org.objectweb.cjdbc.driver.protocol
Class TypeTag

java.lang.Object
  org.objectweb.cjdbc.driver.protocol.TypeTag

public final class TypeTag

extends java.lang.Object

This class implements protocol type tags with an internal String, but offers an abstract interface on top of it in order to be transparently substituted some day (with enums for instance).

Advantages of using string types is human-readability (debugging, trace analysis, etc.) and earlier detection in case of protocol corruption. Drawback maybe a small performance cost.

Check "the importance of being textual" - by Eric S. Raymond. http://www.faqs.org/docs/artu/ch05s01.html

Version:

1.0

Author:

Marc Herbert

Field Summary

static TypeTag	BACKEND_EXCEPTION Constant for an exception
static TypeTag	BIGDECIMAL Constant for a SQL/Java type
static TypeTag	BLOB Constant for a SQL/Java type
static TypeTag	BOOLEAN Constant for a SQL/Java type
static TypeTag	BYTE_ARRAY Constant for a SQL/Java type
static TypeTag	CLOB Constant for a SQL/Java type
static TypeTag	COL_TYPES Constant for a SQL structure
static TypeTag	CONTROLLER_READY Constant for internal protocol data
static TypeTag	CORE_EXCEPTION Constant for an exception
static TypeTag	DOUBLE Constant for a SQL/Java type
static TypeTag	EXCEPTION Constant for an exception
static TypeTag	FIELD Constant for a SQL structure
static TypeTag	FLOAT Constant for a SQL/Java type
static TypeTag	INTEGER Constant for a SQL/Java type
private java.lang.String	internalString
static TypeTag	LONG Constant for a SQL/Java type
static TypeTag	NOT_EXCEPTION used when there is no type ambiguity; no need to type
static TypeTag	NULL_RESULTSET Null ResultSet
static TypeTag	RESULTSET Constant for a SQL structure
static TypeTag	ROW Constant for a SQL structure
static TypeTag	SQL_DATE Constant for a SQL/Java type
static TypeTag	SQL_TIME Constant for a SQL/Java type
static TypeTag	SQL_TIMESTAMP Constant for a SQL/Java type
static TypeTag	STRING Constant for a SQL/Java type
private static java.lang.String	TPREFIX Actual Types ***
static TypeTag	TYPE_ERROR Constant for a SQL/Java type

Constructor Summary

	TypeTag(CJDBCInputStream in) Read/deserialize/construct a TypeTag from a stream.
private	TypeTag(java.lang.String init)

Method Summary

boolean	equals(java.lang.Object o) Deprecated.
boolean	equals(TypeTag b) Compares two TypeTags.
static TypeTag	jdbcToJavaObjectType(int jdbcType) Gives the standard JDBC type to Java Object type conversion according to table "JDBC type to Java Object Type" of the JDBC reference book.
void	sendToStream(CJDBCOutputStream out) Serialize "this" tag on the stream.
java.lang.String	toSring() Returns a string representation, useful for logging and debugging.

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

internalString

private java.lang.String internalString

TPREFIX

private static final java.lang.String TPREFIX

Actual Types ***

See Also:

Constant Field Values

TYPE_ERROR

public static final TypeTag TYPE_ERROR

Constant for a SQL/Java type

STRING

public static final TypeTag STRING

Constant for a SQL/Java type

BIGDECIMAL

public static final TypeTag BIGDECIMAL

Constant for a SQL/Java type

BOOLEAN

public static final TypeTag BOOLEAN

Constant for a SQL/Java type

INTEGER

public static final TypeTag INTEGER

Constant for a SQL/Java type

LONG

public static final TypeTag LONG

Constant for a SQL/Java type

FLOAT

public static final TypeTag FLOAT

Constant for a SQL/Java type

DOUBLE

public static final TypeTag DOUBLE

Constant for a SQL/Java type

BYTE_ARRAY

public static final TypeTag BYTE_ARRAY

Constant for a SQL/Java type

SQL_DATE

public static final TypeTag SQL_DATE

Constant for a SQL/Java type

SQL_TIME

public static final TypeTag SQL_TIME

Constant for a SQL/Java type

SQL_TIMESTAMP

public static final TypeTag SQL_TIMESTAMP

Constant for a SQL/Java type

CLOB

public static final TypeTag CLOB

Constant for a SQL/Java type

BLOB

public static final TypeTag BLOB

Constant for a SQL/Java type

RESULTSET

public static final TypeTag RESULTSET

Constant for a SQL structure

NULL_RESULTSET

public static final TypeTag NULL_RESULTSET

Null ResultSet

FIELD

public static final TypeTag FIELD

Constant for a SQL structure

COL_TYPES

public static final TypeTag COL_TYPES

Constant for a SQL structure

ROW

public static final TypeTag ROW

Constant for a SQL structure

NOT_EXCEPTION

public static final TypeTag NOT_EXCEPTION

used when there is no type ambiguity; no need to type

EXCEPTION

public static final TypeTag EXCEPTION

Constant for an exception

BACKEND_EXCEPTION

public static final TypeTag BACKEND_EXCEPTION

Constant for an exception

CORE_EXCEPTION

public static final TypeTag CORE_EXCEPTION

Constant for an exception

CONTROLLER_READY

public static final TypeTag CONTROLLER_READY

Constant for internal protocol data

Constructor Detail

TypeTag

private TypeTag(java.lang.String init)

TypeTag

public TypeTag(CJDBCInputStream in)
        throws java.io.IOException

Read/deserialize/construct a TypeTag from a stream.

Parameters:

in - input stream

Throws:

java.io.IOException - stream error

Method Detail

sendToStream

public void sendToStream(CJDBCOutputStream out)
                  throws java.io.IOException

Serialize "this" tag on the stream.

Parameters:

out - output stream

Throws:

java.io.IOException - stream error

equals

public boolean equals(java.lang.Object o)

Deprecated.

Calling this method is a bug, check the type of your argument.

Parameters:

o - compared object (which should be a TypeTag!)

Returns:

a buggy result

See Also:

Object.equals(java.lang.Object)

equals

public boolean equals(TypeTag b)

Compares two TypeTags.

Parameters:

b - compared TypeTag

Returns:

true if same value

toSring

public java.lang.String toSring()

Returns a string representation, useful for logging and debugging.

Returns:

string representation of the tag

jdbcToJavaObjectType

public static TypeTag jdbcToJavaObjectType(int jdbcType)

Gives the standard JDBC type to Java Object type conversion according to table "JDBC type to Java Object Type" of the JDBC reference book. (Table 47.9.3 in 2nd Edition, table 50.3 in 3rd edition). This is the conversion that the getObject() method of every JDBC driver should perform by default.

Parameters:

jdbcType - the JDBC type to convert

Returns:

the Java Object type resulting from the standard type conversion.

See Also:

Types