Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $nb[GV
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 tQVVhXQ7
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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 =pNY
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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 *~`(RV
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分页支持类: e-;}366}
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java代码: WH\d| 1)
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package com.javaeye.common.util; ?dTD\)%A
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import java.util.List; /
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publicclass PaginationSupport { ZSw.U:ep$s
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publicfinalstaticint PAGESIZE = 30; Om&Dw|xG8
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privateint pageSize = PAGESIZE; vO=fP_
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privateList items; 4-w{BZuS
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privateint totalCount; =4!mAo}
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privateint[] indexes = newint[0]; ]:;&1h3'7
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privateint startIndex = 0; 'w/hw'F6
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public PaginationSupport(List items, int al0L&z\
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totalCount){ ICCc./l|
setPageSize(PAGESIZE); M5B# TAybC
setTotalCount(totalCount); CTK;dM'uQ
setItems(items); 1YA% -~
setStartIndex(0); ;S{(]K7i
} '-6~tWC~7
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public PaginationSupport(List items, int g0H[*"hj
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totalCount, int startIndex){ Rcv9mj]l
setPageSize(PAGESIZE); <3iMRe
setTotalCount(totalCount); 0(Ij%Wi,
setItems(items); $'TM0Yu,
setStartIndex(startIndex); 49P4b<1
}
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public PaginationSupport(List items, int }G=M2V<L
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totalCount, int pageSize, int startIndex){ ^8tEach
setPageSize(pageSize); C~[,z.FvO
setTotalCount(totalCount); )"LJ
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setItems(items); SuznN
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setStartIndex(startIndex); R+| h w;
} )[ ,A_3E
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publicList getItems(){ .hiSw
return items; -di o5a
} 0c&+|>!
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publicvoid setItems(List items){ e)ZUO_Q$
this.items = items; d _
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} Q\)F;: |
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publicint getPageSize(){ _wcNgFx
return pageSize; BY*Q_Et
} E4!Fupkpf
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publicvoid setPageSize(int pageSize){ GfG|&VNlz
this.pageSize = pageSize; 'S~5"6r
} ~
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publicint getTotalCount(){ x"(KBEK~
return totalCount; JRFtsio*
} +V+a4lU14
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publicvoid setTotalCount(int totalCount){ [Q =Nn
if(totalCount > 0){ "3hMq1NQ`g
this.totalCount = totalCount; *A< 5*Db:F
int count = totalCount / ckn~#UE=
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pageSize; BHw, 4#F1;
if(totalCount % pageSize > 0) *H122njH+T
count++; F/Pep?'
indexes = newint[count]; D0Cy^_
for(int i = 0; i < count; i++){ IB<d
indexes = pageSize * t
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i;
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} p7Cs.2>M>S
}else{ ~Z+%d9ode
this.totalCount = 0; KG@8RtHsQ
} 8f7>?BUS,
} .ByuN
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publicint[] getIndexes(){ j9,P/K$:w
return indexes; K#xvu1U
} 6#yUc_5 \
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publicvoid setIndexes(int[] indexes){ AEuG v}#
this.indexes = indexes; )i<j XZ:O
} zVD:#d%b
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publicint getStartIndex(){ +{>=^9%X
return startIndex; $|@ r!/W
} fatf*}eln
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publicvoid setStartIndex(int startIndex){ 9Ee'Cm
if(totalCount <= 0) sr}E+qf
this.startIndex = 0; H1T.(M/"
elseif(startIndex >= totalCount) 6Iw\c
this.startIndex = indexes TKjFp%
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[indexes.length - 1]; qVPeB,kIz
elseif(startIndex < 0) rbQR,Nf2x
this.startIndex = 0; CNIsZv@Q
else{ h1{3njdr
this.startIndex = indexes ~v83pu1!2s
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[startIndex / pageSize]; 0Qd:`HF[
} >{Tm##@,k
} lLD12d
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publicint getNextIndex(){ Wvqhl
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int nextIndex = getStartIndex() + Hefg[$m
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pageSize; Gc!x|V;T
if(nextIndex >= totalCount) hEk$d.!}
return getStartIndex(); ZN6Z~SL_i~
else "mNq&$
return nextIndex; ^t"'rD-I
} FN;^"H
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publicint getPreviousIndex(){ ZB&6<uw
int previousIndex = getStartIndex() - MfQ!6zE
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pageSize; y==CTY@
if(previousIndex < 0) Bj~+WwD)QR
return0; 8Eq7Sa
else EzIGz[
return previousIndex; "vGW2~*)
} D-4f.Tq4#
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} nOz.G"
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抽象业务类 g*"P:n71
java代码: ]:f%l
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/** D0q":WvE
* Created on 2005-7-12 Wm3X[?V
*/ 7)k\{&+P
package com.javaeye.common.business; km40qO@3
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import java.io.Serializable; }{"fJ3] c^
import java.util.List; 4e1Y/
