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/*
* Copyright (C) 2014-2022 Philip Helger (www.helger.com)
* philip[at]helger[dot]com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.helger.commons.lang;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.Writer;
import java.nio.charset.StandardCharsets;
import java.time.ZonedDateTime;
import java.util.Map;
import java.util.Properties;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import javax.annotation.WillNotClose;
import com.helger.commons.collection.impl.CommonsLinkedHashMap;
import com.helger.commons.io.stream.NonBlockingBufferedWriter;
import com.helger.commons.io.stream.StreamHelper;
import com.helger.commons.string.StringHelper;
import com.helger.commons.system.ENewLineMode;
/**
* The NonBlockingProperties class represents a persistent set of
* properties. The NonBlockingProperties can be saved to a stream
* or loaded from a stream. Each key and its corresponding value in the property
* list is a string.
*
* A property list can contain another property list as its "defaults"; this
* second property list is searched if the property key is not found in the
* original property list.
*
* Because NonBlockingProperties inherits from
* CommonsTreeMap , the put and putAll
* methods can be applied to a NonBlockingProperties object. Their
* use is strongly discouraged as they allow the caller to insert entries whose
* keys or values are not Strings. The setProperty
* method should be used instead. If the store or save
* method is called on a "compromised" NonBlockingProperties object
* that contains a non- String key or value, the call will fail.
* Similarly, the call to the propertyNames or list
* method will fail if it is called on a "compromised"
* NonBlockingProperties object that contains a non-
* String key.
*
* The {@link #load(java.io.Reader) load(Reader)} /
* {@link #store(java.io.Writer, java.lang.String) store(Writer, String)}
* methods load and store properties from and to a character based stream in a
* simple line-oriented format specified below. The
* {@link #load(java.io.InputStream) load(InputStream)} /
* {@link #store(java.io.OutputStream, java.lang.String) store(OutputStream,
* String)} methods work the same way as the load(Reader)/store(Writer, String)
* pair, except the input/output stream is encoded in ISO 8859-1 character
* encoding. Characters that cannot be directly represented in this encoding can
* be written using
* Unicode escapes ; only a single 'u' character is allowed in an escape
* sequence. The native2ascii tool can be used to convert property files to and
* from other character encodings.
*
* @author Arthur van Hoff
* @author Michael McCloskey
* @author Xueming Shen
* @author Philip Helger
*/
public class NonBlockingProperties extends CommonsLinkedHashMap
{
// No logger here!
/**
* A property list that contains default values for any keys not found in this
* property list.
*/
protected NonBlockingProperties m_aDefaults;
/**
* Creates an empty property list with no default values.
*/
public NonBlockingProperties ()
{
this ((NonBlockingProperties) null);
}
/**
* Creates an empty property list with the specified defaults.
*
* @param aDefaults
* the defaults.
*/
public NonBlockingProperties (@Nullable final NonBlockingProperties aDefaults)
{
m_aDefaults = aDefaults;
}
/**
* @return The default properties as passed in the constructor. May be
* null.
*/
@Nullable
public NonBlockingProperties getDefaults ()
{
return m_aDefaults;
}
/**
* Calls the Hashtable method put. Provided for
* parallelism with the getProperty method. Enforces use of
* strings for property keys and values. The value returned is the result of
* the Hashtable call to put.
*
* @param sKey
* the key to be placed into this property list.
* @param sValue
* the value corresponding to key.
* @return the previous value of the specified key in this property list, or
* null if it did not have one.
* @see #getProperty
* @since 1.2
*/
@Nullable
public String setProperty (final String sKey, final String sValue)
{
return put (sKey, sValue);
}
/**
* Reads a property list (key and element pairs) from the input character
* stream in a simple line-oriented format.
*
* Properties are processed in terms of lines. There are two kinds of line,
* natural lines and logical lines. A natural line is defined as
* a line of characters that is terminated either by a set of line terminator
* characters (\n or \r or \r\n) or by
* the end of the stream. A natural line may be either a blank line, a comment
* line, or hold all or some of a key-element pair. A logical line holds all
* the data of a key-element pair, which may be spread out across several
* adjacent natural lines by escaping the line terminator sequence with a
* backslash character \. Note that a comment line cannot be
* extended in this manner; every natural line that is a comment must have its
* own comment indicator, as described below. Lines are read from input until
* the end of the stream is reached.
