Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 53d`+an2
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 L,ax^]
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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 pred{HEye
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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 Db;>MWt+e
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分页支持类: dvz6
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java代码: 0)7v_|z
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package com.javaeye.common.util; ~wOMT
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import java.util.List; eu~ u-}.
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publicclass PaginationSupport { @&%/<|4P5
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publicfinalstaticint PAGESIZE = 30; eVB43]g
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privateint pageSize = PAGESIZE; XKDX*x G
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privateList items; (I(U23A~
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privateint totalCount; b\zq,0%
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privateint[] indexes = newint[0]; )?$@cvf
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privateint startIndex = 0; cLvnLaA}
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public PaginationSupport(List items, int i)$+#N
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totalCount){ PRx- 0S
setPageSize(PAGESIZE); CfD4m,6
setTotalCount(totalCount);
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setItems(items); 5wE6 gRJ
setStartIndex(0); !q$>6P
} e'c3.sQ|?
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public PaginationSupport(List items, int 3Zs0W{OxU
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totalCount, int startIndex){ ^eefR5^_w
setPageSize(PAGESIZE); ;]=@;? 9
setTotalCount(totalCount); vb]uO ' l
setItems(items); w5rtYTI
setStartIndex(startIndex); .6y*Z+Zg
} Io>U-Zd\>
6W3."};
public PaginationSupport(List items, int i_+e&Bjd4j
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totalCount, int pageSize, int startIndex){ lw?C:-m
setPageSize(pageSize); $G9E=wn
setTotalCount(totalCount); T+rym8.p
setItems(items); ,KF>@3f
setStartIndex(startIndex); Zy{hYHQ
} SB5qm?pT8<
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publicList getItems(){ 5p:2gsk
return items; -]Mk}
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} <7B;_3/
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publicvoid setItems(List items){ G&MO(r}B
this.items = items; Z![#Uz.z
} 3-n&&<
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publicint getPageSize(){ NwQ$gDgu t
return pageSize; 3UZ_1nY
} 4`cf FowK~
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publicvoid setPageSize(int pageSize){ x^Qij!mB%
this.pageSize = pageSize; gvo5^O+)HH
} uH7rt
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publicint getTotalCount(){ J
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return totalCount; ;j(*:Nt1
} l^o>7 cM
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publicvoid setTotalCount(int totalCount){ a8%T*mk(
if(totalCount > 0){ +|K,\
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this.totalCount = totalCount; 8{{^pW?x
int count = totalCount / <5CQ#^cK
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pageSize; 66+]D4(k
if(totalCount % pageSize > 0) 9)j"|5H
count++; KBI1t$
indexes = newint[count]; t=p"nIE
for(int i = 0; i < count; i++){
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indexes = pageSize * FT}^Fi7
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i; /BF7N3
} L=s8em]7l
}else{ N "eK9>
this.totalCount = 0; >SYOtzg%
} -~lrv#5Q
} 6Q+VW_~
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publicint[] getIndexes(){ rfZg
return indexes; 4xFAFK~lx
} 5`K'2
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publicvoid setIndexes(int[] indexes){ Z vyF"4QN
this.indexes = indexes; pH@yE Vf
} Y!|};
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publicint getStartIndex(){ }:0HM8B7!
return startIndex; =umF C[.W
} lb"T'}q
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publicvoid setStartIndex(int startIndex){ AJRiwP|H+
if(totalCount <= 0) }2Im?Q
this.startIndex = 0; 8-K4*(-dL
elseif(startIndex >= totalCount) {z'Gg
this.startIndex = indexes YsO`1D
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[indexes.length - 1]; W^3'9nYU
elseif(startIndex < 0) : R8+jO
this.startIndex = 0; y92<(ziaX)
else{ )oS~ish
this.startIndex = indexes d{C8}U
jar?"o
[startIndex / pageSize]; mj9]M?]
