Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 67TwPvh
Si,6o!0k
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 {*KEP
?upM>69{
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 H]!"Zq k
598i^z{~0%
自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 51u0]Qx;fm
Bt#N4m[X*|
。 ^{{ qV
\9d$@V
分页支持类: yVc(`,tZ(
"KlwA.7/
java代码: *VeRVaBl
]k(]qZ
d3Rw!slIq
package com.javaeye.common.util; % nIf)/2g
AS,%RN^.
import java.util.List; ;=@0'xPEa-
&zs$x?/
publicclass PaginationSupport { iLz@5Zj8
23?rEhKe
publicfinalstaticint PAGESIZE = 30; eQ"E
h~26WLf.
privateint pageSize = PAGESIZE; N7_"H>O$0U
S$3JMFA
privateList items; :KN-F86i
6RM/GM
privateint totalCount; f5k6`7Vj]
$N\Ja*g
privateint[] indexes = newint[0]; kLY^!
ca}2TT&t
privateint startIndex = 0; -+5>|N#
Tr|JYLwF
public PaginationSupport(List items, int FqifriLN
,47qw0=C
totalCount){ &R siVBA
setPageSize(PAGESIZE); q =Il|Nb>
setTotalCount(totalCount); ':}\4j&{E
setItems(items); w*!aZ,P
setStartIndex(0); RyN s6
} I|J/F}@p
f-d1KNY
public PaginationSupport(List items, int mt`.6Xz~
h$=2 p5'-
totalCount, int startIndex){ 8[>zG2
setPageSize(PAGESIZE); W`&hp6Jq
setTotalCount(totalCount); \f)#>+X-
setItems(items); 6,uX,X5
setStartIndex(startIndex); yBRC*0+Vy
} m3ff;,
4sM.C9W
public PaginationSupport(List items, int 4~=l}H>&
0ksa
totalCount, int pageSize, int startIndex){ ?}7p"3j'z
setPageSize(pageSize); -F92 -jBM4
setTotalCount(totalCount); 66 Tpi![
setItems(items); 7?t6UPf
setStartIndex(startIndex); ^J d
r>@
} f X)#=c|5
Wvqhl
'J
publicList getItems(){ Hefg[$m
return items; p8Q1-T3v
} Gc!x|V;T
f-2c0Bi
publicvoid setItems(List items){ 1U\z5$V
this.items = items; "mNq&$
} ^t"'rD-I
X?$_Sd"G+5
publicint getPageSize(){ <t,x RBk
return pageSize; ZB&6<uw
} MfQ!6zE
fAmz4
publicvoid setPageSize(int pageSize){ y==CTY@
this.pageSize = pageSize; $SE^S
} 8Eq7Sa
EzIGz[
publicint getTotalCount(){ "vGW2~*)
return totalCount; D-4f.Tq4#
} JLi|Td"1%
ty`DJO=Omj
publicvoid setTotalCount(int totalCount){ ;6wA"
if(totalCount > 0){ 'QIqBU'~
this.totalCount = totalCount; bF(f*u
int count = totalCount / 03(4 x'z
o]:9')5^
pageSize; 4&f3%eTi
if(totalCount % pageSize > 0) Rh |nP&6
count++; LK"69Qx?5q
indexes = newint[count]; * 4Izy14e
for(int i = 0; i < count; i++){ yZ`wfj$Jj
indexes = pageSize * Y<rU#Z #T
@o6L6Y0Naa
i; T#)P`q
} A9JdU&
}else{ ^H'\"9;7
this.totalCount = 0; p^_yU_
} kwA$Z!Rn
} JG,%qFlk
MWL%
Bz
publicint[] getIndexes(){ 9mFE?J
return indexes; Q^(b)>?r;
} Yrn)VV[)h
&M'*6A
publicvoid setIndexes(int[] indexes){ [mHdG2X
this.indexes = indexes; ,: ->ErP
} (~en (
^VACf|0
publicint getStartIndex(){ P2*<GjV`S/
return startIndex; "T"h)L<
} ##o#eZq:"
veRm2LSP
publicvoid setStartIndex(int startIndex){ h-D}'R
if(totalCount <= 0) +U.I( 83F
this.startIndex = 0; 7!$^r$t
elseif(startIndex >= totalCount) ~= -RK$=
this.startIndex = indexes F3N6{ysK#
d:{O\
[indexes.length - 1]; h=%_Ao<x
elseif(startIndex < 0) VQ{fne<
this.startIndex = 0; +'@Dz9:>
else{ +KEWP\r
this.startIndex = indexes _7)n(1h[3b
->{KVPHe{
[startIndex / pageSize]; +H2-ZXr
} 3Le{\}-$.
