Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 \;smH;m
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 U$(AZ|0
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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 \hwz;V.J"
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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 [8QE}TFic
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分页支持类: MzsDDP+h
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java代码: Ll L8Q
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package com.javaeye.common.util; D 4\T`j:
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import java.util.List; G6b\4}E
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publicclass PaginationSupport { !mX 2
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publicfinalstaticint PAGESIZE = 30; pPdOwK#
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privateint pageSize = PAGESIZE; LAwl9YnG:
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privateList items; L@{5:#-
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privateint totalCount; $iA`_H`W
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privateint[] indexes = newint[0]; 3Yd)Fm
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privateint startIndex = 0; ?N|B, F
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public PaginationSupport(List items, int Uv06f+P(
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totalCount){ >#RXYDd
setPageSize(PAGESIZE); [yF4_UoF
setTotalCount(totalCount); ega< {t
setItems(items); Tl!}9/Q5E:
setStartIndex(0); sGCV um}
} WBA0!
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public PaginationSupport(List items, int dB`YvKr#
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totalCount, int startIndex){ ;,y9
setPageSize(PAGESIZE); 46dh@&U
setTotalCount(totalCount); EnrRnVB
setItems(items); RJ%~=D
setStartIndex(startIndex); 5UwaBPj4
} By8C-jD
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public PaginationSupport(List items, int (,E.1j]ji
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totalCount, int pageSize, int startIndex){ .jhuC#x{/
setPageSize(pageSize); #GYCU!
setTotalCount(totalCount); r)dT,X[}F
setItems(items); $zTjh~ 9
setStartIndex(startIndex); dOFxzk,g&R
} H5Rn.n( |
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publicList getItems(){ tF)aNtX4^
return items; ~mtL\!vaM
} xcz1(R
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publicvoid setItems(List items){ 1@H3!V4
this.items = items; MdWT[
} 0j1I
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publicint getPageSize(){ qPpC )6-Q
return pageSize; 5vL]Y)l
} AR?J[e
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publicvoid setPageSize(int pageSize){ "~4ULl<i'
this.pageSize = pageSize; w $7*za2
} `n7z+
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publicint getTotalCount(){
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return totalCount; 6P'
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} <3QE3;4
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publicvoid setTotalCount(int totalCount){ }0T1* .Cz
if(totalCount > 0){ i+&*W{Re
this.totalCount = totalCount; =@m|g )
int count = totalCount / .h^."+TJ
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pageSize; Od'!v &
if(totalCount % pageSize > 0) ?0+D1w
count++; 9[|Ql
indexes = newint[count]; Pe/cwKCI
for(int i = 0; i < count; i++){ ]7ROCJ;
indexes = pageSize * #5T+P8
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} DL2gui3
}else{ A1p;Ye>o~
this.totalCount = 0; P}H7WH
} NrTQ}_3)
} "7RQrz
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publicint[] getIndexes(){ e.i5j^5u
return indexes; K.] *:fd
} O~B
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publicvoid setIndexes(int[] indexes){ `7Ni bZX0
this.indexes = indexes; '1=t{Rw
} 7
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publicint getStartIndex(){ ]]+wDhxH
return startIndex; 9S.Uo[YY
} pSASMc@
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publicvoid setStartIndex(int startIndex){ }7vX4{Yn
if(totalCount <= 0) @q2Yka
this.startIndex = 0; `Y/DttjL
elseif(startIndex >= totalCount) )oa6;=go
this.startIndex = indexes &&|*GAjJ
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[indexes.length - 1]; 0W9,uC2:N
elseif(startIndex < 0) G6Z2[Ej1
this.startIndex = 0; 4_`+&
else{ .-[UHO05^8
this.startIndex = indexes 'rU
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[startIndex / pageSize]; GLt#]I"LY
} ooByGQ90V:
} X#-U
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publicint getNextIndex(){ %?_pSH}$!
int nextIndex = getStartIndex() + ld4QhZia
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pageSize; R\MM2_I
if(nextIndex >= totalCount) _;{n+i[
return getStartIndex(); "a;JQ:
else k#E D#']N
return nextIndex; Q! ]
} 8\`]T%h
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publicint getPreviousIndex(){ veAGUE
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int previousIndex = getStartIndex() - 5Y"lr Y38
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pageSize; oKiBnj5J
if(previousIndex < 0) (J][(=s;a
return0; wnP#.[,V
else zhU)bb[A
return previousIndex; c{6!}0Q4
} MMD4b}p
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} Ej
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抽象业务类 a{QHv0goG
java代码: 1-1x,U7w
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/** ]k_@F6 A
* Created on 2005-7-12 D&/(Avx.
