Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 D=)qd@,K
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 {JM3drnw
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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 <)+;Bg
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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 f5R%F~
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分页支持类: iHWt;]
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java代码: V3_qqz}`r
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package com.javaeye.common.util; 17VNw/Y
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import java.util.List; zu1gP/
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publicclass PaginationSupport { +EZr@
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publicfinalstaticint PAGESIZE = 30; QzYaxNGv
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privateint pageSize = PAGESIZE; r<*Y1;7H'
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privateList items; +PO& z!F
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privateint totalCount; d%Ku'Jy
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privateint[] indexes = newint[0]; CF5%&B
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privateint startIndex = 0; $-)y59w"
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public PaginationSupport(List items, int [{J1b
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totalCount){ tdC
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setPageSize(PAGESIZE); XB%`5wwd
setTotalCount(totalCount); n4
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setItems(items); }Z`@Z'
setStartIndex(0); 4;w#mzd
} _xdttO^N
;~s@_}&
public PaginationSupport(List items, int 73M;-qnU
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totalCount, int startIndex){ b;I!CyD
setPageSize(PAGESIZE); Bc#6mO-
setTotalCount(totalCount); +Jc-9Ko\c;
setItems(items); '`p0T%w
setStartIndex(startIndex); vaZ?>94
} BimM)4g
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public PaginationSupport(List items, int |nO}YU\E
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totalCount, int pageSize, int startIndex){ D7$xY\0r
setPageSize(pageSize); Sq2yQSd
setTotalCount(totalCount); iainl@3Qj
setItems(items); (yz8}L3
setStartIndex(startIndex); OZh+x`' #
} ,@2d4eg4
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7
publicList getItems(){ POQ1K
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return items; LZu_-I
} 5TdI
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publicvoid setItems(List items){ M~!LjJg;
this.items = items; B?_ujH80m
} m<22E0=g
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publicint getPageSize(){ @aGS~^Uh
return pageSize; Mq,_DQ
} vGPaW YV
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publicvoid setPageSize(int pageSize){ ,#-^
this.pageSize = pageSize; 9a_(_g>S
} /t?(IcP5
@i:_JOl
publicint getTotalCount(){ VAR/"
return totalCount; 6UJBE<ntj
}
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publicvoid setTotalCount(int totalCount){ 4^B:Q9B)
if(totalCount > 0){ B6vmBmN
this.totalCount = totalCount; ';7|H|,F
int count = totalCount / 8 _[f#s`)
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pageSize; >Y/1%Hp9
if(totalCount % pageSize > 0) FJ&zU<E
count++; /7zy5
indexes = newint[count]; s/'gl
for(int i = 0; i < count; i++){ & ~[%N
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indexes = pageSize * Wkv**X}
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i; J XnPKAN
} c5rQkDW
}else{ `o*g2fW!
this.totalCount = 0; |wj/lX7y
} egi?Qg
} 2jx+q
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publicint[] getIndexes(){ efP2 C\
return indexes; (;h]'I@
} %jM|*^\%
L7%'Y}1e.
publicvoid setIndexes(int[] indexes){ z:R2Wksg
this.indexes = indexes; 4%j&]PASa1
} |qNrj~n@
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publicint getStartIndex(){ Sb[rSczS~
return startIndex; @;,O V&XYn
} )Bk?"q
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publicvoid setStartIndex(int startIndex){ (^Do#3
if(totalCount <= 0) 0QIocha
this.startIndex = 0; .^.UJo;4G
elseif(startIndex >= totalCount) 90aPIs-
this.startIndex = indexes 1,`x1dcO!A
%dT%r=%Y
[indexes.length - 1]; Pjb9FCA'
elseif(startIndex < 0) Azz]TO
this.startIndex = 0; L}a3!33)C
else{ IL:"]`f*
this.startIndex = indexes A1ebXXD)
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[startIndex / pageSize]; D+o.9I/{
} O\KAvoQ%s
} c)6Y.[).