} w'3iY,_ufC
-S+zmo8
publicint getNextIndex(){ {u9}bx'<
int nextIndex = getStartIndex() + f4Rf?w*
p[lA\@l[
pageSize; GDy9qUV
if(nextIndex >= totalCount) kM@zyDn,
return getStartIndex(); zA"`!}*
else i2^>vYCsl
return nextIndex; {vO9ptR;
} RAK-UN
{
buy"X4
publicint getPreviousIndex(){ W 8!Qv8rf
int previousIndex = getStartIndex() - }-3mPy(*%
Uv~QUL3>
pageSize; T"}vAG( .O
if(previousIndex < 0) |B2+{@R
return0; Z*2Vpnqh\
else TvQo?
return previousIndex; qcGK2Qx
} ff1c/c/
',4iFuY
} K!]/(V(}
C\/L v.
O<;3M'y\
0,8okAH
抽象业务类 vFK<J Sk!
java代码: j9OG\m
d&s9t;@=
7(
2{'r
/** Y7[jqb1D
* Created on 2005-7-12 -\n@%$M]G
*/ P_#bow
package com.javaeye.common.business; l?^4!&Nm
!1Cy$}w
import java.io.Serializable; x7x\Y(@
import java.util.List; 'anG:=
lR6x3C
H@
import org.hibernate.Criteria; pQ<Y:-`c
import org.hibernate.HibernateException; ig':%2V/
import org.hibernate.Session; Oh\<VvZuN
import org.hibernate.criterion.DetachedCriteria; _Z,\Vw:\F
import org.hibernate.criterion.Projections; {3{"8-18
import ^B2
-)
a"g!e^
org.springframework.orm.hibernate3.HibernateCallback; *%t^;&x?
import M>8A\;"
%\Mo-Ow!\
org.springframework.orm.hibernate3.support.HibernateDaoS a,#j =
B[?CbU
upport; Y,e B|
Sw^u3
import com.javaeye.common.util.PaginationSupport; ~PahoRS
Ziu]'#
public abstract class AbstractManager extends nSAdCJ;4
wtV#l4
HibernateDaoSupport { fCobzDy
g]yBA7/S"
privateboolean cacheQueries = false; yU}qOgXx
8d-t|HkN
privateString queryCacheRegion; df #$9-
TSWM
|#u':
publicvoid setCacheQueries(boolean JNUt$h
zeC
RK+-
cacheQueries){ u4%Pca9(=
this.cacheQueries = cacheQueries; f/Bp.YwL
} o W Nh@C
tWa)_y
publicvoid setQueryCacheRegion(String 8rS:5:Hi
X~,aNRy
queryCacheRegion){ _v=SH$O+
this.queryCacheRegion = Q=20IQp
z4]api(xZ
queryCacheRegion; E6gI,f/p0X
} aC.~&MxFC
9dUravC7
publicvoid save(finalObject entity){ t#pS{.I
getHibernateTemplate().save(entity); z}ddqZ27G$
} qF-@V25P
Um-[~-
publicvoid persist(finalObject entity){ 7 uKY24
getHibernateTemplate().save(entity); k<{{*
} spPNr
oVfLnI;
publicvoid update(finalObject entity){ o;R2p $
getHibernateTemplate().update(entity); hL;(C)(
} FXN/Yq
><$d$(
publicvoid delete(finalObject entity){ in- HUG
getHibernateTemplate().delete(entity); "#oHYz3D
} dl@%`E48w
ouFYvtF g
publicObject load(finalClass entity, l
+OFw)8od
u=7J/!H7^
finalSerializable id){ qC:raH_:
return getHibernateTemplate().load QTXt8I
y)!5R 3b
(entity, id); os={PQRD
} g($DdKc|g
}$Tl ?BRpU
publicObject get(finalClass entity, |NC*7/}
:G2k5xD/E
finalSerializable id){ ~`\?"s:
return getHibernateTemplate().get |pp*|v1t
sCk?
