Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1UMEbb
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O C&BJNOi
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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 L(3&,!@
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 -
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分页支持类: vv)q&,<c
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java代码: Xm,fyk>
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package com.javaeye.common.util; Z`kVyuQ
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import java.util.List; \:@6(e Bh
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publicclass PaginationSupport { ,=e.QAF!"
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publicfinalstaticint PAGESIZE = 30; f}yRTR GJv
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privateint pageSize = PAGESIZE; k;cIEEdZD
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privateList items; Ko&4{}/
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privateint totalCount; 2=?3MXcjy
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privateint[] indexes = newint[0]; %e[E@H 7
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privateint startIndex = 0; Wu6'm&t
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public PaginationSupport(List items, int &yP|t":HWX
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totalCount){ v2tVq_\AMx
setPageSize(PAGESIZE); I:t?# )wl
setTotalCount(totalCount); 1>[#./@
setItems(items); jW7ffb
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setStartIndex(0); &IXmy-w
} g}R#0gkdk}
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public PaginationSupport(List items, int `}`Q qv
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totalCount, int startIndex){ T}{zh
setPageSize(PAGESIZE); rI\5djiYJ
setTotalCount(totalCount); -'O|D}
setItems(items); G(?1 Urxi
setStartIndex(startIndex); khjdTq\\
} Lios1|5
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public PaginationSupport(List items, int 8+Tv@
-J=6)
totalCount, int pageSize, int startIndex){ 6Br^Ugy
setPageSize(pageSize); :@5{*o
setTotalCount(totalCount); 2u-J+
setItems(items); 2!LDrvPP
setStartIndex(startIndex); CH(Y.Kj-
} ]35`N<Ac
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publicList getItems(){ ]@21K O
return items; q.R(>ZcV
} =c 9nC;C
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publicvoid setItems(List items){ s]e`q4ip
this.items = items; .Y2Hd$rs
} =\u,4
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publicint getPageSize(){ mW {uChHP
return pageSize; uX!6:v]
} prt(xr4@
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publicvoid setPageSize(int pageSize){ _\yR/W~
this.pageSize = pageSize; CB-;Jqb
} _'Jjt9@S
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publicint getTotalCount(){ s>G]U)d<'
return totalCount; !wUznyYwt
} |5`ecjb.
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publicvoid setTotalCount(int totalCount){ {S+?n[1r\
if(totalCount > 0){ (!8b$)k
this.totalCount = totalCount; z&n2JpLY7
int count = totalCount / iku*\,6W
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pageSize; %^E7Iqc
if(totalCount % pageSize > 0) 4 a&8G
count++; y5=,q]Qjk[
indexes = newint[count]; ZJcX-Z!\
for(int i = 0; i < count; i++){ #J3}H
indexes = pageSize * #?r|6<4X
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i; E<tR8='F
} 2!}F+^8'P
}else{ {5
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this.totalCount = 0; LKI\(%ba#
} )M"NMUuU"
} 3QZm
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publicint[] getIndexes(){ 6&'kN2
return indexes; li?@BHEf
} P 0+@,kM
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publicvoid setIndexes(int[] indexes){ H;_Ce'oU(
this.indexes = indexes; />8A?+g9u
} |uz<)
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publicint getStartIndex(){ u/|@iWK:
return startIndex; ><IWF#kUA
}
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publicvoid setStartIndex(int startIndex){ M0C)SU5"
if(totalCount <= 0) FsO-xG"@"
this.startIndex = 0; KC; o
elseif(startIndex >= totalCount) S]%,g%6i
this.startIndex = indexes W{q
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[indexes.length - 1]; Md>C!c
elseif(startIndex < 0) CDtL.a\
this.startIndex = 0; F~E)w5?\O
else{ [~|k;\2 +
this.startIndex = indexes PX^k;
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[startIndex / pageSize]; XW8@c2jN\7
} `{K-eHlrM9
} 0e#PN@
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publicint getNextIndex(){ bG"FN/vg
int nextIndex = getStartIndex() + OSUiS`k
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pageSize; >{~xO 6H
if(nextIndex >= totalCount) 8r[TM
return getStartIndex(); ^Lfwoy7R
else D2D+S
return nextIndex; "WGKwi=W
} Z>3~n
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publicint getPreviousIndex(){ X#0yOSR
int previousIndex = getStartIndex() - WwnBe"7M
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pageSize; .Xf_U.h$*@
if(previousIndex < 0) ,-EN{ed
return0; tGl|/
else 0)h.[O8@>
return previousIndex; NW0se
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} 4%qmwt*p
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} DH_~,tK9
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抽象业务类 />9`Mbg[G
java代码: V#b*:E.cA
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/** $?:IRgAr
* Created on 2005-7-12 d72
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*/ :&z!o"K
package com.javaeye.common.business; t W
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import java.io.Serializable; 3kGg;z6
import java.util.List; g9g ]X
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import org.hibernate.Criteria; qx >Z@o
import org.hibernate.HibernateException; Fv/{)H<:y
import org.hibernate.Session; r?0w5I
import org.hibernate.criterion.DetachedCriteria; :Zq?V`+M
import org.hibernate.criterion.Projections; FChW`b&S
import PeEaF@#k
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org.springframework.orm.hibernate3.HibernateCallback; p'@z}T?F
import 3~WI3ZIR
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org.springframework.orm.hibernate3.support.HibernateDaoS si]MQ\i+
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upport; [!KsAsmk
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import com.javaeye.common.util.PaginationSupport; 'S
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public abstract class AbstractManager extends xQ?$H?5B<
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HibernateDaoSupport { 7I(QTc)*
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privateboolean cacheQueries = false; 9*n?V ;E
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privateString queryCacheRegion; I7f:T N
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publicvoid setCacheQueries(boolean wz:,gpH
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cacheQueries){ @v/Ae_q!
