Package io.github.classgraph.utils

Class JarUtils

java.lang.Object

io.github.classgraph.utils.JarUtils

public class JarUtils
extends Object

Jarfile utilities.

Field Summary

Fields

Modifier and Type	Field	Description
static String[]	SYSTEM_PACKAGE_PATH_PREFIXES	Prefixes of system (JRE) packages, turned into path form (with slashes instead of dots).
static String[]	SYSTEM_PACKAGE_PREFIXES	Prefixes of system (JRE) packages.

Constructor Summary

Constructors

Constructor	Description
JarUtils()

Method Summary

Modifier and Type	Method	Description
static long	countBytesBeforePKMarker(File zipfile)	Count the number of bytes before the characters "PK" in a zipfile.
static ClassLoader	createURLClassLoaderFromPathString(String classpathStr)	Create a custom URLClassLoader from a classpath path string.
static List<String>	getJreJarPaths()
static Set<String>	getJreLibOrExtJars()
static boolean	isInSystemPackageOrModule(String packageOrModuleName)	Return true if the given class name, package name or module name has a system package or module prefix
static boolean	isJREJar(String filePath, ScanSpec scanSpec, LogNode log)
static String	leafName(String path)	Returns the leafname of a path, after first stripping off everything after the first '!', if present.
static void	logJavaInfo(LogNode log)	Log the Java version and the JRE paths that were found.
static String	pathElementsToPathStr(Iterable<?> pathElts)	Get a set of path elements as a string, from an array of objects (e.g.
static String	pathElementsToPathStr(Object... pathElts)	Get a set of path elements as a string, from an array of objects (e.g.
static String[]	smartPathSplit(String pathStr)	Split a path on File.pathSeparator (':' on Linux, ';' on Windows), but also allow for the use of URLs with protocol specifiers, e.g.
static void	stripSFXHeader(File srcZipfile, long sfxHeaderBytes, File destZipfile)	Strip the self-extracting archive header from the beginning of a zipfile.

Methods inherited from class java.lang.Object

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

Field Detail

SYSTEM_PACKAGE_PREFIXES

public static final String[] SYSTEM_PACKAGE_PREFIXES

Prefixes of system (JRE) packages.

SYSTEM_PACKAGE_PATH_PREFIXES

public static final String[] SYSTEM_PACKAGE_PATH_PREFIXES

Prefixes of system (JRE) packages, turned into path form (with slashes instead of dots).

Constructor Detail

JarUtils

public JarUtils()

Method Detail

smartPathSplit

public static String[] smartPathSplit(String pathStr)

Split a path on File.pathSeparator (':' on Linux, ';' on Windows), but also allow for the use of URLs with protocol specifiers, e.g. "http://domain/jar1.jar:http://domain/jar2.jar". This is really not even handled by the JRE, in all likelihood, but it's better to be robust.

Parameters:

pathStr - The path to split.

Returns:

The path element substrings.

createURLClassLoaderFromPathString

public static ClassLoader createURLClassLoaderFromPathString(String classpathStr)

Create a custom URLClassLoader from a classpath path string.

Parameters:

classpathStr - The classpath string.

Returns:

A custom URLClassLoader that can load from the path string.

pathElementsToPathStr

public static String pathElementsToPathStr(Object... pathElts)

Get a set of path elements as a string, from an array of objects (e.g. of String, File or URL type, whose toString() method will be called to get the path component), and return the path as a single string delineated with the standard path separator character.

Parameters:

pathElts - The path elements.

Returns:

The delimited path formed out of the path elements.

pathElementsToPathStr

public static String pathElementsToPathStr(Iterable<?> pathElts)

Get a set of path elements as a string, from an array of objects (e.g. of String, File or URL type, whose toString() method will be called to get the path component), and return the path as a single string delineated with the standard path separator character.

Parameters:

pathElts - The path elements.

Returns:

The delimited path formed out of the path elements, after calling each of their toString() methods.

leafName

public static String leafName(String path)

Returns the leafname of a path, after first stripping off everything after the first '!', if present.

Parameters:

path - A file path.

Returns:

The leafname of the path.

getJreJarPaths

public static List<String> getJreJarPaths()

Returns:

The paths of jars in all JRE/JDK system directories, with any rt.jar listed first.

getJreLibOrExtJars

public static Set<String> getJreLibOrExtJars()

Returns:

The paths for any JRE/JDK "lib/" or "ext/" jars.

isJREJar

public static boolean isJREJar(String filePath,
                               ScanSpec scanSpec,
                               LogNode log)

Parameters:

filePath - A file path.

scanSpec - The ScanSpec.

log - The log.

Returns:

Whether a given jarfile is in a JRE system directory (jre, jre/lib, jre/lib/ext, etc.).

isInSystemPackageOrModule

public static boolean isInSystemPackageOrModule(String packageOrModuleName)

Return true if the given class name, package name or module name has a system package or module prefix

Parameters:

packageOrModuleName - The class, package or module name.

Returns:

Whether this is a system class, package or module.

countBytesBeforePKMarker

public static long countBytesBeforePKMarker(File zipfile)
                                     throws IOException

Count the number of bytes before the characters "PK" in a zipfile.

Parameters:

zipfile - The zipfile.

Returns:

The number of bytes before the characters "PK" in a zipfile. Returns -1 if PK is not found anywhere in the file.

Throws:

IOException - If the file could not be read.

stripSFXHeader

public static void stripSFXHeader(File srcZipfile,
                                  long sfxHeaderBytes,
                                  File destZipfile)
                           throws IOException

Strip the self-extracting archive header from the beginning of a zipfile.

Parameters:

srcZipfile - The source zipfile.

sfxHeaderBytes - The number of bytes of the header to strip.

destZipfile - The destination to save to.

Throws:

IOException - If the operation could not be completed.

logJavaInfo

public static void logJavaInfo(LogNode log)

Log the Java version and the JRE paths that were found.

Parameters:

log - The log.