org.robovm.rt.GC Maven / Gradle / Ivy
package org.robovm.rt;
/**
* Interfaces with the garbage collector
*/
public class GC {
/**
* @return whether this is enabled
*/
public static native boolean getDontExpand();
/**
* Do not expand the heap unless explicitly requested or forced to
* @param value whether this is enabled
*/
public static native void setDontExpand(boolean value);
/**
* @return Get the GC library version.
* The returned value is a constant in the form: ((version_major<<16) | (version_minor<<8) | version_micro).
*/
public static native int getVersion();
/**
* @return Counter incremented per collection. Includes empty GCs at startup.
*/
public static native long getCount();
/**
* Disable garbage collection. Even GC_gcollect calls will be ineffective.
*/
public static native void disable();
/**
* Try to re-enable garbage collection. GC_disable() and GC_enable() calls nest.
* Garbage collection is enabled if the number of calls to both functions is equal.
*/
public static native void enable();
/**
* @return non-zero (TRUE) if and only if garbage collection is disabled (i.e., GC_dont_gc value is non-zero).
* Does not acquire the lock.
*/
public static native boolean isDisabled();
/**
* @return the number of bytes in the heap.
* Excludes collector private data structures.
* Excludes the unmapped memory (returned to the OS).
* Includes empty blocks and fragmentation loss.
* Includes some pages that were allocated but never written.
*/
public static native long getHeapSize();
/**
* @return Return a lower bound on the number of free bytes in the heap (excluding the unmapped memory space).
*/
public static native long getFreeBytes();
/**
* @return Return the size (in bytes) of the unmapped memory (which is returned to the OS but could be remapped
* back by the collector later unless the OS runs out of system/virtual memory).
*/
public static native long getUnmappedBytes();
/**
* @return Return the number of bytes allocated since the last collection.
*/
public static native long getBytesSinceGC();
/**
* @return Return the total number of bytes allocated in this process. Never decreases, except due to wrapping.
*/
public static native long getTotalBytes();
/**
* Perform some garbage collection work, if appropriate. Return 0 if there is no more work to be done.
* Typically performs an amount of work corresponding roughly
* to marking from one page. May do more work if further
* progress requires it, e.g. if incremental collection is
* disabled. It is reasonable to call this in a wait loop
* until it returns 0.
*/
public static native void collectALittle();
/**
* @return the current free space divisor
*/
public static native long getFreeSpaceDivisor();
/**
* We try to make sure that we allocate at least N/GC_free_space_divisor bytes between
* collections, where N is twice the number of traced bytes, plus the number of untraced
* bytes (bytes in "atomic" objects), plus a rough estimate of the root set size.
* N approximates GC tracing work per GC. Initially, GC_free_space_divisor = 3. Increasing its value will use less space
* but more collection time. Decreasing it will appreciably decrease collection time at the expense of space.
*/
public static native void setFreeSpaceDivisor(long value);
/**
* @return The maximum number of GCs attempted before reporting out of memory after heap expansion fails. Initially 0.
*/
public static native long getMaxRetries();
/**
* @param value The maximum number of GCs attempted before reporting out of memory after heap expansion fails. Initially 0.
*/
public static native void setMaxRetries(long value);
public static native long getTimeLimit();
/**
* If incremental collection is enabled, We try to terminate collections after this many milliseconds.
* Not a hard time bound.
* @param value
*/
public static native void setTimeLimit(long value);
}