} X<1ymb3
} [FWB
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publicint getNextIndex(){ -**fT?n
int nextIndex = getStartIndex() + rj5)b:c}
PKs$Q=Ol<|
pageSize; 0XL[4[LdA
if(nextIndex >= totalCount) i'#%t/ u
return getStartIndex(); z_z'3d.r7
else b1ZHfe:
return nextIndex; D[Ld=e8t
} (fO~nN{F
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publicint getPreviousIndex(){ $ g#d1u0q
int previousIndex = getStartIndex() - ZPY84)A_}
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pageSize; :!,.c$M
if(previousIndex < 0) 81wmKqDEs
return0; eA/}$.R
else a6op
return previousIndex; A?c?(~9O
} Gs}lw'pK
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} %,) Xi
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抽象业务类 %E2C4UbY
java代码: .>(qZEF
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/** .MRLAG
* Created on 2005-7-12 iWn7vv/t
*/ It^_?oiK
package com.javaeye.common.business; F=kiYa}
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import java.io.Serializable; JhB$s
import java.util.List; ?T_hK
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import org.hibernate.Criteria; P99s
import org.hibernate.HibernateException; m3_)UIJZ
import org.hibernate.Session; #DHeEE
import org.hibernate.criterion.DetachedCriteria; niM(0p
import org.hibernate.criterion.Projections; );x[1*e
import :SpPT
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org.springframework.orm.hibernate3.HibernateCallback; faI4`.i
import w~*"mZaG
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org.springframework.orm.hibernate3.support.HibernateDaoS _n<
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9}Zi_xK&|e
upport; E}=F
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import com.javaeye.common.util.PaginationSupport; &oiBMk`*
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public abstract class AbstractManager extends O<w7PS
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HibernateDaoSupport { >(a/K2$*1
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privateboolean cacheQueries = false; N&lKo}hk
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privateString queryCacheRegion; 9L9mi<,
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publicvoid setCacheQueries(boolean q0
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cacheQueries){ 4'#
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this.cacheQueries = cacheQueries; iD9hqiX&
} =t-503e.J
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publicvoid setQueryCacheRegion(String JTB5#S4W
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queryCacheRegion){ ]dIr;x`
this.queryCacheRegion = :J+GodW
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queryCacheRegion; uM~j
} .](s\6'
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publicvoid save(finalObject entity){ LHP?!rO0
getHibernateTemplate().save(entity); h9J
} n7Ia8?8-l
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publicvoid persist(finalObject entity){ jDc5p3D&[]
getHibernateTemplate().save(entity); wD&b[i
} J&6]3x
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publicvoid update(finalObject entity){ T/C1x9=?
getHibernateTemplate().update(entity); W1J7$
} V|fs"HY
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publicvoid delete(finalObject entity){ uJ$!lyJ6L
getHibernateTemplate().delete(entity); !xK`:[B
} Gwkp(9d
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publicObject load(finalClass entity, "$BWP
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finalSerializable id){ {GiR-q{t
return getHibernateTemplate().load Wc$1Re{z
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(entity, id);
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} "L" 6jT
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publicObject get(finalClass entity, oFV>b
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finalSerializable id){ X;0DQnAI8j
return getHibernateTemplate().get I(Yyg,1Z
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(entity, id); ~dK)U*Q
} IPnbR)[%
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publicList findAll(finalClass entity){ fW4N+2
return getHibernateTemplate().find("from f z8eL:i:
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" + entity.getName()); HIi5kv]}|
} Xu:Sh<:R
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publicList findByNamedQuery(finalString 3l 0>
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namedQuery){ ;HJ|)PN5L
return getHibernateTemplate g+k0Fw]!
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().findByNamedQuery(namedQuery); T!)v9L
} S:Ne g!`
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publicList findByNamedQuery(finalString query, l7P~_X_)"
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finalObject parameter){ X] &Q^
return getHibernateTemplate g%Ap <iT
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().findByNamedQuery(query, parameter); <gKT 7ONtg
} b^\u
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publicList findByNamedQuery(finalString query, ><[($Gq`g
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finalObject[] parameters){ Kuy,qZv!"
return getHibernateTemplate =?3D:k7z
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().findByNamedQuery(query, parameters); _}7N,Cx
} =x~HcsJ8!R
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publicList find(finalString query){ 0p_/eWww-
return getHibernateTemplate().find nj~1y')
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(query); ^~2GhveBV
} 0t1WvW
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publicList find(finalString query, finalObject 5/Q^p"
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parameter){ b$+.}&M
return getHibernateTemplate().find 0Q=4{*:?