this.cacheQueries = cacheQueries; R>[G6LOG
} *a(GG
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publicvoid setQueryCacheRegion(String {t'SA]|g
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queryCacheRegion){ %|2x7@&s
this.queryCacheRegion = +rrA>~
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queryCacheRegion; R\6dvd
} d.U"lP/)D
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publicvoid save(finalObject entity){ x+Ly,9nc$
getHibernateTemplate().save(entity); N_0B[!B]
} >dDcm
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publicvoid persist(finalObject entity){ ub4(g~E
getHibernateTemplate().save(entity); 8*]dAft
} ~Bt>Y
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publicvoid update(finalObject entity){ 3XUie;*`
getHibernateTemplate().update(entity); }qhND-9#@
} _#<7s`i
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publicvoid delete(finalObject entity){ !,DA`Yt
getHibernateTemplate().delete(entity); |L
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} BDi+*8
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publicObject load(finalClass entity, $|19]3T@Z
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finalSerializable id){ hi ),PfAV
return getHibernateTemplate().load 8/|1FI
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(entity, id); $j0<ef!
} '^:q|h
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publicObject get(finalClass entity, xI5zP?
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finalSerializable id){ #4& <d.aw'
return getHibernateTemplate().get uX&Tn1Kg
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(entity, id); TzV~I\a|
} )5s-"o<
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publicList findAll(finalClass entity){ Qy'-3GB
return getHibernateTemplate().find("from 8H{9
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" + entity.getName()); SiT5QJe
} hJoh5DIE95
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publicList findByNamedQuery(finalString J/A UOInh
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namedQuery){ $"{I|UFC
return getHibernateTemplate "l-b(8n
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().findByNamedQuery(namedQuery); 9Ui|8e~=
} wB%;O `Oh
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publicList findByNamedQuery(finalString query, x1 1ug
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finalObject parameter){ 5[rA>g~
return getHibernateTemplate BGL-lJrG
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().findByNamedQuery(query, parameter); EceD\}
} gib;> nuBK
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publicList findByNamedQuery(finalString query, 1(m[L=H5>
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finalObject[] parameters){ #9@UzfZAwT
return getHibernateTemplate hXP'NS`iv
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().findByNamedQuery(query, parameters); 4k=LVu]Kcr
} "I&,':O+
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publicList find(finalString query){ 9{n?Jy
return getHibernateTemplate().find E9PD1ADR
:pg]0X;
(query); } !RBH(m%
} {{e+t8J??
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publicList find(finalString query, finalObject tLe"i>
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parameter){ APL #-`XC
return getHibernateTemplate().find `>skcvkm
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(query, parameter); 3v:c'R0
} g,""j`
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public PaginationSupport findPageByCriteria ];au!
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(final DetachedCriteria detachedCriteria){ ttA0*
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return findPageByCriteria fs%l j_t
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); RI-)Qx&!f
} " 2J2za
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public PaginationSupport findPageByCriteria " )/febBS
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(final DetachedCriteria detachedCriteria, finalint '"o&BmF
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startIndex){ cuo'V*nWQ
return findPageByCriteria ?D`h[ai
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(detachedCriteria, PaginationSupport.PAGESIZE, $jgEB+
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startIndex); n6s[q-td
} s2Hx?~
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public PaginationSupport findPageByCriteria 2C_/T8
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(final DetachedCriteria detachedCriteria, finalint w@"l0gm+u[
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pageSize, :~{x'`czJ
finalint startIndex){ /5 6sPl
7}
return(PaginationSupport) P
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getHibernateTemplate().execute(new HibernateCallback(){ P{_Xg,Z
publicObject doInHibernate 47
*,
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(Session session)throws HibernateException { >,s.!vpK
Criteria criteria = JVk"M=c
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detachedCriteria.getExecutableCriteria(session); n%1I}?$fO
int totalCount = S@PAtB5
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((Integer) criteria.setProjection(Projections.rowCount Zbobi,
5<?s86GHh'
()).uniqueResult()).intValue(); ?cdjQ@j~h
criteria.setProjection :^oF0,-qZ
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(null); %qj8*1
List items = H^N
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criteria.setFirstResult(startIndex).setMaxResults 6 (@U+`
}E%#g#
(pageSize).list(); .uGvmD<;x
PaginationSupport ps = mcB8xE
}uaRS9d
new PaginationSupport(items, totalCount, pageSize, cXY;Tw45
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startIndex); |0e7<[
return ps; +^\TG>le
} @CJ`T&
}, true); 4$^\s5 K
}
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public List findAllByCriteria(final D#I^;Xg0h
=T0;F0@#4
DetachedCriteria detachedCriteria){ Sb;=YW
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return(List) getHibernateTemplate WzwH;!
