## Class RJavaTools

- java.lang.Object
- - RJavaTools

-     public class RJavaTools
      extends java.lang.Object

  Tools used internally by rJava. The method lookup code is heavily based on ReflectionTools by Romain Francois <francoisromain@free.fr> licensed under GPL v2 or higher.

- - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `RJavaTools()` |

  - ### Method Summary

    All Methods Static Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `static boolean` | `classHasClass​(java.lang.Class cl, java.lang.String name, boolean staticRequired)` | Checks if the specified class has the given inner class.
    `static boolean` | `classHasField​(java.lang.Class cl, java.lang.String name, boolean staticRequired)` | Checks if the specified class has the given field.
    `static boolean` | `classHasMethod​(java.lang.Class cl, java.lang.String name, boolean staticRequired)` | Checks if the specified class has the given method.
    `static java.lang.Class` | `getClass​(java.lang.Class cl, java.lang.String name, boolean staticRequired)` | Returns an inner class of the class with the given simple name
    `static java.lang.Class[]` | `getClasses​(java.lang.Object o)` | Returns the list of classes of the object
    `static java.lang.String[]` | `getClassNames​(java.lang.Object o)` | Returns the list of class names of the object
    `static java.lang.String` | `getCompletionName​(java.lang.reflect.Member m)` | Completion name of a member.
    `static java.lang.reflect.Constructor` | `getConstructor​(java.lang.Class o_clazz, java.lang.Class[] arg_clazz, boolean[] arg_is_null)` | Attempts to find the best-matching constructor of the class o_clazz with the parameter types arg_clazz
    `static java.lang.String[]` | `getFieldNames​(java.lang.Class cl, boolean staticRequired)` | Returns the names of the fields of a given class
    `static java.lang.String` | `getFieldTypeName​(java.lang.Class cl, java.lang.String field)` |
    `static java.lang.reflect.Method` | `getMethod​(java.lang.Class o_clazz, java.lang.String name, java.lang.Class[] arg_clazz, boolean[] arg_is_null)` | Attempts to find the best-matching method of the class `o_clazz` with the method name `name` and arguments types defined by `arg_clazz`.
    `static java.lang.String[]` | `getMethodNames​(java.lang.Class cl, boolean staticRequired)` | Returns the completion names of the methods of a given class.
    `static java.lang.String[]` | `getSimpleClassNames​(java.lang.Object o, boolean addConditionClasses)` | Returns the list of simple class names of the object
    `static java.lang.Class[]` | `getStaticClasses​(java.lang.Class cl)` | Returns the static inner classes of the class
    `static java.lang.reflect.Field[]` | `getStaticFields​(java.lang.Class cl)` | Returns the static fields of the class
    `static java.lang.reflect.Method[]` | `getStaticMethods​(java.lang.Class cl)` | Returns the static methods of the class
    `static boolean` | `hasClass​(java.lang.Object o, java.lang.String name)` | Checks if the class of the object has the given inner class.
    `static boolean` | `hasField​(java.lang.Object o, java.lang.String name)` | Checks if the class of the object has the given field.
    `static boolean` | `hasMethod​(java.lang.Object o, java.lang.String name)` | Checks if the class of the object has the given method.
    `static java.lang.Object` | `invokeMethod​(java.lang.Class o_clazz, java.lang.Object o, java.lang.String name, java.lang.Object[] args, java.lang.Class[] clazzes)` | Invoke a method of a given class
    `static boolean` | `isStatic​(java.lang.Class clazz)` | Indicates if a class is static
    `static boolean` | `isStatic​(java.lang.reflect.Member member)` | Indicates if a member of a Class (field, method ) is static
    `static java.lang.Object` | `newInstance​(java.lang.Class o_clazz, java.lang.Object[] args, java.lang.Class[] clazzes)` | Object creator.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### RJavaTools

          public RJavaTools()

  - ### Method Detail

    - #### getClass

          public static java.lang.Class getClass​(java.lang.Class cl,
                                                 java.lang.String name,
                                                 boolean staticRequired)

