Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 oT7=
>:whNp
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?UC3ES
_pSCv:3T
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 =&QC&CqEi
~Qzb<^9]
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 gU7@}P
^goa$uxU
。 bWN%dn$$M
,EyZ2`|
分页支持类: EG<YxNX,
j rX.e
java代码: MP|J 0=H5
(9_~R^='y
cqzd9L6=
package com.javaeye.common.util; `6KTQk'
;b=3iT-2"
import java.util.List; 8}/v[8p
gA)!1V+:
publicclass PaginationSupport { _jV(Gv'
G.2ij%Zz
publicfinalstaticint PAGESIZE = 30; <}~`YU>=v
!`8WNY?K
privateint pageSize = PAGESIZE; #}50oWE
v:*t5M
>
privateList items; u<x2"0f
}cK<2J#
privateint totalCount; .\kcWeC\
2BLcun
privateint[] indexes = newint[0]; 7\sJ=*
D8a[zXWnc
privateint startIndex = 0; 5BvCP
DPuz'e*
public PaginationSupport(List items, int (VYY-%N`
zGrUl|j
totalCount){ / ,3,l^kZ
setPageSize(PAGESIZE); G=lcKtMdg
setTotalCount(totalCount); Hl"qLrb4
setItems(items); dmHpF\P5f
setStartIndex(0); |oq27*ix~m
} 4q"x|}a
^h+,Kn0@
public PaginationSupport(List items, int YqsN#E3pf
[h
"*>J{
totalCount, int startIndex){ d52l)8
setPageSize(PAGESIZE); VUXG%511T
setTotalCount(totalCount); uT8@p8
setItems(items); t^HQ=*c
setStartIndex(startIndex); lv_|ws
} K!/"&RjW.
)i&z!|/2
public PaginationSupport(List items, int +I$c+WfU
B4^+&B#
totalCount, int pageSize, int startIndex){ WvG0hts=[
setPageSize(pageSize); cE}R7,y
setTotalCount(totalCount); z?$F2+f&
setItems(items); {HKd="%VG
setStartIndex(startIndex); G}aw{Vbg_
} # Ny
WVc3C-h,
publicList getItems(){ "(y",!U@
return items; 3F' {JP
} zk8 o[4
ZV}"k_+-
publicvoid setItems(List items){ ^6!C":f
this.items = items;
laX(?{_
} NG-Wn+W@b
fY@Y$S`Fh
publicint getPageSize(){ `}:q@:%
return pageSize; cstSLXD
} ,1'9l)zP
}Z
T{
publicvoid setPageSize(int pageSize){ $:M *$r^u
this.pageSize = pageSize; Jy)E!{#x
} wD|,G!8E2
#L}YZ
publicint getTotalCount(){ uGm~ Oo
return totalCount; ^R* _Q,o#
} Bq~!_6fB
{UpHHH:X#
publicvoid setTotalCount(int totalCount){ -<kl d+
if(totalCount > 0){ 2Y_ `&
this.totalCount = totalCount; @xKLRw
int count = totalCount / !'>(r K$
4`lt 4L
pageSize; V{17iRflf
if(totalCount % pageSize > 0) 8<(qN>R
count++; 1PWs">*(
indexes = newint[count]; q[4{Xh
for(int i = 0; i < count; i++){ y+f@8]
indexes = pageSize * ( lbF/F>v
c"BFkw
i; OgJd^
} su]CaHU
}else{ ( zQ)EHRD
this.totalCount = 0; [:gPp)f,
} v3|-eWet^
} (Fq|hgOA>M
s(*LV2fa
publicint[] getIndexes(){ :5!>h8p;
return indexes; Jlw<%}r
} 9{{QdN8
DQ7+
publicvoid setIndexes(int[] indexes){ USz|Rh
this.indexes = indexes; ;xFx%^M}br
} {~.~ b+v
"&jA
CI
publicint getStartIndex(){ )%rGD
=2~
return startIndex; X|+ o4R?
} z@\C/wX
&$yC+cf
publicvoid setStartIndex(int startIndex){ n4Fh*d ixg
if(totalCount <= 0) 8A/;a{
this.startIndex = 0; Wyu$J
elseif(startIndex >= totalCount) R?"sM<3`e
this.startIndex = indexes P7GuFn/p~2
zbH Nj(~
[indexes.length - 1]; q)%F#g
elseif(startIndex < 0) "Y(stRa
this.startIndex = 0; yl|?+
else{ MhMY"bx8
this.startIndex = indexes )cA#2mlS'1
Jy&O4g/'5
[startIndex / pageSize]; [{.e1s<EK
} Q 6djfEN>
} OiI[w8
#<ppiu$
publicint getNextIndex(){ r|$@Wsb?#
int nextIndex = getStartIndex() + ~(E.$y7P
""cnZZ5)
pageSize; a12Q/K
if(nextIndex >= totalCount) m0xL'g6F
return getStartIndex(); 6*`KC)a
else 6&~8TH
return nextIndex; qEvHrsw},
} Rh!B4oB4
MfNxd
6w
publicint getPreviousIndex(){ V1Yab#
int previousIndex = getStartIndex() - :1h1+b@,
S~BBBD
pageSize; $OI 6^
if(previousIndex < 0) hdky:2^3
return0; nulCk33x'=
else t)|*-=
return previousIndex; wQR>S>p
} l ;"v&?