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().execute(new HibernateCallback(){ #uzp
publicObject doInHibernate 2[8C?7_K0?
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(Session session)throws HibernateException { ^[]@dk9
Criteria criteria = )* \N[zm
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detachedCriteria.getExecutableCriteria(session); !lk
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return criteria.list(); -lv(@7o~
} ;9 ChBA
}, true); q*a~9.i@
} c1y+kvv
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public int getCountByCriteria(final ,jw`9a
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DetachedCriteria detachedCriteria){ i-@V
Integer count = (Integer) j]R[;8g
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getHibernateTemplate().execute(new HibernateCallback(){ KPjAk
publicObject doInHibernate jk\V2x@DR
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(Session session)throws HibernateException { !V/7q'&t=
Criteria criteria = 4UzXTsjM7
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detachedCriteria.getExecutableCriteria(session); >*!^pbZfX
return oZl%0Uy?9I
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criteria.setProjection(Projections.rowCount 9zCuVUcd$.
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()).uniqueResult(); YH^@8
} |68/FJZ,5
}, true); e:.?T\
return count.intValue();
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} u5KAwMw%Q
} %Lh+W<;
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用户在web层构造查询条件detachedCriteria,和可选的 m@w469&<(q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ZBN,%P!P0
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PaginationSupport的实例ps。 DUF$-'A
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ps.getItems()得到已分页好的结果集 k"/Rjd(;
ps.getIndexes()得到分页索引的数组 Ip)u6We>I
ps.getTotalCount()得到总结果数 a1%}Ee
ps.getStartIndex()当前分页索引 AP1ZIc6
ps.getNextIndex()下一页索引 *W>, 98
ps.getPreviousIndex()上一页索引 Y3(I;~$!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 qK9A
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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 ^W@%(,xb
k hD)x0'b
一下代码重构了。 Hz==,NR-W
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我把原本我的做法也提供出来供大家讨论吧: [/VpvQ'
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首先,为了实现分页查询,我封装了一个Page类: i1m>|[@k
java代码: v&WK9F\
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/*Created on 2005-4-14*/ g;nLR<]
package org.flyware.util.page; o76!7
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/** &/)B d%
* @author Joa )|k#cT{=M
* la!U
*/ g`fMHU7
publicclass Page { 6akI5\b
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/** imply if the page has previous page */ 4>v O9q
privateboolean hasPrePage; *n7=m=%)
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/** imply if the page has next page */ +'MO$&6
privateboolean hasNextPage; 8TP~=qU
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/** the number of every page */ .s!0S-RkC
privateint everyPage; #)twk`!^
4\ *:Lc,-
/** the total page number */ (FaYagD
privateint totalPage; -1v9
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/** the number of current page */ m{X{h4t
privateint currentPage; >wt.)c?5
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/** the begin index of the records by the current f5b|,JJ
U1E@pDH
query */ dh [kx
privateint beginIndex; SOM? 0.
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/** The default constructor */ D6&P9e_5
public Page(){ ]Sa#g&}T>
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} L8f+uI
I
*sT*;U
/** construct the page by everyPage c$2kR:
* @param everyPage 3Wbd=^hRvq
* */ 'PY;
public Page(int everyPage){ M:%g)FgW
this.everyPage = everyPage; lnyq%T[^
} %7aJSuQN%
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/** The whole constructor */ oST)E5X;7
public Page(boolean hasPrePage, boolean hasNextPage, W,Q>3y*
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int everyPage, int totalPage, stUv!
int currentPage, int beginIndex){ :.XlAQR~b
this.hasPrePage = hasPrePage; { >izfG,\
this.hasNextPage = hasNextPage; d$bO.t5CLh
this.everyPage = everyPage; Dbj?l;'1
this.totalPage = totalPage; ||pOiR5
this.currentPage = currentPage; fg#e*7Odn
this.beginIndex = beginIndex; ArAe=m!u
} XIbxi
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/** ro<w8V9.a
* @return $poIWJM c
* Returns the beginIndex. T5ky:{Y(
*/ 2ns,q0I
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publicint getBeginIndex(){ @Q2E1Uu%
return beginIndex; 3I( n];
} m]MR\E5]By
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/** dO1m
* @param beginIndex
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* The beginIndex to set. ,"#nJC
*/ UMd.=HC L
publicvoid setBeginIndex(int beginIndex){ t!/~_}eD J
this.beginIndex = beginIndex; 'R+^+urq^
} y< dBF[
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/** %u&Vt"6m=
* @return X{Vs
* Returns the currentPage. (EWGX |QA
*/ 86-Rm
publicint getCurrentPage(){ R,PN?aj
return currentPage; uuFQTx))
} WK*tXc_[b
]3*w3Y!XK
/** oowofi(E
* @param currentPage F3!@|/<w
* The currentPage to set. )hO%W|
*/ *lLCH,
publicvoid setCurrentPage(int currentPage){ s,[I_IiPf
this.currentPage = currentPage; }#e=*8F7
} I$+=Fb'N0
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/** HiK+}?I
* @return <#M1I!R
* Returns the everyPage. 8h|} Q _
*/ ivl %%nY'
publicint getEveryPage(){ &glh >9:G
return everyPage; ~$4(|Fq/
} <$A/ ('
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/** %4x0^<k~
* @param everyPage !+@70|gFF
* The everyPage to set. [|*7"Q(
*/ ceks~[rP
publicvoid setEveryPage(int everyPage){ |*zgX]-+;
this.everyPage = everyPage; '*Dp2Y{7
} qlPIxd
]-#/wC[$l=
/** AG vhSd7
* @return r 56~s5A
* Returns the hasNextPage. ~e[qh+
*/ R|qNyNXo[
publicboolean getHasNextPage(){ 85|u;Fxf
return hasNextPage; /K!f3o+
} 5 8;OTDR!
