## 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
`RJavaTools()`

### Method Summary

All Methods Static Methods Concrete Methods
`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)