面向对象存取在Sybase ASE15.0中的解决方案
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<!-- [if gte mso 9]><![endif]--><!-- [if gte mso 9]><![endif]--><!-- [if !mso]><style> <!-- st1/:*{behavior:url(#ieooui) } --><!-- [endif]--><!-- /* Font Definitions */ @font-face {font-family:Wingdings; panose-1:5 0 0 0 0 0 0 0 0 0; mso-font-charset:2; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:0 268435456 0 0 -2147483648 0;} @font-face {font-family:宋体; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-alt:SimSun; mso-font-charset:134; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 135135232 16 0 262145 0;} @font-face {font-family:"/@宋体"; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-charset:134; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 135135232 16 0 262145 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; text-align:justify; text-justify:inter-ideograph; mso-pagination:none; font-size:10.5pt; mso-bidi-font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:宋体; mso-font-kerning:1.0pt;} /* Page Definitions */ @page {mso-page-border-surround-header:no; mso-page-border-surround-footer:no;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} /* List Definitions */ @list l0 {mso-list-id:2109228193; mso-list-type:hybrid; mso-list-template-ids:-260291210 104487470 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;} @list l0:level1 {mso-level-number-format:japanese-counting; mso-level-text:%1、; mso-level-tab-stop:42.0pt; mso-level-number-position:left; margin-left:42.0pt; text-indent:-21.0pt;} ol {margin-bottom:0cm;} ul {margin-bottom:0cm;} --><!-- [if gte mso 10]><style> <!-- /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} --><!-- [endif]--> </style>
数据库发展到今天，RDBMS(关系型数据库管理系统)和ODBMS(对象数据库管理系统)的界限已经变得模糊了，取而代之的是ORDBMS(对象关系型数据库管理系统)，对此，Oracle和DB2早年前都给出了自己的解决方案，即采用类似以下的抽象语法：
create typePoint is object
(
x int,
y int,
......
)
SybaseASE数据库，发展到现在15.0.3，在语法上，似乎并没有对这种抽象语法的直接支持。它采取的是另一种解决方案，即可以由用户直接定义一个Java类，让这个Java类直接成为一种抽象类型。那就是Sybase ASE数据库的Java服务选件，它是一种功能非常强大的组件。
比如，我们要提供一个解决方案，直接支持二维点Point类型的存取。怎么实现呢？
<!-- [if !supportLists]-->- 环境：
确定你的ASE数据库安装并拥有JavaOptions选项，如何得知呢？从SybaseCentral，连接到ASE服务器，右键à属性à版本à详细信息，可以得到如下信息：ASE_JAVA，有相应的版本和有效期信息，示例如下图，它支持Java，有效期到2020年1月20日。
<!-- [if gte mso 9]><![endif]--><!-- [if gte mso 9]><![endif]--><!-- [if !mso]><style> <!-- st1/:*{behavior:url(#ieooui) } --><!-- [endif]--><!-- /* Font Definitions */ @font-face {font-family:宋体; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-alt:SimSun; mso-font-charset:134; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 135135232 16 0 262145 0;} @font-face {font-family:"/@宋体"; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-charset:134; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 135135232 16 0 262145 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; text-align:justify; text-justify:inter-ideograph; mso-pagination:none; font-size:10.5pt; mso-bidi-font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:宋体; mso-font-kerning:1.0pt;} /* Page Definitions */ @page {mso-page-border-surround-header:no; mso-page-border-surround-footer:no;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --><!-- [if gte mso 10]><style> <!-- /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} --><!-- [endif]--> </style>
除此以外，还得让服务器启动时也支持Java。
D:/ASE150>isql-Usa-Psybase1
1>sp_configure "enable java", 1
2> go
(1 row affected)
配置选项改变.因为选项是静态的,AdaptiveServer必须重启,以使改动生效.
如果将 'enable java' 更改为 '1'，ASE 使用的内存量就能增加 580K。
(return status =0)
然后重启Sybase ASE数据库，即可生效，开始完全支持Java。
- <!-- [if gte mso 9]><![endif]--><!-- [if gte mso 9]><![endif]--><!-- /* Font Definitions */ @font-face {font-family:宋体; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-alt:SimSun; mso-font-charset:134; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 135135232 16 0 262145 0;} @font-face {font-family:"/@宋体"; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-charset:134; mso-generic-font-family:auto; mso-font-pitch:variable; mso-font-signature:3 135135232 16 0 262145 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; text-align:justify; text-justify:inter-ideograph; mso-pagination:none; font-size:10.5pt; mso-bidi-font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:宋体; mso-font-kerning:1.0pt;} /* Page Definitions */ @page {mso-page-border-surround-header:no; mso-page-border-surround-footer:no;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} /* List Definitions */ @list l0 {mso-list-id:2109228193; mso-list-type:hybrid; mso-list-template-ids:-260291210 104487470 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;} @list l0:level1 {mso-level-number-format:japanese-counting; mso-level-text:%1、; mso-level-tab-stop:42.0pt; mso-level-number-position:left; margin-left:42.0pt; text-indent:-21.0pt;} ol {margin-bottom:0cm;} ul {margin-bottom:0cm;} --><!-- [if gte mso 10]><style> <!-- /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} --><!-- [endif]--><span style="font-family: 宋体;">实现</span> </style>
