Package org.apache.camel.util

Class ObjectHelper

java.lang.Object
org.apache.camel.util.ObjectHelper
public final class ObjectHelper extends Object
A number of useful helper methods for working with Objects

  • Method Details

    • equal

      public static boolean equal(Object a, Object b)
      A helper method for comparing objects for equality while handling nulls

    • equalIgnoreCase

      public static boolean equalIgnoreCase(Object a, Object b)
      A helper method for comparing objects for equality while handling case insensitivity

    • equal

      public static boolean equal(Object a, Object b, boolean ignoreCase)
      A helper method for comparing objects for equality while handling nulls

    • equalByteArray

      public static boolean equalByteArray(byte[] a, byte[] b)
      A helper method for comparing byte arrays for equality while handling nulls

    • isEqualToAny

      public static boolean isEqualToAny(Object object, Object... values)
      Returns true if the given object is equal to any of the expected value

    • toBoolean

      public static Boolean toBoolean(Object value)

    • notNull

      public static <T> T notNull(T value, String name)
      Asserts whether the value is not null
      Parameters:
      value - the value to test
      name - the key that resolved the value
      Returns:
      the passed value as is
      Throws:
      IllegalArgumentException - is thrown if assertion fails

    • notNullOrEmpty

      public static String notNullOrEmpty(String value, String name)
      Asserts that the given value is neither null nor an emptyString.
      Parameters:
      value - the value to test
      name - the key that resolved the value
      Returns:
      the passed value as is
      Throws:
      IllegalArgumentException - is thrown if assertion fails

    • notNull

      public static <T> T notNull(T value, String name, Object on)
      Asserts whether the value is not null
      Parameters:
      value - the value to test
      on - additional description to indicate where this problem occurred (appended as toString())
      name - the key that resolved the value
      Returns:
      the passed value as is
      Throws:
      IllegalArgumentException - is thrown if assertion fails

    • isEmpty

      public static boolean isEmpty(String value)
      Tests whether the value is null or an empty string or an empty collection/map.
      Parameters:
      value - the value, if its a String it will be tested for text length as well
      Returns:
      true if empty

    • isEmpty

      public static boolean isEmpty(Collection<?> value)
      Tests whether the value is null or an an empty collection
      Parameters:
      value - the value to test
      Returns:
      true if empty

    • isEmpty

      public static boolean isEmpty(Map<?,?> value)
      Tests whether the value is null or an an empty map
      Parameters:
      value - the value to test
      Returns:
      true if empty

    • isEmpty

      public static <T> boolean isEmpty(T value)
      Tests whether the value is null, an empty string or an empty collection/map.
      Parameters:
      value - the value, if its a String it will be tested for text length as well
      Returns:
      true if empty

    • isNotEmpty

      public static <T> boolean isNotEmpty(T value)
      Tests whether the value is not null, an empty string or an empty collection/map.
      Parameters:
      value - the value, if its a String it will be tested for text length as well
      Returns:
      true if not empty

    • isNotEmpty

      public static boolean isNotEmpty(String value)
      Tests whether the value is not null or an empty string
      Parameters:
      value - the value, if its a String it will be tested for text length as well
      Returns:
      true if not empty

    • isNotEmpty

      public static boolean isNotEmpty(Collection<?> value)
      Tests whether the value is null or an an empty collection
      Parameters:
      value - the value to test
      Returns:
      true if empty

    • isNotEmpty

      public static boolean isNotEmpty(Map<?,?> value)
      Tests whether the value is null or an an empty map
      Parameters:
      value - the value to test
      Returns:
      true if empty

    • firstNotNull

      public static Optional<Object> firstNotNull(Object... values)
      Returns the first non null object null.
      Parameters:
      values - the values
      Returns:
      an Optional