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publicint getNextIndex(){ pmW=l/6+V3
int nextIndex = getStartIndex() + Ft.BfgJ$
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pageSize; JcVq%~{M
if(nextIndex >= totalCount) HIa$0g0J
return getStartIndex(); Em"X5>;4
else '/
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return nextIndex; :M[E-j;
} 0RSa{iS*A
4!}fCP ty
publicint getPreviousIndex(){ >6DY3\
int previousIndex = getStartIndex() - o"1us75P
}lb.3fqiA
pageSize; #Aan v
if(previousIndex < 0) 0~1P&Qs<
return0; VDmd+bvJV
else c\b>4 &n
return previousIndex; !Z'm@,+
} +li^0+3-'
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} %-'U9e KN
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抽象业务类 oV!9B -<
java代码: 5~"=Fm<uD
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/** 0?h .X=G
* Created on 2005-7-12 (_08?cN
*/ `WW0~Tp3
package com.javaeye.common.business; }I`|*6Up
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import java.io.Serializable; 4QVd{
import java.util.List; M1M]]fT0ME
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import org.hibernate.Criteria; ,/ : )FV
import org.hibernate.HibernateException; &L?Dogo
import org.hibernate.Session; ;hZ@C!S:
import org.hibernate.criterion.DetachedCriteria; 5nn*)vK {
import org.hibernate.criterion.Projections; Bm7GU`j"
import -?'CUm*Od
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org.springframework.orm.hibernate3.HibernateCallback; f\^QV
import E{ ,O}
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org.springframework.orm.hibernate3.support.HibernateDaoS XHg%X
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upport; ~EM];i
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import com.javaeye.common.util.PaginationSupport; Mww]l[1'EL
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public abstract class AbstractManager extends z,7^dlT
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HibernateDaoSupport { uSQ*/h-<)0
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privateboolean cacheQueries = false; X m3t
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privateString queryCacheRegion; Wd}mC<rv1
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publicvoid setCacheQueries(boolean >`uS NY"tO
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cacheQueries){ ZkJM?Fzq
this.cacheQueries = cacheQueries; IXN4?=)I
} M5V1j(URE
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publicvoid setQueryCacheRegion(String A!kyga6F5
Mt Z(\&~
queryCacheRegion){ QBy*y $
this.queryCacheRegion = D=>^m=?0
+;Gl>$
queryCacheRegion; ~e+w@ lK
} Q=8
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publicvoid save(finalObject entity){ iFA"m;$
getHibernateTemplate().save(entity); *La =7y:
} M::iU_
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publicvoid persist(finalObject entity){ |7$h@KF=S
getHibernateTemplate().save(entity); TH!8G,(w
} pQ Y>
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publicvoid update(finalObject entity){ 's?F ip
getHibernateTemplate().update(entity); WLLv a<{
} J":9
@;}H<&"
publicvoid delete(finalObject entity){ }$1;<
getHibernateTemplate().delete(entity); Ag6
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} }6>J
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publicObject load(finalClass entity, af(JoX*U
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finalSerializable id){ rk |(BA
return getHibernateTemplate().load b2e a0
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(entity, id);
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}
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publicObject get(finalClass entity, %},G(>
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finalSerializable id){ J\'5CG
return getHibernateTemplate().get rb'Gve W[
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(entity, id); \cP'#jZz
} }GDG$QI]K&
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publicList findAll(finalClass entity){ 0Zh
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return getHibernateTemplate().find("from 8M9\<k6
^&H=dYcV>/
" + entity.getName()); A'1AU:d
} R?~h7 d
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publicList findByNamedQuery(finalString ~+egu89'TU
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namedQuery){ tC:,!4 P$
return getHibernateTemplate TrU@mYnE
\{zAX~k6
().findByNamedQuery(namedQuery); bV*zMoD#
} A9Wqz"[
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publicList findByNamedQuery(finalString query, Gc!8v}[7J
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finalObject parameter){ %*c|[7Z~V
return getHibernateTemplate (iOCzZ6S
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().findByNamedQuery(query, parameter); kO_XyC4(
} N"RYM~c7
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publicList findByNamedQuery(finalString query, ;nKHm
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finalObject[] parameters){ SM+fG: 4d
return getHibernateTemplate kdh9ftm*\
@1?]$?u&
().findByNamedQuery(query, parameters); [Cqqjv;_
} uQ]]]Z(H'
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publicList find(finalString query){ !5%5]9'n@*
return getHibernateTemplate().find asN
}
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(query); s.^9HuM
} hdtnC29$
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publicList find(finalString query, finalObject 1DLG]-j}
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parameter){ 4ylDD|) rO
return getHibernateTemplate().find AY'?Xt
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(query, parameter); +^ DRto=
} +1Rrkok
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public PaginationSupport findPageByCriteria !x$:8R
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(final DetachedCriteria detachedCriteria){ 72ViPWW
return findPageByCriteria Kq 4<l
n_aNs]C9R
(detachedCriteria, PaginationSupport.PAGESIZE, 0); W0MnGzZ
} %7>AcTN~
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public PaginationSupport findPageByCriteria CQjZAv
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(final DetachedCriteria detachedCriteria, finalint Y3$PQwn
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startIndex){
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return findPageByCriteria {jM<t
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(detachedCriteria, PaginationSupport.PAGESIZE, |\%F(d330
3> \fP#oQ
startIndex); C8qTz".5$
} 0L0Jc,(F+
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public PaginationSupport findPageByCriteria @?3vRs}h
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(final DetachedCriteria detachedCriteria, finalint ]bN&5.|
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pageSize, ?S@R~y0K
finalint startIndex){ <Hh5u~
return(PaginationSupport) `[@^m5?b-
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getHibernateTemplate().execute(new HibernateCallback(){ @0ov!9]Rw-
publicObject doInHibernate &cu] vw
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(Session session)throws HibernateException { ;Lsjh#
Criteria criteria = GL5^_`n
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detachedCriteria.getExecutableCriteria(session); D#d8 ^U
int totalCount = tCbr<Ug
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((Integer) criteria.setProjection(Projections.rowCount eMN+qkvH
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()).uniqueResult()).intValue(); L7Qo-
criteria.setProjection ]D{c4)\7C|
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(null); 2~M;L&9-
List items = eA1k)gjE
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criteria.setFirstResult(startIndex).setMaxResults 3V/_I<y
xHv|ca.E
(pageSize).list(); x[PEn
PaginationSupport ps = q8?=*1g
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new PaginationSupport(items, totalCount, pageSize, #juGD9e
7sud/*+F
startIndex); Sf'i{xye
return ps;
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} v~V;+S=gz
}, true); X:G&5
} QJ a4R
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public List findAllByCriteria(final B:O+*3j
'!wPnYT@D
DetachedCriteria detachedCriteria){ ^V<J69ny|9
return(List) getHibernateTemplate 6%ZHP?