*
*
* A natural line that contains only white space characters is considered
* blank and is ignored. A comment line has an ASCII '#' or
* '!' as its first non-white space character; comment lines are
* also ignored and do not encode key-element information. In addition to line
* terminators, this format considers the characters space (' ',
* '\u0020'), tab ('\t',
* '\u0009'), and form feed ('\f',
* '\u000C') to be white space.
*
*
* If a logical line is spread across several natural lines, the backslash
* escaping the line terminator sequence, the line terminator sequence, and
* any white space at the start of the following line have no affect on the
* key or element values. The remainder of the discussion of key and element
* parsing (when loading) will assume all the characters constituting the key
* and element appear on a single natural line after line continuation
* characters have been removed. Note that it is not sufficient to only
* examine the character preceding a line terminator sequence to decide if the
* line terminator is escaped; there must be an odd number of contiguous
* backslashes for the line terminator to be escaped. Since the input is
* processed from left to right, a non-zero even number of 2n
* contiguous backslashes before a line terminator (or elsewhere) encodes
* n backslashes after escape processing.
*
*
* The key contains all of the characters in the line starting with the first
* non-white space character and up to, but not including, the first unescaped
* '=', ':', or white space character other than a
* line terminator. All of these key termination characters may be included in
* the key by escaping them with a preceding backslash character; for example,
*
*
* \:\=
*
*
* would be the two-character key ":=". Line terminator
* characters can be included using \r and \n escape
* sequences. Any white space after the key is skipped; if the first non-white
* space character after the key is '=' or ':', then
* it is ignored and any white space characters after it are also skipped. All
* remaining characters on the line become part of the associated element
* string; if there are no remaining characters, the element is the empty
* string "". Once the raw character sequences
* constituting the key and element are identified, escape processing is
* performed as described above.
*
*
* As an example, each of the following three lines specifies the key
* "Truth" and the associated element value "Beauty"
* :
*
*
*
* Truth = Beauty
* Truth:Beauty
* Truth :Beauty
*
*
* As another example, the following three lines specify a single property:
*
*
*
* fruits apple, banana, pear, \
* cantaloupe, watermelon, \
* kiwi, mango
*
*
* The key is "fruits" and the associated element is:
*
*
*
* "apple, banana, pear, cantaloupe, watermelon, kiwi, mango"
*
*
* Note that a space appears before each \ so that a space will
* appear after each comma in the final result; the \, line
* terminator, and leading white space on the continuation line are merely
* discarded and are not replaced by one or more other characters.
*
*
* As a third example, the line:
*
*
*
* cheeses
*
*
* specifies that the key is "cheeses" and the associated element
* is the empty string "".
*
*
* Characters in keys and elements can be represented in escape sequences
* similar to those used for character and string literals (see
* §3.3 and §3.10.6 of the Java Language Specification). The
* differences from the character escape sequences and Unicode escapes used
* for characters and strings are:
*
*
* - Octal escapes are not recognized.
*
- The character sequence
\b does not represent a
* backspace character.
* - The method does not treat a backslash character,
\, before
* a non-valid escape character as an error; the backslash is silently
* dropped. For example, in a Java string the sequence "\z" would
* cause a compile time error. In contrast, this method silently drops the
* backslash. Therefore, this method treats the two character sequence
* "\b" as equivalent to the single character 'b'.
* - Escapes are not necessary for single and double quotes; however, by the
* rule above, single and double quote characters preceded by a backslash
* still yield single and double quote characters, respectively.
*
- Only a single 'u' character is allowed in a Unicode escape sequence.
*
*
* The specified stream remains open after this method returns.
*
*
* @param aReader
* the input character stream.
* @throws IOException
* if an error occurred when reading from the input stream.
* @throws IllegalArgumentException
* if a malformed Unicode escape appears in the input.
* @since 1.6
*/
public void load (@WillNotClose final Reader aReader) throws IOException
{
_load (new LineReader (aReader));
}
/**
* Reads a property list (key and element pairs) from the input byte stream.
* The input stream is in a simple line-oriented format as specified in
* {@link #load(java.io.Reader) load(Reader)} and is assumed to use the ISO
* 8859-1 character encoding; that is each byte is one Latin1 character.