*/ ^~0\d;l_
package com.javaeye.common.business; Zk)]=<H
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import java.io.Serializable; I7nt<l!
import java.util.List; $&='&q
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import org.hibernate.Criteria; B[!wo
import org.hibernate.HibernateException; ATv.3cy
import org.hibernate.Session; L=Fm:O'#2
import org.hibernate.criterion.DetachedCriteria; # h]m8
import org.hibernate.criterion.Projections; ea=@r
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import ,g#=pdX;
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org.springframework.orm.hibernate3.HibernateCallback; jnYFA[Ab
import ^vLHs=<
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org.springframework.orm.hibernate3.support.HibernateDaoS .KGW#Qk8
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upport; 0"kNn5
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import com.javaeye.common.util.PaginationSupport; !,+peMy
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public abstract class AbstractManager extends @O5-w
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HibernateDaoSupport { .ZFs+8qU>
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privateboolean cacheQueries = false; E#`=xg
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privateString queryCacheRegion; \Q|1I
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publicvoid setCacheQueries(boolean
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cacheQueries){ G \?fWqx
this.cacheQueries = cacheQueries; ((\s4-
} 81fpeoNO
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publicvoid setQueryCacheRegion(String QDRSQ[ \
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queryCacheRegion){ Ka&[
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this.queryCacheRegion = q%w\UAqA
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queryCacheRegion; nKp='>Th
} Vz!W(+
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publicvoid save(finalObject entity){ ce\]o^4
getHibernateTemplate().save(entity); p3`'i
} P}KN*Hn.
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publicvoid persist(finalObject entity){ 57Q^"sl
getHibernateTemplate().save(entity); TggM/@k
} IExo#\0'6
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publicvoid update(finalObject entity){ +u#;k!B/>
getHibernateTemplate().update(entity); ykH?;Xu
} Eg-3GkC
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publicvoid delete(finalObject entity){ sWP5=t(i+9
getHibernateTemplate().delete(entity); Yj|Oy
} ,`v)nwP
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publicObject load(finalClass entity, K4YpE}]u
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finalSerializable id){ Dj'aWyW'
return getHibernateTemplate().load \?{nP6=
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(entity, id);
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} TYGUB%A
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publicObject get(finalClass entity, qv y~b
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finalSerializable id){ "jH=O(37
return getHibernateTemplate().get OW-[#r
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(entity, id); abh='5H|^|
} .p NWd
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publicList findAll(finalClass entity){ $73 7oV<
return getHibernateTemplate().find("from 0tv"tA;
ce{(5IC
" + entity.getName()); m_\w)
} >KmOTM<{
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publicList findByNamedQuery(finalString tT'*Uu5
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namedQuery){ ?2zVWZ
return getHibernateTemplate \ce (/I
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().findByNamedQuery(namedQuery); _]a8lr+_-
} q{5wx8_U
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publicList findByNamedQuery(finalString query, =T;>$&qs
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finalObject parameter){ 19Xc0ez
return getHibernateTemplate '^)Ve:K-.
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().findByNamedQuery(query, parameter); D7H,49#1Q
} @d]I3?`
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publicList findByNamedQuery(finalString query, / PDe<p
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finalObject[] parameters){ kwU~kcM
return getHibernateTemplate rxH*h`Xx@
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().findByNamedQuery(query, parameters); p%toD{$
} 7pMQ1-(
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publicList find(finalString query){ ^-?5=\`5
return getHibernateTemplate().find S=H<5*]g
++n"`
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(query); g+;)?N*j
} ,#3u.=IR[
/` 891(f,
publicList find(finalString query, finalObject 20750G
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parameter){ MG)wVS<d_
return getHibernateTemplate().find M>W-lp^3
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(query, parameter); J0CEZ
} @ FVan
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public PaginationSupport findPageByCriteria NSH20$A<
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(final DetachedCriteria detachedCriteria){ }`#OA]NZ
return findPageByCriteria dR~4*59Bg
qplz !=
(detachedCriteria, PaginationSupport.PAGESIZE, 0); P=PcO>
} 2g5Ft
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public PaginationSupport findPageByCriteria B7r={P!0
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(final DetachedCriteria detachedCriteria, finalint 5ws|4V
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startIndex){ l^aG"")TH.
return findPageByCriteria RzCC>-
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(detachedCriteria, PaginationSupport.PAGESIZE, I{Hl2?CnI,
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startIndex); e FDhJ
} zK`fX
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public PaginationSupport findPageByCriteria XOgl>1O
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(final DetachedCriteria detachedCriteria, finalint 7KIOI,qb6
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pageSize, -;pZC}Nd3
finalint startIndex){ a)J3=Z-
return(PaginationSupport) #v!(uuq,
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getHibernateTemplate().execute(new HibernateCallback(){ "{>I5<:t
publicObject doInHibernate %"tLs%"7=P
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(Session session)throws HibernateException { Lt ;!q b.
Criteria criteria = c4QegN
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detachedCriteria.getExecutableCriteria(session); 0"q_c-_Bg
int totalCount = %zj;~W;qPH
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((Integer) criteria.setProjection(Projections.rowCount HDqPqrWm
n5CjwLgu\b
()).uniqueResult()).intValue(); VK\ Bjru9
criteria.setProjection bB^% O^:
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(null); vzD3_
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List items = Q`mw2$zv
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criteria.setFirstResult(startIndex).setMaxResults `k y>M-
k^3 ?Z2a
(pageSize).list(); Z#7T!/28
PaginationSupport ps = *:t]|$;E\
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new PaginationSupport(items, totalCount, pageSize, ~5Wr
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startIndex); :&D>?{b0
return ps; |Y'xtOMX
} U 7mA~t2E
}, true); Eq$Q%'5*ua
} R^zTgyr
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public List findAllByCriteria(final 1(!w xJ
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DetachedCriteria detachedCriteria){ ?DPNa
return(List) getHibernateTemplate VsS.\1
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().execute(new HibernateCallback(){ i!
