org.apache.commons.configuration2.PropertiesConfiguration Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of commons-configuration2 Show documentation
Show all versions of commons-configuration2 Show documentation
Tools to assist in the reading of configuration/preferences files in
various formats
The newest version!
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.commons.configuration2;
import java.io.FileNotFoundException;
import java.io.FilterWriter;
import java.io.IOException;
import java.io.LineNumberReader;
import java.io.Reader;
import java.io.Writer;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Deque;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.commons.configuration2.convert.ListDelimiterHandler;
import org.apache.commons.configuration2.convert.ValueTransformer;
import org.apache.commons.configuration2.event.ConfigurationEvent;
import org.apache.commons.configuration2.ex.ConfigurationException;
import org.apache.commons.configuration2.ex.ConfigurationRuntimeException;
import org.apache.commons.configuration2.io.FileHandler;
import org.apache.commons.configuration2.io.FileLocator;
import org.apache.commons.configuration2.io.FileLocatorAware;
import org.apache.commons.configuration2.io.FileLocatorUtils;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.text.StringEscapeUtils;
import org.apache.commons.text.translate.AggregateTranslator;
import org.apache.commons.text.translate.CharSequenceTranslator;
import org.apache.commons.text.translate.EntityArrays;
import org.apache.commons.text.translate.LookupTranslator;
import org.apache.commons.text.translate.UnicodeEscaper;
/**
* This is the "classic" Properties loader which loads the values from a single or multiple files (which can be chained
* with "include =". All given path references are either absolute or relative to the file name supplied in the
* constructor.
*
* In this class, empty PropertyConfigurations can be built, properties added and later saved. include statements are
* (obviously) not supported if you don't construct a PropertyConfiguration from a file.
*
*
* The properties file syntax is explained here, basically it follows the syntax of the stream parsed by
* {@link java.util.Properties#load} and adds several useful extensions:
*
*
* - Each property has the syntax {@code key <separator> value}. The separators accepted are {@code '='},
* {@code ':'} and any white space character. Examples:
*
*
* key1 = value1
* key2 : value2
* key3 value3
*
*
*
* - The key may use any character, separators must be escaped:
*
*
* key\:foo = bar
*
*
*
* - value may be separated on different lines if a backslash is placed at the end of the line that continues
* below.
* - The list delimiter facilities provided by {@link AbstractConfiguration} are supported, too. If an appropriate
* {@link ListDelimiterHandler} is set (for instance a
* {@link org.apache.commons.configuration2.convert.DefaultListDelimiterHandler D efaultListDelimiterHandler} object
* configured with a comma as delimiter character), value can contain value delimiters and will then be
* interpreted as a list of tokens. So the following property definition
*
*
* key = This property, has multiple, values
*
*
* will result in a property with three values. You can change the handling of delimiters using the
* {@link AbstractConfiguration#setListDelimiterHandler(ListDelimiterHandler)} method. Per default, list splitting is
* disabled.
* - Commas in each token are escaped placing a backslash right before the comma.
* - If a key is used more than once, the values are appended like if they were on the same line separated with
* commas. Note: When the configuration file is written back to disk the associated
* {@link PropertiesConfigurationLayout} object (see below) will try to preserve as much of the original format as
* possible, i.e. properties with multiple values defined on a single line will also be written back on a single line,
* and multiple occurrences of a single key will be written on multiple lines. If the {@code addProperty()} method was
* called multiple times for adding multiple values to a property, these properties will per default be written on
* multiple lines in the output file, too. Some options of the {@code PropertiesConfigurationLayout} class have
* influence on that behavior.
* - Blank lines and lines starting with character '#' or '!' are skipped.
* - If a property is named "include" (or whatever is defined by setInclude() and getInclude() and the value of that
* property is the full path to a file on disk, that file will be included into the configuration. You can also pull in
* files relative to the parent configuration file. So if you have something like the following:
*
* include = additional.properties
*
* Then "additional.properties" is expected to be in the same directory as the parent configuration file.
*
* The properties in the included file are added to the parent configuration, they do not replace existing properties
* with the same key.
*
*
* - You can define custom error handling for the special key {@code "include"} by using
* {@link #setIncludeListener(ConfigurationConsumer)}.
*
*
*
* Here is an example of a valid extended properties file:
*
*
*
* # lines starting with # are comments
*
* # This is the simplest property
* key = value
*
* # A long property may be separated on multiple lines
* longvalue = aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa \
* aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
*
* # This is a property with many tokens
* tokens_on_a_line = first token, second token
*
* # This sequence generates exactly the same result
* tokens_on_multiple_lines = first token
* tokens_on_multiple_lines = second token
*
* # commas may be escaped in tokens
* commas.escaped = Hi\, what'up?
*
* # properties can reference other properties
* base.prop = /base
* first.prop = ${base.prop}/first
* second.prop = ${first.prop}/second
*
*
*
* A {@code PropertiesConfiguration} object is associated with an instance of the {@link PropertiesConfigurationLayout}
* class, which is responsible for storing the layout of the parsed properties file (i.e. empty lines, comments, and
* such things). The {@code getLayout()} method can be used to obtain this layout object. With {@code setLayout()} a new
* layout object can be set. This should be done before a properties file was loaded.
*
* Like other {@code Configuration} implementations, this class uses a {@code Synchronizer} object to control concurrent
* access. By choosing a suitable implementation of the {@code Synchronizer} interface, an instance can be made
* thread-safe or not. Note that access to most of the properties typically set through a builder is not protected by
* the {@code Synchronizer}. The intended usage is that these properties are set once at construction time through the
* builder and after that remain constant. If you wish to change such properties during life time of an instance, you
* have to use the {@code lock()} and {@code unlock()} methods manually to ensure that other threads see your changes.
