Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :tWkK$
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "rdpA[>L
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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 +|C@B`h
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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 3MQHoxX
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分页支持类: fR1LVLU
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java代码: D;sG9Hky
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package com.javaeye.common.util; (-<hx~
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import java.util.List; Q g/Rw4[
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publicclass PaginationSupport { E8C8kH]
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publicfinalstaticint PAGESIZE = 30; w,hm_aDq
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privateint pageSize = PAGESIZE; ?;#Q3Y+
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privateList items; X#1WzWk'
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privateint totalCount; k;qS1[a
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privateint[] indexes = newint[0]; ll__A|JQ
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privateint startIndex = 0; -axKnfj
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public PaginationSupport(List items, int OX,em Ti
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totalCount){ r?KRK?I
setPageSize(PAGESIZE); F=5+JjrX
setTotalCount(totalCount); )]n>.ZmLCB
setItems(items); g Cp`J(2v:
setStartIndex(0);
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} Vc0j)3
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public PaginationSupport(List items, int <hzHrx'o{
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totalCount, int startIndex){ Zl[EpXlZ
setPageSize(PAGESIZE); "tT4Cb3
setTotalCount(totalCount); PU%Zay
setItems(items); S))B^).0-
setStartIndex(startIndex); *vQ 6LF;y
} =pzTB-G
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public PaginationSupport(List items, int z<Z0/a2'1
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totalCount, int pageSize, int startIndex){ uj;iE
9
setPageSize(pageSize); rHk(@T.]
setTotalCount(totalCount); :@p]~{m :G
setItems(items); A}! A*z<9
setStartIndex(startIndex); L@RnLaoQ
} &%v*%{|j
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publicList getItems(){ WiZkIZ
return items; ;{8 X+H
} XN-1`5:4I
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publicvoid setItems(List items){ iwIn3R,
this.items = items; $Ptl&0MN%
} C{U*{0}
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publicint getPageSize(){ =ZSYg K
return pageSize; .NWsr*Tel
} `]]m$
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publicvoid setPageSize(int pageSize){ =f@71D1
this.pageSize = pageSize; 2cu2S"r
} ZK?V{X{";
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publicint getTotalCount(){ Lww&[|k.
return totalCount; l`75BR
} }2Ge??!
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publicvoid setTotalCount(int totalCount){ t.&JPTK-H
if(totalCount > 0){ <=!t!_
this.totalCount = totalCount; {%6
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int count = totalCount / Ag3+z+uS
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pageSize; `4ga~Ch
if(totalCount % pageSize > 0) '"q+[zwv
count++; Li8/GoJW-T
indexes = newint[count]; fx:vhEX
for(int i = 0; i < count; i++){ b4$g$()
indexes = pageSize * 1A93ol=
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i; 2./z6jXW_
} EWl9rF@I
}else{ ">B&dNrt
this.totalCount = 0; |+~P; fG
} O*2{V]Y
@
} iYa)*,
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publicint[] getIndexes(){ A[4HD!9=
return indexes; F" G+/c/L
} BGNZE{K4"
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publicvoid setIndexes(int[] indexes){ o8g]ho
this.indexes = indexes; ]}S9KP
} "1dpv\
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publicint getStartIndex(){ +pUYFDwFx
return startIndex; lib^JJF
} (w_b
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publicvoid setStartIndex(int startIndex){ 'e>'JZR
if(totalCount <= 0) )MV `'i
this.startIndex = 0; ?mi}S${g
elseif(startIndex >= totalCount) `&)
this.startIndex = indexes 3]NKAPY
1)e[F#|
[indexes.length - 1]; lq1223
elseif(startIndex < 0) '[[IalQ?
this.startIndex = 0; Dir# [j
else{ "SKv'*\b
this.startIndex = indexes rIyIZWkI
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[startIndex / pageSize]; O|v8.3[cT
} t }K8{
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} JBV
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publicint getNextIndex(){ # b3 14
int nextIndex = getStartIndex() + ieO w&
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pageSize; (h&=Na~
if(nextIndex >= totalCount) }PMlG
return getStartIndex(); Qc Xw -
else R{B5{~m>W@
return nextIndex; !bW^G}
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} W9G jUswv!
