Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 C.#\Pz0
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1DTA Dh0
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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 ='\Di '*
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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 TV['"'D&i
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。 4/Mi-ls_
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分页支持类: 2omKP,9,2
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java代码: gZg5On
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package com.javaeye.common.util; @[=K`n:n_
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import java.util.List; ,$,c<M
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publicclass PaginationSupport { q!O B?03n
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publicfinalstaticint PAGESIZE = 30; 2VZdtz
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privateint pageSize = PAGESIZE; xh90qm
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privateList items; |Y9mre.Y;
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privateint totalCount; ?x\tE]
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privateint[] indexes = newint[0]; d41DcgG'j(
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privateint startIndex = 0; qb[UA5S\`
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public PaginationSupport(List items, int AWG;G+
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totalCount){ O^L#(8bC
setPageSize(PAGESIZE); w y\0o
setTotalCount(totalCount); J?1U'/Wx2
setItems(items); "J_#6q*
setStartIndex(0); [#3*R_#8R
} Rt6(y #dF
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public PaginationSupport(List items, int 1[4)Sq?
q; n
totalCount, int startIndex){ d'okXCG
setPageSize(PAGESIZE); gR]NH
setTotalCount(totalCount); LT2UY*
setItems(items); FD*)@4<o
setStartIndex(startIndex); [e6zCN^t
} ;WqWD-C
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public PaginationSupport(List items, int Nj^:8]D)0
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totalCount, int pageSize, int startIndex){ *pP&$!bH%
setPageSize(pageSize); 3%0ShMFP@
setTotalCount(totalCount); {~y,.[Ga
setItems(items); knS(\51A
setStartIndex(startIndex); VUF$,F9
} h't!1u
4[P]+Z5b+
publicList getItems(){ j]X$7
return items; tEbR/?,GI
} ~TvKMW6/#
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publicvoid setItems(List items){ 6A;,Ph2
this.items = items; !VoAN5#;
} hUo}n>Aa
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publicint getPageSize(){ 6 *GR_sMm
return pageSize; Ks>l=5~v|
} }NgevsV>;
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publicvoid setPageSize(int pageSize){ G oHdhne3
this.pageSize = pageSize; +;|" #
} |vUjoa'.7E
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publicint getTotalCount(){ _ mJP=+i
return totalCount; GX\6J]x=^2
} 8rEUZk
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publicvoid setTotalCount(int totalCount){ .I#ss66h
if(totalCount > 0){ {Y7dE?!`7
this.totalCount = totalCount; ,jc')#]9B
int count = totalCount / vWh]1G#'p[
&&s3>D^Ta
pageSize; f$|AU-|<
if(totalCount % pageSize > 0) Ix59(g
count++; ~_GW
indexes = newint[count]; |~d8j'rt
for(int i = 0; i < count; i++){ TaqqEL
indexes = pageSize * .VG5 / 6zp
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i; [~v1
} CUI\:a-
}else{ K4w#}gzok
this.totalCount = 0; N7l`-y
} 6M^NZ0~J
} _B6W:k|-7l
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publicint[] getIndexes(){ /9o
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return indexes; cqSo%a2
} vvwQ/iJO4Q
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publicvoid setIndexes(int[] indexes){ dZ6P)R
this.indexes = indexes; Pz77\DpFi
} ~\]lMsk+
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publicint getStartIndex(){ EU,f;H
return startIndex; e{6I-5`|,#
} 0n)99Osq(u
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publicvoid setStartIndex(int startIndex){ - xE%`X
if(totalCount <= 0) Po*G/RKu4W
this.startIndex = 0; ??
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elseif(startIndex >= totalCount) E-v#G~
this.startIndex = indexes |]UR&*
N/V~>UJ0{*
[indexes.length - 1]; sL",Ho
elseif(startIndex < 0) 1{Kv
this.startIndex = 0; Muay6b?
else{ WXmR{za
this.startIndex = indexes d$}!x[g$Z
{?YBJnG}x
[startIndex / pageSize]; u_ *DS-
} (O-.^VV
} k,h
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publicint getNextIndex(){ QJ^'Uyfdn
int nextIndex = getStartIndex() + my+2@ln
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pageSize; ZFFKv
if(nextIndex >= totalCount) k"$E|$
return getStartIndex(); W&Xm_T[Q
else IZSJ+KO
return nextIndex; <nk7vo?Ks
} e anR$I;Yj
N% !TFQf
publicint getPreviousIndex(){ CY</v,\:#
int previousIndex = getStartIndex() - ,~nrNkhp
Cw$7d:u
pageSize; M$$Lsb [
if(previousIndex < 0) (CR]96n
return0; kD\7wz,ui
else h#~\-j9>
return previousIndex; Qk[YF
} 0@LC8Bz+'
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} d9Uv/VGp
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抽象业务类 #gc v])to
java代码: Q`)iy/1M
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/** i}=n6
* Created on 2005-7-12 i1JVvNMQ,
*/ (8td0zq
package com.javaeye.common.business; 9NC?J@&B
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import java.io.Serializable; 4d63+iM+}
import java.util.List; 1haNpLfS>
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import org.hibernate.Criteria; e pGC
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import org.hibernate.HibernateException; PR3&LI;B*
import org.hibernate.Session; PdqyNn=
import org.hibernate.criterion.DetachedCriteria; ZE:!>VXa87
import org.hibernate.criterion.Projections; vJ9IDc|[
import /I48jO^2
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{<&:%(
org.springframework.orm.hibernate3.HibernateCallback; _@@.VmZL
import .X\9vVJ
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org.springframework.orm.hibernate3.support.HibernateDaoS 1{-yF :A
bR'UhPs-8;
upport; 3XSfXS{lwP
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import com.javaeye.common.util.PaginationSupport; r?2J
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public abstract class AbstractManager extends 3,^.