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publicObject doInHibernate vt{s"\f
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(Session session)throws HibernateException { V9xZH5T8^
Criteria criteria = *o]Q<S>lH
_nw=^zS
detachedCriteria.getExecutableCriteria(session); d>"t*>i]>
return criteria.list(); Z9-HQ5>
} mq~rD)T
}, true); GE4d=;5
} -$Bom
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public int getCountByCriteria(final zrfE'C8O
' k~'aZ
DetachedCriteria detachedCriteria){ \m @8$MK
Integer count = (Integer) b|U48j1A
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getHibernateTemplate().execute(new HibernateCallback(){ &sbA:xZBA
publicObject doInHibernate (lv|-Phc.
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(Session session)throws HibernateException { Jp)>Wd
Criteria criteria = n]&/?6}
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detachedCriteria.getExecutableCriteria(session); F@Bh>Vb
return MGn:Gj"d
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criteria.setProjection(Projections.rowCount h%e}4U@X
U" eP>HHp
()).uniqueResult(); (QQ /I;
} @l3L_;6a
}, true); 4>]^1J7Wz
return count.intValue(); 3md yY\+&
} 1B~H *=t4h
} b
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用户在web层构造查询条件detachedCriteria,和可选的 x7$U
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 v8!
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PaginationSupport的实例ps。 :b+C<Bp64r
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ps.getItems()得到已分页好的结果集 9k.LV/Y
ps.getIndexes()得到分页索引的数组 @+A`n21,O
ps.getTotalCount()得到总结果数 9:0JWW^so
ps.getStartIndex()当前分页索引 yO
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ps.getNextIndex()下一页索引 `X?l`H;#
ps.getPreviousIndex()上一页索引 %XGwQB$zk8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \ ?['pB
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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 kQlXcR
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一下代码重构了。 =]x FHw8A
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我把原本我的做法也提供出来供大家讨论吧: RW
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首先,为了实现分页查询,我封装了一个Page类: cad1eOT'
java代码: 8EZ"z
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/*Created on 2005-4-14*/ R{S{N2+p(
package org.flyware.util.page; M@@"-dy
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/** 2GECcx53
* @author Joa c0ET]
* *ie#9jA
*/ m;o \.s
publicclass Page { $oK,&_
.(Q3M0.D
/** imply if the page has previous page */ ^!H8"CdC3
privateboolean hasPrePage; pLMki=.Ld
'/
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/** imply if the page has next page */ NwM =
privateboolean hasNextPage; -WP_0
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/** the number of every page */ Q%~b(4E^7P
privateint everyPage; {>>ozB.
p"ht|x
/** the total page number */ ~]?Q'ER
privateint totalPage; &s_O6cqgh
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/** the number of current page */ k{Yj!C>
#
privateint currentPage; 4VLrl8$K
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/** the begin index of the records by the current S:{hgi,T*
[r_,BH\nu
query */ m *8[I
privateint beginIndex; O?NAbxkp
lwPK^)|}
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/** The default constructor */ l epR}
public Page(){ Y~RPspHW
n5"rSgUtE
} %*]3j^b Q+
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/** construct the page by everyPage 'wz*GMGWC
* @param everyPage _m0HgLS~
* */ rFZB6A<(]
public Page(int everyPage){ 5~4I.+~8
this.everyPage = everyPage; dsqqq,>Q
} j y{T=Nb
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/** The whole constructor */ 95^w" [}4Q
public Page(boolean hasPrePage, boolean hasNextPage, h";G vjy
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2S}%r4$n}
int everyPage, int totalPage, qQ%zSJ?
int currentPage, int beginIndex){ ZN5\lon|Y
this.hasPrePage = hasPrePage; laqKP+G
this.hasNextPage = hasNextPage; |{cdXbr
this.everyPage = everyPage; /ow/)\/}
this.totalPage = totalPage; 2qKo|'gL`
this.currentPage = currentPage; wIuwq>
this.beginIndex = beginIndex; ^sd+s ~xx
} z.oDH<1
?qYw9XQYL
/** #wbaRx@rc
* @return p#'BV'0bl
* Returns the beginIndex. Y&`Vs(
*/ $bh2zKB)
publicint getBeginIndex(){ 2fTkHBhn&
return beginIndex; %yJL-6U
} &$jg *Kr
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/** qO[6?q=c:
* @param beginIndex }Y[Z`w
* The beginIndex to set. A_T-]YQ
*/ zMt "ST.