@<]sW*s
} 3IXai)6U
k
I{)"
I9S=VFhZ`
\Eq,4-q
抽象业务类 up+W[#+
java代码: v+a$Xh3Y~
u{#}Lo>B #
e>yPFXSk
/** Y~ j.Kt
* Created on 2005-7-12 (Fc\*Vn
*/ E'3=qTbiD
package com.javaeye.common.business; *v1M^grKd
2aQR#lcv
import java.io.Serializable; B|%(0j8
import java.util.List; ,(d\! T/]'
:
utY4
import org.hibernate.Criteria; Jg3OMUt
import org.hibernate.HibernateException; FT.6^)-
import org.hibernate.Session; }DH3_M!
import org.hibernate.criterion.DetachedCriteria; }^|g|xl!
import org.hibernate.criterion.Projections; uTsxSkHb/
import s"u6po.'
Z(Styn/x
org.springframework.orm.hibernate3.HibernateCallback; a?Q\nu1
import W+HiH`Qb]
)xJCH9h
org.springframework.orm.hibernate3.support.HibernateDaoS aYTVYg
^L}ICm_#
upport; "R8: s
Ul"9zTH
import com.javaeye.common.util.PaginationSupport; 50,`=Z
[ .]x y
public abstract class AbstractManager extends 5%H(AaG*q
!,D7L6N
HibernateDaoSupport { a%\6L
R8[l\Y>Ec
privateboolean cacheQueries = false; ?HD(EGdx
c6v@6jzx0Y
privateString queryCacheRegion; &(M][Uo{|'
tK@|sZ>3\
publicvoid setCacheQueries(boolean h"~i&T
h
NifD
pqjgt
cacheQueries){ jA<(#lm;
this.cacheQueries = cacheQueries; 3y&N}'R(F
} M%(B6};J
'p%aHK{
publicvoid setQueryCacheRegion(String m+66x {M2c
%:yp>nm
queryCacheRegion){ Eb
8vnB#
this.queryCacheRegion = s
&4k
<x&0a$I
queryCacheRegion; WBb@\|V|
} L7kNQ/
qp#Is{=m
publicvoid save(finalObject entity){ h%4aL38
getHibernateTemplate().save(entity); \!O3]k,r
} UA>3,|gV1
i}&&rr
publicvoid persist(finalObject entity){ P{T\zT
getHibernateTemplate().save(entity); }kJfTsFS
} n ~c<[
E[Xqyp!<
publicvoid update(finalObject entity){ 0.pZlv
getHibernateTemplate().update(entity); SB1j$6]OR7
} ;_$Q~X
m1pge4*
publicvoid delete(finalObject entity){ )FLDCer
getHibernateTemplate().delete(entity); PjwDth
A1
} r4YiXss
&Hz{
publicObject load(finalClass entity, |}^me7C,[
=g.R?H8cj5
finalSerializable id){ Ux[2 +Cf
return getHibernateTemplate().load KjWF;VN*[3
,=_)tX^
(entity, id); I |PEC-(
} vR"?XqgZ
$7bLw)7
publicObject get(finalClass entity, (-}:'5|Yj
GG0H3MSc
finalSerializable id){ 'iY~F 0U
return getHibernateTemplate().get _sp,,gz
;s*
(entity, id); ]|JQH
} IOfxx>=3
h.Y&_=Gc
publicList findAll(finalClass entity){ ddTsR
return getHibernateTemplate().find("from Q,ezAE
^`~s#L7
" + entity.getName()); k kZ2Jxvx
} UWW^g@d4
='W=
publicList findByNamedQuery(finalString y ;/T.W9!
MZ2/ks
namedQuery){ kC,=E9)O
return getHibernateTemplate
saRYd{%+
f 7R/i
().findByNamedQuery(namedQuery); r|MBkpcvp
} %fT%,(
w}t
-R]Iu\
publicList findByNamedQuery(finalString query, T\ *#9a
A
".v+
finalObject parameter){ #r|qitL3
return getHibernateTemplate IZ/PZ"n_(
FmtgH1u:=
().findByNamedQuery(query, parameter); I`~Giz7@
} {})d}dEC
]Cc3}+(s
publicList findByNamedQuery(finalString query, qix$ }(P
lGlh/B%
finalObject[] parameters){ 'iM#iA8
return getHibernateTemplate "L0Q"t:
8t;vZ&
().findByNamedQuery(query, parameters); _ez*dE%
} @Ojbu@A
FNN7[ku!
publicList find(finalString query){ YujR}=B!/
return getHibernateTemplate().find *M? [Gro/
~|lEi1|
(query); @3w6!Sgh
} -Qy@-s $
]x1;uE?1J
publicList find(finalString query, finalObject ;tJ}*!z
W
8|L U=p`y'
parameter){ !V'~<&
return getHibernateTemplate().find (+CNs
+F?}<P_v
(query, parameter); tP:ER
} bMA0#e2
9bQD"%ha=d
public PaginationSupport findPageByCriteria <e?1&5 6
4<j7F4
(final DetachedCriteria detachedCriteria){ *V`E)maU
return findPageByCriteria ;b5^)S
.GSK!1{@
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 8I}ATc
} "X(9.6$_
y$}o{VE{x
public PaginationSupport findPageByCriteria ~eyZH8&
/HE{8b7n3F
(final DetachedCriteria detachedCriteria, finalint N79?s)l:K
3Q#Tut
startIndex){ h+c9FN
return findPageByCriteria i*]$_\yl"
dEI]|i
r
(detachedCriteria, PaginationSupport.PAGESIZE, hcqg94R#_
cCx_tGR"
startIndex); {.j030Q
} J'E?Z0
cGSG}m@B`
public PaginationSupport findPageByCriteria o
zMn8@R
ri2`M\;gt
(final DetachedCriteria detachedCriteria, finalint +gyGA/5:d$
M9QYYo@
pageSize, to{7B7t>q
finalint startIndex){ >g;995tG
return(PaginationSupport) + MtxS l
@iU(4eX
getHibernateTemplate().execute(new HibernateCallback(){ Qp;FVUw9
publicObject doInHibernate ;0 4< 9i
arc{:u.K
(Session session)throws HibernateException { =D`:2k~
,
Criteria criteria = U+Vb#U7;
>|pN4FS
detachedCriteria.getExecutableCriteria(session); cX#U_U~d
int totalCount = #Ibpf ,
Gn %"B6
((Integer) criteria.setProjection(Projections.rowCount (]nX:t
$!vK#8-&{
()).uniqueResult()).intValue(); z?Cez*.h>
criteria.setProjection ;LC?3.
T<%%f.x[s
(null); )&$mFwf
List items = aM4-quaG]
[;Jq=G8&t
criteria.setFirstResult(startIndex).setMaxResults z?t75#u9.
4iv&!hAc;
(pageSize).list(); zGwM# -
PaginationSupport ps = #l
6QE=:
[ <j4w
new PaginationSupport(items, totalCount, pageSize, wzF%R{;
[NK&s:wMk
startIndex); 0}"'A[xE
return ps; Db*&'32W
} } 4ZWAzH
}, true); qi['~((
} \b}%A&Ij
y
q!{\@-
public List findAllByCriteria(final <
w;490g
P}"T3u\N
DetachedCriteria detachedCriteria){ h2y<vO
return(List) getHibernateTemplate FY)US>
X4JSI%E
().execute(new HibernateCallback(){ s~m]>^?8MR
publicObject doInHibernate '?$R YU,
C;%1XFzM
(Session session)throws HibernateException { T930tX6"h
Criteria criteria = %R<xe.X
A`* l+M^z
detachedCriteria.getExecutableCriteria(session); bZ#5\L2
return criteria.list(); 6MpV,2:>
} G0h e'BR
}, true); ^vJy<
} A: O"N
@V Sr'?7-
public int getCountByCriteria(final :_h#A}8Xd
Ek60[a
DetachedCriteria detachedCriteria){ VV/aec8
Integer count = (Integer) "H]R\xp
mRy0zN>?
getHibernateTemplate().execute(new HibernateCallback(){
D,()e^o
publicObject doInHibernate {mB!mbr
}S;A%gYm
(Session session)throws HibernateException { M }$Td_g
Criteria criteria = =&)R2pLs*
T@Z-;^aV
detachedCriteria.getExecutableCriteria(session); RWFvf
return PU4-}!K
LKA/s ~G
criteria.setProjection(Projections.rowCount *=P*b|P"$
('2Z&5
()).uniqueResult(); y@r0"cvz9
} J$d']%Dwb
}, true); !AG {`[b
return count.intValue(); $$XeCPs0
} "8Lv
} rN,T}M=2
=y=MljEX
&(m01
Hp*N%
5n[''#D
<O.|pJus
用户在web层构造查询条件detachedCriteria,和可选的 +$F,!rV-s
%a]Imsm
startIndex,调用业务bean的相应findByCriteria方法,返回一个 >qPP_^]
j^/=.cD|
PaginationSupport的实例ps。 $EL:Jx2<
!;Ke# E_d
ps.getItems()得到已分页好的结果集 wG73GD38
ps.getIndexes()得到分页索引的数组 agq4Zy
ps.getTotalCount()得到总结果数 {B4.G8%Z
ps.getStartIndex()当前分页索引 ^v+p@k
ps.getNextIndex()下一页索引 czsnPmNEI
ps.getPreviousIndex()上一页索引 r5y*SoD!
xUTTRJ(\
5}b)W>3@`
dK4w$~j{k
g@ .e%
99"8d^{z
G E? \Vm
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 y#= j{
F,V|In
,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 z6P~HF+&h
q7I!wD9Cff
一下代码重构了。 n(i/jW~0w
rM?
J40&.
我把原本我的做法也提供出来供大家讨论吧: M@Ti$=
UY .-Qt
首先,为了实现分页查询,我封装了一个Page类: p=\Q7<Z6d,
java代码:
qt6@]Y
[NV/*>"j&
j<R&?*
/*Created on 2005-4-14*/ >WLHw!I!6
package org.flyware.util.page; nFWiS~(#sW
V9D q<y-y
/** 2qQ;U?:q
* @author Joa "y5bODq3t
* x[u6_6=q9
*/ qj4jM7
publicclass Page { w"W;PdH)
x&r f]R
/** imply if the page has previous page */ lPrAx0m13%
privateboolean hasPrePage; qlnA7cK!
y(#6nG@S
/** imply if the page has next page */ @(0O9L
F
privateboolean hasNextPage; aMVq%{U
ZUvc|5]
/** the number of every page */ Q3Y(K\
privateint everyPage; p 16+(m
c?KIHZ0
/** the total page number */ #<s"?Y%-
privateint totalPage; @}Q!K*
UFC^lv
/** the number of current page */ 'ka$@,s :
privateint currentPage; 9Q*:II
}0f~hL24
/** the begin index of the records by the current KUpj.[5qo
g9=_^^Tg
query */ \}X[0ct2!
privateint beginIndex; >
6=3y4tP
^8YBW<9
|>1#)cONW
/** The default constructor */ Cs\jPh;"
public Page(){ &C)97E
gGN6Yqj0
} LDYa{w-t
\cf'Hj}
/** construct the page by everyPage 4eF{Y^
* @param everyPage +zXcTT[V
* */ IVa6?f6H_
public Page(int everyPage){ ;]bW
this.everyPage = everyPage; '&2-{Y [!
