Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 }u*@b10
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 w*R-E4S?2
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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 r{3`zqo
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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 \36;csu
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。 .BB:7+
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分页支持类: D{d$L9.
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java代码: av$_hEjo|D
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package com.javaeye.common.util; sN) .Jo
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import java.util.List; h*LL(ow5
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publicclass PaginationSupport { t'/;Z:
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publicfinalstaticint PAGESIZE = 30; (dt_ D
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privateint pageSize = PAGESIZE; 1^>g>bn_"
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privateList items; xa*gQ%+F
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privateint totalCount; )GKgK;=~
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privateint[] indexes = newint[0]; >^ar$T;Ys
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privateint startIndex = 0; qiryC7.E
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public PaginationSupport(List items, int 1iW9?=a"
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totalCount){ ymCIk/\
setPageSize(PAGESIZE); ~J{{n_G{
setTotalCount(totalCount); H?^#zj`Ex+
setItems(items); V-r<v1}M
setStartIndex(0); J0! E@
} 6EWB3.x19
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public PaginationSupport(List items, int BT#g?=n#`
}f'1x%RS^
totalCount, int startIndex){ @O @yJ{(I
setPageSize(PAGESIZE); ,#O8:s
setTotalCount(totalCount); ?C2;:ol
setItems(items); WkIV
setStartIndex(startIndex); vp9<.*h
} _7.y4zQJ
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public PaginationSupport(List items, int ay|{!MkQ
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totalCount, int pageSize, int startIndex){ *03/:q ^(
setPageSize(pageSize); s@iCfX U
setTotalCount(totalCount); *?"{T;4u~O
setItems(items); <BA&S
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setStartIndex(startIndex); 5z>\'a1U
} R u-rp^a
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publicList getItems(){ y]%,Y=%X
return items; cN>i3}fq
} =Q/>g6
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publicvoid setItems(List items){ _=x_"rzx
this.items = items; xB+H7Ya
} [wG%@0\
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publicint getPageSize(){ ]w_)Spo.
return pageSize; c/U6K
yiK
} @v=q,A8_
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publicvoid setPageSize(int pageSize){ VrxH6 Y
this.pageSize = pageSize; BAHx7x#(
} ~mU_`o
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publicint getTotalCount(){ 2f4c;YS
return totalCount; lHqx}n@e
} jy2nn:1#^
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publicvoid setTotalCount(int totalCount){ Af<>O$$6
if(totalCount > 0){ "6QMa,)D
this.totalCount = totalCount; d]`,}vi#E9
int count = totalCount / J,Ap9HJt
@E;pT3; )
pageSize; - S-1<xR
if(totalCount % pageSize > 0) S>E.*]_
count++; $'*BS
indexes = newint[count]; 3Q)>gh*
for(int i = 0; i < count; i++){ nWu4HFi
indexes = pageSize * elgQcJ99
j@!}r|-T
i; A,)ELVk1F
} EPRs%(w`
}else{ cvfAa#tq>
this.totalCount = 0; e8bJ]
} p]eD@3Wz
} V+z)B+
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publicint[] getIndexes(){ I!D*( >
return indexes; v{Vesf
} 3fTI&2:
$(=1A>40
publicvoid setIndexes(int[] indexes){ k;7.qhe:
this.indexes = indexes; mO.U)tL[
} I9>*Yy5RNS
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publicint getStartIndex(){ |9eY
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return startIndex; 2A+,. S_!x
} p\S3A(
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d
publicvoid setStartIndex(int startIndex){ ;i>E@
if(totalCount <= 0) |lV9?#!
this.startIndex = 0; W|U1AXU7/
elseif(startIndex >= totalCount) edx'p`%d5
this.startIndex = indexes n`xh/vGm#
E2D8s=r
[indexes.length - 1]; qw1J{xoHW
elseif(startIndex < 0) AAgA]OD,
this.startIndex = 0; >oDP(]YGg
else{ xS1|Z|&
this.startIndex = indexes e]?S-J' z
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[startIndex / pageSize]; {m:R v&T
} W^Y0>W~
} ;bE6Y]"Rz
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publicint getNextIndex(){ cU|jT8Q4H
int nextIndex = getStartIndex() + =U2n"du
DU8LU*q'
pageSize; S
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if(nextIndex >= totalCount) k1zt|
return getStartIndex(); U{(07GNm#
else aS G2K0
return nextIndex; ts>}>}@vc
} ulJYJ+CC!
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publicint getPreviousIndex(){ tb3fz")UC
int previousIndex = getStartIndex() - d.oFlT
^iS:mt
pageSize; vW3Zu B
if(previousIndex < 0) 4'&BpFDUb
return0; ><c5Humr
else HH@xnd
return previousIndex; K9'*q3z
} 8-YrmP2k
x`i`]6q
} S\gP= .G
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抽象业务类 [)vwg`]
java代码: Cq;d2u0)o$
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/** mXj Ljgc}
* Created on 2005-7-12 5N<v'6&=
*/ Z"Ni
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package com.javaeye.common.business; !5t 3Y
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import java.io.Serializable; F:GKnbY
import java.util.List; ~la04wR28
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import org.hibernate.Criteria; QC,(rB
import org.hibernate.HibernateException; KdsvZim0>
import org.hibernate.Session; "e<.
n
import org.hibernate.criterion.DetachedCriteria; l?_!eA
import org.hibernate.criterion.Projections; B?Sfcq-
import 1R9?[RE
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org.springframework.orm.hibernate3.HibernateCallback; /,$\H
import PGl-2Cr
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org.springframework.orm.hibernate3.support.HibernateDaoS "m;]6B."
