org.apache.calcite.avatica

Class AvaticaUtils

java.lang.Object

org.apache.calcite.avatica.AvaticaUtils

public class AvaticaUtils
extends Object

Avatica utilities.

Field Summary

Fields

Modifier and Type	Field and Description
private static Map<Class,Class>	BOX
private static MethodHandle	GET_LARGE_MAX_ROWS
private static MethodHandle	GET_LARGE_UPDATE_COUNT
private static MethodHandle	SET_LARGE_MAX_ROWS

Constructor Summary

Constructors

Modifier	Constructor and Description
private	AvaticaUtils()

Method Summary

Methods

Modifier and Type	Method and Description
(package private) static ByteArrayOutputStream	_readFully(InputStream inputStream) Reads the contents of an input stream and returns a ByteArrayOutputStrema.
static Class	box(Class clazz) Returns the boxed class.
static String	camelToUpper(String name) Converts a camelCase name into an upper-case underscore-separated name.
static void	discard(Object o) Does nothing with its argument.
static long	getLargeMaxRows(Statement statement) Invokes Statement#getLargeMaxRows, falling back on Statement.getMaxRows() if the method does not exist (before JDK 1.8) or throws UnsupportedOperationException.
static long	getLargeUpdateCount(Statement statement) Invokes Statement#getLargeUpdateCount, falling back on Statement.getUpdateCount() if the method does not exist (before JDK 1.8) or throws UnsupportedOperationException.
static <T> T	instantiatePlugin(Class<T> pluginClass, String className) Creates an instance of a plugin class.
private static MethodHandle	method(Class returnType, Class targetType, String name, Class... argTypes)
static List<?>	primitiveList(Object array) Adapts a primitive array into a List.
static String	readFully(InputStream inputStream) Reads the contents of an input stream and returns as a string.
static byte[]	readFullyToBytes(InputStream inputStream)
static void	setLargeMaxRows(Statement statement, long n) Invokes Statement#setLargeMaxRows, falling back on Statement.setMaxRows(int) if the method does not exist (before JDK 1.8) or throws UnsupportedOperationException.
static String	toCamelCase(String name) Converts an underscore-separated name into a camelCase name.

Methods inherited from class java.lang.Object

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

Field Detail

BOX

private static final Map<Class,Class> BOX

SET_LARGE_MAX_ROWS

private static final MethodHandle SET_LARGE_MAX_ROWS

GET_LARGE_MAX_ROWS

private static final MethodHandle GET_LARGE_MAX_ROWS

GET_LARGE_UPDATE_COUNT

private static final MethodHandle GET_LARGE_UPDATE_COUNT

Constructor Detail

AvaticaUtils

private AvaticaUtils()

Method Detail

method

private static MethodHandle method(Class returnType,
                  Class targetType,
                  String name,
                  Class... argTypes)

discard

public static void discard(Object o)

Does nothing with its argument. Call this method when you have a value you are not interested in, but you don't want the compiler to warn that you are not using it.

primitiveList

public static List<?> primitiveList(Object array)

Adapts a primitive array into a List. For example, asList(new double[2]) returns a List<Double>.

camelToUpper

public static String camelToUpper(String name)

Converts a camelCase name into an upper-case underscore-separated name. For example, camelToUpper("myJdbcDriver") returns "MY_JDBC_DRIVER".

toCamelCase

public static String toCamelCase(String name)

Converts an underscore-separated name into a camelCase name. For example, uncamel("MY_JDBC_DRIVER") returns "myJdbcDriver".

box

public static Class box(Class clazz)

Returns the boxed class. For example, box(int.class) returns java.lang.Integer.

instantiatePlugin

public static <T> T instantiatePlugin(Class<T> pluginClass,
                      String className)

Creates an instance of a plugin class. First looks for a static member called INSTANCE, then calls a public default constructor.

If className contains a "#" instead looks for a static field.

Type Parameters:

T - Class

Parameters:

pluginClass - Class (or interface) to instantiate

className - Name of implementing class

Returns:

Plugin instance

readFully

public static String readFully(InputStream inputStream)
                        throws IOException

Reads the contents of an input stream and returns as a string.

Throws:

IOException

readFullyToBytes

public static byte[] readFullyToBytes(InputStream inputStream)
                               throws IOException

Throws:

IOException

_readFully

static ByteArrayOutputStream _readFully(InputStream inputStream)
                                 throws IOException

Reads the contents of an input stream and returns a ByteArrayOutputStrema.

Throws:

IOException

setLargeMaxRows

public static void setLargeMaxRows(Statement statement,
                   long n)
                            throws SQLException

Invokes Statement#setLargeMaxRows, falling back on Statement.setMaxRows(int) if the method does not exist (before JDK 1.8) or throws UnsupportedOperationException.

Throws:

SQLException

getLargeMaxRows

public static long getLargeMaxRows(Statement statement)
                            throws SQLException

Invokes Statement#getLargeMaxRows, falling back on Statement.getMaxRows() if the method does not exist (before JDK 1.8) or throws UnsupportedOperationException.

Throws:

SQLException

getLargeUpdateCount

public static long getLargeUpdateCount(Statement statement)
                                throws SQLException

Invokes Statement#getLargeUpdateCount, falling back on Statement.getUpdateCount() if the method does not exist (before JDK 1.8) or throws UnsupportedOperationException.

Throws:

SQLException