Package io.micronaut.serde.support

Class AbstractStreamDecoder

java.lang.Object

io.micronaut.serde.support.AbstractStreamDecoder

All Implemented Interfaces:

Decoder, AutoCloseable

Direct Known Subclasses:

AbstractDecoderPerStructureStreamDecoder, JsonParserDecoder, OracleJdbcJsonParserDecoder

@Internal
public abstract class AbstractStreamDecoder
extends Object
implements Decoder

Abstract base class for stream-based Decoders.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static enum	AbstractStreamDecoder.TokenType	The token type.
static interface	AbstractStreamDecoder.ValueDecoder<R>	Decoder function for a single value.

Constructor Summary

Constructors

Constructor	Description
AbstractStreamDecoder()

Method Summary

Modifier and Type	Method	Description
protected abstract String	coerceScalarToString(AbstractStreamDecoder.TokenType currentToken)	Decode any non-null scalar value (number, string or boolean) to its string representation.
protected void	consumeLeftElements(AbstractStreamDecoder.TokenType currentToken)	Consumes left elements.
protected abstract AbstractStreamDecoder.TokenType	currentToken()
final Object	decodeArbitrary()	Decodes the current state into an arbitrary object.
final Decoder	decodeArray(io.micronaut.core.type.Argument<?> type)	Start decoding an array.
protected AbstractStreamDecoder	decodeArray0(AbstractStreamDecoder.TokenType currentToken)	Decodes the array.
final BigDecimal	decodeBigDecimal()	Decodes a BigDecimal.
final BigInteger	decodeBigInteger()	Decodes a BigInteger.
final boolean	decodeBoolean()	Decodes a boolean.
Decoder	decodeBuffer()	Buffer the whole subtree of this value and return it as a new Decoder.
final byte	decodeByte()	Decodes a byte.
final char	decodeChar()	Decodes a char.
protected final <T> T	decodeCustom(AbstractStreamDecoder.ValueDecoder<T> readFunction)	Decode a custom type.
protected final <T> T	decodeCustom(AbstractStreamDecoder.ValueDecoder<T> readFunction, boolean callNext)	Decode a custom type.
final double	decodeDouble()	Decodes a double.
final float	decodeFloat()	Decodes a float.
final int	decodeInt()	Decodes a int.
String	decodeKey()	Decodes a key, if there are no more keys to decode returns null.
final long	decodeLong()	Decodes a long.
io.micronaut.json.tree.JsonNode	decodeNode()	Decodes the current state into a JsonNode.
final boolean	decodeNull()	Attempt to decode a null value.
protected final <T> T	decodeNumber(AbstractStreamDecoder.TokenType currentToken, AbstractStreamDecoder.ValueDecoder<T> fromNumberToken, Function<String,T> fromString, T zero, T one)	Decode a number type, applying all necessary coercions.
final Decoder	decodeObject(io.micronaut.core.type.Argument<?> type)	Decodes an object.
protected AbstractStreamDecoder	decodeObject0(AbstractStreamDecoder.TokenType currentToken)	Decodes the object.
final short	decodeShort()	Decodes a short.
String	decodeString()	Decodes a string.
void	finishStructure(boolean consumeLeftElements)
protected abstract Number	getBestNumber()	Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a Number value.
protected io.micronaut.json.tree.JsonNode	getBestNumberNode()	Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a numeric JsonNode.
protected abstract BigDecimal	getBigDecimal()	Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a BigDecimal value.
protected abstract BigInteger	getBigInteger()	Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a BigInteger value.
protected abstract boolean	getBoolean()	Decode the current AbstractStreamDecoder.TokenType.BOOLEAN value.
protected abstract String	getCurrentKey()	Get the current object field name.
protected abstract double	getDouble()	Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a double value.
protected int	getInteger()	Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a long value.
protected abstract long	getLong()	Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a long value.
protected abstract String	getString()	Decode the current AbstractStreamDecoder.TokenType.STRING value.
boolean	hasNextArrayValue()
protected abstract void	nextToken()	Move to the next token.
protected void	preDecodeValue(AbstractStreamDecoder.TokenType currentToken)	Should be called before attempting to decode a value.
protected abstract void	skipChildren()	If we are at a AbstractStreamDecoder.TokenType.START_OBJECT or AbstractStreamDecoder.TokenType.START_ARRAY, skip to the matching AbstractStreamDecoder.TokenType.END_OBJECT or AbstractStreamDecoder.TokenType.END_ARRAY.
final void	skipValue()	Skips the current value.
protected IOException	unexpectedToken(AbstractStreamDecoder.TokenType expected)