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upport; K/m)f#
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import com.javaeye.common.util.PaginationSupport; chzR4"WZFt
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public abstract class AbstractManager extends E9 q;>)}
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HibernateDaoSupport { Am0C|(#Xm
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privateboolean cacheQueries = false; g_c)Ts(
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privateString queryCacheRegion; `h5eej&s(
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publicvoid setCacheQueries(boolean U*"cf>dB(
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cacheQueries){ Z1&GtM
this.cacheQueries = cacheQueries; k|Yv8+XT
} z T T
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publicvoid setQueryCacheRegion(String Q4LlToHn
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queryCacheRegion){ ^J~A+CEf"W
this.queryCacheRegion = TM}'XZ&
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queryCacheRegion; dN/ "1%9)
} l~!fQ$~
C!k9 JAa$Z
publicvoid save(finalObject entity){ yZ)aKwj%U
getHibernateTemplate().save(entity); |abst&yp
} U3+_'"
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publicvoid persist(finalObject entity){ q&dRh
getHibernateTemplate().save(entity); &zX 3
} C2=iZ`Z>T
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publicvoid update(finalObject entity){ 3kqV_Pjg
getHibernateTemplate().update(entity); xZ=FH>Y6'
} 8w8I:*
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publicvoid delete(finalObject entity){ 6`baQ!xc.
getHibernateTemplate().delete(entity); 6Vbv$ AU
} >{qK]xj
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publicObject load(finalClass entity, X$|TN+Ub
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finalSerializable id){ !:O/|.+Vmf
return getHibernateTemplate().load OV("mNh
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(entity, id); p@7i=hyt`p
} *(&ClUQQ
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publicObject get(finalClass entity, >yA,@%X
^8oc^LOa~2
finalSerializable id){ K
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return getHibernateTemplate().get -wRyMY_D
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(entity, id); P`3s\8[Q
} `\F%l?aY
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publicList findAll(finalClass entity){ g
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return getHibernateTemplate().find("from <.=#EV^i
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" + entity.getName()); <V:<x
} x\J;ZiWwW
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publicList findByNamedQuery(finalString ZkB6bji
zdjM%l);
namedQuery){ {~p7*j^0
return getHibernateTemplate "?eH=!
cR=94i=t
().findByNamedQuery(namedQuery); =yTa,PY
} i+X2M-[Ls
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publicList findByNamedQuery(finalString query, 0ve`
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finalObject parameter){ Y=:KM~2hv
return getHibernateTemplate o!=lBfI
/y9J)lx
().findByNamedQuery(query, parameter); i2FD1*=/?
} q1TW?\pjb:
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publicList findByNamedQuery(finalString query, .mT#%ex
txml*/zL
finalObject[] parameters){ x>^3]m
return getHibernateTemplate &vFqe,Z
Kl aZZJ
().findByNamedQuery(query, parameters); j
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} Jny)uo8
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publicList find(finalString query){ eg2U+g4
return getHibernateTemplate().find AvrL9D
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(query); vcw>v={x
} +dCDM1{_a
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publicList find(finalString query, finalObject mWli}j#
~&DB!6*
parameter){ a/QtJwIV
return getHibernateTemplate().find /UpD$,T|^|
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(query, parameter); 2JiAd*WK
} !EX?m }7
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public PaginationSupport findPageByCriteria U/X|i /
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(final DetachedCriteria detachedCriteria){ cebs.sF:
return findPageByCriteria gV"qV
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /ojO>Y[<
} Sa;<B:|
t;.^K\S4
public PaginationSupport findPageByCriteria @K$VV^wp
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(final DetachedCriteria detachedCriteria, finalint Lj&1K~U
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startIndex){ :DdBn.
return findPageByCriteria ]6t]m2~\
k_D4'(V:b
(detachedCriteria, PaginationSupport.PAGESIZE, 4<G?