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import org.hibernate.Criteria; '7@R7w!E4H
import org.hibernate.HibernateException; _y3Xb`0a
import org.hibernate.Session; Lk$B{2^n
import org.hibernate.criterion.DetachedCriteria; wT\49DT"7
import org.hibernate.criterion.Projections; j+(I"h3
import _~
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org.springframework.orm.hibernate3.HibernateCallback; `p7=t)5k
import V!dtF,tH
][]
org.springframework.orm.hibernate3.support.HibernateDaoS 2|bn(QYz
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upport; g4@ lM"|S
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import com.javaeye.common.util.PaginationSupport; 42{:G8
; Hd7*`$
public abstract class AbstractManager extends 1r7y]FyH$
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HibernateDaoSupport { !YJs]_Wr
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privateboolean cacheQueries = false; e!r-+.i(
@<Yy{~L|
privateString queryCacheRegion; !L8#@BjU
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publicvoid setCacheQueries(boolean +KEWP\r
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cacheQueries){ 2[;_d;oB @
this.cacheQueries = cacheQueries; ->{KVPHe{
} +H2-ZXr
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publicvoid setQueryCacheRegion(String w'3iY,_ufC
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queryCacheRegion){ {u9}bx'<
this.queryCacheRegion = f4Rf?w*
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queryCacheRegion;
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} kM@zyDn,
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publicvoid save(finalObject entity){ S@ f9c
getHibernateTemplate().save(entity); {vO9ptR;
} Zr,VR-kW+
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publicvoid persist(finalObject entity){ 27<
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getHibernateTemplate().save(entity); Q1l '7N
} c{LO6dNg\z
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publicvoid update(finalObject entity){ Z*2Vpnqh\
getHibernateTemplate().update(entity); w8D"CwS1Rx
} -FCe:iY! A
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publicvoid delete(finalObject entity){ D#/Bx[
getHibernateTemplate().delete(entity); [ps*uva
} jMDY(mwt
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publicObject load(finalClass entity, -FlzEZ
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finalSerializable id){ 7(
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return getHibernateTemplate().load Y7[jqb1D
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(entity, id); P_#bow
} l?^4!&Nm
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publicObject get(finalClass entity, <kd1Nrr!p
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finalSerializable id){ m7>JJX3=<
return getHibernateTemplate().get [\b0Lem
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(entity, id); ~<OSYb
} L`EBfz\n
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publicList findAll(finalClass entity){ {s{j~M
return getHibernateTemplate().find("from &q|K!5[k
}XM(:|8J,
" + entity.getName()); <nK?L cP
} mcX/GO}
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publicList findByNamedQuery(finalString J{&H+rd
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namedQuery){ Oh\<VvZuN
return getHibernateTemplate A7hVHxNJ-
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().findByNamedQuery(namedQuery); ^B2
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} klR|6u]%
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publicList findByNamedQuery(finalString query, 7;(UF=4
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finalObject parameter){ JO"<{ngsQ
return getHibernateTemplate DXK}-4"\
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().findByNamedQuery(query, parameter); v+=BCyT
} 3nnJ8zQ
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ B\:%ufd
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return getHibernateTemplate f_Av3
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().findByNamedQuery(query, parameters); ["e3Ez
} 1!T1Y,w
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publicList find(finalString query){ u21EP[[,
return getHibernateTemplate().find pK'V9fD5J
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(query); 5vZ^0yFQ
} &;sP_ h
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publicList find(finalString query, finalObject gH7|=W
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parameter){ *6F[t.Or
return getHibernateTemplate().find Yv!a88+A8M
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(query, parameter); ]Y8<`;8/
} /U)D5ot<
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public PaginationSupport findPageByCriteria _ T):G6C8
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(final DetachedCriteria detachedCriteria){ i`$*Ty"x
return findPageByCriteria q Xe8Kto
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); >!1.
} RnI&8
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public PaginationSupport findPageByCriteria z(^]J`+\
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(final DetachedCriteria detachedCriteria, finalint aL&7 1^R,
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startIndex){ !XCm>]R
return findPageByCriteria Hi1JLW,
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(detachedCriteria, PaginationSupport.PAGESIZE, l
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startIndex); qC:raH_:
} pF Rg?-
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public PaginationSupport findPageByCriteria $ ,}E
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(final DetachedCriteria detachedCriteria, finalint y6,/:qm
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pageSize, TS9|a{j3!
