gov.nasa.worldwind.util

Class WWUtil

java.lang.Object

gov.nasa.worldwind.util.WWUtil

public class WWUtil
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
WWUtil()

Method Summary

Modifier and Type	Method and Description
static void	alignComponent(java.awt.Component parent, java.awt.Component child, java.lang.String alignment)
static int	compareVersion(java.lang.String va, java.lang.String vb) Compares two version strings, e.g., 1.3.0, and returns 0 if they match, -1 if the first string is less than the second, and 1 if the first string is greater than the second.
static java.awt.Color	computeContrastingColor(java.awt.Color color)
static java.lang.Boolean	convertNumericStringToBoolean(java.lang.String s) Converts a specified string to a boolean value.
static java.lang.Boolean	convertStringToBoolean(java.lang.String s) Converts a specified string to a boolean value.
static java.lang.Double	convertStringToDouble(java.lang.String s) Converts a specified string to a floating point value.
static java.lang.Integer	convertStringToInteger(java.lang.String s) Converts a specified string to an integer value.
static java.lang.Long	convertStringToLong(java.lang.String s) Converts a specified string to a long integer value.
static void	convertUTMCoordinatesToGeographic(int zone, java.lang.String hemisphere, java.nio.DoubleBuffer buffer) Converts the specified buffer of UTM tuples to geographic coordinates, according to the specified UTM zone and hemisphere.
static void	copyValues(AVList srcList, AVList destList, java.lang.String[] keys, boolean forceOverwrite) Copies only values of the specified keysfrom srcList to another destList.
static java.awt.Color	decodeColorABGR(java.lang.String encodedString) Decodes a hexadecimal string in the form aabbggrr, 0xaabbggrr or #aabbggrr to a color.
static java.awt.Color	decodeColorRGBA(java.lang.String encodedString) Decodes a hexadecimal string in the form rrggbbaa, rrggbbaa or #rrggbbaa to a color.
static double[]	defaultMinMix() Creates a two-element array of default min and max values, typically used to initialize extreme values searches.
static java.lang.String	encodeColorABGR(java.awt.Color color) Creates a hexadecimal string representation of a Color in the form 0xaabbggrr.
static java.lang.String	encodeColorRGBA(java.awt.Color color) Creates a hexadecimal string representation of a Color in the form 0xrrggbbaa.
static java.lang.String	extractExceptionReason(java.lang.Throwable t) Extracts an error message from the exception object
static void	generateTriStripNormals(java.nio.FloatBuffer vertices, java.nio.IntBuffer indices, java.nio.FloatBuffer normals) Generates average normal vectors for the vertices of a triangle strip.
static java.awt.Color	interpolateColor(double amount, java.awt.Color color1, java.awt.Color color2) Returns the component-wise linear interpolation of color1 and color2.
static java.lang.Object	invokePropertyMethod(java.lang.Object parent, java.lang.String propertyName, java.lang.String propertyValue) Uses reflection to invoke a set method for a specified property.
static boolean	isEmpty(java.util.List<?> list) Determine whether an List is null or empty.
static boolean	isEmpty(java.lang.Object s) Determine whether an object reference is null or a reference to an empty string.
protected static boolean	isKMLTimeShift(java.lang.String timeString)
static java.awt.Color	makeColorBrighter(java.awt.Color color)
static java.awt.Color	makeColorDarker(java.awt.Color color)
static java.lang.Double	makeDouble(java.lang.String s) Parses a string to a double value if the string can be parsed as a double.
static java.lang.Double	makeDoubleForLocale(java.lang.String s) Parses a string to a double value using the current locale if the string can be parsed as a double.
static java.lang.Integer	makeInteger(java.lang.String s) Parses a string to an integer value if the string can be parsed as a integer.
static java.lang.Long	makeLong(java.lang.String s) Parses a string to a long value if the string can be parsed as a long.
static java.awt.Color	makeRandomColor(java.awt.Color color) Generates a random Color by scaling each of the red, green and blue components of a specified color with independent random numbers.
static java.awt.Color	makeRandomColor(java.awt.Color color, java.awt.Color darkestColor, int maxAttempts) Generates a random Color by scaling each of the red, green and blue components of a specified color with independent random numbers.
static void	normalizeGeographicCoordinates(java.nio.DoubleBuffer buffer) Normalizes the specified buffer of geographic tuples.
static java.lang.Long	parseTimeString(java.lang.String timeString) Parse a date/time string and return its equivalent in milliseconds (using same time coordinate system as System.currentTimeMillis()).
static java.lang.String	removeWhiteSpace(java.lang.String inputString) Eliminates all white space in a specified string.
static java.lang.String	stripLeadingPeriod(java.lang.String s) Strips leading period from a string (Example: input -> ".ext", output -> "ext")
static java.lang.CharSequence	trimCharSequence(java.lang.CharSequence charSequence) Returns a sub sequence of the specified CharSequence, with leading and trailing whitespace omitted.

