org.apache.juneau

Class BeanTraverseContext

java.lang.Object

org.apache.juneau.Context

org.apache.juneau.BeanContext

org.apache.juneau.BeanTraverseContext

Direct Known Subclasses:

JsonSchemaGenerator, Serializer, SerializerGroup

@ConfigurableContext
public abstract class BeanTraverseContext
extends BeanContext

Parent class for all classes that traverse POJOs.

Description

Base class that serves as the parent class for all serializers and other classes that traverse POJOs.

Field Summary

Fields

Modifier and Type	Field and Description
static String	BEANTRAVERSE_detectRecursions Configuration property: Automatically detect POJO recursions.
static String	BEANTRAVERSE_ignoreRecursions Configuration property: Ignore recursion errors.
static String	BEANTRAVERSE_initialDepth Configuration property: Initial depth.
static String	BEANTRAVERSE_maxDepth Configuration property: Max traversal depth.

Fields inherited from class org.apache.juneau.BeanContext

BEAN_beanClassVisibility, BEAN_beanConstructorVisibility, BEAN_beanDictionary, BEAN_beanDictionary_add, BEAN_beanDictionary_remove, BEAN_beanFieldVisibility, BEAN_beanFilters, BEAN_beanFilters_add, BEAN_beanFilters_remove, BEAN_beanMapPutReturnsOldValue, BEAN_beanMethodVisibility, BEAN_beansRequireDefaultConstructor, BEAN_beansRequireSerializable, BEAN_beansRequireSettersForGetters, BEAN_beansRequireSomeProperties, BEAN_beanTypePropertyName, BEAN_bpi, BEAN_bpro, BEAN_bpwo, BEAN_bpx, BEAN_debug, BEAN_examples, BEAN_excludeProperties, BEAN_fluentSetters, BEAN_ignoreInvocationExceptionsOnGetters, BEAN_ignoreInvocationExceptionsOnSetters, BEAN_ignorePropertiesWithoutSetters, BEAN_ignoreUnknownBeanProperties, BEAN_ignoreUnknownNullBeanProperties, BEAN_implClasses, BEAN_includeProperties, BEAN_locale, BEAN_mediaType, BEAN_notBeanClasses, BEAN_notBeanClasses_add, BEAN_notBeanClasses_remove, BEAN_notBeanPackages, BEAN_notBeanPackages_add, BEAN_notBeanPackages_remove, BEAN_pojoSwaps, BEAN_pojoSwaps_add, BEAN_pojoSwaps_remove, BEAN_propertyNamer, BEAN_sortProperties, BEAN_timeZone, BEAN_useEnumNames, BEAN_useInterfaceProxies, BEAN_useJavaBeanIntrospector, DEFAULT, DEFAULT_SORTED

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BeanTraverseContext(PropertyStore ps) Constructor

Method Summary

Modifier and Type	Method and Description
BeanTraverseBuilder	builder() Creates a builder from this context object.
BeanTraverseSession	createSession() Create a new bean session based on the properties defined on this context.
BeanTraverseSession	createSession(BeanSessionArgs args) Create a new bean session based on the properties defined on this context combined with the specified runtime args.
protected int	getInitialDepth() Configuration property: Initial depth.
protected int	getMaxDepth() Configuration property: Max traversal depth.
protected boolean	isDetectRecursions() Configuration property: Automatically detect POJO recursions.
protected boolean	isIgnoreRecursions() Configuration property: Ignore recursion errors.
ObjectMap	toMap() Returns the properties defined on this bean context as a simple map for debugging purposes.