} 27}7
n
<_]W1V:0
/** The whole constructor */ .$
YYN/+W
public Page(boolean hasPrePage, boolean hasNextPage, 6{0MprY
REh\WgV!u
URt+MTU[
int everyPage, int totalPage, VF b
int currentPage, int beginIndex){ )eqF21\
this.hasPrePage = hasPrePage; 6urU[t1
this.hasNextPage = hasNextPage; 6'.)z,ts
this.everyPage = everyPage; E25w^x2
this.totalPage = totalPage; *xITMi
this.currentPage = currentPage; Xbrc_V\_
this.beginIndex = beginIndex; WJ LqH<
} }%<_>b\
9XhH*tBn7(
/** M%RH4%NZ0
* @return &pR 8sySu
* Returns the beginIndex. TAqX
f_
*/ Z[B:6\oQ
publicint getBeginIndex(){ E|jU8qz>P
return beginIndex; l2YA/9.
} ,?HM5c{'[Y
) jt?X}
/** 0c8_&
* @param beginIndex * dk(<g=fM
* The beginIndex to set. wAJ=rRI
*/ )]4=anJu@|
publicvoid setBeginIndex(int beginIndex){ u^#e7u
this.beginIndex = beginIndex; ZHlHnUo
} ~B?Wg!
2$`Y 4b 3t
/** zL3zvOhu}
* @return K4+|K:e
* Returns the currentPage. 71ab&V il
*/ b'z\|jY
publicint getCurrentPage(){ XHOS"o$y
return currentPage; l N0u1)'2
} 8R-;cBT
5uOz #hN
/** mdo$d-d&
* @param currentPage 4sW~7:vU
* The currentPage to set. 4tx6h<L#s
*/ }B!io-}
publicvoid setCurrentPage(int currentPage){ m(^N8k1K;
this.currentPage = currentPage; Plhakngj
} @K}h4Yok
^zS;/%
/** Bu+?N%CBi
* @return L6;'V5Mg72
* Returns the everyPage. LGVy4D
*/ wZW\r!Us
publicint getEveryPage(){ F?0Q AA
return everyPage; ckv8QAm
} [tElt4uG
^]~!:Ej0
/** B#35)QI
* @param everyPage $$< I}eMd>
* The everyPage to set. ):}A Quy]
*/ !_;J@B
publicvoid setEveryPage(int everyPage){ DL,]iJm
this.everyPage = everyPage; TIR Is1
} (<-m|H};
8G9( )UF.
/** %+<1X?;,Fq
* @return #};Zgixo$
* Returns the hasNextPage. };EB[n
*/ jW-;Y/S
publicboolean getHasNextPage(){ 412E7
return hasNextPage; hE$3l+
} |JP'j1 Ka
e@ $|xa")
/** t}?-ao
* @param hasNextPage bR~5
:A^
* The hasNextPage to set. o;#8=q
*/ 3K/'K[~
publicvoid setHasNextPage(boolean hasNextPage){ ,"{e$|iY
this.hasNextPage = hasNextPage; V<;_wO^
} 0IA'5)
L/I ]
NA!U
/** DlAwB1Ak
* @return KaHe(
* Returns the hasPrePage. q^n
LC6q
*/ ;Ru[^p.{
publicboolean getHasPrePage(){ Q&_#R(3j;
return hasPrePage; >l/pwb@
} 6A}tA$*s7
JnIG;/
/** inZ0iU9dy
* @param hasPrePage 5,V*aP
* The hasPrePage to set. "r3h+(5
*/ 3bjCa\ "
publicvoid setHasPrePage(boolean hasPrePage){
2Vu?Y
this.hasPrePage = hasPrePage; 9
`q(_\ x
} RrYNtc
<F"G~.^ *s
/** ?4Fev_5m
* @return Returns the totalPage. 5p5"3m;M7
* apgKC;
*/ -1`}|t;
publicint getTotalPage(){ _#+l?\u
return totalPage; 1uR@ZK
} 3d7A/7S
TXS`ey
/** 3>73s}3
* @param totalPage L~by `q N_
* The totalPage to set. jG)66E*"
*/ Y9vVi]4
publicvoid setTotalPage(int totalPage){ *yo'Nqu
this.totalPage = totalPage; -yg;,nCg
} yOvV"x]
DIWyv-
} ,j\uvi(Y
v0tFU!Q%
dLwP7#r
5 wN)N~JE
jsr)
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 :`"-Jf
6Yt3Oq<U
个PageUtil,负责对Page对象进行构造: NLYf
java代码: x2aG5@<3
-f1}N|hy
;X0uA?
/*Created on 2005-4-14*/ 8x7TK2r
package org.flyware.util.page; [;F!\B-
<S6?L[_
import org.apache.commons.logging.Log; hNgT/y8
import org.apache.commons.logging.LogFactory; !W0JT#0
7.g,&s%q
/** \u[5O@v#
* @author Joa !8W0XUqh+
* M(C}2.20
*/ :eB+t`M
publicclass PageUtil { AeN:wOm
{_$['D^ az
privatestaticfinal Log logger = LogFactory.getLog yfR0vp<&
KM"?l<x0Y
(PageUtil.class); *ezft&{)`
{)!ua7GF0H
/** 9L4;#cy
* Use the origin page to create a new page {.o4U0+
* @param page I3T;|;P7
* @param totalRecords DW :\6k
* @return ]~f-8!$$R
*/ TeR bW
publicstatic Page createPage(Page page, int !bnnUCTb\
H!6&'=c {k
totalRecords){ tI#65ox#
return createPage(page.getEveryPage(), 2bw.mp&v1
;'Z"CbS+
page.getCurrentPage(), totalRecords); -4F}I3I
} j>
dZ26 >N
yT7{,Z7t
/** BePb8
k<y
* the basic page utils not including exception ?@`5^7*
$*P+
handler XbFo#Pwk
* @param everyPage @ptrF
pSL
* @param currentPage [O!/hppN
* @param totalRecords ?6x&A t
* @return page yGC
HWP
*/ iS"6)#a72
publicstatic Page createPage(int everyPage, int -y?ve od#
)-}<}< oO
currentPage, int totalRecords){ !O'p{dj][
everyPage = getEveryPage(everyPage); 6Rq +=X
currentPage = getCurrentPage(currentPage); e},:QL0X
int beginIndex = getBeginIndex(everyPage, xt`a":lr u
HL>l.IG?