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publicint getPreviousIndex(){ Kk \,q?
int previousIndex = getStartIndex() - *EU1`q*
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pageSize; !}d_$U$
if(previousIndex < 0) vN6)Szim
return0; (^ J2(
else 7*+tG7I @
return previousIndex; T[ zEAj
} \ 6Y%z
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} meD83,L~N
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抽象业务类 `j6O
java代码: k
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/** w\JTMS$
* Created on 2005-7-12 &61h*s
*/ -9 |)O:
package com.javaeye.common.business; rB =c
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import java.io.Serializable; ;A?86o'?
import java.util.List; AB.ZmR9|
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import org.hibernate.Criteria; {ZUgyGE{
import org.hibernate.HibernateException; 7%|HtBXv^
import org.hibernate.Session; TaG(sRI
import org.hibernate.criterion.DetachedCriteria; $3Sm?
import org.hibernate.criterion.Projections; @ +>>TGC
import nI`9|W
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org.springframework.orm.hibernate3.HibernateCallback; m4 c2WY6k
import vf!lhV-UG+
-+Ox/>k
org.springframework.orm.hibernate3.support.HibernateDaoS ocj^mxh=O
tY`%vI [
upport; :<6gP(
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import com.javaeye.common.util.PaginationSupport; wA";N=i=
xqj@T^y
public abstract class AbstractManager extends E**Hu 9
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HibernateDaoSupport { 69Q#UJ
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privateboolean cacheQueries = false; +qa^K%K
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privateString queryCacheRegion; D'
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publicvoid setCacheQueries(boolean /,9n1|FrG
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cacheQueries){ 'Y5l3xQk
this.cacheQueries = cacheQueries; %PM8;]
} WQNFHRfO*n
)jH|j
publicvoid setQueryCacheRegion(String %bB:I1V\
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queryCacheRegion){ :w9s bW
this.queryCacheRegion = 9d+z?J:
E>1%7"
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queryCacheRegion; hhJ>>G4R2
} :D
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publicvoid save(finalObject entity){ $mst\]&;
getHibernateTemplate().save(entity); Wl{}>F`W[
} sWMY
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publicvoid persist(finalObject entity){ Uclta
getHibernateTemplate().save(entity); KCS},X_
} NY%=6><t!
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publicvoid update(finalObject entity){
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getHibernateTemplate().update(entity); IoxdWQ4]A
} 9{R88f?;
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publicvoid delete(finalObject entity){ MgQb" qx
getHibernateTemplate().delete(entity); $$---Y
} :w26d-QR(
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publicObject load(finalClass entity, ;TCT%j`^o
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finalSerializable id){ 6;}W)S
return getHibernateTemplate().load 0?,%B?A8O
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(entity, id); C<q@C!A
} g:[yA{Eh
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publicObject get(finalClass entity, MMyJAGh
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finalSerializable id){ h~.z[
return getHibernateTemplate().get PLQLGb4f_;
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(entity, id); w*IDL0#
} $McbVn)~f
@<=<?T>1
publicList findAll(finalClass entity){ 0`kaT
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return getHibernateTemplate().find("from K7]+. f
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" + entity.getName()); F44KbUH
} hdy
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publicList findByNamedQuery(finalString 0)9'x)l:
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namedQuery){ aF:|MTC(~
return getHibernateTemplate ? VHOh9|AT
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().findByNamedQuery(namedQuery); J+f*D+x1
} G>j4b}e
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publicList findByNamedQuery(finalString query, -i"?2gK
f
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finalObject parameter){ kPFqsq
return getHibernateTemplate
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().findByNamedQuery(query, parameter); .#}`r`/
} 7G
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@LR :^>&*
publicList findByNamedQuery(finalString query, ^ub@Jwe