7Wwp )D
startIndex); ~A`&/U
} HzRX$IKB3(
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public PaginationSupport findPageByCriteria E0"10Qbi
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(final DetachedCriteria detachedCriteria, finalint $J QWfGwR
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pageSize, Iv$:`7|crX
finalint startIndex){ q&XCX$N
return(PaginationSupport) M.ZEqV+k
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getHibernateTemplate().execute(new HibernateCallback(){ E?3 0J3S
publicObject doInHibernate m:)Z6
(Wd_G-da
(Session session)throws HibernateException { nu&_gF,{
Criteria criteria = 1t/dxB;
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detachedCriteria.getExecutableCriteria(session); q>_vE{UB
int totalCount = =n@F$/h
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((Integer) criteria.setProjection(Projections.rowCount ]y3pE}R
#TMm#?lC
()).uniqueResult()).intValue(); 9=t#5J#O
criteria.setProjection N\9}\Rk@
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(null); ^FP}
qW~;9
List items = ZCy`2Fir
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criteria.setFirstResult(startIndex).setMaxResults +kjzn]}f
]g{hhP3>
(pageSize).list(); }JRP,YNh
PaginationSupport ps = ecr886
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new PaginationSupport(items, totalCount, pageSize, L|&'jH)
$.H:8^W
startIndex); $/u1chf
return ps; -O'{:s~
} )!tCC-Cr
}, true); B\Xh3l]+j
} F-_%>KJS
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public List findAllByCriteria(final $o]r]#B+
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DetachedCriteria detachedCriteria){ ^vJ"-{
return(List) getHibernateTemplate `AWy!}8
YiD-F7hf.*
().execute(new HibernateCallback(){ 7FAIew\r
publicObject doInHibernate l B1#
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(Session session)throws HibernateException { z< z*Wz
Criteria criteria = 3pvYi<<D'
!X^Hi=aV
detachedCriteria.getExecutableCriteria(session); :6XguU
return criteria.list(); /\na;GI$
} M70c{s`w5
}, true); 94\t1fE
} 2ck4C/ h
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public int getCountByCriteria(final m23+kj)+VY
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DetachedCriteria detachedCriteria){ vu=me?m?(
Integer count = (Integer) Ck: 9gn
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getHibernateTemplate().execute(new HibernateCallback(){ O7%2v@j|8
publicObject doInHibernate >*I N
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(Session session)throws HibernateException { 7W"/N#G
Criteria criteria = x<)G( Xe*
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detachedCriteria.getExecutableCriteria(session); l71gf.4g
return 9Gca6e3
-
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criteria.setProjection(Projections.rowCount O`WIkBV!
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()).uniqueResult(); rz6uDJ"
} :p' VbQZ{
}, true); qz 9tr
return count.intValue(); ~3gru>qI&
} Y$g}XN*)E
} `-_N@E1'>
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用户在web层构造查询条件detachedCriteria,和可选的 '0:i<`qv#g
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 9}5K6aQ
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PaginationSupport的实例ps。 in<}fAro6
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ps.getItems()得到已分页好的结果集 P-CB;\
ps.getIndexes()得到分页索引的数组 . V$ps-t
ps.getTotalCount()得到总结果数 ~]BMrgn
ps.getStartIndex()当前分页索引 Bn?:w\%Ue
ps.getNextIndex()下一页索引 YzAFC11,
ps.getPreviousIndex()上一页索引 Po(]rQbE
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 HG%Z"d
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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 mf' ]O,
;
dd Q/
一下代码重构了。 S_v(S^x6
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我把原本我的做法也提供出来供大家讨论吧: !g>.i`
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首先,为了实现分页查询,我封装了一个Page类: &.Q8Mi
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java代码: ymWgf6r<
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/*Created on 2005-4-14*/ xY\0zQ
package org.flyware.util.page; auHFir8f
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/** e8}Ezy"^
* @author Joa MgJ36zM
* $Z?\>K0i
*/ #?[.JD51l
publicclass Page { `TtXZ[gP}
mM/i^zT
/** imply if the page has previous page */ |.P/:e9
privateboolean hasPrePage; Fl3#D7K
WKmbNvN^
/** imply if the page has next page */ Xf
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privateboolean hasNextPage; ,e`'4H
GX&b;N
/** the number of every page */ !:CJPM6j3
privateint everyPage; vyI%3+N@
,RxYd6
/** the total page number */ pFsc}R/0/8
privateint totalPage; ir16
}LP!)|E
/** the number of current page */ zf [`~g
privateint currentPage; 8FkFM^\1L
&v!WVa?
/** the begin index of the records by the current pV(lhDNoQ
wGsRS[
query */ Z5(enTy-
privateint beginIndex; Ad$n4Ze
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gRJfX%*F
/** The default constructor */ |o<8}Nja6
public Page(){ tMp=-"
RDM`9&V!jp
} b;GD/UI
3WY$WRv
/** construct the page by everyPage vuQ%dDxI
* @param everyPage -e u]:4
* */ !xIm2+:(
public Page(int everyPage){ Xz 4 x
this.everyPage = everyPage; lb*8G
} ww k
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/** The whole constructor */ Zm
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public Page(boolean hasPrePage, boolean hasNextPage, BV`- =wRC
a4i:|
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int everyPage, int totalPage, >q~l21dUi
int currentPage, int beginIndex){ ,Gk}"w
this.hasPrePage = hasPrePage; mTNVU@TY=
this.hasNextPage = hasNextPage; 2[fN\e{
this.everyPage = everyPage; MZJ]Dwt]
this.totalPage = totalPage; &w8)* T
this.currentPage = currentPage; p&-'|'![l
this.beginIndex = beginIndex; 'R<&d}@P*#
} f:B>zp;N
;Lm=dd@S:
/** '1^B+m
* @return 3jH \yXj
* Returns the beginIndex. k
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*/ ;a{ :%t
publicint getBeginIndex(){ J?UQJ&!@O
return beginIndex; )6KMHG
} wd(Hv
{%2v Gn
/** 6[E|
* @param beginIndex !QI\Fz?
* The beginIndex to set. 8vSse
*/ ^D`v3d
publicvoid setBeginIndex(int beginIndex){ W1B)]IHc
this.beginIndex = beginIndex; KOz(TZ?u
} 8X|r4otn4
l7{oi!
