Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 y`j_]qvt
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Ct'tUF<K5
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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 &vmk!wAs
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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 WdOxwsq"
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分页支持类: hwM<0Jf
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java代码: c!HGiqp
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package com.javaeye.common.util; oU)(/
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import java.util.List; N/F_,>E
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publicclass PaginationSupport { v9H
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publicfinalstaticint PAGESIZE = 30; R'Ue>k
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privateint pageSize = PAGESIZE; }-:B`:K&
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privateList items; D`QMlRzXy
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privateint totalCount; #jBmWaP.
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privateint[] indexes = newint[0]; 2@bOy~$A
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privateint startIndex = 0; \j!/l
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public PaginationSupport(List items, int (_#E17U)_
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totalCount){ &PXT$x[i
setPageSize(PAGESIZE); {*bx8*y1
setTotalCount(totalCount); p[&Jl
setItems(items); S8qg"YR
setStartIndex(0); +E9G"Z65iP
} D)G oWt
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public PaginationSupport(List items, int 9Avj\G
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totalCount, int startIndex){ (!@gm)#h
setPageSize(PAGESIZE); ^}2!fRKAmo
setTotalCount(totalCount); T7i>aM$+
setItems(items); "3jTU
setStartIndex(startIndex); Ngx2N<$<*g
} qy?$t:*pp
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public PaginationSupport(List items, int rbOJ;CK
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totalCount, int pageSize, int startIndex){ zU[o_[+7^
setPageSize(pageSize); dlyGgaV*X
setTotalCount(totalCount); kT
setItems(items); rZ,3:x-:
setStartIndex(startIndex); Uy=yA
} >7@,,~3
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publicList getItems(){ ta.Lq8/
return items; CSjd&G*ZB
} 3_G0eIE"u
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publicvoid setItems(List items){ 5Kd"W,
this.items = items; t0cS.hi
} sh,4n{+
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publicint getPageSize(){ W 8`6O2
return pageSize; 6{d?3Jk
} >4bw4
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publicvoid setPageSize(int pageSize){ 7`~0j6FY
this.pageSize = pageSize; _LgP
} v@G&";|
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publicint getTotalCount(){ /)v+|%U
return totalCount;
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} msw'n
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publicvoid setTotalCount(int totalCount){ >l-u{([B
if(totalCount > 0){ IA}vN3
this.totalCount = totalCount; uN?Lz1W\;
int count = totalCount / @rqmDpU
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pageSize; }x$@j
if(totalCount % pageSize > 0) i+QVs_jW
count++; 'N6oXE
indexes = newint[count]; nGTGX
for(int i = 0; i < count; i++){ Ax|'uvVAPT
indexes = pageSize * I`xC0ZUKj
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} BbFLT@W4
}else{ RpU i'
this.totalCount = 0; C3.]dsv:
} p4O[X\T
} \+Qd=,!i(
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publicint[] getIndexes(){ |H8C4^1Rq
return indexes; [V
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} )6"p@1\u
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publicvoid setIndexes(int[] indexes){ }'{"P#e8"q
this.indexes = indexes; X9c<g;
} 731RqUR
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publicint getStartIndex(){ bCTN^
return startIndex; 3P75:v
} X:f5t` ;
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publicvoid setStartIndex(int startIndex){ (-1{W^(
if(totalCount <= 0) Mx0~^l
this.startIndex = 0; \ eba9i^
elseif(startIndex >= totalCount) vnf2Z,f%
this.startIndex = indexes w"D1mI!L
7
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[indexes.length - 1]; Ymnh%wS
elseif(startIndex < 0) Qru&lAYc<
this.startIndex = 0; 3XUVUd~
else{ ?FS0zc!+
this.startIndex = indexes ]ZR`
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[startIndex / pageSize]; * >2FcoN;
} LB.B w
} p4\sKF8-
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publicint getNextIndex(){ uDcs2^2l
int nextIndex = getStartIndex() + 9;n*u9<
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pageSize; E!WlQr:b$
if(nextIndex >= totalCount) "7fEL:|j
return getStartIndex(); sm?b,T/
else M4;M.zxJv
return nextIndex; F;/^5T3wI
} X16O9qsh
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publicint getPreviousIndex(){ s7jNRY V
int previousIndex = getStartIndex() - fhdqes])
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pageSize; %#EzZD
if(previousIndex < 0) [#X}(
return0; E>E^t=;[
else 2!9W:I7
return previousIndex; y%
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} $zhvI*0
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} ut]&3f''
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抽象业务类 Bn.R,B0PL
java代码: SY.koW
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/** ]m&Ss
* Created on 2005-7-12 ?|`n&HrP
*/ Az(,Q$"|5
package com.javaeye.common.business; gDw(_KC
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import java.io.Serializable; U0|bKU
import java.util.List; #PC*l\
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import org.hibernate.Criteria; "9X(.v0ze
import org.hibernate.HibernateException; Jv%)UR.]
