org.vishia.bridgeC

Class AllocInBlock

java.lang.Object

org.vishia.bridgeC.AllocInBlock

public class AllocInBlock
extends java.lang.Object

This class supports allocation in a given block with equal size. In Java it executes a normal new operation. The feature of using blocks with equal size is a concept of C embedded programming. The class is a counterpart to the Block-Heap-Concept of the CRuntimeJavalike.
All methods to allocate arrays allocByteArray(Object, int) etc. are called with a parent. The parent is any Object, to which the array may associated. The concept in C with blockHeap is: The Object uses a part of a block, the array should use the free spaces in the same block. In Java it is not regarded.
The size-Parameter may be -1. Than in C the rest of memory is used, the size of the returned array depends of the amount of memory. The algorithm using the returned array have to check the size and have to regard several sizes. It is possible that the functionality of a system depends of the amount of memory in a block. It is a possible and useable way in less embedded systems or for some functionalities.
At example see IndexMultiTable: The size of one table depends on this system property. It uses the block heap optimal. But the functionality of IndexMultiTable doesn't depend on it. Using less or greater tables influences only the calculation time in less kind, not the algorithm itself.
If StringBuffer are used in this kind, and the increasing of its size isn't able, a limitation of string size is given.

Field Summary

Fields

Modifier and Type	Field and Description
static int	checkGcBlockFreed
static int	checkGcBlockUsed
static int	checkGcFinished
private static int	defaultBlockUserSize The used size for Java.
private static int	exampleObjectSize In C all methods to allocate arrays may called with an object which should use the same block.

Constructor Summary

Constructors

Constructor and Description
AllocInBlock()

Method Summary

Modifier and Type	Method and Description
static byte[]	allocByteArray(java.lang.Object parent, int size)
static char[]	allocCharArray(java.lang.Object parent, int size)
static double[]	allocDoubleArray(java.lang.Object parent, int size)
static float[]	allocFloatArray(java.lang.Object parent, int size)
static int[]	allocIntArray(java.lang.Object parent, int size)
static long[]	allocLongArray(java.lang.Object parent, int size)
static java.lang.Object[]	allocObjectArray(java.lang.Object parent, int size)
static short[]	allocShortArray(java.lang.Object parent, int size)
static java.lang.StringBuffer	allocStringBuffer(java.lang.Object parent, int size)
static int	garbageCollection_BlockHeapJc(boolean bUserCall) Organizes 1 step for garbage collection.
static int	restSizeBlock(java.lang.Class<?> parent_type, int sizeBlock) Returns the rest of available bytes in the block, which contains parent.
static void	setLogMessageOutput(LogMessage output, int baseNumber)
static void	setRunModeAll() Sets the run mode for all instances of BlockHeapJc.
static int	sizeofPointer() Returns the sizeof a pointer in the C implementation.

Methods inherited from class java.lang.Object

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

Field Detail

defaultBlockUserSize

private static int defaultBlockUserSize

The used size for Java. In C it depends on the size of a block. This size parameter is the number of bytes in a block. In C a block may be 1 kByte, that is 1024 Byte or 0x400 Byte. Because some bytes are need for the block organization, the user gets some less bytes.

exampleObjectSize

private static int exampleObjectSize

In C all methods to allocate arrays may called with an object which should use the same block. This Object has a dedicated size in C. For Java usage

checkGcBlockUsed

public static final int checkGcBlockUsed

See Also:

Constant Field Values

checkGcBlockFreed

public static final int checkGcBlockFreed

See Also:

Constant Field Values

checkGcFinished

public static final int checkGcFinished

See Also:

Constant Field Values

Constructor Detail

AllocInBlock

public AllocInBlock()

Method Detail

restSizeBlock

public static int restSizeBlock(java.lang.Class<?> parent_type,
                                int sizeBlock)

Returns the rest of available bytes in the block, which contains parent. For java using it isn't relevant, the method returns a constant value between 400..2000. The method is relevant for C to calculate some array sizes.

Parameters:

parent - The object which is allocated already in the block. If parent isn't allocated in a block of BlockHeap, this method returns the amount of bytes in a new block.

Returns:

sizeofPointer

public static int sizeofPointer()

Returns the sizeof a pointer in the C implementation. In Java it returns a constant of 4. This method is able to use to calculate the space for pointer arrays (references in Java).

allocByteArray

public static byte[] allocByteArray(java.lang.Object parent,
                                    int size)

allocCharArray

public static char[] allocCharArray(java.lang.Object parent,
                                    int size)

allocStringBuffer

public static java.lang.StringBuffer allocStringBuffer(java.lang.Object parent,
                                                       int size)

allocIntArray

public static int[] allocIntArray(java.lang.Object parent,
                                  int size)

allocShortArray

public static short[] allocShortArray(java.lang.Object parent,
                                      int size)

allocLongArray

public static long[] allocLongArray(java.lang.Object parent,
                                    int size)

allocFloatArray

public static float[] allocFloatArray(java.lang.Object parent,
                                      int size)

allocDoubleArray

public static double[] allocDoubleArray(java.lang.Object parent,
                                        int size)

allocObjectArray

public static java.lang.Object[] allocObjectArray(java.lang.Object parent,
                                                  int size)

setRunModeAll

public static void setRunModeAll()

Sets the run mode for all instances of BlockHeapJc. Any new operation uses the block heap from up to now. In Java it is an empty not necessary instruction, because all actions are done in normal heap. In C this routine have to be implement from the user, because it is situational to all user-defined block heaps.

setLogMessageOutput

public static void setLogMessageOutput(LogMessage output,
                                       int baseNumber)

garbageCollection_BlockHeapJc

public static int garbageCollection_BlockHeapJc(boolean bUserCall)

Organizes 1 step for garbage collection. It is thought for the CRuntimeJavalike - BlockHeap. The garbage collector may be run in a users thread. Therefore it is able to call with this method.

Parameters:

bUserCall - false for the normal garbage collector call.