Methods inherited from class org.apache.juneau.BeanContext

_class, create, createBeanSession, createBeanSession, createDefaultBeanSessionArgs, createDefaultSessionArgs, createSession, dumpCacheStats, getBeanClassVisibility, getBeanConstructorVisibility, getBeanDictionaryClasses, getBeanFieldVisibility, getBeanFilters, getBeanMeta, getBeanMethodVisibility, getBeanRegistry, getBeanTypePropertyName, getBpi, getBpi, getBpro, getBpro, getBpwo, getBpwo, getBpx, getBpx, getClassMeta, getClassMeta, getClassMetaForObject, getExamples, getImplClassConstructor, getImplClasses, getLocale, getMediaType, getNotBeanClasses, getNotBeanPackagesNames, getNotBeanPackagesPrefixes, getPojoSwaps, getPropertyNamer, getTimeZone, hasSameCache, isBean, isBeanMapPutReturnsOldValue, isBeansRequireDefaultConstructor, isBeansRequireSerializable, isBeansRequireSettersForGetters, isBeansRequireSomeProperties, isDebug, isFluentSetters, isIgnoreInvocationExceptionsOnGetters, isIgnoreInvocationExceptionsOnSetters, isIgnorePropertiesWithoutSetters, isIgnoreUnknownBeanProperties, isIgnoreUnknownNullBeanProperties, isNotABean, isSortProperties, isUseEnumNames, isUseInterfaceProxies, isUseJavaBeanIntrospector, object, resolveClassMeta, string

Methods inherited from class org.apache.juneau.Context

equals, getArrayProperty, getArrayProperty, getBooleanProperty, getCdlProperty, getClassArrayProperty, getClassArrayProperty, getClassArrayProperty, getClassListProperty, getClassListProperty, getClassMapProperty, getClassMapProperty, getClassProperty, getClassSetProperty, getClassSetProperty, getInstanceArrayProperty, getInstanceArrayProperty, getInstanceArrayProperty, getInstanceProperty, getInstanceProperty, getInstanceProperty, getIntegerProperty, getListProperty, getListProperty, getLongProperty, getMapProperty, getProperty, getProperty, getPropertyKeys, getPropertyStore, getSetProperty, getSetProperty, getStringProperty, getStringPropertyWithNone, hashCode, identityCode, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

BEANTRAVERSE_detectRecursions

public static final String BEANTRAVERSE_detectRecursions

Configuration property: Automatically detect POJO recursions.

Property:

• Name: "BeanTraverseContext.detectRecursions.b"
• Data type: Boolean
• Default: false
• Session property: false
• Methods:
  • BeanTraverseBuilder.detectRecursions(boolean)
  • BeanTraverseBuilder.detectRecursions()

Description:

Specifies that recursions should be checked for during traversal.

Recursions can occur when traversing models that aren't true trees but rather contain loops.
In general, unchecked recursions cause stack-overflow-errors.
These show up as ParseExceptions with the message "Depth too deep. Stack overflow occurred.".

The behavior when recursions are detected depends on the value for BEANTRAVERSE_ignoreRecursions.

For example, if a model contains the links A->B->C->A, then the JSON generated will look like the following when BEANTRAVERSE_ignoreRecursions is true...

{A:{B:{C:null}}}

• Checking for recursion can cause a small performance penalty.

Example:

// Create a serializer that never adds _type to nodes. WriterSerializer s = JsonSerializer .create() .detectRecursions() .ignoreRecursions() .build(); // Same, but use property. WriterSerializer s = JsonSerializer .create() .set(BEANTRAVERSE_detectRecursions, true) .set(BEANTRAVERSE_ignoreRecursions, true) .build(); // Create a POJO model with a recursive loop. public class A { public Object f; } A a = new A(); a.f = a; // Produces "{f:null}" String json = s.serialize(a);

See Also:

Constant Field Values

BEANTRAVERSE_ignoreRecursions

public static final String BEANTRAVERSE_ignoreRecursions

Configuration property: Ignore recursion errors.

Property:

• Name: "BeanTraverseContext.ignoreRecursions.b"
• Data type: Boolean
• Default: false
• Session property: false
• Methods:
  • BeanTraverseBuilder.ignoreRecursions(boolean)
  • BeanTraverseBuilder.ignoreRecursions()

Description:

Used in conjunction with BEANTRAVERSE_detectRecursions.
Setting is ignored if BEANTRAVERSE_detectRecursions is false.

If true, when we encounter the same object when traversing a tree, we set the value to null.
Otherwise, a BeanRecursionException is thrown with the message "Recursion occurred, stack=...".