(entity, id); %)I{%~u0
} s<eb;Z2D
91g2A|
publicList findAll(finalClass entity){ tL)t" i
return getHibernateTemplate().find("from 2Kyl/C,
Zk"eA'"\
" + entity.getName()); [^e%@TV>d
} 7 Vo$(kj
kB|B
publicList findByNamedQuery(finalString $m1z-i;/
=mpVYA
namedQuery){ v`zJb00DT
return getHibernateTemplate D9
|n)f
MET' (m
().findByNamedQuery(namedQuery); $79=lEn,
} [8,yF
D_U
^ ALly2
publicList findByNamedQuery(finalString query, `a/%W4
Tewb?:
finalObject parameter){ @jSYB+D
return getHibernateTemplate sVv xHkt@
E5xzy/ZQ
().findByNamedQuery(query, parameter); 1Z~)RJ<D
} ~r`9+b[9{
iS Gq!D
publicList findByNamedQuery(finalString query, SB|Qa}62
'~&X wZ&
finalObject[] parameters){ ,\ k(x>oy
return getHibernateTemplate 4.=3M
Vq\`+&A
().findByNamedQuery(query, parameters); S` ;?z
} X/2&!O
}O^zl#
publicList find(finalString query){ !&/{E
[
return getHibernateTemplate().find *HO}~A%Lx
dA0.v+Foz"
(query); @EpIh&
} X+S9{X#Cm
<55g3>X
publicList find(finalString query, finalObject C/kW0V7
"C19b:4H
parameter){ lfz2~Si5A
return getHibernateTemplate().find fb8g7H|
$[&*Bj11Yg
(query, parameter); G<f@#[$'
} a]/>ra5{
vbBc}G"w
public PaginationSupport findPageByCriteria FCuB\Q
3`.7<f`
(final DetachedCriteria detachedCriteria){ 2.zsCu4lj.
return findPageByCriteria %_L\z*+
/8g^T")
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Q&g^c2
} [[Fx[
>wBJy4:
public PaginationSupport findPageByCriteria V=V:SlS9|
M&Uj^K1
(final DetachedCriteria detachedCriteria, finalint 3]UUG
RUT,Y4 b
startIndex){ ez^@NK
return findPageByCriteria ^[XYFQ TL
lM{
+!-G,
(detachedCriteria, PaginationSupport.PAGESIZE, NchXt6$i9
xJZ>uTN
startIndex); <'Wo@N7
} J<maQ6p
>U*T0FL7
public PaginationSupport findPageByCriteria ? 1$fJ3
D'A/wG
(final DetachedCriteria detachedCriteria, finalint !@'6)/
oMTf"0EIW
pageSize, `~;rblo;
finalint startIndex){ @reeO=
return(PaginationSupport) BT"42#7_
aKuSd3E@#
getHibernateTemplate().execute(new HibernateCallback(){ h{p=WWK
publicObject doInHibernate >ByXB!Wi+
``e$AS
(Session session)throws HibernateException { *nsAgGKKM^
Criteria criteria = oDYRQozo>
GBFtr
detachedCriteria.getExecutableCriteria(session); [7S} g
int totalCount = _DNHc*
j;3[KLmuK%
((Integer) criteria.setProjection(Projections.rowCount o1Q7Th
#x3ujJ
()).uniqueResult()).intValue(); FE!lok
criteria.setProjection p>;_e(
`zXO_@C
(null); #ap9Yoyk\
List items = WT`4s
D{4YxR
PX
criteria.setFirstResult(startIndex).setMaxResults [$"n^5_~
pV,P|>YTf