currentPage); EUH9R8)
int totalPage = getTotalPage(everyPage, w Bm4~~_
p}wysVB
totalRecords); X(DP=C}v9
boolean hasNextPage = hasNextPage(currentPage, "@5{=
`Jj b4]
totalPage); v{*2F
boolean hasPrePage = hasPrePage(currentPage); mY XL
)
R\";{`M
returnnew Page(hasPrePage, hasNextPage, r8czDc),b
everyPage, totalPage, ybv< 1
currentPage, n%~r^C_
$ >].;y?$
beginIndex); QAZs1;lU
} gQY`qz
_ |HA\!
privatestaticint getEveryPage(int everyPage){ $`0,N_C<}
return everyPage == 0 ? 10 : everyPage; M;KeY[u
} u3UN
=_Z.x&fi
privatestaticint getCurrentPage(int currentPage){ @j%@Z
return currentPage == 0 ? 1 : currentPage; q1r-xsjV=
} 9fM=5
P$^I\aGO
privatestaticint getBeginIndex(int everyPage, int `(O#$n
$,I@c"m{
currentPage){ JEZ0O&_R
return(currentPage - 1) * everyPage; n>SK2`
} $!z .[GL
P(C5@x(Z
privatestaticint getTotalPage(int everyPage, int Tpkt'|8
G#uB%:)&0u
totalRecords){ jC?l :m?
int totalPage = 0; 0 EA3>$;
v"Ryg]^_
if(totalRecords % everyPage == 0) \]\GDpu[
totalPage = totalRecords / everyPage; la$%%@0/
else Bw[IW[(~!
totalPage = totalRecords / everyPage + 1 ; 7W&XcF
)RWukr+
return totalPage; UKB/>:R
} +9<:z\B|
X"HVK+
privatestaticboolean hasPrePage(int currentPage){ />>KCmc
return currentPage == 1 ? false : true; RcO.1@2
} [?2?7>D8
u'Hh||La"
privatestaticboolean hasNextPage(int currentPage, X~\O]
W}(T5D" 3x
int totalPage){ j4=\MK
return currentPage == totalPage || totalPage == ;LKYA?=/V
x&EMg!
0 ? false : true; rO/Sj<0^
} b!"FM/%
!)}z{,Jx
X]GodqL\
} 6W;`}'ap
1h)K3cC
Hbu
:HFJ!
;oVOq$ql
n
\&H~0X
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。 /WX&UAG
Ru);wzky
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 @bnw$U`+
&{q'$oF
做法如下: }XCh>LvX
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#1o
/Vx
EqIK
的信息,和一个结果集List: AB<bW3qf(
java代码: \3F)M`g
bIV9cpW
Mdu\ci)lr
/*Created on 2005-6-13*/ ,.<c|5R
package com.adt.bo; BcQw-<veu
X %7l!
k[
import java.util.List; RYl\Q,#
4 .(5m\s!
import org.flyware.util.page.Page; aH,NS
%[ o($a$
/** '#QZhz(+
* @author Joa !y2yS/
*/ #TeAw<2U
publicclass Result { <v\x<ul6
rQPO+
private Page page; t+0/$
'68#7Hs.
private List content; B.gEV*@
CT<z1)#@^
/** "
#U-*Z7
* The default constructor 'P%&*%
*/ wx2 z 9Q
public Result(){ QG@Z%P~,E
super(); lJS3*x#H
} QlH[_Pi
C]na4yE8
/** H87k1^}HV
* The constructor using fields !D/W6Ic@
* 9'ky2
]w
* @param page cf%2A1I2W
* @param content zYftgH_o
*/ ;H?tcb*
public Result(Page page, List content){ WO^]bR
this.page = page; v sYbR3O
this.content = content; _m%Ab3iT~
} 9.6ni1a'
)2:U]d%pk
/** 6/Z_r0^O
* @return Returns the content. @%^h|g8>Fu
*/ W&&C[@Jd3
publicList getContent(){ 1{qG?1<zZ6
return content; }L^PZS@Jf
} aHNn!9#1
E*+]Iq1u
/** v,iq,p)&
* @return Returns the page. o$}$Z&LK
*/ `2q]ju
public Page getPage(){ b~TTz`HZ
return page; A[:(#iR5-E
} ]l
SUsdX[byb
/** _0Y?(}
* @param content #aKUD
* The content to set. S*WLb/R2
*/ x3nUKQtk:8
public void setContent(List content){ nKjT&R
this.content = content; wiM4,
} SJsbuLxR
+9#qNkP
/** "`*
>co6r
* @param page %e+*&Z',
* The page to set. F$O$Y[
*/ U.N&~S
publicvoid setPage(Page page){ Xl>ZnI];
this.page = page; -L
wz
T
} w@a|_?
