5RI"gf
publicvoid setHasPrePage(boolean hasPrePage){ <.s[x~b\`
this.hasPrePage = hasPrePage; vDv:3qN7(
} jUI'F4.5x-
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/** B Lw ssr.
* @return Returns the totalPage. [[Qu|?KEa
* ZnI_<iFR*
*/ F^3Q0KsT
publicint getTotalPage(){ a%7%NN*i
return totalPage; jzdK''CHi
} dilRL,
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/** *s S7^OZ*
* @param totalPage %W+*)u72(
* The totalPage to set. !d&K,k
*/ z6ArSLlZ
publicvoid setTotalPage(int totalPage){ )(_}60
this.totalPage = totalPage; x =5k74
} M@E*_U!U
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} l}5@6;}
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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 5|9,S
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个PageUtil,负责对Page对象进行构造: ]xCJ3.9
java代码: -s,^_p{H
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/*Created on 2005-4-14*/ KArR.o }
package org.flyware.util.page; _K_!(]t
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import org.apache.commons.logging.Log; (UAa
import org.apache.commons.logging.LogFactory; C~yfuPr\B
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/** |Eu_K`
* @author Joa bT|a]b:
* /![S 3Ol
*/ -sh S?kV
publicclass PageUtil { ZXY5Xvt:v
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privatestaticfinal Log logger = LogFactory.getLog i"_)91RA
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(PageUtil.class); G{pfyfF
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/** P|!GXkS
* Use the origin page to create a new page `kpX}cKK}
* @param page `M6!V
* @param totalRecords hJ (Q^Z
* @return 1j`-lD
*/ Q&opnvN
publicstatic Page createPage(Page page, int lQ<2Vw#Yl
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totalRecords){ =!*e; L
return createPage(page.getEveryPage(), j#f+0
N /p9Ws
page.getCurrentPage(), totalRecords); 2%m H
} 0~iC#lHO
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/** eB%KXPhMm
* the basic page utils not including exception AE={P*g
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handler w9rwuk
* @param everyPage h3Nwxj~E
* @param currentPage @{iws@.
* @param totalRecords Kyt.[" p
* @return page 1XSA3;ZEc
*/ WS/^WxRY
publicstatic Page createPage(int everyPage, int /`Yy(?,
5Q#;4
currentPage, int totalRecords){ Kfa7}f_
everyPage = getEveryPage(everyPage); Wb+^Ue
currentPage = getCurrentPage(currentPage); #=V%S
2~
int beginIndex = getBeginIndex(everyPage, +dX1`%RR[
6}='/d-[
currentPage); MUhC6s\F
int totalPage = getTotalPage(everyPage, 4v_?i@,L
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totalRecords); F l83
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boolean hasNextPage = hasNextPage(currentPage, / *RDy!m
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totalPage); orVsMT[A
boolean hasPrePage = hasPrePage(currentPage); b'Pq[ )
4.I6%Bq$
returnnew Page(hasPrePage, hasNextPage, q#:,6HDd
everyPage, totalPage, H%t/-'U?