*
* As this class extends {@link AbstractConfiguration}, all basic features like variable interpolation, list handling,
* or data type conversions are available as well. This is described in the chapter
* Basic features
* and AbstractConfiguration of the user's guide. There is also a separate chapter dealing with
* Properties files in
* special.
*
* @see java.util.Properties#load
*/
public class PropertiesConfiguration extends BaseConfiguration implements FileBasedConfiguration, FileLocatorAware {
/**
*
* A default implementation of the {@code IOFactory} interface.
*
*
* This class implements the {@code createXXXX()} methods defined by the {@code IOFactory} interface in a way that the
* default objects (i.e. {@code PropertiesReader} and {@code PropertiesWriter} are returned. Customizing either the
* reader or the writer (or both) can be done by extending this class and overriding the corresponding
* {@code createXXXX()} method.
*
*
* @since 1.7
*/
public static class DefaultIOFactory implements IOFactory {
/**
* The singleton instance.
*/
static final DefaultIOFactory INSTANCE = new DefaultIOFactory();
@Override
public PropertiesReader createPropertiesReader(final Reader in) {
return new PropertiesReader(in);
}
@Override
public PropertiesWriter createPropertiesWriter(final Writer out, final ListDelimiterHandler handler) {
return new PropertiesWriter(out, handler);
}
}
/**
*
* Definition of an interface that allows customization of read and write operations.
*
*
* For reading and writing properties files the inner classes {@code PropertiesReader} and {@code PropertiesWriter} are
* used. This interface defines factory methods for creating both a {@code PropertiesReader} and a
* {@code PropertiesWriter}. An object implementing this interface can be passed to the {@code setIOFactory()} method of
* {@code PropertiesConfiguration}. Every time the configuration is read or written the {@code IOFactory} is asked to
* create the appropriate reader or writer object. This provides an opportunity to inject custom reader or writer
* implementations.
*
*
* @since 1.7
*/
public interface IOFactory {
/**
* Creates a {@code PropertiesReader} for reading a properties file. This method is called whenever the
* {@code PropertiesConfiguration} is loaded. The reader returned by this method is then used for parsing the properties
* file.
*
* @param in the underlying reader (of the properties file)
* @return the {@code PropertiesReader} for loading the configuration
*/
PropertiesReader createPropertiesReader(Reader in);
/**
* Creates a {@code PropertiesWriter} for writing a properties file. This method is called before the
* {@code PropertiesConfiguration} is saved. The writer returned by this method is then used for writing the properties
* file.
*
* @param out the underlying writer (to the properties file)
* @param handler the list delimiter delimiter for list parsing
* @return the {@code PropertiesWriter} for saving the configuration
*/
PropertiesWriter createPropertiesWriter(Writer out, ListDelimiterHandler handler);
}
/**
* An alternative {@link IOFactory} that tries to mimic the behavior of {@link java.util.Properties} (Jup) more closely.
* The goal is to allow both of them be used interchangeably when reading and writing properties files without losing or
* changing information.
*
* It also has the option to not use Unicode escapes. When using UTF-8 encoding (which is e.g. the new default
* for resource bundle properties files since Java 9), Unicode escapes are no longer required and avoiding them makes
* properties files more readable with regular text editors.
*
* Some of the ways this implementation differs from {@link DefaultIOFactory}:
*
* - Trailing whitespace will not be trimmed from each line.
* - Unknown escape sequences will have their backslash removed.
* - {@code \b} is not a recognized escape sequence.
* - Leading spaces in property values are preserved by escaping them.
* - All natural lines (i.e. in the file) of a logical property line will have their leading whitespace trimmed.
* - Natural lines that look like comment lines within a logical line are not treated as such; they're part of the
* property value.
*
*
* @since 2.4
*/
public static class JupIOFactory implements IOFactory {
/**
* Whether characters less than {@code \u0020} and characters greater than {@code \u007E} in property keys or values
* should be escaped using Unicode escape sequences. Not necessary when e.g. writing as UTF-8.
*/
private final boolean escapeUnicode;
/**
* Constructs a new {@link JupIOFactory} with Unicode escaping.
*/
public JupIOFactory() {
this(true);
}
/**
* Constructs a new {@link JupIOFactory} with optional Unicode escaping. Whether Unicode escaping is required depends on
* the encoding used to save the properties file. E.g. for ISO-8859-1 this must be turned on, for UTF-8 it's not
* necessary. Unfortunately this factory can't determine the encoding on its own.
*
* @param escapeUnicode whether Unicode characters should be escaped
*/
public JupIOFactory(final boolean escapeUnicode) {
this.escapeUnicode = escapeUnicode;
}
@Override
public PropertiesReader createPropertiesReader(final Reader in) {
return new JupPropertiesReader(in);
}
@Override
public PropertiesWriter createPropertiesWriter(final Writer out, final ListDelimiterHandler handler) {
return new JupPropertiesWriter(out, handler, escapeUnicode);
}
}
/**
* A {@link PropertiesReader} that tries to mimic the behavior of {@link java.util.Properties}.
*
* @since 2.4
*/
public static class JupPropertiesReader extends PropertiesReader {
/**
* Constructs a new instance.
*
* @param reader A Reader.