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HibernateDaoSupport { KXT9Wt=
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privateboolean cacheQueries = false; C17$qdV/
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privateString queryCacheRegion; C+%6N@
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publicvoid setCacheQueries(boolean ApTE:Fm1
b_w(F_0
cacheQueries){ &a!MT^anA~
this.cacheQueries = cacheQueries; !X4m6gRaP
} CLgfNrW~
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publicvoid setQueryCacheRegion(String ?+G
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queryCacheRegion){ c>%%'c
this.queryCacheRegion = ^i!I0Q2yd
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queryCacheRegion; !,9;AMO
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} Cg3 d
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publicvoid save(finalObject entity){ 61Wh %8-
getHibernateTemplate().save(entity); LV@tt&|N
} x4XCR,-
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publicvoid persist(finalObject entity){ ![&9\aH
getHibernateTemplate().save(entity); ^l{q{O7U$
} F$@(0c
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publicvoid update(finalObject entity){ 4SJb\R)XK
getHibernateTemplate().update(entity); I~Q
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} opgNt o6$
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publicvoid delete(finalObject entity){ Slv91c&md,
getHibernateTemplate().delete(entity); w >w zV=R
} |3G;Rh9w,
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publicObject load(finalClass entity, +1nzyD_E
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finalSerializable id){ >e!Y 63`
return getHibernateTemplate().load .'bhRQY
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(entity, id); +-NH
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} Hm'aD2k
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publicObject get(finalClass entity, uj@d {AQ
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finalSerializable id){ 8'M:uI
return getHibernateTemplate().get {a0yHy$H
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(entity, id); zy`T!
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} r3dGXiu
o>HU4O}
publicList findAll(finalClass entity){ \V
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return getHibernateTemplate().find("from hA1p#
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" + entity.getName()); d:{}0hmxI
} S]Ye`
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publicList findByNamedQuery(finalString oSLm?Lu
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namedQuery){ o(yyj'=(
return getHibernateTemplate 0UhJ
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().findByNamedQuery(namedQuery); bnZ H
} x/0loW?q^
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publicList findByNamedQuery(finalString query, S0`u!l89(
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finalObject parameter){ L*cP8v4
return getHibernateTemplate U |Uc|6
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().findByNamedQuery(query, parameter); 54#P
}
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publicList findByNamedQuery(finalString query, \027>~u
{
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finalObject[] parameters){ MzH'<`;BP
return getHibernateTemplate MlR]+]
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().findByNamedQuery(query, parameters); W;?e @}
} OZEbs 7
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publicList find(finalString query){ $b)t`r+
return getHibernateTemplate().find (4|R}jv
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(query); D!z'Y,.
} 2I283%xr
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publicList find(finalString query, finalObject Lngf,Of.e
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parameter){ 0U8'dYf
return getHibernateTemplate().find v#?;PyeF
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(query, parameter); 'Y/kF1,*
} fZcA{$Vc]N
}WhRJr`a
public PaginationSupport findPageByCriteria wVs"+4l<
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(final DetachedCriteria detachedCriteria){ 5?[hr5E.E
return findPageByCriteria >+DMTV[O
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }R/we`
} %/
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public PaginationSupport findPageByCriteria Bo\~PV[
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(final DetachedCriteria detachedCriteria, finalint x~=Mn%Ew0
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startIndex){ 7$x%A&]
return findPageByCriteria 1OV] W
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(detachedCriteria, PaginationSupport.PAGESIZE, *Q#oV}D_
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startIndex); a_-@rceU
} O*.n;_&
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public PaginationSupport findPageByCriteria 5~ZzQG
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(final DetachedCriteria detachedCriteria, finalint =zu;npM
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pageSize, Xppv
finalint startIndex){ p{:y?0pGN
return(PaginationSupport) CM%;/[WBxy
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getHibernateTemplate().execute(new HibernateCallback(){ +o):grWvQ
publicObject doInHibernate QN|=/c<U
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(Session session)throws HibernateException { sWB@'P:x
Criteria criteria = eiXl"R^
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detachedCriteria.getExecutableCriteria(session); [!MS1vc;
int totalCount = 9dm<(I}
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((Integer) criteria.setProjection(Projections.rowCount n_:EWm$\
pe<T"[X
()).uniqueResult()).intValue(); ]0BX5Z'
criteria.setProjection R.DUfU"gp
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(null); *?$M=tH
List items = n`@dk_%yI
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} X
criteria.setFirstResult(startIndex).setMaxResults 'sNiJ >
~ch%mI~
(pageSize).list(); ,fqM>Q
PaginationSupport ps = L62%s[
}"SqB{5e(
new PaginationSupport(items, totalCount, pageSize, wX_~H*m?