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/** Pr%KcR ;
* @param hasNextPage FG71<}C[K
* The hasNextPage to set. FYC]^D
*/ =(TMcu$4`
publicvoid setHasNextPage(boolean hasNextPage){ n9&fH
this.hasNextPage = hasNextPage; X04LAYY_u
} J#@+1 Nt
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/** 4<1V
* @return s-SFu
* Returns the hasPrePage. e"sv_$*
*/ G){+.X4g3
publicboolean getHasPrePage(){ o%lxEd r
return hasPrePage; P>~Usuf4
} .@;5"
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/** #>~A-k)
* @param hasPrePage tNZZCdB
* The hasPrePage to set. L5d
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*/ [\Aws^fD_
publicvoid setHasPrePage(boolean hasPrePage){ ^P [#YO
this.hasPrePage = hasPrePage; &dw=jHt
} l&W:t9o
}NV<k
/** y[cc<wm$
* @return Returns the totalPage. OOnj(%g
* N@'l:N'f4
*/ T51oNO%^
publicint getTotalPage(){ z8D,[`
return totalPage; D"fjk1
} g?j^d:
P$ b5o
/** 'f %oL/,
* @param totalPage -s0J8b
* The totalPage to set. ,@N.v?p>
*/ :m'(8s8
publicvoid setTotalPage(int totalPage){ 3|3ad'
this.totalPage = totalPage; Q3t%JP>;g
} [%Dh0hOg
V0#E7u`4
} ">fRM=fl
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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 8|hi2Qeu,c
K_N`My
个PageUtil,负责对Page对象进行构造: [c=![*}/
java代码: fl_a@QdB#
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/*Created on 2005-4-14*/ 3] U/^f3
package org.flyware.util.page; 2v*X^2+
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import org.apache.commons.logging.Log; hNp.%XnnZ
import org.apache.commons.logging.LogFactory; f,@~@f
X
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/** ]HG>Og
* @author Joa 6H|T )
* c8cGIAOY)
*/ ; Oz
p
publicclass PageUtil { "KY]2v.
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privatestaticfinal Log logger = LogFactory.getLog n2(\pQKm
MB.LHIo
(PageUtil.class); `
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/** v[m1R'
* Use the origin page to create a new page m{6*ae
* @param page 57U;\L;ZmZ
* @param totalRecords F@X8a/;F-
* @return X=JAyxY
*/ ^DR`!.ttr
publicstatic Page createPage(Page page, int .noY[P8i
p*Hf<)}
totalRecords){ =Ajw(I[56
return createPage(page.getEveryPage(), xSjs+Y;Mu
w6k^|."
page.getCurrentPage(), totalRecords); d8f S79
} VDv>I 2%
& =vi]z:[
/** }e,*'mCC*
* the basic page utils not including exception EPeV1$
8DlRD$_:&
handler Uw>g^[V;
* @param everyPage wQ9fPOm
* @param currentPage mz .uK2l{
* @param totalRecords T(eNK
c2
* @return page cU=EXyP%
*/ EF'U`\gX
publicstatic Page createPage(int everyPage, int )G9,5[
q VJC O-K|
currentPage, int totalRecords){ :U#4H;kk~j
everyPage = getEveryPage(everyPage); p4wXsOQ}
currentPage = getCurrentPage(currentPage); +p)kemJ~
int beginIndex = getBeginIndex(everyPage, '\Hh
3sBu`R*hk
currentPage); KZTT2KsYl
int totalPage = getTotalPage(everyPage, nSV
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\RyW#[(
totalRecords); ~G`(=\_0
boolean hasNextPage = hasNextPage(currentPage, ]1n
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9.$k^|~
totalPage); k:kx=K5=4
boolean hasPrePage = hasPrePage(currentPage); Ja#ti y
ZZ{:f+=?$
returnnew Page(hasPrePage, hasNextPage, q:ZF6o`Z83
everyPage, totalPage, $[8GFv
currentPage, gS4@3BOw&.