finalint startIndex){ c%G{#}^2
return(PaginationSupport) (/j/>9iro
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getHibernateTemplate().execute(new HibernateCallback(){ j; y#[|
publicObject doInHibernate !F1N~6f
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(Session session)throws HibernateException { ;J2z p*|
Criteria criteria = 5}]"OXQ
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detachedCriteria.getExecutableCriteria(session); =~H<Z LE+
int totalCount = kep/+J-u
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((Integer) criteria.setProjection(Projections.rowCount /+;h)3PN6
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()).uniqueResult()).intValue(); uIZ -#q
criteria.setProjection o`P%&
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(null); Ksj -zR;
List items = z'\_jaj^
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criteria.setFirstResult(startIndex).setMaxResults A}N?/{y)G
SY^t} A7:/
(pageSize).list(); lXiKY@R#
PaginationSupport ps = P5nO78
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new PaginationSupport(items, totalCount, pageSize, ua]o6GlO
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startIndex); &6YIn|}
return ps; \uC15s<
} SB|Qa}62
}, true); '~&X wZ&
} DSk/q-'u
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public List findAllByCriteria(final (Dl$k Gn
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DetachedCriteria detachedCriteria){ cKim-
return(List) getHibernateTemplate K3;nY}\>
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().execute(new HibernateCallback(){ \$\ENQ;Nk
publicObject doInHibernate ^T$|J;I
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(Session session)throws HibernateException { vUU9$x
Criteria criteria = *q".-u!D[
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detachedCriteria.getExecutableCriteria(session); O6/f5
return criteria.list(); 4VCOKx
} pd7NF-KD
}, true); -
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} An"</;HU
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public int getCountByCriteria(final yXF?H"h(
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DetachedCriteria detachedCriteria){ %i-c0|,T4
Integer count = (Integer) _m'Fr
7
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getHibernateTemplate().execute(new HibernateCallback(){ MIoEauf
publicObject doInHibernate &[/w_|b
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(Session session)throws HibernateException { MLWM&cFG
Criteria criteria = muZ~*kMc
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detachedCriteria.getExecutableCriteria(session); ul2")HL];
return &twf,8
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criteria.setProjection(Projections.rowCount pxf$1
k
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()).uniqueResult(); !l 1fIc
} i Ae<&Ms
}, true); \\7ZWp\fN
return count.intValue(); NchXt6$i9
} xJZ>uTN
} <U >>ZSi
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用户在web层构造查询条件detachedCriteria,和可选的 8C~]yd
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~-m "
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PaginationSupport的实例ps。 fCtPu08{Z
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ps.getItems()得到已分页好的结果集 a@* S+3
ps.getIndexes()得到分页索引的数组 ";Rtiiu
ps.getTotalCount()得到总结果数 $8[r9L!
ps.getStartIndex()当前分页索引 !PJ 6%"
ps.getNextIndex()下一页索引 UE ,t8j
ps.getPreviousIndex()上一页索引 x{c/$+Z[
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 HnCzbt@
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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 F^LZeF[#t
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一下代码重构了。 c#]q^L\x
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我把原本我的做法也提供出来供大家讨论吧: ?Ovqp-sw
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首先,为了实现分页查询,我封装了一个Page类: 5N*Ux4M
java代码: 7=OQ8IM!
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/*Created on 2005-4-14*/ ~\3kx]^10
package org.flyware.util.page; Z(_ZAB%+D
$N=N(^
/** ;cz|ss=
* @author Joa Ox'/`Mppw
* >P $;79<
*/ /<8N\_wh
publicclass Page { OdY=z!Fls
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/** imply if the page has previous page */ adi[-L#
privateboolean hasPrePage; pBP.x#|
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/** imply if the page has next page */ ]t*[%4
privateboolean hasNextPage; XNb ZNaAd
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/** the number of every page */ S&Ee,((E(
privateint everyPage; ]B]*/
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/** the total page number */ m7GR[MR
privateint totalPage; zf>5,k'x'A
{;
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/** the number of current page */ P7f,OY<@%o
privateint currentPage; f5==";eP
?k|H3;\
/** the begin index of the records by the current =.`qixN
%-AE]-/HI
query */ t"YNgC ^
privateint beginIndex; k` (jkbEZ
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/** The default constructor */ ?
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public Page(){ ~w;]c_{.b
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} ~E^,=4
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/** construct the page by everyPage G>+1*\c
* @param everyPage NAzX". g
* */ k') E/n
public Page(int everyPage){ FG!X"<he
this.everyPage = everyPage; fQ=MJ7l
} KyO8A2'U
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/** The whole constructor */ z5X~3s\dP
public Page(boolean hasPrePage, boolean hasNextPage, z]bwnJfd
{gaai
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int everyPage, int totalPage, tDCw-
int currentPage, int beginIndex){ `[YngYw
this.hasPrePage = hasPrePage; }O4se"xK
this.hasNextPage = hasNextPage; Ep4Hqx $
this.everyPage = everyPage; FHPXu59u
this.totalPage = totalPage; eVcANP
this.currentPage = currentPage; AisN@
this.beginIndex = beginIndex; [J0v&{)?