import org.hibernate.Session; [EVyCIcY,h
import org.hibernate.criterion.DetachedCriteria;
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import org.hibernate.criterion.Projections; S,,Wb&A$
import J?E!\V&U
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org.springframework.orm.hibernate3.HibernateCallback; F}F{/
import ",5=LW&,
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org.springframework.orm.hibernate3.support.HibernateDaoS 4__HH~j ?Q
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upport; 'UGgY3
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import com.javaeye.common.util.PaginationSupport; cYOcl-*af
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public abstract class AbstractManager extends N!tNRMTi
{~#01p5
HibernateDaoSupport { )Fqtb;W=
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privateboolean cacheQueries = false; 6/'X$}X
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privateString queryCacheRegion; juu"V]Q1
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publicvoid setCacheQueries(boolean \O~WMN
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cacheQueries){ fI.X5c>WK
this.cacheQueries = cacheQueries; a>y e
} ^4[QX
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publicvoid setQueryCacheRegion(String 2]x,joB
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queryCacheRegion){ Q/HEWk
this.queryCacheRegion = Fy>g*3
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queryCacheRegion; 'Vhnio;qC
} nkN2Bqt$
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publicvoid save(finalObject entity){ wk=s3^
getHibernateTemplate().save(entity); ne[H `7c
} }\A0g}
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publicvoid persist(finalObject entity){ b+dmJ]c
getHibernateTemplate().save(entity); HR
} ?H{?jJj$H
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publicvoid update(finalObject entity){ gxVJH'[V5
getHibernateTemplate().update(entity); e9CvdR
} wSALK)T1{
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publicvoid delete(finalObject entity){ K|;L{[[yH
getHibernateTemplate().delete(entity); AO7X-,
} 7 lq$PsC
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publicObject load(finalClass entity, ?Qpi(Czbpq
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finalSerializable id){ G he@m6|D
return getHibernateTemplate().load \pI
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(entity, id); )%:
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} G+3uY25y
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publicObject get(finalClass entity, ZS&lXgo
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finalSerializable id){ Z#GR)jb+
return getHibernateTemplate().get \x_$Pu
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(entity, id);
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} B]>rcjD
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publicList findAll(finalClass entity){ nF
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return getHibernateTemplate().find("from :mdoGb$dr
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" + entity.getName()); H_l>L9/\
} E_xk8X~
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publicList findByNamedQuery(finalString |A H@W#7j
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namedQuery){ Gl T/JZ9
return getHibernateTemplate XpT})AV
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().findByNamedQuery(namedQuery); hg `N`O
} kPnuU!
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publicList findByNamedQuery(finalString query, 6x@]b>W
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finalObject parameter){ s%N6^}N
return getHibernateTemplate z2dW)_fU$
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().findByNamedQuery(query, parameter); _`9WNJiL
} uVw|jj
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publicList findByNamedQuery(finalString query, <FvljKuq+
*MN("<A_
finalObject[] parameters){ t\ 9Y)d
return getHibernateTemplate }sfvzw_
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().findByNamedQuery(query, parameters); XfwH1n/o#
} A+hT2Ew@t}
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publicList find(finalString query){ \@7 4I7
return getHibernateTemplate().find &KeD{M%
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(query); g^k=z:n3,
} i32S(3se
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publicList find(finalString query, finalObject CyJZip
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parameter){ R9Y{kk0M
return getHibernateTemplate().find /5:qS\Zl
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(query, parameter); 35SL*zS@-
} z|N*Gs>,
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public PaginationSupport findPageByCriteria uU8L 93
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(final DetachedCriteria detachedCriteria){ `$r?^|T
return findPageByCriteria PW-sF
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); fR lJ`\ t
} v/G^yZa
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public PaginationSupport findPageByCriteria *18J$
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(final DetachedCriteria detachedCriteria, finalint mp0!S
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startIndex){ Now2ad&
return findPageByCriteria I]N!cEr;@-
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(detachedCriteria, PaginationSupport.PAGESIZE, pR~"p#Y
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startIndex); %VgK::)r
} d#HN'(2t
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public PaginationSupport findPageByCriteria ;:ocU?
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(final DetachedCriteria detachedCriteria, finalint NJ!}(=1|K
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pageSize, toC|vn&P
finalint startIndex){ $b"Ex>
return(PaginationSupport) 8"x\kSMb
h,2?+}Fn
getHibernateTemplate().execute(new HibernateCallback(){ 1.z !u%2
publicObject doInHibernate wW'.bqA
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(Session session)throws HibernateException { [N*`3UZk"
Criteria criteria = ~fly6j|u
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detachedCriteria.getExecutableCriteria(session); q62U+o9G
int totalCount = 9B1bq #
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((Integer) criteria.setProjection(Projections.rowCount @S Quc
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()).uniqueResult()).intValue(); \'Ca%j
criteria.setProjection R&1xZFj
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(null); *(Us:*$W.