/** ^ci3F<?Q=
* @return >gwz,{
* Returns the currentPage. 5}$b0<em~
*/ !\8 ;d8
publicint getCurrentPage(){ VQ5nq'{v
return currentPage; 73#x|lY
} [YrHA~=U
0$+fkDf
/** G0O#/%%
* @param currentPage Vm}%ttTC
* The currentPage to set. mI*[>#q>
*/ oh"O07
publicvoid setCurrentPage(int currentPage){ h7*W*Bd
this.currentPage = currentPage; `Q3s4VEC
} |tR
OL9b
v:Tzv^
/** 1i:|3PA~
* @return %CUGm$nH
* Returns the everyPage. 'I;!pUfVp
*/ km^^T_ M/
publicint getEveryPage(){ ]lw|pvtd
return everyPage; AcI,N~~
} VvFC -r,=G
l\M_-:I+4
/** VhjM>(
* @param everyPage joKIrS0y
* The everyPage to set. Uw,2}yR
*/ ~8"8w(CG*I
publicvoid setEveryPage(int everyPage){ ay "'#[
this.everyPage = everyPage; r<F hY
} R8rfM?"W
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/** *BuUHjTv
* @return @/ZF` :
* Returns the hasNextPage. g;$Xq)Dd
*/ ?Kvl!F!`
publicboolean getHasNextPage(){ ae:zWk'!
return hasNextPage; }ENR{vz$A
} 8Og_W8
%AOja+
/** W^3uEm&l!)
* @param hasNextPage 322jR4QGr
* The hasNextPage to set. ]EwVpvTw
*/ |-V&O=!^+
publicvoid setHasNextPage(boolean hasNextPage){ JpsPNa
this.hasNextPage = hasNextPage; O+}qQNe<
} `wF8k{Pb
WD Fjp
/** pdJ/&ufh
* @return ;nC.fBu
* Returns the hasPrePage. =@k%&* Y?
*/ upj]6f"(
publicboolean getHasPrePage(){ .h0b~nI>>
return hasPrePage; &>e-(4Xu
} N2.AKH
:Mm3
gW)
/** zIP6\u
* @param hasPrePage k}
]T;|h]
* The hasPrePage to set. 5~mh'<:
*/ Z2im@c67{
publicvoid setHasPrePage(boolean hasPrePage){ ,`ZYvF^%
this.hasPrePage = hasPrePage; +)2s-A f-
} `tjH<
*tm0R> ?!
/** JXyM\}9-X
* @return Returns the totalPage. Qne/g}PD`
*
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*/ gTA%uRBa
publicint getTotalPage(){ 3%.#}O,(
return totalPage; It2" x;
} )M__
t5L
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/** dCj,b$
* @param totalPage pb#?l6x$+
* The totalPage to set. H[DUZ,J
*/ r}uz7}z %"
publicvoid setTotalPage(int totalPage){ #j *d^j&
this.totalPage = totalPage; ooUk O
} WVY\&|)$
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} 1"pw
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*N{emwIq
H\XP\4#u
XJLQ{
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 gY@N~'f;"
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7,
个PageUtil,负责对Page对象进行构造: {uGP&cS~(
java代码: 6oF7:lt
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2Ry1b+\
/*Created on 2005-4-14*/ &3yD_P_3
package org.flyware.util.page; %/9
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import org.apache.commons.logging.Log; IpP~Uz
import org.apache.commons.logging.LogFactory; Ug&,Y/tFw2
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/** 61xs%kxb..
* @author Joa rk)##)
* Q>n|^y6
*/ MNSbtT*^
publicclass PageUtil { (PfqRk1Y
>3c@x
privatestaticfinal Log logger = LogFactory.getLog cI=(\pC
bf9a1<\
(PageUtil.class); r2k2%nI-J
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/** A45A:hqs
* Use the origin page to create a new page ar:+;.n
* @param page byv[yGa`
* @param totalRecords dDF
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* @return Y5F]:gs@
*/ (
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publicstatic Page createPage(Page page, int vap,y $C
sP ls
zC[
totalRecords){ +|tC'gCnV
return createPage(page.getEveryPage(), N 5 $c]E
=+AS/Jq
page.getCurrentPage(), totalRecords); Vb9',a?#n
} .nyfYa+
g55`A`5%C
/** h[PYP5{L
* the basic page utils not including exception }fKSqB]T-
+zy=50,
handler D}vmwg@3
* @param everyPage gB<3-J1R
* @param currentPage 9Lr'YRl[W
* @param totalRecords `3:.??7N
* @return page y
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*/ %Qj;, #z
publicstatic Page createPage(int everyPage, int %Q.&ZhB
ZcaX'5}!S
currentPage, int totalRecords){ F+@5C:<?
