com.esotericsoftware.yamlbeans

Class YamlReader

java.lang.Object

com.esotericsoftware.yamlbeans.YamlReader

All Implemented Interfaces:

AutoCloseable

public class YamlReader
extends Object
implements AutoCloseable

Deserializes Java objects from YAML.

Author:

Nathan Sweet

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	YamlReader.YamlReaderException

Constructor Summary

Constructors

Constructor and Description
YamlReader(Reader reader)
YamlReader(Reader reader, YamlConfig config)
YamlReader(String yaml)
YamlReader(String yaml, YamlConfig config)

Method Summary

Modifier and Type	Method and Description
void	close()
protected Object	createObject(Class type) Returns a new object of the requested type.
protected Class<?>	findTagClass(String tag, ClassLoader classLoader) Used during reading when a tag is present, and YamlConfig.setClassTag(String, Class) was not used for that tag.
Object	get(String alias) Return the object with the given alias, or null.
YamlConfig	getConfig()
static void	main(String[] args)
Object	read() Reads the next YAML document and deserializes it into an object.
<T> T	read(Class<T> type) Reads an object of the specified type from YAML.
<T> T	read(Class<T> type, Class elementType) Reads an array, Map, List, or Collection object of the specified type from YAML, using the specified element type.
<T> Iterator<T>	readAll(Class<T> type) Returns an iterator that reads all documents from YAML into objects.
protected Object	readValue(Class type, Class elementType, Class defaultType) Reads an object from the YAML.

Methods inherited from class java.lang.Object

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

Constructor Detail

YamlReader

public YamlReader(Reader reader)

YamlReader

public YamlReader(Reader reader,
                  YamlConfig config)

YamlReader

public YamlReader(String yaml)

YamlReader

public YamlReader(String yaml,
                  YamlConfig config)

Method Detail

getConfig

public YamlConfig getConfig()

get

public Object get(String alias)

Return the object with the given alias, or null. This is only valid after objects have been read and before close()

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Throws:

IOException

read

public Object read()
            throws YamlException

Reads the next YAML document and deserializes it into an object. The type of object is defined by the YAML tag. If there is no YAML tag, the object will be an ArrayList, HashMap, or String.

This method creates and configures an instance of a class specified by the YAML data, so should be used only with YAML data from a trusted source.

Throws:

YamlException

read

public <T> T read(Class<T> type)
           throws YamlException

Reads an object of the specified type from YAML.

Parameters:

type - The type of object to read. If null, behaves the same as {read().

Throws:

YamlReader.YamlReaderException - if the YAML data specifies a type that is incompatible with the specified type.

YamlException

read

public <T> T read(Class<T> type,
                  Class elementType)
           throws YamlException

Reads an array, Map, List, or Collection object of the specified type from YAML, using the specified element type.

Parameters:

type - The type of object to read. If null, behaves the same as {read().

Throws:

YamlReader.YamlReaderException - if the YAML data specifies a type that is incompatible with the specified type.

YamlException

readAll

public <T> Iterator<T> readAll(Class<T> type)

Returns an iterator that reads all documents from YAML into objects.

Parameters:

type - The type of object to read. If null, behaves the same as {read().

readValue

protected Object readValue(Class type,
                           Class elementType,
                           Class defaultType)
                    throws YamlException,
                           Parser.ParserException,
                           Tokenizer.TokenizerException

Reads an object from the YAML. Can be overidden to take some action for any of the objects returned.

Parameters:

type - May be null.

Throws:

YamlReader.YamlReaderException - if the YAML data specifies a type that is incompatible with the specified type.

YamlException

Parser.ParserException

Tokenizer.TokenizerException

findTagClass

protected Class<?> findTagClass(String tag,
                                ClassLoader classLoader)
                         throws ClassNotFoundException

Used during reading when a tag is present, and YamlConfig.setClassTag(String, Class) was not used for that tag. Attempts to load the class corresponding to that tag.

If this returns a non-null Class, that will be used as the deserialization type regardless of whether a type was explicitly asked for or if a default type exists.

If this returns null, no guidance will be provided by the tag and we will fall back to the default type or a requested target type, if any exist.

If this throws a ClassNotFoundException, parsing will fail.

The default implementation is simply Class.forName(tag, true, classLoader); and never returns null.

You can override this to handle cases where you do not want to respect the type tags found in a document, eg if they were output by another program using classes that do not exist on your classpath.

Throws:

ClassNotFoundException

createObject

protected Object createObject(Class type)
                       throws InvocationTargetException

Returns a new object of the requested type.

Throws:

InvocationTargetException

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception