Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :)#;0o5
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #,tT`{u1q
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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 )R7Sh51P
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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 ~
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分页支持类: /x49!8
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java代码: T >8P1p@A,
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package com.javaeye.common.util; kGD_w
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import java.util.List; P3"R2-
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publicclass PaginationSupport { M|blg!j;
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publicfinalstaticint PAGESIZE = 30; m]jA(
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privateint pageSize = PAGESIZE; YF{MXK}
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privateList items; D_lRYLA+
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privateint totalCount; z 3aGK
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privateint[] indexes = newint[0]; 1h@qcom9K_
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privateint startIndex = 0; 6!_Wo\_%
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public PaginationSupport(List items, int Y|R=^
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totalCount){ SRfh{u
setPageSize(PAGESIZE); 5az%yS
setTotalCount(totalCount); kQ>2W5o-d-
setItems(items); ^t'mW;C$4
setStartIndex(0); hwGK),?"+
} Ovt]3`U9J
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public PaginationSupport(List items, int e_b,{l#
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totalCount, int startIndex){ 1>e30Ri,g
setPageSize(PAGESIZE); ;
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setTotalCount(totalCount); c~U0&V_`j
setItems(items); #czInXTTx
setStartIndex(startIndex); 44e]sT.B
} |*?N#0s5h
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public PaginationSupport(List items, int \~#\ [r_
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totalCount, int pageSize, int startIndex){ IBNg2Y
setPageSize(pageSize); ^\v]Ltd
setTotalCount(totalCount); 8sj2@d
setItems(items); z<eu=OD4t
setStartIndex(startIndex); +c_AAMe
} QjLU@?&
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publicList getItems(){ 3}}/,pGSc
return items; _-f LD
} b=Nsz$[
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publicvoid setItems(List items){ %ZoJu
this.items = items; lH3.q4D
5
} mH,s!6j?Vp
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publicint getPageSize(){ .45wwouZkc
return pageSize; !po,Z&
} L@\t]
~
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publicvoid setPageSize(int pageSize){ D&m1yl@\J
this.pageSize = pageSize; XF: wsC
} 6Y [&1c8
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publicint getTotalCount(){ Fe[6Y<x+:
return totalCount; r5&c!b \
} W4 q9pHQ
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publicvoid setTotalCount(int totalCount){ w8D8\`i!"
if(totalCount > 0){ @16y%]Q-E#
this.totalCount = totalCount; 0iSNom}m
int count = totalCount / }|h-=T '
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pageSize; Yy
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if(totalCount % pageSize > 0) (NUXK
count++; `T[yyOL/
indexes = newint[count]; +PYR
for(int i = 0; i < count; i++){ l&Q@+xb>
indexes = pageSize * "Io-%Su+
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i; w+rw<,u%
} kk126?V]_
}else{ Jur$O,u40l
this.totalCount = 0; h1>.w
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} 3>(~5
} a:|]F|
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publicint[] getIndexes(){ yq3"VFh3d
return indexes; y3*IF2G
} mp3 Dc
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publicvoid setIndexes(int[] indexes){ 'PMzm/;8st
this.indexes = indexes; EHe-wC
} m$Tt y[0
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publicint getStartIndex(){ Ahd{f!
return startIndex; Kc9)Lzu+
} tSDp>0yZ3
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publicvoid setStartIndex(int startIndex){ =L$RY2S"
if(totalCount <= 0) AF{o=@
this.startIndex = 0; ^1}ffE(3>
elseif(startIndex >= totalCount) *|+ ~V/#
this.startIndex = indexes VAxk?P0j6
fZd~},X
[indexes.length - 1]; iEFS>kL8e
elseif(startIndex < 0) lSId<v?C>
this.startIndex = 0; u*;53 43
else{ B7ys`eiB5C
this.startIndex = indexes RDG,f/L2
BJ/#V)
[startIndex / pageSize]; \No22Je6d
} ;+qPV7Z
} Q!%CU8!`&
7L:R&W6
publicint getNextIndex(){ zGFW?|o<
int nextIndex = getStartIndex() + S4~;bsSx
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pageSize; Z42v@?R.!W
if(nextIndex >= totalCount) J2#=`|t"
return getStartIndex(); fs]Zw mA^
else ]O&A:Us
return nextIndex;
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} s?K4::@Fv
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publicint getPreviousIndex(){ f{Y|FjPp=E
int previousIndex = getStartIndex() - 8CSvg{B
>|I3h5\M
pageSize; { K0T%.G
if(previousIndex < 0) zZh`go02E
return0; ZCJ8I
else Xhkw<XbV
return previousIndex; ;1OTK6
} ?y45#Tk]
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} S(-=I!.G{
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抽象业务类 qP<,"9!I
java代码: .y2<2eW
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/** `y6l^ep
* Created on 2005-7-12 D3lYy>~d5;
*/ 246lFxG.