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(query, parameter); w Maib3Q
} fNc3&=]]
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public PaginationSupport findPageByCriteria RUmJ=i'4/
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(final DetachedCriteria detachedCriteria){ }Z-]m
return findPageByCriteria hd.^ZD7
v3Y/D1jd"
(detachedCriteria, PaginationSupport.PAGESIZE, 0); *.AokY)_a
} 4QZ -7_
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public PaginationSupport findPageByCriteria &'UYV>
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(final DetachedCriteria detachedCriteria, finalint e/EfWwqt
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startIndex){ %^g BDlR^
return findPageByCriteria Y0=qn'`.
/z*?:*
(detachedCriteria, PaginationSupport.PAGESIZE, ,K8O<Mw8
}.O2xZ;}]'
startIndex); {b[8x
} 'QjX2ytgX
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public PaginationSupport findPageByCriteria *Y6BPFE*4
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(final DetachedCriteria detachedCriteria, finalint =m=`| Bn
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pageSize, 52BlFBNV
finalint startIndex){ 2Tt@2h_L
return(PaginationSupport) Bhl@\Kq
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getHibernateTemplate().execute(new HibernateCallback(){ 74rz~ZM
5
publicObject doInHibernate >z1RCQWju
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(Session session)throws HibernateException { T%Vii*?M
Criteria criteria = #vYdP#nWb
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detachedCriteria.getExecutableCriteria(session); Iw8;",e2
int totalCount = tB4- of3+
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((Integer) criteria.setProjection(Projections.rowCount
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? r=cLC
()).uniqueResult()).intValue(); )R+@vh#Q<$
criteria.setProjection W\o(f W
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(null); eXWiTi@
List items = _) 2fXG!
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criteria.setFirstResult(startIndex).setMaxResults =9GL;z:R+
0Np}O=>
(pageSize).list(); qC40/1-m8K
PaginationSupport ps = EX7cjQsml
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new PaginationSupport(items, totalCount, pageSize, B5aFt ;Vj
8'_>A5L/C
startIndex); MOY.$M,1
return ps; sXkWs2!
} %p)6m2Sb
}, true); 7\'vSHIL
} @;M( oFS9
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public List findAllByCriteria(final V=
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DetachedCriteria detachedCriteria){ ~sshhuF
return(List) getHibernateTemplate /cUcfe#X
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().execute(new HibernateCallback(){ ={-\)j
publicObject doInHibernate 0F6^[osqtl
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(Session session)throws HibernateException { y.26:c(
Criteria criteria = =O1N*'e
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detachedCriteria.getExecutableCriteria(session); k!b\qS~Q
return criteria.list(); Mb=vIk{Bf
} n;)!N
}, true); snOd
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} v-J*PB.0p
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public int getCountByCriteria(final >XjSVRO
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DetachedCriteria detachedCriteria){ *fso6j#%
Integer count = (Integer) (p'yya{(
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getHibernateTemplate().execute(new HibernateCallback(){ "]Wrir?l
publicObject doInHibernate +^YXqOXU
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(Session session)throws HibernateException { -bu.Ar-#;h
Criteria criteria = bv$_t)Xh
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detachedCriteria.getExecutableCriteria(session); '+N!3r{G
return 1w/1k6`0
}$s#H{T!
criteria.setProjection(Projections.rowCount \dTX%<5D
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()).uniqueResult(); rlmzbIuI9
} +',[q
}, true); E8zga )
return count.intValue(); /UTeaM!?"
} N}b/;Y
} kB{
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用户在web层构造查询条件detachedCriteria,和可选的 y{+$B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 h`X)sC+
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PaginationSupport的实例ps。 "i_I<?aGB
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ps.getItems()得到已分页好的结果集 S#6{4x4
ps.getIndexes()得到分页索引的数组 Fxdu)F,~u
ps.getTotalCount()得到总结果数 z %{Z
ps.getStartIndex()当前分页索引 O|=5+X
ps.getNextIndex()下一页索引 x1</%y5ev
ps.getPreviousIndex()上一页索引 56t9h/y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 5[}3j1
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 sS(t
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一下代码重构了。 =(:{>tO_"
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我把原本我的做法也提供出来供大家讨论吧: 8}z]B^?Fy
yH5^EY7rQ
首先,为了实现分页查询,我封装了一个Page类: 5S`_q&
java代码: XG FjqZr`
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/*Created on 2005-4-14*/ @zo}#.g
package org.flyware.util.page; GSo&$T;B6
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/** jN
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* @author Joa "&;8U.
