Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 J5Ovj,[EZ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +=M N_
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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 f Hd|tl
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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 @s.civ!Yk
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分页支持类: s
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java代码: w<&R|= 93
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package com.javaeye.common.util; ?
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import java.util.List; Y?v{V>;*A
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publicclass PaginationSupport { 0PD=/fh[
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publicfinalstaticint PAGESIZE = 30; JnIE6@g<y
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privateint pageSize = PAGESIZE; e|}B;<
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privateList items; Fs(FI\^
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privateint totalCount; ^D8~s; ?
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privateint[] indexes = newint[0]; 8+@j %l j
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privateint startIndex = 0; 8I[=iU7]l
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public PaginationSupport(List items, int `?G&w.Vs
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totalCount){ 19b@QgfWpb
setPageSize(PAGESIZE); V}X>~ '%
setTotalCount(totalCount); H<9_BA?
setItems(items); r yNe=9p
setStartIndex(0); v>0I=ut
} H1.ktG
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public PaginationSupport(List items, int _9C,N2a{C
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totalCount, int startIndex){ _#K?yP?
setPageSize(PAGESIZE); C#LTF-$])
setTotalCount(totalCount); />n!2'!
setItems(items); k8c(|/7d
setStartIndex(startIndex); o~7D=d?R
} Rt>mAU$}
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public PaginationSupport(List items, int +rJDDIb
#>M^BOR8
totalCount, int pageSize, int startIndex){ K7X*N
setPageSize(pageSize); [/o BjiBA
setTotalCount(totalCount); {T-=&%||
setItems(items); &=]!8z=
setStartIndex(startIndex); ~)pso7^:
} H<3:1*E
l
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publicList getItems(){ UD=[::##
return items; <JIqkGeAi
} : T{VCw:*
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publicvoid setItems(List items){ >n3ig~0d
this.items = items; ,FwpHs $A
} fV2w &:^3
EU7nS3K)O~
publicint getPageSize(){ +Sc2'z>R
return pageSize; zZ,"HY=jN
} .k$Yleg
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publicvoid setPageSize(int pageSize){ cJf&R^[T
this.pageSize = pageSize; 0V?7'Em
} orOq5?3
eA*We
publicint getTotalCount(){ fA"c9(>m%]
return totalCount; 7K ~)7U
} w
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publicvoid setTotalCount(int totalCount){ 31\mF\{V
if(totalCount > 0){ V-3;7
this.totalCount = totalCount; eLLOE)x
int count = totalCount / BiDyr
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pageSize; lL'Bop@
if(totalCount % pageSize > 0) +:W/=C
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count++; $4*gi&
indexes = newint[count]; M3Qi]jO98
for(int i = 0; i < count; i++){ |qVM`,%L
indexes = pageSize * u{7->[=
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i; "!_vQ^y
} !1%Sf.`!_
}else{ ?9%$g?3Z
this.totalCount = 0; X#Ob^E%J
} V CVKh
} %g^:0me`
}t:*w
publicint[] getIndexes(){ ]TJ258P}
return indexes; 1;PI%++
} f'bwtjO
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publicvoid setIndexes(int[] indexes){ rp^:{6O
this.indexes = indexes; re,}}'
} 4T$DQK@e
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publicint getStartIndex(){ _Fn`G.r<
return startIndex; W7;RQ
} Al]*iw{
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publicvoid setStartIndex(int startIndex){ c$lZ\r"
if(totalCount <= 0) mN>(n+ly
this.startIndex = 0; Yg}b%u,Q
elseif(startIndex >= totalCount) %%#bTyF
this.startIndex = indexes ta<8~n^?
+z0s)HU>j
[indexes.length - 1]; 2R
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elseif(startIndex < 0) _0ZU I^#
this.startIndex = 0; oIQ$98 M
else{ K"hnGYt?
this.startIndex = indexes 4'tY1d
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[startIndex / pageSize]; p>f?Rw_
} I0><IaFy
} 3[m2F O,Z
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publicint getNextIndex(){ ggrkj0
int nextIndex = getStartIndex() + $e{[fmx
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pageSize; p$ETAvD
if(nextIndex >= totalCount) j/F('r~L
return getStartIndex(); Z$r7Hi
else ur7S
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return nextIndex; jP0TyhM
} eKLE^`2*@
u#`51Hr$
publicint getPreviousIndex(){ <>Ha<4A
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int previousIndex = getStartIndex() - 6!USSipn
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pageSize; ^.
if(previousIndex < 0) O4:_c-V2
return0; )]LP8
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else /{P-WRz>
return previousIndex; ep0dT3&
} <r(D\rmD
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} (9=E5n6o
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VS!v7-_N5
抽象业务类 I~Qi):&x
java代码: Rlm28
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/** {t.S_|IE
* Created on 2005-7-12 (uy\~Zb
*/ [0]J
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package com.javaeye.common.business; 'm"Ez'sS
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import java.io.Serializable; VR%*8=
import java.util.List; ,rF!o_7
ITEf Q@#jU
import org.hibernate.Criteria; =fdW H4
import org.hibernate.HibernateException; s?&S<k-=fr
import org.hibernate.Session; Xy`'h5
import org.hibernate.criterion.DetachedCriteria; [d-Y1
import org.hibernate.criterion.Projections; g:!R't?
