Package com.mysql.cj.util

Class Util

java.lang.Object
com.mysql.cj.util.Util
public class Util
extends java.lang.Object
Various utility methods for the driver.

  • Constructor Summary

    Constructors 
    Constructor Description
    Util()  

  • Method Summary

    Modifier and Type Method Description
    static java.util.Map<java.lang.Object,​java.lang.Object> calculateDifferences​(java.util.Map<?,​?> map1, java.util.Map<?,​?> map2)  
    static java.lang.Class<?>[] getImplementedInterfaces​(java.lang.Class<?> clazz)
    Retrieves a list with all interfaces implemented by the given class.
    static java.lang.Object getInstance​(java.lang.String className, java.lang.Class<?>[] argTypes, java.lang.Object[] args, ExceptionInterceptor exceptionInterceptor)  
    static java.lang.Object getInstance​(java.lang.String className, java.lang.Class<?>[] argTypes, java.lang.Object[] args, ExceptionInterceptor exceptionInterceptor, java.lang.String errorMessage)  
    static int getJVMUpdateNumber()  
    static int getJVMVersion()  
    static java.lang.String getPackageName​(java.lang.Class<?> clazz)
    Returns the package name of the given class.
    static java.lang.Object handleNewInstance​(java.lang.reflect.Constructor<?> ctor, java.lang.Object[] args, ExceptionInterceptor exceptionInterceptor)
    Handles constructing new instance with the given constructor and wrapping (or not, as required) the exceptions that could possibly be generated
    static boolean interfaceExists​(java.lang.String hostname)
    Does a network interface exist locally with the given hostname?
    static boolean isCommunityEdition​(java.lang.String serverVersion)
    Checks whether the given server version string is a MySQL Community edition
    static boolean isEnterpriseEdition​(java.lang.String serverVersion)
    Checks whether the given server version string is a MySQL Enterprise edition
    static boolean isJdbcInterface​(java.lang.Class<?> clazz)
    Recursively checks for interfaces on the given class to determine if it implements a java.sql, javax.sql or com.mysql.cj.jdbc interface.
    static boolean isJdbcPackage​(java.lang.String packageName)
    Check if the package name is a known JDBC package.
    static boolean isNullOrEmpty​(java.util.List<?> list)  
    static boolean isRunningOnWindows()
    Checks if the JVM is running on Windows Operating System.
    static boolean jvmMeetsMinimum​(int version, int updateNumber)  
    static <T> java.util.List<T> loadClasses​(java.lang.String extensionClassNames, java.lang.String errorMessageKey, ExceptionInterceptor exceptionInterceptor)  
    static int readBlock​(java.io.InputStream i, byte[] b, int length, ExceptionInterceptor exceptionInterceptor)  
    static int readBlock​(java.io.InputStream i, byte[] b, ExceptionInterceptor exceptionInterceptor)  
    static int readFully​(java.io.Reader reader, char[] buf, int length)
    Reads length bytes from reader into buf.
    static long secondsSinceMillis​(long timeInMillis)
    Computes the number of seconds elapsed since the given time in milliseconds.
    static java.lang.String stackTraceToString​(java.lang.Throwable ex)
    Converts a nested exception into a nicer message
    static int truncateAndConvertToInt​(long longValue)
    Converts long to int, truncating to maximum/minimum value if needed.
    static int[] truncateAndConvertToInt​(long[] longArray)
    Converts long[] to int[], truncating to maximum/minimum value if needed.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • Util

      public Util()

  • Method Details

    • getJVMVersion

      public static int getJVMVersion()

    • jvmMeetsMinimum

      public static boolean jvmMeetsMinimum​(int version, int updateNumber)

    • getJVMUpdateNumber

      public static int getJVMUpdateNumber()

    • isCommunityEdition

      public static boolean isCommunityEdition​(java.lang.String serverVersion)
      Checks whether the given server version string is a MySQL Community edition
      Parameters:
      serverVersion - full server version string
      Returns:
      true if version does not contain "enterprise", "commercial" or "advanced"

    • isEnterpriseEdition

      public static boolean isEnterpriseEdition​(java.lang.String serverVersion)
      Checks whether the given server version string is a MySQL Enterprise edition
      Parameters:
      serverVersion - full server version string
      Returns:
      true if version contains "enterprise", "commercial" or "advanced"

    • stackTraceToString

      public static java.lang.String stackTraceToString​(java.lang.Throwable ex)
      Converts a nested exception into a nicer message
      Parameters:
      ex - the exception to expand into a message.
      Returns:
      a message containing the exception, the message (if any), and a stacktrace.

