Package com.helger.commons.lang

Class ClassHelper

java.lang.Object
com.helger.commons.lang.ClassHelper
@Immutable public final class ClassHelper extends Object
Class helper methods.
Author:
Philip Helger

  • Method Details

    • isPublicClass

      public static boolean isPublicClass(@Nullable Class<?> aClass)

    • isInstancableClass

      public static boolean isInstancableClass(@Nullable Class<?> aClass)
      Check if the passed class is public, instancable and has a no-argument constructor.
      Parameters:
      aClass - The class to check. May be null.
      Returns:
      true if the class is public, instancable and has a no-argument constructor that is public.

    • isPublic

      public static boolean isPublic(@Nullable Class<?> aClass)

    • isInterface

      public static boolean isInterface(@Nullable Class<?> aClass)
      Check if the passed class is an interface or not. Please note that annotations are also interfaces!
      Parameters:
      aClass - The class to check.
      Returns:
      true if the class is an interface (or an annotation)

    • isAnnotationClass

      public static boolean isAnnotationClass(@Nullable Class<?> aClass)

    • isEnumClass

      public static boolean isEnumClass(@Nullable Class<?> aClass)

    • isAbstractClass

      public static boolean isAbstractClass(@Nullable Class<?> aClass)
      Check if the passed class is abstract or not. Note: interfaces and annotations are also considered as abstract whereas arrays are never abstract.
      Parameters:
      aClass - The class to check.
      Returns:
      true if the passed class is abstract

    • isArrayClass

      public static boolean isArrayClass(@Nullable Class<?> aClass)

    • isPrimitiveType

      public static boolean isPrimitiveType(@Nullable Class<?> aClass)

    • isPrimitiveWrapperType

      public static boolean isPrimitiveWrapperType(@Nullable Class<?> aClass)

    • getPrimitiveWrapperClass

      @Nullable public static Class<?> getPrimitiveWrapperClass(@Nullable Class<?> aClass)
      Get the primitive wrapper class of the passed primitive class.
      Parameters:
      aClass - The primitive class. May be null.
      Returns:
      null if the passed class is not a primitive class.

    • getPrimitiveClass

      @Nullable public static Class<?> getPrimitiveClass(@Nullable Class<?> aClass)
      Get the primitive class of the passed primitive wrapper class.
      Parameters:
      aClass - The primitive wrapper class. May be null.
      Returns:
      null if the passed class is not a primitive wrapper class.

    • getAllPrimitiveClasses

      @Nonnull @ReturnsMutableCopy public static ICommonsSet<Class<?>> getAllPrimitiveClasses()

    • getAllPrimitiveWrapperClasses

      @Nonnull @ReturnsMutableCopy public static ICommonsSet<Class<?>> getAllPrimitiveWrapperClasses()

    • isStringClass

      public static boolean isStringClass(@Nullable Class<?> aClass)

    • isCharacterClass

      public static boolean isCharacterClass(@Nullable Class<?> aClass)

    • isBooleanClass

      public static boolean isBooleanClass(@Nullable Class<?> aClass)

    • isFloatingPointClass

      public static boolean isFloatingPointClass(@Nullable Class<?> aClass)

    • isIntegerClass

      public static boolean isIntegerClass(@Nullable Class<?> aClass)

    • areConvertibleClasses

      public static boolean areConvertibleClasses(@Nonnull Class<?> aSrcClass, @Nonnull Class<?> aDstClass)
      Check if the passed classes are convertible. Includes conversion checks between primitive types and primitive wrapper types.
      Parameters:
      aSrcClass - First class. May not be null.
      aDstClass - Second class. May not be null.
      Returns:
      true if the classes are directly convertible.

    • getClass

      @Nullable public static Class<?> getClass(@Nullable Object aObject)
      null-safe helper method to determine the class of an object.
      Parameters:
      aObject - The object to query. May be null.
      Returns:
      null if the passed object is null.

    • getClassName

      @Nullable public static String getClassName(@Nullable Object aObject)
      null-safe helper method to determine the class name of an object.
      Parameters:
      aObject - The object to query. May be null.
      Returns:
      null if the passed object is null.

    • getClassLocalName

      @Nullable public static String getClassLocalName(@Nullable Object aObject)
      Get the name of the object's class without the package.
      Parameters:
      aObject - The object to get the information from. May be null .
      Returns:
      The local name of the passed object's class.

    • getClassLocalName

      @Nullable public static String getClassLocalName(@Nullable Class<?> aClass)
      Get the name of the class without the package.
      Parameters:
      aClass - The class to get the information from. May be null.
      Returns:
      The local name of the passed class.