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finalObject[] parameters){ sB%QqFRP
return getHibernateTemplate vuNq7V*}
tF~D!t@
().findByNamedQuery(query, parameters); o_on/{qz
} "/$2oYNy+
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publicList find(finalString query){ H 5'Ke+4.e
return getHibernateTemplate().find rCgoU
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;
(query); QX|y};7\e
} :6y;U
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publicList find(finalString query, finalObject v0'`K 5M
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parameter){ I2<5#|CXpZ
return getHibernateTemplate().find >sm<$'vZ/
-)$5[jM]
(query, parameter); )~H&YINhn
} #Bi8>S
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public PaginationSupport findPageByCriteria [W*Q~Wvp
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(final DetachedCriteria detachedCriteria){ b]xE^zM-I`
return findPageByCriteria /zZ";4
O}mz@-Z
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7':qx}c#!1
} db5@+_
)|`|Usn#[
public PaginationSupport findPageByCriteria T6fm`uL&L
rJ)8KY>
(final DetachedCriteria detachedCriteria, finalint OVa38Aucr3
ZBl!7_[_
startIndex){ pkT26)aW
return findPageByCriteria \9T/%[r#
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(detachedCriteria, PaginationSupport.PAGESIZE, Hw
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startIndex); BoHpfx1C
} E7>D:BQ\2
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public PaginationSupport findPageByCriteria k{-#2Qz
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(final DetachedCriteria detachedCriteria, finalint k*uLjU
6Dz N.fz
pageSize, 9@yi
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finalint startIndex){ .p$tb2%r
return(PaginationSupport) { bD:OF
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getHibernateTemplate().execute(new HibernateCallback(){ U3b&/z|b?
publicObject doInHibernate }?^5L7n
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(Session session)throws HibernateException { :DoE_
Criteria criteria = w-wap
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detachedCriteria.getExecutableCriteria(session); 'jj|bN
int totalCount = II)
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((Integer) criteria.setProjection(Projections.rowCount 8m"jd+
'4]_~?&x
()).uniqueResult()).intValue(); =dDr:Y<@*
criteria.setProjection =@y
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(null); \zx$]|AQ
List items = |cIv&\ x
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criteria.setFirstResult(startIndex).setMaxResults \<0xg[
c01i!XS
(pageSize).list(); 5}NTqN0@
PaginationSupport ps = ;?.w!|6
> xie+ ^
new PaginationSupport(items, totalCount, pageSize, tv'=xDCp
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9lG.
startIndex); s5
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return ps; crl"Ec
} q!4eVg*
}, true); `|WEzW~
} p` /c&}
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public List findAllByCriteria(final :hFKmoy#
3:"w"0[K3
DetachedCriteria detachedCriteria){ ~Y 3X*
return(List) getHibernateTemplate i.Z iLDs\7
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().execute(new HibernateCallback(){ pi;'! d[l%
publicObject doInHibernate =:;K nS
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(Session session)throws HibernateException { ,jq:%Y[KZ
Criteria criteria = :b`ywSp`
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detachedCriteria.getExecutableCriteria(session); $L"h|>b\o
return criteria.list(); (C.<H6]=
} #6*20w_u
}, true); iOJ5KXrAO
} FW)VyVFmk
OAo;vC:^
public int getCountByCriteria(final 9>9,
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DetachedCriteria detachedCriteria){ 2uLBk<m5c
Integer count = (Integer) j06qr\Es
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getHibernateTemplate().execute(new HibernateCallback(){ za!8:(
publicObject doInHibernate r t'pc\|O&
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(Session session)throws HibernateException { kJK*wq]U6
Criteria criteria = YDYN#Ob(;
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detachedCriteria.getExecutableCriteria(session); gfJHB3@
return 8F9x2CM-[C
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criteria.setProjection(Projections.rowCount yS1i$[JV
NOFuX9/'w
()).uniqueResult(); apZPHau6h
} }inV)QQ
}, true); =z[$o9
return count.intValue(); 2{<o1x,Ym
} \![ p-mW{
} Q?>DbT6
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用户在web层构造查询条件detachedCriteria,和可选的 Zm*q V!