>2=
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startIndex); e ;^}@X
return ps; GgnR*DVP$
} C| 2|OTtQ
}, true); ~mwIr
} QPh3(K1w^
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public List findAllByCriteria(final X;2LK!x;y
fms(_Q:R?
DetachedCriteria detachedCriteria){ cA|vH^:
return(List) getHibernateTemplate sOiM/}O]
e /1x/v'
().execute(new HibernateCallback(){ +95v=[t#Ut
publicObject doInHibernate bC~I}^i\
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(Session session)throws HibernateException { t`{T:Tjc
Criteria criteria = 1e7I2g
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detachedCriteria.getExecutableCriteria(session); (9kR'kr
return criteria.list(); 3Pgokj
} >\3\&[#"
}, true); Ok|Dh;1_
} VIN0kRQ#
bar=^V)
public int getCountByCriteria(final 8ZqLGa]
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DetachedCriteria detachedCriteria){ 0xO*8aKT
Integer count = (Integer) n\V7^N
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getHibernateTemplate().execute(new HibernateCallback(){ jwBJG7\
publicObject doInHibernate <pjxJ<1l
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(Session session)throws HibernateException { f8aY6o"i
Criteria criteria = eG8l^[
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detachedCriteria.getExecutableCriteria(session); ("r:L<xe&
return Ir5|H|b<
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criteria.setProjection(Projections.rowCount q mv0 LU
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()).uniqueResult(); T:Ee6I 3l
} H0sTL#/L \
}, true); EU>`$M&w-
return count.intValue(); ^]'_Qbi]}
} esQ$.L
} "tl$JbRTY
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用户在web层构造查询条件detachedCriteria,和可选的 l'aCpzf
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4#7*B yvf
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PaginationSupport的实例ps。 OG$v"Yf~
@ \XeRx;
ps.getItems()得到已分页好的结果集 Ie(.T2K
ps.getIndexes()得到分页索引的数组 o kA<
ps.getTotalCount()得到总结果数 %D8.uGsh
ps.getStartIndex()当前分页索引 3+s$K(% I
ps.getNextIndex()下一页索引 pMy:h
ps.getPreviousIndex()上一页索引 "y&`,s5}
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/*k_`3L
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 `]XI Q\ *
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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 0V21_".S
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一下代码重构了。 Bf;_~1+vLG
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我把原本我的做法也提供出来供大家讨论吧: q~[sKAh
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首先,为了实现分页查询,我封装了一个Page类: uf9&o#
java代码: |\?u-O3
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/*Created on 2005-4-14*/ |rwY
package org.flyware.util.page; rzn,NFI
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/** wW1\{<hgr
* @author Joa 4C%pKV
* <Nqbp
*/ Es)|#0m\x@
publicclass Page { Y$\|rD^f
matna
/** imply if the page has previous page */ c>{QTI:]
privateboolean hasPrePage; M3O !jN~
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/** imply if the page has next page */ $*iovam>^]
privateboolean hasNextPage; ?z&%VU"
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/** the number of every page */ SeDk/}/~e
privateint everyPage; ;%^=V#
->{-yh]jv
/** the total page number */ #0[^jJ3J
privateint totalPage; E'DHO2
Y
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/** the number of current page */ 7g(Z@
privateint currentPage; (BeJ,K7
qrw
/** the begin index of the records by the current *|dK1'Xr
Pap6JR{7
query */ 2a48(~<_
privateint beginIndex; U|%}B(
+jwHYfAK)
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/** The default constructor */ tLa%8@;'$
public Page(){ |oXd4
ZDbe]9#Xh
} Q]/%Y[%|
n*=#jL
/** construct the page by everyPage w"s@q$}]8M
* @param everyPage FZj>N(
* */ k-=LD
public Page(int everyPage){ aW&)3C2-x
this.everyPage = everyPage; II}M|qHaK
} iP"sw0V8
+|,4g_(j
/** The whole constructor */ XgHJ Oqt
public Page(boolean hasPrePage, boolean hasNextPage, -"dt3$ju
e@ZM&iR
m\0_1 #(
int everyPage, int totalPage, /~ {`!30
int currentPage, int beginIndex){ +)"Rv%.
this.hasPrePage = hasPrePage; U\tx{CsSz
this.hasNextPage = hasNextPage; l9&k!kF`
this.everyPage = everyPage; qrlC
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this.totalPage = totalPage; 9DNp
this.currentPage = currentPage; SI+Uq(k
this.beginIndex = beginIndex; KRC"3Qt
} oIj=ba(n1
3^+D,)#D^
/** (;},~( 2B
* @return IUFc_uL@\
* Returns the beginIndex. F9u?+y-xb
*/ 5MAfuHq^
publicint getBeginIndex(){ ^F+7<$2
return beginIndex; "
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} ;: 2U}p^-
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/** 3>aEP5
* @param beginIndex bPU
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* The beginIndex to set.
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*/ lFyDH{!
publicvoid setBeginIndex(int beginIndex){ w&aZ 97{
this.beginIndex = beginIndex;
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} bH e'
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/** #Or;"}P>fB
* @return o6k#neB>=.
* Returns the currentPage. $zjdCg<
*/ 5?^L))
publicint getCurrentPage(){ x1.S+:
return currentPage; :]m.&r S,
} + '_t)k^
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/** rQVX^
* @param currentPage F#sm^% _2
* The currentPage to set. w>&*-}XX
*/ w31Ox1>s
publicvoid setCurrentPage(int currentPage){ QkdcW>:a7
this.currentPage = currentPage; y(p_Unm
} r[a7">n
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/** J{1H$[W~}
* @return 7~mhWPzMwB
* Returns the everyPage. 7#0buXBg
*/ sI!H=bp-8
publicint getEveryPage(){ &xQM!f
return everyPage; 3c=kYcj
} 00QJ596
KkA)p/
/** t~->&Ja
* @param everyPage LKu\M h|
* The everyPage to set. S%i^`_=Q
*/ ZNX38<3h
publicvoid setEveryPage(int everyPage){ tX{yR'Qhu
this.everyPage = everyPage; pa[/6(
} ~P1~:AT
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/** K
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* @return ,_Z(!|
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* Returns the hasNextPage. 8Y?M:^f~
*/ >1Z"5F7=
publicboolean getHasNextPage(){ 'rcqy1-&
return hasNextPage; v3I^81
} ,yYcjs!=o
4N,mcV
/** EO&Q
* @param hasNextPage $oK&k}Q
* The hasNextPage to set. *|fF;-#v
*/ +(3_V$|Dv
publicvoid setHasNextPage(boolean hasNextPage){ ::|~tLFu
this.hasNextPage = hasNextPage; qz-QVY,
} 2X?GEO]/4
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/** t<!;shH,s
* @return j~Aq-8R=
* Returns the hasPrePage. kOYUxr.b
*/ 4+RR`I8$Ge
publicboolean getHasPrePage(){ @%]A,\
return hasPrePage; M3pE$KT0x
} u5(8k_7
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/** -zR<m
* @param hasPrePage +WH\,E
* The hasPrePage to set. &]nx^C8V;
*/ %;,fI'M
publicvoid setHasPrePage(boolean hasPrePage){ ci~#G[_$S
this.hasPrePage = hasPrePage; z%82Vt!a5
} 7zb^Z]
b dgkA
/** }e?H(nZS7h
* @return Returns the totalPage. /<J(\;Jr6
* .-KI,IU
*/ $5R2QNg n
publicint getTotalPage(){ P!eo#b^S
return totalPage;
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} *GT=U(d
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/** m\L`$=eO8
* @param totalPage b2m={q(s
* The totalPage to set. Zse&{
*/ $9)os7H7
publicvoid setTotalPage(int totalPage){ ;w7 mr1
this.totalPage = totalPage; y6XOq>
} WAa45G
B*(]T|ff<
} utlr|m Xc
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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 a+w2cN'
QNj]wm=mp
个PageUtil,负责对Page对象进行构造: {M]_]L{&7
java代码: G;Li!H
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s2;~FK#/
/*Created on 2005-4-14*/ uoS:-v}/Y~
package org.flyware.util.page; G{U#9
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import org.apache.commons.logging.Log; i\i%WiRl
import org.apache.commons.logging.LogFactory; U\KMeaF5e-
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/** T
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* @author Joa (bsx|8[
* U"PcNQy
*/ (2g
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publicclass PageUtil { ;8s L
f9.?+.^_
privatestaticfinal Log logger = LogFactory.getLog hyI7X7Hy
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(PageUtil.class); 9LDv?kYr
$DbnPZ2$
/** 17LhgZs&
* Use the origin page to create a new page 5 ~Wg=u<6
* @param page Z>hTL_|]a{
* @param totalRecords ;*A'2ymXUT
* @return 4Yj1Etq.E
*/ pRd.KY -<
publicstatic Page createPage(Page page, int #[+# bw_6
]I?.1X5d0
totalRecords){ 380` >"D
return createPage(page.getEveryPage(), ^P)f]GQx
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page.getCurrentPage(), totalRecords); #@R0$x
} B
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/** ]; w 2YR
* the basic page utils not including exception P`Np+E#I
LgqQr6y"
handler hlzB
cz*
* @param everyPage ]3KeAJ
* @param currentPage }A)\bffH
* @param totalRecords 3BFOZV+
* @return page 9/ <3mF@E
*/ Q]ersA8 V>
publicstatic Page createPage(int everyPage, int |Y9>kXM l
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currentPage, int totalRecords){ hZ&KE78?
everyPage = getEveryPage(everyPage); Pfd1[~,
currentPage = getCurrentPage(currentPage); FuhmLm'p
int beginIndex = getBeginIndex(everyPage, 0=Z[6Q@:
YF%gs{
currentPage); >!963>D R
int totalPage = getTotalPage(everyPage, n;g'?z=hy
5ZCu6A
totalRecords); CIudtY(:
boolean hasNextPage = hasNextPage(currentPage, NR4+&d
8wU$kK
totalPage); p.DQ|?
boolean hasPrePage = hasPrePage(currentPage); h4Crq Yxa_
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returnnew Page(hasPrePage, hasNextPage, ,81%8r
everyPage, totalPage, vy<W4
currentPage, +|A`~\@N
9vI~vl l
beginIndex); w"hd_8cO
} BU`X_Z1)
-f+#j=FX
privatestaticint getEveryPage(int everyPage){ odv2 (\
return everyPage == 0 ? 10 : everyPage; S
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} kDmm
R9XU 7_3B
privatestaticint getCurrentPage(int currentPage){ t{md&k4
return currentPage == 0 ? 1 : currentPage; YQMWhC,8hy
} ^Q/*on;A,/
[+ud7l
privatestaticint getBeginIndex(int everyPage, int $8tk|uh
(s};MdXIz
currentPage){ ,AP&N'
return(currentPage - 1) * everyPage; X/5m}-6d]
} c~ss^[qx|
RD$:.
privatestaticint getTotalPage(int everyPage, int dlu*s(O"
.-gJS-.c
totalRecords){ D,#UJPyg
int totalPage = 0; #{i*9'
waMF~#PJlt
if(totalRecords % everyPage == 0) }7 N6nZj`
totalPage = totalRecords / everyPage; = Xgo}g1
else lC<;Q*Y
totalPage = totalRecords / everyPage + 1 ; O1c%XwMn^
Z#[?~P
return totalPage; JEjxY&
} \!u<)kkyT
Lqgrt]L_"
privatestaticboolean hasPrePage(int currentPage){ ,H=k5WA4m
return currentPage == 1 ? false : true; !KHgHKEW^
} uibmQ|AQ
XKp&GE@Y
privatestaticboolean hasNextPage(int currentPage, 8^7Oc,:~
ug3\K83aj/
int totalPage){ 09kR2(nsW/
return currentPage == totalPage || totalPage == ww2mL
<B
ztp|FUi
0 ? false : true; e@D_0OZ
} EX,>V,.UV
EPm~@8@"j?
: auR0FE
} *`>BOl+ro
;[ <(4v$
= oAS(7o
`YhGd?uu$
zv]ZEWVzc
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。 A3]A5s6
<PLAAh8
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 b:==:d:0s
mjeJoMvN)H
做法如下: #g{R+#fm
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Yy *=@qu>g
VD=H=Ju
的信息,和一个结果集List: p-4$)w~6i
java代码: mixsJ}e
PTe L3L
*X0>Ru[
/*Created on 2005-6-13*/ | {9<%Ok4P
package com.adt.bo; abo=v<mR
.}IW!$
dq
import java.util.List; O}M-6!%<,
W[2]$TwT
import org.flyware.util.page.Page; Xa[k=qFo
=j.TDv'^nd
/** t3<MoDe7`r
* @author Joa sz9W}&(j
*/ bzr2Zj{4
publicclass Result { ]$smFF
'ZbWr*bo
private Page page; *HoRYCL
*.W3V;K
private List content; -.Wcz|
gAAC>{Wh
/** -S$F\%
* The default constructor Xa`Q;J"h
*/ 5kGniG?T#
public Result(){ F0$w9p
super(); ale'-V)5
} Fp\;j\pfw
)qy?x7
/** bP18w0>,
* The constructor using fields ,`geOJn'
* s%)f<3=a
* @param page ;Y7'U rn
* @param content #Y7jNrxE
*/ ~[;r)
g\
public Result(Page page, List content){ V}y]<
this.page = page; sT^R0Q'>
this.content = content; MK1\
} k]m ~DVS
P$EiD+5#z
/** jVff@)_S
* @return Returns the content. Kg%9&l
*/ P:{Aqn~zR
publicList getContent(){ WvfP9(-
return content; J"aw 1
} ZHTi4JY
1T!o`*
/** A
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* @return Returns the page. A@V$~&JCL5
*/ g,,wG k
public Page getPage(){ ?fxM1<8
return page; g89@>?Mn
} H^d?(Svh
l7-lXl"%q
/** Tg{5%~L]
* @param content #/oH #/?
* The content to set. +ktv:d
*/ #W~jQ5NS\
public void setContent(List content){ sOhn@*X
this.content = content; Qs1CK;+zU
} p:08q
B|uQ
?%,LZw^[
/** T5:Q_o]
* @param page |Y3w6 !$
* The page to set. *w0!C:mL&
*/ >7W)iwF
publicvoid setPage(Page page){ +>PsQ^^x
this.page = page; $hm[x$$
} QuR}6C
} cL9gaD$;)
u}du@Aq
5*44QV
vl:~&I&y;R
9]eG|LFD
2. 编写业务逻辑接口,并实现它(UserManager, 7O55mc>cF
9&sb,^4
UserManagerImpl) 0YiTv;mq;
java代码: \Oq2{Sx\
;EBKzB
i:s=
/*Created on 2005-7-15*/ _r:Fmn_%-
package com.adt.service; ad}8~6}_&
71{Q#%5U~
import net.sf.hibernate.HibernateException; ~Dt$}l-9
'g%:/lwA
import org.flyware.util.page.Page; SH)-(+72d
,5W7a
import com.adt.bo.Result; }ny7LQ
j|KDgI<0
/** -,yp?<
* @author Joa ]Thke 4
*/ t4oD> =,92
publicinterface UserManager { rl}<&aPH
KKC%!Xy
public Result listUser(Page page)throws F!z ^0+H(
2E1`r@L
HibernateException; f2e;N[D
D$>!vD'
} 8i',~[
I8XP`Ccq
^6 wWv&G[8
sU>IETo
P*KIk~J
java代码: t+v%%N_
o< @![P
rd7p$e=i
/*Created on 2005-7-15*/ -Cyo2wk
package com.adt.service.impl; {py%-W
xX-r<:'tmi
import java.util.List; Krae^z9R
Ao\P|K9MyL
import net.sf.hibernate.HibernateException; YrnC'o`
DgT]Nty@b
import org.flyware.util.page.Page; 5Npxs&Ea
import org.flyware.util.page.PageUtil; ]hV!lG1_
UOb`@#
import com.adt.bo.Result;
]@ruizb8
import com.adt.dao.UserDAO; 1^|#QMT
import com.adt.exception.ObjectNotFoundException; *v%y;^{k[/
import com.adt.service.UserManager; x+cL(R
uH*6@aYPo
/** j""ZFh04
* @author Joa $
64up!