*/
public JupPropertiesReader(final Reader reader) {
super(reader);
}
@Override
protected void parseProperty(final String line) {
final String[] property = doParseProperty(line, false);
initPropertyName(property[0]);
initPropertyValue(property[1]);
initPropertySeparator(property[2]);
}
@Override
public String readProperty() throws IOException {
getCommentLines().clear();
final StringBuilder buffer = new StringBuilder();
while (true) {
String line = readLine();
if (line == null) {
// EOF
if (buffer.length() > 0) {
break;
}
return null;
}
// while a property line continues there are no comments (even if the line from
// the file looks like one)
if (isCommentLine(line) && buffer.length() == 0) {
getCommentLines().add(line);
continue;
}
// while property line continues left trim all following lines read from the
// file
if (buffer.length() > 0) {
// index of the first non-whitespace character
int i;
for (i = 0; i < line.length(); i++) {
if (!Character.isWhitespace(line.charAt(i))) {
break;
}
}
line = line.substring(i);
}
if (!checkCombineLines(line)) {
buffer.append(line);
break;
}
line = line.substring(0, line.length() - 1);
buffer.append(line);
}
return buffer.toString();
}
@Override
protected String unescapePropertyValue(final String value) {
return unescapeJava(value, true);
}
}
/**
* A {@link PropertiesWriter} that tries to mimic the behavior of {@link java.util.Properties}.
*
* @since 2.4
*/
public static class JupPropertiesWriter extends PropertiesWriter {
/**
* The starting ASCII printable character.
*/
private static final int PRINTABLE_INDEX_END = 0x7e;
/**
* The ending ASCII printable character.
*/
private static final int PRINTABLE_INDEX_START = 0x20;
/**
* A UnicodeEscaper for characters outside the ASCII printable range.
*/
private static final UnicodeEscaper ESCAPER = UnicodeEscaper.outsideOf(PRINTABLE_INDEX_START, PRINTABLE_INDEX_END);
/**
* Characters that need to be escaped when wring a properties file.
*/
private static final Map JUP_CHARS_ESCAPE;
static {
final Map initialMap = new HashMap<>();
initialMap.put("\\", "\\\\");
initialMap.put("\n", "\\n");
initialMap.put("\t", "\\t");
initialMap.put("\f", "\\f");
initialMap.put("\r", "\\r");
JUP_CHARS_ESCAPE = Collections.unmodifiableMap(initialMap);
}
/**
* Creates a new instance of {@code JupPropertiesWriter}.
*
* @param writer a Writer object providing the underlying stream
* @param delHandler the delimiter handler for dealing with properties with multiple values
* @param escapeUnicode whether Unicode characters should be escaped using Unicode escapes
*/
public JupPropertiesWriter(final Writer writer, final ListDelimiterHandler delHandler, final boolean escapeUnicode) {
super(writer, delHandler, value -> {
String valueString = String.valueOf(value);
final CharSequenceTranslator translator;
if (escapeUnicode) {
translator = new AggregateTranslator(new LookupTranslator(JUP_CHARS_ESCAPE), ESCAPER);
} else {
translator = new AggregateTranslator(new LookupTranslator(JUP_CHARS_ESCAPE));
}
valueString = translator.translate(valueString);
// escape the first leading space to preserve it (and all after it)
if (valueString.startsWith(" ")) {
valueString = "\\" + valueString;
}
return valueString;
});
}
}
/**
* This class is used to read properties lines. These lines do not terminate with new-line chars but rather when there
* is no backslash sign a the end of the line. This is used to concatenate multiple lines for readability.
*/
public static class PropertiesReader extends LineNumberReader {
/** The regular expression to parse the key and the value of a property. */
private static final Pattern PROPERTY_PATTERN = Pattern
.compile("(([\\S&&[^\\\\" + new String(SEPARATORS) + "]]|\\\\.)*+)(\\s*(\\s+|[" + new String(SEPARATORS) + "])\\s*)?(.*)");
/** Constant for the index of the group for the key. */
private static final int IDX_KEY = 1;
/** Constant for the index of the group for the value. */
private static final int IDX_VALUE = 5;
/** Constant for the index of the group for the separator. */
private static final int IDX_SEPARATOR = 3;
/**
* Checks if the passed in line should be combined with the following. This is true, if the line ends with an odd number
* of backslashes.
*
* @param line the line
* @return a flag if the lines should be combined
*/
static boolean checkCombineLines(final String line) {
return countTrailingBS(line) % 2 != 0;
}
/**
* Parse a property line and return the key, the value, and the separator in an array.
*
* @param line the line to parse
* @param trimValue flag whether the value is to be trimmed
* @return an array with the property's key, value, and separator
*/
static String[] doParseProperty(final String line, final boolean trimValue) {
final Matcher matcher = PROPERTY_PATTERN.matcher(line);
final String[] result = {"", "", ""};
if (matcher.matches()) {
result[0] = matcher.group(IDX_KEY).trim();
String value = matcher.group(IDX_VALUE);
if (trimValue) {
value = value.trim();
}
result[1] = value;
result[2] = matcher.group(IDX_SEPARATOR);
}
return result;
}
/** Stores the comment lines for the currently processed property. */
private final List commentLines;
/** Stores the name of the last read property. */
private String propertyName;
/** Stores the value of the last read property. */
private String propertyValue;
/** Stores the property separator of the last read property. */
private String propertySeparator = DEFAULT_SEPARATOR;
/**
* Constructs a new instance.
*
* @param reader A Reader.
*/
public PropertiesReader(final Reader reader) {
super(reader);
commentLines = new ArrayList<>();
}
/**
* Gets the comment lines that have been read for the last property.