import e\f\CMb
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org.springframework.orm.hibernate3.HibernateCallback; GXNkl?#
import Sfp-ns32%A
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org.springframework.orm.hibernate3.support.HibernateDaoS XW\
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upport; +(z[8BJl
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import com.javaeye.common.util.PaginationSupport; 2- (}=N
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public abstract class AbstractManager extends k,; (`L
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HibernateDaoSupport { "3|OB, <;:
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privateboolean cacheQueries = false; ~*+evAP
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privateString queryCacheRegion; q_L. Sy|)
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publicvoid setCacheQueries(boolean i70\`6*;B
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cacheQueries){ -^;,m=4{3
this.cacheQueries = cacheQueries;
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} )q\6pO@
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publicvoid setQueryCacheRegion(String J4z&J SY
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queryCacheRegion){ }<w9Jfr"X
this.queryCacheRegion = %qqeL
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queryCacheRegion; ,^<39ng
} {ot6ssT=D
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publicvoid save(finalObject entity){ ,S@B[+VZ
getHibernateTemplate().save(entity); V?`|Ha}
} <]|!quY<*
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publicvoid persist(finalObject entity){ _\=
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getHibernateTemplate().save(entity); qK~]au:C
} |z&7KoYK'
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publicvoid update(finalObject entity){ b^()[4M;
getHibernateTemplate().update(entity); `0w!&
} BQeg-M
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publicvoid delete(finalObject entity){ #J8(*!I
getHibernateTemplate().delete(entity); jqTK7b
} ">S1,rhgS
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publicObject load(finalClass entity, ]"YXa~b
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finalSerializable id){ oz[G'[\}F
return getHibernateTemplate().load bxBndxl
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(entity, id); E8<,j})*
} H`Zg-j`
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publicObject get(finalClass entity, MBU4Awj
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finalSerializable id){ h uR ^l
return getHibernateTemplate().get q./jYe
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(entity, id); hewc5vrL
} P=9UK`n
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publicList findAll(finalClass entity){ knb0_nA
return getHibernateTemplate().find("from "-AFWWKtx
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" + entity.getName()); :b_hF
} pL> Yx>
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publicList findByNamedQuery(finalString jYBiC DD
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namedQuery){ ?[WUix;
return getHibernateTemplate 6@FxPi9|#
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().findByNamedQuery(namedQuery); O0bOv S
} ra_TN;(
wsc=6/#u
publicList findByNamedQuery(finalString query, AUfcf*
[;'$y:L=g
finalObject parameter){ +>c%I&h}`
return getHibernateTemplate +#A~O4%t
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().findByNamedQuery(query, parameter); (OavgJ+Y
} Eq=JmO'gHs
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publicList findByNamedQuery(finalString query, qDfhR`1k
Z *v`kl
finalObject[] parameters){ %N\8!aXnf
return getHibernateTemplate ) :Px`] 5
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().findByNamedQuery(query, parameters); L&]{GNw
} yLl:G;
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publicList find(finalString query){ tn(6T^u
return getHibernateTemplate().find :x^e T
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(query); ?[DVYP
} N
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publicList find(finalString query, finalObject 1$:O9{F
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parameter){ c{x:'@%/s'
return getHibernateTemplate().find -KG1"g,2
gh `_{l
(query, parameter); 77]lpmC
} tZ*>S]qD
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public PaginationSupport findPageByCriteria "tDB[?
1&Mpx!K*T
(final DetachedCriteria detachedCriteria){ 58`Dcx,yJ
return findPageByCriteria wARd^Iw
Kv#Q$$)r
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3J3wKw!`
} 5B3sRF}
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public PaginationSupport findPageByCriteria 8hSw4S"$
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(final DetachedCriteria detachedCriteria, finalint ws
U @hqS
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startIndex){ *w6F0>u
return findPageByCriteria o+- 0`!yj
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(detachedCriteria, PaginationSupport.PAGESIZE, IL?"g{w
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startIndex); muhu`
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} -f?,%6(1
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public PaginationSupport findPageByCriteria lt\Bm<"z!1
5)->.* G*
(final DetachedCriteria detachedCriteria, finalint @Q!Tvw/
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pageSize, ="AaC!E,W
finalint startIndex){ )L_@l5l
return(PaginationSupport) tQTjqy{K
#;;A~d:V
getHibernateTemplate().execute(new HibernateCallback(){ I-Am9\
publicObject doInHibernate w.+G+r=
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(Session session)throws HibernateException { a?X@ D<.;
Criteria criteria = v[jg|s&6"
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detachedCriteria.getExecutableCriteria(session); BJp~/H`vd
int totalCount = %P C[-(Q
r=]$>&
((Integer) criteria.setProjection(Projections.rowCount L;6{0b58$
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()).uniqueResult()).intValue(); A3J=,aRI_v
criteria.setProjection )vY )Mg
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(null); UH((d*HX4
List items = i
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criteria.setFirstResult(startIndex).setMaxResults FB3}M)G>M
bH%d*
(pageSize).list(); {.Brh"yC
PaginationSupport ps = DIkf#}
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new PaginationSupport(items, totalCount, pageSize, on1B~?*D
*{O[}
startIndex); tNYuuC%N
return ps; B!4~A{
}
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}, true); 4lwoTGVZj
} 0L d"df*
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public List findAllByCriteria(final *0_Q0SeE,o
(Dx p
DetachedCriteria detachedCriteria){ #W4
" ^#2
return(List) getHibernateTemplate T5dnj&N ]
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().execute(new HibernateCallback(){ ]UGk"s5A
publicObject doInHibernate h1$75E?,
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(Session session)throws HibernateException { 3MDs?qx>s
Criteria criteria = u7},+E)+B
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detachedCriteria.getExecutableCriteria(session); YU\k D
return criteria.list(); $M$-c{>s
} I2,AT+O<
}, true); vz&88jt
} x]IJ;
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public int getCountByCriteria(final zu
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DetachedCriteria detachedCriteria){ eAjsMED
Integer count = (Integer) /E:BEm!