package com.javaeye.common.business; &%r#eB?7
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import java.io.Serializable; @Q1jH~t
import java.util.List; 1W!n"3#
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import org.hibernate.Criteria; A>g$[
import org.hibernate.HibernateException; n*6s]iG
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import org.hibernate.Session; y?@Y\ b
import org.hibernate.criterion.DetachedCriteria; x[^A9
import org.hibernate.criterion.Projections; A7RX2
import /[IQ:':^
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org.springframework.orm.hibernate3.HibernateCallback; lqCn5|S]
import v(7A=/W_
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org.springframework.orm.hibernate3.support.HibernateDaoS Q%xY/xH]
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upport; 7h0'R k
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import com.javaeye.common.util.PaginationSupport; 2,;t%GB
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public abstract class AbstractManager extends r"[T9
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HibernateDaoSupport { 9|WWA%p
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privateboolean cacheQueries = false; oX4uRc7wR
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privateString queryCacheRegion; (*x"6)`
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publicvoid setCacheQueries(boolean KRZV9AJ
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cacheQueries){ NGY I%:
this.cacheQueries = cacheQueries; ,s76]$%4
} )\;r
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w$ {
publicvoid setQueryCacheRegion(String "y0A<-~
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queryCacheRegion){ dSZ#,Ea"
this.queryCacheRegion = urB3
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queryCacheRegion; *$$V,6O.
} OJ 5 !+#>
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publicvoid save(finalObject entity){ i|^6s87"N2
getHibernateTemplate().save(entity); ] O>7x
} g:M7/- "
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publicvoid persist(finalObject entity){ UYOn
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getHibernateTemplate().save(entity); 2oG|l!C
} y}HC\A77uD
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publicvoid update(finalObject entity){ =3C)sz}
getHibernateTemplate().update(entity); eBIR*TZ):
} K>6k@okO
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publicvoid delete(finalObject entity){ yWtr,
getHibernateTemplate().delete(entity); Fd&!-`T?
} E0]h|/A]
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publicObject load(finalClass entity, ^(*O$N*#
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finalSerializable id){ D#1~]d
return getHibernateTemplate().load X$iJ|=vW
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(entity, id); D])YP0|}
} TF-Ty
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publicObject get(finalClass entity, "nno)~)u
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finalSerializable id){ =L),V~b
return getHibernateTemplate().get *;E+9^:V
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(entity, id); zf>^2t*\
} M2Fj)w2
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publicList findAll(finalClass entity){ $YY)g$
return getHibernateTemplate().find("from _JTxm>
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" + entity.getName()); Wo+CQH6(
} )z235}P
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publicList findByNamedQuery(finalString Ij}F<ZgZG
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namedQuery){ *8.@aX3
return getHibernateTemplate 'Rd*X6dv
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().findByNamedQuery(namedQuery); #lsh N,CPm
} Wo9psv7.
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publicList findByNamedQuery(finalString query, L@n6N|[_
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finalObject parameter){ EH*ym#Y
return getHibernateTemplate +i@yZfT
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().findByNamedQuery(query, parameter); 4!~
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} hdr}!wV
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publicList findByNamedQuery(finalString query, ]ZKt1@4AY
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finalObject[] parameters){ xPDA475Cw3
return getHibernateTemplate f UF;SqT
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().findByNamedQuery(query, parameters); 2@R8P~^W
} ^/C$L8#
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publicList find(finalString query){ De
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return getHibernateTemplate().find V(2j*2R!
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(query); ~i }+P71
} w~$c= JO#
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publicList find(finalString query, finalObject lQdnL.w$.4
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parameter){ UROj9COv
return getHibernateTemplate().find d2A
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(query, parameter); C,{F0-D
} 7bonOt
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public PaginationSupport findPageByCriteria -OrY{^F
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(final DetachedCriteria detachedCriteria){ oI_oz0nHk
return findPageByCriteria h"u<E\g
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); llHc=&y#
} DHm[8 Qp
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public PaginationSupport findPageByCriteria +z:CZ(fb
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(final DetachedCriteria detachedCriteria, finalint 9Qzjqq:"Li
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startIndex){ cxXbo a
return findPageByCriteria r"{Is?yKe
~LawF_]6
(detachedCriteria, PaginationSupport.PAGESIZE, G&x'=dJ
tS\=<T
startIndex); &l.x:eD
} [3j$ 4rP
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public PaginationSupport findPageByCriteria T&1-eq>l
!}>eo2$r^
(final DetachedCriteria detachedCriteria, finalint ta&Q4v&-
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pageSize, koOy Z>
finalint startIndex){ p`>AnfG
return(PaginationSupport) uu}a:qrY
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getHibernateTemplate().execute(new HibernateCallback(){ w$gSj/
publicObject doInHibernate o" |O
]
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(Session session)throws HibernateException { `FUFK/7
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Criteria criteria = UhsO\ 9}qH
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detachedCriteria.getExecutableCriteria(session); p1Q/g Il
int totalCount = ]{YN{
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((Integer) criteria.setProjection(Projections.rowCount fO*)LPen.z
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()).uniqueResult()).intValue(); &oA~
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criteria.setProjection y:Z$LmPc<
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(null); ~\2;i]|
List items = 8{oZi]ob
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criteria.setFirstResult(startIndex).setMaxResults y'^F,WTM
'r~8
(pageSize).list(); P"b8!k?