everyPage = getEveryPage(everyPage); t*?0D\b
2
currentPage = getCurrentPage(currentPage); %JLk$sP9y`
int beginIndex = getBeginIndex(everyPage, yrR1[aT
HeG)/W?r
currentPage); ` \+@Fwfx
int totalPage = getTotalPage(everyPage, -=(!g&0
*k19LI.5
totalRecords); e6!LS x}y
boolean hasNextPage = hasNextPage(currentPage, tz s</2
G,
yV"ZRrjO'Z
totalPage); G_SG
boolean hasPrePage = hasPrePage(currentPage); s&NX@
'D@-
returnnew Page(hasPrePage, hasNextPage, v$N|"o""
everyPage, totalPage, @WI2hHD
currentPage, &9Xhl''
Mb]rY>B4
beginIndex); ahPoEh
} ?.YOI.U^
sq;s]@~
privatestaticint getEveryPage(int everyPage){ Ybn`3
return everyPage == 0 ? 10 : everyPage; N&M~0iw
} Yh>]-SCw
7[.6axL
privatestaticint getCurrentPage(int currentPage){ `P9XqWr
return currentPage == 0 ? 1 : currentPage; K3=3~uY
} 6qp%$>$Vt;
[/X4"D-uOK
privatestaticint getBeginIndex(int everyPage, int -e8}Pm
"
Hbpqyl%O>
currentPage){ v.]Q$q^
return(currentPage - 1) * everyPage; l\s U
} 3JVK
V<j.xd7
privatestaticint getTotalPage(int everyPage, int ,13Lq-
65Cg]Dt71
totalRecords){ R%'^ gFk8
int totalPage = 0; [3@):8
A$w4PVS
if(totalRecords % everyPage == 0) !U5Wr+83
totalPage = totalRecords / everyPage; ,%)6jYHR w
else T,VY.ep/
totalPage = totalRecords / everyPage + 1 ; &cu lbcz
)4&cph';
return totalPage; -UD\;D?$
} oIefw:FE,a
;vIrGZV<
privatestaticboolean hasPrePage(int currentPage){ Y_QH&GZ
return currentPage == 1 ? false : true; [3!~PR]
} d.P\fPSD
u07pq4Ly
privatestaticboolean hasNextPage(int currentPage, zA1lca0HK
-*XCxU'
int totalPage){ nI*v820,
return currentPage == totalPage || totalPage == rW0FA
'UYR5Y>
0 ? false : true; kbMYMx.[
} $bsG]
]X^rU`":
t8dm)s[r8
} IqD_GL)Ms
M-giR:,
AqV7\gdOC
|0%+wB
X3V'Cy/sy
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 fF V!)Zj
OdB?_.+$
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 f4PIoZ e
?'<nx{!c
做法如下: G 8V,
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 `YIf_a{
Iwc{R8BV
的信息,和一个结果集List: GPGm]G t
java代码:
4A2?Uhpy
o!!yd8~*r
0eS)&GdR
/*Created on 2005-6-13*/ pb=cBZ$
package com.adt.bo; 7__Q1>o
$]A/
o(
import java.util.List; uECsh2Uin
Gqy,u3lE
import org.flyware.util.page.Page; yfC^x%d7G
1hziXC0WY
/** th&[Nt7
* @author Joa P[k$vD
*/ QJ7L7S
publicclass Result { l!g]a2x*
$.[#0lCI
private Page page; pe{;~-|6
a@0BBihz
private List content; 6%VV,$p
gw}Mw
/** :bC40@
* The default constructor Z>^pCc\lH
*/ `2PLWo
public Result(){ <E0UK^-}
super(); C,.Ee3T
} *Otg*,\
mI>,.&eo
/** -P]sRl3O;
* The constructor using fields 2[r^M'J
* [Ts"OPb%~
* @param page hjQ~uqbg
* @param content I*`* Q$
*/ 8{Fsm;UsY
public Result(Page page, List content){ dH^ <t,v
this.page = page; ,-OCc!7K
this.content = content; ~fo6*g:f1
} ]Qe{e3p;
b@2J]Ay E*
/** w-0mzk"
* @return Returns the content. q=9`06
*/ zD?K>I =
publicList getContent(){ Iy6$7~
return content; //4Xq8y
} g{P%s'%*
P8?Fm`
/** fa<v0vb+
* @return Returns the page. eEn;!RS)
*/ V}zEK0n(6
public Page getPage(){ p+Y>F\r&w
return page; <dvy"Dx
} +
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Zw~+Pb
/** wX*K]VMn
* @param content :,DM*zBVp
* The content to set. Q
pmsOp|
*/ E=#0I]v[
public void setContent(List content){ %bdjBa}
this.content = content; "1-}A(X
} _IdRF5<4
HWVtop/
/** >N.]|\V
* @param page L*x[?x;)@
* The page to set. \2vg{
*/ FEJ~k1z
publicvoid setPage(Page page){ EMc;^ d
this.page = page; DK
oN}c
} E.U_W
} O/!bG~\Y
Tr#V*.x
5P'p2x#U
c-Pw]Ju
:hI@AA>g
2. 编写业务逻辑接口,并实现它(UserManager, QzAK##9bfa
=dx1/4bZl|
UserManagerImpl) !XzF67
java代码: > z^#
V._(q^
Ii:>xuF&
/*Created on 2005-7-15*/ {iq3|x2[ :
package com.adt.service; -<_Ww\%8M
?SC[G-b
import net.sf.hibernate.HibernateException; #-GJ&m8
XduV+$03
import org.flyware.util.page.Page; E(i[o?
EFc-foN
import com.adt.bo.Result; O%ug@& S{
W\L`5CW
/** "ax..Mh\y
* @author Joa <u=4*:QE
*/ |> _!eS\=<
publicinterface UserManager { >pr=|$zk=
dqX;#H}h
public Result listUser(Page page)throws X~xd/M=9^
Jx=hJ-FY
HibernateException; 2mq$H_
A Z{^o4<q
} #"49fMi/
~I(Hc.Q
x+G0J8cW
9RWkm%?