V@Fj!/
beginIndex); ;3WVrYe
} *J] }bX
3)+}2
privatestaticint getEveryPage(int everyPage){ Qf}b3WEAI
return everyPage == 0 ? 10 : everyPage; :Sd
iG=t
} $17utJ58
Vi1=
E])
privatestaticint getCurrentPage(int currentPage){ $&iw (BIq
return currentPage == 0 ? 1 : currentPage; 7nAB^~)6l
} n[pW^&7x
StJ&YYdD
privatestaticint getBeginIndex(int everyPage, int vEIDf{
A~Ov(
currentPage){ 8 P=z"y
return(currentPage - 1) * everyPage; `-L{J0xq
} k&PxhDf
2-*zevPiG=
privatestaticint getTotalPage(int everyPage, int @NS=
Wp<4F6C$@
totalRecords){ .A`Q!
int totalPage = 0; BHh%3Q
h{&}p-X&[
if(totalRecords % everyPage == 0) 5&\%
totalPage = totalRecords / everyPage; b-rgiR$cg
else B2PjS1z2
totalPage = totalRecords / everyPage + 1 ; Ht Z3n"2
Z&!5'_9{V
return totalPage; >Hq)1o
} A[@xTqs{{
prx)Cfv
privatestaticboolean hasPrePage(int currentPage){ l|c#
return currentPage == 1 ? false : true; ,dM}B-
} t_PAXj
`|\z#Et
privatestaticboolean hasNextPage(int currentPage, Rh:edQ#
&cEQ6('H
int totalPage){ 1 U|IN=
return currentPage == totalPage || totalPage == kCO`JAH#
Jf-4Q!
0 ? false : true; $-zt,iRyV
} FCu0)\
-c"nx$
vnT'.cBB:^
} o+o'!)
`J%iFm/5*
b'Scoa7@'
)c:i'L
gn>qd6P
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。 Ps@a@d"83
a&3pPfC
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 mT@8(
?=X G#we
做法如下: G(2(-x"+
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 y6bl&_
6PF7Wl7.
的信息,和一个结果集List: {G:dhi
java代码: Sl,\<a
.""?k[f5Q
0=3Av8
/*Created on 2005-6-13*/ 1Y2]jz4
package com.adt.bo; MCBZq\c
T2Q`Ax7
import java.util.List; HAof,* h$
tnv @`xBn
import org.flyware.util.page.Page; sYQ=nL
AATiI+\S
/** 9A@/5Z:v5W
* @author Joa 'P1I-ue
*/ ^W&qTSjh
publicclass Result { +HGPn0As
$e
bx
private Page page; eI%{/>
D"x;/I
private List content; C5q
n(tv
\e89 >m
/** nH6Ny
* The default constructor /i'dhiG
*/ |\PI"rW
public Result(){ .c+NsI9}
super(); ~N<zv({lG
} xc4g`Xi
h!k[]bt5
/** rD"$,-h
* The constructor using fields ZCP
r`H
* rb"J{^
* @param page TuF;>{~}
* @param content g4Y1*`}2f
*/ p\A!"KC
public Result(Page page, List content){ q5@N//<DNN
this.page = page; k}MmgaT:5]
this.content = content; :5YL!D/&
} +v!%z(
uq.!{3)8
/** UDBMf2F]
* @return Returns the content. NNOemTh
*/ dF@m4U@L
publicList getContent(){ zla^j,
return content; V8Lp%*(3
} 3FD6.X>x
$N; Nvp2
/** DG%vEM,y
* @return Returns the page. bdS
*/ e7n[NVrX
public Page getPage(){ kH.e"e
return page; f ye=8
r
} xtWwz}^8]
JX.3b_O
/** *n"{] tj^>
* @param content &U.U<
* The content to set. 5$58z
*/ ]!um}8!}
public void setContent(List content){ x6qQ
Y<>
this.content = content; [}mx4i
} uK6'TJ
rpB0?h!$
/** m }J@w~#
* @param page R^hlfKnt
* The page to set. V6L0\
*/ ^MXW,xqb
publicvoid setPage(Page page){ V*Q!J{lj^#
this.page = page; q6]T;)U&
} uht>@ WSg|
} @mD$Z09~
}zO>y%eI
0xEr`]]U
xlP0?Y1Bl
z]49dCN
2. 编写业务逻辑接口,并实现它(UserManager, 2FE13{+f
)8Q;u8jm1
UserManagerImpl) L2Vj2o"x?
java代码: 2]UwIxzR
2+oS'nL
ja-,6*"k
/*Created on 2005-7-15*/ Q2)CbHSz
package com.adt.service; Fd1t/B,
"XB6k0.#
import net.sf.hibernate.HibernateException; H#+2l?D:"
%(X^GL
import org.flyware.util.page.Page; B>kVJK`X
N hY`_?)
import com.adt.bo.Result; G'<Ie@$6l
EJid@
/** Nf^6t1se
* @author Joa h`@z61UI
*/ U&'Xsz
publicinterface UserManager { z=j,-d%9
Jwtt&" c0.