    • supplyIfEmpty

      public static <T> T supplyIfEmpty(T value, Supplier<T> supplier)
      Tests whether the value is null, an empty string, an empty collection or a map
      Parameters:
      value - the value, if its a String it will be tested for text length as well
      supplier - the supplier, the supplier to be used to get a value if value is null

    • ifNotEmpty

      public static <T> void ifNotEmpty(T value, Consumer<T> consumer)
      Tests whether the value is not null, an empty string, an empty collection or a map
      Parameters:
      value - the value, if its a String it will be tested for text length as well
      consumer - the consumer, the operation to be executed against value if not empty

    • matches

      public static boolean matches(List<?> list)
      Returns the predicate matching boolean on a List result set where if the first element is a boolean its value is used otherwise this method returns true if the collection is not empty
      Returns:
      true if the first element is a boolean and its value is true or if the list is non empty

    • getSystemProperty

      public static String getSystemProperty(String name, String defaultValue)
      A helper method to access a system property, catching any security exceptions
      Parameters:
      name - the name of the system property required
      defaultValue - the default value to use if the property is not available or a security exception prevents access
      Returns:
      the system property value or the default value if the property is not available or security does not allow its access

    • getSystemProperty

      public static boolean getSystemProperty(String name, Boolean defaultValue)
      A helper method to access a boolean system property, catching any security exceptions
      Parameters:
      name - the name of the system property required
      defaultValue - the default value to use if the property is not available or a security exception prevents access
      Returns:
      the boolean representation of the system property value or the default value if the property is not available or security does not allow its access

    • name

      public static String name(Class<?> type)
      Returns the type name of the given type or null if the type variable is null

    • className

      public static String className(Object value)
      Returns the type name of the given value

    • classCanonicalName

      public static String classCanonicalName(Object value)
      Returns the canonical type name of the given value

    • loadClass

      public static Class<?> loadClass(String name)
      Attempts to load the given class name using the thread context class loader or the class loader used to load this class
      Parameters:
      name - the name of the class to load
      Returns:
      the class or null if it could not be loaded

    • loadClass

      public static Class<?> loadClass(String name, ClassLoader loader)
      Attempts to load the given class name using the thread context class loader or the given class loader
      Parameters:
      name - the name of the class to load
      loader - the class loader to use after the thread context class loader
      Returns:
      the class or null if it could not be loaded

    • loadClass

      public static Class<?> loadClass(String name, ClassLoader loader, boolean needToWarn)
      Attempts to load the given class name using the thread context class loader or the given class loader
      Parameters:
      name - the name of the class to load
      loader - the class loader to use after the thread context class loader
      needToWarn - when true logs a warning when a class with the given name could not be loaded
      Returns:
      the class or null if it could not be loaded

    • loadSimpleType

      public static Class<?> loadSimpleType(String name)
      Load a simple type
      Parameters:
      name - the name of the class to load
      Returns:
      the class or null if it could not be loaded

    • loadResourceAsStream

      public static InputStream loadResourceAsStream(String name)
      Attempts to load the given resource as a stream using the thread context class loader or the class loader used to load this class
      Parameters:
      name - the name of the resource to load
      Returns:
      the stream or null if it could not be loaded

    • loadResourceAsStream

      public static InputStream loadResourceAsStream(String name, ClassLoader loader)
      Attempts to load the given resource as a stream using first the given class loader, then the thread context class loader and finally the class loader used to load this class
      Parameters:
      name - the name of the resource to load
      loader - optional classloader to attempt first
      Returns:
      the stream or null if it could not be loaded

    • loadResourceAsURL

      public static URL loadResourceAsURL(String name)
      Attempts to load the given resource as a stream using the thread context class loader or the class loader used to load this class
      Parameters:
      name - the name of the resource to load
      Returns:
      the stream or null if it could not be loaded

    • loadResourceAsURL

      public static URL loadResourceAsURL(String name, ClassLoader loader)
      Attempts to load the given resource as a stream using the thread context class loader or the class loader used to load this class
      Parameters:
      name - the name of the resource to load
      loader - optional classloader to attempt first
      Returns:
      the stream or null if it could not be loaded