*/ *Z#OfB4}
publicclass UserManagerImpl implements UserManager { m ""+$
uXc;!*
private UserDAO userDAO; i D 9 */
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/** [mzed{p]]
* @param userDAO The userDAO to set. KO" /
*/ R=~%kt_n
publicvoid setUserDAO(UserDAO userDAO){ y"yo\IDW
this.userDAO = userDAO; 1)k+v17]f5
} m[eqTh4*
-6+7&.A+
/* (non-Javadoc) P4@`C{F5m
* @see com.adt.service.UserManager#listUser (tYZq86`
Z3JUYEAS
(org.flyware.util.page.Page) JuSS(dJw
*/ J$}]p
public Result listUser(Page page)throws m\qeYI6, Z
eN<L)a:J_
HibernateException, ObjectNotFoundException { HQ@g6
int totalRecords = userDAO.getUserCount(); 4Kch=jt4#
if(totalRecords == 0) [2-n*a(q
throw new ObjectNotFoundException *k7BE_&*0Z
kqCsEtm]
("userNotExist"); A'#d:lOA
page = PageUtil.createPage(page, totalRecords); -gvfz&Lz
List users = userDAO.getUserByPage(page); ?#w} S%
returnnew Result(page, users); ktrIi5B
} Xr
<H^X
l_}d Q&R
} IW~wO
`h@fW- r
\96\!7$@O
QdgJNT<=H,
;mEn@@{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 O q$_ q
UF7h{V})
询,接下来编写UserDAO的代码: f|,Kh1{e
3. UserDAO 和 UserDAOImpl: 2]vTedSOl
java代码: %)7t2D
HaVhdv3L
j Mn,N9Mf
/*Created on 2005-7-15*/ yMWh#[phH
package com.adt.dao; e' M&Eh
Imv#7{ndq
import java.util.List; @$jV"Y
cTGd<
import org.flyware.util.page.Page; %g@?.YxjT
7
0?iZIK _
import net.sf.hibernate.HibernateException; WnG2\(U
qm$(_]R~`
/** $A?9U}V#^
* @author Joa ,jRAVt+{N
*/ vS\ 2zwb}
publicinterface UserDAO extends BaseDAO { :e7\z
o,WjM[e
publicList getUserByName(String name)throws 9" q-Bb
hY.i`sp*/
HibernateException; 3q'AgiW
d~~kJKK
publicint getUserCount()throws HibernateException; e4` L8
3A`Gx#
publicList getUserByPage(Page page)throws e%[*NX/
At\(/Zy
HibernateException; 1<G+KC[F
x.-d)]a!
} ?Ujg.xo\
gl+d0<Rzw
jae9!Wi
/-p!|T}w
K#+?oFo:
java代码: {|u"I@M*O
@#4-4.6I<x
2yK">xYY@
/*Created on 2005-7-15*/ ]^C 8Oh<
package com.adt.dao.impl; 1_TuA(
T`!R
ki%~
import java.util.List; VVDN3
@F5Af/
import org.flyware.util.page.Page; *U^Y@""a
j4owo#OB-
import net.sf.hibernate.HibernateException; ,*iA38d.!
import net.sf.hibernate.Query; bqE'9GI
D[yyFo,z
import com.adt.dao.UserDAO; ]$ "eGHX
8NHm#Z3Ol
/** 6|NH*#s
* @author Joa @N4~|`?U
*/ .v+JV6!u
public class UserDAOImpl extends BaseDAOHibernateImpl 2#7|zhgb
Zkd{EMW
implements UserDAO { !uGfS' Vl
Q7uJ9Y{X
/* (non-Javadoc) 96^aI1:
* @see com.adt.dao.UserDAO#getUserByName lndz
N_T5sZ\
(java.lang.String) &q>8D'
*/ e\C-a4[C8P
publicList getUserByName(String name)throws dQ8RrD=$&
U:TkO=/>:
HibernateException { V8/d27\
String querySentence = "FROM user in class -US:a8`
zz*PAYl.
com.adt.po.User WHERE user.name=:name"; [8Pt$5]^
Query query = getSession().createQuery :dt[ #
fc+-/!v
(querySentence); <;Hb7p3N
query.setParameter("name", name); zhw*Bed<
return query.list(); B!/kC)bF:
} A5Hx$.Z
6nk}k]Ji
/* (non-Javadoc)
RU~na/3
* @see com.adt.dao.UserDAO#getUserCount() !Axe}RD'
*/ :C_/K(Rkl
publicint getUserCount()throws HibernateException { aLh(8 ;$
int count = 0; sYS
8]JU
String querySentence = "SELECT count(*) FROM #p(c{L!
t,9+G<)>H
user in class com.adt.po.User"; 2V@5:tf
Query query = getSession().createQuery *5PQ>d
G
naaKAZ!S
(querySentence); YcA. Bn|as
count = ((Integer)query.iterate().next %k#+nad
b23A&1X
()).intValue(); n 0=]C%wr
return count; &|XgWZS5
} ATkd# k%S
zjUQ]
/* (non-Javadoc) Gt&yz"?D
* @see com.adt.dao.UserDAO#getUserByPage %"f85VfZ
9Q1%+zjjMq
(org.flyware.util.page.Page) sg,\!'