} N8`4veVBx'
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/** P0-Fc@&Y
* @return x/:4{
* Returns the beginIndex. :ECi+DxBK
*/ %,*G[#*&
publicint getBeginIndex(){ G^1b>K
return beginIndex; "uPy,<l
}
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,[nm_^R*\
/** <d7V<&@o=
* @param beginIndex *AIEl"29
* The beginIndex to set. !"TZ:"VZU
*/ -gz0md|Y
publicvoid setBeginIndex(int beginIndex){ KZBrE$@%5
this.beginIndex = beginIndex; do
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} :` $@}GI
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/** 3?s ?XAh
* @return "XLe3n
* Returns the currentPage. ]fI/(e_U
*/ 4E:bp
publicint getCurrentPage(){ W];EKj,3W
return currentPage; &wetzC)
} BD#.-xWV
:Ld!mRZF
/** 2~;&g?T6
* @param currentPage 0%;146.p
* The currentPage to set. bxXiQa
*/ U~2`P
publicvoid setCurrentPage(int currentPage){ oT|m1aGE
this.currentPage = currentPage; ,`8Y8
} '7im
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/** ;#G%U!p
* @return Y+/lX 6'
* Returns the everyPage. G;oFTP>o
*/ ]PNowS\
publicint getEveryPage(){ qsg>5E
return everyPage; !)Rr]
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} |H ;+1
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/** lg1PE7
* @param everyPage Jll-X\O`-
* The everyPage to set. O hR1Jaed
*/ G(1 K9{i$
publicvoid setEveryPage(int everyPage){ u>Ki$xP1
this.everyPage = everyPage; ZZ)G5ji
} 9|S` ub'
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/** 2#_38=K=@
* @return 5`E))?*"Pe
* Returns the hasNextPage. \T-~JQVj
*/ `HX3|w6W;
publicboolean getHasNextPage(){ 1ZKzumF
return hasNextPage; H "+c)FGi
} chAan~r[*
(=T$_-Dj`}
/** i!MwBYk
* @param hasNextPage c/u_KJFF-n
* The hasNextPage to set. Eb.;^=x
*/ Dr"/3xm
publicvoid setHasNextPage(boolean hasNextPage){ mPVE?jnR^0
this.hasNextPage = hasNextPage; wy4q[$.4v
} zb2K;%Qs+f
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/** a`Z{
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* @return Z-|li}lDr
* Returns the hasPrePage. iG[?
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*/ Ds5NAp:x
publicboolean getHasPrePage(){ F$hZRZ
return hasPrePage; Ud3""C5B
} N5q725zJ
ZcZ;$*
/** j.QHkI1.
* @param hasPrePage z*.v_Mx
* The hasPrePage to set. "jZm0U$,*
*/ &P n]
publicvoid setHasPrePage(boolean hasPrePage){ Z|`fHO3j
this.hasPrePage = hasPrePage; =%h~/,
} nN ~GP"}
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/** }#aKFcvg
* @return Returns the totalPage. Ob(leL>ow
* %N~;{!![p
*/ "oE* 9J?e
publicint getTotalPage(){ K~>jApZ%
return totalPage; /=
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} 9!t4>
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9
/** R[yL_>
* @param totalPage /{G/|a
* The totalPage to set. jpO38H0)
*/ #O</\|aH)i
publicvoid setTotalPage(int totalPage){ 5V|tXsy:
this.totalPage = totalPage; &`PbO
} Jf+7"![|
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} [~?M/QI9
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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 h[l{ 5Z*
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个PageUtil,负责对Page对象进行构造: ALR:MAXwC
java代码: .! j#3J..u
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/*Created on 2005-4-14*/ B,0+HoP
package org.flyware.util.page; .cw=*<zeg
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import org.apache.commons.logging.Log; fm6]CU1^
import org.apache.commons.logging.LogFactory; l\U*sro<
;qT5faKB3J
/**
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* @author Joa hgj0tIi/
* T{~M iC6A
*/ <`mOU}0)
publicclass PageUtil { 7z>+w
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privatestaticfinal Log logger = LogFactory.getLog 4JK@<GBK6
2))t*9;h
(PageUtil.class); KW:r;BFx
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/** x9\J1\
* Use the origin page to create a new page <tQXK;
* @param page Wy,"cT
* @param totalRecords w#d} TY
* @return 0hZxN2r
*/ >%i9 oI<)
publicstatic Page createPage(Page page, int T Xl\hL\+
L)G">T;
totalRecords){ r
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return createPage(page.getEveryPage(), [+7"{UvT
Fi k@hu
page.getCurrentPage(), totalRecords); Q^ q=!/qQ
} j%GbgJ
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/** H>Sf[8w)%
* the basic page utils not including exception 6DO0zNTY
Z#LUez;&t#
handler I`#EhH
* @param everyPage KY8^BjY@
* @param currentPage Lo5Jb6nm
* @param totalRecords SZI7M"gf/+
* @return page %8g$T6E[<2
*/ 0c-QIr}m
publicstatic Page createPage(int everyPage, int C*]AL/
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currentPage, int totalRecords){ eFes+i( 35
everyPage = getEveryPage(everyPage); 5GUH;o1m
currentPage = getCurrentPage(currentPage); wz)m{:b<
int beginIndex = getBeginIndex(everyPage, x:vrK#8D>
n=r=u'oi
currentPage); 0 c,bet{m
int totalPage = getTotalPage(everyPage, dgm+U%E
&F86SrsI
totalRecords); *+&z|Pwv[^
boolean hasNextPage = hasNextPage(currentPage, hxP6C6S
w4`!Te
totalPage); AtuZF
boolean hasPrePage = hasPrePage(currentPage); wbl${@4
8\P
JSr
returnnew Page(hasPrePage, hasNextPage, 8QPT\~
everyPage, totalPage, U=M#41J
currentPage, 2kC^7ZAwu
[gTQ-
beginIndex); }3Df]
} jf2y0W>6s
8R
BDJ
privatestaticint getEveryPage(int everyPage){ enWF7`
return everyPage == 0 ? 10 : everyPage; ?TRW"%
} }t}38%1i
M2a}x+5'
privatestaticint getCurrentPage(int currentPage){ dzpj9[
return currentPage == 0 ? 1 : currentPage; IOn`cbV:
} _J+]SNk
kA1f[AL
privatestaticint getBeginIndex(int everyPage, int ,7QBJ_-;QJ
3s#|Y,{?6R
currentPage){ !Q[;5Lqt
return(currentPage - 1) * everyPage; W&WB@)ie
} KPD@b=F
1g+LF[*-~
privatestaticint getTotalPage(int everyPage, int %+/f'6kR
sn2r>m3
totalRecords){ yo'q[YtP'
int totalPage = 0; gt#MeU
Cq
TH!'N
if(totalRecords % everyPage == 0) ]w5ji
totalPage = totalRecords / everyPage; cF-Jc}h
else 30t:O&2<
totalPage = totalRecords / everyPage + 1 ; Qu!OV]Cc
;>cLbjD
return totalPage; ojiM2QT}m
} YNuewD
1VRqz5
privatestaticboolean hasPrePage(int currentPage){ [B.W1 GL!