*
* @return the comment lines for the last property returned by {@code readProperty()}
* @since 1.3
*/
public List getCommentLines() {
return commentLines;
}
/**
* Gets the name of the last read property. This method can be called after {@link #nextProperty()} was invoked and
* its return value was true.
*
* @return the name of the last read property
* @since 1.3
*/
public String getPropertyName() {
return propertyName;
}
/**
* Gets the separator that was used for the last read property. The separator can be stored so that it can later be
* restored when saving the configuration.
*
* @return the separator for the last read property
* @since 1.7
*/
public String getPropertySeparator() {
return propertySeparator;
}
/**
* Gets the value of the last read property. This method can be called after {@link #nextProperty()} was invoked and
* its return value was true.
*
* @return the value of the last read property
* @since 1.3
*/
public String getPropertyValue() {
return propertyValue;
}
/**
* Sets the name of the current property. This method can be called by {@code parseProperty()} for storing the results
* of the parse operation. It also ensures that the property key is correctly escaped.
*
* @param name the name of the current property
* @since 1.7
*/
protected void initPropertyName(final String name) {
propertyName = unescapePropertyName(name);
}
/**
* Sets the separator of the current property. This method can be called by {@code parseProperty()}. It allows the
* associated layout object to keep track of the property separators. When saving the configuration the separators can
* be restored.
*
* @param value the separator used for the current property
* @since 1.7
*/
protected void initPropertySeparator(final String value) {
propertySeparator = value;
}
/**
* Sets the value of the current property. This method can be called by {@code parseProperty()} for storing the results
* of the parse operation. It also ensures that the property value is correctly escaped.
*
* @param value the value of the current property
* @since 1.7
*/
protected void initPropertyValue(final String value) {
propertyValue = unescapePropertyValue(value);
}
/**
* Parses the next property from the input stream and stores the found name and value in internal fields. These fields
* can be obtained using the provided getter methods. The return value indicates whether EOF was reached (false)
* or whether further properties are available (true).
*
* @return a flag if further properties are available
* @throws IOException if an error occurs
* @since 1.3
*/
public boolean nextProperty() throws IOException {
final String line = readProperty();
if (line == null) {
return false; // EOF
}
// parse the line
parseProperty(line);
return true;
}
/**
* Parses a line read from the properties file. This method is called for each non-comment line read from the source
* file. Its task is to split the passed in line into the property key and its value. The results of the parse operation
* can be stored by calling the {@code initPropertyXXX()} methods.
*
* @param line the line read from the properties file
* @since 1.7
*/
protected void parseProperty(final String line) {
final String[] property = doParseProperty(line, true);
initPropertyName(property[0]);
initPropertyValue(property[1]);
initPropertySeparator(property[2]);
}
/**
* Reads a property line. Returns null if Stream is at EOF. Concatenates lines ending with "\". Skips lines beginning
* with "#" or "!" and empty lines. The return value is a property definition ({@code <name>} =
* {@code <value>})
*
* @return A string containing a property value or null
*
* @throws IOException in case of an I/O error
*/
public String readProperty() throws IOException {
commentLines.clear();
final StringBuilder buffer = new StringBuilder();
while (true) {
String line = readLine();
if (line == null) {
// EOF
return null;
}
if (isCommentLine(line)) {
commentLines.add(line);
continue;
}
line = line.trim();
if (!checkCombineLines(line)) {
buffer.append(line);
break;
}
line = line.substring(0, line.length() - 1);
buffer.append(line);
}
return buffer.toString();
}
/**
* Performs unescaping on the given property name.
*
* @param name the property name
* @return the unescaped property name
* @since 2.4
*/
protected String unescapePropertyName(final String name) {
return StringEscapeUtils.unescapeJava(name);
}
/**
* Performs unescaping on the given property value.
*
* @param value the property value
* @return the unescaped property value
* @since 2.4
*/
protected String unescapePropertyValue(final String value) {
return unescapeJava(value);
}
} // class PropertiesReader
/**
* This class is used to write properties lines. The most important method is
* {@code writeProperty(String, Object, boolean)}, which is called during a save operation for each property found in
* the configuration.
*/
public static class PropertiesWriter extends FilterWriter {
/**
* Properties escape map.
*/
private static final Map PROPERTIES_CHARS_ESCAPE;
static {
final Map initialMap = new HashMap<>();
initialMap.put("\\", "\\\\");
PROPERTIES_CHARS_ESCAPE = Collections.unmodifiableMap(initialMap);
}
/**
* A translator for escaping property values. This translator performs a subset of transformations done by the
* ESCAPE_JAVA translator from Commons Lang 3.
*/
private static final CharSequenceTranslator ESCAPE_PROPERTIES = new AggregateTranslator(new LookupTranslator(PROPERTIES_CHARS_ESCAPE),
new LookupTranslator(EntityArrays.JAVA_CTRL_CHARS_ESCAPE), UnicodeEscaper.outsideOf(32, 0x7f));
/**
* A {@code ValueTransformer} implementation used to escape property values. This implementation applies the
* transformation defined by the {@link #ESCAPE_PROPERTIES} translator.
*/
private static final ValueTransformer DEFAULT_TRANSFORMER = value -> {
final String strVal = String.valueOf(value);
return ESCAPE_PROPERTIES.translate(strVal);
};
/** The value transformer used for escaping property values. */
private final ValueTransformer valueTransformer;
/** The list delimiter handler. */
private final ListDelimiterHandler delimiterHandler;
/** The separator to be used for the current property. */
private String currentSeparator;
/** The global separator. If set, it overrides the current separator. */
private String globalSeparator;
/** The line separator. */
private String lineSeparator;
/**
* Creates a new instance of {@code PropertiesWriter}.
