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Core Jackson processing abstractions (aka Streaming API), implementation for JSON
package com.fasterxml.jackson.core.util;
import java.lang.ref.SoftReference;
import com.fasterxml.jackson.core.io.JsonStringEncoder;
/**
* Helper entity used to control access to simple buffer recyling scheme used for
* some encoding, decoding tasks.
*
* @see BufferRecycler
*
* @since 2.9.2
*/
public class BufferRecyclers
{
/**
* System property that is checked to see if recycled buffers (see {@link BufferRecycler})
* should be tracked, for purpose of forcing release of all such buffers, typically
* during major classloading.
*
* @since 2.9.6
*/
public final static String SYSTEM_PROPERTY_TRACK_REUSABLE_BUFFERS
= "com.fasterxml.jackson.core.util.BufferRecyclers.trackReusableBuffers";
/*
/**********************************************************
/* Life-cycle
/**********************************************************
*/
/**
* Flag that indicates whether {@link BufferRecycler} instances should be tracked.
*/
private final static ThreadLocalBufferManager _bufferRecyclerTracker;
static {
boolean trackReusableBuffers = false;
try {
trackReusableBuffers = "true".equals(System.getProperty(SYSTEM_PROPERTY_TRACK_REUSABLE_BUFFERS));
} catch (SecurityException e) { }
_bufferRecyclerTracker = trackReusableBuffers ? ThreadLocalBufferManager.instance() : null;
}
/*
/**********************************************************
/* BufferRecyclers for parsers, generators
/**********************************************************
*/
/**
* This ThreadLocal contains a {@link java.lang.ref.SoftReference}
* to a {@link BufferRecycler} used to provide a low-cost
* buffer recycling between reader and writer instances.
*/
final protected static ThreadLocal> _recyclerRef
= new ThreadLocal>();
/**
* Main accessor to call for accessing possibly recycled {@link BufferRecycler} instance.
*
* @return {@link BufferRecycler} to use
*/
public static BufferRecycler getBufferRecycler()
{
SoftReference ref = _recyclerRef.get();
BufferRecycler br = (ref == null) ? null : ref.get();
if (br == null) {
br = new BufferRecycler();
if (_bufferRecyclerTracker != null) {
ref = _bufferRecyclerTracker.wrapAndTrack(br);
} else {
ref = new SoftReference(br);
}
_recyclerRef.set(ref);
}
return br;
}
/**
* Specialized method that will release all recycled {@link BufferRecycler} if
* (and only if) recycler tracking has been enabled
* (see {@link #SYSTEM_PROPERTY_TRACK_REUSABLE_BUFFERS}).
* This method is usually called on shutdown of the container like Application Server
* to ensure that no references are reachable via {@link ThreadLocal}s as this may cause
* unintentional retention of sizable amounts of memory. It may also be called regularly
* if GC for some reason does not clear up {@link SoftReference}s aggressively enough.
*
* @return Number of buffers released, if tracking enabled (zero or more); -1 if tracking not enabled.
*
* @since 2.9.6
*/
public static int releaseBuffers() {
if (_bufferRecyclerTracker != null) {
return _bufferRecyclerTracker.releaseBuffers();
}
return -1;
}
/*
/**********************************************************************
/* Obsolete things re-introduced in 2.12.5 after accidental direct
/* removal from 2.10.0
/**********************************************************************
*/
/**
* Not to be used any more: call {@link JsonStringEncoder#getInstance()} instead.
*
* @return {@code JsonStringEncoder} instance to use.
*
* @deprecated Since 2.10 (note: was accidentally removed but reintroduced as deprecated
* in 2.12.5, to be removed from 3.0)
*/
@Deprecated
public static JsonStringEncoder getJsonStringEncoder() {
return JsonStringEncoder.getInstance();
}
/**
* Not to be used any more: call {@link JsonStringEncoder#getInstance()} (and then
* {@code encodeAsUTF8()}) instead.
*
* @param text String to encode
* @return String encoded as UTF-8 bytes.
*
* @deprecated Since 2.10 (note: was accidentally removed but reintroduced as deprecated
* in 2.12.5, to be removed from 3.0)
*/
@Deprecated
public static byte[] encodeAsUTF8(String text) {
return JsonStringEncoder.getInstance().encodeAsUTF8(text);
}
/**
* Not to be used any more: call {@link JsonStringEncoder#getInstance()} (and then
* {@code quoteAsString()}) instead.
*
* @param rawText String to quote
*
* @return Quoted text as {@code char[]}
*
* @deprecated Since 2.10 (note: was accidentally removed but reintroduced as deprecated
* in 2.12.5, to be removed from 3.0)
*/
@Deprecated
public static char[] quoteAsJsonText(String rawText) {
return JsonStringEncoder.getInstance().quoteAsString(rawText);
}
/**
* Not to be used any more: call {@link JsonStringEncoder#getInstance()} (and then
* {@code quoteAsString()}) instead.
*
* @param input Textual content to quote
* @param output Builder to append quoted content
*
* @deprecated Since 2.10 (note: was accidentally removed but reintroduced as deprecated
* in 2.12.5, to be removed from 3.0)
*/
@Deprecated
public static void quoteAsJsonText(CharSequence input, StringBuilder output) {
JsonStringEncoder.getInstance().quoteAsString(input, output);
}
/**
* Not to be used any more: call {@link JsonStringEncoder#getInstance()} (and then
* {@code quoteAsUTF8()}) instead.
*
* @param rawText String to quote
*
* @return Quoted text as {@code byte[]}
*
* @deprecated Since 2.10 (note: was accidentally removed but reintroduced as deprecated
* in 2.12.5, to be removed from 3.0)
*/
@Deprecated
public static byte[] quoteAsJsonUTF8(String rawText) {
return JsonStringEncoder.getInstance().quoteAsUTF8(rawText);
}
}