com.google.appengine.repackaged.com.google.protobuf.TextFormatEscaper Maven / Gradle / Ivy
// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// https://developers.google.com/protocol-buffers/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
package com.google.protobuf;
/**
* Provide text format escaping of proto instances. These ASCII characters are escaped:
*
* ASCII #7 (bell) --> \a
* ASCII #8 (backspace) --> \b
* ASCII #9 (horizontal tab) --> \t
* ASCII #10 (linefeed) --> \n
* ASCII #11 (vertical tab) --> \v
* ASCII #13 (carriage return) --> \r
* ASCII #12 (formfeed) --> \f
* ASCII #34 (apostrophe) --> \'
* ASCII #39 (straight double quote) --> \"
* ASCII #92 (backslash) --> \\
*
* Other printable ASCII characters between 32 and 127 inclusive are output as is, unescaped.
* Other ASCII characters less than 32 and all Unicode characters 128 or greater are
* first encoded as UTF-8, then each byte is escaped individually as a 3-digit octal escape.
*/
final class TextFormatEscaper {
private TextFormatEscaper() {}
private interface ByteSequence {
int size();
byte byteAt(int offset);
}
/**
* Backslash escapes bytes in the format used in protocol buffer text format.
*/
static String escapeBytes(ByteSequence input) {
final StringBuilder builder = new StringBuilder(input.size());
for (int i = 0; i < input.size(); i++) {
byte b = input.byteAt(i);
switch (b) {
case 0x07:
builder.append("\\a");
break;
case '\b':
builder.append("\\b");
break;
case '\f':
builder.append("\\f");
break;
case '\n':
builder.append("\\n");
break;
case '\r':
builder.append("\\r");
break;
case '\t':
builder.append("\\t");
break;
case 0x0b:
builder.append("\\v");
break;
case '\\':
builder.append("\\\\");
break;
case '\'':
builder.append("\\\'");
break;
case '"':
builder.append("\\\"");
break;
default:
// Only ASCII characters between 0x20 (space) and 0x7e (tilde) are
// printable. Other byte values must be escaped.
if (b >= 0x20 && b <= 0x7e) {
builder.append((char) b);
} else {
builder.append('\\');
builder.append((char) ('0' + ((b >>> 6) & 3)));
builder.append((char) ('0' + ((b >>> 3) & 7)));
builder.append((char) ('0' + (b & 7)));
}
break;
}
}
return builder.toString();
}
/**
* Backslash escapes bytes in the format used in protocol buffer text format.
*/
static String escapeBytes(final ByteString input) {
return escapeBytes(
new ByteSequence() {
@Override
public int size() {
return input.size();
}
@Override
public byte byteAt(int offset) {
return input.byteAt(offset);
}
});
}
/** Like {@link #escapeBytes(ByteString)}, but used for byte array. */
static String escapeBytes(final byte[] input) {
return escapeBytes(
new ByteSequence() {
@Override
public int size() {
return input.length;
}
@Override
public byte byteAt(int offset) {
return input[offset];
}
});
}
/**
* Like {@link #escapeBytes(ByteString)}, but escapes a text string.
*/
static String escapeText(String input) {
return escapeBytes(ByteString.copyFromUtf8(input));
}
/** Escape double quotes and backslashes in a String for unicode output of a message. */
static String escapeDoubleQuotesAndBackslashes(String input) {
return input.replace("\\", "\\\\").replace("\"", "\\\"");
}
}