001/*
002 * Sonar, open source software quality management tool.
003 * Copyright (C) 2008-2012 SonarSource
004 * mailto:contact AT sonarsource DOT com
005 *
006 * Sonar is free software; you can redistribute it and/or
007 * modify it under the terms of the GNU Lesser General Public
008 * License as published by the Free Software Foundation; either
009 * version 3 of the License, or (at your option) any later version.
010 *
011 * Sonar is distributed in the hope that it will be useful,
012 * but WITHOUT ANY WARRANTY; without even the implied warranty of
013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014 * Lesser General Public License for more details.
015 *
016 * You should have received a copy of the GNU Lesser General Public
017 * License along with Sonar; if not, write to the Free Software
018 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019 */
020package org.sonar.java.signature;
021
022import java.util.ArrayList;
023import java.util.List;
024
025public final class ParameterSignatureScanner {
026
027  private final String signature;
028  private int index = 0;
029
030  private static final char ARRAY = '[';
031
032  private ParameterSignatureScanner(String parametersSignature) {
033    this.signature = parametersSignature;
034  }
035
036  public static Parameter scan(String parameterSignature) {
037    ParameterSignatureScanner scanner = new ParameterSignatureScanner(parameterSignature);
038    if (scanner.hasNext()) {
039      return scanner.next();
040    } else {
041      return null;
042    }
043  }
044
045  public static List<Parameter> scanArguments(String argumentsSignature) {
046    List<Parameter> arguments = new ArrayList<Parameter>();
047
048    ParameterSignatureScanner scanner = new ParameterSignatureScanner(argumentsSignature);
049    while (scanner.hasNext()) {
050      arguments.add(scanner.next());
051    }
052
053    return arguments;
054  }
055
056  private boolean hasNext() {
057    if (signature.length() > index && (signature.charAt(index) == ARRAY || nextCharIsJvmJavaType())) {
058      return true;
059    }
060    return false;
061  }
062
063  private boolean nextCharIsJvmJavaType() {
064    try {
065      JvmJavaType.valueOf(signature.substring(index, index + 1));
066      return true;
067    } catch (IllegalArgumentException e) {
068      return false;
069    }
070  }
071
072  private Parameter next() {
073    boolean isArray = false;
074    String classCanonicalName = null;
075
076    while (signature.charAt(index) == ARRAY) {
077      isArray = true;
078      index++;
079    }
080
081    JvmJavaType jvmJavaType = JvmJavaType.valueOf(signature.substring(index, index + 1));
082    index = index + 1;
083
084    if (jvmJavaType == JvmJavaType.L || jvmJavaType == JvmJavaType.T) {
085      int semicolonIndex = searchEndOfParameterSignature(signature, index);
086      int inferiorCharIndex = signature.indexOf('<', index);
087      if (inferiorCharIndex != -1 && inferiorCharIndex < semicolonIndex) {
088        classCanonicalName = signature.substring(index, signature.indexOf('<', index));
089      } else {
090        classCanonicalName = signature.substring(index, semicolonIndex);
091      }
092      index = semicolonIndex + 1;
093      jvmJavaType = JvmJavaType.L;
094    }
095    return new Parameter(jvmJavaType, classCanonicalName, isArray);
096  }
097
098  private int searchEndOfParameterSignature(String signature, int index) {
099    int genericDefinitionStack = 0;
100    for (; index < signature.length(); index++) {
101      char character = signature.charAt(index);
102      if (character == ';' && genericDefinitionStack == 0) {
103        return index;
104      }
105      if (character == '<') {
106        genericDefinitionStack++;
107      } else if (character == '>') {
108        genericDefinitionStack--;
109      }
110    }
111    throw new IllegalStateException("Unable to extract parameter signature from '" + signature + "'");
112  }
113}