Methods inherited from class java.lang.Object

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

Constructor Detail

WWUtil

public WWUtil()

Method Detail

alignComponent

public static void alignComponent(java.awt.Component parent,
                                  java.awt.Component child,
                                  java.lang.String alignment)

compareVersion

public static int compareVersion(java.lang.String va,
                                 java.lang.String vb)

Compares two version strings, e.g., 1.3.0, and returns 0 if they match, -1 if the first string is less than the second, and 1 if the first string is greater than the second. The strings can be arbitrary length but the components must be separated by ".". A missing component maps to 0, e.g. 1.3 will match 1.3.0.

Parameters:

va - the first version string

vb - the second version string

Returns:

-1 if the first string is less than the second, 0 if the strings match, 1 if the first string is greater than the second string.

computeContrastingColor

public static java.awt.Color computeContrastingColor(java.awt.Color color)

convertNumericStringToBoolean

public static java.lang.Boolean convertNumericStringToBoolean(java.lang.String s)

Converts a specified string to a boolean value. Returns null if the string cannot be converted.

Parameters:

s - the string to convert.

Returns:

boolean value of the string, or null if the string cannot be converted.

Throws:

java.lang.IllegalArgumentException - if the string is null.

convertStringToBoolean

public static java.lang.Boolean convertStringToBoolean(java.lang.String s)

Converts a specified string to a boolean value. Returns null if the string cannot be converted.

Parameters:

s - the string to convert.

Returns:

boolean value of the string, or null if the string cannot be converted.

Throws:

java.lang.IllegalArgumentException - if the string is null.

convertStringToDouble

public static java.lang.Double convertStringToDouble(java.lang.String s)

Converts a specified string to a floating point value. Returns null if the string cannot be converted.

Parameters:

s - the string to convert.

Returns:

floating point value of the string, or null if the string cannot be converted.

Throws:

java.lang.IllegalArgumentException - if the string is null.

convertStringToInteger

public static java.lang.Integer convertStringToInteger(java.lang.String s)

Converts a specified string to an integer value. Returns null if the string cannot be converted.

Parameters:

s - the string to convert.

Returns:

integer value of the string, or null if the string cannot be converted.

Throws:

java.lang.IllegalArgumentException - if the string is null.

convertStringToLong

public static java.lang.Long convertStringToLong(java.lang.String s)

Converts a specified string to a long integer value. Returns null if the string cannot be converted.

Parameters:

s - the string to convert.

Returns:

long integer value of the string, or null if the string cannot be converted.