publicvoid setBeginIndex(int beginIndex){ g"(
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this.beginIndex = beginIndex; J]nb;4w
} EnA) Rz
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/** Xj"/6|X
* @return fG;)wQJ
* Returns the currentPage. o %A4wEye
*/ L 7_Mg{
publicint getCurrentPage(){ U2/H,D
return currentPage; 75wQH*
} `rW{zQYM
:+ @-F>Q
/** h1G]w/.ws
* @param currentPage Y}'C'PR
* The currentPage to set. i;*c|ma1>
*/ 9c8zH{T_{
publicvoid setCurrentPage(int currentPage){ *fW&-ic
this.currentPage = currentPage; |M`B
} rAIX(2@cR_
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/** nVw]0Yl
* @return REB8_ H"
* Returns the everyPage. ?(>7v[=iT
*/ -r]s #$
publicint getEveryPage(){ D}vgXzD
return everyPage; 6Z
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} >FFZ8=
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/** vTQQd@
* @param everyPage ^2|gQ'7<
* The everyPage to set. uCF+Mp
*/ 7<x0LW
publicvoid setEveryPage(int everyPage){ F*>:~'%
this.everyPage = everyPage; uf\Hh -+p
} >},O_qx
t= "EbPE
/** ^v*ajy.>
* @return 6Bmv1n[X^h
* Returns the hasNextPage. f[.RAHjk
*/ pZ+zm6\$
publicboolean getHasNextPage(){ %>Z=#1h/a
return hasNextPage; 03J,NXs
} Ud^+a H
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/** 2W|4
* @param hasNextPage 71 hv~Nk/x
* The hasNextPage to set. $@Zb]gavt?
*/ s2_j@k?%
publicvoid setHasNextPage(boolean hasNextPage){ /#20`;~F)
this.hasNextPage = hasNextPage; 5|NM]8^^0[
} V%dMaX>^i
LPb43
/** FT/H~|Z>
* @return Dd<gYPC
* Returns the hasPrePage. idvEE6I@
*/ 8\!0yM#yK
publicboolean getHasPrePage(){ Q/\
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return hasPrePage; IpGq_TU
} fC.-* r
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/** Y<:%_]]
* @param hasPrePage ktU98Bk]
* The hasPrePage to set. Sq/M
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*/ ml.l( 6A
publicvoid setHasPrePage(boolean hasPrePage){ iBwl(,)?m2
this.hasPrePage = hasPrePage; l6Ze6X I
} kR7IZo"q
x%k4Lm
/** Ig"Krz
* @return Returns the totalPage. RR{]^g51
* 63UAN0K%
*/ @]6)j&
publicint getTotalPage(){ zOLt)2-<
return totalPage; <5@+:7Dv
} 50rCW)[#
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/** J
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* @param totalPage {Mp>+e@xx
* The totalPage to set. =+T{!+|6P
*/ Tcz67&c |W
publicvoid setTotalPage(int totalPage){ gdSv)(
this.totalPage = totalPage; 8*=N\'m],
} eqD%Qdx
bd_U%0)pi1
} :(} {uG
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u Y V=
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 w:r0>
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个PageUtil,负责对Page对象进行构造: S-gL]r3G8
java代码: ?#ndMv!$
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/*Created on 2005-4-14*/ #?}k0Y
package org.flyware.util.page; yf*MG&}
~ d/Doi
import org.apache.commons.logging.Log; v#IW;Rj8
import org.apache.commons.logging.LogFactory; %g5weiFM
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/** @,CCwiF'q
* @author Joa Z?oFee!4
* 4FQU$f
*/ Q5;Km1(
publicclass PageUtil { }KCXo/y
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privatestaticfinal Log logger = LogFactory.getLog _ p?lRU8
2fO ~%!.G
(PageUtil.class); BEg%u)"([
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/** 3xsC"c>
* Use the origin page to create a new page Rde#=>@V
* @param page IxYuJpi
* @param totalRecords 0+P_z(93?
* @return {K*l,U
*/ ,'= Y
publicstatic Page createPage(Page page, int sw' 20I
R/~j <.s3P
totalRecords){ I/|)?
return createPage(page.getEveryPage(), ~kS~v
r5(OH3
page.getCurrentPage(), totalRecords); p"Oi83w;9
} "@
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}pu2/44=W
/** 4Yt:PN2
* the basic page utils not including exception F04`MY"
j{7_p$JM
handler W6K]jIQ
* @param everyPage }bIEW ho
* @param currentPage @0A0\2
* @param totalRecords O1JGv8Nr
* @return page wS%I.
*/ ] \4-e2N`\
publicstatic Page createPage(int everyPage, int "#rlL^9v
S!#7]wtbP
currentPage, int totalRecords){ ?%JH4I2
everyPage = getEveryPage(everyPage); HGC>jeWd_
currentPage = getCurrentPage(currentPage); Um9!<G=;
int beginIndex = getBeginIndex(everyPage, 4_&$isq
U2ecvq[T
currentPage); r1}OlVbK
int totalPage = getTotalPage(everyPage, @=K> uyB
xRv1zHZ
totalRecords); O2:m)@
boolean hasNextPage = hasNextPage(currentPage, #8R\J[9
d}>Nl$
totalPage); jXGr{n
boolean hasPrePage = hasPrePage(currentPage); BpDf4)|
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returnnew Page(hasPrePage, hasNextPage, }qmZ
everyPage, totalPage, ?)",}XL6
currentPage, 7_E+y$i=
6^mO<nB
beginIndex); HMgZ&v
} !!o69
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privatestaticint getEveryPage(int everyPage){ .o:Pe2C
return everyPage == 0 ? 10 : everyPage; QP7EP aW
} s8WA@)L
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privatestaticint getCurrentPage(int currentPage){ QD+dP nZu
return currentPage == 0 ? 1 : currentPage; w<J$12
"p+
} 2(5wFc
`2J6Dz"W
privatestaticint getBeginIndex(int everyPage, int @-qxNw
t<|=-
currentPage){ fF_1ZKx+#!