PaginationSupport ps = WPIZi[hBs
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new PaginationSupport(items, totalCount, pageSize, (I[s3EnhS
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startIndex);
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return ps; 0}B?sNr
} mIvnz{_d
}, true); 47KNT7C
}
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public List findAllByCriteria(final rR\;G2p)
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DetachedCriteria detachedCriteria){ F'1k<V?
return(List) getHibernateTemplate 8yn4}`Nc@
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().execute(new HibernateCallback(){ ^_sQG
publicObject doInHibernate +,z)#
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(Session session)throws HibernateException { CI^[I\$&
Criteria criteria = +>!V]S
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detachedCriteria.getExecutableCriteria(session); n&$/Q$d&
return criteria.list(); uxb:^d?D!
} >VP5vkv=
}, true); pl|h>4af
} yplG18
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public int getCountByCriteria(final 6lsEGe
BKay*!'PX
DetachedCriteria detachedCriteria){ ->h5T%sn
Integer count = (Integer) %&h c"7/k
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getHibernateTemplate().execute(new HibernateCallback(){ Z5$fE7ba+
publicObject doInHibernate ~@D/A/|
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(Session session)throws HibernateException { U7h(-dV
Criteria criteria = RU|X*3";T
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detachedCriteria.getExecutableCriteria(session); >I^9:Q
return s7l23*Czl
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criteria.setProjection(Projections.rowCount rEM#D]k
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()).uniqueResult();
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} o/^1Wm=
}, true); <( EyXV
return count.intValue(); DZk1ZLz
} :IZ"D40m"
} moZm0`WR
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用户在web层构造查询条件detachedCriteria,和可选的 .T8K-<R
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Oaa"T8t
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PaginationSupport的实例ps。 z:}nBCmLV
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ps.getItems()得到已分页好的结果集 '3Q3lM'lh
ps.getIndexes()得到分页索引的数组 [E|uY]DR
ps.getTotalCount()得到总结果数 p$XKlg&
ps.getStartIndex()当前分页索引 (>7>3
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 :kG)sw7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 OfZN|S+~W
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 /.Q4~Hw%}
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一下代码重构了。 ;Gd~YGW^#
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我把原本我的做法也提供出来供大家讨论吧: #g9ZX16}
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首先,为了实现分页查询,我封装了一个Page类: Mvcfk$pA
java代码: qLK?%?.N<
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/*Created on 2005-4-14*/ ^4pto$#@O:
package org.flyware.util.page; ,hRN\Kt)p
(S/F)?
/** Nneo{j
* @author Joa 5?u}#zO
* :dnJY%/q
*/ KoBW}x9Jp
publicclass Page { 0. ;}]v
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/** imply if the page has previous page */ ',=g;
privateboolean hasPrePage; ,6"l (]0
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/** imply if the page has next page */ S#l5y%&
privateboolean hasNextPage; F-
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/** the number of every page */ I'!/[\_
privateint everyPage; Wf26
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/** the total page number */ ,kM)7!]N
privateint totalPage; o
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5iX!
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/** the number of current page */ l=m(mf?QBg
privateint currentPage; 04@cLDX8uB
E6MA?Ax&=
/** the begin index of the records by the current g@ith&*=h
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query */ ~mp0B9L%
privateint beginIndex; {6Au3gt/
5Av=3[kh"%
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/** The default constructor */ G4-z3e,crr
public Page(){ (p)!Mq
"^
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} ~$,qgf
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/** construct the page by everyPage jLVl4h&
* @param everyPage ~Ci{3j :]
* */ K\?]$dK5
public Page(int everyPage){ au@a8MP
this.everyPage = everyPage; `ldz`yu6++
} R^&q-M=O[
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/** The whole constructor */ o>]`ac0b}Y
public Page(boolean hasPrePage, boolean hasNextPage, !nf-}ze{
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q
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int everyPage, int totalPage, E8[T
int currentPage, int beginIndex){ Lxl_"kG
this.hasPrePage = hasPrePage; ]ZoPQUS?
this.hasNextPage = hasNextPage; 2t#L:vY
this.everyPage = everyPage; fxQN+6;
this.totalPage = totalPage; Vm1-C<V9
this.currentPage = currentPage; 'Prxocxq
this.beginIndex = beginIndex; IVxWxM*N<
} 2tQ`/!m>v$
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/** hVpCB,
* @return W7No ls{
* Returns the beginIndex. 9WG{p[
*/ ~.g3ukt
publicint getBeginIndex(){ )X+mV
return beginIndex; ?\=/$Gt
} a:STQk V
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/** |bv,2uW z
* @param beginIndex u'~;Y.@i'
* The beginIndex to set. YUWn;#
*/ vG41C k1
publicvoid setBeginIndex(int beginIndex){ +K",^6%1
this.beginIndex = beginIndex; S_(d9GK<
} ,L>
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/** uRV<?y%
* @return 256LH Y|6
* Returns the currentPage. 7*+]wEs
*/ xl9aV\W
publicint getCurrentPage(){ pL1i|O
return currentPage; OW;tT=ql
} /7c~nBU
22hSove.