* Characters not in Latin1, and certain special characters, are represented
* in keys and elements using
* Unicode escapes.
*
* The specified stream remains open after this method returns.
*
* @param aIS
* the input stream.
* @exception IOException
* if an error occurred when reading from the input stream.
* @throws IllegalArgumentException
* if the input stream contains a malformed Unicode escape sequence.
* @since 1.2
*/
public void load (@WillNotClose final InputStream aIS) throws IOException
{
_load (new LineReader (aIS));
}
private void _load (@WillNotClose final LineReader aLineReader) throws IOException
{
final char [] aBuf = new char [1024];
int nLimit;
while ((nLimit = aLineReader.readLine ()) >= 0)
{
char c = 0;
int nKeyLen = 0;
int nValueStart = nLimit;
boolean bHasSep = false;
// System.out.println("line=<" + new String(lineBuf, 0, limit) + ">");
boolean bPrecedingBackslash = false;
while (nKeyLen < nLimit)
{
c = aLineReader.m_aLineBuf[nKeyLen];
// need check if escaped.
if ((c == '=' || c == ':') && !bPrecedingBackslash)
{
nValueStart = nKeyLen + 1;
bHasSep = true;
break;
}
else
if ((c == ' ' || c == '\t' || c == '\f') && !bPrecedingBackslash)
{
nValueStart = nKeyLen + 1;
break;
}
if (c == '\\')
bPrecedingBackslash = !bPrecedingBackslash;
else
bPrecedingBackslash = false;
nKeyLen++;
}
while (nValueStart < nLimit)
{
c = aLineReader.m_aLineBuf[nValueStart];
if (c != ' ' && c != '\t' && c != '\f')
{
if (!bHasSep && (c == '=' || c == ':'))
bHasSep = true;
else
break;
}
nValueStart++;
}
final String sKey = _loadConvert (aLineReader.m_aLineBuf, 0, nKeyLen, aBuf);
final String value = _loadConvert (aLineReader.m_aLineBuf, nValueStart, nLimit - nValueStart, aBuf);
put (sKey, value);
}
}
/*
* Read in a "logical line" from an InputStream/Reader, skip all comment and
* blank lines and filter out those leading whitespace characters ( , and )
* from the beginning of a "natural line". Method returns the char length of
* the "logical line" and stores the line in "lineBuf".
*/
static class LineReader
{
private byte [] m_aInByteBuf;
private char [] m_aInCharBuf;
private char [] m_aLineBuf = new char [1024];
private int m_nInLimit = 0;
private int m_nInOff = 0;
private InputStream m_aIS;
private Reader m_aReader;
public LineReader (final InputStream aIS)
{
m_aIS = aIS;
m_aInByteBuf = new byte [8192];
}
public LineReader (final Reader aReader)
{
m_aReader = aReader;
m_aInCharBuf = new char [8192];
}
protected int readLine () throws IOException
{
int nLen = 0;
char c = 0;
boolean bSkipWhiteSpace = true;
boolean bIsCommentLine = false;
boolean bIsNewLine = true;
boolean bAppendedLineBegin = false;
boolean bPrecedingBackslash = false;
boolean bSkipLF = false;
while (true)
{
if (m_nInOff >= m_nInLimit)
{
m_nInLimit = (m_aIS == null) ? m_aReader.read (m_aInCharBuf) : m_aIS.read (m_aInByteBuf);
m_nInOff = 0;
if (m_nInLimit <= 0)
{
if (nLen == 0 || bIsCommentLine)
return -1;
return nLen;
}
}
if (m_aIS != null)
{
// The line below is equivalent to calling a
// ISO8859-1 decoder.
c = (char) (0xff & m_aInByteBuf[m_nInOff++]);
}
else
{
c = m_aInCharBuf[m_nInOff++];
}
if (bSkipLF)
{
bSkipLF = false;
if (c == '\n')
continue;
}
if (bSkipWhiteSpace)
{
if (c == ' ' || c == '\t' || c == '\f')
continue;
if (!bAppendedLineBegin && (c == '\r' || c == '\n'))
continue;
bSkipWhiteSpace = false;
bAppendedLineBegin = false;
}
if (bIsNewLine)
{
bIsNewLine = false;
if (c == '#' || c == '!')