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getHibernateTemplate().execute(new HibernateCallback(){ y<c7RK]
publicObject doInHibernate 3`Xzp
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(Session session)throws HibernateException { COHook(:
Criteria criteria = MHA_b^7?
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detachedCriteria.getExecutableCriteria(session); dfh 1^Go
return d-z[=1m
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criteria.setProjection(Projections.rowCount gJ^taUE
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()).uniqueResult(); SF da?>
} F
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}, true); W>'(MB$3
return count.intValue(); _ER. AKY
} $weC '-n@
} x0lAJaG
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用户在web层构造查询条件detachedCriteria,和可选的 F3L+X5D.yu
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 :#D~j]pP
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PaginationSupport的实例ps。 R\]C;@J<
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ps.getItems()得到已分页好的结果集 ~
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ps.getIndexes()得到分页索引的数组 Mh{>#Gs
ps.getTotalCount()得到总结果数 Eqh*"hE7
ps.getStartIndex()当前分页索引 k *>"@
ps.getNextIndex()下一页索引 <,X=M6$0n
ps.getPreviousIndex()上一页索引 +=sw&DH
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 wJ"]H!r0
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 <j3|Mh_(I
eHR]qy 0_X
一下代码重构了。 v8n^~=SH
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我把原本我的做法也提供出来供大家讨论吧: }$
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首先,为了实现分页查询,我封装了一个Page类: @uanej0q7
java代码: =|2F?
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/*Created on 2005-4-14*/ ) $0>L5d:
package org.flyware.util.page; mu5r4W47
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/** hDQk zqW
* @author Joa i1'G_bo4F7
* |sEuhP\A3
*/ Ijk hV
publicclass Page { #%w)w R3
#Tt*NU
/** imply if the page has previous page */ uBxoMxWm
privateboolean hasPrePage; h4+*ssnYV
%0Qq~J@Lu
/** imply if the page has next page */ c2?VjuB0
privateboolean hasNextPage; Kmw #Q`
.Lu3LVS
/** the number of every page */ &I%E8E
privateint everyPage; CxSh.$l
/)`]p1c1%w
/** the total page number */ NEvNj
privateint totalPage; 9hh~u
-8L
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/** the number of current page */ xW2?\em
privateint currentPage; '+3C2!
B2|0.G|[j
/** the begin index of the records by the current X{<taD2~
X*:,|
query */ E0yx
@Vx
privateint beginIndex; :,g]Om^
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/** The default constructor */ \Hf/8!q
public Page(){ `uZMln @
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} Tu5p`p3-j
+S`cUn7
/** construct the page by everyPage L./c#b!{
* @param everyPage M'F<1(
* */ Uw!d;YQm
public Page(int everyPage){ Y=g]\%-PB
this.everyPage = everyPage; 7upWM~H^
} yz5! >|EB
pLys%1hg
/** The whole constructor */
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public Page(boolean hasPrePage, boolean hasNextPage, nh"dPE7^
E.+%b;Eqe
gVI`&W__,
int everyPage, int totalPage, ~*9Ue@
int currentPage, int beginIndex){
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this.hasPrePage = hasPrePage; &Yc'X+'4
this.hasNextPage = hasNextPage; es~1@Jb
this.everyPage = everyPage; 0L1sF'ZN
this.totalPage = totalPage; ST0TWE'
this.currentPage = currentPage; @65xn)CD{
this.beginIndex = beginIndex; &%;n9K
} s9OW.i]zX
O:GAS [O`
/** os&FrtDg
* @return /oLY\>pD
* Returns the beginIndex. e+D]9wM8
*/ IV1Y+Z )
publicint getBeginIndex(){ Dln1 R[
return beginIndex; c!'\k,ma<9
} SynRi/BRmw
3HW&\:q5'M
/** DHv86TvJt
* @param beginIndex >(wQx05^D
* The beginIndex to set. S^|U"
*/ dv+ZxP%g
publicvoid setBeginIndex(int beginIndex){ DdUw~n,
this.beginIndex = beginIndex; VaGQre
} IkjJqz
6x=w-32+ y
/** .Eb]}8/}E
* @return k_ywwkG9lU
* Returns the currentPage. Cb`, N
*/ ~G-W|>
publicint getCurrentPage(){ \nPf\6;M
return currentPage; ! K_<hNG&
} q-ko)]
he:z9EG}
/** cofdDHXfQI
* @param currentPage S' kgpF"bm
* The currentPage to set. kS=nH9
*/ dUt4]
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publicvoid setCurrentPage(int currentPage){ 5E1`qof
this.currentPage = currentPage; -mn/Yv
} N)AlQ'Lwx
h]+;"v6 /
/** LHXR7Fjc
* @return zy nX9t
* Returns the everyPage. vt^7:!r
*/ sQ,xTWdj
publicint getEveryPage(){ LExm#T`
return everyPage; o 9/,@Ri\5
} x[Hx.G}5+
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/** <\O8D0.d
* @param everyPage <hiv8/)?