/** W~n.Xeu{C
* @param currentPage ~:4kU/]
* The currentPage to set. >H][.@LyR
*/ m|tC24
publicvoid setCurrentPage(int currentPage){ w*7|dZk{
this.currentPage = currentPage; h!@,8y[B
} zt24qTKL
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/** SuBeNA[&
* @return XUMX*
* Returns the everyPage. gJN0!N'
*/ b,H[I!. %
publicint getEveryPage(){ UKd'+R]
return everyPage; R9vT[{!i
} '=E9En#@
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/** H;ZHqcUX
* @param everyPage |`k
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* The everyPage to set. ,Dmc2D
*/ M+>`sj
publicvoid setEveryPage(int everyPage){ Pf_F59"
this.everyPage = everyPage; -XK0KYhgW
} AIl4]F5I
rM}0%J'
/** od<b!4k~s
* @return pcS+o
* Returns the hasNextPage. _mE^rT
*/ rnFM/GAy
publicboolean getHasNextPage(){ le)DgIT>=
return hasNextPage; _ o6G6e,
} Lm*VN~2
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/** 7v}x?I
* @param hasNextPage /c#`5L[
* The hasNextPage to set. D87|q4
*/ jn%kG ~]'Q
publicvoid setHasNextPage(boolean hasNextPage){ 'm=*u
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this.hasNextPage = hasNextPage; l3o#@sz:
} .lG5=Th!
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/** H[Q_hY[>V
* @return DC+wD
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* Returns the hasPrePage. f&@BKx
*/ )ukpJ z""
publicboolean getHasPrePage(){ i8X`HbmN
return hasPrePage; %GEJnJ
} )vB2!H/
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/** hqSJ(gs{
* @param hasPrePage ]uL+&(cr
* The hasPrePage to set. QrG`&QN
*/ .ae O}^
publicvoid setHasPrePage(boolean hasPrePage){ =nUW'
this.hasPrePage = hasPrePage; ,3DXFV'uxb
} !G5a*8]
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/** 1n*W2:,z
* @return Returns the totalPage. hPhZUL%
* ;!@EixN-YH
*/ 7cg*|E@
publicint getTotalPage(){ U_yE&6 T
return totalPage; Wo$%9!W
} +A_J1iJ<
h #Z4pN8T3
/** 'fwU]Hm
* @param totalPage 'Yy&G\S
* The totalPage to set. `'_m\uo
*/ BfTcI)
publicvoid setTotalPage(int totalPage){ Q-TV*FD.
this.totalPage = totalPage; <oMUQ*OtV
} cF T 9Lnz
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} >"3>s%
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2i#Sn' 1
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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 :B*}^g
2h30\/xkU
个PageUtil,负责对Page对象进行构造: woH)0v
java代码: pj|pcv^
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/*Created on 2005-4-14*/ s'P( ,!f
package org.flyware.util.page; |Yi)"-
Wa/g`}
import org.apache.commons.logging.Log; XhU@W}}
import org.apache.commons.logging.LogFactory; m@Ev~~;
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/** I~eSZ?$s#
* @author Joa VU|dV\>
* &7?R+ZGo
*/ "7%:sty
publicclass PageUtil { 3cl9wWlJ_E
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privatestaticfinal Log logger = LogFactory.getLog FXKF\1`(H
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(PageUtil.class); $e%2t^ i.g
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/** "+ "{+k5t
* Use the origin page to create a new page TrVWv
* @param page
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* @param totalRecords \@a$'
* @return 46jh-4)<
*/ iSK+GQ~
publicstatic Page createPage(Page page, int ^o?S M^
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totalRecords){ $ls[|N:y0l
return createPage(page.getEveryPage(), S|AM9*k9
p(SRjQt
page.getCurrentPage(), totalRecords); z:Sigo_z[
} mbl]>JsQD
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/** Ths_CKwgWY
* the basic page utils not including exception 0:Xxl76v4
;d.K_P
handler v'2[[u{7*
* @param everyPage #1'\.v
* @param currentPage 9D\4n
* @param totalRecords pC,o2~%{
* @return page +H/jK @
*/ SD\=
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publicstatic Page createPage(int everyPage, int "e3["'
bte~c
currentPage, int totalRecords){ <hnCUg1
everyPage = getEveryPage(everyPage); HY;o^drd
currentPage = getCurrentPage(currentPage); t,)N('m}=
int beginIndex = getBeginIndex(everyPage, u#7+U\
8$N8}q%
currentPage); ~`;rNnOT3
int totalPage = getTotalPage(everyPage, \/7i-B]G7
GnXNCeE`
totalRecords); v
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boolean hasNextPage = hasNextPage(currentPage, %WG9 dYdS
.ujT!{>v/
totalPage); _;A $C(
boolean hasPrePage = hasPrePage(currentPage); [mxTa\
ExSe=4q#
returnnew Page(hasPrePage, hasNextPage, /T^ JS
everyPage, totalPage, ylf[/='0K
currentPage, NBh%:tu7M
pb60R|k
beginIndex); g_*T?;!.U
} 5(2|tJw-H;
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privatestaticint getEveryPage(int everyPage){ !
