diff options
Diffstat (limited to 'lib/jinterface/java_src/com/ericsson/otp/erlang/OtpOutputStream.java')
| -rw-r--r-- | lib/jinterface/java_src/com/ericsson/otp/erlang/OtpOutputStream.java | 200 |
1 files changed, 169 insertions, 31 deletions
diff --git a/lib/jinterface/java_src/com/ericsson/otp/erlang/OtpOutputStream.java b/lib/jinterface/java_src/com/ericsson/otp/erlang/OtpOutputStream.java index 22ebb4688a..78f47aa32f 100644 --- a/lib/jinterface/java_src/com/ericsson/otp/erlang/OtpOutputStream.java +++ b/lib/jinterface/java_src/com/ericsson/otp/erlang/OtpOutputStream.java @@ -1,7 +1,7 @@ /* * %CopyrightBegin% * - * Copyright Ericsson AB 2000-2011. All Rights Reserved. + * Copyright Ericsson AB 2000-2013. All Rights Reserved. * * The contents of this file are subject to the Erlang Public License, * Version 1.1, (the "License"); you may not use this file except in @@ -26,6 +26,7 @@ import java.math.BigDecimal; import java.math.BigInteger; import java.text.DecimalFormat; import java.util.Arrays; +import java.util.zip.Deflater; /** * Provides a stream for encoding Erlang terms to external format, for @@ -48,6 +49,8 @@ public class OtpOutputStream extends ByteArrayOutputStream { private static final BigDecimal ten = new BigDecimal(10.0); private static final BigDecimal one = new BigDecimal(1.0); + private int fixedSize = Integer.MAX_VALUE; + /** * Create a stream with the default initial size (2048 bytes). */ @@ -101,10 +104,16 @@ public class OtpOutputStream extends ByteArrayOutputStream { * the storage of an <tt>OtpOutputStream</tt> instance. */ public void trimToSize() { - if (super.count < super.buf.length) { - final byte[] tmp = new byte[super.count]; - System.arraycopy(super.buf, 0, tmp, 0, super.count); + resize(super.count); + } + + private void resize(int size) { + if (size < super.buf.length) { + final byte[] tmp = new byte[size]; + System.arraycopy(super.buf, 0, tmp, 0, size); super.buf = tmp; + } else if (size > super.buf.length) { + ensureCapacity(size); } } @@ -116,6 +125,9 @@ public class OtpOutputStream extends ByteArrayOutputStream { * @param minCapacity the desired minimum capacity */ public void ensureCapacity(int minCapacity) { + if (minCapacity > fixedSize) { + throw new IllegalArgumentException("Trying to increase fixed-size buffer"); + } int oldCapacity = super.buf.length; if (minCapacity > oldCapacity) { int newCapacity = (oldCapacity * 3)/2 + 1; @@ -123,6 +135,7 @@ public class OtpOutputStream extends ByteArrayOutputStream { newCapacity = oldCapacity + defaultIncrement; if (newCapacity < minCapacity) newCapacity = minCapacity; + newCapacity = Math.min(fixedSize, newCapacity); // minCapacity is usually close to size, so this is a win: final byte[] tmp = new byte[newCapacity]; System.arraycopy(super.buf, 0, tmp, 0, super.count); @@ -142,19 +155,37 @@ public class OtpOutputStream extends ByteArrayOutputStream { super.buf[super.count++] = b; } - /** - * Write an array of bytes to the stream. - * - * @param buf - * the array of bytes to write. - * + /* (non-Javadoc) + * @see java.io.ByteArrayOutputStream#write(byte[]) */ - @Override public void write(final byte[] buf) { - ensureCapacity(super.count + buf.length); - System.arraycopy(buf, 0, super.buf, super.count, buf.length); - super.count += buf.length; + // don't assume that super.write(byte[]) calls write(buf, 0, buf.length) + write(buf, 0, buf.length); + } + + /* (non-Javadoc) + * @see java.io.ByteArrayOutputStream#write(int) + */ + @Override + public synchronized void write(int b) { + ensureCapacity(super.count + 1); + super.buf[super.count] = (byte) b; + count += 1; + } + + /* (non-Javadoc) + * @see java.io.ByteArrayOutputStream#write(byte[], int, int) + */ + @Override + public synchronized void write(byte[] b, int off, int len) { + if ((off < 0) || (off > b.length) || (len < 0) + || ((off + len) - b.length > 0)) { + throw new IndexOutOfBoundsException(); + } + ensureCapacity(super.count + len); + System.arraycopy(b, off, super.buf, super.count, len); + super.count += len; } /** @@ -343,9 +374,63 @@ public class OtpOutputStream extends ByteArrayOutputStream { * the string to write. */ public void write_atom(final String atom) { - write1(OtpExternal.atomTag); - write2BE(atom.length()); - writeN(atom.getBytes()); + String enc_atom; + byte[] bytes; + boolean isLatin1 = true; + + if (atom.codePointCount(0, atom.length()) <= OtpExternal.maxAtomLength) { + enc_atom = atom; + } + else { + /* + * Throwing an exception would be better I think, + * but truncation seems to be the way it has + * been done in other parts of OTP... + */ + enc_atom = new String(OtpErlangString.stringToCodePoints(atom), + 0, OtpExternal.maxAtomLength); + } + + for (int offset = 0; offset < enc_atom.length();) { + final int cp = enc_atom.codePointAt(offset); + if ((cp & ~0xFF) != 0) { + isLatin1 = false; + break; + } + offset += Character.charCount(cp); + } + try { + if (isLatin1) { + bytes = enc_atom.getBytes("ISO-8859-1"); + write1(OtpExternal.atomTag); + write2BE(bytes.length); + } + else { + bytes = enc_atom.getBytes("UTF-8"); + final int length = bytes.length; + if (length < 256) { + write1(OtpExternal.smallAtomUtf8Tag); + write1(length); + } + else { + write1(OtpExternal.atomUtf8Tag); + write2BE(length); + } + } + writeN(bytes); + } catch (final java.io.UnsupportedEncodingException e) { + /* + * Sigh, why didn't the API designer add an + * OtpErlangEncodeException to these encoding + * functions?!? Instead of changing the API we + * write an invalid atom and let it fail for + * whoever trying to decode this... Sigh, + * again... + */ + write1(OtpExternal.smallAtomUtf8Tag); + write1(2); + write2BE(0xffff); /* Invalid UTF-8 */ + } } /** @@ -765,24 +850,77 @@ public class OtpOutputStream extends ByteArrayOutputStream { /** * Write an arbitrary Erlang term to the stream in compressed format. - * + * * @param o - * the Erlang tem to write. + * the Erlang term to write. */ public void write_compressed(final OtpErlangObject o) { + write_compressed(o, Deflater.DEFAULT_COMPRESSION); + } + + /** + * Write an arbitrary Erlang term to the stream in compressed format. + * + * @param o + * the Erlang term to write. + * @param level + * the compression level (<tt>0..9</tt>) + */ + public void write_compressed(final OtpErlangObject o, int level) { final OtpOutputStream oos = new OtpOutputStream(o); - write1(OtpExternal.compressedTag); - write4BE(oos.size()); - final java.io.FilterOutputStream fos = new java.io.FilterOutputStream( - this); - final java.util.zip.DeflaterOutputStream dos = new java.util.zip.DeflaterOutputStream( - fos); - try { - oos.writeTo(dos); - dos.close(); - } catch (final IOException e) { - throw new java.lang.IllegalArgumentException( - "Intremediate stream failed for Erlang object " + o); + /* + * similar to erts_term_to_binary() in external.c: + * We don't want to compress if compression actually increases the size. + * Since compression uses 5 extra bytes (COMPRESSED tag + size), don't + * compress if the original term is smaller. + */ + if (oos.size() < 5) { + // fast path for small terms + try { + oos.writeTo(this); + // if the term is written as a compressed term, the output + // stream is closed, so we do this here, too + this.close(); + } catch (IOException e) { + throw new java.lang.IllegalArgumentException( + "Intermediate stream failed for Erlang object " + o); + } + } else { + int startCount = super.count; + // we need destCount bytes for an uncompressed term + // -> if compression uses more, use the uncompressed term! + int destCount = startCount + oos.size(); + this.fixedSize = destCount; + Deflater def = new Deflater(level); + final java.util.zip.DeflaterOutputStream dos = new java.util.zip.DeflaterOutputStream( + this, def); + try { + write1(OtpExternal.compressedTag); + write4BE(oos.size()); + oos.writeTo(dos); + dos.close(); // note: closes this, too! + } catch (final IllegalArgumentException e) { + // discard further un-compressed data + // -> if not called, there may be memory leaks! + def.end(); + // could not make the value smaller than originally + // -> reset to starting count, write uncompressed + super.count = startCount; + try { + oos.writeTo(this); + // if the term is written as a compressed term, the output + // stream is closed, so we do this here, too + this.close(); + } catch (IOException e2) { + throw new java.lang.IllegalArgumentException( + "Intermediate stream failed for Erlang object " + o); + } + } catch (final IOException e) { + throw new java.lang.IllegalArgumentException( + "Intermediate stream failed for Erlang object " + o); + } finally { + this.fixedSize = Integer.MAX_VALUE; + } } } |