return currentPage == 1 ? false : true; pq%t@j(X
} y-D>xV)n
L;
@aE[#z
privatestaticboolean hasNextPage(int currentPage, _a?wf!4>P
Q1]V|S;)X
int totalPage){ Oz_b3r
return currentPage == totalPage || totalPage == B/kcb(5v
&3!i@2d;3f
0 ? false : true; "4J?JR
} wOD/Z8
X%RQB$
PEMxoe<+
} |p'_k(z}
lqhHbB
/<(R
k9.u[y.
6nM
rO$i0k
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。 *g}vT8w'}
d@_'P`%-
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 $IZ*|>(
s0x@
u
做法如下: kfH9Y%bOy
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !NlB%cF
]W89.><%14
的信息,和一个结果集List: n=lggBRx
java代码: c80"8r
DN2hv2
KFCQYdI`d
/*Created on 2005-6-13*/ wWp?HDl"M
package com.adt.bo; RlG'|xaT
|:`?A3^m#
import java.util.List; C.DoXE7
]9!Gg
import org.flyware.util.page.Page; G <} 7vF
XRX7qo(0g
/** /v<e$0~s<
* @author Joa ~:'gvR;x
*/ J
tn&o"C
publicclass Result { o(S^1j5
B8P@D"u
private Page page; Dg ?Ho2ih
@U7U?.p
private List content; :Kt{t46)
*J*zml3
/** ;h*"E(Pp
* The default constructor )o}=z\M-bN
*/ |\yDgs%EGy
public Result(){ gwkZk-f\p
super(); X"]mR7k
} '6Rs0__
z.Ve#~\
/** o
=jX
* The constructor using fields lcuH]z
* z^SN#v$
* @param page Au\=ypK
* @param content {d{WMq$
*/ kC,DW%Ls
public Result(Page page, List content){ 'PxL^
this.page = page; Bk@_]a
this.content = content; SO8|]Fk
} 1bFEx_
Hf`&&
/** l.Lc]ZpB
* @return Returns the content. {#d`&]
*/ Jf8'N
ot
publicList getContent(){ ]2u7?l
return content; '<U[;H9\
} $$)<(MP3
.WPuQZ!
/** )Uoe~\
* @return Returns the page. /Wta$!X{-
*/ yD=)&->Ra
public Page getPage(){ )G F
return page; ~T{d9yNW1
} UVvt&=+4
'ra_Zg[j
/** rUJSzLy
* @param content <jg
wdbT"6
* The content to set. jAK`96+D~b
*/ \)s 3]/"7
public void setContent(List content){ r]K0
]h@B
this.content = content; 0v,`P4_k
} YH:W]
r>D[5B
/** ]mDsUZf<
* @param page #|2g{7g*
* The page to set. o2t@-dNi
*/ 4$#ia
F
publicvoid setPage(Page page){ O,z%7><
this.page = page; 1tK6lrhj
} =V4_DJ(&
} vzT6G/
c_j)8
9/^Bj
[Nzg
8FP
K<fq=:I3
2. 编写业务逻辑接口,并实现它(UserManager, w2mlqy2L
1QdB`8in
UserManagerImpl) .bl/At3A
java代码: Wg3WE1V
-$Z-hxs^
f+(w(~O
/*Created on 2005-7-15*/ R,k[Kh
package com.adt.service; ~S<F
[&k& $04_
import net.sf.hibernate.HibernateException; .LVOaxT
-2mOgv
import org.flyware.util.page.Page; F$pd]F!#
& m ";D
import com.adt.bo.Result; iH -x
Q(eQZx{
/** 5;uX"zG
* @author Joa nD{;4$xP`
*/ ) a2m<"
publicinterface UserManager { GA*Khqdid
`J;/=tf09
public Result listUser(Page page)throws Zm'::+tl
wBaFC\CW
HibernateException; d3q/mg 5a
4pHPf<6
} k?*DBXJv
=u1w\>( 2Y
,)\5O0 D6
1x5CsmS
x'PjP1
java代码: 'jO-e^qT
u\\niCNA
)^a#Xn3z
/*Created on 2005-7-15*/ [/`Hz]R
package com.adt.service.impl; GA@Q:n8UuR
70l;**"4
import java.util.List; "r(pK@h
Vste$V
import net.sf.hibernate.HibernateException; 7]+'%Uwu)
o\Vt $
import org.flyware.util.page.Page; oXOO 10
import org.flyware.util.page.PageUtil; 4OgGZ
in|7ucSlg
import com.adt.bo.Result; fP4IOlHkE
import com.adt.dao.UserDAO; a5g{.:NfO
import com.adt.exception.ObjectNotFoundException; RwLdV+2\R`
import com.adt.service.UserManager; ^oZs&+z
L,ey3i7a\
/** ?;kc%Rz
* @author Joa =kkA
*/ 0BZOr-i
publicclass UserManagerImpl implements UserManager { #~qp8
w
D&lXi~Z%.