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().execute(new HibernateCallback(){ 1UW s_|X!
publicObject doInHibernate e(}oq"'z
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(Session session)throws HibernateException { N<aB)</
Criteria criteria = d&aBs++T
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detachedCriteria.getExecutableCriteria(session); S)"##-~`T
return criteria.list(); YKP=0 j3,
} |?x^8e<*
}, true); 7$+P|U
} >oft :7p
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public int getCountByCriteria(final z}>4,d
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DetachedCriteria detachedCriteria){ -l-AToO4
Integer count = (Integer) =<[7J]%
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getHibernateTemplate().execute(new HibernateCallback(){ xw4ey<"I
publicObject doInHibernate m!#_CQ:
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(Session session)throws HibernateException { !~K=#"T
Criteria criteria = \R8 6;9ov
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detachedCriteria.getExecutableCriteria(session); DH\wDQ
return a?zR8$t|
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criteria.setProjection(Projections.rowCount Q&u>7_, Du
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()).uniqueResult(); MxY50^}(
} B;eW/#`
}, true); [urH a
return count.intValue(); )UR1E?'
} J#6LSD@(O
} n&_YYEHx
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用户在web层构造查询条件detachedCriteria,和可选的 }US7Nw
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 &}zRH}s;
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PaginationSupport的实例ps。 n<{aPLQ
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ps.getItems()得到已分页好的结果集 M} O[`Fx{W
ps.getIndexes()得到分页索引的数组 s,84*6u
ps.getTotalCount()得到总结果数 %z1{Kus
ps.getStartIndex()当前分页索引 z8b
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ps.getNextIndex()下一页索引 +``>,O6
ps.getPreviousIndex()上一页索引 d2ohW|
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 6yN"
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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 Am#m>^!qb
gk"mr_03
一下代码重构了。 D2Y&[zgv
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我把原本我的做法也提供出来供大家讨论吧: `Gf{z%/
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首先,为了实现分页查询,我封装了一个Page类: y0;,dv]
java代码: 8,=G1c
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/*Created on 2005-4-14*/ iNt 4>
package org.flyware.util.page; HH7[tGF
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/** NzAQ@E2d:
* @author Joa Hr8\QgD<4
* /;DjJpwf0
*/ ^,Xa IP+[
publicclass Page { 60'6/3
8AryIgy>@
/** imply if the page has previous page */ D^nxtuT*
privateboolean hasPrePage; >Z}@7$(7!~
B-$+UE>%
/** imply if the page has next page */ XHy?
privateboolean hasNextPage; Y7-*2"!
4*iHw+%mq
/** the number of every page */ 9-b 8`|s
privateint everyPage; R^w}o,/
M]1;
/** the total page number */ GN0duV
privateint totalPage; N. jA 8X
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/** the number of current page */ (e(Rr4
privateint currentPage; )R~a;?T_c0
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rx:
/** the begin index of the records by the current +1x)z~q=
>ZX|4U[$P
query */ jSB'>m]
privateint beginIndex; 1ADv?+j)A/
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/** The default constructor */ wajZqC2yg
public Page(){ .W$
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)'`CC>Q
} YN/u9[=`
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/** construct the page by everyPage `T=1<Tw c
* @param everyPage a/34WFC
* */ 5.dl>,
public Page(int everyPage){ KhrFg1|
this.everyPage = everyPage; *(icR
} XwtAF3oz
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/** The whole constructor */ \ p3v#0R{
public Page(boolean hasPrePage, boolean hasNextPage, h<)yJh
)&Mq,@
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int everyPage, int totalPage, 9Yn)t#G'`F
int currentPage, int beginIndex){ y=#j`MH{>
this.hasPrePage = hasPrePage; e]+7DE
this.hasNextPage = hasNextPage; w
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this.everyPage = everyPage; z#RuwB+
this.totalPage = totalPage; 2qlIy
this.currentPage = currentPage; {a.
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this.beginIndex = beginIndex; {gw[%[ZM
} pD[pTMG@$
t?HF-zQ
/** # v+;:
* @return FJ}gUs{m
* Returns the beginIndex. -qfnUh
*/ $,@JYLC2
publicint getBeginIndex(){ y`6\L$c
return beginIndex; Gp8psH
} 7C?E z%a@
Tv1]v.