return(currentPage - 1) * everyPage; kkyn>Wxv
} V*5:Vt7N
RT)0I;
privatestaticint getTotalPage(int everyPage, int ok-sm~ bp
n4>
totalRecords){ >`5iq.v
int totalPage = 0; n2Dnpe:
O(~`fN?n
if(totalRecords % everyPage == 0) Q'*-gg&)
totalPage = totalRecords / everyPage; }}cVPB7
else BtBy.bR
totalPage = totalRecords / everyPage + 1 ; f|Z3VS0x
OrPIvP<w@
return totalPage; u`gy1t `
} mXz-#Go(
$Fc*^8$ryC
privatestaticboolean hasPrePage(int currentPage){ 42Gr0+Mb
return currentPage == 1 ? false : true; qoB
} O*H:CW
MZ=U}
&F
privatestaticboolean hasNextPage(int currentPage, }UXj|SY
x@v,qF$K
int totalPage){ u 6la
return currentPage == totalPage || totalPage == -*e$>w[.N
&^63*x;hE
0 ? false : true; e~'y %| D
} 2i |wQU5w
]v rpr%K
3hO`GM
} @]H&(bw
a}M7"v9
bk2HAG
GQ2&D}zh
PLFM[t/
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。 j:)
(`
V,|l&-
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 m ~fqZK
y<BiR@%,7
做法如下: A{x&5yX8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]8+%57:E
/:ma}qGy
的信息,和一个结果集List: NZ{kjAd3c
java代码: L@CN0ezQs
jn]hqTy8
duXv
[1
/*Created on 2005-6-13*/ nP 2 rN_:4
package com.adt.bo; eff6=DP
^._)HM
import java.util.List; ~UK)
p;|
fR6ot#b
import org.flyware.util.page.Page; :Q+rEjw+
9VV
/** H$(%FWzQ%
* @author Joa "}7K>|a
*/ kVkV~
publicclass Result { @ewQx|
Y8m|f
private Page page; C([;JO
11[
*3S,XMS{O
private List content; (G#)[0<fX
y"e'Gg2
/** 1'c!9
* The default constructor {(D$Xb
*/ [Gh T.
public Result(){ MyCX6+Ci)
super(); @,M !&l
} P8DJv-f`
{*
>$aI
/** ^5=}Y>EJO
* The constructor using fields 0J@)?,V-.
* q$:T<mFK$
* @param page nHD4J;l
* @param content F3H)B:
*/ pA(@gisg
public Result(Page page, List content){ *Z|!%C
this.page = page; #OJ^[Zi<
this.content = content; S$BwOx3QF
} uPR usG4!R
b]4yFwb
/** {n$9o
* @return Returns the content. eW\7X%I
*/ ll[U-v{
publicList getContent(){ KDRIy@[e
return content; VH#]67
} rm2{PV<+d
OPwp(b
/** z}8rD}BH
* @return Returns the page.
G!XizhE
*/ t+m$lqm
public Page getPage(){ $Jb+}mlT
return page; W zy8
} NkNw9?:#4
@L{HT8utK3
/** ln9MVF'!&
* @param content (d4zNYK
* The content to set. ^tc@bsUF
*/ {r[*}Bv
public void setContent(List content){ WZ6!VE{
this.content = content; [g&Q_+,j
} 8*>6+"w
RUX!(Xw
/** ;op+~@*!
* @param page qO&:J\d
* The page to set. e3)rF5pp
*/ F~W*"i+EZ
publicvoid setPage(Page page){ ,dzbI{@6
this.page = page; 2#T|+mKxZM
} r'{pTgm#
} f+fF5Z\
?ohLcz
f[ %\LHq
1ww|km
&vdGKYs 6
2. 编写业务逻辑接口,并实现它(UserManager, p7zHP
d cPh@3
UserManagerImpl) @_1$
<8
java代码: V)!Oss;i
=J0FT2 d
DrHMlk5
/*Created on 2005-7-15*/ p_B,7@Jl
package com.adt.service; gOgG23 x
$'?CY)h{
import net.sf.hibernate.HibernateException; jpm}EOq<%
8{%/!ylJz
import org.flyware.util.page.Page; o)"}DeV$&
84)S0Y8w
import com.adt.bo.Result; j(/"}d3osm
OaU} 9&
/** t( p
* @author Joa dL6sb;7R
*/ *=^_K`y
publicinterface UserManager { I[tU}oj P
+vDT^|2SF
public Result listUser(Page page)throws }-:
d*YtK
() b0Sh=
HibernateException; =*8"ci$
!Q cgTW)T
} ~z32%k
3w!oJB
wpx,~`&
\&ERSk2
GlQ=M )E
java代码: (t<i?>p
/\
~{
V%Y.N4H
/*Created on 2005-7-15*/ Lm ,io\z
package com.adt.service.impl; f=}u;^
4J94iI>S.l
import java.util.List; jDH)S{k
I`Rxijz
import net.sf.hibernate.HibernateException; 97F$$d54T
iO<O2A.F