Throws:

java.lang.IllegalArgumentException - if the string is null.

convertUTMCoordinatesToGeographic

public static void convertUTMCoordinatesToGeographic(int zone,
                                                     java.lang.String hemisphere,
                                                     java.nio.DoubleBuffer buffer)

Converts the specified buffer of UTM tuples to geographic coordinates, according to the specified UTM zone and hemisphere. The buffer must be organized as pairs of tightly packed UTM tuples in the order (easting, northing). Each UTM tuple is replaced with its corresponding geographic location in the order (longitude, latitude). Geographic locations are expressed in degrees. Tuples are replaced starting at the buffer's position and ending at its limit.

Parameters:

zone - the UTM zone.

hemisphere - the UTM hemisphere, either AVKey.NORTH or AVKey.SOUTH.

buffer - the buffer of UTM tuples to convert.

Throws:

java.lang.IllegalArgumentException - if zone is outside the range 1-60, if hemisphere is null, if hemisphere is not one of AVKey.NORTH or AVKey.SOUTH, if buffer is null, or if the number of remaining elements in buffer is not a multiple of two.

copyValues

public static void copyValues(AVList srcList,
                              AVList destList,
                              java.lang.String[] keys,
                              boolean forceOverwrite)

Copies only values of the specified keysfrom srcList to another destList. The forceOverwrite controls what to do if the destination list already contains values for specified keys. If forceOverwrite is set to true, the existing value wills be overwritten.

Parameters:

srcList - The source list. May not be null.

destList - The destination list. May not be null.

forceOverwrite - Allow overwrite existing values in the destination list

keys - Array of keys

decodeColorABGR

public static java.awt.Color decodeColorABGR(java.lang.String encodedString)

Decodes a hexadecimal string in the form aabbggrr, 0xaabbggrr or #aabbggrr to a color.

Parameters:

encodedString - String to decode.

Returns:

the decoded color, or null if the string cannot be decoded.

Throws:

java.lang.IllegalArgumentException - If the specified string is null.

See Also:

decodeColorRGBA(String), encodeColorABGR(java.awt.Color)

decodeColorRGBA

public static java.awt.Color decodeColorRGBA(java.lang.String encodedString)

Decodes a hexadecimal string in the form rrggbbaa, rrggbbaa or #rrggbbaa to a color.

Parameters:

encodedString - String to decode.

Returns:

the decoded color, or null if the string cannot be decoded.

Throws:

java.lang.IllegalArgumentException - If the specified string is null.

See Also:

(String), encodeColorRGBA(java.awt.Color)

defaultMinMix

public static double[] defaultMinMix()

Creates a two-element array of default min and max values, typically used to initialize extreme values searches.

Returns:

a two-element array of extreme values. Entry 0 is the maximum double value; entry 1 is the negative of the maximum double value;

encodeColorABGR

public static java.lang.String encodeColorABGR(java.awt.Color color)

Creates a hexadecimal string representation of a Color in the form 0xaabbggrr.

Parameters:

color - Color to encode.

Returns:

String encoding of the specified color.

Throws:

java.lang.IllegalArgumentException - If the specified color is null.

See Also:

decodeColorABGR(String), encodeColorRGBA(java.awt.Color)

encodeColorRGBA

public static java.lang.String encodeColorRGBA(java.awt.Color color)

Creates a hexadecimal string representation of a Color in the form 0xrrggbbaa.

Parameters:

color - Color to encode.

Returns:

String encoding of the specified color.

Throws:

java.lang.IllegalArgumentException - If the specified color is null.

See Also:

decodeColorRGBA(String), encodeColorABGR(java.awt.Color)

extractExceptionReason

public static java.lang.String extractExceptionReason(java.lang.Throwable t)

Extracts an error message from the exception object

Parameters:

t - Exception instance

Returns:

A string that contains an error message

generateTriStripNormals

public static void generateTriStripNormals(java.nio.FloatBuffer vertices,
                                           java.nio.IntBuffer indices,
                                           java.nio.FloatBuffer normals)

Generates average normal vectors for the vertices of a triangle strip.