*
* @param writer a Writer object providing the underlying stream
* @param delHandler the delimiter handler for dealing with properties with multiple values
*/
public PropertiesWriter(final Writer writer, final ListDelimiterHandler delHandler) {
this(writer, delHandler, DEFAULT_TRANSFORMER);
}
/**
* Creates a new instance of {@code PropertiesWriter}.
*
* @param writer a Writer object providing the underlying stream
* @param delHandler the delimiter handler for dealing with properties with multiple values
* @param valueTransformer the value transformer used to escape property values
*/
public PropertiesWriter(final Writer writer, final ListDelimiterHandler delHandler, final ValueTransformer valueTransformer) {
super(writer);
delimiterHandler = delHandler;
this.valueTransformer = valueTransformer;
}
/**
* Escapes the key of a property before it gets written to file. This method is called on saving a configuration for
* each property key. It ensures that separator characters contained in the key are escaped.
*
* @param key the key
* @return the escaped key
* @since 2.0
*/
protected String escapeKey(final String key) {
final StringBuilder newkey = new StringBuilder();
for (int i = 0; i < key.length(); i++) {
final char c = key.charAt(i);
if (ArrayUtils.contains(SEPARATORS, c) || ArrayUtils.contains(WHITE_SPACE, c) || c == '\\') {
// escape the separator
newkey.append('\\');
}
newkey.append(c);
}
return newkey.toString();
}
/**
* Returns the separator to be used for the given property. This method is called by {@code writeProperty()}. The string
* returned here is used as separator between the property key and its value. Per default the method checks whether a
* global separator is set. If this is the case, it is returned. Otherwise the separator returned by
* {@code getCurrentSeparator()} is used, which was set by the associated layout object. Derived classes may implement a
* different strategy for defining the separator.
*
* @param key the property key
* @param value the value
* @return the separator to be used
* @since 1.7
*/
protected String fetchSeparator(final String key, final Object value) {
return getGlobalSeparator() != null ? getGlobalSeparator() : StringUtils.defaultString(getCurrentSeparator());
}
/**
* Gets the current property separator.
*
* @return the current property separator
* @since 1.7
*/
public String getCurrentSeparator() {
return currentSeparator;
}
/**
* Gets the delimiter handler for properties with multiple values. This object is used to escape property values so
* that they can be read in correctly the next time they are loaded.
*
* @return the delimiter handler for properties with multiple values
* @since 2.0
*/
public ListDelimiterHandler getDelimiterHandler() {
return delimiterHandler;
}
/**
* Gets the global property separator.
*
* @return the global property separator
* @since 1.7
*/
public String getGlobalSeparator() {
return globalSeparator;
}
/**
* Gets the line separator.
*
* @return the line separator
* @since 1.7
*/
public String getLineSeparator() {
return lineSeparator != null ? lineSeparator : LINE_SEPARATOR;
}
/**
* Sets the current property separator. This separator is used when writing the next property.
*
* @param currentSeparator the current property separator
* @since 1.7
*/
public void setCurrentSeparator(final String currentSeparator) {
this.currentSeparator = currentSeparator;
}
/**
* Sets the global property separator. This separator corresponds to the {@code globalSeparator} property of
* {@link PropertiesConfigurationLayout}. It defines the separator to be used for all properties. If it is undefined,
* the current separator is used.
*
* @param globalSeparator the global property separator
* @since 1.7
*/
public void setGlobalSeparator(final String globalSeparator) {
this.globalSeparator = globalSeparator;
}
/**
* Sets the line separator. Each line written by this writer is terminated with this separator. If not set, the
* platform-specific line separator is used.
*
* @param lineSeparator the line separator to be used
* @since 1.7
*/
public void setLineSeparator(final String lineSeparator) {
this.lineSeparator = lineSeparator;
}
/**
* Write a comment.
*
* @param comment the comment to write
* @throws IOException if an I/O error occurs.
*/
public void writeComment(final String comment) throws IOException {
writeln("# " + comment);
}
/**
* Helper method for writing a line with the platform specific line ending.
*
* @param s the content of the line (may be null)
* @throws IOException if an error occurs
* @since 1.3
*/
public void writeln(final String s) throws IOException {
if (s != null) {
write(s);
}
write(getLineSeparator());
}
/**
* Write a property.
*
* @param key The key of the property
* @param values The array of values of the property
*
* @throws IOException if an I/O error occurs.
*/
public void writeProperty(final String key, final List values) throws IOException {
for (final Object value : values) {
writeProperty(key, value);
}
}
/**
* Write a property.
*
* @param key the key of the property
* @param value the value of the property
*
* @throws IOException if an I/O error occurs.
*/
public void writeProperty(final String key, final Object value) throws IOException {
writeProperty(key, value, false);
}
/**
* Writes the given property and its value. If the value happens to be a list, the {@code forceSingleLine} flag is
* evaluated. If it is set, all values are written on a single line using the list delimiter as separator.
*
* @param key the property key
* @param value the property value
* @param forceSingleLine the "force single line" flag
* @throws IOException if an error occurs
* @since 1.3
*/
public void writeProperty(final String key, final Object value, final boolean forceSingleLine) throws IOException {
String v;
if (value instanceof List) {
v = null;
final List values = (List) value;
if (forceSingleLine) {
try {
v = String.valueOf(getDelimiterHandler().escapeList(values, valueTransformer));
} catch (final UnsupportedOperationException ignored) {
// the handler may not support escaping lists,
// then the list is written in multiple lines
}
}
if (v == null) {
writeProperty(key, values);
return;
}
} else {
v = String.valueOf(getDelimiterHandler().escape(value, valueTransformer));
}
write(escapeKey(key));
write(fetchSeparator(key, value));
write(v);
writeln(null);
}
} // class PropertiesWriter
/**
* Defines default error handling for the special {@code "include"} key by throwing the given exception.