{
bIsCommentLine = true;
continue;
}
}
if (c != '\n' && c != '\r')
{
m_aLineBuf[nLen++] = c;
if (nLen == m_aLineBuf.length)
{
int newLength = m_aLineBuf.length * 2;
if (newLength < 0)
{
newLength = Integer.MAX_VALUE;
}
final char [] buf = new char [newLength];
System.arraycopy (m_aLineBuf, 0, buf, 0, m_aLineBuf.length);
m_aLineBuf = buf;
}
// flip the preceding backslash flag
if (c == '\\')
bPrecedingBackslash = !bPrecedingBackslash;
else
bPrecedingBackslash = false;
}
else
{
// reached EOL
if (bIsCommentLine || nLen == 0)
{
bIsCommentLine = false;
bIsNewLine = true;
bSkipWhiteSpace = true;
nLen = 0;
continue;
}
if (m_nInOff >= m_nInLimit)
{
m_nInLimit = m_aIS == null ? m_aReader.read (m_aInCharBuf) : m_aIS.read (m_aInByteBuf);
m_nInOff = 0;
if (m_nInLimit <= 0)
return nLen;
}
if (bPrecedingBackslash)
{
nLen -= 1;
// skip the leading whitespace characters in following line
bSkipWhiteSpace = true;
bAppendedLineBegin = true;
bPrecedingBackslash = false;
if (c == '\r')
bSkipLF = true;
}
else
return nLen;
}
}
}
}
/*
* Converts encoded \uxxxx to unicode chars and changes special saved
* chars to their original forms
*/
@Nonnull
private static String _loadConvert (@Nonnull final char [] aIn, final int nOfs, final int nLen, @Nonnull final char [] aConvBuf)
{
int nCurOfs = nOfs;
char [] aOut;
if (aConvBuf.length < nLen)
{
int nNewLen = nLen * 2;
if (nNewLen < 0)
nNewLen = Integer.MAX_VALUE;
aOut = new char [nNewLen];
}
else
aOut = aConvBuf;
char aChar;
int nOutLen = 0;
final int nEndOfs = nCurOfs + nLen;
while (nCurOfs < nEndOfs)
{
aChar = aIn[nCurOfs++];
if (aChar == '\\')
{
aChar = aIn[nCurOfs++];
if (aChar == 'u')
{
// Read the xxxx
int nValue = 0;
for (int i = 0; i < 4; i++)
{
aChar = aIn[nCurOfs++];
switch (aChar)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
nValue = (nValue << 4) + aChar - '0';
break;
case 'a':
case 'b':
case 'c':
case 'd':
case 'e':
case 'f':
nValue = (nValue << 4) + 10 + aChar - 'a';
break;
case 'A':
case 'B':
case 'C':
case 'D':
case 'E':
case 'F':
nValue = (nValue << 4) + 10 + aChar - 'A';
break;
default:
throw new IllegalArgumentException ("Malformed \\uxxxx encoding.");
}
}
aOut[nOutLen++] = (char) nValue;
}
else
{
if (aChar == 't')
aChar = '\t';
else
if (aChar == 'r')
aChar = '\r';
else
if (aChar == 'n')
aChar = '\n';
else
if (aChar == 'f')
aChar = '\f';
aOut[nOutLen++] = aChar;
}
}
else
{
aOut[nOutLen++] = aChar;
}
}
return new String (aOut, 0, nOutLen);
}
/*
* Converts unicodes to encoded \uxxxx and escapes special characters with
* a preceding slash
*/
@Nonnull
private static String _saveConvert (final String sStr, final boolean bEscapeSpace, final boolean bEscapeUnicode)
{
final int nLen = sStr.length ();
int nBufLen = nLen * 2;
if (nBufLen < 0)
nBufLen = Integer.MAX_VALUE;
final StringBuilder aSB = new StringBuilder (nBufLen);
for (int x = 0; x < nLen; x++)
{
final char aChar = sStr.charAt (x);
// Handle common case first, selecting largest block that
// avoids the specials below
// 61 == '='
if (aChar > 61 && aChar < 127)
{
if (aChar == '\\')
{
aSB.append ('\\').append ('\\');
continue;
}
aSB.append (aChar);
continue;
}
switch (aChar)
{
case ' ':
if (x == 0 || bEscapeSpace)
aSB.append ('\\');
aSB.append (' ');
break;
case '\t':
aSB.append ('\\').append ('t');
break;
case '\n':
aSB.append ('\\').append ('n');
break;
case '\r':
aSB.append ('\\').append ('r');
break;
case '\f':
aSB.append ('\\').append ('f');
break;
case '=':
case ':':
case '#':
case '!':
aSB.append ('\\').append (aChar);
break;
default:
if ((aChar < 0x0020 || aChar > 0x007e) && bEscapeUnicode)
{
aSB.append ('\\')