    • getInstance

      public static java.lang.Object getInstance​(java.lang.String className, java.lang.Class<?>[] argTypes, java.lang.Object[] args, ExceptionInterceptor exceptionInterceptor, java.lang.String errorMessage)

    • getInstance

      public static java.lang.Object getInstance​(java.lang.String className, java.lang.Class<?>[] argTypes, java.lang.Object[] args, ExceptionInterceptor exceptionInterceptor)

    • handleNewInstance

      public static java.lang.Object handleNewInstance​(java.lang.reflect.Constructor<?> ctor, java.lang.Object[] args, ExceptionInterceptor exceptionInterceptor)
      Handles constructing new instance with the given constructor and wrapping (or not, as required) the exceptions that could possibly be generated
      Parameters:
      ctor - constructor
      args - arguments for constructor
      exceptionInterceptor - exception interceptor
      Returns:
      object

    • interfaceExists

      public static boolean interfaceExists​(java.lang.String hostname)
      Does a network interface exist locally with the given hostname?
      Parameters:
      hostname - the hostname (or IP address in string form) to check
      Returns:
      true if it exists, false if no, or unable to determine due to VM version support of java.net.NetworkInterface

    • calculateDifferences

      public static java.util.Map<java.lang.Object,​java.lang.Object> calculateDifferences​(java.util.Map<?,​?> map1, java.util.Map<?,​?> map2)

    • loadClasses

      public static <T> java.util.List<T> loadClasses​(java.lang.String extensionClassNames, java.lang.String errorMessageKey, ExceptionInterceptor exceptionInterceptor)

    • isJdbcInterface

      public static boolean isJdbcInterface​(java.lang.Class<?> clazz)
      Recursively checks for interfaces on the given class to determine if it implements a java.sql, javax.sql or com.mysql.cj.jdbc interface.
      Parameters:
      clazz - The class to investigate.
      Returns:
      boolean

    • isJdbcPackage

      public static boolean isJdbcPackage​(java.lang.String packageName)
      Check if the package name is a known JDBC package.
      Parameters:
      packageName - The package name to check.
      Returns:
      boolean

    • getImplementedInterfaces

      public static java.lang.Class<?>[] getImplementedInterfaces​(java.lang.Class<?> clazz)
      Retrieves a list with all interfaces implemented by the given class. If possible gets this information from a cache instead of navigating through the object hierarchy. Results are stored in a cache for future reference.
      Parameters:
      clazz - The class from which the interface list will be retrieved.
      Returns:
      An array with all the interfaces for the given class.

    • secondsSinceMillis

      public static long secondsSinceMillis​(long timeInMillis)
      Computes the number of seconds elapsed since the given time in milliseconds.
      Parameters:
      timeInMillis - The past instant in milliseconds.
      Returns:
      The number of seconds, truncated, elapsed since timeInMillis.

    • truncateAndConvertToInt

      public static int truncateAndConvertToInt​(long longValue)
      Converts long to int, truncating to maximum/minimum value if needed.
      Parameters:
      longValue - long value
      Returns:
      int value

    • truncateAndConvertToInt

      public static int[] truncateAndConvertToInt​(long[] longArray)
      Converts long[] to int[], truncating to maximum/minimum value if needed.
      Parameters:
      longArray - log values
      Returns:
      int values

    • getPackageName

      public static java.lang.String getPackageName​(java.lang.Class<?> clazz)
      Returns the package name of the given class. Using clazz.getPackage().getName() is not an alternative because under some class loaders the method getPackage() just returns null.
      Parameters:
      clazz - the Class from which to get the package name
      Returns:
      the package name

    • isRunningOnWindows

      public static boolean isRunningOnWindows()
      Checks if the JVM is running on Windows Operating System.
      Returns:
      true if currently running on Windows, false otherwise.

    • readFully

      public static int readFully​(java.io.Reader reader, char[] buf, int length) throws java.io.IOException
      Reads length bytes from reader into buf. Blocks until enough input is available
      Parameters:
      reader - Reader
      buf - char array to read into
      length - number of chars to read
      Returns:
      the actual number of chars read
      Throws:
      java.io.IOException - if an error occurs

    • readBlock

      public static final int readBlock​(java.io.InputStream i, byte[] b, ExceptionInterceptor exceptionInterceptor)

    • readBlock

      public static final int readBlock​(java.io.InputStream i, byte[] b, int length, ExceptionInterceptor exceptionInterceptor)

    • isNullOrEmpty

      public static boolean isNullOrEmpty​(java.util.List<?> list)