001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2016 the original author or authors.
004//
005// This library is free software; you can redistribute it and/or
006// modify it under the terms of the GNU Lesser General Public
007// License as published by the Free Software Foundation; either
008// version 2.1 of the License, or (at your option) any later version.
009//
010// This library is distributed in the hope that it will be useful,
011// but WITHOUT ANY WARRANTY; without even the implied warranty of
012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013// Lesser General Public License for more details.
014//
015// You should have received a copy of the GNU Lesser General Public
016// License along with this library; if not, write to the Free Software
017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
018////////////////////////////////////////////////////////////////////////////////
019
020package com.puppycrawl.tools.checkstyle.checks.metrics;
021
022import java.math.BigInteger;
023import java.util.ArrayDeque;
024import java.util.Deque;
025
026import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
027import com.puppycrawl.tools.checkstyle.api.DetailAST;
028import com.puppycrawl.tools.checkstyle.api.TokenTypes;
029
030/**
031 * Base class for checks the calculate complexity based around methods.
032 * @deprecated Checkstyle will not support abstract checks anymore. Use
033 *             {@link AbstractCheck} instead.
034 * @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a>
035 * @author Oliver Burn
036 * @noinspection AbstractClassNeverImplemented
037 */
038@Deprecated
039public abstract class AbstractComplexityCheck
040    extends AbstractCheck {
041    /** The initial current value. */
042    private static final BigInteger INITIAL_VALUE = BigInteger.ONE;
043
044    /** Stack of values - all but the current value. */
045    private final Deque<BigInteger> valueStack = new ArrayDeque<>();
046
047    /** The current value. */
048    private BigInteger currentValue = BigInteger.ZERO;
049
050    /** Threshold to report error for. */
051    private int max;
052
053    /**
054     * Creates an instance.
055     * @param max the threshold of when to report an error
056     */
057    protected AbstractComplexityCheck(int max) {
058        this.max = max;
059    }
060
061    /**
062     * Gets the message ID to log violations with.
063     * @return the message ID to log violations with
064     */
065    protected abstract String getMessageID();
066
067    /**
068     * Hook called when visiting a token. Will not be called the method
069     * definition tokens.
070     *
071     * @param ast the token being visited
072     */
073    protected abstract void visitTokenHook(DetailAST ast);
074
075    /**
076     * Hook called when leaving a token. Will not be called the method
077     * definition tokens.
078     *
079     * @param ast the token being left
080     */
081    protected abstract void leaveTokenHook(DetailAST ast);
082
083    @Override
084    public final int[] getRequiredTokens() {
085        return new int[] {
086            TokenTypes.CTOR_DEF,
087            TokenTypes.METHOD_DEF,
088            TokenTypes.INSTANCE_INIT,
089            TokenTypes.STATIC_INIT,
090        };
091    }
092
093    /**
094     * Set the maximum threshold allowed.
095     *
096     * @param max the maximum threshold
097     */
098    public final void setMax(int max) {
099        this.max = max;
100    }
101
102    @Override
103    public void visitToken(DetailAST ast) {
104        switch (ast.getType()) {
105            case TokenTypes.CTOR_DEF:
106            case TokenTypes.METHOD_DEF:
107            case TokenTypes.INSTANCE_INIT:
108            case TokenTypes.STATIC_INIT:
109                visitMethodDef();
110                break;
111            default:
112                visitTokenHook(ast);
113        }
114    }
115
116    @Override
117    public void leaveToken(DetailAST ast) {
118        switch (ast.getType()) {
119            case TokenTypes.CTOR_DEF:
120            case TokenTypes.METHOD_DEF:
121            case TokenTypes.INSTANCE_INIT:
122            case TokenTypes.STATIC_INIT:
123                leaveMethodDef(ast);
124                break;
125            default:
126                leaveTokenHook(ast);
127        }
128    }
129
130    /**
131     * Gets the current value.
132     * @return the current value
133     */
134    protected final BigInteger getCurrentValue() {
135        return currentValue;
136    }
137
138    /**
139     * Set the current value.
140     * @param value the new value
141     */
142    protected final void setCurrentValue(BigInteger value) {
143        currentValue = value;
144    }
145
146    /**
147     * Increments the current value by a specified amount.
148     *
149     * @param amount the amount to increment by
150     */
151    protected final void incrementCurrentValue(BigInteger amount) {
152        currentValue = currentValue.add(amount);
153    }
154
155    /** Push the current value on the stack. */
156    protected final void pushValue() {
157        valueStack.push(currentValue);
158        currentValue = INITIAL_VALUE;
159    }
160
161    /**
162     * Pops a value off the stack and makes it the current value.
163     * @return pop a value off the stack and make it the current value
164     */
165    protected final BigInteger popValue() {
166        currentValue = valueStack.pop();
167        return currentValue;
168    }
169
170    /** Process the start of the method definition. */
171    private void visitMethodDef() {
172        pushValue();
173    }
174
175    /**
176     * Process the end of a method definition.
177     *
178     * @param ast the token representing the method definition
179     */
180    private void leaveMethodDef(DetailAST ast) {
181        final BigInteger bigIntegerMax = BigInteger.valueOf(max);
182        if (currentValue.compareTo(bigIntegerMax) > 0) {
183            log(ast, getMessageID(), currentValue, bigIntegerMax);
184        }
185        popValue();
186    }
187}