public Result listUser(Page page)throws p6&6^v\
}nK=~Wcu\
HibernateException; ZWb\^N
Swxur+hfH
} f{w[H S,z
wlEmy.)H
,7n8_pU
L$3{L"/
nj<nW5[
java代码: Srom@c
cR6Rb[9 N
_x]q`[Dih
/*Created on 2005-7-15*/ w?JM;'<AYQ
package com.adt.service.impl; Blox~=cW
~(-df>
import java.util.List; }Ryrd!3bY
QD;:!$Du
import net.sf.hibernate.HibernateException; ZPlY]e
_X~xfmU
import org.flyware.util.page.Page; {O_`eS
import org.flyware.util.page.PageUtil; }PX8#C_P
lbj_if;
import com.adt.bo.Result; m+EtB6r
import com.adt.dao.UserDAO; jyFKO[s\X
import com.adt.exception.ObjectNotFoundException; r:Ok z
import com.adt.service.UserManager; qpX`ZY^
l:14uWu|
/** tKCX0UZ'
* @author Joa @0D
*/ om1D} irKT
publicclass UserManagerImpl implements UserManager { W0LJXp-v
S.*.nv
private UserDAO userDAO; %TDY &@i=
8S@"6TG`
/** Os[50j!4>
* @param userDAO The userDAO to set. /MbWS(RT
*/ rds0EZ4 W
publicvoid setUserDAO(UserDAO userDAO){ o>y@1%aU
this.userDAO = userDAO; p sAr>:\3
} !4}Wp.
DxzNg_E]
/* (non-Javadoc) }3S6TJ+
* @see com.adt.service.UserManager#listUser >$_@p(w
S<Uv/pn
(org.flyware.util.page.Page) t}2M8ue(&
*/ S*(ns<L
public Result listUser(Page page)throws QV_Ep8
|K'7BK_^J
HibernateException, ObjectNotFoundException { RO.bh#A$
int totalRecords = userDAO.getUserCount(); 43/!pW
if(totalRecords == 0) wbbr8WiU
throw new ObjectNotFoundException fK5iOj'Q
%P`|kPW1
("userNotExist"); Q_FL8w9D~8
page = PageUtil.createPage(page, totalRecords); .!Q?TSQ+{!
List users = userDAO.getUserByPage(page); H 2UR
returnnew Result(page, users); X m%aT
} b)+;@wa~
xi! R[xr1
} h 7*#;j
H
JjW
RRJN@|"
c7/fQc)h4d
I#GsEhi
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 IjrjLp[z$
(0QYX[(r~o
询,接下来编写UserDAO的代码: o,DI7sb
3. UserDAO 和 UserDAOImpl: x#TWZ;
java代码: d;LBV<Z?
82~ZPZG
#{Gojg`5O
/*Created on 2005-7-15*/ P:tl)ob
package com.adt.dao; ^*+-0b;[G
Czt>?8x`
import java.util.List; Mf.:y
*Q:EICDE7
import org.flyware.util.page.Page; t?cO>4*|
sp&)1?!M
import net.sf.hibernate.HibernateException; 2:D1<z6RQ
]{E{ IW8
/** ^g*2jH+
* @author Joa r d4\N2- 6
*/ , K[}Bz
publicinterface UserDAO extends BaseDAO { T0Zv.
4f{(Scg
publicList getUserByName(String name)throws pm~uWXqxr=
4.0JgX
HibernateException; aBx8wl*Vm
>XiTl;UU
publicint getUserCount()throws HibernateException; Y]!{
nW
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publicList getUserByPage(Page page)throws D_4UM#Tw
Q)b*;
@
HibernateException; Xv1mjHZCC
*Mr?}_,X*
} 1%,AU
0(~,U!g[=
7Yrp#u1!
sVJwe\!
yvz2eAXa
java代码: W2\Q-4D
}v?_.MtS
0/Wo":R:
/*Created on 2005-7-15*/ :6Oh ?y@
package com.adt.dao.impl; .|g67PH=
X#!oG)or
import java.util.List; #aV2+ `d
EO[UezuU
import org.flyware.util.page.Page; ]C
me)&hX
7JI&tlR4\c
import net.sf.hibernate.HibernateException; 7iJ=~po:o
import net.sf.hibernate.Query; 7>Oa, \
,wvzY7%
import com.adt.dao.UserDAO; )FfJ%oT}
yIdM2#`u
/** M~1 n#
* @author Joa 0G.y_<=
*/ d\{#*{_A
public class UserDAOImpl extends BaseDAOHibernateImpl i+z;tF`
"/-T{p;.
implements UserDAO { 8v)PDO~D}A
D>c-h)2|
/* (non-Javadoc) 4l~0LdYXKm
* @see com.adt.dao.UserDAO#getUserByName D|1pBn.b]'
*?#t (Y[
(java.lang.String) EFgs}BV_9
*/ L8FLHT+R-
publicList getUserByName(String name)throws /}Z0\,
/{~cUB,Um
HibernateException { G
39
String querySentence = "FROM user in class .7HnWKUV
n?QpVROo\
com.adt.po.User WHERE user.name=:name"; EQ j2:9f
Query query = getSession().createQuery esM<.
nFn@Z'T$N
(querySentence); kXq*Jq
query.setParameter("name", name); T&2aNkuG
return query.list(); F+`DfI]/m
} +C{ %pF
I<I?ks
/* (non-Javadoc) # Z*nc0C
* @see com.adt.dao.UserDAO#getUserCount() %`c?cB
*/ 9xvE?8;M#
publicint getUserCount()throws HibernateException { Xja l6e)[
int count = 0; =~&Fq$$
String querySentence = "SELECT count(*) FROM J!QzF)$4J
E6-alBi%
user in class com.adt.po.User"; od- 0wJN-m
Query query = getSession().createQuery ~lR"3z_Z}
G}tq'#]E{z
(querySentence); "-N)TIzLX
count = ((Integer)query.iterate().next `nO!_3
^ftZ{uA
()).intValue(); f.gkGwNk
return count; 89B1\ff
} 0VV 1!g
T
x_n$ &
/* (non-Javadoc) IkSzjXE{
* @see com.adt.dao.UserDAO#getUserByPage y?-wjJS>
,/\%-u?