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return everyPage == 0 ? 10 : everyPage; 9_ICNG%
} NW|f7
ItX
bok.j
privatestaticint getCurrentPage(int currentPage){ ? Q@kg
return currentPage == 0 ? 1 : currentPage; hli|B+:m"
} fHrt+_Zn|
+,+vkpL-%
privatestaticint getBeginIndex(int everyPage, int %HQ.|
Ou>u%
currentPage){ {cK^,?x
return(currentPage - 1) * everyPage; j83? m
} <q)4la
F1;lQA*7K.
privatestaticint getTotalPage(int everyPage, int ,iNv'
_s,ao'/
totalRecords){ c;f!!3&
int totalPage = 0; _eSdnHWx
r90+,aLM#?
if(totalRecords % everyPage == 0) 5 /",<1
totalPage = totalRecords / everyPage; ] U@o0
else 2 gq$C"
totalPage = totalRecords / everyPage + 1 ; }F6<w{|
djQv[Vc{
return totalPage; )'4P.>!!aQ
} Mpue
h[KvhbD3
privatestaticboolean hasPrePage(int currentPage){ lA!"z~03*
return currentPage == 1 ? false : true; D'<VYl"/
} %\O#&=$E
O-vGyNxP|
privatestaticboolean hasNextPage(int currentPage, )O+}T5c=
@K223?c8l
int totalPage){ sRVIH A,
return currentPage == totalPage || totalPage == <%}QDO8\i
x} /,yaWZ
0 ? false : true; h!@|RW&}qX
} Zv]x'3J#Y
qL$a
c}`
^Jp&H\gI.
} 5FVndMM#y
<`X"}I3ba
$\o{_?}1
.9*wY0:
W+wA_s2&D
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 'k;4 j|<
[97:4.
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 rVvR!"//yH
'AGto'Yy;
做法如下: WtQ8X|\`
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 CfEmT8sa
_cTh#t ^
的信息,和一个结果集List: 5wB =>
java代码: ~0$NJrUy
:a8 YV!X
HD,xY4q&N
/*Created on 2005-6-13*/ #
?1Sm/5k`
package com.adt.bo; wHZW `
682Z}"I0
import java.util.List; dF0,Y?
H>Q%"|
import org.flyware.util.page.Page; c0c|z
Ym
7g=2Z[o
/**
N#V.1<Y
* @author Joa 2 &/v]
*/ ~AYN
publicclass Result { -aRU]kIf
gK#mPcn^
private Page page; YzosZ! L!<
nKR{ug>I)
private List content; ^Jb
H?
bQe^Px5
!.
/** g71[6<D
* The default constructor _(J&aY\
*/ s?8<50s
public Result(){ wIkN9
f
super(); Vc^HVyAx@n
} `&0Wv0D0
j Ja$a [
/** fA'qd.{f^
* The constructor using fields ,F&g5'
* NmK8<9`u
* @param page #T`t79*N
* @param content js1!9%BV
*/ 'c\iK=fl
public Result(Page page, List content){ &DqE{bBd!
this.page = page; bo.(zAz
this.content = content; r&-m=Kk$
} aA7=q=
TJE\A)|>g
/** G!4(BGx&
* @return Returns the content. f3`7tA
*/ sNun+xsf^
publicList getContent(){ A+@&"
return content; $R<Me
} dr4Z5mw"E
CctJFcEZ
/** S9HwIH\m
* @return Returns the page. MX@IHc
*/ `1 :{0p2q
public Page getPage(){ ~>9_(L
return page; j}b\Z9)!
} O25lLNmO
tabT0
/** 8[6o (
* @param content 2Sm}On
* The content to set. O-)-YVU
*/ j,]Y$B
public void setContent(List content){ !3T&4t
this.content = content; <\?wAjc,
} hY`\&@
0'nikLaKy
/** Ty88}V
* @param page ;c$ J=h]
* The page to set. F;^F+H
*/ 9mZ
publicvoid setPage(Page page){ =B.F;40
this.page = page; $1SUU F\.
} Q_l'o3
} @JdZ5Q
a22XDes=
LR"9D
XrZ*1V
V59(Z
2. 编写业务逻辑接口,并实现它(UserManager, <$JaWL
*hcYGLx
r
UserManagerImpl) I}R0q
java代码: K_&4D'
[=~ pe|8:
nT2)E&U6%
/*Created on 2005-7-15*/ =*Bl|;>6
package com.adt.service; *2jK#9"MP
X.:]=,aGW
import net.sf.hibernate.HibernateException; Ewg:HX7<(
v$^Z6>vVI
import org.flyware.util.page.Page; }f2r!7:x
5atYOep
import com.adt.bo.Result; ~K@'+5Pc
L@fY$Rw
/** u{L!n$D7
* @author Joa =FD;~
*/ }NB}"%2
publicinterface UserManager { D_Bb?o5
7%sdtunf`
public Result listUser(Page page)throws QE7V.