currentPage, O$k;p<?M
7!+kyA\}r^
beginIndex); nd3=\.(P
} g0v},n
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privatestaticint getEveryPage(int everyPage){ XSyCT0f08
return everyPage == 0 ? 10 : everyPage; lhw]?\
} gh=s#DQsFw
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a
privatestaticint getCurrentPage(int currentPage){ 1sl^+)z8
return currentPage == 0 ? 1 : currentPage; J]UlCg
} kMWu%,s4
bj\v0NKN4
privatestaticint getBeginIndex(int everyPage, int {_0Efc=7
WMnR+?q
currentPage){ S+py\z%
return(currentPage - 1) * everyPage; ] e!CH
<N
} c9-$td&
f{xR
s-u]
privatestaticint getTotalPage(int everyPage, int EAn}8#r'(8
>y m MQEX`
totalRecords){ bN$`&fC0
int totalPage = 0; )67_yHW
`au('
xi<
if(totalRecords % everyPage == 0) z`qBs
totalPage = totalRecords / everyPage; hLPg=8nJ_
else ;
Xrx>( n
totalPage = totalRecords / everyPage + 1 ; RIOR%~U
F,Y@
return totalPage; +Mc kR
} vpcHJ^19
wUWSW<
privatestaticboolean hasPrePage(int currentPage){ u
'DM?mV:-
return currentPage == 1 ? false : true; ] as_7
} #t:]a<3Y2
`2c>M\c4U
privatestaticboolean hasNextPage(int currentPage, -CfGWO#Gbx
CB<1]Z
int totalPage){ ZKzXSI4
return currentPage == totalPage || totalPage == :*gYzk8
aehGT|
0 ? false : true; !`q*{Ojx
} EF=.L{
ZZOBMF7
v+U(
#"
} Ev* b
qIcQPJn!}
u.*@lGVW
j2# nCU54Z
|={><0
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }^Be^a<ub
Nr=ud QA{
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ;v'7l>w3\w
.CdaOWM7
做法如下: ;<`F[V
Zau
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?P@fV'Jo
ztf
VXmi'
的信息,和一个结果集List: ^ j;HYs_
java代码: XIh2Y\33ys
vn|u&}h
OLUQjvnU
/*Created on 2005-6-13*/ ,oX48Wg_+
package com.adt.bo; +]uW|owxo
x- kCNy
import java.util.List; x7K
ot]eaad
import org.flyware.util.page.Page; {[G2{ijRz
]vJZ v"ACn
/** O&l(`*P
* @author Joa *')BP;|V`
*/ p8K4^H
publicclass Result { 3#huC=zbf
0l3v>ty
private Page page; 9;2PoW8
vl*CU"4
private List content;
RR!(,j^M
eT1b88_
/** `}.K@17
* The default constructor h=SQ]nV{
*/ 1MHP#X;|
public Result(){ m6^Ua
super(); @*q WV*$h
} v'Ce|.;
*F* c
/** D5fJuT-bp
* The constructor using fields EW*!_|
* H=])o21
* @param page !R;P"%PHV
* @param content '#$Y:/
*/ C\Q3vG
public Result(Page page, List content){ jcHs!
this.page = page; <J-bDcp
this.content = content; <HM\ZDo@P
} &B^#?vmO
)#k*K9[@
/** =BQM(mal
* @return Returns the content. (A O]f fBU
*/ ,/6V ^K
publicList getContent(){ r9z_8#cR
return content; 6~zR(HzV{
} ,\!4A
7IW:,=Zk8+
/** ;'l Hw]}O*
* @return Returns the page. EJ{Z0R{{
*/ Ze~$by|9f
public Page getPage(){ B+S
&vV
return page; 5w"f.d'
} ]\5@N7h
uMa: GDh7
/** .z&V!2zp
* @param content m76**X
* The content to set. 6g4CUP'Y
*/ q9o =,[
public void setContent(List content){ { 6Lkh
this.content = content; D
7 l&L
} %y.9S=,v,
rt$zM
/** pq_DYG]
* @param page ~K% ]9
* The page to set. K:yS24\%
*/ mE)65@3%
publicvoid setPage(Page page){ %Q5D#d"p`
this.page = page; uXq?Z@af|f
} 9XWF&6w6yf
} h
Vz%{R"
#<f}.P.Uc
`q* 0^}
Yf.H$L
uW%7X2K
2. 编写业务逻辑接口,并实现它(UserManager, ^@l_K +T
3GqJs
UserManagerImpl) @+~=h{jv<
java代码: 3S1V^C-eBx
58zs%+F
~J?O ~p`&
/*Created on 2005-7-15*/ 8+Al+6d|!
package com.adt.service; #@H{Ypn`
EquNg@25W
import net.sf.hibernate.HibernateException; {%D!~,4Ht
`%AFKmc^;
import org.flyware.util.page.Page; |57KTiiNLI
t+}@J}b
import com.adt.bo.Result; UT[nzbG
@v_E'
9QG^
/** w8:F^{
* @author Joa W>
.O"Ri
*/ idnn%iO
publicinterface UserManager {
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+4\JY"oi
public Result listUser(Page page)throws *LcLYxWo
zr@Bf!VG:
HibernateException; i0/gyK
s([9/ED
} Fp4?/-]
*E:w377<}
W~p^AHco`
Tj*o [2mD
T[a1S ?_*T
java代码: fC
xN!