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.micronaut.serde.Decoder

close, createDeserializationException, decodeArray, decodeBigDecimalNullable, decodeBigIntegerNullable, decodeBooleanNullable, decodeByteNullable, decodeCharNullable, decodeDoubleNullable, decodeFloatNullable, decodeIntNullable, decodeLongNullable, decodeObject, decodeShortNullable, decodeStringNullable, finishStructure

Constructor Details

AbstractStreamDecoder

public AbstractStreamDecoder()

Method Details

currentToken

@Nullable
protected abstract AbstractStreamDecoder.TokenType currentToken()

Returns:

The current token.

nextToken

protected abstract void nextToken()
                           throws IOException

Move to the next token.

Throws:

IOException - if an unrecoverable error occurs

unexpectedToken

protected IOException unexpectedToken(AbstractStreamDecoder.TokenType expected)

Parameters:

expected - The token type that was expected in place of currentToken().

Returns:

The exception that should be thrown to signify an unexpected token.

preDecodeValue

protected void preDecodeValue(AbstractStreamDecoder.TokenType currentToken)

Should be called before attempting to decode a value. Has basic sanity checks, such as confirming we're not currently in a AbstractStreamDecoder.TokenType.KEY and that there's no child decoder currently running.

Parameters:

currentToken - The current token

finishStructure

public void finishStructure(boolean consumeLeftElements)
                     throws IOException

Specified by:

finishStructure in interface Decoder

Parameters:

consumeLeftElements - True to consume left elements

Throws:

IOException - If an unrecoverable error occurs

consumeLeftElements

protected void consumeLeftElements(AbstractStreamDecoder.TokenType currentToken)
                            throws IOException

Consumes left elements.

Parameters:

currentToken - The current token

Throws:

IOException

hasNextArrayValue

public boolean hasNextArrayValue()

Specified by:

hasNextArrayValue in interface Decoder

Returns:

Returns true if another array value is available.

getCurrentKey

protected abstract String getCurrentKey()
                                 throws IOException

Get the current object field name. Only called for AbstractStreamDecoder.TokenType.KEY.

Returns:

The current field key

Throws:

IOException - if an unrecoverable error occurs

decodeKey

@Nullable
public String decodeKey()
                 throws IOException

Description copied from interface: Decoder

Decodes a key, if there are no more keys to decode returns null.

Specified by:

decodeKey in interface Decoder

Returns:

The key or null if there aren't any more keys

Throws:

IOException - If an unrecoverable error occurs

decodeArray

@NonNull
public final Decoder decodeArray(io.micronaut.core.type.Argument<?> type)
                          throws IOException

Description copied from interface: Decoder

Start decoding an array.

Specified by:

decodeArray in interface Decoder

Parameters:

type - The array type

Returns:

The array decoder

Throws:

IOException - If an unrecoverable error occurs

decodeArray0

protected AbstractStreamDecoder decodeArray0(AbstractStreamDecoder.TokenType currentToken)
                                      throws IOException

Decodes the array.

Parameters:

currentToken - The current token

Returns:

The decoder

Throws:

IOException - The exception

decodeObject

@NonNull
public final Decoder decodeObject(io.micronaut.core.type.Argument<?> type)
                           throws IOException

Description copied from interface: Decoder

Decodes an object.

Specified by:

decodeObject in interface Decoder

Parameters:

type - The type, never null

Returns:

The object decoder

Throws:

IOException - If an unrecoverable error occurs

decodeObject0

protected AbstractStreamDecoder decodeObject0(AbstractStreamDecoder.TokenType currentToken)
                                       throws IOException

Decodes the object.

Parameters:

currentToken - The current token

Returns:

The decoder

Throws:

IOException - The exception

coerceScalarToString

protected abstract String coerceScalarToString(AbstractStreamDecoder.TokenType currentToken)
                                        throws IOException

Decode any non-null scalar value (number, string or boolean) to its string representation.

Parameters:

currentToken - The current token

Returns:

The current value, coerced to a string

Throws:

IOException - if an unrecoverable error occurs

decodeString

@NonNull
public String decodeString()
                    throws IOException

Description copied from interface: Decoder

Decodes a string.