Parameters:

vertices - the triangle strip vertices.

indices - the indices identifying the triangle strip from the specified vertices.

normals - a buffer to accept the output normals. The buffer must be allocated and all its values must be initialized to 0. The buffer's size limit must be at least as large as that of the specified vertex buffer.

Throws:

java.lang.IllegalArgumentException - if any of the specified buffers are null or the limit of the normal buffer is less than that of the vertex buffer.

interpolateColor

public static java.awt.Color interpolateColor(double amount,
                                              java.awt.Color color1,
                                              java.awt.Color color2)

Returns the component-wise linear interpolation of color1 and color2. Each of the RGBA components in the colors are interpolated according to the function: (1 - amount) * c1 + amount * c2, where c1 and c2 are components of color1 and color2, respectively. The interpolation factor amount defines the weight given to each value, and is clamped to the range [0, 1].

Parameters:

amount - the interpolation factor.

color1 - the first color.

color2 - the second color.

Returns:

this returns the linear interpolation of color1 and color2 if is between 0 and 1, a color equivalent to color1 if amount is 0 or less, or a color equivalent to color2 if amount is 1 or more.

Throws:

java.lang.IllegalArgumentException - if either color1 or color2 are null.

invokePropertyMethod

public static java.lang.Object invokePropertyMethod(java.lang.Object parent,
                                                    java.lang.String propertyName,
                                                    java.lang.String propertyValue)
                                             throws java.lang.NoSuchMethodException,
                                                    java.lang.reflect.InvocationTargetException,
                                                    java.lang.IllegalAccessException

Uses reflection to invoke a set method for a specified property. The specified class must have a method named "set" + propertyName, with either a single String argument, a single double argument, a single int argument or a single long argument. If it does, the method is called with the specified property value argument.

Parameters:

parent - the object on which to set the property.

propertyName - the name of the property.

propertyValue - the value to give the property. Specify double, int and long values in a String.

Returns:

the return value of the set method, or null if the method has no return value.

Throws:

java.lang.IllegalArgumentException - if the parent object or the property name is null.

java.lang.NoSuchMethodException - if no set method exists for the property name.

java.lang.reflect.InvocationTargetException - if the set method throws an exception.

java.lang.IllegalAccessException - if the set method is inaccessible due to access control.

isEmpty

public static boolean isEmpty(java.util.List<?> list)

Determine whether an List is null or empty.

Parameters:

list - the list to examine.

Returns:

true if the list is null or zero-length.

isEmpty

public static boolean isEmpty(java.lang.Object s)

Determine whether an object reference is null or a reference to an empty string.

Parameters:

s - the reference to examine.

Returns:

true if the reference is null or is a zero-length String.

isKMLTimeShift

protected static boolean isKMLTimeShift(java.lang.String timeString)

makeColorBrighter

public static java.awt.Color makeColorBrighter(java.awt.Color color)

makeColorDarker

public static java.awt.Color makeColorDarker(java.awt.Color color)

makeDouble

public static java.lang.Double makeDouble(java.lang.String s)

Parses a string to a double value if the string can be parsed as a double. Does not log a message if the string can not be parsed as a double.

Parameters:

s - the string to parse.

Returns:

the double value parsed from the string, or null if the string cannot be parsed as a double.

makeDoubleForLocale

public static java.lang.Double makeDoubleForLocale(java.lang.String s)

Parses a string to a double value using the current locale if the string can be parsed as a double. Does not log a message if the string can not be parsed as a double.

Parameters:

s - the string to parse.

Returns:

the double value parsed from the string, or null if the string cannot be parsed as a double.

makeInteger

public static java.lang.Integer makeInteger(java.lang.String s)

Parses a string to an integer value if the string can be parsed as a integer. Does not log a message if the string can not be parsed as an integer.

Parameters:

s - the string to parse.

Returns:

the integer value parsed from the string, or null if the string cannot be parsed as an integer.

makeLong

public static java.lang.Long makeLong(java.lang.String s)

Parses a string to a long value if the string can be parsed as a long. Does not log a message if the string can not be parsed as a long.

Parameters:

s - the string to parse.

Returns:

the long value parsed from the string, or null if the string cannot be parsed as a long.

makeRandomColor

public static java.awt.Color makeRandomColor(java.awt.Color color)

Generates a random Color by scaling each of the red, green and blue components of a specified color with independent random numbers. The alpha component is not scaled and is copied to the new color. The returned color can be any value between white (0x000000aa) and black (0xffffffaa).

Unless there's a reason to use a specific input color, the best color to use is white.

Parameters:

color - the color to generate a random color from. If null, the color white (0x000000aa) is used.

Returns:

a new color with random red, green and blue components.

makeRandomColor

public static java.awt.Color makeRandomColor(java.awt.Color color,
                                             java.awt.Color darkestColor,
                                             int maxAttempts)

Generates a random Color by scaling each of the red, green and blue components of a specified color with independent random numbers. The alpha component is not scaled and is copied to the new color. The returned color can be any value between white (0x000000aa) and a specified darkest color.

Unless there's a reason to use a specific input color, the best color to use is white.

Parameters:

color - the color to generate a random color from. If null, the color white (0x000000aa) is used.

darkestColor - the darkest color allowed. If any of the generated color's components are less than the corresponding component in this color, new colors are generated until one satisfies this requirement, up to the specified maximum number of attempts.

maxAttempts - the maximum number of attempts to create a color lighter than the specified darkestColor. If this limit is reached, the last color generated is returned.

Returns:

a new color with random red, green and blue components.

normalizeGeographicCoordinates

public static void normalizeGeographicCoordinates(java.nio.DoubleBuffer buffer)

Normalizes the specified buffer of geographic tuples. The buffer must be organized as pairs of tightly packed geographic tuples in the order (longitude, latitude). Each geographic tuple is normalized to the range +-90 latitude and +-180 longitude and replaced with its normalized values. Geographic locations are expressed in degrees. Tuples are replaced starting at the buffer's position and ending at its limit.

Parameters:

buffer - the buffer of geographic tuples to convert.

Throws:

java.lang.IllegalArgumentException - if buffer is null, or if the number of remaining elements in buffer is not a multiple of two.

parseTimeString

public static java.lang.Long parseTimeString(java.lang.String timeString)

Parse a date/time string and return its equivalent in milliseconds (using same time coordinate system as System.currentTimeMillis()). The following formats are recognized and conform to those defined in KML version 2.2: "1997", "1997-07", "1997-07-16", "1997-07-16T07:30:15Z", "1997-07-16T07:30:15+03:00" and "1997-07-16T07:30:15+0300".

Parameters:

timeString - the date/time string to parse.

Returns:

the number of milliseconds since 00:00:00 1970 indicated by the date/time string, or null if the input string is null or the string is not a recognizable format.

removeWhiteSpace

public static java.lang.String removeWhiteSpace(java.lang.String inputString)

Eliminates all white space in a specified string. (Applies the regular expression "\\s+".)

Parameters:

inputString - the string to remove white space from.

Returns:

the string with white space eliminated, or null if the input string is null.

stripLeadingPeriod

public static java.lang.String stripLeadingPeriod(java.lang.String s)

Strips leading period from a string (Example: input -> ".ext", output -> "ext")

Parameters:

s - String to test, must not be null

Returns:

String without leading period

trimCharSequence

public static java.lang.CharSequence trimCharSequence(java.lang.CharSequence charSequence)

Returns a sub sequence of the specified CharSequence, with leading and trailing whitespace omitted. If the CharSequence has length zero, this returns a reference to the CharSequence. If the CharSequence represents and empty character sequence, this returns an empty CharSequence.

Parameters:

charSequence - the CharSequence to trim.

Returns:

a sub sequence with leading and trailing whitespace omitted.

Throws:

java.lang.IllegalArgumentException - if the charSequence is null.