/*
 * Copyright 2012-2019 the original author or authors.
 *
 * 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
 *
 *      https://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.springframework.boot.env;

import java.io.Closeable;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.LineNumberReader;
import java.nio.charset.StandardCharsets;
import java.util.LinkedHashMap;
import java.util.Map;

import org.springframework.boot.origin.Origin;
import org.springframework.boot.origin.OriginTrackedValue;
import org.springframework.boot.origin.TextResourceOrigin;
import org.springframework.boot.origin.TextResourceOrigin.Location;
import org.springframework.core.io.Resource;
import org.springframework.util.Assert;

Class to load .properties files into a map of String -> OriginTrackedValue. Also supports expansion of name[]=a,b,c list style values.
Author:Madhura Bhave, Phillip Webb, Thiago Hirata
/** * Class to load {@code .properties} files into a map of {@code String} -> * {@link OriginTrackedValue}. Also supports expansion of {@code name[]=a,b,c} list style * values. * * @author Madhura Bhave * @author Phillip Webb * @author Thiago Hirata */
class OriginTrackedPropertiesLoader { private final Resource resource;
Create a new OriginTrackedPropertiesLoader instance.
Params:
  • resource – the resource of the .properties data
/** * Create a new {@link OriginTrackedPropertiesLoader} instance. * @param resource the resource of the {@code .properties} data */
OriginTrackedPropertiesLoader(Resource resource) { Assert.notNull(resource, "Resource must not be null"); this.resource = resource; }
Load .properties data and return a map of String -> OriginTrackedValue.
Throws:
Returns:the loaded properties
/** * Load {@code .properties} data and return a map of {@code String} -> * {@link OriginTrackedValue}. * @return the loaded properties * @throws IOException on read error */
Map<String, OriginTrackedValue> load() throws IOException { return load(true); }
Load .properties data and return a map of String -> OriginTrackedValue.
Params:
  • expandLists – if list name[]=a,b,c shortcuts should be expanded
Throws:
Returns:the loaded properties
/** * Load {@code .properties} data and return a map of {@code String} -> * {@link OriginTrackedValue}. * @param expandLists if list {@code name[]=a,b,c} shortcuts should be expanded * @return the loaded properties * @throws IOException on read error */
Map<String, OriginTrackedValue> load(boolean expandLists) throws IOException { try (CharacterReader reader = new CharacterReader(this.resource)) { Map<String, OriginTrackedValue> result = new LinkedHashMap<>(); StringBuilder buffer = new StringBuilder(); while (reader.read()) { String key = loadKey(buffer, reader).trim(); if (expandLists && key.endsWith("[]")) { key = key.substring(0, key.length() - 2); int index = 0; do { OriginTrackedValue value = loadValue(buffer, reader, true); put(result, key + "[" + (index++) + "]", value); if (!reader.isEndOfLine()) { reader.read(); } } while (!reader.isEndOfLine()); } else { OriginTrackedValue value = loadValue(buffer, reader, false); put(result, key, value); } } return result; } } private void put(Map<String, OriginTrackedValue> result, String key, OriginTrackedValue value) { if (!key.isEmpty()) { result.put(key, value); } } private String loadKey(StringBuilder buffer, CharacterReader reader) throws IOException { buffer.setLength(0); boolean previousWhitespace = false; while (!reader.isEndOfLine()) { if (reader.isPropertyDelimiter()) { reader.read(); return buffer.toString(); } if (!reader.isWhiteSpace() && previousWhitespace) { return buffer.toString(); } previousWhitespace = reader.isWhiteSpace(); buffer.append(reader.getCharacter()); reader.read(); } return buffer.toString(); } private OriginTrackedValue loadValue(StringBuilder buffer, CharacterReader reader, boolean splitLists) throws IOException { buffer.setLength(0); while (reader.isWhiteSpace() && !reader.isEndOfLine()) { reader.read(); } Location location = reader.getLocation(); while (!reader.isEndOfLine() && !(splitLists && reader.isListDelimiter())) { buffer.append(reader.getCharacter()); reader.read(); } Origin origin = new TextResourceOrigin(this.resource, location); return OriginTrackedValue.of(buffer.toString(), origin); }
Reads characters from the source resource, taking care of skipping comments, handling multi-line values and tracking '\' escapes.
/** * Reads characters from the source resource, taking care of skipping comments, * handling multi-line values and tracking {@code '\'} escapes. */
private static class CharacterReader implements Closeable { private static final String[] ESCAPES = { "trnf", "\t\r\n\f" }; private final LineNumberReader reader; private int columnNumber = -1; private boolean escaped; private int character; CharacterReader(Resource resource) throws IOException { this.reader = new LineNumberReader( new InputStreamReader(resource.getInputStream(), StandardCharsets.ISO_8859_1)); } @Override public void close() throws IOException { this.reader.close(); } boolean read() throws IOException { return read(false); } boolean read(boolean wrappedLine) throws IOException { this.escaped = false; this.character = this.reader.read(); this.columnNumber++; if (this.columnNumber == 0) { skipLeadingWhitespace(); if (!wrappedLine) { skipComment(); } } if (this.character == '\\') { this.escaped = true; readEscaped(); } else if (this.character == '\n') { this.columnNumber = -1; } return !isEndOfFile(); } private void skipLeadingWhitespace() throws IOException { while (isWhiteSpace()) { this.character = this.reader.read(); this.columnNumber++; } } private void skipComment() throws IOException { if (this.character == '#' || this.character == '!') { while (this.character != '\n' && this.character != -1) { this.character = this.reader.read(); } this.columnNumber = -1; read(); } } private void readEscaped() throws IOException { this.character = this.reader.read(); int escapeIndex = ESCAPES[0].indexOf(this.character); if (escapeIndex != -1) { this.character = ESCAPES[1].charAt(escapeIndex); } else if (this.character == '\n') { this.columnNumber = -1; read(true); } else if (this.character == 'u') { readUnicode(); } } private void readUnicode() throws IOException { this.character = 0; for (int i = 0; i < 4; i++) { int digit = this.reader.read(); if (digit >= '0' && digit <= '9') { this.character = (this.character << 4) + digit - '0'; } else if (digit >= 'a' && digit <= 'f') { this.character = (this.character << 4) + digit - 'a' + 10; } else if (digit >= 'A' && digit <= 'F') { this.character = (this.character << 4) + digit - 'A' + 10; } else { throw new IllegalStateException("Malformed \\uxxxx encoding."); } } } boolean isWhiteSpace() { return !this.escaped && (this.character == ' ' || this.character == '\t' || this.character == '\f'); } boolean isEndOfFile() { return this.character == -1; } boolean isEndOfLine() { return this.character == -1 || (!this.escaped && this.character == '\n'); } boolean isListDelimiter() { return !this.escaped && this.character == ','; } boolean isPropertyDelimiter() { return !this.escaped && (this.character == '=' || this.character == ':'); } char getCharacter() { return (char) this.character; } Location getLocation() { return new Location(this.reader.getLineNumber(), this.columnNumber); } } }