>J_p
={u0_j
W
HibernateException; 8g7<KKw
K<>sOWZ'S
} Po%(~ )S>
)+fh-Ui
RD.V'`n"
--DoB=5%8
%; D.vKoh
java代码: b".L_Ma1*
%.vVEy
N?.%?0l
/*Created on 2005-7-15*/ M+x,opl
package com.adt.service.impl; Si~vDQ7"
IY*EA4>
import java.util.List; 3)RsLI9
Qa.uMq
import net.sf.hibernate.HibernateException; Gw1@KKg
F;>!&[h}G
import org.flyware.util.page.Page; 9HX =T%
import org.flyware.util.page.PageUtil; zL J/5&
M.>l#4s,'
import com.adt.bo.Result; nWHa.H#
import com.adt.dao.UserDAO; ,#8e_3Z$
import com.adt.exception.ObjectNotFoundException; FKmFo^^0
import com.adt.service.UserManager; CoA6
}RP@!=
/** m1*O0Tg]"
* @author Joa *Aa?yg:=
*/ wKsT7c'
publicclass UserManagerImpl implements UserManager { ^53r/V }%
_(KbiEB{
private UserDAO userDAO; 2r ZxSg
/Js7`r=Rx
/** } GiHjzsR
* @param userDAO The userDAO to set. o-Ga3i 8
*/ "V}[':fen
publicvoid setUserDAO(UserDAO userDAO){ 2J;kSh1,L
this.userDAO = userDAO; NrJKbk^4u/
} d0,s"K7@
_x5 3g
A
/* (non-Javadoc) G}G#i`6o
* @see com.adt.service.UserManager#listUser P$-X)c$&
~b2wBs)r
(org.flyware.util.page.Page) s
S7c!
*/ c[ ]4n
public Result listUser(Page page)throws YGsWu7dG
NW&b&o
HibernateException, ObjectNotFoundException { "%x<ttLl
int totalRecords = userDAO.getUserCount(); *~x/=.}
if(totalRecords == 0) mOlI#5H
throw new ObjectNotFoundException :dqn h
ih;]nJ]+-
("userNotExist"); Kp,M"Y
page = PageUtil.createPage(page, totalRecords); TG5XSy
List users = userDAO.getUserByPage(page); I2nhqJy^
returnnew Result(page, users); Ck|8qUz-
} ~7Tc$
"I
Mwr"~?\\
} G"XVn~]
>#y^;/bb
[bk?!0]aV
AD<q%pu&H?
mFZ?hOyP.
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5EebPXBzB
6 M*O{f
询,接下来编写UserDAO的代码: E 0?iXSJ
3. UserDAO 和 UserDAOImpl: 6<ZkJ:=
java代码: y7i*s^ys{
!!? Mw
wL:flH@
/*Created on 2005-7-15*/ }dd8N5b
package com.adt.dao; "PpN0Rr
SK#(#OQoh
import java.util.List; ={xE!"
9c6gkt9eB
import org.flyware.util.page.Page; :d#VE-e
%eO0wa$a
import net.sf.hibernate.HibernateException; XnWr5-;
vsl]92xI
/** sH[ROm
* @author Joa A'&K/) Z
*/ _<OSqE
publicinterface UserDAO extends BaseDAO { 3S}Pm2D2
2P@sn!*{1
publicList getUserByName(String name)throws F
70R1OYU
&?yZv{
HibernateException; \hEN4V[
0p!>JQ]m
publicint getUserCount()throws HibernateException; 7*Ej. HK
"pRtczxOgR
publicList getUserByPage(Page page)throws YS *9t
Q{
ZGKu>yM
HibernateException; 5X:*/FuS@
?3.b{Cq{-
} j4uvS!
K8UP,f2
zp%Cr.)$
1NgCw\
m1Mt#@,$
java代码: \S!e![L/
W1|0Yd ;P
Dw<bn<e-
/*Created on 2005-7-15*/ .jk@IL
package com.adt.dao.impl;
`yH<E+
<BMXCk
import java.util.List; 'g
m0) r
/! "|_W|n
import org.flyware.util.page.Page; r'HtZo$^R
l^pA2yh|
import net.sf.hibernate.HibernateException; &p4&[H?
import net.sf.hibernate.Query; ;E3>ay6m8
*&^:T~|=!
import com.adt.dao.UserDAO; Ne[7gxpu
M$>1L
/** ZOeQ+j)|I
* @author Joa #0P$M!%
*/ Kk-S}.E
public class UserDAOImpl extends BaseDAOHibernateImpl %R}.#,Suo
P'Ux%Q+B>
implements UserDAO { rLI8pA|.
#AL=f'2=f
/* (non-Javadoc) "2)H'<
* @see com.adt.dao.UserDAO#getUserByName $JMXV
hp 5|@
(java.lang.String) "J[K 3
*/ H1QJk_RL
publicList getUserByName(String name)throws '":lB]hS
!O:y@
HibernateException { ~,oMz<iMV
String querySentence = "FROM user in class _lGdUt 2
&3J_^210
com.adt.po.User WHERE user.name=:name"; XkXHGDEf 1
Query query = getSession().createQuery ebUBrxZX
^h~x)@=
(querySentence); iw8yb;|z;A
query.setParameter("name", name); +wN^c#~7
return query.list(); gy 3i+J
} M42Ssn)
LWz&YF#T-
/* (non-Javadoc) #><.oreXq
* @see com.adt.dao.UserDAO#getUserCount() smRE!f*q
*/ Z{ X|6.