See Also:

Constant Field Values

BEANTRAVERSE_initialDepth

public static final String BEANTRAVERSE_initialDepth

Configuration property: Initial depth.

Property:

• Name: "BeanTraverseContext.initialDepth.i"
• Data type: Integer
• Default: 0
• Session property: false
• Methods:
  • BeanTraverseBuilder.initialDepth(int)

Description:

The initial indentation level at the root.
Useful when constructing document fragments that need to be indented at a certain level.

Example:

// Create a serializer with whitespace enabled and an initial depth of 2. WriterSerializer s = JsonSerializer .create() .ws() .initialDepth(2) .build(); // Same, but use property. WriterSerializer s = JsonSerializer .create() .set(BEANTRAVERSE_useWhitespace, true) .set(BEANTRAVERSE_initialDepth, 2) .build(); // Produces "\t\t{\n\t\t\t'foo':'bar'\n\t\t}\n" String json = s.serialize(new MyBean());

See Also:

Constant Field Values

BEANTRAVERSE_maxDepth

public static final String BEANTRAVERSE_maxDepth

Configuration property: Max traversal depth.

Property:

• Name: "BeanTraverseContext.maxDepth.i"
• Data type: Integer
• Default: 100
• Session property: false
• Methods:
  • BeanTraverseBuilder.maxDepth(int)

Description:

Abort traversal if specified depth is reached in the POJO tree.
If this depth is exceeded, an exception is thrown.

Example:

// Create a serializer that throws an exception if the depth is greater than 20. WriterSerializer s = JsonSerializer .create() .maxDepth(20) .build(); // Same, but use property. WriterSerializer s = JsonSerializer .create() .set(BEANTRAVERSE_maxDepth, 20) .build();

See Also:

Constant Field Values

Constructor Detail

BeanTraverseContext

protected BeanTraverseContext(PropertyStore ps)

Constructor

Parameters:

ps - The property store containing all the settings for this object.

Method Detail

builder

public BeanTraverseBuilder builder()

Description copied from class: Context

Creates a builder from this context object.

Builders are used to define new contexts (e.g. serializers, parsers) based on existing configurations.

Overrides:

builder in class BeanContext

Returns:

A new ContextBuilder object.

createSession

public BeanTraverseSession createSession()

Description copied from class: BeanContext

Create a new bean session based on the properties defined on this context.

Use this method for creating sessions if you don't need to override any properties or locale/timezone currently set on this context.

Overrides:

createSession in class BeanContext

Returns:

A new session object.

createSession

public BeanTraverseSession createSession(BeanSessionArgs args)

Description copied from class: BeanContext

Create a new bean session based on the properties defined on this context combined with the specified runtime args.

Use this method for creating sessions if you don't need to override any properties or locale/timezone currently set on this context.

Overrides:

createSession in class BeanContext

Parameters:

args - The session arguments.

Returns:

A new session object.

isDetectRecursions

protected final boolean isDetectRecursions()

Configuration property: Automatically detect POJO recursions.

Returns:

true if recursions should be checked for during traversal.

See Also:

BEANTRAVERSE_detectRecursions

isIgnoreRecursions

protected final boolean isIgnoreRecursions()

Configuration property: Ignore recursion errors.

Returns:

true if when we encounter the same object when traversing a tree, we set the value to null.
Otherwise, an exception is thrown with the message "Recursion occurred, stack=...".

See Also:

BEANTRAVERSE_ignoreRecursions

getInitialDepth

protected final int getInitialDepth()

Configuration property: Initial depth.

Returns:

The initial indentation level at the root.

See Also:

BEANTRAVERSE_initialDepth

getMaxDepth

protected final int getMaxDepth()

Configuration property: Max traversal depth.

Returns:

The depth at which traversal is aborted if depth is reached in the POJO tree.
If this depth is exceeded, an exception is thrown.

See Also:

BEANTRAVERSE_maxDepth

toMap

public ObjectMap toMap()

Description copied from class: Context

Returns the properties defined on this bean context as a simple map for debugging purposes.

Overrides:

toMap in class BeanContext

Returns:

A new map containing the properties defined on this context.