*/ ` &A`&-nc=
publicList getUserByPage(Page page)throws J,Ki2'=
50MM05aC
HibernateException { Tm`@5
String querySentence = "FROM user in class rT `sY
xq;>||B
com.adt.po.User"; ]S%_&ZMCM
Query query = getSession().createQuery FXr^ 4B}
^(TCUY~f&
(querySentence); '^)'q\v'k
query.setFirstResult(page.getBeginIndex()) qefp3&ls
.setMaxResults(page.getEveryPage()); Gt*<Awn8
return query.list(); :z8/iD y
} zh2<!MH
f$>_>E
}
\uTlwS
{LiJ=Ebt
1vo3aF
=u2~=t=LV
|>(Vo@
至此,一个完整的分页程序完成。前台的只需要调用 9\Gk)0
eI
( S)q
userManager.listUser(page)即可得到一个Page对象和结果集对象 T)e2IXGN
fc~fjtqwvz
的综合体,而传入的参数page对象则可以由前台传入,如果用 m^oG9&";
OFr"RGW"
webwork,甚至可以直接在配置文件中指定。 V30w`\1A
}`L;.9
下面给出一个webwork调用示例: MX]#|hEeQ
java代码: m u9,vH
z/91v#}.
6H0kY/quL|
/*Created on 2005-6-17*/ f1:>H.m`
package com.adt.action.user; -Cvd3%Jje
|vd|;" `
import java.util.List; \Yj_U'2"i
WblH}
import org.apache.commons.logging.Log; QyA^9@iVs
import org.apache.commons.logging.LogFactory; #Tc`W_-
import org.flyware.util.page.Page; Mcc%&j
3DO*kM1s@
import com.adt.bo.Result; J?{sTj"KB
import com.adt.service.UserService; 9 5!xJdq
import com.opensymphony.xwork.Action; w(bvs&`{uC
F7<M{h5s
/** +On2R&m
* @author Joa imADjBR]
*/ 1CJ1-]S(3
publicclass ListUser implementsAction{ Lf9s'o}.R
z2V ->UK)
privatestaticfinal Log logger = LogFactory.getLog ^N7cX K*
Srw`vql{(
(ListUser.class); o Tvg%bX
z@UH[>^gj
private UserService userService; @wD#+Oz
O)^F z:
private Page page; kR1
12J9P
]foS.D,
privateList users; ,sj(g/hg
c
k[uvH
/* )PR`irw
* (non-Javadoc) <,O|fY%
* yUcU-pQ
* @see com.opensymphony.xwork.Action#execute() 4%}iKoT
*/ G-D}J2r=F
publicString execute()throwsException{ EiD41N
Result result = userService.listUser(page); 0<uL0FOT
page = result.getPage(); KYkS^v
users = result.getContent(); rk%pA-P2
return SUCCESS; %l%ad-V
} ih("`//nP
Eva&FHRTY
/** i=^6nwD&
* @return Returns the page. _l)3pm6
*/ L|{v kkBo
public Page getPage(){ -^_^ByJe
return page; :
HU|BJ>
} [2Y@O7;nI
@sa_/LH!K
/** y z3=#
* @return Returns the users. KD\%B5Jy
*/ D|Tz{DRG
publicList getUsers(){ Bs3&yEq(
return users; on
hLhrZ
} mb_6f:Qh3
DIYR8l}x
/** A~{vja0?
* @param page vx$DKQK@l\
* The page to set. yEB#*}K?
*/ j<WsFVS
publicvoid setPage(Page page){ Md9y:)P@Y
this.page = page; b$Ei>%'/";
} @(6P L^I
iqoMQ7%
/** tw 3zw`o:
* @param users P7X3>5<;q
* The users to set. Z9MU%*N
*/ Le-t<6i-V#
publicvoid setUsers(List users){ 'o=DGm2H
this.users = users; ',+Zqog92
} ^Et^,I:`
L09r|g4Z
/** N:KM8PZ&~
* @param userService hw`pi6
* The userService to set. 6[FXgCb
*/ {qSMJja !t
publicvoid setUserService(UserService userService){ jc32s}/H
this.userService = userService; m+dQBsz\
} K{Nj-Rqd
} butBS
-oZw+ge}
T#e|{ZCbq
N3Q
.4?
z9
Z>/
*q2
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, I(3YXv
VN
D{6BX-Dw.