      Returns an inner class of the class with the given simple name
      Parameters:
        `cl` - class
        `name` - simple name of the inner class
        `staticRequired` - boolean, if `true` the inner class is required to be static

    - #### getStaticClasses

          public static java.lang.Class[] getStaticClasses​(java.lang.Class cl)

      Returns the static inner classes of the class
      Parameters:
        `cl` - class
      Returns:
        an array of classes or null if cl does not have static inner classes

    - #### isStatic

          public static boolean isStatic​(java.lang.Class clazz)

      Indicates if a class is static
      Parameters:
        `clazz` - class
      Returns:
        true if the class is static

    - #### getStaticFields

          public static java.lang.reflect.Field[] getStaticFields​(java.lang.Class cl)

      Returns the static fields of the class
      Parameters:
        `cl` - class
      Returns:
        an array of static fields

    - #### getStaticMethods

          public static java.lang.reflect.Method[] getStaticMethods​(java.lang.Class cl)

      Returns the static methods of the class
      Parameters:
        `cl` - class
      Returns:
        an array of static fields

    - #### getFieldNames

          public static java.lang.String[] getFieldNames​(java.lang.Class cl,
                                                         boolean staticRequired)

      Returns the names of the fields of a given class
      Parameters:
        `cl` - class
        `staticRequired` - if true only static fields are returned
      Returns:
        the public (and maybe only static) names of the fields.

    - #### getMethodNames

          public static java.lang.String[] getMethodNames​(java.lang.Class cl,
                                                          boolean staticRequired)

      Returns the completion names of the methods of a given class. See the getMethodCompletionName method below
      Parameters:
        `cl` - class
        `staticRequired` - if true only static methods are returned
      Returns:
        the public (and maybe only static) names of the methods.

    - #### getCompletionName

          public static java.lang.String getCompletionName​(java.lang.reflect.Member m)

      Completion name of a member.

      For fields, it just returns the name of the fields

      For methods, this returns the name of the method plus a suffix that depends on the number of arguments of the method.

      The string "()" is added if the method has no arguments, and the string "(" is added if the method has one or more arguments.

    - #### isStatic

          public static boolean isStatic​(java.lang.reflect.Member member)

      Indicates if a member of a Class (field, method ) is static
      Parameters:
        `member` - class member
      Returns:
        true if the member is static

    - #### hasField

          public static boolean hasField​(java.lang.Object o,
                                         java.lang.String name)

      Checks if the class of the object has the given field. The getFields method of Class is used so only public fields are checked
      Parameters:
        `o` - object
        `name` - name of the field
      Returns:
        `true` if the class of `o` has the field `name`

    - #### hasClass

          public static boolean hasClass​(java.lang.Object o,
                                         java.lang.String name)

      Checks if the class of the object has the given inner class. The getClasses method of Class is used so only public classes are checked
      Parameters:
        `o` - object
        `name` - (simple) name of the inner class
      Returns:
        `true` if the class of `o` has the class `name`

    - #### classHasField

          public static boolean classHasField​(java.lang.Class cl,
                                              java.lang.String name,
                                              boolean staticRequired)

      Checks if the specified class has the given field. The getFields method of Class is used so only public fields are checked
      Parameters:
        `cl` - class object
        `name` - name of the field
        `staticRequired` - if `true` then the field is required to be static
      Returns:
        `true` if the class `cl` has the field `name`

    - #### classHasMethod

          public static boolean classHasMethod​(java.lang.Class cl,
                                               java.lang.String name,
                                               boolean staticRequired)

      Checks if the specified class has the given method. The getMethods method of Class is used so only public methods are checked
      Parameters:
        `cl` - class
        `name` - name of the method
        `staticRequired` - if `true` then the method is required to be static
      Returns:
        `true` if the class `cl` has the method `name`

    - #### classHasClass

          public static boolean classHasClass​(java.lang.Class cl,
                                              java.lang.String name,
                                              boolean staticRequired)