List items = U,^jN|v
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criteria.setFirstResult(startIndex).setMaxResults is=|rY9$
)yv~wi
(pageSize).list(); >4AwjS}H
PaginationSupport ps = coc:$Sr%
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new PaginationSupport(items, totalCount, pageSize,
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startIndex); 0,[-4m
return ps; ${, !L l7)
} m:5bb3
}, true); 4fdO Ow
} x9H
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public List findAllByCriteria(final uWerC?da
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DetachedCriteria detachedCriteria){ bn"z&g
return(List) getHibernateTemplate ~1.~4~um
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().execute(new HibernateCallback(){ <x1H:8A
publicObject doInHibernate $*dY f
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(Session session)throws HibernateException { m_>~e}2'A
Criteria criteria = T
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detachedCriteria.getExecutableCriteria(session); k.w}}78N2N
return criteria.list(); m?Dk(DJ
} Xw9"wAj
}, true); 97SG;,6
} !fG`xZ~
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public int getCountByCriteria(final ogKd}qTov
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DetachedCriteria detachedCriteria){ KXga{]G:
Integer count = (Integer) =?-
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getHibernateTemplate().execute(new HibernateCallback(){ Jl^THoEL
publicObject doInHibernate JB\BP$ap
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(Session session)throws HibernateException { FuZLE%gP
Criteria criteria = gT4H?
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=)y=39&;/
detachedCriteria.getExecutableCriteria(session); z`+j]NX]
return jp QmKX
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criteria.setProjection(Projections.rowCount AZjj71UE
||sj*K
()).uniqueResult(); p9$=."5
} &T/}|3S
}, true); HA%r:Px
return count.intValue(); nXF|AeAco
} z6Jfu:_N!
} b'~IFNt*^
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用户在web层构造查询条件detachedCriteria,和可选的 SB` "%6
" ^:$7~%bA
startIndex,调用业务bean的相应findByCriteria方法,返回一个 |MXv
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4 jeUYkJUM
PaginationSupport的实例ps。 auT$-Ki8
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ps.getItems()得到已分页好的结果集 6J%+pt[tu
ps.getIndexes()得到分页索引的数组 N8:&v
ps.getTotalCount()得到总结果数 iVGc\6+'
ps.getStartIndex()当前分页索引 *Ad7GG1/u
ps.getNextIndex()下一页索引 yS:1F
PA$_
ps.getPreviousIndex()上一页索引 2Md'<.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 [,fd Nxc8
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Bswd20(w
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一下代码重构了。 \dag~b<
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我把原本我的做法也提供出来供大家讨论吧: z~BrKdS
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3
首先,为了实现分页查询,我封装了一个Page类: 2<@27C5
java代码: s GP}>w-JZ
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/*Created on 2005-4-14*/ B:\TvWbu
package org.flyware.util.page; /8` S}g+
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/** !*gTC1bvB
* @author Joa 21BlLz
*
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*/ ^L<*ggw
publicclass Page { 6uijxia
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/** imply if the page has previous page */ txwTJScg
privateboolean hasPrePage; AQ 5CrYb
lAwOp
/** imply if the page has next page */ e[@q{.
privateboolean hasNextPage; mTzzF9n"Y
~=,|dGAa$
/** the number of every page */ ,1YnWy*
privateint everyPage; #)BdN
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/** the total page number */ Tx7YHE6{
privateint totalPage; t*)-p:29h
1+^L,-k!
/** the number of current page */ Xx0}KJq~"
privateint currentPage; _;BN;].
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/** the begin index of the records by the current Ek ,s6B)'d
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query */ hsQrHs'k
privateint beginIndex; ?eb2T`\0Q
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/** The default constructor */ u= K?K
public Page(){ snBC +`-
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} w%1B_PyDg
*s6MF{Ds
/** construct the page by everyPage pAV}hB
* @param everyPage T@]vjXd![
* */ (r^IW{IndX
public Page(int everyPage){ /y,~?
this.everyPage = everyPage; g'`J'6Pn
} x=qACoq
jBEt!Azur
/** The whole constructor */ XRI1/2YA
public Page(boolean hasPrePage, boolean hasNextPage, kl| KFdA;
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int everyPage, int totalPage, `oh'rm3'8
int currentPage, int beginIndex){ -NVk>ENL4
this.hasPrePage = hasPrePage; T!hU37g h?
this.hasNextPage = hasNextPage; 2f]9I1{
this.everyPage = everyPage; 2I'\o7Y
this.totalPage = totalPage; O329Bkg
this.currentPage = currentPage; 4.3Bz1p
this.beginIndex = beginIndex; 'sm+3d
} VPf*>ph=
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/** @Ns^?#u~
* @return m4nJ9<-
* Returns the beginIndex. xnu|?;.}!
*/ +MQf2|--
publicint getBeginIndex(){ A;h0BQm/j
return beginIndex; I ,AI$A
} UJ)\E
^Hp
t9PS5O ;
/** ?#\?&uFJ}
* @param beginIndex SF;;4og
* The beginIndex to set. 8jjJ/Mz`
*/ -{ZTp8P>
publicvoid setBeginIndex(int beginIndex){ r&\}E+
this.beginIndex = beginIndex; +gOCl*L
} *kxk@(lT?
