org.apache.brooklyn.util.javalang.coerce

Class TypeCoercerExtensible

java.lang.Object

org.apache.brooklyn.util.javalang.coerce.TypeCoercerExtensible

All Implemented Interfaces:

TypeCoercer

public class TypeCoercerExtensible
extends java.lang.Object
implements TypeCoercer

Attempts to coerce value to targetType.

Maintains a registry of adapter functions for type pairs in a Table which is searched after checking various strategies, including the following:

• value.asTargetType()
• TargetType.fromType(value) (if value instanceof Type)
• value.targetTypeValue() (handy for primitives)
• TargetType.valueOf(value) (for enums)

A default set of adapters will handle most common Java-type coercions as well as String coercion to:

• Set, List, Map and similar -- parses as YAML
• Date -- parses using Time.parseDate(String)
• Duration -- parses using Duration.parse(String)

Method Summary

Modifier and Type	Method and Description
<T> T	coerce(java.lang.Object value, java.lang.Class<T> targetType)
<T> T	coerce(java.lang.Object value, com.google.common.reflect.TypeToken<T> targetTypeToken)
<T> com.google.common.base.Function<java.lang.Object,T>	function(java.lang.Class<T> type) Returns a function that does a type coercion to the given type.
static TypeCoercerExtensible	newDefault() has all the strategies (primitives, collections, etc) and all the adapters from CommonAdaptorTypeCoercions
static TypeCoercerExtensible	newEmpty() has all the strategies (primitives, collections, etc) but no adapters, so caller can pick and choose e.g.
<A,B> com.google.common.base.Function<? super A,B>	registerAdapter(java.lang.Class<A> sourceType, java.lang.Class<B> targetType, com.google.common.base.Function<? super A,B> fn) Registers an adapter for use with type coercion.
<T> Maybe<T>	tryCoerce(java.lang.Object input, java.lang.Class<T> type)
<T> Maybe<T>	tryCoerce(java.lang.Object value, com.google.common.reflect.TypeToken<T> targetTypeToken)

Methods inherited from class java.lang.Object

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

Method Detail

newDefault

public static TypeCoercerExtensible newDefault()

has all the strategies (primitives, collections, etc) and all the adapters from CommonAdaptorTypeCoercions

newEmpty

public static TypeCoercerExtensible newEmpty()

has all the strategies (primitives, collections, etc) but no adapters, so caller can pick and choose e.g. from CommonAdaptorTypeCoercions

coerce

public <T> T coerce(java.lang.Object value,
                    java.lang.Class<T> targetType)

Specified by:

coerce in interface TypeCoercer

coerce

public <T> T coerce(java.lang.Object value,
                    com.google.common.reflect.TypeToken<T> targetTypeToken)

tryCoerce

public <T> Maybe<T> tryCoerce(java.lang.Object input,
                              java.lang.Class<T> type)

Specified by:

tryCoerce in interface TypeCoercer

tryCoerce

public <T> Maybe<T> tryCoerce(java.lang.Object value,
                              com.google.common.reflect.TypeToken<T> targetTypeToken)

Specified by:

tryCoerce in interface TypeCoercer

function

public <T> com.google.common.base.Function<java.lang.Object,T> function(java.lang.Class<T> type)

Returns a function that does a type coercion to the given type. For example, TypeCoercions.function(Double.class) will return a function that will coerce its input value to a Double (or throw a ClassCoercionException if that is not possible).

registerAdapter

public <A,B> com.google.common.base.Function<? super A,B> registerAdapter(java.lang.Class<A> sourceType,
                                                                          java.lang.Class<B> targetType,
                                                                          com.google.common.base.Function<? super A,B> fn)

Registers an adapter for use with type coercion. Returns any old adapter registered for this pair.