=YF\mhMQ:
A}C&WT~
/*Created on 2005-7-15*/
/Z! ,1
package com.adt.service.impl; rMxst
K4SR`Q
import java.util.List; nkHr(tF
7
yd"|HHx
import net.sf.hibernate.HibernateException; $m:}{:LDCf
J9ovy>G
import org.flyware.util.page.Page; S1uW`zQ!+_
import org.flyware.util.page.PageUtil; *7oPM5J|v
mkYM/*qyM&
import com.adt.bo.Result; I'"*#QOX
import com.adt.dao.UserDAO; ar+mj=m
import com.adt.exception.ObjectNotFoundException; 9bgKu6-X
import com.adt.service.UserManager; C yC<{D+
FMY
r6/I
/** .Y'kDuUu
* @author Joa B;4hI?
*/ q9pBS1Ej
publicclass UserManagerImpl implements UserManager { #[sC H
1mOZ\L!m*
private UserDAO userDAO; ']$ttfJB
nhk +9
/** NrVQK}%K
* @param userDAO The userDAO to set. dDW],d}B;
*/ 7qon:]b4
publicvoid setUserDAO(UserDAO userDAO){ U"-mLv"|
this.userDAO = userDAO;
&N0W!
} Mp75 L5
25ul,t_Du
/* (non-Javadoc) s .^9;%@$J
* @see com.adt.service.UserManager#listUser %xxe U
Bp^>R`,
(org.flyware.util.page.Page) vtR<(tOu@
*/ 5yp~PhHf
public Result listUser(Page page)throws *-Lnsi^7v
,qiS;2(
HibernateException, ObjectNotFoundException { &gF{<$$
int totalRecords = userDAO.getUserCount(); S)VuT0
if(totalRecords == 0) 5gF}7D@
throw new ObjectNotFoundException JC{}iG6r+
kSU*d/}*u
("userNotExist"); h1fJ`WT6,
page = PageUtil.createPage(page, totalRecords); r-]R4#z>
List users = userDAO.getUserByPage(page); pSQ3SM
returnnew Result(page, users); <WaiJy?
} PZLW yp
] 5P{*
} 'BAe>r_Pn
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XT>e/x9'
C'n 9n!hR
N$Gx$u3Cd
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Z>QSZ48=
A40 -])'!
询,接下来编写UserDAO的代码: PG<N\
3. UserDAO 和 UserDAOImpl: RfN5X}&A
java代码: 'ZT!a]4
d q:M!F
.%->
/*Created on 2005-7-15*/ NXeo&+F
package com.adt.dao; Uj k``;
$
}B"u;:SU
import java.util.List; UeHS4cW
lBQ|=
import org.flyware.util.page.Page; rUlpo|B
'U1r}.+b>
import net.sf.hibernate.HibernateException; "j$}'uK<
[FiXsYb.8
/** q6j]j~JxB
* @author Joa /unOZVr(
*/ Q2rZMK
publicinterface UserDAO extends BaseDAO { m
7 Fz&bN
9%zR?u
publicList getUserByName(String name)throws DVTzN(gO*~
4i~;Ql
HibernateException; qh.c#t
J\;~(:
~
publicint getUserCount()throws HibernateException; M?nnpO
.)cOu>
publicList getUserByPage(Page page)throws &`>*3m(
l*X5<b9
HibernateException; r`<evwIe
<V6#)^Or
} JH)&Ca>S
r4D66tF
_R5^4 -Qe
;F5B)&/B
,\=u(Y\I[
java代码: 1>1|>%
{'!D2y.7g
Do_L
/*Created on 2005-7-15*/ ^f`#8G7 (
package com.adt.dao.impl; Rdnd|
"9WP^[
import java.util.List; IZ2#jSDn
U_VD* F4Bv
import org.flyware.util.page.Page; ;U7\pc;S
TfZO0GL$
import net.sf.hibernate.HibernateException; n53}79Uiz
import net.sf.hibernate.Query; V 9<[v?.\
7#g C(&\A
import com.adt.dao.UserDAO; F`u{'w:Hv
yv'rJI~ Ps
/** Oi7=z?+j
* @author Joa ;<&s_C3
*/ Tu6he8Q-
public class UserDAOImpl extends BaseDAOHibernateImpl p!Gf^
} KMdfA
implements UserDAO { 6@I7UL >
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/* (non-Javadoc) kW,yZ.?f
* @see com.adt.dao.UserDAO#getUserByName T|{BT!