/** ;5N41_hG
* @param beginIndex ^;4YZwW5w
* The beginIndex to set. a5)JkC
*/ 1U'ZVJ5bpK
publicvoid setBeginIndex(int beginIndex){ fq=:h\\G
this.beginIndex = beginIndex; e+{BJN
vz
} lA]N04 d
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/** m d_g}N(C
* @return me:iQ.g
* Returns the currentPage. \+9;!VWhl
*/ 5/,Qz>QE[
publicint getCurrentPage(){ _-RyHgX
return currentPage; 8RU.}PD
} =gs~\q
`|,Bm|~:
/** {pC\\}
* @param currentPage zQ_z7FJCB
* The currentPage to set. Zt_r9xs>
*/ &}E:jt}
publicvoid setCurrentPage(int currentPage){ 2qjyFTT
this.currentPage = currentPage; DLXL!-)z
} 6<PW./rk:
f7
wmw2
/** o[oqPN3$Y
* @return x)$2nonM
* Returns the everyPage. !?b/-~o7S
*/ ki#bPgT
publicint getEveryPage(){ )'t&q/Wn
return everyPage; 5D
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} 8gAu7\p}
)P%4:P
/** E<k^S{
* @param everyPage fdLBhe#9M
* The everyPage to set. 9(Jy0]E~
*/ R(`]n!V2
publicvoid setEveryPage(int everyPage){ =|"=l1
this.everyPage = everyPage; w&5/Zh[~~L
} ntZ~m
"[.ne)/MC
/** +KP_yUq[
* @return fK"iF@=Z`
* Returns the hasNextPage. qX?[mdCHZ
*/
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publicboolean getHasNextPage(){ >4c` UW
return hasNextPage; YD9!=a$
} X.eB ;w/}
e5 3,Rqi)@
/** TRy^hr8~
* @param hasNextPage Fpf><Rn
* The hasNextPage to set. G A EZY
*/ 7"a4/e;^
publicvoid setHasNextPage(boolean hasNextPage){ #Wk5E2t
this.hasNextPage = hasNextPage; *6P'q4)
} e=L*&X
\XDmK
/** [8z&-'J=
* @return cJ/4Gl
* Returns the hasPrePage. 8)?_{
*/ #N9d$[R*
publicboolean getHasPrePage(){ N%u
return hasPrePage; rs_h}+6"s
} .
pP7"E4]
,cD1{T\
/** L;lk.~V4T
* @param hasPrePage 32^#RlSu8
* The hasPrePage to set. @,e8t BL
*/ 7>mhK7l
publicvoid setHasPrePage(boolean hasPrePage){ Wc\+x1 :8
this.hasPrePage = hasPrePage; ZB0+GG\
} S<pkc8
CIy^`2wq
/** LihdZ )
* @return Returns the totalPage. E-F5y
* R\y'_S=#a
*/ O5OXw]
publicint getTotalPage(){ }hq^+fC?
return totalPage; #g{Mne
} v2=/[E@
;W6-i2?
/** Vd<K4Tk
* @param totalPage o3\,gzJ
* The totalPage to set. 9rS,?
*/ z<h|#@\
publicvoid setTotalPage(int totalPage){ y!hi"!
this.totalPage = totalPage; LuL$v+`
} q)k{W>O
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} > Y]_K
\HD-vINV;
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r&Qt_
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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 0ERsMnU'
sZwZWD'
个PageUtil,负责对Page对象进行构造: yKlU6t&`
G
java代码: *v&*% B
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/*Created on 2005-4-14*/ +`Fb_m)f
package org.flyware.util.page; P9s_2KOF
'e85s%ru
import org.apache.commons.logging.Log; Ck@M<(x
import org.apache.commons.logging.LogFactory; ^9=4iXd
om>VQ3
/** Ko+al {2
* @author Joa Q0WY$w1<
* x G ^f
*/ zQ<88E&&Xs
publicclass PageUtil { 7*MU2gb
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privatestaticfinal Log logger = LogFactory.getLog P=Puaz5&{
4i`S+`#
(PageUtil.class); (7L/eDMT
MX?}?"y
/** 5QOZ%9E&M
* Use the origin page to create a new page ]!J<,f7W
* @param page >3!DOv
* @param totalRecords LyV#j>gD
* @return *F|+2?a:$
*/ RAwk7F3qn
publicstatic Page createPage(Page page, int }k| g%HJ
sjb-Me?
totalRecords){ VfRs[3Q
return createPage(page.getEveryPage(), 3A d*,>!
D$$3fN.iEL
page.getCurrentPage(), totalRecords); PLdf_/]-
} .aJ%am/:%
7jT#BWt
/** :Fnzi0b
* the basic page utils not including exception BvQUn@ XE
*w|iu^G
handler P8IRH#ED
* @param everyPage F^]aC98]1
* @param currentPage -F1P28<?
* @param totalRecords 0$l&i=L
* @return page &1~Re.*B
*/ M/l95fp
publicstatic Page createPage(int everyPage, int hg4J2m
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currentPage, int totalRecords){ cCk1'D|X[e
everyPage = getEveryPage(everyPage); L\YZT|
K(
currentPage = getCurrentPage(currentPage); %UBPoq
int beginIndex = getBeginIndex(everyPage, O"8 P#Ed
wR(ttwxK3
currentPage); hwp/jO:7\
int totalPage = getTotalPage(everyPage, "h$D7 mL
xY+A]Up|w
totalRecords); /3s@6Ex}E
boolean hasNextPage = hasNextPage(currentPage, %;
qY'+
Txu>/1N,
totalPage); `BpCRKTG
boolean hasPrePage = hasPrePage(currentPage); RW)k_#%=
&*jixqzvn
returnnew Page(hasPrePage, hasNextPage, HwM/}-t
everyPage, totalPage, 0S_Ra+e
currentPage, K)Ge
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beginIndex); 3}yraX6r!
