com.devexperts.util

Class SystemProperties

java.lang.Object

com.devexperts.util.SystemProperties

public final class SystemProperties
extends Object

Utility methods for retrieving system properties without getting a SecurityException. Unless otherwise is specified all methods of this class conceal and log any exceptions and return default value in case of any failure.

Method Summary

Modifier and Type	Method and Description
static boolean	getBooleanProperty(Class<?> c, String propName, boolean defValue) Gets the boolean system property indicated by the specified class and property name.
static boolean	getBooleanProperty(String key, boolean defValue) Gets the boolean system property indicated by the specified key.
static int	getIntProperty(Class<?> c, String propName, int defValue) Gets the integer system property indicated by the specified class and property name.
static int	getIntProperty(Class<?> c, String propName, int defValue, int minValue, int maxValue) Gets the integer system property indicated by the specified class and property name and shrinks it into specified range.
static int	getIntProperty(String key, int defValue) Gets the integer system property indicated by the specified key.
static int	getIntProperty(String key, int defValue, int minValue, int maxValue) Gets the integer system property indicated by the specified key and shrinks it into specified range.
static long	getLongProperty(Class<?> c, String propName, long defValue) Gets the long system property indicated by the specified class and property name.
static long	getLongProperty(Class<?> c, String propName, long defValue, long minValue, long maxValue) Gets the long system property indicated by the specified class and property name and shrinks it into specified range.
static long	getLongProperty(String key, long defValue) Gets the long system property indicated by the specified key.
static long	getLongProperty(String key, long defValue, long minValue, long maxValue) Gets the long system property indicated by the specified key and shrinks it into specified range.
static String	getProperty(Class<?> c, String propName, String defValue) Gets the string system property indicated by the specified class and property name.
static String	getProperty(String key, String defValue) Gets the string system property indicated by the specified key.
static boolean	parseBooleanValue(String value) Utility method that parses boolean value from a string.

Methods inherited from class java.lang.Object

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

Method Detail

getProperty

public static String getProperty(String key,
                                 String defValue)

Gets the string system property indicated by the specified key.

This method behaves as System.getProperty(key, defValue), except for the fact that it conceals SecurityException.

Parameters:

key - system property key

defValue - default value

Returns:

string system property indicated by the specified key or default value if failed to acquire the property

See Also:

System.getProperty(key, def)

getProperty

public static String getProperty(Class<?> c,
                                 String propName,
                                 String defValue)

Gets the string system property indicated by the specified class and property name. The property key is equal to c.getName() + "." + propName.

This method behaves as System.getProperty(key, defValue), except for the fact that it conceals SecurityException.

Parameters:

c - the class that the property is part of

propName - property name in the class. Use camelCase naming starting with lowercase first letter

defValue - default value

Returns:

string system property indicated by the specified key or default value if failed to acquire the property

See Also:

System.getProperty(key, def)

getIntProperty

public static int getIntProperty(String key,
                                 int defValue)

Gets the integer system property indicated by the specified key.

This method can parse numbers in decimal, hexadecimal, and octal radix (the same way as Integer.getInteger(key, defValue) method does).

Parameters:

key - system property key

defValue - default value

Returns:

integer system property indicated by the specified key or default value if failed to acquire or parse the property

getIntProperty

public static int getIntProperty(Class<?> c,
                                 String propName,
                                 int defValue)

Gets the integer system property indicated by the specified class and property name. The property key is equal to c.getName() + "." + propName.

This method can parse numbers in decimal, hexadecimal, and octal radix (the same way as Integer.getInteger(key, defValue) method does).

Parameters:

c - the class that the property is part of

propName - property name in the class. Use camelCase naming starting with lowercase first letter

defValue - default value

Returns:

integer system property indicated by the specified key or default value if failed to acquire or parse the property

getIntProperty

public static int getIntProperty(String key,
                                 int defValue,
                                 int minValue,
                                 int maxValue)

Gets the integer system property indicated by the specified key and shrinks it into specified range.

This methods behaves likely to getIntProperty(key, defValue) but if the resulting value is less than minValue or greater than maxValue a warning is logged and the corresponding boundary value is returned.

Parameters:

key - system property key

defValue - default value

minValue - minimum allowable value

maxValue - maximum allowable value

Returns:

integer system property indicated by the specified key or default value if failed to acquire or parse the property

Throws:

IllegalArgumentException - if minValue≤defValue≤maxValue condition breaks

getIntProperty

public static int getIntProperty(Class<?> c,
                                 String propName,
                                 int defValue,
                                 int minValue,
                                 int maxValue)

Gets the integer system property indicated by the specified class and property name and shrinks it into specified range. The property key is equal to c.getName() + "." + propName.

