diff options
Diffstat (limited to 'framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/property/ParseProperties.java')
| -rw-r--r-- | framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/property/ParseProperties.java | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/property/ParseProperties.java b/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/property/ParseProperties.java new file mode 100644 index 00000000..f03f966e --- /dev/null +++ b/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/property/ParseProperties.java @@ -0,0 +1,199 @@ +/* + * 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.tools.ant.property; + +import java.text.ParsePosition; +import java.util.Collection; + +import org.apache.tools.ant.Project; + +/** + * Parse properties using a collection of expanders. + * + * @since Ant 1.8.0 + */ +public class ParseProperties implements ParseNextProperty { + + private final Project project; + private final GetProperty getProperty; + private final Collection<PropertyExpander> expanders; + + /** + * Constructor with a getProperty. + * @param project the current Ant project. + * @param expanders a sequence of expanders + * @param getProperty property resolver. + */ + public ParseProperties(Project project, Collection<PropertyExpander> expanders, GetProperty getProperty) { + this.project = project; + this.expanders = expanders; + this.getProperty = getProperty; + } + + /** + * Get the project. + * @return the current Ant project. + */ + public Project getProject() { + return project; + } + + /** + * Decode properties from a String representation. + * + * <ul> + * + * <li>This implementation starts parsing the <code>value</code> + * parameter (unsurprisingly) at the beginning and asks each + * {@link PropertyExpander PropertyExpander} whether there is a + * property reference at that point. PropertyExpanders return + * the name of a property they may find and may advance the parse + * position.</li> + * + * <li>If the PropertyExpander returns <code>null</code> the + * method continues with the next PropertyExpander, otherwise it + * tries to look up the property's value using the configured + * {@link GetProperty GetProperty} instance.</li> + * + * <li>Once all PropertyExpanders have been consulted, the parse + * position is advanced by one character and the process repeated + * until <code>value</code> is exhausted.</li> + * + * </ul> + * + * <p>If the entire contents of <code>value</code> resolves to a + * single property, the looked up property value is returned. + * Otherwise a String is returned that concatenates the + * non-property parts of <code>value</code> and the expanded + * values of the properties that have been found.</p> + * + * @param value The string to be scanned for property references. + * May be <code>null</code>, in which case this + * method returns immediately with no effect. + * + * @return the original string with the properties replaced, or + * <code>null</code> if the original string is <code>null</code>. + */ + public Object parseProperties(String value) { + if (value == null || "".equals(value)) { + return value; + } + final int len = value.length(); + ParsePosition pos = new ParsePosition(0); + Object o = parseNextProperty(value, pos); + if (o != null && pos.getIndex() >= len) { + return o; + } + StringBuffer sb = new StringBuffer(len * 2); + if (o == null) { + sb.append(value.charAt(pos.getIndex())); + pos.setIndex(pos.getIndex() + 1); + } else { + sb.append(o); + } + while (pos.getIndex() < len) { + o = parseNextProperty(value, pos); + if (o == null) { + sb.append(value.charAt(pos.getIndex())); + pos.setIndex(pos.getIndex() + 1); + } else { + sb.append(o); + } + } + return sb.toString(); + } + + /** + * Learn whether a String contains replaceable properties. + * + * <p>Uses the configured {@link PropertyExpander + * PropertyExpanders} and scans through the string. Returns true + * as soon as any expander finds a property.</p> + * + * @param value the String to check. + * @return <code>true</code> if <code>value</code> contains property notation. + */ + public boolean containsProperties(String value) { + if (value == null) { + return false; + } + final int len = value.length(); + for (ParsePosition pos = new ParsePosition(0); pos.getIndex() < len;) { + if (parsePropertyName(value, pos) != null) { + return true; + } + pos.setIndex(pos.getIndex() + 1); + } + return false; + } + + /** + * Return any property that can be parsed from the specified position + * in the specified String. + * + * <p>Uses the configured {@link PropertyExpander + * PropertyExpanders} and {@link GetProperty GetProperty} + * instance .</p> + * + * @param value String to parse + * @param pos ParsePosition + * @return Object or null if no property is at the current + * location. If a property reference has been found but the + * property doesn't expand to a value, the property's name is + * returned. + */ + public Object parseNextProperty(String value, ParsePosition pos) { + final int start = pos.getIndex(); + + if (start > value.length()) { + // early exit, can't find any property here, no need to + // consult all the delegates. + return null; + } + + String propertyName = parsePropertyName(value, pos); + if (propertyName != null) { + Object result = getProperty(propertyName); + if (result != null) { + return result; + } + if (project != null) { + project.log( + "Property \"" + propertyName + + "\" has not been set", Project.MSG_VERBOSE); + } + return value.substring(start, pos.getIndex()); + } + return null; + } + + private String parsePropertyName(String value, ParsePosition pos) { + for (PropertyExpander propertyExpander : expanders) { + String propertyName = propertyExpander.parsePropertyName(value, pos, this); + if (propertyName == null) { + continue; + } + return propertyName; + } + return null; + } + + private Object getProperty(String propertyName) { + return getProperty.getProperty(propertyName); + } +} |