Package org.apache.flink.runtime.util

Class EnvironmentInformation

  • public class EnvironmentInformation
extends Object
    Utility class that gives access to the execution environment of the JVM, like the executing user, startup options, or the JVM version.

    • Method Detail

      • getVersion

        public static String getVersion()
        Returns the version of the code as String.
        Returns:
        The project version string.

      • getScalaVersion

        public static String getScalaVersion()
        Returns the version of the used Scala compiler as String.
        Returns:
        The scala version string.

      • getBuildTime

        public static Instant getBuildTime()
        Returns:
        The Instant this version of the software was built.

      • getBuildTimeString

        public static String getBuildTimeString()
        Returns:
        The Instant this version of the software was built as a String using the Europe/Berlin timezone.

      • getGitCommitId

        public static String getGitCommitId()
        Returns:
        The last known commit id of this version of the software.

      • getGitCommitIdAbbrev

        public static String getGitCommitIdAbbrev()
        Returns:
        The last known abbreviated commit id of this version of the software.

      • getGitCommitTime

        public static Instant getGitCommitTime()
        Returns:
        The Instant of the last commit of this code.

      • getGitCommitTimeString

        public static String getGitCommitTimeString()
        Returns:
        The Instant of the last commit of this code as a String using the Europe/Berlin timezone.

      • getRevisionInformation

        public static EnvironmentInformation.RevisionInformation getRevisionInformation()
        Returns the code revision (commit and commit date) of Flink, as generated by the Maven builds.
        Returns:
        The code revision.

      • getHadoopUser

        public static String getHadoopUser()
        Gets the name of the user that is running the JVM.
        Returns:
        The name of the user that is running the JVM.

      • getMaxJvmHeapMemory

        public static long getMaxJvmHeapMemory()
        The maximum JVM heap size, in bytes.

        This method uses the -Xmx value of the JVM, if set. If not set, it returns (as a heuristic) 1/4th of the physical memory size.

        Returns:
        The maximum JVM heap size, in bytes.

      • getSizeOfFreeHeapMemoryWithDefrag

        public static long getSizeOfFreeHeapMemoryWithDefrag()
        Gets an estimate of the size of the free heap memory.

        NOTE: This method is heavy-weight. It triggers a garbage collection to reduce fragmentation and get a better estimate at the size of free memory. It is typically more accurate than the plain version getSizeOfFreeHeapMemory().

        Returns:
        An estimate of the size of the free heap memory, in bytes.

      • getSizeOfFreeHeapMemory

        public static long getSizeOfFreeHeapMemory()
        Gets an estimate of the size of the free heap memory. The estimate may vary, depending on the current level of memory fragmentation and the number of dead objects. For a better (but more heavy-weight) estimate, use getSizeOfFreeHeapMemoryWithDefrag().
        Returns:
        An estimate of the size of the free heap memory, in bytes.

      • getJvmVersion

        public static String getJvmVersion()
        Gets the version of the JVM in the form "VM_Name - Vendor - Spec/Version".
        Returns:
        The JVM version.

      • getJvmStartupOptions

        public static String getJvmStartupOptions()
        Gets the system parameters and environment parameters that were passed to the JVM on startup.
        Returns:
        The options passed to the JVM on startup.

      • getJvmStartupOptionsArray

        public static String[] getJvmStartupOptionsArray()
        Gets the system parameters and environment parameters that were passed to the JVM on startup.
        Returns:
        The options passed to the JVM on startup.

      • getTemporaryFileDirectory

        public static String getTemporaryFileDirectory()
        Gets the directory for temporary files, as returned by the JVM system property "java.io.tmpdir".
        Returns:
        The directory for temporary files.

      • getOpenFileHandlesLimit

        public static long getOpenFileHandlesLimit()
        Tries to retrieve the maximum number of open file handles. This method will only work on UNIX-based operating systems with Sun/Oracle Java versions.

        If the number of max open file handles cannot be determined, this method returns -1.

        Returns:
        The limit of open file handles, or -1, if the limit could not be determined.

      • logEnvironmentInfo

        public static void logEnvironmentInfo​(org.slf4j.Logger log,
                                      String componentName,
                                      String[] commandLineArgs)
        Logs information about the environment, like code revision, current user, Java version, and JVM parameters.
        Parameters:
        log - The logger to log the information to.
        componentName - The component name to mention in the log.
        commandLineArgs - The arguments accompanying the starting the component.

      • getHadoopVersionString

        public static String getHadoopVersionString()