6yF4%Sz9
/** "_C^Bc
* @return =?57*=]0M
* Returns the currentPage. >;QkV6i7
*/ =5LtEgHU
publicint getCurrentPage(){ ;P _`4w3
return currentPage; F#iLMO&Q
} 8@/]ki`>
v^[Ny0cM
/** ,KIa+&vJW@
* @param currentPage `2NL'O:
* The currentPage to set. 8\y%J!b
*/ gzP(LfI5
publicvoid setCurrentPage(int currentPage){ N`grr{*_
this.currentPage = currentPage; g=[ F W@z
} qrNW\ME
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/** {:Z# 8dGe
* @return S]1+tj
* Returns the everyPage. [8SW0wsk
*/ cCU'~
publicint getEveryPage(){ OR( )D~:n
return everyPage; }<&g1x'pa
} Qkk~{OuC
4%p5X8|\ih
/** _?@>S 7-
* @param everyPage &.o}(e:]
* The everyPage to set. ~@bCSOIy
*/ ?i(Tc!
publicvoid setEveryPage(int everyPage){ CQ"IL;y
this.everyPage = everyPage; GwwxSB&y
} 4I^6[{_
*D,+v!wG9
/** _ZD)#?
* @return rem&F'x0V
* Returns the hasNextPage. *u7C){)gr[
*/ !V@Y \M
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publicboolean getHasNextPage(){ v<tH 3I+
return hasNextPage; \9i.dF
} klUxt?-
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/** q&Q* gEFK
* @param hasNextPage n4k.tq
* The hasNextPage to set. 8o4<F%ot
*/ F!`.y7hY@
publicvoid setHasNextPage(boolean hasNextPage){ g=b[V
this.hasNextPage = hasNextPage; $|6Le;
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} cdP+X'Y4D
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/** Si*Pi
* @return GMgsM6.R
* Returns the hasPrePage. d)r=W@tF]
*/ \D, 0
publicboolean getHasPrePage(){ ,`/!0Wmt
return hasPrePage; U`<EpO{j|
} G~a/g6M4
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/** 5&2=;?EO
* @param hasPrePage `W?aq]4x5
* The hasPrePage to set. '/;#{("
*/ *-_` xe
publicvoid setHasPrePage(boolean hasPrePage){ Ax0u \(p<^
this.hasPrePage = hasPrePage; #B`"B
} ?*,N
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q'+XTal
/** vxr3|2`
* @return Returns the totalPage. k%NY,(:(
* }%$9nq3
*/ IOTHk+w
publicint getTotalPage(){ *qY`MW
return totalPage; N##3k-0Ao
} $hndb+6q
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n
/** XV %L6x
* @param totalPage *[W! ng
* The totalPage to set. bMkn(_H)\
*/ +*)B;)P
publicvoid setTotalPage(int totalPage){ )V)4N[?GC
this.totalPage = totalPage; (sJ{27b_
} _rs!6tp
mN3%;$ND7
} $L:g7?)k
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 3{d1Jk/S
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个PageUtil,负责对Page对象进行构造: fRaVY`|wK
java代码: Jev@IORN\
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/*Created on 2005-4-14*/ "M_X9n_
package org.flyware.util.page; ~O@V;y
nm %ka4
import org.apache.commons.logging.Log; Rc?wIL)
import org.apache.commons.logging.LogFactory; G*ym[
RF g$N@g,
/** nN@8vivP%
* @author Joa zMtK_ccQ
* jh\q2E~,`
*/ HX+'{zm]
publicclass PageUtil { SRM[IU
<po(7XB
privatestaticfinal Log logger = LogFactory.getLog YaSwn3i/@S
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(PageUtil.class); 8"8sI
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/** 1K^/@^
* Use the origin page to create a new page ^x4,}'(
* @param page ,W{Qv<oo
* @param totalRecords x3wyIio*
* @return SGNi~o
*/ Cd|V<BB9
publicstatic Page createPage(Page page, int v{?9PRf\s
z?j~ 2K<4
totalRecords){ I|Z5*iXqCm
return createPage(page.getEveryPage(), fB
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page.getCurrentPage(), totalRecords); 5IdmKP|
} nV:.-JR
3e I:$1"Q
/** /MQd [03]
* the basic page utils not including exception 2$[u&__E
{hg,F?p
'
handler CmJ*oXyi
* @param everyPage hs<7(+a
* @param currentPage PcUi+[s;x
* @param totalRecords Fo?2nQ<
* @return page [uAfE3
*/ a}jaxGy
publicstatic Page createPage(int everyPage, int tJHzhH)
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currentPage, int totalRecords){ <-}6X
everyPage = getEveryPage(everyPage); wQM(Lm#Q
currentPage = getCurrentPage(currentPage); C+y:<oo)
int beginIndex = getBeginIndex(everyPage, y3;G<9K2c]
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currentPage); &)xoR4!2
int totalPage = getTotalPage(everyPage, bmt2~!
ub,Sj{Mq"
totalRecords); wG^{Jf&@$
boolean hasNextPage = hasNextPage(currentPage, 5"XcVH4g
oh& PQ{
totalPage); IWm|6@y
boolean hasPrePage = hasPrePage(currentPage); aeH
9:GQ6
7|,5;
returnnew Page(hasPrePage, hasNextPage, InPq1AH
everyPage, totalPage, ;"joebZ/
currentPage, E@t~juF!