} ')(U<5y)
acj-*I
VpED9l]y
[-R[rF
`SS[[FT$>
2. 编写业务逻辑接口,并实现它(UserManager, >U]KPL[%
TA~ZN^xI
UserManagerImpl) k#8E9/t@
java代码: ++=jh6
Rq|]KAN
y%<CkgZS
/*Created on 2005-7-15*/ n6C!5zq7U
package com.adt.service; }8`>n4
*mW 2vJ/B
import net.sf.hibernate.HibernateException; /!*=*
0sF|Y%N
import org.flyware.util.page.Page; Qzv&
zbvV:9N
import com.adt.bo.Result; -Q%Pg<Q-#
SES-a Mi3
/** Na+h+wD.D
* @author Joa !y$+RA7\
*/ VaO[SW^
publicinterface UserManager { !;Pp)SRzKG
JX#0<U|L
public Result listUser(Page page)throws .(yJ+NU
nB4+*=$E+-
HibernateException; .k|\xR
FRayB VHL
} cV4Y=
&
wv Mp~
+HG*T[%/
P4 #j;k4P
3L{)Y`P
java代码: ENFM``dV#
2{B
ScI5K
iMQ0Sq-%1
/*Created on 2005-7-15*/ (N`GvB7;
package com.adt.service.impl; }R_Rw:W
d\r-)VWSr"
import java.util.List; @eq.&{&
&+yoPF
import net.sf.hibernate.HibernateException; Uyd' uC
pB7^l|\]
import org.flyware.util.page.Page; 4Ofkagg
import org.flyware.util.page.PageUtil; A-YW!BT4
xRqA^Ad
import com.adt.bo.Result; MXDUKh7v3
import com.adt.dao.UserDAO; Ms-)S7tMz
import com.adt.exception.ObjectNotFoundException; "ZFH_5<
import com.adt.service.UserManager; #WAX&<m
6r`Xi&
/** 4I*'(6
,!
* @author Joa 1had8K-
*/ fm
q(!
publicclass UserManagerImpl implements UserManager { NB-%Tp*d
8fPTxvXqL
private UserDAO userDAO; >oC{YYcK
`O0y8
/** d;{k,rP6
* @param userDAO The userDAO to set. O9AFQ)u
*/ Ep3I*bQ
Y
publicvoid setUserDAO(UserDAO userDAO){ aS~~*UHW
this.userDAO = userDAO; [*@
+
} eDvh3Y<D
`oM'H+
/* (non-Javadoc) "+Sq}WR
* @see com.adt.service.UserManager#listUser _z9~\N/@[
J5Ti@(G5V
(org.flyware.util.page.Page) FOjX,@x&
*/ n+nZ;GJ5d
public Result listUser(Page page)throws (B!DBnq
<-,y0Y'
HibernateException, ObjectNotFoundException { '~1Zr uO
int totalRecords = userDAO.getUserCount(); nC)"% Sa
if(totalRecords == 0) F@zTz54t
throw new ObjectNotFoundException Oz)/KZ
lr@w1*
("userNotExist"); VCvf'$4(X
page = PageUtil.createPage(page, totalRecords); VmRfnH"
List users = userDAO.getUserByPage(page); oe!4ng[
returnnew Result(page, users); YGRb|P-
} q$Ms7` a
0f_A"K
} kO$n0y5e
k$pND,Ws
Tr;.O?@{t}
wc&D[M]-/
O2"V'(
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ln8es{q
%,zHS?)l
询,接下来编写UserDAO的代码: r|i)
3. UserDAO 和 UserDAOImpl: KL$> j/qT
java代码: W>:MK-_J
NQqNBI?cr
N>1d]DrQR
/*Created on 2005-7-15*/ ef/43+F^x
package com.adt.dao; >Psq" Xj
a2/Mf
import java.util.List; fzvyR2 I
Z'Pe%}3
import org.flyware.util.page.Page; #rNc+
UT[{NltH
import net.sf.hibernate.HibernateException; (]PH2<3t
;'
H\s
/** [JV?Mdzu
* @author Joa S\!vDtD@
*/ s!>9od6^
publicinterface UserDAO extends BaseDAO { W=OryEV?
+;M 5Sp
publicList getUserByName(String name)throws 0)ZLdF_6
m9+?>/R
HibernateException; sf:IA%.4t
emB<{kOkw
publicint getUserCount()throws HibernateException; o2q-x2uB
p(K^Zc
publicList getUserByPage(Page page)throws Hi*|f!,H?
B]Ec
HibernateException; #^R@EZ
M^>l>?#rl
} lcgG5/82
L4bYVTm|
yrl7
PsD)]V9%:
0rm(i*Q
java代码: o[i*i<jv-
dDD5OnWmJ
Mc!LC
.8
/*Created on 2005-7-15*/ (U_HX2f
package com.adt.dao.impl; yK$aVK"
b#R$P]dr=
import java.util.List; 1LAd5X
xtKU;+#
import org.flyware.util.page.Page; ?/-WH?1I
KWAd~8,mk
import net.sf.hibernate.HibernateException; oe0YxSauL
import net.sf.hibernate.Query; Q]3]Z/i
=1'WZp}D5
import com.adt.dao.UserDAO; o=K9\ l
,np|KoG|M
/** 5FF28C)>/
* @author Joa V>GJO (9
*/ w{So(AF
public class UserDAOImpl extends BaseDAOHibernateImpl Q1rEUbvCE
NL;sn"
implements UserDAO { `H$=hr
[Q J
/* (non-Javadoc) zufsmY4P
* @see com.adt.dao.UserDAO#getUserByName h.KgHMV`
lNtxM"G&
(java.lang.String) 1i_%1Oip
*/ 3la `S$c
publicList getUserByName(String name)throws a|.IAxJ
Q"GM3?