* n " ?It
*/ FeOo;|a
publicclass Page { ,PC'xrEo
XCr\Y`,Z@
/** imply if the page has previous page */ gv)F`uRWA
privateboolean hasPrePage; 4Gz5Ju
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/** imply if the page has next page */ FN jT?*
privateboolean hasNextPage; Cq\1t
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/** the number of every page */ =OY&;d!C
privateint everyPage; z{XN1'/V
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Qt3%
/** the total page number */ )c|S)iJ7=z
privateint totalPage; V@krw"vW
XJJdCv^
/** the number of current page */ ms9zp?M
privateint currentPage; !_EL{ /ko
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/** the begin index of the records by the current {6H%4n
GP=i6I6C
query */ |m{Q_zAB
privateint beginIndex; 8 Z|c!QIU
4#hDt^N~
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/** The default constructor */ \i1>/`F
public Page(){ &q~**^;'
}#0MJ6L
} 4HXqRFUD
|]=. ^
/** construct the page by everyPage i
T* !3
* @param everyPage ]j.=zQP?'
* */ j{}-zQ]n
public Page(int everyPage){ A8Z2o\+
this.everyPage = everyPage; Cwo(%Wc
} 9{&APxm
ttQX3rmF01
/** The whole constructor */ i>=d7'oR
public Page(boolean hasPrePage, boolean hasNextPage, "p]F q,
+!_?f'kv`
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int everyPage, int totalPage, @L?X}'0xI4
int currentPage, int beginIndex){ cfZG3"
this.hasPrePage = hasPrePage; KKMzhvf]#
this.hasNextPage = hasNextPage; epz'GN]V
this.everyPage = everyPage; 85;hs
this.totalPage = totalPage; Q
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this.currentPage = currentPage; nT7{`aaQl
this.beginIndex = beginIndex; [HEqMBX=;
} $xx5+A%,
38Rod]\E
/** $7Sbz&)y3
* @return si`{>e~`6P
* Returns the beginIndex. @q=l H
*=
*/ WY=RJe2
publicint getBeginIndex(){ _PTo!aJL
return beginIndex; 1|K>V;C
} #$\cRLPg
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/** [>`[1;a X
* @param beginIndex mX@Un9k
* The beginIndex to set. *7`N^e
*/ O_}ZSB8"
publicvoid setBeginIndex(int beginIndex){ FN$hEc!
this.beginIndex = beginIndex; 'vgO`
} NF?FEUoxz
,p(4OZz5,
/** sU7>q}!
* @return !8 3x,*O
* Returns the currentPage. i&cH
*/ @(:ah
publicint getCurrentPage(){ _ F0qqj
return currentPage; lHYu-}TNP
} ~&E|;\G
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/** 6k#H>zY,
* @param currentPage Effp^7 3
* The currentPage to set. F~Kd5-I@
*/ mtfyhFk
publicvoid setCurrentPage(int currentPage){ to0tH^pD
this.currentPage = currentPage; %9_wDfw~
} jgiP2k[Xom
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/** m wuFXu/
* @return )9,*s!)9
* Returns the everyPage. 2>{_O?UN
*/ \L#BAB6z
publicint getEveryPage(){ uj.~/W1,!