+(cs,?`\
beginIndex); TmzEZ<} &7
}
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privatestaticint getEveryPage(int everyPage){ 9-bDgzk
return everyPage == 0 ? 10 : everyPage; #<v3G)|aS
} RMLs(?e
DJrA@hm/Y
privatestaticint getCurrentPage(int currentPage){ s'} oVx]
return currentPage == 0 ? 1 : currentPage; gtCd#t'(V
} q7m-} mBN~
!y4o^Su[
privatestaticint getBeginIndex(int everyPage, int "'6KQnpZ
U&`M G1uHe
currentPage){ lg1?g)lv
return(currentPage - 1) * everyPage; F5+f?B~?R?
} v
C><N
lv$tp,+
privatestaticint getTotalPage(int everyPage, int G+\2Aj
:j?Lil%R
totalRecords){ HlI*an
int totalPage = 0; c1MALgK~}\
q'c'rN^
if(totalRecords % everyPage == 0) pmQ9iA@=
totalPage = totalRecords / everyPage; Q3z-v&^E9
else \!G&:<h
totalPage = totalRecords / everyPage + 1 ; Zf?>:P
u^iK?S#Ci8
return totalPage; "MK:y[+*
} E >SnH
3&3S*1b-H
privatestaticboolean hasPrePage(int currentPage){ `;QpPSw +
return currentPage == 1 ? false : true; |3"'>*
J
} BhdJ/C^
FeSe^ ^dW
privatestaticboolean hasNextPage(int currentPage, M@s2T|bQw
L
F Z
int totalPage){ +XFF@h&=t
return currentPage == totalPage || totalPage == &IOChQ`8P
Z4E:Z}~''
0 ? false : true; _?O'65
} DFR.F:O%
a{Tv#P*!
WBTX~%*U
} `sJkOEc`
?L{[84GSO
hQ8/-#LO_
f5d"H6%L
tR0o6s@v/<
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 S
G]e^%i
qBKIl=
ne
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ETjlq]@j
vxZz9+UbF
做法如下: 2hmV1gj
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 "{L%5:H@
AP/5,M<
的信息,和一个结果集List: }2V|B4
java代码: 3x'BMAA+
*Swb40L^
b/5;377_
/*Created on 2005-6-13*/ /-G;#Wm
package com.adt.bo; ~G5)ya-
p# O%<S@?
import java.util.List; H4^-M Sw
X^fMt]
import org.flyware.util.page.Page; }MXZ
yv4hH4Io
/** ldi'@^
* @author Joa y=5s~7]
*/ x1Z?x,-D"
publicclass Result { wdl6dLu
7P=1+2V
private Page page; i<)c4
N`8?bU7a}"
private List content; m{gt(n
&[qLl
/** Uhb6{'+
* The default constructor A&F@+X6@
*/ +anNpy
public Result(){ &7|=8Z[o
super(); sT'wps 2
} 1&Nk
4vp,izNW
/** f>-OwL($P
* The constructor using fields 73 D|gF*
* QjF.U8
* @param page OHM.xw*?.
* @param content F}2U8O
*/ 5NBc8h7 V
public Result(Page page, List content){ Fu{[5uv
this.page = page; { S4?L8
this.content = content; r?[PIf
} '1^\^)&q
Y
-o*d@
/** x_bS-B)%Y:
* @return Returns the content. D3(|bSca
*/ JU/K\S2%,
publicList getContent(){ $PHKI B(
return content; Y@_ i32,r
}
4\dc
K(Zd-U
/** 8O("o7~"
* @return Returns the page. HQ ^> ~
*/ }4
P@`>e/`
public Page getPage(){ &6r".\;^
return page; H_vOZ0
} p\b:uy6#
"xdXHuX
/** >77
/e@
* @param content }g5h"N\$o
* The content to set. DJ[U^dWRn
*/ [$OD+@~A2
public void setContent(List content){ 2,E&}a|;b
this.content = content; Pm%ZzU
} h,rGa\X~0
kIP~XV~
/** Uj1^?d+b
* @param page dB^J}_wp
* The page to set. W^60BZ
*/ n"(n*Hf7b
publicvoid setPage(Page page){ k "'q
this.page = page; dxUq5`#G,
} !gW$A-XD
} pj?+cy
v~
3yZtyXRPn
(ZT*EFhb(
ol:,02E&
P\*-n"
2. 编写业务逻辑接口,并实现它(UserManager, ?dC[VYC\^
oT5?*3f
UserManagerImpl) CZxQz
java代码: J0C<Qb[
}\OLBg/
+mMn1&
/*Created on 2005-7-15*/ e7>)Z
package com.adt.service; ()}O|JL:K
xJJlV P
import net.sf.hibernate.HibernateException; y? )v-YGu
mQ('X~l
import org.flyware.util.page.Page; t`Mm
TB*g$*
import com.adt.bo.Result; 1CFrV=d
toX4kmC
/** 4/~8zvz&3
* @author Joa LV4x9?&
*/ rm1R^n
publicinterface UserManager { B`T|M$Ug
t A\N$
public Result listUser(Page page)throws k2j:s}RHY
q !EJs:AS
HibernateException; t \Fc <
nxA]EFS
} FOM~Uj
PF1!aAvVb
Kg~<h B6
rcF;Lp :
3k5Mty
java代码: j K$4G.x
HI,1~Jw+
<E&1HeP
/*Created on 2005-7-15*/ Iwize,J~X
package com.adt.service.impl; h"
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j/#kO?