HibernateException { F`2h,i-9
String querySentence = "FROM user in class j+{cc: h"X
7YK6e
com.adt.po.User WHERE user.name=:name"; xXa4t4gR
Query query = getSession().createQuery "*N#-=MJF
SJc~E$5<
(querySentence); !H{>c@i
query.setParameter("name", name); mH4u@aQ}
return query.list(); Oh>hyY)}
} @)vQ>R\k<
"@/pQoLy
/* (non-Javadoc) `~"'\Hw
* @see com.adt.dao.UserDAO#getUserCount() :@ VC Kq!
*/ w-xigm>{Z
publicint getUserCount()throws HibernateException { >goHQ30:
int count = 0; 5??}9
String querySentence = "SELECT count(*) FROM ysl#Rwt/2
s S#/JLDx]
user in class com.adt.po.User"; D
.LR-Z
Query query = getSession().createQuery /!A"[Tyt
4[MTEBx
(querySentence); b-#lKWso
count = ((Integer)query.iterate().next D6+3f#k6
"5O>egt
()).intValue(); CR%h$+dzy
return count; v+`'%E
} R5(([C1
}4H}*P> +
/* (non-Javadoc) (v|<"
tv
* @see com.adt.dao.UserDAO#getUserByPage \_6
75R#gQ]EV
(org.flyware.util.page.Page) !MOsP<2
*/ zUZET'Bm9
publicList getUserByPage(Page page)throws Xw<;)m
&=$f\O1Ty
HibernateException { Dj'?12Onu=
String querySentence = "FROM user in class A9u>bWIE7
SK^(7Ws~0
com.adt.po.User"; R8eBIJ/@_
Query query = getSession().createQuery Dq$1
j%4Y
~gGkw#
(querySentence); g,M-[o=Fk
query.setFirstResult(page.getBeginIndex()) d;wq@e
.setMaxResults(page.getEveryPage()); js"5{w&
return query.list(); )oz2V9X{
} b=pk;'-
J:>o\%sF
} |YyNqwP`,
J'7;+.s(
GEh( pJ
VKX|0~
x=Oy 6"
至此,一个完整的分页程序完成。前台的只需要调用 Ak('4j!*}^
L?N-uocT
userManager.listUser(page)即可得到一个Page对象和结果集对象 NCG;`B`i
92A9gY
的综合体,而传入的参数page对象则可以由前台传入,如果用 X;GU#8W
4;CI<&S
webwork,甚至可以直接在配置文件中指定。 SJMbYjn0J
3W_7xLA
下面给出一个webwork调用示例: cSV&p|
java代码: uL1lB@G@
K<`Z@f3'w
zNoFM/1Vb
/*Created on 2005-6-17*/ $qdynKK
package com.adt.action.user; *?HoN;^
HF_8661g
import java.util.List; ss-6b^
eA-oqolY
import org.apache.commons.logging.Log; nK?S2/o#A
import org.apache.commons.logging.LogFactory; C~@m6K
import org.flyware.util.page.Page; &Mudu/KTr
H)gc"aRe;Y
import com.adt.bo.Result; E?P>s T3B
import com.adt.service.UserService; 5V =mj+X?
import com.opensymphony.xwork.Action; r~f;g9I
V@-Q&K#
/** Hv^Bw{"/R
* @author Joa 2zh-ms
*/ tp7$t#
publicclass ListUser implementsAction{ 0:u:#))1
Bl8|`R^g
privatestaticfinal Log logger = LogFactory.getLog &?H$-r1/?V
7Vh
(ListUser.class); w)@Wug
S\:+5}
private UserService userService; 1 Ga3[g
R5^6Kwu
private Page page; E&y)`>Nq{
Xy=ETV%
privateList users; >A-{/"p#
un-%p#
/* H{=G\N{
* (non-Javadoc) d<Q%h?E
* "B
(?|r%
* @see com.opensymphony.xwork.Action#execute() 3.BUWMD
*/ 7]T(=gg /
publicString execute()throwsException{ ")i)vXF'
Result result = userService.listUser(page); IjRUr \ l
page = result.getPage(); WH1" HO
users = result.getContent(); C5I7\9F)
return SUCCESS; iO?^y(phC
} C12V_)~2
|/n7(!7$[v
/** ^tG,H@95
* @return Returns the page. ly[dV.<P
*/ O$m &!J
public Page getPage(){ ?yq=c
return page; .9B@w+=6
} eQ#i.%
8&"Jlz
|
/** xlwf @XW
* @return Returns the users. T:{r*zLSN
*/ [(#)9/3,
publicList getUsers(){ # M/n\em"X
return users; Wd)\r.pJ
} $Uy+]9
^?""'1iuQx
/** U{oM*[
* @param page X5J )1rL
* The page to set. Tf]ou5|
*/ a7ZufB/
publicvoid setPage(Page page){ sZ&|omN
this.page = page; S8/~'<out
} k@|px#kq
SQ[D2v
/** bRm;d_9zC
* @param users lD[@D9
* The users to set. @U5gxK*
*/ 9]IZ3
fQX
publicvoid setUsers(List users){ z!bT^_Cc0
this.users = users; hwXsfh |
} dB4ifeT]
-A
w]b} #v
/** 7JQ4*RM
* @param userService +)q ,4+K%}
* The userService to set. @#,/6s7?