(pageSize).list(); GJp85B!PlO
PaginationSupport ps = (tGY%oT"
P(73!DT+
new PaginationSupport(items, totalCount, pageSize, oK%K}{`
P7MeX(Tay
startIndex); V6#K2
return ps; S'B|>!z@
} Xo*%/0q'
}, true); _({A\}Q|
} mJ`A_0
{aJJ`t
public List findAllByCriteria(final _}VloiY
)V:]g\t
DetachedCriteria detachedCriteria){
n>`as
return(List) getHibernateTemplate 'ao"9-c
s)2fG\1
().execute(new HibernateCallback(){ {aC!~qR
publicObject doInHibernate -O!Zxg5x
y>|{YWbp?
(Session session)throws HibernateException { m[@Vf9
Criteria criteria = adi[-L#
9>rPe1iv
detachedCriteria.getExecutableCriteria(session); FEW_bP/4
return criteria.list(); z2hc.29t
}
\$OF1i@
}, true); ${nX:!)
} 3LTcEd
n`
TSu$
public int getCountByCriteria(final -x4X O`b
0,Y5KE{
DetachedCriteria detachedCriteria){ AT)a :i
Integer count = (Integer) a~!G%})'a
-yg?V2
getHibernateTemplate().execute(new HibernateCallback(){ VA%Un,5h
publicObject doInHibernate 4bEf
Z)xaJGbw
(Session session)throws HibernateException {
ld7v3:M
Criteria criteria = n?urE-_
-"[<ek
detachedCriteria.getExecutableCriteria(session); A4?+T+#d
return lP!;3iJ B
WJ9cZL
criteria.setProjection(Projections.rowCount ^3FE\V/=
{;
>Q.OX@
()).uniqueResult(); P7f,OY<@%o
} f5==";eP
}, true); ?k|H3;\
return count.intValue(); FSbHn{@
} pdEiqLhH
} ;kJA'|GX
eDZ8w
?
j
9|5*
eBO@7F$
z>06hBv(?Y
"AhTH.ZP
用户在web层构造查询条件detachedCriteria,和可选的 G>+1*\c
NAzX". g
startIndex,调用业务bean的相应findByCriteria方法,返回一个 k') E/n
FG!X"<he
PaginationSupport的实例ps。 fQ=MJ7l
KyO8A2'U
ps.getItems()得到已分页好的结果集 $VQtwuYt
ps.getIndexes()得到分页索引的数组 =FT98H2*|
ps.getTotalCount()得到总结果数 n7YEG-J
ps.getStartIndex()当前分页索引 VCcr3Dx()F
ps.getNextIndex()下一页索引 *I0-O*Xr
ps.getPreviousIndex()上一页索引 rUjdq/I:Z
`[YngYw
}O4se"xK
Ep4Hqx $
FHPXu59u
!HJ$UG/\
AisN@
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 leiW4Fj
_ZAch zV
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 `j9$T:`
}Y17*zp%
一下代码重构了。 M#@aB"@J>
M-uMZQe
我把原本我的做法也提供出来供大家讨论吧: tB'V
U`x bPQ
首先,为了实现分页查询,我封装了一个Page类: <d7V<&@o=
java代码: qJ_1*!!91
-gz0md|Y
h
!(>7/Gi
/*Created on 2005-4-14*/ S?0)1O
package org.flyware.util.page; ~/tKMS6T
2`=6 %s
/** S|GWcSg
* @author Joa 8%~t
* @lUlY2
*/ ARfRsPxr
publicclass Page { jRpdft
Us~ X9n_F
/** imply if the page has previous page */ @)8]e
S7
privateboolean hasPrePage; oT|m1aGE
yO>V/5`
/** imply if the page has next page */ Q:|w%L*E
privateboolean hasNextPage; m$$?icA
wp.TfKxw
/** the number of every page */ &VWlt2-R0h
privateint everyPage; m^{
