edu.tum.cs.commons.options
Class Options

java.lang.Object
  edu.tum.cs.commons.options.Options

public class Options
extends Object

This class offers a safe and flexible interface to Java properties files. Property files must follow the format for Java properties files. See Javadoc of Properties for details.

Version:

$Rev: 26268 $

Author:

Florian Deissenboeck, Axel Gerster, $Author: juergens $

See Also:

Properties

Rating:

GREEN Hash: 9DD87B7C40B4E1B84D1F15B00CA3798A

Nested Class Summary

static class

Options.ValueConversionException Exception objects of this class are possibly returned by getBooleanValue(String)and getIntValue(String), if corresponding options don't have a boolean respectively integer value.

Field Summary

static int

OPTION_NOT_PRESENT Returned by countValues when trying to count values of a non-present option.

Constructor Summary

Options()
Construct a new Option object holding now options.

Method Summary

int	countValues(String option) Count the space separated values of an option.
boolean	getBooleanValue(String option) Get the value for an option as boolean.
boolean	getBooleanValue(String option, boolean defaultValue) Same as getBooleanValue(String)but allows to specify a default value.
<T extends Enum<T>> T	getEnumValue(String option, Class<T> enumType) Get the value for an option as instance of an enumeration.
<T extends Enum<T>> T	getEnumValue(String option, T defaultValue, Class<T> enumType) Same as getEnumValue(String, Class) but allows to specify default value.
float	getFloatValue(String option) Get the value for an option as float.
int	getIntValue(String option) Get the value for an option as int.
int	getIntValue(String option, int defaultValue) Same as getIntValue(String)but allows to specify a default value.
String	getValue(String option) Gets the value for a specified option.
String	getValue(String option, String defaultValue) Return the value for a specified option or a default value if option is not present.
String[]	getValues(String option) Returns the space separated value of an option as array.
boolean	hasBooleanValue(String option) Checks if the specified option is present and has a boolean value.
<T extends Enum<T>> boolean	hasEnumValue(String option, Class<T> enumType) Checks if the specified option is present and has a legal value.
boolean	hasFloatValue(String option) Checks if the specified option is present and has a float value.
boolean	hasIntValue(String option) Checks if the specified option is present and has a int value.
boolean	hasOption(String option) Checks if a specified option is present.
boolean	hasValue(String option) Checks if specified option has a value.
void	init() Init empty Options object.
void	init(String filename) This initalizes the Options object by reading a properties file.
boolean	setOption(String option, String value) Sets and option.
String	toString() Returns a list with key-value-pairs as string.

Methods inherited from class java.lang.Object

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

Field Detail

OPTION_NOT_PRESENT

public static final int OPTION_NOT_PRESENT

Returned by countValues when trying to count values of a non-present option.

See Also:

Constant Field Values

Constructor Detail

Options

public Options()

Construct a new Option object holding now options. Use methods init(String)or setOption(String, String)to store options.

Method Detail

init

public void init(String filename)
          throws IOException

This initalizes the Options object by reading a properties file.

Parameters:

filename - full-qualified name of the properties file

Throws:

IOException - Thrown if an I/O problem is encountered while reading properties file.

init

public void init()

Init empty Options object. Existing options are cleared.

setOption

public boolean setOption(String option,
                         String value)

Sets and option. Setting an already existing option overwrites current value.

Parameters:

option - name of the option

value - option's value, must have same format as defined in the properties file

Returns:

true if option was alreay present, false otherwise

getValue

public String getValue(String option)

Gets the value for a specified option.

Parameters:

option - the name of the option

Returns:

the option's value, if the option is not present or has a null value null is returned. If the option has a space separated value list, the whole list is returned. Use getValues(String)to access single values.

getValue

public String getValue(String option,
                       String defaultValue)

Return the value for a specified option or a default value if option is not present.

Parameters:

option - name of the option

defaultValue - default value to use, if option is not present

Returns:

the option's value or the default value

getValues

public String[] getValues(String option)

Returns the space separated value of an option as array. A option might have more the one space separated value. This method returns them as an array. To allow values containing spaces use double quotes.