*
* @since 2.6
*/
public static final ConfigurationConsumer DEFAULT_INCLUDE_LISTENER = e -> {
throw e;
};
/**
* Defines error handling as a noop for the special {@code "include"} key.
*
* @since 2.6
*/
public static final ConfigurationConsumer NOOP_INCLUDE_LISTENER = e -> { /* noop */ };
/**
* The default encoding (ISO-8859-1 as specified by https://docs.oracle.com/javase/8/docs/api/java/util/Properties.html)
*/
public static final String DEFAULT_ENCODING = StandardCharsets.ISO_8859_1.name();
/** Constant for the supported comment characters. */
static final String COMMENT_CHARS = "#!";
/** Constant for the default properties separator. */
static final String DEFAULT_SEPARATOR = " = ";
/**
* A string with special characters that need to be unescaped when reading a properties file.
* {@link java.util.Properties} escapes these characters when writing out a properties file.
*/
private static final String UNESCAPE_CHARACTERS = ":#=!\\\'\"";
/**
* This is the name of the property that can point to other properties file for including other properties files.
*/
private static String include = "include";
/**
* This is the name of the property that can point to other properties file for including other properties files.
*
* If the file is absent, processing continues normally.
*
*/
private static String includeOptional = "includeoptional";
/** The list of possible key/value separators */
private static final char[] SEPARATORS = {'=', ':'};
/** The white space characters used as key/value separators. */
private static final char[] WHITE_SPACE = {' ', '\t', '\f'};
/** Constant for the platform specific line separator. */
private static final String LINE_SEPARATOR = System.lineSeparator();
/** Constant for the radix of hex numbers. */
private static final int HEX_RADIX = 16;
/** Constant for the length of a unicode literal. */
private static final int UNICODE_LEN = 4;
/**
* Returns the number of trailing backslashes. This is sometimes needed for the correct handling of escape characters.
*
* @param line the string to investigate
* @return the number of trailing backslashes
*/
private static int countTrailingBS(final String line) {
int bsCount = 0;
for (int idx = line.length() - 1; idx >= 0 && line.charAt(idx) == '\\'; idx--) {
bsCount++;
}
return bsCount;
}
/**
* Gets the property value for including other properties files. By default it is "include".
*
* @return A String.
*/
public static String getInclude() {
return include;
}
/**
* Gets the property value for including other properties files. By default it is "includeoptional".
*
* If the file is absent, processing continues normally.
*
*
* @return A String.
* @since 2.5
*/
public static String getIncludeOptional() {
return includeOptional;
}
/**
* Tests whether a line is a comment, i.e. whether it starts with a comment character.
*
* @param line the line
* @return a flag if this is a comment line
* @since 1.3
*/
static boolean isCommentLine(final String line) {
final String s = line.trim();
// blank lines are also treated as comment lines
return s.isEmpty() || COMMENT_CHARS.indexOf(s.charAt(0)) >= 0;
}
/**
* Checks whether the specified character needs to be unescaped. This method is called when during reading a property
* file an escape character ('\') is detected. If the character following the escape character is recognized as a
* special character which is escaped per default in a Java properties file, it has to be unescaped.
*
* @param ch the character in question
* @return a flag whether this character has to be unescaped
*/
private static boolean needsUnescape(final char ch) {
return UNESCAPE_CHARACTERS.indexOf(ch) >= 0;
}
/**
* Sets the property value for including other properties files. By default it is "include".
*
* @param inc A String.
*/
public static void setInclude(final String inc) {
include = inc;
}
/**
* Sets the property value for including other properties files. By default it is "include".
*
* If the file is absent, processing continues normally.
*
*
* @param inc A String.
* @since 2.5
*/
public static void setIncludeOptional(final String inc) {
includeOptional = inc;
}
/**
*
* Unescapes any Java literals found in the {@code String} to a {@code Writer}.
*
* This is a slightly modified version of the StringEscapeUtils.unescapeJava() function in commons-lang that doesn't
* drop escaped separators (i.e '\,').
*
* @param str the {@code String} to unescape, may be null
* @return the processed string
* @throws IllegalArgumentException if the Writer is {@code null}
*/
protected static String unescapeJava(final String str) {
return unescapeJava(str, false);
}
/**
* Unescapes Java literals found in the {@code String} to a {@code Writer}.
*
* When the parameter {@code jupCompatible} is {@code false}, the classic behavior is used (see
* {@link #unescapeJava(String)}). When it's {@code true} a slightly different behavior that's compatible with
* {@link java.util.Properties} is used (see {@link JupIOFactory}).