    • loadResourcesAsURL

      public static Enumeration<URL> loadResourcesAsURL(String uri)
      Attempts to load the given resources from the given package name using the thread context class loader or the class loader used to load this class
      Parameters:
      uri - the name of the package to load its resources
      Returns:
      the URLs for the resources or null if it could not be loaded

    • loadResourcesAsURL

      public static Enumeration<URL> loadResourcesAsURL(String uri, ClassLoader loader)
      Attempts to load the given resources from the given package name using the thread context class loader or the class loader used to load this class
      Parameters:
      uri - the name of the package to load its resources
      loader - optional classloader to attempt first
      Returns:
      the URLs for the resources or null if it could not be loaded

    • isOverridingMethod

      public static boolean isOverridingMethod(Method source, Method target)
      Tests whether the target method overrides the source method.

      Tests whether they have the same name, return type, and parameter list.

      Parameters:
      source - the source method
      target - the target method
      Returns:
      true if it override, false otherwise

    • isOverridingMethod

      public static boolean isOverridingMethod(Method source, Method target, boolean exact)
      Tests whether the target method overrides the source method.

      Tests whether they have the same name, return type, and parameter list.

      Parameters:
      source - the source method
      target - the target method
      exact - true if the override must be exact same types, false if the types should be assignable
      Returns:
      true if it override, false otherwise

    • isOverridingMethod

      public static boolean isOverridingMethod(Class<?> inheritingClass, Method source, Method target, boolean exact)
      Tests whether the target method overrides the source method from the inheriting class.

      Tests whether they have the same name, return type, and parameter list.

      Parameters:
      inheritingClass - the class inheriting the target method overriding the source method
      source - the source method
      target - the target method
      exact - true if the override must be exact same types, false if the types should be assignable
      Returns:
      true if it override, false otherwise

    • findMethodsWithAnnotation

      public static List<Method> findMethodsWithAnnotation(Class<?> type, Class<? extends Annotation> annotationType)
      Returns a list of methods which are annotated with the given annotation
      Parameters:
      type - the type to reflect on
      annotationType - the annotation type
      Returns:
      a list of the methods found

    • findMethodsWithAnnotation

      public static List<Method> findMethodsWithAnnotation(Class<?> type, Class<? extends Annotation> annotationType, boolean checkMetaAnnotations)
      Returns a list of methods which are annotated with the given annotation
      Parameters:
      type - the type to reflect on
      annotationType - the annotation type
      checkMetaAnnotations - check for meta annotations
      Returns:
      a list of the methods found

    • hasAnnotation

      public static boolean hasAnnotation(AnnotatedElement elem, Class<? extends Annotation> annotationType, boolean checkMetaAnnotations)
      Checks if a Class or Method are annotated with the given annotation
      Parameters:
      elem - the Class or Method to reflect on
      annotationType - the annotation type
      checkMetaAnnotations - check for meta annotations
      Returns:
      true if annotations is present

    • asString

      public static String asString(Object[] objects)
      Turns the given object arrays into a meaningful string
      Parameters:
      objects - an array of objects or null
      Returns:
      a meaningful string

    • isAssignableFrom

      public static boolean isAssignableFrom(Class<?> a, Class<?> b)
      Returns true if a class is assignable from another class like the Class.isAssignableFrom(Class) method but which also includes coercion between primitive types to deal with Java 5 primitive type wrapping

    • isPrimitiveArrayType

      public static boolean isPrimitiveArrayType(Class<?> clazz)
      Returns if the given clazz type is a Java primitive array type.
      Parameters:
      clazz - the Java type to be checked
      Returns:
      true if the given type is a Java primitive array type

    • isSubclass

      public static boolean isSubclass(Class<?> clazz, Class<?> subClass)
      Checks if the given class has a subclass (extends or implements)
      Parameters:
      clazz - the class
      subClass - the subclass (class or interface)

    • arrayLength

      public static int arrayLength(Object[] pojo)
      Used by camel-bean

    • convertPrimitiveTypeToWrapperType

      public static Class<?> convertPrimitiveTypeToWrapperType(Class<?> type)
      Converts primitive types such as int to its wrapper type like Integer

    • convertWrapperTypeToPrimitiveType

      public static Class<?> convertWrapperTypeToPrimitiveType(Class<?> type)
      Converts wrapper type like Integer to its primitive type, i.e. int.