return everyPage; nMU#g])y)
} 3t(8uG<rL
47Y|1
/** Q37VhScs
* @param everyPage K#"@nVWJ.m
* The everyPage to set. eO,
*/ /)80@
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; //--r5Q
} &77]h%B>
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/** {Y5h*BD>
* @return my#qmI
* Returns the hasNextPage. Isq3YY
*/ CK
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publicboolean getHasNextPage(){ ]{9oB-;,
return hasNextPage; `Tzqvnn
} 5H6GZ:hp
l3aG#4jj
/** [7Nn%eZC
* @param hasNextPage UQ|zSalv,
* The hasNextPage to set. 7YRDQjg
*/ =q|fe%#
publicvoid setHasNextPage(boolean hasNextPage){ uTJi }4cw
this.hasNextPage = hasNextPage; D#%J||
} QN(f8t(
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/** #( nheL
* @return X$JO<@x
* Returns the hasPrePage. K{VF_S:
*/ BfOG e!Si
publicboolean getHasPrePage(){ =erA.u
return hasPrePage; Vvx(7p-GQ
} $"{V],:T
|
ADX}
/** XA])<dZ
* @param hasPrePage +DKrX
* The hasPrePage to set. rL URP2~
*/ y? [*qnPj
publicvoid setHasPrePage(boolean hasPrePage){ T[))ful
this.hasPrePage = hasPrePage; 0:G@a&Lr
} 1at$_\{.(
Fm}O,=
/** 81a&99k#
* @return Returns the totalPage. | -Di/.
* k;3P;@3,W
*/ ~QdwoeaD
publicint getTotalPage(){ hE:P'O1
return totalPage; ;hs:wLVa"
} 6\86E$f=h
'OGOT0(
/** PqcuSb6
* @param totalPage Tu_dkif'
* The totalPage to set. OxF\Hm)(
*/ ZNB*Azi
publicvoid setTotalPage(int totalPage){ +2oZB]GPL
this.totalPage = totalPage; \Y9=dE}
} ^J>28Q\S
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} gx[#@(
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|
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 RA[` Cp"
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个PageUtil,负责对Page对象进行构造: UO"8 I2rB
java代码: 5d}PrYa
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/*Created on 2005-4-14*/ ! #
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package org.flyware.util.page; v,>F0ofJ
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import org.apache.commons.logging.Log; 2|}p&~G(
import org.apache.commons.logging.LogFactory; =< CH( 4!
-I=}SZ
/** n+GC L+Mo
* @author Joa GWE`'V
* `ss]\46>
*/ 1rPeh{SZ
publicclass PageUtil { A#1y>k
!.t'3~dUf$
privatestaticfinal Log logger = LogFactory.getLog flLmZ1"
,A6*EJ\w
(PageUtil.class); tDN-I5q
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/** 0[3b,
* Use the origin page to create a new page b!.# `.
* @param page q=nMZVVlF(
* @param totalRecords rW\~s TH
* @return M2xUs
*/ aRG[F*BY
publicstatic Page createPage(Page page, int }= <!j5:
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totalRecords){ |9\Lv$VJ
return createPage(page.getEveryPage(), P;_dilG
BK /;HG
page.getCurrentPage(), totalRecords); ]hf4= gm
} {Zseu$c
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/** SiBbz4
* the basic page utils not including exception .`h+fqa
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handler i'5bPW
* @param everyPage d?{2A84S
* @param currentPage nVM`&azD
* @param totalRecords ', &MYm\
* @return page EEo+#
*/ eqf~5/Z
publicstatic Page createPage(int everyPage, int ^X;>?_Bk
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currentPage, int totalRecords){ ~Igo
8ykl
everyPage = getEveryPage(everyPage); 3}gK`1Nq1
currentPage = getCurrentPage(currentPage); hWW<]qzA,
int beginIndex = getBeginIndex(everyPage, #62ww-E~
p-6.:y
currentPage); >5gzo6j/
int totalPage = getTotalPage(everyPage, ixH7oWH#
PJ.jgN(r
totalRecords); V9bLm,DtT
boolean hasNextPage = hasNextPage(currentPage, 2M1mdkP3
.R"L$V$RU.
totalPage); 3gh^a;uC
boolean hasPrePage = hasPrePage(currentPage); W P&zF$
;$/G T
returnnew Page(hasPrePage, hasNextPage, SYwNx">Bq
everyPage, totalPage, `j$d(+Gv
currentPage, v%- V|L
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beginIndex); N{yZk"fq:6
} [P,nW/H
}.vy|^X
privatestaticint getEveryPage(int everyPage){ ?n+\T'f!