W1E
|f>y"T+1
(java.lang.String) 9*2hBNp+
*/ !Uj !Oy
publicList getUserByName(String name)throws ^mz_T+UOe
gj'ar
HibernateException { %^5$=w
String querySentence = "FROM user in class
(K?[gI
5cfzpOqr0
com.adt.po.User WHERE user.name=:name"; C*gSx3OG
Query query = getSession().createQuery lO9>?y8.y
Yd<~]aXM
(querySentence); 9J%>2AA
query.setParameter("name", name); uq%RZF
z(v
return query.list(); V) a6H^l
} 7=<PVJ*/
NA3yd^sr
/* (non-Javadoc) \`XJz{Lm]
* @see com.adt.dao.UserDAO#getUserCount() =riP~%_ML)
*/ aIfog+Lp
publicint getUserCount()throws HibernateException { 3oKqj>
int count = 0; lo(Ht=d
String querySentence = "SELECT count(*) FROM Fza)dJ7
@Td[rHl
user in class com.adt.po.User"; 6Nl$&jL
Query query = getSession().createQuery 92VAQU6
jkdNisq37
(querySentence); w"BTu-I
count = ((Integer)query.iterate().next h)<42Y
ebao7r5@
()).intValue(); t|y4kM
return count; wR4P0[
} 1mjv~W
9|e"n|[
/* (non-Javadoc) _*;cwMne-
* @see com.adt.dao.UserDAO#getUserByPage Zq`bd55~
I{Kc{MXn
(org.flyware.util.page.Page) z)]EB6uRg
*/ TY#1Z )%
publicList getUserByPage(Page page)throws N%_~cR;
tL).f:?
HibernateException { '|q:h
String querySentence = "FROM user in class S m1bDa\!=
yNT2kB'
com.adt.po.User"; _cJ{fYwYU
Query query = getSession().createQuery E8j9@BHU[r
i;tA<-$-
(querySentence); I;|Aiu*
query.setFirstResult(page.getBeginIndex()) AnyFg)a<
.setMaxResults(page.getEveryPage()); P! 3$RO
return query.list(); 5m bs0GL
} Ey n3Vv?v
QO?ha'Sl
} /9yiMmr5W
{&;b0'!Tf
L.Lt9W2fi
HOD2/
tFSdi.|G=
至此,一个完整的分页程序完成。前台的只需要调用 d,[KcX
9D|
FqU |
userManager.listUser(page)即可得到一个Page对象和结果集对象 R utW{wh
.kYzB.3@]
的综合体,而传入的参数page对象则可以由前台传入,如果用 0F3>kp4u
HcVPJuD
webwork,甚至可以直接在配置文件中指定。 I{AU,
"TV.$s$.
下面给出一个webwork调用示例: C>u 3n^
java代码: PRLV1o1#
ljis3{kn""
bOFLI#p&
/*Created on 2005-6-17*/ 0iE).Za0g
package com.adt.action.user; ;`+RSr^8$
sogbD9Jc
import java.util.List; 87Uv+((H
2%<jYm#'z-
import org.apache.commons.logging.Log; IMR|a*=`c
import org.apache.commons.logging.LogFactory; ~^euaOFU 6
import org.flyware.util.page.Page; CeiU2.:U
R P X`2zr
import com.adt.bo.Result; o"FX+17
import com.adt.service.UserService; xWwPrd
import com.opensymphony.xwork.Action; v-gT
3kJ
rzmk-V
/** 'H'+6
* @author Joa h@~X*yLKh
*/ iR_Syk`G*A
publicclass ListUser implementsAction{ ICTtubjV"
B5cyX*! ?