} "(N-h\7Ex9
D"'#one
privatestaticint getEveryPage(int everyPage){ CM"s9E8y
return everyPage == 0 ? 10 : everyPage; 1&} G+y
} ONNW.xHp
4 #G3ew
privatestaticint getCurrentPage(int currentPage){ [XxA.S)x3
return currentPage == 0 ? 1 : currentPage; *50ZinfoG
} 9a-]T=5Ee
S`4e@Z$
privatestaticint getBeginIndex(int everyPage, int F\:{}782u
u>1v~3,r#
currentPage){ (a,6a
return(currentPage - 1) * everyPage; 4@gl4&<h
} >|(WS.n 3C
nMeS CX
privatestaticint getTotalPage(int everyPage, int I ;l`VtD
>" i~ x
totalRecords){ ~;` fC|)
int totalPage = 0; :%pw`b, =V
[&fWF~D-p<
if(totalRecords % everyPage == 0) /1U,+g^O>
totalPage = totalRecords / everyPage; aQC7 V !v
else E|\3f(aF
totalPage = totalRecords / everyPage + 1 ; V`U/'N-ay
N#mK7|\c?:
return totalPage; dfnX!C~6 \
} ]D?oQ$q7
p<ry$=`
privatestaticboolean hasPrePage(int currentPage){ -B",&yTV
return currentPage == 1 ? false : true; XPrY`,kN
} Fv<]mu
N{|[R
privatestaticboolean hasNextPage(int currentPage, g\E ._ab<
f.sPE8#3=
int totalPage){ 0GF%~6
return currentPage == totalPage || totalPage == s8C:QC
sY&rbJ(P
0 ? false : true; Idt@Hk5<&
} zv>ZrFl*
Z5 w`-#
zp}yiE!bl
}
4{c`g$j>
oVAOGHE
A7mMgb_
!Mm+bWn=mB
V>DXV-%&C
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 9
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Uzy;#q
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 *vEU}SxRuv
xtG)^x!
做法如下: !x+MVJ]
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 `W6:=H
Be'?#Qe
的信息,和一个结果集List: ,!xz*o+#@
java代码: d91I
3XM Bu*
\;4L~_2$q
/*Created on 2005-6-13*/ -<u-
+CbuT
package com.adt.bo; Z1E`I89<
Q3'(f9
x
import java.util.List; q=(M!9cE
t"jIfU>'a/
import org.flyware.util.page.Page; EY=\C$3J:
y=y/d>=w
/** |E>v~qD8I
* @author Joa e-YGuWGN7
*/ |s)VjS4@
publicclass Result { R;5QD`
wR`w@5,d
private Page page; ZP]2/;h
g6tWU
private List content; f]O5V$!RuE
Te{aB"B
/** ^R&_}bp
* The default constructor E,"b*l.
*/ :..E:HdYO
public Result(){ ljaAB+
super(); UtHmM,*I
} 3Y.d&Nz
3 LZL!^ 5N
/** [M,27
* The constructor using fields )eIz{Mdp=
* eWqVh[
* @param page BVwRPt
* @param content HXlr
*/ 7M&.UzIY`
public Result(Page page, List content){ a,F8+
Pb>
this.page = page; 81%qM7v9H
this.content = content; )j)y5_m
} VyBJIzs0
fS8XuT
/** 8 RzF].)
* @return Returns the content. k}+MvGq
*/ HZ[68T[8b
publicList getContent(){ %Hh &u
.
return content; 9g<_JcN
} ,_e/a
J7&.>y1%
/** Q}k_#w
* @return Returns the page. 7k[`]:*o
*/ =]2RC1#}e
public Page getPage(){ MfZ}xu
return page; V@5 4k*V
} vh:UXE lm
pU'`9fLi_
/** ZipK;!9by
* @param content VLwJ6?.f'
* The content to set. ePu2t3E
*/ Y;%R/OyWY
public void setContent(List content){ PEwW*4Xo
this.content = content; l72ie
} T^-H_|/M
"=v J}
/** 4IGQ,RTB
* @param page p0:&7,+a,
* The page to set. M25z<Y
*/ o+6^|RP
publicvoid setPage(Page page){ A{n*NxKCX!
this.page = page; ~$TE
} 3ec==.
} Nsy9
h}+A
s/p>30Fg
)oz-<zW
'8kL1
KWZNu&)
2. 编写业务逻辑接口,并实现它(UserManager, 8t^;O!
