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 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, @Nullable Iterable<?> values) Returns a new String composed of the string representations of the elements joined together with a copy of the specified delimiter.
static <T> String	join(CharSequence delimiter, T[] objs) Returns a new String composed of the string representations of the elements joined together with a copy of the specified delimiter.
static String	joinLines(@Nullable Iterable<? extends Object> v) Concatenate the string representations of the objects, placing the system-specific line separator between them.
static <T> String	joinLines(T... a) Concatenate the string representations of the objects, placing the system-specific line separator between them.
static List<String>	readFile(File argFile) Return a list of Strings, one per line of the file.

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

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

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

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

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

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

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

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

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