,ygUy]
startIndex,调用业务bean的相应findByCriteria方法,返回一个 89Ir}bCr
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PaginationSupport的实例ps。 nh*6`5yj
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ps.getItems()得到已分页好的结果集 a:Nf+t
ps.getIndexes()得到分页索引的数组 3,?LpdTS
ps.getTotalCount()得到总结果数 uHq;z{ 2GI
ps.getStartIndex()当前分页索引 8]D0)
ps.getNextIndex()下一页索引 P^AI*tH"m
ps.getPreviousIndex()上一页索引 1gQ_76Yck
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#>6Jsnv1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 SY.ZEJcv
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 zx5#eMD
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一下代码重构了。 G=]ox*BY
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我把原本我的做法也提供出来供大家讨论吧: ?dPr HSy
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首先,为了实现分页查询,我封装了一个Page类: e07u@_'^
java代码: >gDeuye
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/*Created on 2005-4-14*/ Dt!
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package org.flyware.util.page; (eAz
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7>=
/** 0SQrz$y
* @author Joa pHXs+Ysw+
* P\WFm
*/ <HtGp6q
publicclass Page { =R<92v
}2Tq[rl~s
/** imply if the page has previous page */ z'*"iaX<c
privateboolean hasPrePage; W1521:
ut#pg+#Q
/** imply if the page has next page */ 5mS/,fs@
privateboolean hasNextPage; y)"rh /;
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/** the number of every page */ n
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privateint everyPage; 2Z5_@Y
)|_L?q#w!'
/** the total page number */ a?yU;IKJ
privateint totalPage; r.lHlHl
Wm}gnNwA
/** the number of current page */ \E[6wB>uN%
privateint currentPage; e{9~m
r@/@b{=
/** the begin index of the records by the current Q :.i[
_a f $0!
query */ cUr!U\X[
privateint beginIndex; na|sKE;{
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@v#,SF {
/** The default constructor */ 7377g'jL
public Page(){ BeN]D
I\x9xJ4x
} 684d&\(s
>JAWcT)d
/** construct the page by everyPage &_u.q/~
* @param everyPage a#k7 aOT0
* */ ,i1BoG
public Page(int everyPage){ ^/6P~iK'
this.everyPage = everyPage; I)yF!E &
} r<4j;"lQK
C BoCT3@~
/** The whole constructor */ ,<Z,- 0S
public Page(boolean hasPrePage, boolean hasNextPage, \7%#4@;?
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nzaA_^`mB
int everyPage, int totalPage, iPkCuLQ}
int currentPage, int beginIndex){ :w!hkUx#
this.hasPrePage = hasPrePage; 9K#3JyW*
this.hasNextPage = hasNextPage; oR,6esA+6n
this.everyPage = everyPage; '
,S}X\
this.totalPage = totalPage; SZyORN
this.currentPage = currentPage; N#ZWW6
this.beginIndex = beginIndex; k}p8"'O
} r@m]#4
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/** Uqb]&2
* @return Dk>6PBl
* Returns the beginIndex. ca,W:9#.xn
*/ IRwtM'%0
publicint getBeginIndex(){ .izq}q*P
return beginIndex; #\`kg#&
} ZX64kk+
wMj#.Jh
/** M2N8?Ycv3
* @param beginIndex jz![#-G
* The beginIndex to set. g&85L$
*/ KN[;z2i
publicvoid setBeginIndex(int beginIndex){ !yxqOT-
this.beginIndex = beginIndex; ~bCA8
} C l,vBjl h
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/** vy*-"=J
* @return D%nd7
|
* Returns the currentPage. gFKJbjT|
*/ M:{Aq&.
publicint getCurrentPage(){ S,nELV~!
return currentPage; )-emSV0zE
} ]/H6%"CTa
/KX+'@
/** ($kw*H{Ah^
* @param currentPage \0d'y#Gp*
* The currentPage to set. ,aLwOmO
*/ )0iN2L]U;
publicvoid setCurrentPage(int currentPage){ .1jiANY
this.currentPage = currentPage; "GQ Q8rQ
} %^HE^ &
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/** y:}qoT_.