private UserDAO userDAO; -D':7!@
9fLP&v
/** KQI} 5
* @param userDAO The userDAO to set. z Clm'X/
*/ OX`GN#yl
publicvoid setUserDAO(UserDAO userDAO){ * =N6_
this.userDAO = userDAO; Y:Tt$EQ
} :jp$X|
`v+O5
/* (non-Javadoc) {Q3#]Vu
* @see com.adt.service.UserManager#listUser 5m;wMW<
zEL[%(fnc
(org.flyware.util.page.Page) ?At-
*/ m<HjL
public Result listUser(Page page)throws L&k$4,Z9
%Q4w9d
HibernateException, ObjectNotFoundException { WmBnc#>gK
int totalRecords = userDAO.getUserCount();
x a,LV
if(totalRecords == 0) ?B4QTx9B
throw new ObjectNotFoundException /9^0YC;Y*
N.cRZm%
("userNotExist"); w3hL.Z,kV
page = PageUtil.createPage(page, totalRecords); G+yz8@
List users = userDAO.getUserByPage(page); ~_\2\6%1^n
returnnew Result(page, users); @Bwl)G!|
} \)
ONy9
?UZyu4O%
} GM92yi!8
#SUq.A
`I:,[3_/
Ceb i9R[
n8ya$bc
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 h$h`XBVZe;
/]>{"sS(
询,接下来编写UserDAO的代码: I>zn$d*0
3. UserDAO 和 UserDAOImpl: h^X.e[
java代码: 25KZe s)
U?C{.@#w
O/"&?)[v
/*Created on 2005-7-15*/ Zdz GJ[$
package com.adt.dao; 4vJIO{m
+Uk.|@b=-V
import java.util.List; LKG|S<s
tH!z7VZ
import org.flyware.util.page.Page; RH 0a\RC!G
+N!{(R:"v}
import net.sf.hibernate.HibernateException; he6)
L6T
Ct33S+y
/** '0?E|B]Cp%
* @author Joa aB_z4dqwU
*/ O&%T_Zk@@
publicinterface UserDAO extends BaseDAO { ps
J 1J
j>M%?Tw
publicList getUserByName(String name)throws XV!EjD~q
j<5R$^?U
HibernateException; sZ$ ~abX
8=Ht+Br
publicint getUserCount()throws HibernateException; /!3:K<6@
L4-Pq\2
publicList getUserByPage(Page page)throws 7dW&|U
<6 $%Y2
HibernateException; ]<_+uciP5[
#bH[UId[
} a}{! %5
pr?(5{BL
7 {<lH%Tn
]d(}b>gR~(
4 ETVyK|
java代码: Kj5f:{Ur
*a@UV%u
|U0@(H
/*Created on 2005-7-15*/ 4\RuJx
package com.adt.dao.impl; )QT+;P.
ddxv.kIj.
import java.util.List; EpMEA1=&
6.=b^6MV
import org.flyware.util.page.Page; exvsf|
zt6ep=
import net.sf.hibernate.HibernateException; K.I r+SB
import net.sf.hibernate.Query; 548BM^^"r
_FgeE`X
import com.adt.dao.UserDAO; djM=QafB:C
p:))ne:7
/** |+''d
* @author Joa HB:i0m2fJW
*/ 0:p#%Nvg
public class UserDAOImpl extends BaseDAOHibernateImpl n!nv.-n
tDVdl^#
implements UserDAO { 6Rj
X
RPQ)0.O7
/* (non-Javadoc) rY.:}D
* @see com.adt.dao.UserDAO#getUserByName c i>=45@J
zq&lxySa
(java.lang.String) '@P[fSQ
*/ Ckp=d
publicList getUserByName(String name)throws Qa+gtGtJ
UQ?8dw:E~
HibernateException { T~E83Jw
String querySentence = "FROM user in class `}l%Am
7\lb+^$
com.adt.po.User WHERE user.name=:name"; HVpaVM
Query query = getSession().createQuery 6h%(0=^
95/C4q
(querySentence); Yn/-m
Z
query.setParameter("name", name); DEhA8.v
return query.list(); CXA8V"@&b/
} I 3PnyNZ
PHkvt!uH
/* (non-Javadoc) Cz%ih#^b
* @see com.adt.dao.UserDAO#getUserCount() 71InYIed
*/ $G[##j2
publicint getUserCount()throws HibernateException { he #iWD'
int count = 0; JZ
[&:
String querySentence = "SELECT count(*) FROM E%N]t} }[
98"N UT
user in class com.adt.po.User"; `1gsrHi4N
Query query = getSession().createQuery 4j5 "{
WP9=@X Z
(querySentence); :C5N(x
count = ((Integer)query.iterate().next o-_a0j
-u{:39y{n
()).intValue(); Z)~2{)
return count; Z "u/8
} $9/r*@bu8d
TEtZPGFl
/* (non-Javadoc) B=7L+6
* @see com.adt.dao.UserDAO#getUserByPage q!4dK4`#5
=*I9qjla[?