return everyPage == 0 ? 10 : everyPage; ?yb{DZ46
} 0A9cu,ZdUR
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privatestaticint getCurrentPage(int currentPage){ G<eJ0S
return currentPage == 0 ? 1 : currentPage; X9j+$X\j
} 'W*F[U*&HP
qsRh ihPX
privatestaticint getBeginIndex(int everyPage, int 5=986ci$U
q}i87a;m
currentPage){ "lZ<bG
return(currentPage - 1) * everyPage; dp70sA!JF
} "U.=A7r
wp*1HnWj8Y
privatestaticint getTotalPage(int everyPage, int 6KG 63`aQ
y|se^dn
totalRecords){ K=)R!e8
int totalPage = 0; pAuwSn#i
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if(totalRecords % everyPage == 0) L /> GYx
totalPage = totalRecords / everyPage; bl<7[J.
else oUSG`g^P(M
totalPage = totalRecords / everyPage + 1 ; /f<(K-o]
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return totalPage; %5gJ6>@6Z
} ?g4|EV-56
| hM)e*"
privatestaticboolean hasPrePage(int currentPage){ w#,v n8
return currentPage == 1 ? false : true; eb\`)MI/
} j.}V~Sp*
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privatestaticboolean hasNextPage(int currentPage, I+t38un%
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int totalPage){ {;DZ@2|
return currentPage == totalPage || totalPage == 2v1&%x:y#
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0 ? false : true; HPKyAcS\
} DG?\6Zh
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} y(h(mr
0 _}89:-
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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。 d<? :Q
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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 G5J ZB7C
no6]{qn=6
做法如下: F)ld@Ydk=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1/+r?F3
Q8cPKDB
的信息,和一个结果集List: VDjIs UUX
java代码: =w$"wzc
TbAdTmW
4$GRCq5N;
/*Created on 2005-6-13*/ v^_]W3K
package com.adt.bo; To%*)a
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import java.util.List; Rbc2g"]
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import org.flyware.util.page.Page; I jztj
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/** L9?/ -@M
* @author Joa OrJlHMz
*/ 4?M3#],'h
publicclass Result { MXJ9,U{<C'
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private Page page; l@/kPEh
MGKeD+=5
private List content; ~'QeN%qadP
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/** 9.OwH(Ax7
* The default constructor 9AddF*B
*/ -Dq:Y,%q
public Result(){ >AX~c
jo
super(); LI;Efy L
} .C;_4jE
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/** l(w vQO
* The constructor using fields P(gVF|J?
* \pD=Lv9
* @param page |}p}`Mb)a
* @param content VMye5 P
*/ /<7C[^h{-
public Result(Page page, List content){ !+DJhw&c,
this.page = page; CndgfOF
this.content = content; oSA*~ N:
} oTD-+MZn
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/** kAB+28A
* @return Returns the content. w Al}:|+n
*/ !MJe+.
publicList getContent(){ >AzWM
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return content; N>pmhskN?
} X:``{!~geo
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/** r2GK_$vd
* @return Returns the page. k8
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*/ 4`U0">gY
public Page getPage(){ Z 5)_B,E:X
return page; Vl 19Md
} ZG@M%|>
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gg
/** E<<p_hX8R
* @param content ?)'
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* The content to set. I& M36f
*/ [l':G ]
public void setContent(List content){ ![@T iM
this.content = content; EY)Gi`lK
} Rj}o4s2x
)W1(tEq59
/** mGe|8In
* @param page Z%+BWS3YqY
* The page to set. )XP#W|;
*/ V@v1a@=W
publicvoid setPage(Page page){ %0yS98']g
this.page = page; -*|:v67C&
} >sQ2@"y)s2
} 8VP"ydg-U
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nw0L1TP/J
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2. 编写业务逻辑接口,并实现它(UserManager, Re*|$r#
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UserManagerImpl) WHUT/:?f
java代码: jow7t\wk
[IX*sr
s) Cpi
/*Created on 2005-7-15*/ %M{k.FE(
package com.adt.service; Q !9HA[Ly
}iilzE4oH#
import net.sf.hibernate.HibernateException; \Z)#lF|^
4!l
sk:R
import org.flyware.util.page.Page; ?fK^&6pI
FXx.$W
import com.adt.bo.Result; q*6q}s3n
JbE?a[Eg?
/** E-~mOYea
* @author Joa iOT)0@f'
*/ =-$!:W~
publicinterface UserManager { OlMBMUR:
#B @X
public Result listUser(Page page)throws VpkD'<