资源适配器的开发
开发资源适配器，我们从最基本的连接(Connection)类开始。
DemoConnection
DemoConnection扩展了CCI的Connection接口，它由客户端程序使用，代表了到EIS的"虚拟"连接，通过这个"虚拟"的连接客户端可以调用EIS。需要注意的是，虚拟连接关闭时，物理连接不一定关闭。DemoConnection定义了资源适配器所实现的业务方法。如例程2所示。
例程2 DemoConnection的代码
1 package com.hellking.jca;
2 import javax.resource.cci.Connection;
3 import javax.resource.ResourceException;
4 public interface DemoConnection extends Connection
5 {
6 //业务方法
7 public String sayHello(String name)throws ResourceException;
8 }
9
2 import javax.resource.cci.Connection;
3 import javax.resource.ResourceException;
4 public interface DemoConnection extends Connection
5 {
6 //业务方法
7 public String sayHello(String name)throws ResourceException;
8 }
9
DemoConnectionImpl
DemoConnectionImpl是DemoConnection的实现类，它通过ManagedConnection来完成具体的业务方法。ManagedConnection是代表到EIS的物理连接，将在后面介绍。
例程3 DemoConnectionImpl大代码
1 package com.hellking.jca;
2 import javax.resource.*;
3 import javax.resource.spi.*;
4 import javax.resource.cci.*;
5 import javax.security.auth.*;
6 import java.util.*;
7 import java.io.*;
8 //连接实现类，它通过DemoManagedConnection来完成具体的任务
9 public class DemoConnectionImpl implements DemoConnection
10 {
11 protected PrintWriter out;//logOut
12 protected DemoManagedConnection demoManagedConnection;
13
14 //关闭连接，释放资源
15 public void close()
16 {
17 if (demoManagedConnection == null) return;
18 demoManagedConnection.removeConnection(this);
19 demoManagedConnection.connectionClosedEvent();
20 demoManagedConnection = null;
21 }
22 //返回和这个连接关联的被管理连接
23 public DemoManagedConnection getManager()
24 {
25 return demoManagedConnection;
26 }
27 //设置和这个连接关联的被管理连接
28 public void setManager (DemoManagedConnection manager)
29 {
30 this.demoManagedConnection =manager;
31 }
32
33 //业务方法，它通过调用被管理的连接来实现。
34 public String sayHello(String name)throws ResourceException
35 {
36 return demoManagedConnection.sayHello (name);
37 }
38
39 //使连接无效
40 public void invalidate()
41 {
42 demoManagedConnection = null;
43 }
44 public void setLogWriter(PrintWriter out)
45 {
46 this.out = out;
47 }
48
49 public PrintWriter getLogWriter()
50 {
51 return out;
52 }
53
54 public ConnectionMetaData getMetaData()
55 {
56 return null;
57 }
58 public ResultSetInfo getResultSetInfo()
59 {
60 return null;
61 }
62 public javax.resource.cci.LocalTransaction getLocalTransaction()
63 {
64 return null;
65 }
66 public Interaction createInteraction()
67 {
68 return null;
69 }
70
71 }
72
2 import javax.resource.*;
3 import javax.resource.spi.*;
4 import javax.resource.cci.*;
5 import javax.security.auth.*;
6 import java.util.*;
7 import java.io.*;
8 //连接实现类，它通过DemoManagedConnection来完成具体的任务
9 public class DemoConnectionImpl implements DemoConnection
10 {
11 protected PrintWriter out;//logOut
12 protected DemoManagedConnection demoManagedConnection;
13
14 //关闭连接，释放资源
15 public void close()
16 {
17 if (demoManagedConnection == null) return;
18 demoManagedConnection.removeConnection(this);
19 demoManagedConnection.connectionClosedEvent();
20 demoManagedConnection = null;
21 }
22 //返回和这个连接关联的被管理连接
23 public DemoManagedConnection getManager()
24 {
25 return demoManagedConnection;
26 }
27 //设置和这个连接关联的被管理连接
28 public void setManager (DemoManagedConnection manager)
29 {
30 this.demoManagedConnection =manager;
31 }
32
33 //业务方法，它通过调用被管理的连接来实现。
34 public String sayHello(String name)throws ResourceException
35 {
36 return demoManagedConnection.sayHello (name);
37 }
38
39 //使连接无效
40 public void invalidate()
41 {
42 demoManagedConnection = null;
43 }
44 public void setLogWriter(PrintWriter out)
45 {
46 this.out = out;
47 }
48
49 public PrintWriter getLogWriter()
50 {
51 return out;
52 }
53
54 public ConnectionMetaData getMetaData()
55 {
56 return null;
57 }
58 public ResultSetInfo getResultSetInfo()
59 {
60 return null;
61 }
62 public javax.resource.cci.LocalTransaction getLocalTransaction()
63 {
64 return null;
65 }
66 public Interaction createInteraction()
67 {
68 return null;
69 }
70
71 }
72