Example: For the following line in a properties file

option=value1 value2 "value 3" value4

the method returns this array

a[0] = "value1"
a[1] = "value2"
a[2] = "value 3"
a[3] = "value4"


Parameters:

option - name of the option

Returns:

the array as desribed above

hasBooleanValue

public boolean hasBooleanValue(String option)

Checks if the specified option is present and has a boolean value. Boolean values are true,false, yes and no

Parameters:

option - name of the option

Returns:

if the option is present and has a boolean value true is returned, otherwise false

getBooleanValue

public boolean getBooleanValue(String option)
                        throws Options.ValueConversionException

Get the value for an option as boolean.

Parameters:

option - name of the option

Returns:

the value of this option

Throws:

Options.ValueConversionException - if the option doesn't have a boolean value. Use hasBooleanValue(String)method or default value enabled version getBooleanValue(String, boolean)of this method to avoid conversion problems.

getEnumValue

public <T extends Enum<T>> T getEnumValue(String option,
                                          Class<T> enumType)
                               throws Options.ValueConversionException

Get the value for an option as instance of an enumeration. Enumeration names are matched in non case-sensitive way. Dashes in values are replaced by underscores.

Typical usage is:

 Colors color = options.getEnumValue("enum1", Colors.class);
 

where Colors is an enumeration.

Type Parameters:

T - the enumeration

Parameters:

option - the name of the option

enumType - the enumeration type

Returns:

the enumeration entry

Throws:

Options.ValueConversionException - if the option doesn't have a value of the specified enumeration. Use hasEnumValue(String, Class)method or default value enabled version getEnumValue(String, Enum, Class)of this method to avoid conversion problems.

getEnumValue

public <T extends Enum<T>> T getEnumValue(String option,
                                          T defaultValue,
                                          Class<T> enumType)

Same as getEnumValue(String, Class) but allows to specify default value.

Type Parameters:

T - the enumeration

Parameters:

option - the name of the option

enumType - the enumeration type

Returns:

the enumeration entry

hasEnumValue

public <T extends Enum<T>> boolean hasEnumValue(String option,
                                                Class<T> enumType)

Checks if the specified option is present and has a legal value.

Parameters:

option - name of the option

Returns:

if the option is present and has a legal value true is returned, otherwise false

getIntValue

public int getIntValue(String option)
                throws Options.ValueConversionException

Get the value for an option as int.

Parameters:

option - name of the option

Returns:

the value of this option

Throws:

Options.ValueConversionException

Options.ValueConversionException - if the option doesn't have a int value. Use hasIntValue(String)method or default value enabled version getIntValue(String, int)of this method to avoid conversion problems.

hasIntValue

public boolean hasIntValue(String option)

Checks if the specified option is present and has a int value.

Parameters:

option - name of the option

Returns:

if the option is present and has a int value true is returned, otherwise false

getBooleanValue

public boolean getBooleanValue(String option,
                               boolean defaultValue)

Same as getBooleanValue(String)but allows to specify a default value.

Parameters:

option - name of the option

defaultValue - default value

Returns:

return the value of the option if option is present and has a boolean value, otherwise the default value is returned

getIntValue

public int getIntValue(String option,
                       int defaultValue)

Same as getIntValue(String)but allows to specify a default value.

Parameters:

option - name of the option

defaultValue - default value

Returns:

return the value of the option if option is present and has an integer value, otherwise the default value is returned

hasOption

public boolean hasOption(String option)

Checks if a specified option is present.

Parameters:

option - name of the option

Returns:

true if option is present, false otherwise

hasValue

public boolean hasValue(String option)

Checks if specified option has a value.

Parameters:

option - name of the option

Returns:

true if option is present and has a value, false otherwise (even if option is present but doesn't have a value)

countValues

public int countValues(String option)

Count the space separated values of an option. Double quotes are taken into account.

Parameters:

option - name of the option

Returns:

value count

toString

public String toString()

Returns a list with key-value-pairs as string.

Overrides:

toString in class Object

Returns:

key-value-pairs as string

getFloatValue

public float getFloatValue(String option)
                    throws Options.ValueConversionException

Get the value for an option as float.

Parameters:

option - name of the option

Returns:

the value of this option

Throws:

Options.ValueConversionException - if the option doesn't have a float value.

hasFloatValue

public boolean hasFloatValue(String option)

Checks if the specified option is present and has a float value.

Parameters:

option - name of the option

Returns:

if the option is present and has a float value true is returned, otherwise false