xd2
[Id}4[={e
/** the total page number */ .#5l$['
privateint totalPage; WO,xMfK
c~dM`2J,
/** the number of current page */ S C_|A9
privateint currentPage; YJ2ro-X
5`E))?*"Pe
/** the begin index of the records by the current Z# Lx_*p]Q
8Xm@r#Oy5
query */ /CT(k1>
privateint beginIndex; R.1Xst &i
M}.b"
ljZ
=J|sbY"]
/** The default constructor */ c/u_KJFF-n
public Page(){ Eb.;^=x
Dr"/3xm
} mPVE?jnR^0
".2A9]_s
/** construct the page by everyPage O=jN&<rb
* @param everyPage DPJh5d
* */ MPRO
!45Z
public Page(int everyPage){ 3^G96]E
this.everyPage = everyPage; ]X" / yAn
} LBX%H GH
Wtv#h~jy9
/** The whole constructor */ [l[{6ZXt
public Page(boolean hasPrePage, boolean hasNextPage, "'eWn6O(
<4D%v"zRP
hr U :Wr
int everyPage, int totalPage, X_70]^XL
int currentPage, int beginIndex){ 3DoRE2}
this.hasPrePage = hasPrePage; ~/`X*n&
this.hasNextPage = hasNextPage; ?B4#f!X
this.everyPage = everyPage; SQKt}kDbM
this.totalPage = totalPage; =2oUZjA
this.currentPage = currentPage; vg5NY =O
this.beginIndex = beginIndex; B2hfD-h,>
} P&t;WPZ
DcFCKji
/** R^Bk]
* @return %N~;{!![p
* Returns the beginIndex. "oE* 9J?e
*/ K~>jApZ%
publicint getBeginIndex(){ ~5t?C<wo
return beginIndex; xtJAMo>g
} _IYY08&(r
t>U!Zal"
/** {of]/3=
* @param beginIndex 0:dB
9
* The beginIndex to set. xYR#%! M
*/ vbn>mg5
publicvoid setBeginIndex(int beginIndex){ a8h]n:!
this.beginIndex = beginIndex; G6Q4-kcK
} `Ei"_W
m,NMTyJoz
/** yzc pG6,
* @return BQ#jwu0e
* Returns the currentPage. <"I?jgo
*/ VC=6uB
publicint getCurrentPage(){ `$9L^Yg,4
return currentPage; 31 ]7z
} 4Vx+[8W
9U10d&M(
/** )Z:m)k>r;
* @param currentPage ~.Q4c*_b
* The currentPage to set. h3h8lt_|
*/ P{lh)m>
publicvoid setCurrentPage(int currentPage){ j<$R4A1
this.currentPage = currentPage; f8!l7{2%q
} %UmbDGDWI
lCE2SKj
/** h>tsis'N9
* @return [s %\.y(q
* Returns the everyPage. ?-{IsF^
*/ )[DpK=[N^p
publicint getEveryPage(){ ;xW{Ehq-h
return everyPage; eG^z*`**
} /'Bdq?!B&
XaGz].Sv
/** ype"7p\
* @param everyPage Y:%"K
* The everyPage to set. Q2$/e+
*/ <NL+9l R
publicvoid setEveryPage(int everyPage){ *eoq=,O
this.everyPage = everyPage; Ty}R^cy{d
} B'/Icg.T
X)NWX9^;'
/** t>@yv#
* @return D'?]yyrf
* Returns the hasNextPage. \I
xzdFF#
*/ YlB["@\[B
publicboolean getHasNextPage(){ 5@.zz"o.`
return hasNextPage; | /#'S&!U
} ;q&Z9lm
eU"mG3__
/** r
&c_4%y
* @param hasNextPage Zr R+QV
* The hasNextPage to set. vK`S!7x'&
*/ Ebbe=4
publicvoid setHasNextPage(boolean hasNextPage){ [Z% l.