-$,%f?
java代码: 10#f`OPC
(4%YHS8
Ve/xnn]'
/*Created on 2005-7-15*/
PTS]7
package com.adt.service.impl; 8+Bu+|c%f
OK{xuX8u
import java.util.List; ^`D=GF^tX
L.=w?%:H=
import net.sf.hibernate.HibernateException; u1c%T@w>Lz
U-^[lWn[@4
import org.flyware.util.page.Page; E~kG2x{a
import org.flyware.util.page.PageUtil; _0 m\[t.
)=DGdIEt
import com.adt.bo.Result; z~\t|Z]G,|
import com.adt.dao.UserDAO; )H}#A#ovj7
import com.adt.exception.ObjectNotFoundException; SZ_V^UX_
import com.adt.service.UserManager; cGwf!hA
p)~lL
/** Tb1U^E:
* @author Joa wap3Kd>MP
*/ _e7-zg$/
publicclass UserManagerImpl implements UserManager { [qoXMuC|P
dgo3'ZO
private UserDAO userDAO; 2:LHy[{5
_qWliw:0#
/** Gc$gJnQio
* @param userDAO The userDAO to set. WX4;l(PL=
*/ y4Er@8I`
publicvoid setUserDAO(UserDAO userDAO){ vsj3
this.userDAO = userDAO;
ayBRWT0
} AE@NOM7u
Urgtg37
/* (non-Javadoc) TH &qX
* @see com.adt.service.UserManager#listUser ++Ww88820
e2-Dq]p
(org.flyware.util.page.Page) wJlX4cT4YV
*/ pN&c(=If
public Result listUser(Page page)throws m~'? /!!
D.%B$Y;G
HibernateException, ObjectNotFoundException { :L
3&FA
int totalRecords = userDAO.getUserCount(); sFDG)
if(totalRecords == 0) W~Z<1[
throw new ObjectNotFoundException a83g\c5
<*EZ@XoN>
("userNotExist"); n$(p-po
page = PageUtil.createPage(page, totalRecords); 8by@iQ
List users = userDAO.getUserByPage(page); Y$-3v.
returnnew Result(page, users); 9,]5v+
} ?tg
y|
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} k6Cn"2q <
H7[6yh
/b;K
j!z-)p8hy
C_LvZ=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 aJqeD'\>
_e!F~V.
询,接下来编写UserDAO的代码: i5F:r|
3. UserDAO 和 UserDAOImpl: *xR
2)u
java代码: rNl.7O9b
j'p1q
+([!A6:
/*Created on 2005-7-15*/ yGpz,X4x
package com.adt.dao; y]e> E
=xianQ<lK
import java.util.List; M|io4+sy
OU7 %V)X5
import org.flyware.util.page.Page; y }08~L?2
0D~ C
5}/4
import net.sf.hibernate.HibernateException; tD$lNh^
2-0$FQ@/
/** c6Q(Ygc
* @author Joa Ejq#~Zhr!
*/ kVS?RHR
publicinterface UserDAO extends BaseDAO { Ov82ibp_1
s0hBbL0DH
publicList getUserByName(String name)throws ;o<m}bGaT
Tx%VU8\?n
HibernateException; b @;.F!x
pe&UQ C^
publicint getUserCount()throws HibernateException; ]=F8p2w?
fMf&?`V
publicList getUserByPage(Page page)throws kJ)gP 2E
9TxyZL
HibernateException; as"N=\N
4O{Avt7C
} nkeI60
B
?%L
cyd~2\Kv~
qO`qJ/
C0x"pO7
java代码: /OGA$eP
9x`4RE
rSVgWr8
/*Created on 2005-7-15*/ !Ngw\@f
package com.adt.dao.impl; KbxR
Lx]w
xU9@$am
import java.util.List; AN9[G
5c-N0@\
import org.flyware.util.page.Page; (S^ck%]]a!
?PPZp6A3L=
import net.sf.hibernate.HibernateException; v@EQ^C2.&
import net.sf.hibernate.Query; UmK X*T9
99iUOw c
import com.adt.dao.UserDAO; hh.Q\qhubB
,7d|O}B
/** o`r(`6@
* @author Joa YTyX`Y#
*/ +iF
1sC_
public class UserDAOImpl extends BaseDAOHibernateImpl #^mqQRpgq
1x >iz
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implements UserDAO { KhM.Tc
:]eb<J
/* (non-Javadoc) Bo\D.a(T
* @see com.adt.dao.UserDAO#getUserByName 2>hz_o{5',
.\5$MIF
(java.lang.String) (%<' A
*/ ]re'LC!d
publicList getUserByName(String name)throws %c6E-4b
"<l<&
qp
HibernateException { G5'_a$
String querySentence = "FROM user in class ]7qiUdxt:
fUcLfnr
com.adt.po.User WHERE user.name=:name"; @Z\~
Query query = getSession().createQuery S]2 {ZDP
9XV^z*E(J
(querySentence); IjZ@U%g@;
query.setParameter("name", name); !Ua&0s%
return query.list(); 0\a8}b||
} [N|xzMe
!0fI"3P@r
/* (non-Javadoc) x,Y5U+]E
* @see com.adt.dao.UserDAO#getUserCount() |pWaBh|r
*/ # .q#OC
publicint getUserCount()throws HibernateException { u.6P-yh
int count = 0; jM__{z
String querySentence = "SELECT count(*) FROM x0Bw{>Q
,86K
user in class com.adt.po.User"; /)V4k:#b
Query query = getSession().createQuery fA8ozL T
uu}-"/<~7
(querySentence); wRVD_?