* The everyPage to set. BRskxyL&,
*/ ;1{=t!z=
publicvoid setEveryPage(int everyPage){ :z&kbG
this.everyPage = everyPage; 5u;//Cm
} 9==4T$nM[
@ =~k[o
/** .`5|NUhN
* @return l>`66~+s,`
* Returns the hasNextPage. }^$1<GT
*/ O(!;7v}
publicboolean getHasNextPage(){ oz)4YBf
return hasNextPage; VltM{-k^
} v}a{nU'
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/** &rD8ng+$
* @param hasNextPage sQkijo.
* The hasNextPage to set. s-+-?$K
*/ !<HMMf,-D
publicvoid setHasNextPage(boolean hasNextPage){ )lJAMZ 5xp
this.hasNextPage = hasNextPage; 6 U[VoUU
} X[1D$1Dvw
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/** Z`MpH
* @return SA&(%f1d
* Returns the hasPrePage. 3S]QIZ1
*/ /|i*'6*
publicboolean getHasPrePage(){ fCF.P"{W"
return hasPrePage; $fT5Vc]B4
} AWx@Z7\z"g
F[yofRN
/** <!XunXh
* @param hasPrePage #$-?[c$>
* The hasPrePage to set. 4g8o~JI:v
*/ @6tczU}ak
publicvoid setHasPrePage(boolean hasPrePage){ ;-@: }/
this.hasPrePage = hasPrePage; 0XCAnMVo
} ?%qaoxG37
s(5hFuyg
/** ;CF:cH*
* @return Returns the totalPage. 'N+;{8C-{
* :{iH(ae;
*/ n7K%lj-.P
publicint getTotalPage(){ Q\
6-SAS
return totalPage; N>"L2E=z$|
} K Cw
jX8)Ov5Mv
/** ![\P/1p
* @param totalPage %_4#WI
* The totalPage to set. F0z7".)
*/ ?O#,{ZZf=
publicvoid setTotalPage(int totalPage){ amC)t8L?
this.totalPage = totalPage; Nc{&AV8Y_v
} H1B%}G*Ir-
8tQL$CbO
} <nD@4J-A0
zEtsMU
=FV(m
S
[r8[lkR
Xm>zT'B_tJ
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 YW&K,)L@
dhLR#m30T
个PageUtil,负责对Page对象进行构造: e1h7~ j
java代码: lGWz
U'(zKqC
zQ{bMj<S
/*Created on 2005-4-14*/ eS@j? Y0y
package org.flyware.util.page; M.}J SDt
+
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import org.apache.commons.logging.Log; *->*p35
import org.apache.commons.logging.LogFactory; {cOx0=
ou~$XZ7oi
/** K;sC#9m
* @author Joa S sW<,T
* @9_mk@
*/ 0>td[f
publicclass PageUtil { F%o!+%&7
4jTO:aPh_
privatestaticfinal Log logger = LogFactory.getLog 3lZl
'q$ Ym0nL
(PageUtil.class); .#SgU<Wq
6d;}mhH
/** YCltS!k
* Use the origin page to create a new page XK3O,XM
* @param page ^O@eyP
* @param totalRecords oj Y.6w
* @return #UL75
*/ 9GCK3
publicstatic Page createPage(Page page, int xcWR#z{z
lqmQQ*Z
totalRecords){ v9*+@
return createPage(page.getEveryPage(), ZM -P
:2S?|7U4
page.getCurrentPage(), totalRecords); JFX}))7
} bS~Y_]B
b:hta\%/2
/** dLb$3!3
* the basic page utils not including exception R3_OCM_*
C/Z#NP~ *
handler jGz~}&B
* @param everyPage }vU/]0@,E
* @param currentPage oJQS&3;/r
* @param totalRecords TY %zw6 #p
* @return page 5wx~QV=Hh
*/ "0jwCX
Cu
publicstatic Page createPage(int everyPage, int ^`id/
uBt
]4d*
currentPage, int totalRecords){ r1-MO`6
everyPage = getEveryPage(everyPage); n5UUoBv
currentPage = getCurrentPage(currentPage); ^Z9bA( w8
int beginIndex = getBeginIndex(everyPage, Lr:n
Ly8=SIZ
currentPage); bHRn}K+<}c
int totalPage = getTotalPage(everyPage, 0~RD@>]
L5`k3ap|
totalRecords); K 'l-6JY-
boolean hasNextPage = hasNextPage(currentPage, uGC5XX^
.uauSx/#4
totalPage); }g-w[w 7p
boolean hasPrePage = hasPrePage(currentPage); NN'pBUR
|\uj(|
returnnew Page(hasPrePage, hasNextPage, %M1l[\N
everyPage, totalPage, K)>F03=uE
currentPage, 0{
mm%@o
NO[A00m|OL
beginIndex); +&VY6(Zj+*
} iE"]S )
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privatestaticint getEveryPage(int everyPage){ &nr{-][
return everyPage == 0 ? 10 : everyPage; "y"oV[`
} &Hp*A^M
GIEQD$vy
privatestaticint getCurrentPage(int currentPage){ ed',\+.uB
return currentPage == 0 ? 1 : currentPage; B2]52Fg-"
} DKfpap}8u
IKP_%R8.
privatestaticint getBeginIndex(int everyPage, int qqZ4K:oC,
k-n`R)p:
currentPage){ @br)m](@
return(currentPage - 1) * everyPage; eEVB
} '9WTz(0?