1x
(org.flyware.util.page.Page) =;{vfjj
*/ n8zh;vuJ
publicList getUserByPage(Page page)throws u OEFb
{Ex0mw)T
HibernateException { $S$%avRX
String querySentence = "FROM user in class ?K7m:Dx
%Gn(b1X
com.adt.po.User"; r4O*0Q_
Query query = getSession().createQuery @ :i>q$aF
O'deQq[
(querySentence); KM|[:v
query.setFirstResult(page.getBeginIndex()) P%smX`v
.setMaxResults(page.getEveryPage()); 8zz-jkR
return query.list(); -t
%.I=|
} -5A@FGh
Z94D<X"
} p&bQ_ XOH
u~?]/-.TY
KhZ'Ic[vw
Dw{C_e
'<m[
至此,一个完整的分页程序完成。前台的只需要调用 3}$L4U
A0S6 4(
userManager.listUser(page)即可得到一个Page对象和结果集对象 A]BD2
<acAc2
的综合体,而传入的参数page对象则可以由前台传入,如果用 BZsw(l4/0'
b/]C,P
webwork,甚至可以直接在配置文件中指定。 +98~OInySZ
}(J6zo9(x
下面给出一个webwork调用示例: 9 VkuYm,3
java代码: ~9]tt\jN*Y
$|z8WCJ
1kl4X3q6
/*Created on 2005-6-17*/ 9ZG.%+l
package com.adt.action.user; P 2;j>=W
kvSSz%R~
import java.util.List; fYx$3a.
LtH;#Q
import org.apache.commons.logging.Log; 50rq}-
import org.apache.commons.logging.LogFactory;
61T"K
import org.flyware.util.page.Page; s<z{ (a
rtf>\j+
import com.adt.bo.Result; V}7I?
G
import com.adt.service.UserService; tTF/$`Q#*
import com.opensymphony.xwork.Action; L ! yl^c
^b;.zhp8;N
/** O|%><I?I
* @author Joa sqac>v
*/ |;{wy
publicclass ListUser implementsAction{ 7Y@&&
Uh?SDay
privatestaticfinal Log logger = LogFactory.getLog $}W=O:L+D
vYmRW-1Zxq
(ListUser.class); J9I!d.U
u Dm=W36
private UserService userService; $C(}
Jh M.P9
private Page page; N\HOo-X
<G\q/!@_
privateList users; yWFDGk
`IkWS7|
/* [P)HVFy|l
* (non-Javadoc) Po(9BRd7
* z930Wi{@
* @see com.opensymphony.xwork.Action#execute() E7oL{gU
*/ >=6tfLQ
publicString execute()throwsException{ #s)6u?N
Result result = userService.listUser(page); )@\= pE.H
page = result.getPage(); k1_f7_m
users = result.getContent(); I
r<5%
return SUCCESS; :=T+sT~
} : )cPc7$8
{ >bw:^F
/** L@t<%fy@
* @return Returns the page. (.m0hN!~u
*/ b,]h X
public Page getPage(){ ;
R&wr_%
return page; oOmPbAY
} NK$k9,
M@E*_U!U
/** &^{HD }/{b
* @return Returns the users. loLQ@?E
*/ /al(=zf
publicList getUsers(){ GTeFDm;T^
return users; -s,^_p{H
} JC_Y#kN@z
uv/I`[@HK8
/** U_wn/wcLS
* @param page m@u!frE,
* The page to set. cX>
a>U
*/ py]m^)yc
publicvoid setPage(Page page){ Gvb>M=9
this.page = page; SirjWYap
} "<Dn%r
h*Rh:yCR>
/** .a8N 5{`
* @param users zy"L%i
* The users to set. X2}\i5{
*/ 68[3
/
publicvoid setUsers(List users){ SsIy ;l
this.users = users; +\fr3@Yc
} >8"oO[U5>
+?w 7Nm`
/** 1`^l8V(
* @param userService eB%KXPhMm
* The userService to set. r/$+'~apTk
*/ j&6,%s-M`a
publicvoid setUserService(UserService userService){ @{iws@.
