org.checkerframework.javacutil

Class SystemUtil

java.lang.Object

org.checkerframework.javacutil.SystemUtil

public class SystemUtil
extends Object

This file contains basic utility functions.

Constructor Summary

Constructors

Constructor and Description
SystemUtil()

Method Summary

Modifier and Type	Method and Description
static <T> T[]	concatenate(T[] array1, T... array2) Concatenates two arrays.
static <T> T[]	concatenate(T firstElt, T[] array, T lastElt) Concatenates an element, an array, and an element.
static boolean	getBooleanSystemProperty(String key) Return true if the system property is set to "true".
static boolean	getBooleanSystemProperty(String key, boolean defaultValue) Return its boolean value if the system property is set.
static int	getJreVersion() Returns the major JRE version.
static @Nullable String	getReleaseValue(ProcessingEnvironment env) Returns the release value passed to the compiler or null if release was not passed.
static @Nullable String	getToolsJar() Returns the pathname to the tools.jar file, or null if it does not exist.
static String	join(CharSequence delimiter, Iterable<?> values) Deprecated. use UtilPlume.join
static <T> String	join(CharSequence delimiter, T[] objs) Deprecated. use UtilPlume.join
static String	joinLines(Iterable<? extends Object> v) Deprecated. use UtilPlume.joinLines
static <T> String	joinLines(T... a) Deprecated. use UtilPlume.joinLines
static List<String>	readFile(File argFile) Return a list of Strings, one per line of the file.
static void	sleep(long millis) Like Thread.sleep, but does not throw any exceptions, so it is easier for clients to use.

Methods inherited from class java.lang.Object

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

Constructor Detail

SystemUtil

public SystemUtil()

Method Detail

readFile

public static List<String> readFile(File argFile)
                             throws IOException

Return a list of Strings, one per line of the file.

Parameters:

argFile - argument file

Returns:

a list of Strings, one per line of the file

Throws:

IOException - when reading the argFile

join

@Deprecated
public static <T> String join(CharSequence delimiter,
                                          T[] objs)

Deprecated. use UtilPlume.join

Returns a new String composed of the string representations of the elements joined together with a copy of the specified delimiter.

Type Parameters:

T - the type of array elements

Parameters:

delimiter - the delimiter that separates each element

objs - the values whose string representations to join together

Returns:

a new string that concatenates the string representations of the elements

join

@Deprecated
public static String join(CharSequence delimiter,
                                      Iterable<?> values)

Deprecated. use UtilPlume.join

Returns a new String composed of the string representations of the elements joined together with a copy of the specified delimiter.

Parameters:

delimiter - the delimiter that separates each element

values - the values whose string representations to join together

Returns:

a new string that concatenates the string representations of the elements

joinLines

@Deprecated
 @SafeVarargs
public static <T> String joinLines(T... a)

Deprecated. use UtilPlume.joinLines

Concatenate the string representations of the objects, placing the system-specific line separator between them.

Type Parameters:

T - the type of array elements

Parameters:

a - array of values to concatenate

Returns:

the concatenation of the string representations of the values, each on its own line

joinLines

@Deprecated
public static String joinLines(Iterable<? extends Object> v)

Deprecated. use UtilPlume.joinLines

Concatenate the string representations of the objects, placing the system-specific line separator between them.

Parameters:

v - list of values to concatenate

Returns:

the concatenation of the string representations of the values, each on its own line

getBooleanSystemProperty

public static boolean getBooleanSystemProperty(String key)

Return true if the system property is set to "true". Return false if the system property is not set or is set to "false". Otherwise, errs.

Parameters:

key - system property to check

Returns:

true if the system property is set to "true". Return false if the system property is not set or is set to "false". Otherwise, errs.

getBooleanSystemProperty

public static boolean getBooleanSystemProperty(String key,
                                               boolean defaultValue)

Return its boolean value if the system property is set. Return defaultValue if the system property is not set. Errs if the system property is set to a non-boolean value.

Parameters:

key - system property to check

defaultValue - value to use if the property is not set

Returns:

the boolean value of key or defaultValue if key is not set

getJreVersion

public static int getJreVersion()

Returns the major JRE version.

This is different from the version passed to the compiler via --release; use getReleaseValue(ProcessingEnvironment) to get that version.

Extract the major version number from the "java.version" system property. Two possible formats are considered. Up to Java 8, from a version string like `1.8.whatever`, this method extracts 8. Since Java 9, from a version string like `11.0.1`, this method extracts 11.

Returns:

the major version number from "java.version"

getReleaseValue

public static @Nullable String getReleaseValue(ProcessingEnvironment env)

Returns the release value passed to the compiler or null if release was not passed.

Parameters:

env - the ProcessingEnvironment

Returns:

the release value or null if none was passed

getToolsJar

public static @Nullable String getToolsJar()

Returns the pathname to the tools.jar file, or null if it does not exist. Returns null on Java 9 and later.

Returns:

the pathname to the tools.jar file, or null

concatenate

public static <T> T[] concatenate(T[] array1,
                                  T... array2)

Concatenates two arrays. Can be invoked varargs-style.

Type Parameters:

T - the type of the array elements

Parameters:

array1 - the first array

array2 - the second array

Returns:

a new array containing the contents of the given arrays, in order

concatenate

public static <T> T[] concatenate(T firstElt,
                                  T[] array,
                                  T lastElt)

Concatenates an element, an array, and an element.

Type Parameters:

T - the type of the array elements

Parameters:

firstElt - the first element

array - the array

lastElt - the last elemeent

Returns:

a new array containing first element, the array, and the last element, in that order

sleep

public static void sleep(long millis)

Like Thread.sleep, but does not throw any exceptions, so it is easier for clients to use. Causes the currently executing thread to sleep (temporarily cease execution) for the specified number of milliseconds.

Parameters:

millis - the length of time to sleep in milliseconds