Izu____
privatestaticint getTotalPage(int everyPage, int GNv{Ij<
lBFKfLp&
totalRecords){ q>BJ:_I
i
int totalPage = 0; r&a}U6k(y
59 g//;35@
if(totalRecords % everyPage == 0) H ;=^
W
totalPage = totalRecords / everyPage; 0~BaQ,
A@
else h.#:7d(g
totalPage = totalRecords / everyPage + 1 ; :$K=LV#Iru
0`7yPq*
return totalPage; z4BU}`;b3t
} MnFrQC
2#5Q~
privatestaticboolean hasPrePage(int currentPage){ s(Gs?6}>T
return currentPage == 1 ? false : true; d'MZ%.#
} QObVJg,GD
bR"4:b>K
privatestaticboolean hasNextPage(int currentPage, G?Gf,{#K
kJuG haO
int totalPage){ dpq(=s`s
return currentPage == totalPage || totalPage == Q`8-|(ngw
BZ.l[LMp
0 ? false : true; wg0_J<y]
} 4_VgJ9@
S>T ;`,
#n+u>x.O
} iYT?6Y|+
_ s}aF
vS~tr sI
LWqKSNE;
D>{`I'
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。 f:\)!
&W
[n/c7Pe
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 v=G*K11@
dh6kj-^;Cf
做法如下: &AxtSIpucP
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >>J$`0kM*
{,Vvm*L/
的信息,和一个结果集List: Co nik`
java代码: sS{Co8EJn
x#SE%j?
\e4AxLP
/*Created on 2005-6-13*/ }U'9 d#N
package com.adt.bo; Mn&_R{{=
!l#aq\:}~e
import java.util.List; p+?`ru
;Ngk"5
import org.flyware.util.page.Page; OHAU@*[lM
S+.>{0!S"
/** iNkN'("
* @author Joa bnkZWw'9
*/ *FEJ5x
publicclass Result { N}nE9z5
y7h^_D+Ce
private Page page; CB>W# P%
q M_c-^F
private List content; *ezMS
L;*7p9
/** %-fXa2
* The default constructor Xe&9|M
*/ yI|x
5f
public Result(){ F;`c0ja]
super(); 8 0nu^_
} {9 |*au(K
A405igF
/** #9}1Lo>
* The constructor using fields ML|?H1m>
* *A48shfO
* @param page o<lmU8xB=
* @param content qY%|Uo
*/ i^:#*Q-co
public Result(Page page, List content){ V /\Y(Mxc
this.page = page; 4|%Y09"lv
this.content = content; q90RTX'CY
} <L8FI78[*
"@VYJ7.1
/** 6FUcg40Y
* @return Returns the content. AfO.D?4x
*/ T.z efoZ
publicList getContent(){ 0OG
3#pE
return content; Pw]+6
} F|+B8&-v
_nz_.w0H9
/** 6`'g ${U
* @return Returns the page. ua=7YG
*/ (FGy"o%TP'
public Page getPage(){ H1?C:R
return page; &Hf%Va[B
} 'W9[Vm
m#[c]v{
/** LrO[l0#'Q
* @param content B+Qo{-
* The content to set. X6B,Mply
*/ JT<JS6vw#
public void setContent(List content){ uAnL`
this.content = content; sF :pwI5^
} g2?W@/pa
HhCFAq"j
/** bYQ@!
* @param page w#a`k9y
* The page to set. )O*h79t^Q
*/ d,i4WKp
publicvoid setPage(Page page){ F
]D^e{y
this.page = page; 4IOqSB|
} &.2%p
} P}Mu|AEG
i4> M
dzbbFvG
yMkR)HY
80%"2kG
2. 编写业务逻辑接口,并实现它(UserManager, lz>.mXdx
a 01s'9Be
UserManagerImpl) R86i2',
java代码: nt&%
sM-X
!a V:T&6
dj] O
/*Created on 2005-7-15*/ 6IK>v*<
package com.adt.service; &
\5Ur^t
:rufnmsP<U
import net.sf.hibernate.HibernateException; 4Hyp]07
p;o "i_!
import org.flyware.util.page.Page; mV"F<G; H
]YZ_kc^(V;
import com.adt.bo.Result; F&7Z(
e 5(|9*t
/** 'Q]Wk75
* @author Joa O:,Gmft+
*/ ~3Qa-s;g
publicinterface UserManager { $u,A/7\s
=kq<J-:#R
public Result listUser(Page page)throws TL"+Iv2]/$
D=D.s)ns*
HibernateException; $@^\zg1n
T$FKn
} Oel%lY}m3
lxD~l#)^ln
_E0yzkS
9.~_swkv
`T%nGV l>\
java代码: F|VHr@%
k&K'FaM!