privatestaticfinal Log logger = LogFactory.getLog '; dW'Uwc
E5t+;vL~
(ListUser.class); =c.q]/M
"^=[*i
private UserService userService; 9e)+<H
d-<y'GYw
private Page page; h.9Lh ;j
oe*&w9Y}&
privateList users; uy9B8&Sr
IX*S:7S[
/* ~fF}
* (non-Javadoc) `p{!5
* vg.%. ~!9
* @see com.opensymphony.xwork.Action#execute() g
Oj5c
*/ bGi_",
8
publicString execute()throwsException{ !bcbzg2d&
Result result = userService.listUser(page); bZ9NnSuH
page = result.getPage(); F=om^6G%X5
users = result.getContent(); 5Hm!5:ZB
return SUCCESS; {^kG<v.vV
} QO7:iSZJ
by
U\I5
/** iXm||?Rnx
* @return Returns the page. ,?`1ve_K<
*/ IeB6r+4|
public Page getPage(){ NslA/"*
return page; m3(T0.j0P
} :ky<`Jfr`
9$,gTU_a
/** P\mm8s`f
* @return Returns the users. V0 F30rK
*/ zn
?;>Bl
publicList getUsers(){ ^!<7#kX
return users; 3N"&P@/0x
} N
&[,nUd
]k:m2$le
/** 8T)zB6ng
* @param page W#L"5pRg
* The page to set. euhZ4+
*/ cXY'>N
publicvoid setPage(Page page){ =[K)<5,@
this.page = page; ]pV1T
} E.`dk.
{?mQqoZ?.
/** y<1$^Y1/)
* @param users Z&w^9;30P
* The users to set. w;EXjl;X O
*/ -p.*<y
publicvoid setUsers(List users){ Jo3(bl%u
this.users = users; unnx#e]
} V*zz-
2_i
klJ[ {p
/** F!&pENQ
* @param userService 2]3HX3
* The userService to set. MgQU6O<
*/ "-n%874IT
publicvoid setUserService(UserService userService){ 3> #mO}\
this.userService = userService; 6eT'[Umx
} GWInN8.5
} |NU0tct^
qysa!B
3Y{)(%I
p RwGv
paNw5]
-
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, HS:}![P
*sB-scD
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ^dnz=FB
PGPbpl&\t
么只需要: I26gGp
java代码: %Sn 6*\z
:pDY
=/g$bZ
<?xml version="1.0"?> Ydh<T F4!
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 9V;$v
uUz`= 4%A
1.0//EN" "http://www.opensymphony.com/xwork/xwork- A3$aMCwKd
8F^,8kIR
1.0.dtd"> RF5q5<0
|R;l5ZKvV
<xwork> +F o$o
em1cc,
<package name="user" extends="webwork- !wd'::C
T1QsW<*j
interceptors"> 6
r.H8
gXu^"
<!-- The default interceptor stack name AM[jL'r|
% R|"Afa=
--> e[QxFg0E
<default-interceptor-ref vV.~76AD5
>4/L-y+
name="myDefaultWebStack"/> bqrJP3
qggk:cN1
<action name="listUser" Dk`4bYK
43>9)t
class="com.adt.action.user.ListUser"> ;}WtJ&y=M
<param |[Ie.&)
,MM>cOQ
name="page.everyPage">10</param> )@,90Vhh
<result 1/2V.:bg
#$=8g
RZj
name="success">/user/user_list.jsp</result> H=&/ Q
</action> WBr:|F+~s
4Oy.,MDQP
</package> ojx'g8yO
aZj J]~bO
</xwork> R3j#WgltP
VyWYfPK
ov`^o25f
?+n&hHRg
qByNHo7Tb
5@czK*5
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 )@]6=*%
])V2}gH
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。 $_RWd#Q(
GsIwY {d
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 DB`$Ru@
#0bO)m+NZ
d&|z=%9xl
_ktK+8*6`
Dxt),4%P
我写的一个用于分页的类,用了泛型了,hoho +Y>"/i.