this.userService = userService; :2pd2 S
} 9z$]hl
} AON";&dLq-
x%pC.0%
l"5$6h
6}='/d-[
:9Zu&t
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, F[<EXLQ
9f+|m9~2
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 0 #pjfc `:
([R}s/)$
么只需要: 1P#bR`I
>
java代码: }S<2({GI
es]\xw
l TY%,s
<?xml version="1.0"?> KE1S5Mck>
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork "u~l+aW0
xphw0Es
1.0//EN" "http://www.opensymphony.com/xwork/xwork- #~3x^4Y
a/;u:"
1.0.dtd"> '(mJ*Eb
JZQkr
<xwork> SlB,?R2
]wh8m1
<package name="user" extends="webwork- a\S"d
/e1m1 B
interceptors"> S+3'C
kq6S`~J^R
<!-- The default interceptor stack name X|K"p(N
W{O:j
--> zWoPa,
<default-interceptor-ref nr*~R-,\
P*oKcq1R
name="myDefaultWebStack"/> ("0@_05OH
sP$bp Z}
<action name="listUser" ["- pylhK
[SgWUP*
class="com.adt.action.user.ListUser"> `,i'vb`W#b
<param 4o8uWS{`
3t22KY[`
name="page.everyPage">10</param> |Ak>kQJ(1z
<result )W95)]
}^Be^a<ub
name="success">/user/user_list.jsp</result> >8Wvz.Nq/
</action> b/Y9fQn
J;h4)w~9H3
</package> Zs<}{`-
lS]<~
</xwork> @GqPU,RO
Z.Lm[$/edn
?Y+xuY/t
T0s7aw[zm
JIvVbI
YW"}hU
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 D.Rk{0se8
.Gq.s t%
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。 r`XIn#o
: Q X~bq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 <$wh@$PK
J01w\#62pQ
fx %Y(W#5
Vd3'dq8/?
F+PIZ%
我写的一个用于分页的类,用了泛型了,hoho Dww]D|M
*@o@>
java代码: !R;P"%PHV
vpXC5|9U
jcHs!
package com.intokr.util; H`q" _p:
+jYO?uaT
import java.util.List; E@TX>M-&
(A O]f fBU
/** sv\'XarM
* 用于分页的类<br> 'ah|cMRn
* 可以用于传递查询的结果也可以用于传送查询的参数<br> kv&%$cA
* ?g|K"P<1
* @version 0.01 '<~rV
* @author cheng D}'g4Ag
*/ "6_#APoP
public class Paginator<E> { .z&V!2zp
privateint count = 0; // 总记录数 6}
"?eW
privateint p = 1; // 页编号 4r#O._Z
privateint num = 20; // 每页的记录数 D
7 l&L
privateList<E> results = null; // 结果 +*'
pq_DYG]
/** 4NN-'Z>a
* 结果总数 9+@"DuYc6
*/ +#8?y
5~q
publicint getCount(){ k1Zu&4C\
return count; o^dt#
&
} b9ysxuUdS
u /!U/|
publicvoid setCount(int count){ fZ$<'(t
this.count = count; #n%?}
} cw.Uy(ks|$
AE!WYE
/** HVz-i{M
* 本结果所在的页码,从1开始 ~-x8@ /
* Fn$/ K
* @return Returns the pageNo. ^(m`5]qr7J
*/ f^](D'L?D
publicint getP(){ g0I<Fan
return p; 8yz A
W&q
} 2n+j.
zYpIG8"o5
/** +4\JY"oi
* if(p<=0) p=1 ,{ CgOz+Ul
* 'KpCPOhfR
* @param p fOiLb.BW
*/ /-z_"G
publicvoid setP(int p){ ]Vhhx`0
if(p <= 0) wOE_2k
p = 1; y$s}-O]/-
this.p = p; j>gO]*BX~
} ,]Yjo>`tW
X
+;Q=
/** s=#IoNh
* 每页记录数量 [?Y u3E\
*/ _tL+39 u
publicint getNum(){ . hHt+
return num; `}k!SqG
} a$#,'UB
FMY
r6/I
/** .Y'kDuUu
* if(num<1) num=1 !Y=s_)X
*/ Cih}
publicvoid setNum(int num){ Oz^+;P1
if(num < 1) ]@l~z0^|[_
num = 1;
&k\7fvF
this.num = num; 6_;3
} ERL(>)
M7yJ2u <Ty
/** Wr`=P,
* 获得总页数 #:T5_9p
*/ =N<Hc:<t4
publicint getPageNum(){ OW)8Z60
return(count - 1) / num + 1; ,qiS;2(
} R- `{W:S
.)|jBC8|}
/** kSU*d/}*u
* 获得本页的开始编号,为 (p-1)*num+1 \_@u"+,$W
*/ dge58A)Q
publicint getStart(){ wX#\\Jgi
return(p - 1) * num + 1; 1}S_CR4XBs
} v{H23Cfh:
)~d2`1zGS
/** BOL_kp"
* @return Returns the results. Z>QSZ48=
*/ wgLS9.
publicList<E> getResults(){ :KX/`
return results; z &<Rx[
} VmBLNM?
}C"#b\A2
public void setResults(List<E> results){ >ID 3oi
this.results = results; 2: pq|eiF
} ih+kh7J-
'U1r}.+b>
public String toString(){ [n74&EH
StringBuilder buff = new StringBuilder U45/%?kE)
lS?f?n^
(); aE,x>I 7 D
buff.append("{"); 5R"b1
buff.append("count:").append(count); Q7=J[,V: 2
buff.append(",p:").append(p); ~d{E>J77j
buff.append(",nump:").append(num); r{%NMj
buff.append(",results:").append Y%=A>~s*c:
gmLw. |-
(results); 9s*Lzi[}
buff.append("}"); Jr''S}@|x
return buff.toString(); @
K@~4!
} (O`=$e
Z@I%ppd
} jC\R8_
3\(s=-vh
`J-"S<c?_