(org.flyware.util.page.Page) E;N8{Ye_
*/ <jF <_j
publicList getUserByPage(Page page)throws n>'}tT)U
;N|6C+y
HibernateException { \=JKeL|6[S
String querySentence = "FROM user in class J$oJ
aryr
com.adt.po.User"; ak zb<aT
Query query = getSession().createQuery ~JJv 2
*zcH3a,9"x
(querySentence); X9J^Olq
query.setFirstResult(page.getBeginIndex()) 9TLP(
.setMaxResults(page.getEveryPage()); ;_!;D#:
return query.list(); $si2H8
} ?(z3/"g]
_kSus
} lz>hP
e j~ /sO
827N?pU$)
o,L !F`W
WW.=>]7;
至此,一个完整的分页程序完成。前台的只需要调用 6 S8#[b
[(hENX}o:
userManager.listUser(page)即可得到一个Page对象和结果集对象 4Hw8w7us:
(`&g
的综合体,而传入的参数page对象则可以由前台传入,如果用 #X+)
YL]x>7T~4t
webwork,甚至可以直接在配置文件中指定。 /D12N'VaE
VCI G+Gz
下面给出一个webwork调用示例: DIY WFVh
java代码: s$Mj4_p3l
?^5x
d1>E
;rX4${h
/*Created on 2005-6-17*/ X!m/I
i$q
package com.adt.action.user; ty ~U~
UU_k"D~
import java.util.List; \*7Tj-#
F n\)*; ^
import org.apache.commons.logging.Log; e>[QF+e)y
import org.apache.commons.logging.LogFactory; F
1BPzRo`
import org.flyware.util.page.Page; ^J327
wS4zAu
import com.adt.bo.Result; F=cO=5Iz
import com.adt.service.UserService; I<$lpU_H
import com.opensymphony.xwork.Action; B}vI<?c
*N 't ;
/** 5%9&
7
* @author Joa {x+jFj.
*/ %!@Dop/<
publicclass ListUser implementsAction{ 1.+MX(w
qhogcAvE
privatestaticfinal Log logger = LogFactory.getLog E7N1B*KI
SpkD
(ListUser.class); 9%x[z%06
-C\m'T,1
private UserService userService; Fw|5A"9'a'
iS"rMgq
private Page page; `Tab'7
[p(Y|~
privateList users; TR#5V@e.m
KjLj
/* +m"iJW0
* (non-Javadoc) %9IM|\ulp
*
@>BFhH
* @see com.opensymphony.xwork.Action#execute() ^T^fowt=r
*/ E|No$QO)
publicString execute()throwsException{ I)6)~[:'
Result result = userService.listUser(page); B!,})F$x
page = result.getPage(); T^"d%au
users = result.getContent(); ruoiG?:T
return SUCCESS; "B.l j)
} b*$^8%
}hGbF"clqg
/** ~q<UE\H
* @return Returns the page. [Ga9^e$Zv
*/ _9<Ko.GVq
public Page getPage(){ jv W/M.q4
return page; Od!j+.OY<
} fPst<)
xD1w#FMlQs
/** na <g
/&
* @return Returns the users. 8G9V8hS1#B
*/ srUpG&Bcx
publicList getUsers(){ K{N#^L!
return users; mI}'8.
} /<GygRs
qUCiB}
/** @n<WM@|l
* @param page B;^7Yu0,
* The page to set. (d_{+O"
*/ 07CGHAxJ`
publicvoid setPage(Page page){ U:ZklDW
this.page = page; ++xEMP)
} KVJiCdg-
9^`G `D
/**
[~ fJ/
* @param users vQztD_bX%
* The users to set. HZR~r:_
i
*/ NX$$4<A1
publicvoid setUsers(List users){ \s[Uq
this.users = users; -8g ;t3z
} "Y4tt0I
*2@Ne[dYEF
/** <UeO+M(
* @param userService 7)~/`w)P
* The userService to set. /z6NJ2jb
*/ ]e
R1
+Nl
publicvoid setUserService(UserService userService){ Aj-}G^>#
this.userService = userService; Dg\fjuK9
} $$AKz\
} WnA]gyc
`XQM)A
74QWGw`,
]ZZ7j
wOINcEdx
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, .BZw7
YV
(1*?2u*j
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 v@[MX- ,8
TR|G4l?