      Checks if the specified class has the given inner class. The getClasses method of Class is used so only public classes are checked
      Parameters:
        `cl` - class
        `name` - name of the inner class
        `staticRequired` - if `true` then the method is required to be static
      Returns:
        `true` if the class `cl` has the field `name`

    - #### hasMethod

          public static boolean hasMethod​(java.lang.Object o,
                                          java.lang.String name)

      Checks if the class of the object has the given method. The getMethods method of Class is used so only public methods are checked
      Parameters:
        `o` - object
        `name` - name of the method
      Returns:
        `true` if the class of `o` has the field `name`

    - #### newInstance

          public static java.lang.Object newInstance​(java.lang.Class o_clazz,
                                                     java.lang.Object[] args,
                                                     java.lang.Class[] clazzes)
                                              throws java.lang.Throwable

      Object creator. Find the best constructor based on the parameter classes and invoke newInstance on the resolved constructor
      Throws:
        `java.lang.Throwable`

    - #### invokeMethod

          public static java.lang.Object invokeMethod​(java.lang.Class o_clazz,
                                                      java.lang.Object o,
                                                      java.lang.String name,
                                                      java.lang.Object[] args,
                                                      java.lang.Class[] clazzes)
                                               throws java.lang.Throwable

      Invoke a method of a given class

      First the appropriate method is resolved by getMethod and then invokes the method

      Throws:
        `java.lang.Throwable`

    - #### getConstructor

          public static java.lang.reflect.Constructor getConstructor​(java.lang.Class o_clazz,
                                                                     java.lang.Class[] arg_clazz,
                                                                     boolean[] arg_is_null)
                                                              throws java.lang.SecurityException,
                                                                     java.lang.NoSuchMethodException

      Attempts to find the best-matching constructor of the class o_clazz with the parameter types arg_clazz
      Parameters:
        `o_clazz` - Class to look for a constructor
        `arg_clazz` - parameter types
        `arg_is_null` - indicates if each argument is null
      Returns:
        `null` if no constructor is found, or the constructor
      Throws:
        `java.lang.SecurityException`
        `java.lang.NoSuchMethodException`

    - #### getMethod

          public static java.lang.reflect.Method getMethod​(java.lang.Class o_clazz,
                                                           java.lang.String name,
                                                           java.lang.Class[] arg_clazz,
                                                           boolean[] arg_is_null)
                                                    throws java.lang.SecurityException,
                                                           java.lang.NoSuchMethodException

      Attempts to find the best-matching method of the class `o_clazz` with the method name `name` and arguments types defined by `arg_clazz`. The lookup is performed by finding the most specific methods that matches the supplied arguments (see also `isMoreSpecific(java.lang.reflect.Method, java.lang.reflect.Method)`).
      Parameters:
        `o_clazz` - class in which to look for the method
        `name` - method name
        `arg_clazz` - an array of classes defining the types of arguments
        `arg_is_null` - indicates if each argument is null
      Returns:
        `null` if no matching method could be found or the best matching method.
      Throws:
        `java.lang.SecurityException`
        `java.lang.NoSuchMethodException`

    - #### getClasses

          public static java.lang.Class[] getClasses​(java.lang.Object o)

      Returns the list of classes of the object
      Parameters:
        `o` - an Object

    - #### getClassNames

          public static java.lang.String[] getClassNames​(java.lang.Object o)

      Returns the list of class names of the object
      Parameters:
        `o` - an Object

    - #### getSimpleClassNames

          public static java.lang.String[] getSimpleClassNames​(java.lang.Object o,
                                                               boolean addConditionClasses)

      Returns the list of simple class names of the object
      Parameters:
        `o` - an Object

    - #### getFieldTypeName

          public static java.lang.String getFieldTypeName​(java.lang.Class cl,
                                                          java.lang.String field)

      Parameters:
        `cl` - class
        `field` - name of the field
      Returns:
        the class name of the field of the class (or null) if the class does not have the given field)