+'YSpJ
UserManagerImpl) ZCOuv6V+
java代码: *|.yX%"k
q}7Df!<|
e4NX\tCpw
/*Created on 2005-7-15*/ {KQ-Ce-6
package com.adt.service; dM@k(9|
pN^G[
import net.sf.hibernate.HibernateException; aGzdur
VHXR)}
import org.flyware.util.page.Page; $4ZDT]n
#\!hBL
@b
import com.adt.bo.Result; $BO}D
EF7|%N
/** fAA@ziKg
* @author Joa ss M9t
*/ 3\U,Kg
publicinterface UserManager { ?U.&7yY
Bbe/w#Z
public Result listUser(Page page)throws X:} 5L>'
SJ|.% gn
HibernateException; 5IF~]5s
BX)cV
} W~@GK
M$-(4 0
~ @"Qm;}
"
gCBZA;/
Uc%`? +Q
java代码: }?ac<> u&
=*)O80oaW
P A+e= %
/*Created on 2005-7-15*/ Zv7$epDUz
package com.adt.service.impl; TYLl_nGr
T;pn -
import java.util.List; snk{u/0Xm
'/"M02a
import net.sf.hibernate.HibernateException; Qre&N_
tZ{q\+h
import org.flyware.util.page.Page; |(8Hk@\CT>
import org.flyware.util.page.PageUtil; $R#L@iL-
8@C|exAD`
import com.adt.bo.Result; gt~2Br4
import com.adt.dao.UserDAO; `LHfAXKN
import com.adt.exception.ObjectNotFoundException; 4sD:J-c
import com.adt.service.UserManager; +M%2m3.Jo
/
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/** #,9TJ:~N
* @author Joa Y
Z2VP
*/ j!8+|eAkk
publicclass UserManagerImpl implements UserManager { {,mRMDEy
v}*u[GWl]
private UserDAO userDAO; N)I
T?
PHL@1K{)
/** CzsY=DBH=
* @param userDAO The userDAO to set. >yHnz?bf@
*/ !?-5hh1\
publicvoid setUserDAO(UserDAO userDAO){ r#Oz0=0u
this.userDAO = userDAO; DO,&Foh\
} S/:QVs
e ~,'|~
C5
/* (non-Javadoc) s/&]gj"
* @see com.adt.service.UserManager#listUser &^D@(m7>{K
~E|V{z%
(org.flyware.util.page.Page) G78j$
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*/ %_=R&m'n`
public Result listUser(Page page)throws U=#ylQ
o 0
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HibernateException, ObjectNotFoundException { U$JIF/MO_
int totalRecords = userDAO.getUserCount(); WsDe0F
if(totalRecords == 0) >\x
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throw new ObjectNotFoundException ]SR`96vG
"^e?E:( 3
("userNotExist"); h}<ZZ
page = PageUtil.createPage(page, totalRecords); 5Cyjq0+
List users = userDAO.getUserByPage(page); t4c#' y
returnnew Result(page, users); imq(3?
} J#Ehx|
bvRGTOxO
} >"{zrwNq
7?WBzo!!L
w=>mG-
+rO<'H:umJ
4'[ V'c\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 uiEA=*axp
/<pQ!'/G
询,接下来编写UserDAO的代码: l5nDt$Ex
3. UserDAO 和 UserDAOImpl: 05LQh
java代码: [)0 k}
3NZFW{u
wupD
/*Created on 2005-7-15*/ 2 3w{h d
package com.adt.dao; cW^)$>A
Afl'-
import java.util.List; 17 iq
JJ3JULL2
import org.flyware.util.page.Page; MFsy`aiS
A+E@OO w*~
import net.sf.hibernate.HibernateException; Hu2g (!
.TS=[WGMS
/** :Rx"WY
* @author Joa la 7QN QW
*/ ]lYEJ`
publicinterface UserDAO extends BaseDAO { ",_
&V{,D))6[
publicList getUserByName(String name)throws ov>L-
BtApl)q#
HibernateException; eE_XwLE
7f,WzvV
publicint getUserCount()throws HibernateException;
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?G w89r
publicList getUserByPage(Page page)throws <&Xq`i/(
R*C+Yk)Tkt
HibernateException; Dx)XC?'xO
'Rw]
C[
} lc#zS_
*uM*)6O 3
bu9&sQ;
wcT6d?*5
0J</`/g H
java代码: '
uw&f;/E
$zi\ /Yw
SnU{ZGR>sP
/*Created on 2005-7-15*/ c)fp;^
package com.adt.dao.impl; 8{t&8Ql n
6^u(PzlA|~
import java.util.List; 5)<jPyC
(.+n1)L?
import org.flyware.util.page.Page; YcZ4y@6"
MX\-)e#
import net.sf.hibernate.HibernateException; W/Q%%)J
import net.sf.hibernate.Query; Ls*=mh~IY
2=+ ,jX{
import com.adt.dao.UserDAO; EIm\!'R]
R?SHXJ%'
/** _8`;Xgp
* @author Joa AE
_~DZ:%c
*/ y@JYkp>I
public class UserDAOImpl extends BaseDAOHibernateImpl XjU; oh4:.