么只需要: %
`\8z
java代码: J7$5<
Ry tQNwv3
Es1Yx\/:
<?xml version="1.0"?> }wz )"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork zS]Yd9;X1
B$aboL2
1.0//EN" "http://www.opensymphony.com/xwork/xwork-
!1;DRF
UEt#;e
1.0.dtd"> u
JGYXlLE
}Z"<KF
<xwork> ^2XoYgv
&H<-joZ)Z\
<package name="user" extends="webwork- ewD61Y8-
!ZHPR:k|
interceptors"> FX 0^I 0
n~k;9`
<!-- The default interceptor stack name (yn!~El3
L3'o2@$
--> IKH#[jW'IB
<default-interceptor-ref 5Tkh6 s
=]E;wWC
name="myDefaultWebStack"/> qVx0VR1:
8g^OXZ
<action name="listUser" qbpvTTF
ZI-)'
class="com.adt.action.user.ListUser"> USfOc
<param Z'hW;^e%_z
BB>3Kj:|
name="page.everyPage">10</param> e=QnGT*b5
<result K'7i$bl%
{C[<7ruF
name="success">/user/user_list.jsp</result> mS6L6)] S
</action> Fn yA;,*
#P<v[O/rA
</package> JEGcZeq)
Wl?*AlFlk
</xwork> AS'a'x>8>,
79z(n[^
Xq1n1_Z
52,p CyU
wqK>=Ri_
[-=PK\ B
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 `fj(xrI
iO(9#rV
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Atzp\oO
JIQS'r
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 FD,M.kbg
/k l0(='
\M'b%
\|L@
\ 2*<Pq
我写的一个用于分页的类,用了泛型了,hoho VrrCW/o
!i2=zlpb[
java代码:
3_+-t5
K3M<%
0,{Dw9W:
package com.intokr.util; j"7 z
L Lm{:T7
import java.util.List; ]+{Cy\*kR
FU E/uh
/** OXK?R\ E+
* 用于分页的类<br> ubju uha"
* 可以用于传递查询的结果也可以用于传送查询的参数<br> H*?U@>UU
* ?TLMoqmXM{
* @version 0.01 dyC: Mko=
* @author cheng EL;Ir tU
*/ w$u=_
public class Paginator<E> { dc|"34;^"
privateint count = 0; // 总记录数 T4F}MVK
privateint p = 1; // 页编号 k^:$ETW2
D
privateint num = 20; // 每页的记录数 j]6Z*AxQ
privateList<E> results = null; // 结果 jxm.x[1ki^
(>%Ddj6_>
/** pJ ;J>7Gt
* 结果总数 5rr7lwWZ
*/ != _:*U)-'
publicint getCount(){ x}?y@.sn8
return count; m>yk4@a
} y4t M0h
G!C2[:[g
publicvoid setCount(int count){ f
nX!wN
this.count = count; b54<1\&
} ?kI-o0@O.
) ^'Q@W
/** *!ZU"q}i
* 本结果所在的页码,从1开始 k3da*vwE
* \SHYwD}*Pr
* @return Returns the pageNo. A|,\}9)4X[
*/ ce0TQ
publicint getP(){ nw+L _b
return p; $6Lgaz
} &.y:QVR,!
BuCU_/H
/** MMqkNe
* if(p<=0) p=1 ZT5t~5W
* V7G?i\>
* @param p :z_D?UQ
*/ EW%%W6O6
publicvoid setP(int p){ s/Fc7V!;
if(p <= 0) Z,M?!vK
p = 1; ;cH|9m:Y
this.p = p; W/<]mm~95
} ,B(UkPGT
16 _HO%v->
/** v`A^6)U#M
* 每页记录数量 o7i/~JkTP
*/ *6sB$E_y
publicint getNum(){ "
;_bB"q*
return num; !@{_Qt1
} ^>gRK*,
s3HwBA
/** ^3B{|cqf
* if(num<1) num=1 &PI}o
*/ (cAv :EKpo
publicvoid setNum(int num){ +Pd&YfU9
if(num < 1) _A|1_^[G(
num = 1; z6#N f,
this.num = num; eS8tsI
} ,> A9OTSN\
TviC1 {2
/** ]:(>r&'
* 获得总页数 :WIbjI=
*/ !MSz%QcO
publicint getPageNum(){ =unMgX]$
return(count - 1) / num + 1; M7-piRnd4
} <"{Lv)4
aR6?+`6<
/** )HNbWGu
* 获得本页的开始编号,为 (p-1)*num+1 BQ{Gp 2N
*/ S}gUz9ks
publicint getStart(){ mf=, 6fx28
return(p - 1) * num + 1; m3C&QdjRp
} JryDbGc8
k!H;(B"s-
/** /6B!&b2f
* @return Returns the results. fQi7e5
*/ $IX>o&S@|
publicList<E> getResults(){ QDYS}{A:V
return results; WCA`34(
} /Mb?dVwA
`e .;P
public void setResults(List<E> results){ ^)<>5.%1''
this.results = results; &&4av*\I
} zYO+;;*@
Ap9CQ h=!
public String toString(){ B;XFPQ#b
StringBuilder buff = new StringBuilder x.qn$?3V]
?`V%[~4_I
(); XL c&7
buff.append("{"); M >P-0IC
buff.append("count:").append(count); ;ZPAnd:pb
buff.append(",p:").append(p); .%_scNP
buff.append(",nump:").append(num); $%ZEP>]
buff.append(",results:").append q4@n
pbx
kU$P?RD
(results); {\[u2{
buff.append("}"); b2u_1P\
return buff.toString(); "(5A5>
} FKY|xG9
Yxz(g]
} (2(I|O#
zk=5uKcPE
9#{?*c6