tycVcr\(
/*Created on 2005-7-15*/ ESIeZhXVH
package com.adt.service.impl; B\=T_'E&
WT,dTn;W
import java.util.List; 6P(jc
l%i*.b(
import net.sf.hibernate.HibernateException; ?a,`{1m0\
?)Gb=
import org.flyware.util.page.Page; $i3`cX)g
import org.flyware.util.page.PageUtil; 9w0v?%%_
p@DVy2,EY
import com.adt.bo.Result; )`|`PB
import com.adt.dao.UserDAO; BdvpG
import com.adt.exception.ObjectNotFoundException; K-.%1d@$y
import com.adt.service.UserManager; vgNrHq&2q
`5x0p a
/** 8ce'G"
b
* @author Joa \:JY[s/
*/ mH<|.7~0
publicclass UserManagerImpl implements UserManager { 4/SltWU
@YS,)U)4S
private UserDAO userDAO; Ka)aBU9
-0CL#RzKR
/** 7oL:C
* @param userDAO The userDAO to set. :<
]sJfN
*/ a9 S&n5
publicvoid setUserDAO(UserDAO userDAO){ 51AA,"2[_
this.userDAO = userDAO; `'(@"-L:7
} D iHj!tZN
&d!ASa
/* (non-Javadoc) ]P^3uXi
* @see com.adt.service.UserManager#listUser 8JMxA2tZhG
fo9V&NE
(org.flyware.util.page.Page) "x:-#2+h
*/ 8_rd1:t5
public Result listUser(Page page)throws B.b sU
c~\^C_
HibernateException, ObjectNotFoundException { [>Zg6q|
int totalRecords = userDAO.getUserCount(); ay{]Vqi9
if(totalRecords == 0) 54s90
throw new ObjectNotFoundException ~(rZ)
>k}Kf1I
("userNotExist"); & )-fC
page = PageUtil.createPage(page, totalRecords); !.q#X^@>L
List users = userDAO.getUserByPage(page); 8-O:e
returnnew Result(page, users); 3)^2X
} 7{rRQ~s&g9
5VN~?#K
} >;xkiO>Y
s2+_`Ogg
${t$:0R,h
]jmZ5h#[
WL\*g] K4
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 yS#D$q2_
[#:yOZt
询,接下来编写UserDAO的代码: V<n#%!M5gV
3. UserDAO 和 UserDAOImpl: jlD3SF~2
java代码: ; ?,'jI*1
yzGBGC
Zc9S[ivq
/*Created on 2005-7-15*/ EY :EpVin
package com.adt.dao; Pn}oSCo
Qeq=4Nq
import java.util.List; <z
wI@i
y<yU5
import org.flyware.util.page.Page; /w*HxtwFmD
;Qlb].td
import net.sf.hibernate.HibernateException; 0}Qd
Ei@al>.\
/** s*>B"#En
* @author Joa /cD]m
*/ Vgj[m4l
publicinterface UserDAO extends BaseDAO { g*%o%Lv
QP6a,^];
publicList getUserByName(String name)throws A1jA$
d\ Xijy
HibernateException; BQ!_i*14+
Xpmi(~n
publicint getUserCount()throws HibernateException; #W L>ha
v
**n109R
publicList getUserByPage(Page page)throws M;0\fUh;
,fs>+]UY3
HibernateException; hl+
T
f[$Z<:D-ve
} <QK2Wc_}-"
+|O&k
.YIb ny1
SYv5{bff =
rf2-owWN
java代码: 4?7OP
t6
xC$CRzAe5p
kx[h41|n
/*Created on 2005-7-15*/ 9q<?xO
package com.adt.dao.impl; kQtnT7
be&,V_F
import java.util.List; pW2-RHGJY
@|7e~U
import org.flyware.util.page.Page; S#Pni}JD
&PEw8: TX
import net.sf.hibernate.HibernateException; y]%Io]!d
import net.sf.hibernate.Query; 0 ^ $6U
`S/;S<';
import com.adt.dao.UserDAO; TSP#.QY
fh}j)*K8
/** +q~dS.
* @author Joa &qeMYYY
*/ GEfTs[
public class UserDAOImpl extends BaseDAOHibernateImpl iD!]I$
^@xn 3zJ
implements UserDAO { <o_(,,P%
JwmH_nJ(
/* (non-Javadoc) :]IYw!_-p
* @see com.adt.dao.UserDAO#getUserByName m[?gN&%nc
Y[alOJ
(java.lang.String) gA DF
*/ ~YrO>H` B
publicList getUserByName(String name)throws O8w|!$Q.
j}@n`[V1
HibernateException { UxVxnJ_
String querySentence = "FROM user in class {o.i\"x;
| <l=i(
com.adt.po.User WHERE user.name=:name"; Ceak8#|4
Query query = getSession().createQuery >[gNQJ6
Q|:qs\6q5
(querySentence); [e`6gGO
query.setParameter("name", name); o51jw(wO
return query.list(); x]jJ
} 6
VuMx7W1
.t|B6n!