.append ('u')
.append (StringHelper.getHexChar ((aChar >> 12) & 0xF))
.append (StringHelper.getHexChar ((aChar >> 8) & 0xF))
.append (StringHelper.getHexChar ((aChar >> 4) & 0xF))
.append (StringHelper.getHexChar (aChar & 0xF));
}
else
{
aSB.append (aChar);
}
}
}
return aSB.toString ();
}
private static void _writeComments (@Nonnull @WillNotClose final Writer aWriter, @Nonnull final String sComments) throws IOException
{
aWriter.write ("#");
final int nLen = sComments.length ();
int nCurrent = 0;
int nLast = 0;
final char [] uu = new char [6];
uu[0] = '\\';
uu[1] = 'u';
while (nCurrent < nLen)
{
final char c = sComments.charAt (nCurrent);
if (c > '\u00ff' || c == '\n' || c == '\r')
{
if (nLast != nCurrent)
aWriter.write (sComments.substring (nLast, nCurrent));
if (c > '\u00ff')
{
uu[2] = StringHelper.getHexChar ((c >> 12) & 0xf);
uu[3] = StringHelper.getHexChar ((c >> 8) & 0xf);
uu[4] = StringHelper.getHexChar ((c >> 4) & 0xf);
uu[5] = StringHelper.getHexChar (c & 0xf);
aWriter.write (uu);
}
else
{
aWriter.write (ENewLineMode.DEFAULT.getText ());
if (c == '\r' && nCurrent != nLen - 1 && sComments.charAt (nCurrent + 1) == '\n')
nCurrent++;
if (nCurrent == nLen - 1 || (sComments.charAt (nCurrent + 1) != '#' && sComments.charAt (nCurrent + 1) != '!'))
aWriter.write ("#");
}
nLast = nCurrent + 1;
}
nCurrent++;
}
if (nLast != nCurrent)
aWriter.write (sComments.substring (nLast, nCurrent));
aWriter.write (ENewLineMode.DEFAULT.getText ());
}
/**
* Writes this property list (key and element pairs) in this
* Properties table to the output character stream in a format
* suitable for using the {@link #load(java.io.Reader) load(Reader)} method.
*
* Properties from the defaults table of this Properties table
* (if any) are not written out by this method.
*
* If the comments argument is not null, then an ASCII #
* character, the comments string, and a line separator are first written to
* the output stream. Thus, the comments can serve as an
* identifying comment. Any one of a line feed ('\n'), a carriage return
* ('\r'), or a carriage return followed immediately by a line feed in
* comments is replaced by a line separator generated by the
* Writer and if the next character in comments is not character
* # or character ! then an ASCII # is
* written out after that line separator.
*
* Next, a comment line is always written, consisting of an ASCII
* # character, the current date and time (as if produced by the
* toString method of Date for the current time),
* and a line separator as generated by the Writer.
*
* Then every entry in this Properties table is written out, one
* per line. For each entry the key string is written, then an ASCII
* =, then the associated element string. For the key, all space
* characters are written with a preceding \ character. For the
* element, leading space characters, but not embedded or trailing space
* characters, are written with a preceding \ character. The key
* and element characters #, !, =, and
* : are written with a preceding backslash to ensure that they
* are properly loaded.
*
* After the entries have been written, the output stream is flushed. The
* output stream remains open after this method returns.
*
*
* @param aWriter
* an output character stream writer.
* @param sComments
* a description of the property list.
* @exception IOException
* if writing this property list to the specified output stream
* throws an IOException.
* @exception ClassCastException
* if this Properties object contains any keys or
* values that are not Strings.
* @exception NullPointerException
* if writer is null.