* @return TKv!wKI
* Returns the everyPage. a!E22k?((z
*/ *$W&jfW
publicint getEveryPage(){ |:&6eDlR
return everyPage; n\l?+)S *
} &v0-$
m;]wKd"
/** CpmT*
* @param everyPage %ACW"2#(
* The everyPage to set. m|B=
*/ *
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publicvoid setEveryPage(int everyPage){ ;_)~h$1%=
this.everyPage = everyPage; 3g;,
} +Gt9!x}#e
1QG q;6\
/** )/%5f{+}
* @return 26rg-?;V^
* Returns the hasNextPage. kuy?n-1g
*/ {]<c6*gQ
publicboolean getHasNextPage(){ \agZD+
return hasNextPage; T5."3i
} 1.F&gP)9
rBNVI;JZW
/** 8ROKfPj;z
* @param hasNextPage p8_^6wfg
* The hasNextPage to set. ]*\MIz{56'
*/ hj9TiH/+
publicvoid setHasNextPage(boolean hasNextPage){ Td|u@l4B
this.hasNextPage = hasNextPage; 14B',]`
} %7)TiT4V
3X`9&0:j%
/** v}6iI}r
* @return )x7n-|y6
* Returns the hasPrePage. 31a,i2Q4
*/ \X:e9~
publicboolean getHasPrePage(){ oT):#,s
return hasPrePage; M}x%'=Pox
} **Ioy+
hr
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>A
/** %S^hqC
* @param hasPrePage 05q760I+
* The hasPrePage to set. BsIF3sS#9
*/ [~s+,OO9)
publicvoid setHasPrePage(boolean hasPrePage){ QDg5B6>$
this.hasPrePage = hasPrePage; @@Ybg6.+*
} N3|:MMl
)}`z<)3jP
/** 6iyl8uL0J
* @return Returns the totalPage. #dWz,e3
* Lj<TzPzg*
*/ P_1WJ
publicint getTotalPage(){ M?eP1v:<+G
return totalPage; e$Ds2%SaT
} j8`
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"/aZ*mkjfJ
/** PN
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* @param totalPage 0\tac/
* The totalPage to set. AygdAg'\
*/ Ayw_LCUD
publicvoid setTotalPage(int totalPage){ ]`&_!T
this.totalPage = totalPage; bE
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} q !z"YpYB
G;G*!nlWf
} X3:z=X&Zd
1'E=R0`pA
$*#^C;7O
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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 NZB*;U~t
]!B0= XP
个PageUtil,负责对Page对象进行构造: !E 5FU *s
java代码: 4^L;]v,|7
T UcFx_
"/Qz?1>l+
/*Created on 2005-4-14*/ M%S7cIX
]F
package org.flyware.util.page; ?'MkaG0g
[gmov)\c
import org.apache.commons.logging.Log; "`49m7q1H
import org.apache.commons.logging.LogFactory; kw#X,hP
UA6id|G
/** o8g7wM]M
* @author Joa .dlsiBh
* +;KUL6
*/ 6dIPgie3w
publicclass PageUtil { OX7=g$S 1
hu}$ \
privatestaticfinal Log logger = LogFactory.getLog e"S?qpJK
P51M?3&=l
(PageUtil.class); R5uG.Oj-2
ccag8LC
/** %;'~TtW5
* Use the origin page to create a new page j&d5tgLB
* @param page , _e[P
* @param totalRecords M}\h?s
* @return P8z%*/
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*/ MbRTOH
publicstatic Page createPage(Page page, int oe*1jR_J`[
t eY@)F
totalRecords){ Ou_H&R
return createPage(page.getEveryPage(), q5(t2nNb
M&V'*.xz
page.getCurrentPage(), totalRecords); WywS1viD
} BPO5=]W 7
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/** h3?>jE=H
* the basic page utils not including exception fN&\8SPE
/+Z*)q+SbT
handler &u>dKf)5
* @param everyPage 3a?-UT!