import java.util.List; NA]7qb%%<
1LJ
?Ka[_*
import net.sf.hibernate.HibernateException; V4l`Alr\L
[WRs1$5
import org.flyware.util.page.Page; ryW1OV6?_0
import org.flyware.util.page.PageUtil; V%<<Udu<
bqsb (C
import com.adt.bo.Result; ^ Gq2"rDM
import com.adt.dao.UserDAO; jtS+y)2
import com.adt.exception.ObjectNotFoundException; gD@ &/j7
import com.adt.service.UserManager; q4xB`G
67<zBw2
/** 4)]g=-3
* @author Joa Olj]A]v}
*/ n&r-
publicclass UserManagerImpl implements UserManager { TEh]-x`
LCyci1\@
private UserDAO userDAO; -l`@pklQ
6IctW5b
/** QKwWX_3%Z]
* @param userDAO The userDAO to set. J=
ia
*/ x
+q"%9.c
publicvoid setUserDAO(UserDAO userDAO){ ~V`D@-VND
this.userDAO = userDAO; A AH-Dj|&l
} HvKueTQ
p<Ah50!B
/* (non-Javadoc) p27A#Uu2}
* @see com.adt.service.UserManager#listUser i74^J +xk
wTf0O@``6H
(org.flyware.util.page.Page) UacN'Rat
*/ nxsQDw\hy
public Result listUser(Page page)throws 3+EJ%
f8#WT$Ewy
HibernateException, ObjectNotFoundException { YRG+I GX
int totalRecords = userDAO.getUserCount(); ::j'+_9
if(totalRecords == 0) xv$^%(Ujp
throw new ObjectNotFoundException >QE^KtZ
95T%n{rz
("userNotExist"); pnxjuDN7}x
page = PageUtil.createPage(page, totalRecords); YQ,IdWav
List users = userDAO.getUserByPage(page); p0qQ(
returnnew Result(page, users); L}XEROTR
} "<v_fF<Y
$a15
8
} 6x]|IWvW
q)G*"
KjZ^\lq'
_xl#1>G^J
[l-zU}u&v
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,^26.p$
6lT1X)
询,接下来编写UserDAO的代码: yx{Ac|<mR
3. UserDAO 和 UserDAOImpl: UciWrwE
java代码:
CV]PCq!
`DG6ollp{
8kW9.
/*Created on 2005-7-15*/ D8m?`^Zz
package com.adt.dao; smIZ:L%
"sAR<5b
import java.util.List; ZNOoyWYi5
pr;<n\Y{
import org.flyware.util.page.Page; 6ynQCD
xXA$16kd
import net.sf.hibernate.HibernateException; g~FB&U4c
Yo|
H`m,
/**
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* @author Joa u8+<uWB
*/ iUS379wM}
publicinterface UserDAO extends BaseDAO { E0xUEAO
$rFv(Qc^=
publicList getUserByName(String name)throws 9'8OGCN
.7ahz8v
HibernateException; u+I-!3J87
{@Diig
publicint getUserCount()throws HibernateException; :]y;t/
,=$yvZs4[]
publicList getUserByPage(Page page)throws _\@i&3hkx
d2.n^Q"?3
HibernateException; "{z9 L+
]DmqhK`
} Qbl6~>T
W.MJyem
45kMIh~~X
R3?~+y&
Vq9hAD|k
java代码: o&(%:|
mKe{y.
Ic#+*W\ZW
/*Created on 2005-7-15*/ /rvXCA)j
package com.adt.dao.impl; ]3d&S5zU
a Q`a>&R0
import java.util.List; mNb+V /*x3
;Ic3th%u
import org.flyware.util.page.Page; U?$v1 ||
MYN1zYT6j
import net.sf.hibernate.HibernateException; `(Q58wR}
import net.sf.hibernate.Query; YQQ!1hw
7MoO2
import com.adt.dao.UserDAO; +QldZba
{H])Fob
/**
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* @author Joa pM(y?zGt
*/ g:[&]o} :9
public class UserDAOImpl extends BaseDAOHibernateImpl 6Otv[8^}
7DOAG[gH
implements UserDAO { Z:T4Z}4N
,l0s(Cg
/* (non-Javadoc) GExG1n-
* @see com.adt.dao.UserDAO#getUserByName ,P auP~L
NA/+bgyuT>
(java.lang.String) {F@;45)o
*/ |I OTW=>
publicList getUserByName(String name)throws Rx`0VQ
^1*p]j(
HibernateException { V{d"cs>9
String querySentence = "FROM user in class ~-W.yg6D{
m.V mS7_I
com.adt.po.User WHERE user.name=:name"; 5.GBd_;
Query query = getSession().createQuery "hy#L
0\t
"H G:by
(querySentence); e}K;5o=I
query.setParameter("name", name); L"}@>&6
return query.list(); wV5<sH__
} kY_UY~E
qZ1fQN1yG
/* (non-Javadoc) 0
?2#SM
* @see com.adt.dao.UserDAO#getUserCount() j<l>+.,
U
*/ E> 4
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publicint getUserCount()throws HibernateException { NoKYHN^*w
int count = 0; i^QcW!X&
String querySentence = "SELECT count(*) FROM =A!I-@]q<
57[O)5u.+
user in class com.adt.po.User"; .Bi7~*N
Query query = getSession().createQuery (>;~((2
\H" (*["&
(querySentence); |#-Oz#Eg'
count = ((Integer)query.iterate().next UI!EIZ*~
G53!wIW2:
()).intValue(); NEGpf[$
return count; pn
=S%Qf]
} pAa{,,Qc
\{UiGCK
/* (non-Javadoc) QkF-}P%
* @see com.adt.dao.UserDAO#getUserByPage eGguq~s`
JT_#>',
(org.flyware.util.page.Page) P AKh v.7
*/ O]~p)E
publicList getUserByPage(Page page)throws x`o_&09;CG
hOwVm;:
HibernateException { SnXYq7`t
String querySentence = "FROM user in class F[ ? t"d
7
'f>
com.adt.po.User"; D2?7=5DgS
Query query = getSession().createQuery WrG)&&d
l7x%G@1#~W
(querySentence); qY0Ic5wCY
query.setFirstResult(page.getBeginIndex()) |faXl3|
.setMaxResults(page.getEveryPage()); $hE X,
return query.list(); Zmp ^!|=X!
