Class ClassUtils

src/main/java/org/apache/commons/lang3/ClassUtils.java:51–1750

Operates on classes without using reflection. This class handles invalid null inputs as best it can. Each method documents its behavior in more detail. The notion of a canonical name includes the human-readable name for the type, for example int[]. The non-cano

 * @since 2.0
 */
public class ClassUtils {

    /**
     * Enumerates inclusivity literals for {@link #hierarchy(Class, Interfaces)}.
     *
     * @since 3.2
     */
    public enum Interfaces {

        /** Includes interfaces. */
        INCLUDE,

        /** Excludes interfaces. */
        EXCLUDE
    }

    /**
     * The JLS-specified maximum class name length {@value}.
     *
     * @see Class#forName(String, boolean, ClassLoader)
     * @see <a href="https://docs.oracle.com/javase/specs/jvms/se25/html/jvms-4.html#jvms-4.4.1">JVM: Array dimension limits in JVM Specification CONSTANT_Class_info</a>
     * @see <a href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-6.html#jls-6.7">JLS: Fully Qualified Names and Canonical Names</a>
     * @see <a href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-13.html#jls-13.1">JLS: The Form of a Binary</a>
     */
    private static final int MAX_CLASS_NAME_LENGTH = 65535;

    /**
     * The JVM-specified {@code CONSTANT_Class_info} structure defines an array type descriptor is valid only if it represents {@value} or fewer dimensions.
     *
     * @see Class#forName(String, boolean, ClassLoader)
     * @see <a href="https://docs.oracle.com/javase/specs/jvms/se25/html/jvms-4.html#jvms-4.4.1">JVM: Array dimension limits in JVM Specification CONSTANT_Class_info</a>
     * @see <a href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-6.html#jls-6.7">JLS: Fully Qualified Names and Canonical Names</a>
     * @see <a href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-13.html#jls-13.1">JLS: The Form of a Binary</a>
     */
    private static final int MAX_JVM_ARRAY_DIMENSION = 255;

    /**
     * The maximum number of array dimensions.
     */
    private static final int MAX_DIMENSIONS = 255;

    private static final Comparator<Class<?>> COMPARATOR = (o1, o2) -> Objects.compare(getName(o1), getName(o2), String::compareTo);

    /**
     * The package separator character: {@code '&#x2e;' == {@value}}.
     */
    public static final char PACKAGE_SEPARATOR_CHAR = '.';

    /**
     * The package separator String: {@code "&#x2e;"}.
     */
    public static final String PACKAGE_SEPARATOR = String.valueOf(PACKAGE_SEPARATOR_CHAR);

    /**
     * The inner class separator character: {@code '$' == {@value}}.
     */
    public static final char INNER_CLASS_SEPARATOR_CHAR = '$';