Specified by:

decodeString in interface Decoder

Returns:

The string, never null

Throws:

IOException - If an unrecoverable error occurs

getString

protected abstract String getString()
                             throws IOException

Decode the current AbstractStreamDecoder.TokenType.STRING value. Called for no other token type.

Returns:

The String value

Throws:

IOException - if an unrecoverable error occurs

getBoolean

protected abstract boolean getBoolean()
                               throws IOException

Decode the current AbstractStreamDecoder.TokenType.BOOLEAN value. Called for no other token type.

Returns:

The boolean value

Throws:

IOException - if an unrecoverable error occurs

decodeBoolean

public final boolean decodeBoolean()
                            throws IOException

Description copied from interface: Decoder

Decodes a boolean.

Specified by:

decodeBoolean in interface Decoder

Returns:

The boolean

Throws:

IOException - If an unrecoverable error occurs

decodeByte

public final byte decodeByte()
                      throws IOException

Description copied from interface: Decoder

Decodes a byte.

Specified by:

decodeByte in interface Decoder

Returns:

The byte

Throws:

IOException - If an unrecoverable error occurs

decodeShort

public final short decodeShort()
                        throws IOException

Description copied from interface: Decoder

Decodes a short.

Specified by:

decodeShort in interface Decoder

Returns:

The short

Throws:

IOException - If an unrecoverable error occurs

decodeChar

public final char decodeChar()
                      throws IOException

Description copied from interface: Decoder

Decodes a char.

Specified by:

decodeChar in interface Decoder

Returns:

The char

Throws:

IOException - If an unrecoverable error occurs

decodeInt

public final int decodeInt()
                    throws IOException

Description copied from interface: Decoder

Decodes a int.

Specified by:

decodeInt in interface Decoder

Returns:

The int

Throws:

IOException - If an unrecoverable error occurs

decodeLong

public final long decodeLong()
                      throws IOException

Description copied from interface: Decoder

Decodes a long.

Specified by:

decodeLong in interface Decoder

Returns:

The long

Throws:

IOException - If an unrecoverable error occurs

getLong

protected abstract long getLong()
                         throws IOException

Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a long value. Called for no other token type.

Returns:

The number value

Throws:

IOException - if an unrecoverable error occurs

getInteger

protected int getInteger()
                  throws IOException

Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a long value. Called for no other token type.

Returns:

The number value

Throws:

IOException - if an unrecoverable error occurs

getDouble

protected abstract double getDouble()
                             throws IOException

Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a double value. Called for no other token type.

Returns:

The number value

Throws:

IOException - if an unrecoverable error occurs

getBigInteger

protected abstract BigInteger getBigInteger()
                                     throws IOException

Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a BigInteger value. Called for no other token type.

Returns:

The number value

Throws:

IOException - if an unrecoverable error occurs

getBigDecimal

protected abstract BigDecimal getBigDecimal()
                                     throws IOException

Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a BigDecimal value. Called for no other token type.

Returns:

The number value

Throws:

IOException - if an unrecoverable error occurs

getBestNumber

protected abstract Number getBestNumber()
                                 throws IOException

Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a Number value. Called for no other token type.

Returns:

The number value

Throws:

IOException - if an unrecoverable error occurs

getBestNumberNode

protected io.micronaut.json.tree.JsonNode getBestNumberNode()
                                                     throws IOException

Decode the current AbstractStreamDecoder.TokenType.NUMBER value as a numeric JsonNode. Called for no other token type. Default implementation tries to construct a node from getBestNumber().

Returns:

The number value

Throws:

IOException - if an unrecoverable error occurs

decodeFloat

public final float decodeFloat()
                        throws IOException

Description copied from interface: Decoder

Decodes a float.

Specified by:

decodeFloat in interface Decoder

Returns:

The float

Throws:

IOException - If an unrecoverable error occurs

decodeDouble

public final double decodeDouble()
                          throws IOException

Description copied from interface: Decoder

Decodes a double.

Specified by:

decodeDouble in interface Decoder

Returns:

The double

Throws:

IOException - If an unrecoverable error occurs

decodeBigInteger

@NonNull
public final BigInteger decodeBigInteger()
                                  throws IOException

Description copied from interface: Decoder

Decodes a BigInteger.

Specified by:

decodeBigInteger in interface Decoder

Returns:

The BigInteger, never null

Throws:

IOException - If an unrecoverable error occurs

decodeBigDecimal

@NonNull
public final BigDecimal decodeBigDecimal()
                                  throws IOException

Description copied from interface: Decoder

Decodes a BigDecimal.