* @param currentPage -l= 4{^pK
* @param totalRecords w|9 >4
* @return page "2cOS PpQL
*/ FH,]'
publicstatic Page createPage(int everyPage, int $tmdE)"&
7iP+!e}$.
currentPage, int totalRecords){ o}rG:rhIh
everyPage = getEveryPage(everyPage); cRT'?w`}
currentPage = getCurrentPage(currentPage); -5<[oBL;
int beginIndex = getBeginIndex(everyPage, |R}=HsYey
>w
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currentPage); k>($[;k|b
int totalPage = getTotalPage(everyPage, (P|[<Sd
G4cgY|71
totalRecords); i0=U6S:#
boolean hasNextPage = hasNextPage(currentPage, U~x]2{}
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totalPage); T*x2+(r
boolean hasPrePage = hasPrePage(currentPage); #Z%"
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|MwV4^
returnnew Page(hasPrePage, hasNextPage, I1<WHq
everyPage, totalPage, 6'# 5Dqw"r
currentPage, TjUwe@&Rw
.?:*0
beginIndex); ?M4o>T%p "
} #t
;`
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privatestaticint getEveryPage(int everyPage){ ;{ifLI0#
return everyPage == 0 ? 10 : everyPage; s)1-xA{'.
} =
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6("_}9ZOc
privatestaticint getCurrentPage(int currentPage){ xKUL}>8
return currentPage == 0 ? 1 : currentPage; 2%%\jlT_
} =]7o+L4
p!UR;xHI\
privatestaticint getBeginIndex(int everyPage, int ALMsF2H
o2!738
currentPage){ T9nb ~P[
return(currentPage - 1) * everyPage; ?
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} \,#$,dUXD
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privatestaticint getTotalPage(int everyPage, int 6w^P{%ul
( /]'e}
totalRecords){ ,X@o@W+L
int totalPage = 0; Uy?jVPL
j?K$w`
if(totalRecords % everyPage == 0) yK*vn]}
totalPage = totalRecords / everyPage; =CLPz8
else "hk#pQ
totalPage = totalRecords / everyPage + 1 ; e*:K79y
| v!N1+v0
return totalPage; QOWGQl%!
} d(q1?{zr4
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privatestaticboolean hasPrePage(int currentPage){ *[si!e%
return currentPage == 1 ? false : true; hYJzF.DW<$
} cN,*QN
}3#\vn0gT
privatestaticboolean hasNextPage(int currentPage, 4XpWDfa.}
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int totalPage){ 2k.VTGak
return currentPage == totalPage || totalPage == X*2W4udF
cH5i420;aO
0 ? false : true; f[o~d`z
} ',EI[
]+
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} $TIeeTB
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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。 y7HFmGM
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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 ~c)&9'
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做法如下: M$K%e
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 (`.# n3{
pD{OB
的信息,和一个结果集List: Q#g`D,:o%~
java代码: 8V:;HY#
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EFX2>&mWo8
/*Created on 2005-6-13*/ [q9B"@X
package com.adt.bo; 0*{(R#
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import java.util.List; OUBGbld
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import org.flyware.util.page.Page; {)" 3
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/** !Tnjha*
* @author Joa D$ds[if$U,
*/ 7H Har'=T
publicclass Result { o}AXp@cqi
!^arWH[od
private Page page; =$'>VPQ
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private List content; bn*:Bn1
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/** -`L`kL<
* The default constructor l(>6Yq
*/ a{8a[z
public Result(){ "| '~y}v_
super(); dseI~}
} ZLQmEF[>
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/** j<^!"_G]*?
* The constructor using fields 5%,3)H{;t
* r^
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* @param page _}R$h=YD
* @param content Z
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*/ I\)`,w
public Result(Page page, List content){ KXt8IMP_"y
this.page = page; %vmd2}dA
this.content = content; A?YYR%o%'
} 3BMz{ny=
p$Tk;;wm
/** j97+'AKX
* @return Returns the content. hUMG}<
*/ c9/w{}F
publicList getContent(){ JH?ohA
return content; Cv#aBH'N
} T~UDD3
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/** ";/]rwHa)
* @return Returns the page. }c,b]!:
*/ TEV DES
public Page getPage(){ #0AyC.\
return page; ?1=.scmgDG
} k{vj,#
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/** P'~`2W0sz
* @param content >iTmILA
* The content to set. Fs]N9],=I
*/ ?b_E\8'q]
public void setContent(List content){ xw*e`9vAe
this.content = content; ?_ H9>/:.