首先，实现Point类。ASE支持Java对象类型，有一个条件，它必须实现了序列化接口。同时，编译为class文件时，编译的目标版本最好是1.1(为了保持兼容)。
Point类的一个简单实现如下：
public class Point implements java.io.Serializable
{
privatestatic final long serialVersionUID = -2550063311147977493L;
publicdouble _x;
publicdouble _y;
publicPoint()
{
_x = 0;
_y = 0;
}
publicPoint(double x, double y)
{
_x = x;
_y = y;
}
publicObject clone()
{
returnnew Point(_x, _y);
}
publicString toString()
{
return"(" + _x + ", " + _y + ")";
}
publicstatic double distance(Point a, Point b)
{
return(double)Math.sqrt((a._x - b._x)*(a._x - b._x)
+ (a._y - b._y)*(a._y - b._y));
}
publicstatic void main(String[] args)
{
Point a= new Point(1.0, 1.0);
Point b= new Point(5.0, 4.0);
System.out.println("a = " + a);
System.out.println("b = " + b);
System.out.println(Point.distance(a, b));
}
}
设定好jdk路径和classpath之后, 编译打包：
javac -g -target1.1 *.java
jar -cvf0Point.jar *.class
- <!-- [if gte mso 9]><![endif]--><!-- [if gte mso 9]><![endif]--><!-- [if gte mso 10]><style> <!-- /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} --><!-- [endif]--><p class="MsoNormal" style="margin-left: 42pt; text-indent: -21pt;"><!-- [if !supportLists]--><span lang="EN-US"><span>一、</span></span><!-- [endif]--><span style="font-family: 宋体;">装载</span><span lang="EN-US">java</span><span style="font-family: 宋体;">包到目标数据库</span></p> <p class="MsoNormal" style="margin-left: 21pt;"><span style="font-family: 宋体;">如下图所示：进入具体的数据库</span><span lang="EN-US">iihero</span><span style="font-family: Wingdings;" lang="EN-US"><span>à</span></span><span lang="EN-US">Java</span><span style="font-family: 宋体;">对象</span><span style="font-family: Wingdings;" lang="EN-US"><span>à</span></span><span lang="EN-US">Jar</span><span style="font-family: 宋体;">文件，右键</span><span style="font-family: Wingdings;" lang="EN-US"><span>à</span></span><span style="font-family: 宋体;">新建，即可把刚才打好的</span><span lang="EN-US">java</span><span style="font-family: 宋体;">包</span><span lang="EN-US">Point.jar</span><span style="font-family: 宋体;">装载到数据库</span><span lang="EN-US">iihero</span><span style="font-family: 宋体;">当中。</span></p> </style>
<!-- [if gte mso 9]><![endif]--><!-- [if gte mso 9]><![endif]--><!-- [if !mso]><style> <!-- st1/:*{behavior:url(#ieooui) } --><!-- [endif]--><!-- [if gte mso 10]><style> <!-- /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} --><!-- [endif]--> </style>
或者直接使用命令行：
D:/ASE150>instjava-D iihero -S SEANLAPTOP
-fE:/MyDocument/MYBOOKS/ASE/code/JavaSQL/Point.jar-update -j"Point" -Usa-P
其中-D指定目标数据库，-S指定服务名，-f指定已经编译好的java包，-j指定该包在数据库中的包名，-U指定连接数据库的用户名，-P指定密码。
<!-- [if !supportLists]-->一、<!-- [endif]-->面向对象应用的实际效果
D:/ASE150>isql-Uspring -Pspring1
1> use iihero
2> go
创建含对象类型Point列的表：
1> createtable testpoint(id int primary key, p Point)
2> go
使用对象特性插入数据并查询：
1> insertinto testpoint values (1, new Point(1.0, 1.0))
2> insertinto testpoint values (2, new Point(5.0, 4.0))
3> insertinto testpoint values (3, new Point(6.0, 13.0))
4> go
(1 row affected)
(1 row affected)
(1 row affected)
1> select *from testpoint
2> go
idp
-------------------------------------------------------------
1 (1.0, 1.0)
2 (5.0, 4.0)
3 (6.0, 13.0)
(3 rowsaffected)
直接取属性值：
1> select id,p>>_x, p>>_y from testpoint
2> go
id
----------- ------------------------------------------------------
1 1.000000 1.000000
2 5.000000 4.000000
3 6.000000 13.000000
(3 rowsaffected)
查询两点间的距离：
1> selecta.id, b.id, Point.distance(a.p, b.p) from testpoint a, testpoint b whe
re a.id <b.id
2> go
idid
----------- --------------------------------------
1 2 5.000000
1 3 13.000000
2 3 9.055385
(3 rowsaffected)
以距离作为条件查询点(查询两点间距离小于6.0的点对)：
1> selecta.id, b.id from testpoint a, testpoint b where Point.distance(a.p, b.p
) <6.0 anda.id > b.id
2> go
idid
----------- -----------
21
(1 row affected)
<!-- [if !supportLists]-->二、<!-- [endif]-->总结
在到ASE数据库服务器内部，它对Java类作了如下映射：
<!-- [if !supportLists]-->l<!-- [endif]-->select出对象列的值，就是Java对象的toString()值。
<!-- [if !supportLists]-->l<!-- [endif]-->静态方法可以直接在select语句里当作函数进行调用，如上例中的Point.distance()方法
<!-- [if !supportLists]-->l<!-- [endif]-->直接可以取类的成员值，如果那个成员是公有成员，并且有相应的SQL类型映射，如上例中的p>>_x,p>>_y，使用”>>”操作符来提取。
按照上述原理，用户完全使用内置的Java包实现非常复杂的逻辑，然后在SQL语句中直接加以利用。尤其是那种接近于面向对象数据库的应用。
总之，使用内置Java支持对对象类型的存取，是一种很直观易用的方法，也便于用户进行扩充。从这个角度来看，Sybase ASE也可以算是支持面向对象的数据存取了。