import org.flyware.util.page.Page; ^h^j:!76j
import org.flyware.util.page.PageUtil; eA{,=,v)
t
m5>J)C
import com.adt.bo.Result; 9L!Vj J
import com.adt.dao.UserDAO; zx#d_SVi
import com.adt.exception.ObjectNotFoundException; <XCH{Te1
import com.adt.service.UserManager; 47$JN}qI0
>s[}f6*2@
/** Z# 7HuAF{]
* @author Joa +1h^9Y'
*/ bTHJb pt*-
publicclass UserManagerImpl implements UserManager { 1;ZEuO
?em )om
private UserDAO userDAO; nez5z:7F
g.F{yX]
/** bgYM
* @param userDAO The userDAO to set. $Cc4Sggq
*/ ;h/Y9uYn
publicvoid setUserDAO(UserDAO userDAO){ "TN}=^A\F
this.userDAO = userDAO; 2R<1^
} 6D0uLh
2S!=2u+7
/* (non-Javadoc) e|+uLbN&;c
* @see com.adt.service.UserManager#listUser Sq(=Bn6E
~5p
`Kg*
(org.flyware.util.page.Page) 1(On.Y=
*/ @H7dQ,%
public Result listUser(Page page)throws
`I6)e{5t
2eyvY|:Q>
HibernateException, ObjectNotFoundException { jWP(7}U
int totalRecords = userDAO.getUserCount(); p)TH^87
if(totalRecords == 0) 'y'>0'et
throw new ObjectNotFoundException Eptsxyz{
Kq-y1h]7H
("userNotExist");
Ge(r6"%7
page = PageUtil.createPage(page, totalRecords); hrEKmRmF-
List users = userDAO.getUserByPage(page); v,g,c`BjK
returnnew Result(page, users); 3b%y+?-{\u
} CZwZ#WV6
I&1Mh4yu
} i}+dctg/
(_<ruwV]`
:Tj,;0#/
Hej0l^
VMen:
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +k8><_vr}
9;h1;9sC|
询,接下来编写UserDAO的代码: ^z0[{1
3. UserDAO 和 UserDAOImpl: [gQ~B1O
java代码: xvpS%MS
G
V0q?
&w/aQs~
/*Created on 2005-7-15*/ n6|}^O7
package com.adt.dao; r}*2~;:pW
$R7d*\(G
import java.util.List; u7a4taM$d
9%\q*
import org.flyware.util.page.Page; 9dKrE_zK:
BMFpkK9|
import net.sf.hibernate.HibernateException; I"<~!krt%
[Hn+r &
/** p(f)u]1`
* @author Joa @X1>Wv|[
*/ "b -KVZ
publicinterface UserDAO extends BaseDAO { WGp81DNS|
1*>a
publicList getUserByName(String name)throws S1`+r0Fk~n
hQ<"
HibernateException; w9.r`_-
mYa0_P%^
publicint getUserCount()throws HibernateException; ~^Vt)/}Q
HnOp*FP
publicList getUserByPage(Page page)throws kw=+"U
vQBfT% &Q-
HibernateException; W dIr3
p1X
lni%=
} Ev$?c9*>
\Sm.]=br
m0=CD
=>S5}6
+TUtVG
java代码: [@>Kd`!'
: 2?i9F0_
/6L\`\g
/*Created on 2005-7-15*/ 3n6_yK+D
package com.adt.dao.impl; /i^b;?/1
)5yZSdA
import java.util.List; EZBk;*=B
c#CX~
import org.flyware.util.page.Page; ;[dcbyu@
>@TZYdl
import net.sf.hibernate.HibernateException; V=E9*$b]
import net.sf.hibernate.Query; yt_?4Hc"
o{zo-:>Jp
import com.adt.dao.UserDAO; p|AIz3
! daXF&q
/** NG S/lKz
* @author Joa +-8uIqZ
*/ 5F
<zW-;
public class UserDAOImpl extends BaseDAOHibernateImpl ;t*45
>rYP}k
implements UserDAO { ]u2!)vZh'
h-jea1m
/* (non-Javadoc) <R]?8L0{h
* @see com.adt.dao.UserDAO#getUserByName B8B^@
(h`||48d
(java.lang.String) gX6'!}G8]
*/ $?;aW^E
publicList getUserByName(String name)throws OZk(VMuI
8$3 Tu"+;
HibernateException { ^pZ(^
String querySentence = "FROM user in class u-j Gv| ,|
Y
Xn)?
com.adt.po.User WHERE user.name=:name"; jOE b1
Query query = getSession().createQuery ? )0U!)tK
X}Fc0Oo
(querySentence); :ykQ[d`:|
query.setParameter("name", name); +s_@964
return query.list(); r 97 VX>
} O]lWaiR`
~} wPiu,
/* (non-Javadoc) P9Rq'u
* @see com.adt.dao.UserDAO#getUserCount() T7!a@
*/ hQl3F6-ud
publicint getUserCount()throws HibernateException { .c~;/@{
int count = 0; 5O*.qp?