} 5|>jz `
>5 i8%r
} 5 TnECk
kw yvd`J8
^T<<F}@q
*sw$OnVb
>G-D& A+
至此,一个完整的分页程序完成。前台的只需要调用 W5yqnjK
$4
Fh?q;oEj
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;XTP^W!6f
Ybok[5
的综合体,而传入的参数page对象则可以由前台传入,如果用 6~2!ZU
$Z;0/\r%
webwork,甚至可以直接在配置文件中指定。 H7\EvIM=
;ga~ae=Fg
下面给出一个webwork调用示例: Z+vLEEX*uQ
java代码: 4)"jg[
8<g5.$xyz
#cmj?y()
/*Created on 2005-6-17*/ 7,(:vjIXd
package com.adt.action.user; ].Et&v
k@wxN!w;
import java.util.List; zb9$
7%?A0%>6G
import org.apache.commons.logging.Log; R"82=">v
import org.apache.commons.logging.LogFactory; RQh4RUm
import org.flyware.util.page.Page; icnp^2P
A46y?"]/30
import com.adt.bo.Result; k|g~xmI;
import com.adt.service.UserService; IPY@9+]
import com.opensymphony.xwork.Action; M<)HJ lr
gGZ$}vX
/** fYH%vr)
* @author Joa fo5!d@Nv
*/ ikofJl]9
publicclass ListUser implementsAction{ z}pdcQl#
?5+=
privatestaticfinal Log logger = LogFactory.getLog J[<:-$E
\Mi y+<8$
(ListUser.class); 9 s>JdAw?
K\;b3
private UserService userService; IJs`3?
0_%u(?
private Page page; BGUP-_&
Dpof~o,f
privateList users; T"dEa-O
paiF ah
/* ,c7 8O8|
* (non-Javadoc) rt."P20T
* Z!ub`coV[
* @see com.opensymphony.xwork.Action#execute() & }}o9
*/ {
\Q'eL8
publicString execute()throwsException{ +=:CW'B5
Result result = userService.listUser(page); A3h[VnuG,
page = result.getPage(); 3g} ]nj:N
users = result.getContent(); :PjHs Np;^
return SUCCESS; *%Q!22?6F
} s K s
D
/<M08ze
/** >0u4>=#
* @return Returns the page. \5O4}sm$*
*/ zQD$+q5h
public Page getPage(){ J;G+6C$:
return page; zf6k%
} :,:r
` NcWy
/** +]Ydf^rF
* @return Returns the users. &grT}
*/ H{9di\xnEm
publicList getUsers(){ ^TnBtIU-B
return users; p"Fj6T2
} O~ w&4F;{
Rsqb<+7
/** ULAAY$o@5
* @param page 7X1T9'jI2
* The page to set. Xgc@cwd
*/ qifX7AXHr
publicvoid setPage(Page page){ -Vw,9VCF
this.page = page; ,GGr@})
} ?!8M
I,c/
r1xNU0A
/** V[Auw3)
* @param users NtSa#$A
* The users to set. #(!>
*/ lcyan
publicvoid setUsers(List users){ vMDV%E S1t
this.users = users; <+pwGKtD
} l *.#g
AEhh
6v
/** >STWt>s
* @param userService @)|62Dv /
* The userService to set. |%we@
E
*/ PJS\> N&u
publicvoid setUserService(UserService userService){ = K}5 fe
this.userService = userService; IIs'm!"Y>
} WHMt$W}%
} KK}^E_v
i5q
VQo
wjQu3 ,Cj
hH|3s-o
j:\MrYt0H
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, i\2~yXw\
Z6A*9m
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 ]xfu@''
s9@/(_
么只需要: t|%wVj?_
java代码: !A, ]
+A3@{2
| Fm(
<?xml version="1.0"?> uI!rJc>TX
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork PW~+=,
V8 }yK$4b
1.0//EN" "http://www.opensymphony.com/xwork/xwork- [n44;
xP
"7B9B
1.0.dtd"> >@rsh-Z
c54oQ1Q&"
<xwork> ;1A4p`)
yk,o*g
<package name="user" extends="webwork- ehV`@ss
7q^osOj"
interceptors"> y08.R.