count = ((Integer)query.iterate().next 30 7fBa
^Omfe
()).intValue(); \{PNw F?
return count; <d@pmh
} {j6g@Vd6lx
-i_En^Fi
/* (non-Javadoc) ~b8a^6:R"
* @see com.adt.dao.UserDAO#getUserByPage ]C *10S`
Q\#UWsN(T/
(org.flyware.util.page.Page) NJ$e6$g)
*/ _bI+QC#
publicList getUserByPage(Page page)throws S;}qLjT
If.n(t[M9
HibernateException { |%ZpatZA5
String querySentence = "FROM user in class fS./y=j(X
yDtOpM8<{
com.adt.po.User"; $pFk"]=
Query query = getSession().createQuery f9']
jJ+
6q%ed
UED
(querySentence); }aZrou3E
query.setFirstResult(page.getBeginIndex()) sb'p-Mj
.setMaxResults(page.getEveryPage()); _pSIJ3O
return query.list(); "=A|K~b
} B| Q6!
rl|Q)A{
} ~t9Mh^gij
KO-a; [/
MFTC6L+T
qeMv
Vf
od,tfLw4
至此,一个完整的分页程序完成。前台的只需要调用 p\+6"28{_~
~V$ f#X
userManager.listUser(page)即可得到一个Page对象和结果集对象 @"8~Y|L93
8_iHVc;<
的综合体,而传入的参数page对象则可以由前台传入,如果用 t F/nah
#>q[oie1e
webwork,甚至可以直接在配置文件中指定。 W uf/LKj
2v\W1VF
下面给出一个webwork调用示例: 9Dq.lr^
java代码: U_*3>Q
(rMZ
2f`xHI/@fj
/*Created on 2005-6-17*/ >a9l>9fyY
package com.adt.action.user; I Tn;m
qC.i6IL
import java.util.List; 0Bu*g LY
kJeu40oN
import org.apache.commons.logging.Log; 6J;i,/ky
import org.apache.commons.logging.LogFactory; h,hL?imD
import org.flyware.util.page.Page; 6EP~F8Kd
xOM_R2Md
import com.adt.bo.Result; i+RD]QL
import com.adt.service.UserService; *+~D+_,
import com.opensymphony.xwork.Action; ^;64!BaK
h60\ Y 8
/** -eq=4N=s
* @author Joa uWrFunh%
*/ UKYupLu5
publicclass ListUser implementsAction{ p5`ZyD]+
+3HPA#A
privatestaticfinal Log logger = LogFactory.getLog Gt5$6>A
Mz}i[|U\
(ListUser.class); +_-Y`O!Q
b_mWu@$
private UserService userService; 2*YP"Ryh
:}y| 4*z
private Page page; {9'hOi50
:f]!O@.~
privateList users; 7%YYr^d
kc|>Q7~{
/* QqjTLuN
* (non-Javadoc) ?N2X)Y@yi
* /KP_Vc:g2_
* @see com.opensymphony.xwork.Action#execute() b.,$# D{p
*/ L"9 Gc
publicString execute()throwsException{ 7 BK46x
Result result = userService.listUser(page); EaCZx
page = result.getPage(); {a@hRY_
users = result.getContent(); HIrEv
return SUCCESS; Hp*gv/0
} Es~DHX
-7,vtd[h
/** gb9[Meg'
* @return Returns the page. i&1U4q
*/ _&K\D
p&@
public Page getPage(){ gTuX *7w
return page; X-v~o/r7
} UCn.t
5{HtJ?sKc5
/** &R0OeRToUb
* @return Returns the users. ;h~?ko
*/ LEA;dSf
publicList getUsers(){ &E`9>&~J
return users; GP Ix@k
} tgK x 4
.oEFX8
/** EuLXtq
* @param page A
mvw`u>
* The page to set. 0|GpZuGO9
*/
a2[8wv1
publicvoid setPage(Page page){ b%<16 4i
this.page = page;
srvYAAE
} |
[p68v>
"zXGp7Q'#
/** Ys)+9yPPn
* @param users m^5s>hUl
* The users to set. /AoVl'R
*/ wd"TM
publicvoid setUsers(List users){ bD d_}
this.users = users; Plb}dID"
} 5nY9Ls(e
CN-4-
/** H
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* @param userService k RQ~hRT6
* The userService to set. 8~}s 3j4
*/ dRHlx QUn
publicvoid setUserService(UserService userService){ S\}?zlV
this.userService = userService; #i@ACAgn;6
} otoBb^Mz
} Q;=6ag'
#`r(zI[
+_P8'e%Iy
{WIY8B'c
<( cM*kV
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, n#)PvV~
C0P*D,
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 aX:#'eDB
jGJ.Pvc>i
么只需要: ;gdi=>S_
java代码: S!u6dz^[$X
dD :
T4Xtuu1
<?xml version="1.0"?> _r~!O$2
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork G OH
,0BR-#