    • getDefaultCharacterSet

      public static String getDefaultCharacterSet()
      Helper method to return the default character set name

    • getPropertyName

      public static String getPropertyName(Method method)
      Returns the Java Bean property name of the given method, if it is a setter

    • hasAnnotation

      public static boolean hasAnnotation(Annotation[] annotations, Class<?> type)
      Returns true if the given collection of annotations matches the given type

    • getAnnotation

      public static <A extends Annotation> A getAnnotation(Object instance, Class<A> type)
      Gets the annotation from the given instance.
      Parameters:
      instance - the instance
      type - the annotation
      Returns:
      the annotation, or null if the instance does not have the given annotation

    • cast

      public static <T> T cast(Class<T> toType, Object value)
      Converts the given value to the required type or throw a meaningful exception

    • hasDefaultPublicNoArgConstructor

      public static boolean hasDefaultPublicNoArgConstructor(Class<?> type)
      Does the given class have a default public no-arg constructor.

    • hasDefaultNoArgConstructor

      public static boolean hasDefaultNoArgConstructor(Class<?> type)
      Does the given class have a default no-arg constructor (public or inherited).

    • type

      public static Object type(Object bean)
      Returns the type of the given object or null if the value is null

    • evaluateValuePredicate

      public static boolean evaluateValuePredicate(Object value)
      Evaluate the value as a predicate which attempts to convert the value to a boolean otherwise true is returned if the value is not null

    • createExceptionIterable

      public static Iterable<Throwable> createExceptionIterable(Throwable exception)
      Creates an Iterable to walk the exception from the bottom up (the last caused by going upwards to the root exception).
      Parameters:
      exception - the exception
      Returns:
      the Iterable
      See Also:

    • createExceptionIterator

      public static Iterator<Throwable> createExceptionIterator(Throwable exception)
      Creates an Iterator to walk the exception from the bottom up (the last caused by going upwards to the root exception).
      Parameters:
      exception - the exception
      Returns:
      the Iterator
      See Also:

    • getException

      public static <T> T getException(Class<T> type, Throwable exception)
      Retrieves the given exception type from the exception.

      Is used to get the caused exception that typically have been wrapped in some sort of Camel wrapper exception

      The strategy is to look in the exception hierarchy to find the first given cause that matches the type. Will start from the bottom (the real cause) and walk upwards.

      Parameters:
      type - the exception type wanted to retrieve
      exception - the caused exception
      Returns:
      the exception found (or null if not found in the exception hierarchy)

    • getIdentityHashCode

      public static String getIdentityHashCode(Object object)

    • lookupConstantFieldValue

      public static String lookupConstantFieldValue(Class<?> clazz, String name)
      Lookup the constant field on the given class with the given name
      Parameters:
      clazz - the class
      name - the name of the field to lookup
      Returns:
      the value of the constant field, or null if not found

    • isNaN

      public static boolean isNaN(Object value)
      Is the given value a numeric NaN type
      Parameters:
      value - the value
      Returns:
      true if its a Float.NaN or Double.NaN.

    • asList

      public static List<Object> asList(Object[] objects)
      Turns the input array to a list of objects.
      Parameters:
      objects - an array of objects or null
      Returns:
      an object list

    • addListByIndex

      public static void addListByIndex(List<Object> list, int idx, Object value)
      Adds the value to the list at the given index