This methods behaves likely to getIntProperty(key, defValue) but if the resulting value is less than minValue or greater than maxValue a warning is logged and the corresponding boundary value is returned.

Parameters:

c - the class that the property is part of

propName - property name in the class. Use camelCase naming starting with lowercase first letter

defValue - default value

minValue - minimum allowable value

maxValue - maximum allowable value

Returns:

integer system property indicated by the specified key or default value if failed to acquire or parse the property

Throws:

IllegalArgumentException - if minValue≤defValue≤maxValue condition breaks

getLongProperty

public static long getLongProperty(String key,
                                   long defValue)

Gets the long system property indicated by the specified key.

This method can parse numbers in decimal, hexadecimal, and octal radix (the same way as Long.getLong(key, defValue) method does).

Parameters:

key - system property key

defValue - default value

Returns:

long system property indicated by the specified key or default value if failed to acquire or parse the property

getLongProperty

public static long getLongProperty(Class<?> c,
                                   String propName,
                                   long defValue)

Gets the long system property indicated by the specified class and property name. The property key is equal to c.getName() + "." + propName.

This method can parse numbers in decimal, hexadecimal, and octal radix (the same way as Long.getLong(key, defValue) method does).

Parameters:

c - the class that the property is part of

propName - property name in the class. Use camelCase naming starting with lowercase first letter

defValue - default value

Returns:

long system property indicated by the specified key or default value if failed to acquire or parse the property

getLongProperty

public static long getLongProperty(String key,
                                   long defValue,
                                   long minValue,
                                   long maxValue)

Gets the long system property indicated by the specified key and shrinks it into specified range.

This methods behaves likely to getLongProperty(key, defValue) but if the resulting value is less than minValue or greater than maxValue a warning is logged and the corresponding boundary value is returned.

Parameters:

key - system property key

defValue - default value

minValue - minimum allowable value

maxValue - maximum allowable value

Returns:

long system property indicated by the specified key or default value if failed to acquire or parse the property

Throws:

IllegalArgumentException - if minValue≤defValue≤maxValue condition breaks

getLongProperty

public static long getLongProperty(Class<?> c,
                                   String propName,
                                   long defValue,
                                   long minValue,
                                   long maxValue)

Gets the long system property indicated by the specified class and property name and shrinks it into specified range. The property key is equal to c.getName() + "." + propName.

This methods behaves likely to getLongProperty(key, defValue) but if the resulting value is less than minValue or greater than maxValue a warning is logged and the corresponding boundary value is returned.

Parameters:

c - the class that the property is part of

propName - property name in the class. Use camelCase naming starting with lowercase first letter

defValue - default value

minValue - minimum allowable value

maxValue - maximum allowable value

Returns:

long system property indicated by the specified key or default value if failed to acquire or parse the property

Throws:

IllegalArgumentException - if minValue≤defValue≤maxValue condition breaks

getBooleanProperty

public static boolean getBooleanProperty(String key,
                                         boolean defValue)

Gets the boolean system property indicated by the specified key.

Unlike Boolean.getBoolean(key) this method recognizes defined properties with empty values as true and returns the default value (and logs an error) if the value of a specified property is neither of "true", "false" or "" (case-insensetively).

Parameters:

key - system property key

defValue - default value

Returns:

boolean system property indicated by the specified key or default value if failed to acquire or parse the property

getBooleanProperty

public static boolean getBooleanProperty(Class<?> c,
                                         String propName,
                                         boolean defValue)

Gets the boolean system property indicated by the specified class and property name. The property key is equal to c.getName() + "." + propName.

Unlike Boolean.getBoolean(key) this method recognizes defined properties with empty values as true and returns the default value (and logs an error) if the value of a specified property is neither of "true", "false" or "" (case-insensetively).

Parameters:

c - the class that the property is part of

propName - property name in the class. Use camelCase naming starting with lowercase first letter

defValue - default value

Returns:

boolean system property indicated by the specified key or default value if failed to acquire or parse the property

parseBooleanValue

public static boolean parseBooleanValue(String value)
                                 throws IllegalArgumentException

Utility method that parses boolean value from a string. This method recognizes "" (empty string) and "true" as true and "false" as false (case-insensitively); all other values are considered invalid.

Parameters:

value - string to parse

Returns:

boolean value, represented by given string

Throws:

IllegalArgumentException - if the string was neither of "", "true" or "false" (case-insensitively)

NullPointerException - if value is null