N
RCBf;$O
java代码: :8^M5}
_8Nw D_"
~h)@e\Kc
package com.intokr.util; 6?V<BgCC
a)!![X?\
import java.util.List; 9-
xlvU,o
mRhd/|g*
/** ><NI'q*cQ
* 用于分页的类<br> <0u\dU
* 可以用于传递查询的结果也可以用于传送查询的参数<br> vi]r
* &8<<!#ob
* @version 0.01 0R HS]cN
* @author cheng khU6*`lQ
*/ 7/H^<%;y
public class Paginator<E> { A~Z6jK
privateint count = 0; // 总记录数 1,"I=
privateint p = 1; // 页编号 ~+O `9&
privateint num = 20; // 每页的记录数 m'cz5mcD
privateList<E> results = null; // 结果 E X%6''ys
`$s)X$W?
/** 3CR@'
qG-
* 结果总数 ;,1=zhKU.
*/ lPM3}52Xu
publicint getCount(){ D]IBB>F
return count; f64(a\Rw!^
} M1oPOC\0.
$hkq>i \
publicvoid setCount(int count){ +|y*}bG
this.count = count; |KL')&"
} Z_H?WGO
@#RuSc
/** I eG=J4:*
* 本结果所在的页码,从1开始 {<qF }i:V
* .L9']zXc`
* @return Returns the pageNo. I2f?xJ2/Z
*/ B*\$
/bk,
publicint getP(){ !FTNmyM~F
return p; 9-0<*)"b>
} ]@v}y&
:e*DTVv8
/** 8b|OXWl
* if(p<=0) p=1 u!Xb?:3uj
* T~BA)![
* @param p YT>KJ
*/ z{S:X:X
publicvoid setP(int p){ xfjd5J7'
if(p <= 0) #/Ruz'H1>
p = 1; vr=~M?
this.p = p; lDN"atSf
} A)tP()+)
w|IjQ1{
/** NXpmT4
* 每页记录数量 2{bhA5L
*/ bS.s?a
publicint getNum(){ 33Jd!orXU
return num; JVtQ,oZ
} Cyq?5\ a
&FSmqE;@^
/** "~F3*lk#E
* if(num<1) num=1 pkJ/oT
*/ 57wFf-P
publicvoid setNum(int num){ {;s;.
if(num < 1) AS)UJ/lC
num = 1; ,57$N&w
this.num = num; kb71q:[
} j^flwk
\v+u;6cx_
/** ~#R9i^Y
* 获得总页数 'JieIKu
*/ Ko6^iI1
publicint getPageNum(){ EIjI!0j
return(count - 1) / num + 1; MJ`N,E[
} $9 +YNgW>
&-%>qB|*
/** 1B|8ZmFJj
* 获得本页的开始编号,为 (p-1)*num+1 e,>%Z@92(
*/ bB!#:j>(v
publicint getStart(){ 8)N@qUV
return(p - 1) * num + 1; .N,&Uv-
} "-31'R-
UiH!Dl}<
/** cvnB!$eji
* @return Returns the results. ,R?np9wc
*/ $&{ti.l
publicList<E> getResults(){ =-NiO@5o
return results; :_5/u|{
} !gF9k8\Yr$
:4:N f
public void setResults(List<E> results){
aTd
D`h
this.results = results; qFco3
} hn.bau[
Wy4$*$
public String toString(){ t42u b
StringBuilder buff = new StringBuilder 9T7e\<8"vC
]5}=^
(); 8S]".
buff.append("{"); .f:n\eT):
buff.append("count:").append(count); w]u@G-e
buff.append(",p:").append(p); OtJ\T/q,
buff.append(",nump:").append(num); %<"}y$J
buff.append(",results:").append 6sJw@OaJ
?^i1_v7 Bi
(results); >G~mp<L
buff.append("}"); 4[yIOs
return buff.toString(); ?WUF!Jk
} +-<}+8G;
z0%\OhuCcf
} iYJZvN
1TS0X:TCn
jCioE