Get the package name of the specified class. : Package « Reflection « Java Tutorial

import java.lang.reflect.Method;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

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public class Main {

  /** The string used to separator packages */
  public static final String PACKAGE_SEPARATOR = ".";

   * Get the package name of the specified class.
   * @param classname
   *          Class name.
   * @return Package name or "" if the classname is in the <i>default</i>
   *         package.
   * @throws EmptyStringException
   *           Classname is an empty string.
  public static String getPackageName(final String classname) {
    if (classname.length() == 0)
      System.out.println("Empty String Exception");

    int index = classname.lastIndexOf(PACKAGE_SEPARATOR);
    if (index != -1)
      return classname.substring(0, index);
    return "";

7.6.1.Demonstrate Package
7.6.2.Get full package name
7.6.3.Get package name of a class
7.6.4.getPackage() returns null for a class in the unnamed package
7.6.5.getPackage() returns null for a primitive type or array
7.6.6.Find the Package of an Object
7.6.7.Get the class name with or without the package
7.6.8.Detect if a package is available
7.6.9.Get the package name of the specified class.
7.6.10.Get the short name of the specified class by striping off the package name.
7.6.11.Get Package Names From Dir
7.6.12.Get non Package Qualified Name
7.6.13.Returns the package portion of the specified class