*
*
* @param str the {@code String} to unescape, may be null
* @param jupCompatible whether unescaping is compatible with {@link java.util.Properties}; otherwise the classic
* behavior is used
* @return the processed string
* @throws IllegalArgumentException if the Writer is {@code null}
*/
protected static String unescapeJava(final String str, final boolean jupCompatible) {
if (str == null) {
return null;
}
final int sz = str.length();
final StringBuilder out = new StringBuilder(sz);
final StringBuilder unicode = new StringBuilder(UNICODE_LEN);
boolean hadSlash = false;
boolean inUnicode = false;
for (int i = 0; i < sz; i++) {
final char ch = str.charAt(i);
if (inUnicode) {
// if in unicode, then we're reading unicode
// values in somehow
unicode.append(ch);
if (unicode.length() == UNICODE_LEN) {
// unicode now contains the four hex digits
// which represents our unicode character
try {
final int value = Integer.parseInt(unicode.toString(), HEX_RADIX);
out.append((char) value);
unicode.setLength(0);
inUnicode = false;
hadSlash = false;
} catch (final NumberFormatException nfe) {
throw new ConfigurationRuntimeException("Unable to parse unicode value: " + unicode, nfe);
}
}
continue;
}
if (hadSlash) {
// handle an escaped value
hadSlash = false;
switch (ch) {
case 'r':
out.append('\r');
break;
case 'f':
out.append('\f');
break;
case 't':
out.append('\t');
break;
case 'n':
out.append('\n');
break;
default:
if (!jupCompatible && ch == 'b') {
out.append('\b');
} else if (ch == 'u') {
// uh-oh, we're in unicode country....
inUnicode = true;
} else {
// JUP simply throws away the \ of unknown escape sequences
if (!needsUnescape(ch) && !jupCompatible) {
out.append('\\');
}
out.append(ch);
}
break;
}
continue;
}
if (ch == '\\') {
hadSlash = true;
continue;
}
out.append(ch);
}
if (hadSlash) {
// then we're in the weird case of a \ at the end of the
// string, let's output it anyway.
out.append('\\');
}
return out.toString();
}
/** Stores the layout object. */
private PropertiesConfigurationLayout layout;
/** The include listener for the special {@code "include"} key. */
private ConfigurationConsumer includeListener;
/** The IOFactory for creating readers and writers. */
private IOFactory ioFactory;
/** The current {@code FileLocator}. */
private FileLocator locator;
/** Allow file inclusion or not */
private boolean includesAllowed = true;
/**
* Creates an empty PropertyConfiguration object which can be used to synthesize a new Properties file by adding values
* and then saving().
*/
public PropertiesConfiguration() {
installLayout(createLayout());
}
/**
* Creates a copy of this object.
*
* @return the copy
*/
@Override
public Object clone() {
final PropertiesConfiguration copy = (PropertiesConfiguration) super.clone();
if (layout != null) {
copy.setLayout(new PropertiesConfigurationLayout(layout));
}
return copy;
}
/**
* Creates a standard layout object. This configuration is initialized with such a standard layout.
*
* @return the newly created layout object
*/
private PropertiesConfigurationLayout createLayout() {
return new PropertiesConfigurationLayout();
}
/**
* Gets the footer comment. This is a comment at the very end of the file.
*
* @return the footer comment
* @since 2.0
*/
public String getFooter() {
beginRead(false);
try {
return getLayout().getFooterComment();
} finally {
endRead();
}
}
/**
* Gets the comment header.
*
* @return the comment header
* @since 1.1
*/
public String getHeader() {
beginRead(false);
try {
return getLayout().getHeaderComment();
} finally {
endRead();
}
}
/**
* Gets the current include listener, never null.
*
* @return the current include listener, never null.
* @since 2.6
*/
public ConfigurationConsumer getIncludeListener() {
return includeListener != null ? includeListener : DEFAULT_INCLUDE_LISTENER;
}
/**
* Gets the {@code IOFactory} to be used for creating readers and writers when loading or saving this configuration.
*
* @return the {@code IOFactory}
* @since 1.7
*/
public IOFactory getIOFactory() {
return ioFactory != null ? ioFactory : DefaultIOFactory.INSTANCE;
}
/**
* Gets the associated layout object.
*
* @return the associated layout object
* @since 1.3
*/
public PropertiesConfigurationLayout getLayout() {
return layout;
}
/**
* Stores the current {@code FileLocator} for a following IO operation. The {@code FileLocator} is needed to resolve
* include files with relative file names.
*
* @param locator the current {@code FileLocator}
* @since 2.0
*/
@Override
public void initFileLocator(final FileLocator locator) {
this.locator = locator;
}
/**
* Installs a layout object. It has to be ensured that the layout is registered as change listener at this
* configuration. If there is already a layout object installed, it has to be removed properly.
*
* @param layout the layout object to be installed
*/
private void installLayout(final PropertiesConfigurationLayout layout) {
// only one layout must exist
if (this.layout != null) {
removeEventListener(ConfigurationEvent.ANY, this.layout);
}
if (layout == null) {
this.layout = createLayout();
} else {
this.layout = layout;
}
addEventListener(ConfigurationEvent.ANY, this.layout);
}
/**
* Reports the status of file inclusion.
*
* @return True if include files are loaded.
*/
public boolean isIncludesAllowed() {
return this.includesAllowed;
}
/**
* Helper method for loading an included properties file. This method is called by {@code load()} when an
* {@code include} property is encountered. It tries to resolve relative file names based on the current base path. If
* this fails, a resolution based on the location of this properties file is tried.