publicint getUserCount()throws HibernateException { $o0iLFIX/
int count = 0; WJkZ!O$"j
String querySentence = "SELECT count(*) FROM V )x$|!(
QLEKsX7p>
user in class com.adt.po.User"; VC\ S'z
Query query = getSession().createQuery $Q96,rb}k;
u'|4?"uz
(querySentence); M<.d8?p )
count = ((Integer)query.iterate().next a!<8\vzg
uW@oyZUj
()).intValue(); %,6#2X nX%
return count; T92UeG
} toya fHf
)z73-M V"
/* (non-Javadoc) )Ch2E|C?=8
* @see com.adt.dao.UserDAO#getUserByPage u09:Z{tL;@
{mZC$U'
(org.flyware.util.page.Page) z(_Ss@ $
*/ r@+ri1c
publicList getUserByPage(Page page)throws G7qG$wd8h
Tx|Ir+f6L
HibernateException { yp KUkH/
String querySentence = "FROM user in class )vjh~ybZ
F)&@P-9+
com.adt.po.User"; XC0bI,Fu,
Query query = getSession().createQuery wkA+j9.
R7$:@<:g
(querySentence); =j5MFX.-o
query.setFirstResult(page.getBeginIndex()) \O*-#} ~\
.setMaxResults(page.getEveryPage()); OGde00
return query.list(); kP#B5K_U|
} q>$ev)W
-(bXSBs#
} s \;" X
)6,de2Pb
^?0DP>XA
3L833zL
hAYTj0GZ
至此,一个完整的分页程序完成。前台的只需要调用 # {w9s0:
kbTm^y"
userManager.listUser(page)即可得到一个Page对象和结果集对象 J
pFfzb
@R/07&lBR
的综合体,而传入的参数page对象则可以由前台传入,如果用 D7lK30
$@^pAP
webwork,甚至可以直接在配置文件中指定。 r=5{o1"
(]0%}$Fo
下面给出一个webwork调用示例: OMWbZ>jB
java代码: ])|d"[ur=
Cdas P9"1
?EJD?,}
/*Created on 2005-6-17*/ 2^mJ+v<
package com.adt.action.user; co~Pyj
&Sl[lXE
import java.util.List; LJk@Vy <?
,TXTS*V?
import org.apache.commons.logging.Log; <(-= 'QA
import org.apache.commons.logging.LogFactory; o7J
import org.flyware.util.page.Page; tw^,G(
;A|-n1e>Hc
import com.adt.bo.Result; }4Tc
import com.adt.service.UserService; ;3d"wW]}7K
import com.opensymphony.xwork.Action; /tP|b_7O
|zQ4u
/** fBRo_CU8!
* @author Joa X9p.gXF
*/ "}q@Y=
publicclass ListUser implementsAction{ $nb[G$
J6U$qi
privatestaticfinal Log logger = LogFactory.getLog kSR\RuY*
RA KFU
(ListUser.class); 7![,Q~Fy
Y' %^NP}o
private UserService userService; )Y2{_ bx4"
POdUV
private Page page; ^cczJOxB
"}pNe"ok
privateList users; 1QLbf*zeIW
}._eIx"
/* Svondc
4
* (non-Javadoc) jp0<pw_
* Y( 3Bp\6
* @see com.opensymphony.xwork.Action#execute() FrTi+& <
*/ }dp=?AFg
publicString execute()throwsException{ EQf[,
Result result = userService.listUser(page); ep2k%?CX 1
page = result.getPage(); ny`#%Vs
users = result.getContent(); Tav*+
return SUCCESS; m=}B,']O
} `Jzp Sw
l-SAC3qhG
/** { jhr<
* @return Returns the page. a4XU?-sUh
*/ XmEq2v
public Page getPage(){ W7U2MqQ
return page; tS|(K=$
} w*oeK
c2&q*]?l;
/** So0f)`A
* @return Returns the users. hS)'a^FV
*/ gREzZ+([
publicList getUsers(){ ig/%zA*Bo
return users; KTP8?Q"n0
} CaL\fZ
pov)Z):}G<
/** a{R%#e\n
* @param page nPye,"A Ol
* The page to set. ;`^WGS(3.%
*/ m^bNuo
publicvoid setPage(Page page){ B oC5E#;G
this.page = page; ~S8* t~
} i70wrW#k
Cn "s`
q
/** BDR.AZ
* @param users PK0%g$0
* The users to set. 22.8PO0
*/ D^=J|7e
publicvoid setUsers(List users){ k}
|
this.users = users; dvt9u9Vg=
} 4iKgg[)7`=
8C67{^`::
/** b/C`Jp
* @param userService )?X-(4
* The userService to set. S/4^ d &Gr
*/ 0l-Ef1
publicvoid setUserService(UserService userService){ @te!Jgu{
this.userService = userService; ?XA2&
} rvnT6Ve
} @wE5S6! B\
Mf&{7%
vTlwRG=5
m^GJuPLW
:}@g6
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 1T-8K
r
J6L K
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 fjs
[f'L
6~1|qEe6I
么只需要: gx\&_)w N
java代码: \E%'Y
E )5E$
XqW@rU
<?xml version="1.0"?> `kZ@Zmj#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _Jme!Oaa
lzYnw)Pv
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 9hOJvQ2U]
9Hc$G{[a
1.0.dtd"> dt`{!lts'
[&&1j@LQ*
<xwork> ReM=eS
ML(
Eo
<package name="user" extends="webwork- |aT| l^2R@
b0Kc^uj5
interceptors"> @>E2?CV
6y6<JR-V2k
<!-- The default interceptor stack name b+f'[;
o[cV1G
--> )FpZPdN+h
<default-interceptor-ref i1>-QDYnJ
]K/DY Do-
name="myDefaultWebStack"/> ($}`R
xj1@
m3mp/g.>
<action name="listUser" /XhIx\40l
&<UMBAS
class="com.adt.action.user.ListUser"> |b|&XB_<]Z
<param 1$%V{4bJ
>]W)'lnO
name="page.everyPage">10</param>
*X,
/7C
<result 2U; t(,dn'
,=|ZB4HA
name="success">/user/user_list.jsp</result> EpFQ|.mQ
</action> `kU/NKq
{6~l$
</package> IaT$6\>
%YSu8G_t
</xwork> `~ * @q!