String querySentence = "SELECT count(*) FROM BnAia3z
Eiz\Nb
user in class com.adt.po.User"; fqvA0"tv
Query query = getSession().createQuery N}\$i&Vi
3go!P])
(querySentence); ~?[@KK
count = ((Integer)query.iterate().next F(@|p]3*
p,ZubRJ"
()).intValue(); l+YpRx/T\
return count; - +
$u
} w 7=Y_
&)\0mpLK9
/* (non-Javadoc) JJ7-$h'0q
* @see com.adt.dao.UserDAO#getUserByPage QD /| zi
p~=%CG^5
(org.flyware.util.page.Page) 8(uxz84ce
*/ c67O/ B(
publicList getUserByPage(Page page)throws 1z[WJ}$u
6RzTSb
HibernateException { 0~n=|3*P
String querySentence = "FROM user in class CBi
V':;
Ig5J_Z^]b
com.adt.po.User"; }5DyNfZ]+0
Query query = getSession().createQuery (Rs<'1+>
\<;/)!Nmw
(querySentence); O^sgUT1O
query.setFirstResult(page.getBeginIndex()) p&XbXg-
.setMaxResults(page.getEveryPage()); "FG6R'
return query.list(); VWbgusxJ
} % J+'7'g
^R K[-tVV
} "$
u"Py
+J.^JXyp0
5l{_E:.1
I>ofSaN
e|Lh~sVq
至此,一个完整的分页程序完成。前台的只需要调用 NaAq^F U
uQpV1o5iA
userManager.listUser(page)即可得到一个Page对象和结果集对象 _Se>X=
Xo]FOJ5
的综合体,而传入的参数page对象则可以由前台传入,如果用 d{9jd{
_#G
6,cyi|s
webwork,甚至可以直接在配置文件中指定。 w3,QT}W vY
S{fNeK
下面给出一个webwork调用示例: c3K(mM:
java代码: E/5w
H/
GAz;4pUZ
(8H
"'
/*Created on 2005-6-17*/ |urohua
package com.adt.action.user; >Q"eaJxE!l
kk^KaD4dA
import java.util.List; sA}=o.\j:
Q,)G_lO
import org.apache.commons.logging.Log; Yckl,g_
import org.apache.commons.logging.LogFactory; srg#<oH|{c
import org.flyware.util.page.Page; C]eb=rw$
P#76ehR]K
import com.adt.bo.Result; shP,-Vs#
import com.adt.service.UserService; 5 _] i==M
import com.opensymphony.xwork.Action; ydoCoD
w
u~a<Psp&|
/** ob-be2EysH
* @author Joa `?`\!uP"
*/ 97<Y.
0
publicclass ListUser implementsAction{ w[]7{D];
+O\6p
privatestaticfinal Log logger = LogFactory.getLog U_oMR$/Z
l_QpPo!a
(ListUser.class); |bB..b
9>[$;>
private UserService userService; #J1a `}x
s}/YcUK
private Page page; ]]9eUw=
se7_:0+w
privateList users; ow]n)Te
B#sc!eLmU&
/* qmJFXnf
* (non-Javadoc) u3"F7
lJ
* X8?|5$Ey
* @see com.opensymphony.xwork.Action#execute() 4sROMk=l
*/ =}_c=z?UY
publicString execute()throwsException{ *i)GoQoB
Result result = userService.listUser(page);
"&v?>
page = result.getPage(); I,t 0X)
users = result.getContent(); GRlA9Q
return SUCCESS; 6t*=.b,N
} 8fZ\})t
qdO^)uJJ
/** %qN8uQx
* @return Returns the page. !4-NbtT
*/ Z#^2F8,]
public Page getPage(){ &W|'rA'r
return page; )3z.{.F
}
31J7# S2
)lH?XpfTjm
/** 6n;ew l}
* @return Returns the users. @(Q4
*/ &X +@,!
publicList getUsers(){ sOVaQ&+y
return users; Lf7iOW9U3
} ,]20I _
PP$Ig2Q
/** $"x(:
* @param page 4!iS"QH?;^
* The page to set. oLB pG1Va
*/ WMl_$Fd6
publicvoid setPage(Page page){ $c f?`k
this.page = page; }RW4
} BOfO$J}
YHCXVu<.b
/** \h_hd%'G
* @param users ${e(#bvGZ
* The users to set. tHhY1[A8m
*/ 9$S2:2(G
publicvoid setUsers(List users){ 0*q~(.>a
this.users = users; @AVx4,!>[
} ,CwhpW\Y
b\H(Lq17
/** bncK8SK
* @param userService 4zfgtg(
* The userService to set. AB+Zc
]
*/ Cg )#B+
publicvoid setUserService(UserService userService){ _czLKbcF
this.userService = userService; u%v^(9z
} 0-FwHDxw
} ;
Sh|6
f~W.i]
'6
w|z^
zCPjuS/~
Q
1NJ*EzJ~?
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, Ya\G/R
_%<7!|"
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 b*.)m
#v~zf@<KLB
么只需要: |!IJ/ivEgw
java代码: d5sGt#
BWw7o{d
|%zhwDQ.