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ]2&RN@
tJ7tZ~Ak
么只需要: Z" l].\=
F
java代码: 0}`
-<(
`Y!8,(5#
=(R3-['QIb
<?xml version="1.0"?> i$.! 8AV6
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ]l=CiG4!M
r0OP !u
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4"nYxL"<4
71IM`eL=ED
1.0.dtd"> ^IvQdVB
0<<ATw$aQ
<xwork> 9%Vy,
%<|<%~l&
<package name="user" extends="webwork- c[3x>f0
klc$n07
interceptors"> L[5U(`q[
'aeuL1mz
<!-- The default interceptor stack name P~&J@8)c
Aj/EaIq
--> ;B }4pv}
<default-interceptor-ref lN"@5(5%
-`X`Ff
name="myDefaultWebStack"/> V<}chLd,
I!lR 7%
<action name="listUser" M`9|8f,!a
|<8Fa%!HHc
class="com.adt.action.user.ListUser"> VV[Fb9W ;
<param *6}'bdQbNP
fG8^ |:
name="page.everyPage">10</param> -) +B!"1
<result }t|i1{%_
g&_f%hx?
name="success">/user/user_list.jsp</result> xMpgXB!'
</action> 4qd(a)NdY
y\9#"=+
</package> E
KJ2P$
hoiC
J}us
</xwork> Hkf]=kPy*
@bAuR
E8lq2r=
F[B=sI
p9MJa[}V
'!MKZKer
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 s gZlk9x!Q
#*S.26P^4
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。 k|jr+hmn":
tQ.H/;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 kf95 )iLo
ExFz@6@
"d0D8B7HI@
|WT]s B0Eq
[CAFh:o
我写的一个用于分页的类,用了泛型了,hoho xNRMI!yv
`O%O[
java代码: L@?3E`4/v
V1Gnr~GM
T}"[f/:N/
package com.intokr.util; Nn?$}g
ZP0D)@8
import java.util.List; Bq-}BN?pz
V8pZr+AJ
/** MlbcJo3
* 用于分页的类<br> @W, <8
* 可以用于传递查询的结果也可以用于传送查询的参数<br> <<Z, 1{3F
* iMV=R2t 2
* @version 0.01 :N_DJ51
* @author cheng 7e#|Iq:o
*/ C/9]TkX}q
public class Paginator<E> { CZ{7?:^f
privateint count = 0; // 总记录数 [e{W:7uFV
privateint p = 1; // 页编号 u&o$2
'8
privateint num = 20; // 每页的记录数 {([`[7B>a<
privateList<E> results = null; // 结果 <33,0."K
mO8/eVws[M
/** o?IrDQ2gmh
* 结果总数 Czy}~;_Ay
*/ yGV>22vv
M
publicint getCount(){ gr@Ril^
return count; I;G(Wj
} j^hLn>
0fqycGSmU
publicvoid setCount(int count){ 'C>sYSL
this.count = count; V&Rwj_Y
} {/,AMJ<:G]
_~F
0i?
/** =)w#?DGpj
* 本结果所在的页码,从1开始 wAL}c(EHO
* #veV {,g
* @return Returns the pageNo. p|BoEITL
*/ %E [HMq<H
publicint getP(){ U: )Gc
return p; k7cY^&o
} W u$yB!
V"} Jsr
/** BP\6N%HC%&
* if(p<=0) p=1 _w'_l>I
* !*?9n^PaF
* @param p K(WKx7Kky^
*/ vF[ 4kDHk
publicvoid setP(int p){ 8f65;lyN
if(p <= 0) OF-VVIS
p = 1; y3PrLBTz
this.p = p; {9^p3Q+:P
} q)AX*T+
0y+i?y
9
/** A<( DYd1H
* 每页记录数量 Ea-U+7JC
*/ Qam48XZ >
publicint getNum(){ H4sc7-
return num; "I9 r>=
} hMV>5Y[s
dT (i*E\j
/** f"zmN G'
* if(num<1) num=1 ,g,Hb\_R)
*/ K{B|
publicvoid setNum(int num){ V\l@_%D[(v
if(num < 1) `82Dm!V
num = 1; Wu8^Z Z{
this.num = num; ]e+&Pxw]e
} Q7tvpU
6GqC]rd*:
/** /{W6]6^
* 获得总页数 TNK1E
*/ 3=*ur( Qy
publicint getPageNum(){ N0JdU4'
return(count - 1) / num + 1;
`46.!
} GJs~aRiz
@YG-LEh
/** h ^s8LE3
* 获得本页的开始编号,为 (p-1)*num+1 JO90TP
$
*/ I`i"*z
publicint getStart(){ t*u#4I1
return(p - 1) * num + 1; }Gy M<!:
} aUA)p}/:
_aJKt3GQ
/** gFTlP
* @return Returns the results. =q`T|9v
*/ 5}Xi`'g,
publicList<E> getResults(){ 7?y7fwER
return results; HPJHA ,
} LIQ].VxIs
Zj1bG{G=i
public void setResults(List<E> results){ 5Z6MQ`(k
this.results = results; YhqMTOw
} gx?r8
_mwt{D2r}
public String toString(){ Vo6g /h?`
StringBuilder buff = new StringBuilder n\f]?B(
9\/oL{
(); qPN9Put
buff.append("{"); )feZ&G]
buff.append("count:").append(count); n=AcN
buff.append(",p:").append(p); 2i1xSKRYrD
buff.append(",nump:").append(num); &ODo7@v`1
buff.append(",results:").append bSz7?NAp
$$"G1<EZ
(results); +%u3% }
buff.append("}"); =9,^Tu|
return buff.toString(); FouN}X6
} het<#3Bo
N-Z=p)]
} _{gqi$Mi
2gMG7%d
!6@ 'H4cb=