VxXzAeM
US%^#D q
N9vP7
>&p0d0
'ul~7h;n
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 =Q[b'*o7
qfK`MhA}
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 .F(i/)vaq|
H8`(O"V
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 rORZerM
]@0NO;bK>F
Vgyew9>E
sH?/E6
k:#P|z$UD
我写的一个用于分页的类,用了泛型了,hoho DNj"SF(J
X_g 3rv1J
java代码: W"k8KODOY
N1}={yF.fQ
8krpowVs~
package com.intokr.util; aN $}?
sSQs#+&=[
import java.util.List; bLd#xXl
3Bx:Ntx<
/** mUz\ra;z
* 用于分页的类<br> ?1[\!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> t6A:ZmG_
* p$x{yz3
* @version 0.01 rJ!{/3e
* @author cheng (<Th=Fns?
*/ \0H's{uek
public class Paginator<E> { v!FMs<
privateint count = 0; // 总记录数 K&U7H:
privateint p = 1; // 页编号 )"m!YuS Y
privateint num = 20; // 每页的记录数 3,Q^&
1
privateList<E> results = null; // 结果 ?&^?-S% p
ryc& n5
/** 5n
^TRB
* 结果总数 z8J."27ND
*/ ]wWPXx[>/
publicint getCount(){ fS"Hr 0
return count; j*
*s^Sg
} Eb=#9f%y>&
XbZ*&
publicvoid setCount(int count){ -Z?Vd!H:
this.count = count; (} 5S
} /De^
}h}<!s
/** X2xuwA
* 本结果所在的页码,从1开始 1<<kA:d
* bI y sl
* @return Returns the pageNo. [M%9_CfZOy
*/ nxJee=qH
publicint getP(){ j}AFE
return p; 2EK%N'H
} n?:=
pMJ1v
/** rJ o"fx
* if(p<=0) p=1 S inl
* 033T>qY
* @param p P/ oXDI8
*/ -.|4Y#b:&
publicvoid setP(int p){ 62>zt2=
if(p <= 0) 7E @+
p = 1; uyF|O/FC
this.p = p; \M"UmSB o
} 7 ua6l[c
oiH|uIsqR
/** i0s6aAhgJ
* 每页记录数量 $j5,%\4<
*/ =U.
b% uC
publicint getNum(){ Ji;mHFZ*FU
return num; gs
W0
} b`_w])Y@
vwr74A.g0
/** PjIeZ&p
* if(num<1) num=1 sgr=w+",Q
*/ 2 /y}a#s
publicvoid setNum(int num){
pAu72O?
if(num < 1) jb /8?7
num = 1; CWO=0_>2
this.num = num; j4R 4H;
} 'lS`s(
^<0IB#dA
/** SjdZyJa
* 获得总页数 IF@HzT;Q
*/ QI_59f>
publicint getPageNum(){ V5D`eX9
return(count - 1) / num + 1; ~B$b)`*
} htPqT,L
|8)Xc=Hz
/** fRm}S>Nibb
* 获得本页的开始编号,为 (p-1)*num+1 (H?ZSeWx
*/ M_``'gw
publicint getStart(){ +/?iCmW
return(p - 1) * num + 1; [^~7]2 i
} (}:C+p
'I
+@VYs*&&
/** <SVmOmJ-K
* @return Returns the results. <3hA!$o~
*/ jK8'T_Pah
publicList<E> getResults(){ k*-NsNPw$
return results; 7?)/>lx\>$
} XtBMp=7Oa
[$ :
public void setResults(List<E> results){ 4%*hGh=
this.results = results; cbKL$|
} ["3df>!f
&B!%fd.'
public String toString(){ ]#<
StringBuilder buff = new StringBuilder qvt-
eSl-9
^
(); R#4^s
buff.append("{"); jnoL2JR[=-
buff.append("count:").append(count); S*%iiD)
buff.append(",p:").append(p);
wAbp3h X
buff.append(",nump:").append(num); H]&!'\aUz
buff.append(",results:").append iilyw_$H
YDiN^q7
(results); C]`eH*z~8
buff.append("}"); ${U6=
return buff.toString(); )u@t.)ChAV
} >uHS[ _`nM
n_$yV:MuT!
} J"[3~&em
015Owi
^i<}]c_|f