*/ FD
8Lk
publicvoid setUserService(UserService userService){ g&2g>]
this.userService = userService; L k
nK
} #9]2Uixq[
} t}h(j|
*aCVkFp
L$OZ]
MW rhVn{R
kGAgXtE
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, -%fj-Y7y
]ASw%Lw)
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 zMP6hn
W1"NKg~4
么只需要: ff.k1%wr^
java代码: HLV8_~gQPf
U3:|!CC)T
F=e;[uK\
<?xml version="1.0"?> +yfUB8Xw
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork UG`~RO
Y(7&3+'K
1.0//EN" "http://www.opensymphony.com/xwork/xwork- >KrI}>!9r
IW<rmP=R&
1.0.dtd"> &M?b08
EEZ~Bs}d
<xwork> lF/
Xs
"]]LQb$
<package name="user" extends="webwork- w@,p`
?B ,<gen
interceptors"> #!O)-dyF
@B>D>B
<!-- The default interceptor stack name 7_s+7x =
B(s^(__]
--> 8TB|Y
<default-interceptor-ref m"Mj3Z:
r4iNX+h?V
name="myDefaultWebStack"/> V||b%Cb1g
(VMCVZ
<action name="listUser" Q<V1`e
XTF[4#WO
class="com.adt.action.user.ListUser"> RA<ky*^dr
<param WIi,`/K+
VZcW
3/Y
name="page.everyPage">10</param> >fP;H}S6
<result +?"F=.SZ
KQ]sUNH
name="success">/user/user_list.jsp</result> AH'c:w]~
</action> !zOj`lx
fWEQ vQ
</package> M("sekL
w#A\(z%;x
</xwork> i,;eW&
z-gMk@l
Z9M$*Zp
)Hin{~h
rMIX{K)'f
[UzacX t
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 B6IKD
%p)&mYK{
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。 -(
p%+`
gkxHfm
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 *l
=f=
\f4rA?+f
(kY0<
S"G(_%
uQ_C<ii"W
我写的一个用于分页的类,用了泛型了,hoho s&VsK#
7/hn%obC
java代码: n^{h@u
n5"oXpcIx
J7",fb
package com.intokr.util; Yu" Q
$k&v
juB.
import java.util.List; VV1sadS:S`
&D{!zF
/** ZlC+DXg#S
* 用于分页的类<br> Hm'fK$y(
* 可以用于传递查询的结果也可以用于传送查询的参数<br> b3>zdS]Q
* ] \|2=
* @version 0.01 iupkb
* @author cheng MQw}R7
*/ ]3,9."^
public class Paginator<E> { {~9HJDcM
privateint count = 0; // 总记录数 e{87n>+,
privateint p = 1; // 页编号 n;:.UGl9.
privateint num = 20; // 每页的记录数 .+XK>jl+
privateList<E> results = null; // 结果 r@r*|50
^(+q1O'
/** cOdRb=?9
* 结果总数 b1#C,UWK
*/ ~xY"P)(x;
publicint getCount(){ GO2q"a
return count; Pi5MFw'v
} !\{2s!l~
r3' DXP
publicvoid setCount(int count){ ?F]P=S:x
this.count = count; Xux[
} |(Wwh$
*V:U\G
/** XZ.D<T"
* 本结果所在的页码,从1开始 iP9]b&
* XYP
RMa?
* @return Returns the pageNo. q
j21#q
.
*/ Peph..8 Z
publicint getP(){ y>t:flD*
return p; &uE )Vr4 R
} N`IXSE
WG A&Lr
/** 46)[F0,$r
* if(p<=0) p=1 C TG^lms
* V2?{ebx`
* @param p yc]_ ?S>9
*/ "4WnDd5"
publicvoid setP(int p){ +pT;;
9
if(p <= 0) Jxe 5y3*
(
p = 1; #y#TEw,
this.p = p; X1P1
$RdkR
} 4.,|vtp
^kcuRJ0*$
/** [g@qZ5I.
* 每页记录数量 m[y~-n
*/ S_Nm?;P
publicint getNum(){ SbX^DAlB1
return num; 'q;MhnU+
} feB ?
3C!|!N1Hn
/** mIG>`7`7N
* if(num<1) num=1 um$U3'0e
*/ <Tgubv+J
publicvoid setNum(int num){ N9d^;6;i
if(num < 1) [-l>fP0
num = 1; 8g{Mv#b%
this.num = num; Ygg+=@].@
} ;8vB7|54.
S"Vr+x?
/** UGM:'xa<T
* 获得总页数 j8e=],sQ
*/ &/^p:I
publicint getPageNum(){ sV5k@1Y
return(count - 1) / num + 1; [V?HK_~
} lrHN6:x(Y4
GNmP_N
/** EmUt/]
* 获得本页的开始编号,为 (p-1)*num+1 ]g9SUFM
*/ .yUD\ZGJu
publicint getStart(){ R6 ej
return(p - 1) * num + 1; Kk=>"?&
} V]Ccj\Oi
>#r0k|3J^J
/** {-7ovH?
* @return Returns the results. `R
(N3
*/ w_`;Mn%p
publicList<E> getResults(){ R=Lkf
return results; |QbCFihn
}
l8+1{6xP
.
&}x[~g
public void setResults(List<E> results){ J:uFQWxZ
this.results = results; D6e?J.
} 0[
"CP:u
hA/Es?U]
public String toString(){ +7WpJ;C4
StringBuilder buff = new StringBuilder p[WlcbBwT
ZI$P Qz2i
(); X0ugnQ6
buff.append("{"); S]fkA6v
buff.append("count:").append(count); }3Ke
buff.append(",p:").append(p); ~IO'"h'w
buff.append(",nump:").append(num); U%1M?vT/
buff.append(",results:").append $ta"Ug.z
!Y UT*
(results); b?Q$UMAbH
buff.append("}"); w(+L&IBC
return buff.toString(); ?en-_'}~a
} fOSJdX0e|Q
:G9d,B7*
} dwvc;f-
vfc5M6Vm)<
H
9/m6F