/* (non-Javadoc) y[sO0u\
* @see com.adt.dao.UserDAO#getUserCount() %C(^v)"
*/ 0N>R!
publicint getUserCount()throws HibernateException { y8=H+Y
int count = 0; XSz)$9~hk
String querySentence = "SELECT count(*) FROM =LMM]'no,
T0P_&E@X
user in class com.adt.po.User"; \#)w$O
Query query = getSession().createQuery $/;;}|hqi
L)j<;{J/Q0
(querySentence); IH~[/qNk
count = ((Integer)query.iterate().next $|bdeQPr\
\ POQeZ
()).intValue(); <;nhb
return count; H)l7:a
} `%S#XJU
@a}jnl(2
/* (non-Javadoc) |jE0H!j
* @see com.adt.dao.UserDAO#getUserByPage %.VFj7J
:f5"w+
(org.flyware.util.page.Page) 0Wc8\c
*/ _mn2bc9M
publicList getUserByPage(Page page)throws C{8(ew
/L? ia
HibernateException { :LEC[</yvl
String querySentence = "FROM user in class lcYjwA
ky-9I<Z,,
com.adt.po.User"; dw]jF=u
Query query = getSession().createQuery %T'<vw0
i-*ZW:
(querySentence); s+OXT4>+
query.setFirstResult(page.getBeginIndex()) 8[xl3=
.setMaxResults(page.getEveryPage()); b;%>?U`>p
return query.list(); ,c9K]>8m`
} ]KE"|}B
mJ L=H
} n(tx'&U"R
Y]6kA5
s'JbG&T[J
j0+l-]F-
6@;
P
至此,一个完整的分页程序完成。前台的只需要调用 #[.aj2
c}r"O8M
userManager.listUser(page)即可得到一个Page对象和结果集对象 _?QVc0S!
)7s(]~z
的综合体,而传入的参数page对象则可以由前台传入,如果用 k~=_]sLn
,37\8y?o\
webwork,甚至可以直接在配置文件中指定。 K)[DA*W
qaZQ1<e
下面给出一个webwork调用示例: ;fGh]i
java代码: XlDN)b5v{
FEwPLViso
;"Q.c#pA$g
/*Created on 2005-6-17*/ N(=Z4Nk5
package com.adt.action.user; @[. 0,
N>Q~WXvV#
import java.util.List; JOFQyhY0>m
g?i0WS
import org.apache.commons.logging.Log; -b$m<\0*
import org.apache.commons.logging.LogFactory; -#<AbT
import org.flyware.util.page.Page; ee\QK,QV
JsD|igqF-
import com.adt.bo.Result; AMf{E
import com.adt.service.UserService; mfCp@1;26
import com.opensymphony.xwork.Action; e-Ma8+X\
%"CF-K@th
/** f'?FYBL
* @author Joa _-5| "oJ
*/ Vc*"Q8aZ~
publicclass ListUser implementsAction{ OH/!Ky\@
"cD MFu
privatestaticfinal Log logger = LogFactory.getLog >&%#`PKT
VtnVl`/]
(ListUser.class); c%@<
h6
]wm<$+@
private UserService userService; }NpN<C+
5-?*Boi>i
private Page page; Ev>P|kV&A
PQJw"[N/YM
privateList users; @P@{%I
1'4?}0Dok
/* {u)>W@Lr
* (non-Javadoc) s&7TARd
* DrA\-G_7
* @see com.opensymphony.xwork.Action#execute() *!m(oP
*/ +*L<"@
publicString execute()throwsException{ 7 F> a&r
Result result = userService.listUser(page); i#bcjH
page = result.getPage(); r%\%tz'`j
users = result.getContent(); p!>DA?vF
return SUCCESS; x|`BF%e/v
} 9oQ$w?=#$
CWY-}M
/** fR>"d<;T
* @return Returns the page. Tnoy#w}Ve
*/ !q!5D`
public Page getPage(){ .OcI.1H [
return page; z07Xj%zX9
} ^?5HagA
ToR@XL!%rP
/** 7!/!a*zg
* @return Returns the users. 10IX84
*/ \=uD)9V
publicList getUsers(){ 08G${@D+X0
return users; V@o#" gZ
} wA\a ]X.
D6,Ol4d
/** %E2V$l0
* @param page d.$0X/0
* The page to set. }'`}| pM$
*/ 3/V0w|ZgD
publicvoid setPage(Page page){ #
11<=3Yj
this.page = page; QD^q\9U[
} (;9j#x
Y_nl9}&+C0
/** GB4^ 4Ajx
* @param users QjOY1Xze
* The users to set. MSE0z!t
*/ {t!Pv2y<
publicvoid setUsers(List users){ qs{wrem
this.users = users; %>!W+rO,
} J
p)I9k,Ez
X`28?
/** Yk0/f|>O
* @param userService `Wd4d2aLG
* The userService to set. '*D>/hn|:]
*/ |j=Pj)5J
publicvoid setUserService(UserService userService){ y({lE3P
this.userService = userService; <:4b4Nl
} SZvp%hS0
} qSt\ 6~
@%jY
c 5 `74g
fd$nAE
*alifdp
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, {Z1KU8tp
rvuasr~
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 =q}Z2 OoYh
RFPcH8-u7
么只需要: Vsr"W@k_
java代码:
&H[7UyC
XT?wCb41R
Clb7=@f
<?xml version="1.0"?> Y`."=8R~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork P9W?sPnC5
&"(zK"O
1.0//EN" "http://www.opensymphony.com/xwork/xwork- YC(X=
D
wxJoWbn
1.0.dtd"> kB.CeG]tk
2!R+5^Iy
<xwork> + w'q5/`
8jY<S+[o
<package name="user" extends="webwork- "U/yq
!j%uwje\
interceptors"> ~G1B}c]
~OWpk)Vq
<!-- The default interceptor stack name q07H{{h/B
i*r ag0Mw
--> b=5ZfhIg[
<default-interceptor-ref -]t>'Q?