*
* @param fileName the name of the file to load
* @param optional whether or not the {@code fileName} is optional
* @param seenStack Stack of seen include URLs
* @throws ConfigurationException if loading fails
*/
private void loadIncludeFile(final String fileName, final boolean optional, final Deque seenStack) throws ConfigurationException {
if (locator == null) {
throw new ConfigurationException(
"Load operation not properly " + "initialized! Do not call read(InputStream) directly," + " but use a FileHandler to load a configuration.");
}
URL url = locateIncludeFile(locator.getBasePath(), fileName);
if (url == null) {
final URL baseURL = locator.getSourceURL();
if (baseURL != null) {
url = locateIncludeFile(baseURL.toString(), fileName);
}
}
if (optional && url == null) {
return;
}
if (url == null) {
getIncludeListener().accept(new ConfigurationException("Cannot resolve include file " + fileName, new FileNotFoundException(fileName)));
} else {
final FileHandler fh = new FileHandler(this);
fh.setFileLocator(locator);
final FileLocator orgLocator = locator;
try {
try {
// Check for cycles
if (seenStack.contains(url)) {
throw new ConfigurationException(String.format("Cycle detected loading %s, seen stack: %s", url, seenStack));
}
seenStack.add(url);
try {
fh.load(url);
} finally {
seenStack.pop();
}
} catch (final ConfigurationException e) {
getIncludeListener().accept(e);
}
} finally {
locator = orgLocator; // reset locator which is changed by load
}
}
}
/**
* Tries to obtain the URL of an include file using the specified (optional) base path and file name.
*
* @param basePath the base path
* @param fileName the file name
* @return the URL of the include file or null if it cannot be resolved
*/
private URL locateIncludeFile(final String basePath, final String fileName) {
final FileLocator includeLocator = FileLocatorUtils.fileLocator(locator).sourceURL(null).basePath(basePath).fileName(fileName).create();
return FileLocatorUtils.locate(includeLocator);
}
/**
* This method is invoked by the associated {@link PropertiesConfigurationLayout} object for each property definition
* detected in the parsed properties file. Its task is to check whether this is a special property definition (e.g. the
* {@code include} property). If not, the property must be added to this configuration. The return value indicates
* whether the property should be treated as a normal property. If it is false, the layout object will ignore
* this property.
*
* @param key the property key
* @param value the property value
* @param seenStack the stack of seen include URLs
* @return a flag whether this is a normal property
* @throws ConfigurationException if an error occurs
* @since 1.3
*/
boolean propertyLoaded(final String key, final String value, final Deque seenStack) throws ConfigurationException {
final boolean result;
if (StringUtils.isNotEmpty(getInclude()) && key.equalsIgnoreCase(getInclude())) {
if (isIncludesAllowed()) {
final Collection files = getListDelimiterHandler().split(value, true);
for (final String f : files) {
loadIncludeFile(interpolate(f), false, seenStack);
}
}
result = false;
} else if (StringUtils.isNotEmpty(getIncludeOptional()) && key.equalsIgnoreCase(getIncludeOptional())) {
if (isIncludesAllowed()) {
final Collection files = getListDelimiterHandler().split(value, true);
for (final String f : files) {
loadIncludeFile(interpolate(f), true, seenStack);
}
}
result = false;
} else {
addPropertyInternal(key, value);
result = true;
}
return result;
}
/**
* {@inheritDoc} This implementation delegates to the associated layout object which does the actual loading. Note that
* this method does not do any synchronization. This lies in the responsibility of the caller. (Typically, the caller is
* a {@code FileHandler} object which takes care for proper synchronization.)
*
* @since 2.0
*/
@Override
public void read(final Reader in) throws ConfigurationException, IOException {
getLayout().load(this, in);
}
/**
* Sets the footer comment. If set, this comment is written after all properties at the end of the file.
*
* @param footer the footer comment
* @since 2.0
*/
public void setFooter(final String footer) {
beginWrite(false);
try {
getLayout().setFooterComment(footer);
} finally {
endWrite();
}
}
/**
* Sets the comment header.
*
* @param header the header to use
* @since 1.1
*/
public void setHeader(final String header) {
beginWrite(false);
try {
getLayout().setHeaderComment(header);
} finally {
endWrite();
}
}
/**
* Sets the current include listener, may not be null.
*
* @param includeListener the current include listener, may not be null.
* @throws IllegalArgumentException if the {@code includeListener} is null.
* @since 2.6
*/
public void setIncludeListener(final ConfigurationConsumer includeListener) {
if (includeListener == null) {
throw new IllegalArgumentException("includeListener must not be null.");
}
this.includeListener = includeListener;
}
/**
* Controls whether additional files can be loaded by the {@code include = } statement or not. This is true
* per default.
*
* @param includesAllowed True if Includes are allowed.
*/
public void setIncludesAllowed(final boolean includesAllowed) {
this.includesAllowed = includesAllowed;
}
/**
* Sets the {@code IOFactory} to be used for creating readers and writers when loading or saving this configuration.
* Using this method a client can customize the reader and writer classes used by the load and save operations. Note
* that this method must be called before invoking one of the {@code load()} and {@code save()} methods. Especially, if
* you want to use a custom {@code IOFactory} for changing the {@code PropertiesReader}, you cannot load the
* configuration data in the constructor.
*
* @param ioFactory the new {@code IOFactory} (must not be null)
* @throws IllegalArgumentException if the {@code IOFactory} is null
* @since 1.7
*/
public void setIOFactory(final IOFactory ioFactory) {
if (ioFactory == null) {
throw new IllegalArgumentException("IOFactory must not be null.");
}
this.ioFactory = ioFactory;
}
/**
* Sets the associated layout object.
*
* @param layout the new layout object; can be null, then a new layout object will be created
* @since 1.3
*/
public void setLayout(final PropertiesConfigurationLayout layout) {
installLayout(layout);
}
/**
* {@inheritDoc} This implementation delegates to the associated layout object which does the actual saving. Note that,
* analogous to {@link #read(Reader)}, this method does not do any synchronization.
*
* @since 2.0
*/
@Override
public void write(final Writer out) throws ConfigurationException, IOException {
getLayout().save(this, out);
}
}