} OX"Na2-el
/d&m#%9Up]
/** x1:mT[[$
* @param page P-X|qVNK1Z
* The page to set. Bl\:YYd
*/ vQ<
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publicvoid setPage(Page page){ -ssb|r
this.page = page; 'o&d!
} S*l/
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} dDS{XR
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t w4,gW
2. 编写业务逻辑接口,并实现它(UserManager, _9BL7W $;
czRBuo+k+
UserManagerImpl) 9B~&d(Bm
java代码: \S h/<z
Tg)F.):
2|k$Vfz
/*Created on 2005-7-15*/ t jM9EP
package com.adt.service; {C w.?JU
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import net.sf.hibernate.HibernateException; q^[t</_N
e;6:U85LS
import org.flyware.util.page.Page; `}Y)l:G*g
AE~zmtW
import com.adt.bo.Result; )WvKRp r
CaYb}.:AX
/** e=LrgRy+
* @author Joa )?{<Tt@
*/ J`g5Qn@S
publicinterface UserManager { xOkdu k]
D5"5`w=C
public Result listUser(Page page)throws &[yC M!
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HibernateException; 8L[+$g`
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} Y%i<~"k
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b
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java代码: 1ZFKLI`V
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-aT-<+?s
/*Created on 2005-7-15*/ inW7t2p<s
package com.adt.service.impl; F
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]v<8l4p;
import java.util.List; hT%fM3|,e
8i;1JA
import net.sf.hibernate.HibernateException; &l cfX\y
vapC5,W"2-
import org.flyware.util.page.Page; C-edQWbcP
import org.flyware.util.page.PageUtil; |0ZJ[[2
M[I=N
import com.adt.bo.Result; o?ug`m"
import com.adt.dao.UserDAO; @.sn
import com.adt.exception.ObjectNotFoundException; 6zM:p/
import com.adt.service.UserManager; :[@rA;L
/J^dzvH
/** 23CvfP
* @author Joa !WXV1S
*/ ,OlS>>,
publicclass UserManagerImpl implements UserManager { |2'WSAWG
{
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private UserDAO userDAO; w!UF^~
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/** SB%D%Zx6'%
* @param userDAO The userDAO to set. POk5+^
*/ =.s0"[%
publicvoid setUserDAO(UserDAO userDAO){ pwMA,X/{
this.userDAO = userDAO; cPcH
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} i>S@C@~
[ as,AX
/* (non-Javadoc) lAnOO5@8
* @see com.adt.service.UserManager#listUser
~;?mD/0k
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(org.flyware.util.page.Page) uWx<J3~q.
*/ YXo?(T..
public Result listUser(Page page)throws +8<$vzB
L)M{S3q,
HibernateException, ObjectNotFoundException { 8}yrsF#
int totalRecords = userDAO.getUserCount(); 4evN^es'I_
if(totalRecords == 0) 2lfEJw($
throw new ObjectNotFoundException `Ku:%~$/
NtGJpT4YX
("userNotExist"); 8$c) ]Bv
page = PageUtil.createPage(page, totalRecords); wMkHx3XD
List users = userDAO.getUserByPage(page); _#M4zO7
returnnew Result(page, users); .S:(O+#Gm
} ,i6U*
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} @@@}FV&
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e
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ;8=Bee4
<LZ#A@]71
询,接下来编写UserDAO的代码: "~ =O`5V
3. UserDAO 和 UserDAOImpl: S?Cd,WxT
java代码: m>Z3p7!N}
O-.G("
)09ltr0@"
/*Created on 2005-7-15*/ ?h1g$SBxk
package com.adt.dao; w3i74C&0
h>>~B i
import java.util.List; - 5v{p
@u$NB3
import org.flyware.util.page.Page; R{[v#sF >#
"KF]s.
import net.sf.hibernate.HibernateException; !pj&