JdbcInterceptor (Apache Tomcat 9.0.0.M9 API Documentation)

java.lang.Object
- org.apache.tomcat.jdbc.pool.JdbcInterceptor

All Implemented Interfaces:

InvocationHandler

Direct Known Subclasses:

AbstractCreateStatementInterceptor, ConnectionState, DisposableConnectionFacade, ProxyConnection, TrapException
```
public abstract class JdbcInterceptor
extends Object
implements InvocationHandler
```
Abstract class that is to be extended for implementations of interceptors. Everytime an operation is called on the Connection object the invoke(Object, Method, Object[]) method on the interceptor will be called. Interceptors are useful to change or improve behavior of the connection pool.
Interceptors can receive a set of properties. Each sub class is responsible for parsing the properties during runtime when they are needed or simply override the setProperties(Map) method. Properties arrive in a key-value pair of Strings as they were received through the configuration. This method is called once per cached connection object when the object is first configured.

Version:

1.0

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`CLOSE_VAL` `Connection.close()` method name
`static String`	`EQUALS_VAL` `Object.equals(Object)`
`static String`	`GETCONNECTION_VAL` `PooledConnection.getConnection()` method name
`static String`	`HASHCODE_VAL` `Object.hashCode()`
`static String`	`ISCLOSED_VAL` `Connection.isClosed()` method name
`static String`	`ISVALID_VAL` `Connection.isValid(int)` method name
`static String`	`ISWRAPPERFOR_VAL` `Wrapper.isWrapperFor(Class)` method name
`protected Map<String,PoolProperties.InterceptorProperty>`	`properties` Properties for this interceptor.
`static String`	`TOSTRING_VAL` `Object.toString()` method name
`static String`	`UNWRAP_VAL` `Wrapper.unwrap(Class)` method name

Constructor Summary

Constructors
Constructor and Description

JdbcInterceptor()
Public constructor for instantation through reflection

Constructors
Constructor and Description
`JdbcInterceptor()` Public constructor for instantation through reflection

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`compare(String methodName, Method method)` Compares a method name (String) to a method (Method) `compare(String,String)` Uses reference comparison unless the useEquals property is set to true
`boolean`	`compare(String name1, String name2)` Performs a string comparison, using references unless the useEquals property is set to true.
`void`	`disconnected(ConnectionPool parent, PooledConnection con, boolean finalizing)` Called when `Connection.close()` is called on the underlying connection.
`JdbcInterceptor`	`getNext()` Returns the next interceptor in the chain
`Map<String,PoolProperties.InterceptorProperty>`	`getProperties()` Returns the properties configured for this interceptor
`Object`	`invoke(Object proxy, Method method, Object[] args)` Gets invoked each time an operation on `Connection` is invoked.
`boolean`	`isUseEquals()`
`void`	`poolClosed(ConnectionPool pool)` This method is invoked by a connection pool when the pool is closed.
`void`	`poolStarted(ConnectionPool pool)` This method is invoked by a connection pool when the pool is first started up, usually when the first connection is requested.
`abstract void`	`reset(ConnectionPool parent, PooledConnection con)` Gets called each time the connection is borrowed from the pool This means that if an interceptor holds a reference to the connection the interceptor can be reused for another connection.
`void`	`setNext(JdbcInterceptor next)` configures the next interceptor in the chain
`void`	`setProperties(Map<String,PoolProperties.InterceptorProperty> properties)` Called during the creation of an interceptor The properties can be set during the configuration of an interceptor Override this method to perform type casts between string values and object properties
`void`	`setUseEquals(boolean useEquals)` Set to true if string comparisons (for the `compare(String, Method)` and `compare(String, String)` methods) should use the Object.equals(Object) method The default is false

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - CLOSE_VAL
```
public static final String CLOSE_VAL
```
    Connection.close() method name
    
    See Also:
    
    Constant Field Values
  - TOSTRING_VAL
```
public static final String TOSTRING_VAL
```
    Object.toString() method name
    
    See Also:
    
    Constant Field Values
  - ISCLOSED_VAL
```
public static final String ISCLOSED_VAL
```
    Connection.isClosed() method name
    
    See Also:
    
    Constant Field Values
  - GETCONNECTION_VAL
```
public static final String GETCONNECTION_VAL
```
    PooledConnection.getConnection() method name
    
    See Also:
    
    Constant Field Values
  - UNWRAP_VAL
```
public static final String UNWRAP_VAL
```
    Wrapper.unwrap(Class) method name
    
    See Also:
    
    Constant Field Values
  - ISWRAPPERFOR_VAL
```
public static final String ISWRAPPERFOR_VAL
```
    Wrapper.isWrapperFor(Class) method name
    
    See Also:
    
    Constant Field Values
  - ISVALID_VAL
```
public static final String ISVALID_VAL
```
    Connection.isValid(int) method name
    