<?xml version="1.0"?> lWnV{/q\X
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork TSE(Kt
C8NbxP
1.0//EN" "http://www.opensymphony.com/xwork/xwork- yHT}rRS8
tk_y~-xz
1.0.dtd"> o&I0*~sN
y]cx}9~
<xwork> /j3oHi$
vR+(7^Yy
<package name="user" extends="webwork- MQR2UK(
VAq(
t
interceptors"> F
\} Kh3
z XVQLz5
<!-- The default interceptor stack name q@Q|oB0W$)
:gQc@)jZ(*
--> kl2]#G(
<default-interceptor-ref x40R)Led
Mzxz- cE
name="myDefaultWebStack"/> MZ0uc2L=
0r+-}5aSl5
<action name="listUser" d7KeJ$xy}p
y0A2{'w
class="com.adt.action.user.ListUser"> Z AZQFr'*
<param B[b'OtH
i?*&1i@
name="page.everyPage">10</param> 2LD4f[a;
<result )
e;F@o3
j-yD;N
name="success">/user/user_list.jsp</result> MZL~IX
</action> /[{?zS{
Td8'z'
</package> t(}&<<1Bz
wiwJD}3h'
</xwork> KHF5Nt
<<n8 P5pXt
F!a YK2
~{+J~5!;<H
t7)Y@gRy
S :(1=@
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 qJISB7F[%O
^Ko0zz|R/
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。 %}$6#5"';
|fRajuA;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )xTp7YnZ;
bh+R9~
ed\,FWR
'7_'s1
_^&oNm1
我写的一个用于分页的类,用了泛型了,hoho NK"y@)%0
QRt(?96
java代码: }14.u&4
]G|@F
:
"q]v2t
package com.intokr.util; u45e>F=
V|b?H6Q
import java.util.List; B=n]N+
/dWuHS
/** _KD(V2W
* 用于分页的类<br> ijoR(R^r
* 可以用于传递查询的结果也可以用于传送查询的参数<br> +86\&y)
* .:<c[EJ
b
* @version 0.01 dcXtT3,kpX
* @author cheng i37W^9 R
*/ !pDS*{)E
public class Paginator<E> { D0"+E*
privateint count = 0; // 总记录数 CsuSg*#X+
privateint p = 1; // 页编号 H<1C5-
privateint num = 20; // 每页的记录数 :()4eK/\
privateList<E> results = null; // 结果 wBeOMA
&dOV0y_
/** Q[~O`Lz
* 结果总数 p&ow\AO
*/ P#EqeO
publicint getCount(){ 'n>|jw)
return count; %f:'A%'Qb
} yChC&kX
Z+
7a@V2cr@
publicvoid setCount(int count){ ,ew<T{PL
this.count = count; ",~3&wx
} EE%OD~u&9#
IP{Cj=
/** Bv9;q3]z-
* 本结果所在的页码,从1开始 -B`;Sx
* &s]
s]V)
* @return Returns the pageNo. xn6E f"
*/ QjZ}*p
publicint getP(){ #!,xjd
return p; ,pAMQ5
} [ >vS+G
y& Dd
/** 8mCr6$|%
* if(p<=0) p=1 %*jpQOw
* XWB>'
UDQ#
* @param p tQ|b?3
*/ ]JhtO{
publicvoid setP(int p){ a"WnBdFZ
if(p <= 0) ~vF.k,
p = 1; q*'hSt@+D
this.p = p; 4)XN1r:
} lg!1q8
.|iUDp6vz
/** T-<^mX[}
* 每页记录数量
;$|+H"g|
*/ ?Bh}
publicint getNum(){ t^h>~o'\
return num; VfZ/SByh7p
} 2\s-4H|
q
yn%w'
/** co~TQpy^
* if(num<1) num=1 <(^-o4Cl
*/ ^2=Jv.2{|
publicvoid setNum(int num){ mTs[3opg
if(num < 1) uO":\<1#
num = 1; L(8Q%oX%o
this.num = num; h\.UUC&<
} wx57dm+
MhJ`>.z1
/** XP(q=Mw
* 获得总页数 8PQ$X2)
*/ $@K+yOq+u
publicint getPageNum(){ Y-,#3%bT;;
return(count - 1) / num + 1; f$H"|Mbe
} FE_n+^|k<
1TbKnmTx
/** |
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* 获得本页的开始编号,为 (p-1)*num+1 xt3IR0
*/ ,xR^8G8
publicint getStart(){ $*2uI?87}:
return(p - 1) * num + 1; x#ouR+<
} Ebq5P$
]-ZD;kOr
/** y:W$~<E`p
* @return Returns the results. bk>M4l61
*/ w5&UG/z%l
publicList<E> getResults(){ q.g!WLiI
return results; M8g=t[\
} *XNvb ^<
c<4pu
public void setResults(List<E> results){ v4qvqGK
this.results = results; SS H/q/
} 8:0l5cZE
/}M@MbGM M
public String toString(){ H5qa7JMZ
StringBuilder buff = new StringBuilder f|b|\/.=
\(;5YCCE
(); E^|b3G6T
buff.append("{"); }Y-f+qX*
buff.append("count:").append(count); wuh$=fya
buff.append(",p:").append(p); Fa>Y]Y0r
buff.append(",nump:").append(num); @c{Z?>dUc#
buff.append(",results:").append 31bKgU{
"@Te!.~A.
(results); k_y@vW3
buff.append("}"); {&2$1p/9'
return buff.toString(); ETtK%%F0
} ls/:/x(5d
TuX#;!p6
} lSbAZ6
S:t7U%
0|NbU