    • getClassLocalName

      @Nullable public static String getClassLocalName(@Nullable String sClassName)
      Get the name of the class without the package.
      Parameters:
      sClassName - The fully qualified name of the class. May be null.
      Returns:
      The local name of the passed class. Never null.

    • getClassPackageName

      @Nullable public static String getClassPackageName(@Nullable Object aObject)
      Get the name of the package the passed object resides in.
      Parameters:
      aObject - The class to get the information from. May be null.
      Returns:
      The package name of the passed object.

    • getClassPackageName

      @Nullable public static String getClassPackageName(@Nullable Class<?> aClass)
      Get the name of the package the passed class resides in.
      Parameters:
      aClass - The class to get the information from. May not be null.
      Returns:
      The package name of the passed class.

    • getClassPackageName

      @Nullable public static String getClassPackageName(@Nullable String sClassName)
      Get the name of the package the passed class resides in.
      Parameters:
      sClassName - The name class to get the information from. May be null .
      Returns:
      The package name of the passed class.

    • getSafeClassName

      @Nonnull @Nonempty public static String getSafeClassName(@Nullable Object aObject)
      Get the class name of the passed object. If the object itself is of type Class, its name is retrieved, other Object.getClass() is called.
      Parameters:
      aObject - The object who's class name is to be retrieved.
      Returns:
      "null" for a null parameter

    • getDirectoryFromPackage

      @Nullable public static String getDirectoryFromPackage(@Nullable Package aPackage)
      Convert a package name to a relative directory name.
      Parameters:
      aPackage - The package to be converted. May be null.
      Returns:
      The directory name using forward slashes (/) instead of the dots.

    • getDirectoryFromPackage

      @Nullable public static String getDirectoryFromPackage(@Nullable String sPackage)
      Convert a package name to a relative directory name.
      Parameters:
      sPackage - The name of the package to be converted. May be null.
      Returns:
      The directory name using forward slashes (/) instead of the dots.

    • getPathFromClass

      @Nullable public static String getPathFromClass(@Nullable Class<?> aClass)
      Get the path representation of the passed class. The path representation is achieved by replacing all dots (.) with forward slashes (/) in the class name.
      Parameters:
      aClass - The class of which the path is to be retrieved. May be null.
      Returns:
      The path representation. Never null.

    • getPathFromClass

      @Nullable public static String getPathFromClass(@Nullable String sClassName)
      Get the path representation of the passed class name. The path representation is achieved by replacing all dots (.) with forward slashes (/) in the class name.
      Parameters:
      sClassName - The class name of which the path is to be retrieved. May be null.
      Returns:
      The path representation

    • getClassFromPath

      @Nullable public static String getClassFromPath(@Nullable String sPath)
      Get the class name of the passed path. The class name is retrieved by replacing all path separators (\ and /) with dots (.). This method does not handle the file extension, so it's up to the caller to skip of any file extension!
      Parameters:
      sPath - The path to be converted. May be null.
      Returns:
      The class name.

    • getObjectAddress

      @Nonnull @Nonempty public static String getObjectAddress(@Nullable Object aObject)
      Get the hex representation of the passed object's address. Note that this method makes no differentiation between 32 and 64 bit architectures. The result is always a hexadecimal value preceded by "0x" and followed by exactly 8 characters.
      Parameters:
      aObject - The object who's address is to be retrieved. May be null.
      Returns:
      Depending on the current architecture. Always starting with "0x" and than containing the address.
      See Also:

    • getResource

      @Nullable public static URL getResource(@Nonnull Class<?> aClass, @Nonnull @Nonempty String sPath)
      Get the URL of the passed resource using the class loader of the specified class only. This is a sanity wrapper around class.getResource (sPath).
      Parameters:
      aClass - The class to be used. May not be null.
      sPath - The path to be resolved. May neither be null nor empty. Internally it is ensured that the provided path does start with a slash.
      Returns:
      null if the path could not be resolved using the specified class loader.

    • getResourceAsStream

      @Nullable public static InputStream getResourceAsStream(@Nonnull Class<?> aClass, @Nonnull @Nonempty String sPath)
      Get the input stream of the passed resource using the class loader of the specified class only. This is a sanity wrapper around class.getResourceAsStream (sPath).
      Parameters:
      aClass - The class to be used. May not be null.
      sPath - The path to be resolved. May neither be null nor empty. Internally it is ensured that the provided path does start with a slash.
      Returns:
      null if the path could not be resolved using the specified class loader.