this.hasNextPage = hasNextPage; <mn-=#)
} &X7ttB"#h
mN7&%Z
/** >2t
cEz%
* @return x/[8Wi,yB
* Returns the hasPrePage. K5+!(5V~
*/ %)dI2 J^Xf
publicboolean getHasPrePage(){ T*p|'Q`
return hasPrePage; L<"k7)k
} Cea"qNq=k
|H<|{{E
/** {!g?d<*
* @param hasPrePage Xv]*;Bq:SK
* The hasPrePage to set. hX %s]"
*/ TR|;,A[%v#
publicvoid setHasPrePage(boolean hasPrePage){ ZG!x$yi$
this.hasPrePage = hasPrePage; R$v i!0
} |M]sk?"^
-D$3!ccX
/** F1/6&u9I
* @return Returns the totalPage. 4g S[D
* 7!mJhgGc
*/ 9c:5t'Qt5.
publicint getTotalPage(){ I S.F
return totalPage; 4'_L W?DS
} s"#CkG
M$gvq:}kt
/** my=*zziN
* @param totalPage ?!_u,sT
* The totalPage to set. YlG;A\]k
*/ E#8J+7
publicvoid setTotalPage(int totalPage){ .!!79 6hS
this.totalPage = totalPage; q^u6f?B
} -.^@9
a>
?V.ig
} W6hNJb
'wegipK~R
QZqpF9Eu
ZyZl\\8U
KhLg*EL
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 fdg[{T4:
XlE$.
个PageUtil,负责对Page对象进行构造: osI- o~#>
java代码: jg7d7{{SB
aYqqq|
9 Zs#Ky/
/*Created on 2005-4-14*/ (di)`D5Q
package org.flyware.util.page; OE5 X8DqQe
d5N)^\z
import org.apache.commons.logging.Log; ;&/sj-xJ2
import org.apache.commons.logging.LogFactory; [))gn
A!n~8zcmp}
/** X9p+a,
* @author Joa aA7S'[NjB
* Yjpb+}
*/ ;|2Uf
publicclass PageUtil { S6=\r{V
27}.s0{D
privatestaticfinal Log logger = LogFactory.getLog 4u7c7K>\Y
&8R-C[A
(PageUtil.class); (*LTqC
oB hL}r
/** 6(!,H<bON
* Use the origin page to create a new page GZ;Z
* @param page <m-Ni
* @param totalRecords hB?U5J
* @return -i| /JH
*/ 4;B=Qoxe
publicstatic Page createPage(Page page, int o}5'v^"6,
clij|?O
totalRecords){ d@_'P`%-
return createPage(page.getEveryPage(), 2
rbX8Y
{jq^hM!TEy
page.getCurrentPage(), totalRecords); sE(X:[Am
} !pE>O-| K
$`cy'ZaF
/** G7Edi;y/{
* the basic page utils not including exception THegPD67J
C.DoXE7
handler Pl`Bd0
* @param everyPage +_vm\]4
* @param currentPage h8Dtq5t4
* @param totalRecords BV_a-\Sa=
* @return page 0TuNA\Ug+
*/ LIm$Wl1U
publicstatic Page createPage(int everyPage, int P,s)2 s'nZ
<"j"h=tm}
currentPage, int totalRecords){ d#M?lS>
everyPage = getEveryPage(everyPage); Qe'PAN=B
currentPage = getCurrentPage(currentPage); #,Fx@3y\a
int beginIndex = getBeginIndex(everyPage, z.Ve#~\
"N=&4<]I5
currentPage); ]lG_rGw
int totalPage = getTotalPage(everyPage, exa}dh/uC
j$JV(fz
totalRecords); ]xVL11p
boolean hasNextPage = hasNextPage(currentPage, -v/?>
Hf`&&
totalPage); ]c~ rPi