Specified by:

decodeBigDecimal in interface Decoder

Returns:

The BigDecimal, never null

Throws:

IOException - If an unrecoverable error occurs

decodeNumber

protected final <T> T decodeNumber(AbstractStreamDecoder.TokenType currentToken,
 AbstractStreamDecoder.ValueDecoder<T> fromNumberToken,
 Function<String,T> fromString,
 T zero,
 T one)
                            throws IOException

Decode a number type, applying all necessary coercions.

Type Parameters:

T - The number type.

Parameters:

currentToken - The current token

fromNumberToken - Called if currentToken() is a AbstractStreamDecoder.TokenType.NUMBER.

fromString - Called for the textual value if currentToken() is a AbstractStreamDecoder.TokenType.STRING. Should throw NumberFormatException on parse failure.

zero - The zero value.

one - The one value.

Returns:

The parsed number.

Throws:

IOException - if an unrecoverable error occurs

decodeCustom

protected final <T> T decodeCustom(AbstractStreamDecoder.ValueDecoder<T> readFunction)
                            throws IOException

Decode a custom type.

Type Parameters:

T - Value type

Parameters:

readFunction - Function to call for reading the value. The AbstractStreamDecoder parameter to the function will just be this, but this allows subclasses to avoid capturing this to avoid an allocation.

Returns:

The parsed value.

Throws:

IOException - if an unrecoverable error occurs

decodeCustom

protected final <T> T decodeCustom(AbstractStreamDecoder.ValueDecoder<T> readFunction,
 boolean callNext)
                            throws IOException

Decode a custom type.

Type Parameters:

T - Value type

Parameters:

readFunction - Function to call for reading the value. The AbstractStreamDecoder parameter to the function will just be this, but this allows subclasses to avoid capturing this to avoid an allocation.

callNext - Pass "true" if next token should be read after invocation

Returns:

The parsed value.

Throws:

IOException - if an unrecoverable error occurs

decodeNull

public final boolean decodeNull()
                         throws IOException

Description copied from interface: Decoder

Attempt to decode a null value. Returns false if this value is not null, and another method should be used for decoding. Returns true if this value was null, and the cursor has been advanced to the next value.

Specified by:

decodeNull in interface Decoder

Returns:

Returns true if the value was null

Throws:

IOException - If an unrecoverable error occurs

decodeBuffer

public Decoder decodeBuffer()
                     throws IOException

Description copied from interface: Decoder

Buffer the whole subtree of this value and return it as a new Decoder. The returned Decoder can be used independently to this Decoder. This means actual parsing of the subtree can be delayed.

The returned Decoder should behave identically to this Decoder. This means that for example decoder.decodeDouble() should be equivalent to decoder.decodeBuffer().decodeDouble().

Specified by:

decodeBuffer in interface Decoder

Returns:

An independent decoder that visits this subtree.

Throws:

IOException - If an unrecoverable error occurs

decodeNode

@NonNull
public io.micronaut.json.tree.JsonNode decodeNode()
                                           throws IOException

Description copied from interface: Decoder

Decodes the current state into a JsonNode.

Specified by:

decodeNode in interface Decoder

Returns:

The decoded node

Throws:

IOException - If an unrecoverable error occurs

decodeArbitrary

@Nullable
public final Object decodeArbitrary()
                             throws IOException

Description copied from interface: Decoder

Decodes the current state into an arbitrary object.

The following should be decoded by this method:

• Object types will be decoded into a Map
• Array types will be decoded into a List
• JSON primitive types into the equivalent Java wrapper type

Specified by:

decodeArbitrary in interface Decoder

Returns:

The decoded object

Throws:

IOException - If an unrecoverable error occurs

skipChildren

protected abstract void skipChildren()
                              throws IOException

If we are at a AbstractStreamDecoder.TokenType.START_OBJECT or AbstractStreamDecoder.TokenType.START_ARRAY, skip to the matching AbstractStreamDecoder.TokenType.END_OBJECT or AbstractStreamDecoder.TokenType.END_ARRAY. Else, do nothing.

Throws:

IOException - if an unrecoverable error occurs

skipValue

public final void skipValue()
                     throws IOException

Description copied from interface: Decoder

Skips the current value.

Specified by:

skipValue in interface Decoder

Throws:

IOException - If an unrecoverable error occurs