* @since 1.6
*/
public void store (@Nonnull @WillNotClose final Writer aWriter, @Nullable final String sComments) throws IOException
{
_store (StreamHelper.getBuffered (aWriter), sComments, false);
}
/**
* Writes this property list (key and element pairs) in this
* Properties table to the output stream in a format suitable for
* loading into a Properties table using the
* {@link #load(InputStream) load(InputStream)} method.
*
* Properties from the defaults table of this Properties table
* (if any) are not written out by this method.
*
* This method outputs the comments, properties keys and values in the same
* format as specified in {@link #store(java.io.Writer, java.lang.String)
* store(Writer)}, with the following differences:
*
* - The stream is written using the ISO 8859-1 character encoding.
*
- Characters not in Latin-1 in the comments are written as
*
\uxxxx for their appropriate unicode hexadecimal
* value xxxx.
* - Characters less than
\u0020 and characters greater
* than \u007E in property keys or values are written as
* \uxxxx for the appropriate hexadecimal value
* xxxx.
*
*
* After the entries have been written, the output stream is flushed. The
* output stream remains open after this method returns.
*
*
* @param aOS
* an output stream.
* @param sComments
* a description of the property list.
* @exception IOException
* if writing this property list to the specified output stream
* throws an IOException.
* @exception ClassCastException
* if this Properties object contains any keys or
* values that are not Strings.
* @exception NullPointerException
* if out is null.
* @since 1.2
*/
public void store (@Nonnull @WillNotClose final OutputStream aOS, @Nullable final String sComments) throws IOException
{
_store (new NonBlockingBufferedWriter (new OutputStreamWriter (aOS, StandardCharsets.ISO_8859_1)), sComments, true);
}
private void _store (@Nonnull @WillNotClose final Writer aWriter,
@Nullable final String sComments,
final boolean bEscapeUnicode) throws IOException
{
if (sComments != null)
_writeComments (aWriter, sComments);
final String sNewLine = ENewLineMode.DEFAULT.getText ();
aWriter.write ("#" + ZonedDateTime.now ().toString () + sNewLine);
for (final Map.Entry aEntry : entrySet ())
{
String sKey = aEntry.getKey ();
sKey = _saveConvert (sKey, true, bEscapeUnicode);
String sValue = aEntry.getValue ();
/*
* No need to escape embedded and trailing spaces for value, hence pass
* false to flag.
*/
sValue = sValue == null ? "" : _saveConvert (sValue, false, bEscapeUnicode);
aWriter.write (sKey);
aWriter.write ('=');
aWriter.write (sValue);
aWriter.write (sNewLine);
}
aWriter.flush ();
}
/**
* Searches for the property with the specified key in this property list. If
* the key is not found in this property list, the default property list, and
* its defaults, recursively, are then checked. The method returns
* null if the property is not found.
*
* @param sKey
* the property key.
* @return the value in this property list with the specified key value.
* @see #setProperty
*/
@Nullable
public String getProperty (@Nullable final String sKey)
{
final String sValue = super.get (sKey);
return sValue == null && m_aDefaults != null ? m_aDefaults.getProperty (sKey) : sValue;
}
/**
* Searches for the property with the specified key in this property list. If
* the key is not found in this property list, the default property list, and
* its defaults, recursively, are then checked. The method returns the default
* value argument if the property is not found.
*
* @param sKey
* the map key.
* @param sDefaultValue
* a default value.
* @return the value in this property list with the specified key value.
* @see #setProperty
*/
@Nullable
public String getProperty (@Nullable final String sKey, @Nullable final String sDefaultValue)
{
final String sValue = getProperty (sKey);
return sValue == null ? sDefaultValue : sValue;
}
@Override
public boolean equals (final Object o)
{
if (o == this)
return true;
if (o == null || !getClass ().equals (o.getClass ()))
return false;
return super.equals (o);
}
@Override
public int hashCode ()
{
return super.hashCode ();
}
/**
* Create {@link NonBlockingProperties} from an existing {@link Properties}
* object.
*
* @param aProperties
* Source properties. May be null.
* @return The newly created {@link NonBlockingProperties}. Never
* null.
*/
@Nonnull
public static NonBlockingProperties create (@Nullable final Map aProperties)
{
final NonBlockingProperties ret = new NonBlockingProperties ();
if (aProperties != null)
for (final Map.Entry aEntry : aProperties.entrySet ())
ret.put ((String) aEntry.getKey (), (String) aEntry.getValue ());
return ret;
}
}