9/_~YY=/h
name="myDefaultWebStack"/> &?}A/(#
~C>clkZ
<action name="listUser" !%[fi[p
M%WO
class="com.adt.action.user.ListUser"> j2%fAs<
<param U>sEFzBup
](FFvqA
name="page.everyPage">10</param> @,9YF}
<result 7'#_uAQR
s
bd$.6
|&
name="success">/user/user_list.jsp</result> djqw5kO:R
</action> "L!U7|9J
H%>^_:h
</package> Lrmhr3
w5
AiB]A}
</xwork> *Nfotv
[N#4H3GM8
Km,%p@`m
$+PyW(
r
6Yc(|>b!
'j-U=2,n
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Wt=\hixj-
|AT`(71
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 )x~/qHt
v!$:t<-5N
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 j^WYMr,
j+rY
L6#4A3yh
=k>fW7e
m41%?uC/
我写的一个用于分页的类,用了泛型了,hoho 9s*QHCB0
Q7-iy
java代码: c3 )jsf
iXq*EZb"R
F`GXho[
package com.intokr.util; +z:>Nl
/4N ?v. jf
import java.util.List;
*;xGH
3@:O1i
/** W 1u!&:O
* 用于分页的类<br> v*&jA8D
* 可以用于传递查询的结果也可以用于传送查询的参数<br> u:Ye`]~o
* BMqr YW
* @version 0.01 7t1as.
* @author cheng Ql%B=vgKL
*/ UNK.39
public class Paginator<E> { g5RH:]DV
privateint count = 0; // 总记录数 p<z eaf0W
privateint p = 1; // 页编号 5S,Kq35$(
privateint num = 20; // 每页的记录数 8&nb@l
privateList<E> results = null; // 结果 I9Uj3cL\
G&@dJ &B
/** R7K`9 c1f6
* 结果总数 Xk/iyp/
*/ ~y?Nn8+&f
publicint getCount(){ z>\l%_w
return count; |>[qC O
} &]GR*a
*X{7m]5
publicvoid setCount(int count){ X6T[+]Gc
this.count = count; ^b|I^TN0
} =<7z
:]
`6lOq H
/** hlZ{bO'f
* 本结果所在的页码,从1开始 IC (:RtJ
* :U *8S\$
* @return Returns the pageNo. 5Zd oem
*/ FJ4,|x3v[x
publicint getP(){ .6LRg
return p; znSlSQpTv
} I$p1^8~L
: p)R,('g
/** ij!],
* if(p<=0) p=1 TLp2a<Iy
* Z4c'1-lh
* @param p /qMnIo
*/ TOF V`7q;3
publicvoid setP(int p){ RwYFBc
if(p <= 0) 4/k`gT4
p = 1; Aj=GekX{
this.p = p; !h|,wq]k
} S,ea[$_
9#m3<oSJ
/** #/jug[wf*!
* 每页记录数量 W$2\GPJt
*/
iF":c}$.
publicint getNum(){ /H"fycZ
return num; _)~1'tCs}h
} qp/1tC`
I>JE\## ^n
/** k52IvB@2
* if(num<1) num=1 MmfBFt*
*/ &M@c50&%
publicvoid setNum(int num){ (_8.gS[
if(num < 1) Jwfb%Xge~
num = 1; /d,u"_=l
this.num = num; ~*"ZF-c,
} 9(OeH7
d(TN(6g@
/** J*MH`;-
* 获得总页数 a/J Mg
*/ c61OT@dZEA
publicint getPageNum(){ !02y'JS1
return(count - 1) / num + 1; hc[J,yG
} xr]bH.>
Ez"*',(
/** Y]KHCY
* 获得本页的开始编号,为 (p-1)*num+1 dNNXMQ0"
*/ D)?%kNeA
publicint getStart(){ jf`w8*R
return(p - 1) * num + 1; tgl(*[T2
} (H&HSs
4x(m.u@
/** t-o,iaPG3
* @return Returns the results. }$ySZa9
*/ .r{t&HO;Y
publicList<E> getResults(){ m_CWVw
return results; U5TkgHN{y
} tpEy-"D&
0%%U7GFB5
public void setResults(List<E> results){ IN<nZ?D#
this.results = results; OylUuYy~j
} yj#FO'UY
ZJU
%&@
public String toString(){ iQ(j_i'+!I
StringBuilder buff = new StringBuilder _pZ
<
Z37Dv;&ZD
(); JVkuSIR>
buff.append("{"); j5" L
buff.append("count:").append(count); dsx<ZwZN>
buff.append(",p:").append(p); &9)/"
buff.append(",nump:").append(num); 8s2y!pn7Q
buff.append(",results:").append f=}T^Z<
ymqv@Byi8A
(results); u"(NN9s
buff.append("}"); }4!}vkVx
return buff.toString(); LKp;sV
} 0)g]pG8&ro
.\T!oSb4[
} W_E^+Wl@
)Z1&`rv
d^nO&it