boolean hasPrePage = hasPrePage(currentPage); \f<thd*bC
=#PudF.\
returnnew Page(hasPrePage, hasNextPage, f(zuRM^5
everyPage, totalPage, +L<w."WG
currentPage, pB{ f-M:D
Qcy+ {j]
beginIndex); _s=Pk[e
} 3mnL V*aRt
! a8h
privatestaticint getEveryPage(int everyPage){ Vo58Nz:%
return everyPage == 0 ? 10 : everyPage; yp7,^l
} >LRaIU>
3k|~tVM
privatestaticint getCurrentPage(int currentPage){ EJ[iOYx
return currentPage == 0 ? 1 : currentPage; gP"Mu#/D
} ".7KEnx
/ux#U]x
privatestaticint getBeginIndex(int everyPage, int B3i=pcef
'e8d["N
currentPage){ @a{v>)
return(currentPage - 1) * everyPage; S@rsQ@PA
} l.LFlwt
!&:.Uh
privatestaticint getTotalPage(int everyPage, int +[go7A$5
ZYp-dlEXq
totalRecords){ e?'k[ES^
int totalPage = 0; .LVOaxT
-2mOgv
if(totalRecords % everyPage == 0) F$pd]F!#
totalPage = totalRecords / everyPage; & m ";D
else -O,O<tOm
totalPage = totalRecords / everyPage + 1 ; P#'DG W&W0
\6PIw-)
return totalPage; g\mrRZ/?
} SGT-B.
"}Sid+)<
privatestaticboolean hasPrePage(int currentPage){ f0s<Y
return currentPage == 1 ? false : true; ^IegR>
} OA5md9P;d
T;vPR,]rz
privatestaticboolean hasNextPage(int currentPage, JT+lWhy
LZ<(:S
int totalPage){ ur_"m+
return currentPage == totalPage || totalPage == /Gu2@m[r
Ik2szXh[J
0 ? false : true; N4JL.(m){I
} F[qIfh4
YuZ
x#xO {
} ?p\II7
7m)ykq:?
_|V+["IS
V,%5
hl'&
<EE+
S#z
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。 4% .2=
lbXkZ ,
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 Z.#glmw^=R
rcb/X`l=
做法如下: rG'k<X~7
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?z36mj"`o
+c2=*IA/
的信息,和一个结果集List: Woy[V
java代码: ~\(>m=|C:H
~k_zMU-1
C4K&flk]
/*Created on 2005-6-13*/ 9YsO+7[
package com.adt.bo; [A/+tv
Gb)iB
import java.util.List; Ud?d.
~.=!5Ry
import org.flyware.util.page.Page; z.F+$6
[==Z1Q;=
/** ]3cf}Au
* @author Joa
SCC/
<o
*/ :JG}%
publicclass Result { *j; r|P;g
9>Z#o<*_/
private Page page; ])";Z
,>EY9j
private List content; 4'e8VI0
'F<e )D?
/** @g5]w&o_
* The default constructor bWzc=03
*/ -m-WUox4"
public Result(){ h |
super(); R$3+ 01j|
} y#W8] <dS"
:fQ*'m,
/** ~./u0E
* The constructor using fields \crmNH)3
* X-WvKH(=w
* @param page s,q!(\{Pv
* @param content R^C;D2
*/ 8+b3u05
public Result(Page page, List content){ R')GQ.yYq
this.page = page; O&RHCR-\
this.content = content; >R0j<:p :
} &3/H
P)*<]
YLd%"H $n
/** /{}
]Hu
* @return Returns the content. I!#^F1p1
*/ 6E&