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4c
;5-R=e(KA
1.0.dtd"> ]s f2"~v
zoJ_=- *s
<xwork> Wk7L:uK
_E3U.mV
<package name="user" extends="webwork- 0S%tsXt+
{qJHL;mP:8
interceptors"> mJSK; @w<O
@Q/x&BV
<!-- The default interceptor stack name G`9cd\^
\I'f3
--> +SAk:3.#CV
<default-interceptor-ref ~*jsB=XM/
(s5<
name="myDefaultWebStack"/> >6*(}L9
Y>xi|TWN
<action name="listUser" nXv 7OEpTx
XulaPq
class="com.adt.action.user.ListUser"> aytq4Ts
<param X!HDj<
I/oIcQS!k
name="page.everyPage">10</param> R5m`;hF
<result NG!>7$@RV
14mXx}O
name="success">/user/user_list.jsp</result> N>Vacc_[
</action> R.91v4J
Y')O>C0~
</package> fui4@
W`w5jk'0^=
</xwork> A4~D#V
"PZYgl
pESB Il
{E;2&d
Pz5ebhgq
IOSuaLH^
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 k&MlQ2'!<
?BWHr(J
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。 0@II&
(45NZBs
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 <QYCo1_
FE0qw1{qQ
HiQoRk
fBHkLRFH
= 4BLc
我写的一个用于分页的类,用了泛型了,hoho 73&]En
6V.awg,
java代码: 8#X?k/mzU
Qw3a"k-
6(ka"Vu~
package com.intokr.util; L@)b%Q@a
E}xz7u
import java.util.List; 3~cS}N T
h5LJijJ
/** 4RK.Il*d
* 用于分页的类<br> zAKq7'_=
* 可以用于传递查询的结果也可以用于传送查询的参数<br> >k$[hk*~
* @ChN_gd3!
* @version 0.01 mXxZM;P[
* @author cheng dNR7e
*/ r24\DvS
public class Paginator<E> { ZcUh[5:|
privateint count = 0; // 总记录数 V-?sek{;
privateint p = 1; // 页编号 P@gu~!
privateint num = 20; // 每页的记录数 8+*g4=ws
privateList<E> results = null; // 结果 DBu)xr}7A
EpFIKV!
/** ;J,,f1Vw
* 结果总数 g_rA_~dh
*/ e8~62O^
publicint getCount(){ 1?/5A|?V4+
return count; 30sC4}
} fK)ZJ_?w,@
y8<lp+
publicvoid setCount(int count){ c,6<7
this.count = count; sh',"S#=@
} &LCUoTzj
2 ||KP|5@
/** R-g>W
* 本结果所在的页码,从1开始 M!xm1-,[
* (hhdbf
* @return Returns the pageNo. 5@w'_#!)
*/ <Z\MZ&{k{*
publicint getP(){ C5:dO\?O
return p; [JX}1%NA
} vR6^n~
ef;&Y>/
/** 'DL;c@}37
* if(p<=0) p=1 zPX=MfF
* oyKt({
* @param p az:~{f*-
*/ ?:#>^eWYe7
publicvoid setP(int p){ +XU$GSw3(
if(p <= 0) xWC\954
p = 1; 1jZDw~
this.p = p; TS\A`{^T
} *3w/`R<\
_0DXQS\
/** beN>5coP%A
* 每页记录数量 "6`)vgI~
*/ wu&|~@_s@
publicint getNum(){ b6LC$"t0
return num; E]HND.`*>
} D+*uKldS;
gTmUK{y'
/** e 5WdK
* if(num<1) num=1 >6.[i@RmWU
*/ Xa? 6#
publicvoid setNum(int num){ )+jK0E1
if(num < 1) g9FVb7In_
num = 1; eI/\I:G{f
this.num = num; Rk437vQD,
} 2;Y@3d:z
[B2>*UPl
/** ;qT!fuN;
* 获得总页数 (!XYH@Mz<w
*/ JR?
)SGB
publicint getPageNum(){ i(&6ys5
return(count - 1) / num + 1; 'y+bx?3Z
} p5twL
NE=#5?6%g7
/** _Cv[`e.
* 获得本页的开始编号,为 (p-1)*num+1 *uI hxMX
*/ ^B&ahk
publicint getStart(){ 2-cU -i4
return(p - 1) * num + 1; 8ACYuN\
} \V"PmaP\
07T;IV3#C5
/** uDy>xJ|
* @return Returns the results. 9d,]_l.sB
*/ m>Z\
rqOK
publicList<E> getResults(){ V(''p{
return results; ig.6[5a\
} .^)C:XiW
LAK-!!0X
public void setResults(List<E> results){ !"Oj$c
-
this.results = results; ^?K?\
} 2d>d(^
:YRzI(4J
public String toString(){ U!;aM*67
StringBuilder buff = new StringBuilder "dLMBY~
(8@hF#N1
(); %_j?<h&
buff.append("{"); -NflaV~
buff.append("count:").append(count); 9(N)MT5F
buff.append(",p:").append(p); li3PR$W V
buff.append(",nump:").append(num); v'bd.eqw
buff.append(",results:").append Sf4h!ly
) v[Knp'
(results); {>UMw>T[
buff.append("}"); '^-4{Y^2E
return buff.toString(); -u3SsU)_%N
} cDQw`ORP*g
G0 nH Z6
} LDi ezi
o+X'(!Trw
Gwrx)Mq