    See Also:
    
    Constant Field Values
  - EQUALS_VAL
```
public static final String EQUALS_VAL
```
    Object.equals(Object)
    
    See Also:
    
    Constant Field Values
  - HASHCODE_VAL
```
public static final String HASHCODE_VAL
```
    Object.hashCode()
    
    See Also:
    
    Constant Field Values
  - properties
```
protected Map<String,PoolProperties.InterceptorProperty> properties
```
    Properties for this interceptor.
- Constructor Detail
  - JdbcInterceptor
```
public JdbcInterceptor()
```
    Public constructor for instantation through reflection
- Method Detail
  - invoke
```
public Object invoke(Object proxy,
                     Method method,
                     Object[] args)
              throws Throwable
```
    Gets invoked each time an operation on Connection is invoked.
    
    Specified by:
    
    invoke in interface InvocationHandler
    
    Throws:
    
    Throwable
  - getNext
```
public JdbcInterceptor getNext()
```
    Returns the next interceptor in the chain
    
    Returns:
    
    the next interceptor in the chain
  - setNext
```
public void setNext(JdbcInterceptor next)
```
    configures the next interceptor in the chain
    
    Parameters:
    
    next - The next chain item
  - compare
```
public boolean compare(String name1,
                       String name2)
```
    Performs a string comparison, using references unless the useEquals property is set to true.
    
    Parameters:
    
    name1 - The first name
    
    name2 - The second name
    
    Returns:
    
    true if name1 is equal to name2 based on useEquals
  - compare
```
public boolean compare(String methodName,
                       Method method)
```
    Compares a method name (String) to a method (Method) compare(String,String) Uses reference comparison unless the useEquals property is set to true
    
    Parameters:
    
    methodName - The method name
    
    method - The method
    
    Returns:
    
    true if the name matches
  - reset
```
public abstract void reset(ConnectionPool parent,
                           PooledConnection con)
```
    Gets called each time the connection is borrowed from the pool This means that if an interceptor holds a reference to the connection the interceptor can be reused for another connection.
    This method may be called with null as both arguments when we are closing down the connection.
    
    Parameters:
    
    parent - - the connection pool owning the connection
    
    con - - the pooled connection
  - disconnected
```
public void disconnected(ConnectionPool parent,
                         PooledConnection con,
                         boolean finalizing)
```
    Called when Connection.close() is called on the underlying connection. This is to notify the interceptors, that the physical connection has been released. Implementation of this method should be thought through with care, as no actions should trigger an exception.
    
    Parameters:
    
    parent - - the connection pool that this connection belongs to
    
    con - - the pooled connection that holds this connection
    
    finalizing - - if this connection is finalizing. True means that the pooled connection will not reconnect the underlying connection
  - getProperties
```
public Map<String,PoolProperties.InterceptorProperty> getProperties()
```
    Returns the properties configured for this interceptor
    
    Returns:
    
    the configured properties for this interceptor
  - setProperties
```
public void setProperties(Map<String,PoolProperties.InterceptorProperty> properties)
```
    Called during the creation of an interceptor The properties can be set during the configuration of an interceptor Override this method to perform type casts between string values and object properties
    
    Parameters:
    
    properties - The properties
  - isUseEquals
```
public boolean isUseEquals()
```
    Returns:
    
    true if the compare method uses the Object.equals(Object) method false if comparison is done on a reference level
  - setUseEquals
```
public void setUseEquals(boolean useEquals)
```
    Set to true if string comparisons (for the compare(String, Method) and compare(String, String) methods) should use the Object.equals(Object) method The default is false
    
    Parameters:
    
    useEquals - true if equals will be used for comparisons
  - poolClosed
```
public void poolClosed(ConnectionPool pool)
```
    This method is invoked by a connection pool when the pool is closed. Interceptor classes can override this method if they keep static variables or other tracking means around. This method is only invoked on a single instance of the interceptor, and not on every instance created.
    
    Parameters:
    
    pool - - the pool that is being closed.
  - poolStarted
```
public void poolStarted(ConnectionPool pool)
```
    This method is invoked by a connection pool when the pool is first started up, usually when the first connection is requested. Interceptor classes can override this method if they keep static variables or other tracking means around. This method is only invoked on a single instance of the interceptor, and not on every instance created.
    
    Parameters:
    
    pool - - the pool that is being closed.

Class JdbcInterceptor

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

CLOSE_VAL

TOSTRING_VAL

ISCLOSED_VAL

GETCONNECTION_VAL

UNWRAP_VAL

ISWRAPPERFOR_VAL

ISVALID_VAL

EQUALS_VAL

HASHCODE_VAL

properties

Constructor Detail

JdbcInterceptor

Method Detail

invoke

getNext

setNext

compare

compare

reset

disconnected

getProperties

setProperties

isUseEquals

setUseEquals

poolClosed

poolStarted