l
|Xlpgdiu
<!-- The default interceptor stack name 4(f[Z9 iZ]
db'Jl^
--> B{PI&a9~s%
<default-interceptor-ref M6[&od
&2d^=fih
name="myDefaultWebStack"/> K}L-$B*i
`rN,*kcP
<action name="listUser" I>B-[QEC
4U*J{''L
class="com.adt.action.user.ListUser"> Om,+59ua*
<param Q
&<:W4N*
540-l Me
name="page.everyPage">10</param> d dkh*[
<result 67wY_\m 9I
,|<2wn#q
name="success">/user/user_list.jsp</result> 4RGEg;]S
</action> MuQyHEDF
[kM)K'-
</package> vT#zc)j
Ep>3%{V
</xwork> s{4|eYR
# y%Q{
;!v2kVuS]
R'`q0MoN1
UR>zL3
$e)d!m.
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ^$}9
Enj+Y
6sJN@dFA
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。 4Z12Z@ A#7
M_<O'Ii3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 meA=lg?
,]+P#eXgE
cah1'Y
}(4U7Ac
]h3<r8D_#
我写的一个用于分页的类,用了泛型了,hoho S='AA_jnw
^I*</w8
java代码: /g BB
d!mtSOh
;}"_hLX
package com.intokr.util; [p^N].K$
X`JWYb4
import java.util.List; "7mYs)=
UE3(L
^
/** # -e
* 用于分页的类<br> WvQK$}Ax4N
* 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=4t
* DN3#W w2[r
* @version 0.01 BQu_)@
* @author cheng kclClB:PS
*/ r~&"D#)sy
public class Paginator<E> { #; CC"
privateint count = 0; // 总记录数 >>oR@
privateint p = 1; // 页编号 #9M6 q
privateint num = 20; // 每页的记录数 YNyaz\L
privateList<E> results = null; // 结果 MB06=N
veIR)i@dx
/** %xF
j;U?
* 结果总数 azF|L"-RP
*/ (L}
publicint getCount(){ rH
Et]Xa
return count; >{?~cNO&
} _:DnF
,#:* dl
publicvoid setCount(int count){ 6;6a.iZ
this.count = count; v6(Yz[
} G-
wQ
weJ9
+aR.t@D+"Y
/** D;VQoO
* 本结果所在的页码,从1开始 &/R`\(hEA
* - e0C
Bp
* @return Returns the pageNo. &D0suK#
*/ zO8`xrN!
publicint getP(){ uTTM%-DMHT
return p; })RT2zw}
} ?@8[1$1a
.@KpN*`KH
/** golr,+LSo
* if(p<=0) p=1 {@, } M
* #2l6'gWE0
* @param p XHU&ix{Od
*/ hiO:VA
publicvoid setP(int p){ A`_(L|~
if(p <= 0) kzU;24"K
p = 1; U'(}emh}
this.p = p; /)fx(u#
} Rj6:.KEJ
GPlAQk
/** pie<jZt
* 每页记录数量 *qdf?'R
*/ hd{Vz{;W
publicint getNum(){ ?|!167/O
return num; /^ *GoB
} 3 d
$
_%^t[4)q
/** \)Jv4U\;
* if(num<1) num=1 7oaa)
*/ !_0kn6S5
publicvoid setNum(int num){ LoZ8;VU
if(num < 1) mw0#Dhyy1=
num = 1; jusP
aAdW
this.num = num; h<;kj#qbb
} nn><
k"
R-nC+)^
/** at7|r\`?-
* 获得总页数 0w^\sf%s
*/ s33< }O0
publicint getPageNum(){ rK&ofc]f$
return(count - 1) / num + 1; .Rl58]x~
} EGMj5@>
s!S,;H
/** 5"(AqXoq
* 获得本页的开始编号,为 (p-1)*num+1 t95hI DtD
*/ clfi)-^{K
publicint getStart(){ F jdh&9Zc
return(p - 1) * num + 1; $__e7
} K8E:8`_cx
~@a7RiE@
/** @?ntMh6
* @return Returns the results. q@ !p
*/ VesW7m*z
publicList<E> getResults(){ fq-$u;~h
return results; 8\c=Un
} {MX_t/o=f
86d*
public void setResults(List<E> results){ |rJ_
this.results = results; %4QCUc*lr
} dLOUL9hf
N{Og; roGD
public String toString(){ xR+=F1y
StringBuilder buff = new StringBuilder f:iK5g
Ht^MY
(); =w&%29BYq
buff.append("{"); [{3WHS.
buff.append("count:").append(count); <()xO(
buff.append(",p:").append(p); $s2Ty1
buff.append(",nump:").append(num); etF?,^)h=g
buff.append(",results:").append \ZrLh,6f.
K@xp!
(results); m(JFlO
buff.append("}"); xo{f"8}^
return buff.toString(); rhFa rm4a
} U!m-{7s$
i[FcY2
} w7\:S>;(O"
zSta!]
pNpj, H*4