1]`HX=cl
implements UserDAO { k@U`?7X
^SCWT\E
/* (non-Javadoc) )zV5KC{{
* @see com.adt.dao.UserDAO#getUserByName 9%6`ZS~3
X
jN.X
(java.lang.String) Q6>( Z
*/ Or>[_3
publicList getUserByName(String name)throws zxdO3I
Jl ?Q}SB
HibernateException { KL`>mJo$
String querySentence = "FROM user in class v}D!
tYa8I/HpT
com.adt.po.User WHERE user.name=:name"; 0MPDD%TP
Query query = getSession().createQuery 0yNlf-O
0n=E.qZ9c
(querySentence); Gzt5efygKt
query.setParameter("name", name); oFp&j@`k8j
return query.list(); JqZ5DjI:
} "Fiv
]^
[L^#<@S
/* (non-Javadoc) k({8C`&tK/
* @see com.adt.dao.UserDAO#getUserCount() &r%3)Z8Et
*/ UC@ "<$'C
publicint getUserCount()throws HibernateException { pC8i&_A
int count = 0; [NcOk,
String querySentence = "SELECT count(*) FROM ic#drpl,
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user in class com.adt.po.User"; i-b7
Query query = getSession().createQuery )`-]nMc
$)V4Eu;
(querySentence); -2_$zk*n
count = ((Integer)query.iterate().next zPYa@0I
&@-glF5
()).intValue(); K e8cfd~c
return count; $n"Llw&)
} L+L9)8FJ
V
""
/* (non-Javadoc) )`^:G3w
* @see com.adt.dao.UserDAO#getUserByPage {5JXg9um
C-Z,L#
(org.flyware.util.page.Page) }1dh/Cc`
*/ *93 N0m4Rl
publicList getUserByPage(Page page)throws i\G3
u#
_T$\$v$ {
HibernateException { T-TH.
R
String querySentence = "FROM user in class -C+vmY*@
tS7u#YMh
com.adt.po.User"; 3F1Z$d(
Query query = getSession().createQuery KK6YA
2Mda'T8
(querySentence); kn\>ZgU
query.setFirstResult(page.getBeginIndex()) Y')+/<Q2E
.setMaxResults(page.getEveryPage()); Zpmy)W]1
return query.list(); 7SCI_8`
} }0G Ab2
Xk$lQMwZ
} .w~USJ=X
)EoG@:[
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A-FwNo2"%
0"N %Vm
至此,一个完整的分页程序完成。前台的只需要调用 w6_}]
&F
L;[*F-+jD
userManager.listUser(page)即可得到一个Page对象和结果集对象 d,)L, J
d}Om?kn
的综合体,而传入的参数page对象则可以由前台传入,如果用 iJBZnU:Mp
O]>`B{
webwork,甚至可以直接在配置文件中指定。 C0RwW??t
%}[??R0
下面给出一个webwork调用示例: kXWx )v
java代码: $u :=lA:N
Gf?KpU
z0sB*5VH
/*Created on 2005-6-17*/ FQyiIT6
package com.adt.action.user; 6D],275`J
$m>e!P>%u
import java.util.List; v|GvN|_|
K^bn4Nr
import org.apache.commons.logging.Log; \w3wh*
import org.apache.commons.logging.LogFactory; ,n*.Yq
import org.flyware.util.page.Page; 5kF5`5+Vj
_*9Zp1r
import com.adt.bo.Result; d:D2[
import com.adt.service.UserService; <_![~n$H
import com.opensymphony.xwork.Action; ]^y}}y
m_B5M0},
/** Ogb_WO;)
* @author Joa 9O"?T7i"#
*/ A SSoKrFL
publicclass ListUser implementsAction{ C N"c
G\Me%{b#
privatestaticfinal Log logger = LogFactory.getLog S%@$J~\rx
IQDWH/c
(ListUser.class); |Xag:hof
Ut+m m\7
private UserService userService; bA)Xjq)Rr
^?2txLv,6
private Page page; [3.rG!Na
HIF]c
privateList users; fp7Qb $-A
[>-k(D5D
/* HZT;7<
* (non-Javadoc) $spf=t"nh
* =T$E
lXwJ
* @see com.opensymphony.xwork.Action#execute() g@Zc'g/XB
*/ (GQy"IuFh
publicString execute()throwsException{ ?vVkZsU
Result result = userService.listUser(page); ,"'agg:St
page = result.getPage(); 6]Jv3Re'(I
users = result.getContent(); Y'-Lt5SCS
return SUCCESS; O v-I2
} 4g 1h:I/
+FiV!nRkZ
/** n'ro5D
* @return Returns the page. =N=,;<6%A
*/ G<-.{Gx)
public Page getPage(){ Z8T{Xw6%
return page; 0pR04"`;
} 3
*G=U
SCjACQ}-
/** ctZW7
* @return Returns the users. ,'!&Z *
*/ `#R$
publicList getUsers(){ r#XDgZtI
return users; & zG=
} ;[xDc>&("Q
)"1D-Bc\Q
/** SBEJ@&iB~
* @param page BjH(E'K[b
* The page to set. ;cO0Y.V9l
*/ >eC^]#c
publicvoid setPage(Page page){ bfJDF(=h
this.page = page; _ReQQti[
} "K8qmggTq
0h7\zoZ5
/** 1)r1/0
* @param users ,y0kzwPR1
* The users to set. ;#;X@BhS
*/ gQ?k}D
publicvoid setUsers(List users){ y?rsfIth`
this.users = users; s#Le`pGoW
} Ev()2 80
%$cwbh-{{
/** 5`+*({
* @param userService 9J?j2!D
* The userService to set. 3] !(^N>V
*/ r[gV`khka
publicvoid setUserService(UserService userService){ +q4T];<
this.userService = userService; '.iUv#j4Sh
} EgY]U1{
} J^v_VZ3
?832#a?FZ;
}$7Hf+G
{*|yU"
mz#(\p=T
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, hE=cgO`QU
j#*K[
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 +?c&Gazi
zYep
V
么只需要: TqlUe@E
java代码: +@!9&5SA
X)yTx8v4
lu >>~vy6
<?xml version="1.0"?> nhIITfJJ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork aA:Ky&5e
lyib+Sa ?`
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ss[8d%V
%PG0PH4?
1.0.dtd"> Dk4Wj"LS
S"Efp/-
<xwork> Ad"::&&Wk
ZQyT$l~b
<package name="user" extends="webwork- R ~cc]kp0
3*FktXmI}
interceptors"> 1D*eu
, vky
<!-- The default interceptor stack name P$!Ht
Tv(s?T6f
-->
W6a2I
<default-interceptor-ref >Mn"k\j4
b~\![HoCMM
name="myDefaultWebStack"/> _rajm J
o?b"B+#
<action name="listUser" N8KHNTb-M
a#kZY7s
class="com.adt.action.user.ListUser"> K,So#Ui
<param @ O%m,
xOkf9k_
name="page.everyPage">10</param> E&97;VH
<result !Zs;m`j&9
s#d>yx_b
name="success">/user/user_list.jsp</result> \ ,?yj
</action> o77HRX
'-
Z4GcL
</package> 9J>DLvl;
+oyc9PoXF
</xwork> &AoWT:Ea
TzIgEn~
$mpfr#!&3o
Jb0]!*tV
02S Uyv(Mt
]qXfgc
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 @]cpPW-b
V,>#!zUv
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 /
{A]('t
BkIvoW_
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 "Uyw7
p<jHUG4?'
:}E*u^v K
'2%hc\P6P
_/KW5
我写的一个用于分页的类,用了泛型了,hoho vK6bpzI
3
6z/8nf +u
java代码: (US8Sc
1Og9VG1^
6R?J.&|
package com.intokr.util; zis-}K<
!D z:6r
import java.util.List; F2XXvxG
iA%3cpIc(Z
/** -,Q<*)q{
* 用于分页的类<br> YpuA,r;"
* 可以用于传递查询的结果也可以用于传送查询的参数<br> n:7=z0
s
* 3lKIEPf6r
* @version 0.01 ~)()PO
* @author cheng )hn,rmn
(P
*/ ,@<-h* m
public class Paginator<E> { )`g[k"yB3
privateint count = 0; // 总记录数 d` ^@/1tO
privateint p = 1; // 页编号 smWA~Aq
privateint num = 20; // 每页的记录数 Ir]b.6B
privateList<E> results = null; // 结果 Y \j &84
/0(4wZe~?
/** XbHcd8N T
* 结果总数 Bw{W-&$o
*/ &qo'ge8p
publicint getCount(){ EkJo.'0@
return count; V,2O`D%
} }}ogdq
*aTM3k)Zs
publicvoid setCount(int count){ >+8mq]8^
this.count = count; Q>X ;7nt0
} Phx/9Kk
a8dR.
/** ."3 J;j
* 本结果所在的页码,从1开始 5|AZ/!rb
* Ju:=-5r"'
* @return Returns the pageNo. dAga(<K
*/ 89WuxCFS
publicint getP(){ jkfI,T
return p; 2wu
5`Z[E
} m@jOIt!<
+L_.XToq-
/** r"rEVx#1=
* if(p<=0) p=1 L !{^^7
* 5ptbz<Xv
* @param p $'e.bh
*/ QO|ODW+D
publicvoid setP(int p){ <01MXT-
if(p <= 0) az`5{hK
p = 1; 15 SIZ:Q
this.p = p; CIV6Qe"<
} K5k,47"
ukri7 n*
/** @89mj{
* 每页记录数量 &\1Dy}:
*/ M?]ObIM:5
publicint getNum(){ }
1c5#Ym
return num; C?b Mj[$
} !(+?\+U lE
e_,_:|t
/** L9G=+T9
* if(num<1) num=1 V1(eebi|
*/ NbgP,-
publicvoid setNum(int num){ i3f/{D/
if(num < 1) 6g$+ ))g
num = 1; ,m0=zH4+:
this.num = num; {!x-kF_
} v^KJU
+
kV-a'"W5
/** :@Q_oyWE8
* 获得总页数 .]8 Jeb
*/ 5*ABw6'6
publicint getPageNum(){ n cihc$V<
return(count - 1) / num + 1; >o(*jZ
} CuDU~)`
SR8[
7MU
/** F[9IHT6{
* 获得本页的开始编号,为 (p-1)*num+1 SU x\qz)
*/ *6k
(xL
publicint getStart(){ viKN:n! Ev
return(p - 1) * num + 1; =L&_6