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/*
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 * file:
 *
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 INRIA, France Telecom
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package jdk.internal.org.objectweb.asm.util;

import java.util.EnumSet;
import jdk.internal.org.objectweb.asm.Opcodes;
import jdk.internal.org.objectweb.asm.signature.SignatureVisitor;

A SignatureVisitor that checks that its methods are properly used.
Author:Eric Bruneton
/** * A {@link SignatureVisitor} that checks that its methods are properly used. * * @author Eric Bruneton */
public class CheckSignatureAdapter extends SignatureVisitor {
Type to be used to check class signatures. See CheckSignatureAdapter(int, SignatureVisitor).
/** * Type to be used to check class signatures. See {@link #CheckSignatureAdapter(int, * SignatureVisitor)}. */
public static final int CLASS_SIGNATURE = 0;
Type to be used to check method signatures. See CheckSignatureAdapter(int, SignatureVisitor).
/** * Type to be used to check method signatures. See {@link #CheckSignatureAdapter(int, * SignatureVisitor)}. */
public static final int METHOD_SIGNATURE = 1;
Type to be used to check type signatures.See CheckSignatureAdapter(int, SignatureVisitor).
/** * Type to be used to check type signatures.See {@link #CheckSignatureAdapter(int, * SignatureVisitor)}. */
public static final int TYPE_SIGNATURE = 2;
The valid automaton states for a visitFormalTypeParameter method call.
/** The valid automaton states for a {@link #visitFormalTypeParameter} method call. */
private static final EnumSet<State> VISIT_FORMAL_TYPE_PARAMETER_STATES = EnumSet.of(State.EMPTY, State.FORMAL, State.BOUND);
The valid automaton states for a visitClassBound method call.
/** The valid automaton states for a {@link #visitClassBound} method call. */
private static final EnumSet<State> VISIT_CLASS_BOUND_STATES = EnumSet.of(State.FORMAL);
The valid automaton states for a visitInterfaceBound method call.
/** The valid automaton states for a {@link #visitInterfaceBound} method call. */
private static final EnumSet<State> VISIT_INTERFACE_BOUND_STATES = EnumSet.of(State.FORMAL, State.BOUND);
The valid automaton states for a visitSuperclass method call.
/** The valid automaton states for a {@link #visitSuperclass} method call. */
private static final EnumSet<State> VISIT_SUPER_CLASS_STATES = EnumSet.of(State.EMPTY, State.FORMAL, State.BOUND);
The valid automaton states for a visitInterface method call.
/** The valid automaton states for a {@link #visitInterface} method call. */
private static final EnumSet<State> VISIT_INTERFACE_STATES = EnumSet.of(State.SUPER);
The valid automaton states for a visitParameterType method call.
/** The valid automaton states for a {@link #visitParameterType} method call. */
private static final EnumSet<State> VISIT_PARAMETER_TYPE_STATES = EnumSet.of(State.EMPTY, State.FORMAL, State.BOUND, State.PARAM);
The valid automaton states for a visitReturnType method call.
/** The valid automaton states for a {@link #visitReturnType} method call. */
private static final EnumSet<State> VISIT_RETURN_TYPE_STATES = EnumSet.of(State.EMPTY, State.FORMAL, State.BOUND, State.PARAM);
The valid automaton states for a visitExceptionType method call.
/** The valid automaton states for a {@link #visitExceptionType} method call. */
private static final EnumSet<State> VISIT_EXCEPTION_TYPE_STATES = EnumSet.of(State.RETURN);
The possible states of the automaton used to check the order of method calls.
/** The possible states of the automaton used to check the order of method calls. */
private enum State { EMPTY, FORMAL, BOUND, SUPER, PARAM, RETURN, SIMPLE_TYPE, CLASS_TYPE, END; } private static final String INVALID = "Invalid ";
The type of the visited signature.
/** The type of the visited signature. */
private final int type;
The current state of the automaton used to check the order of method calls.
/** The current state of the automaton used to check the order of method calls. */
private State state;
Whether the visited signature can be 'V'.
/** Whether the visited signature can be 'V'. */
private boolean canBeVoid;
The visitor to which this adapter must delegate calls. May be null.
/** The visitor to which this adapter must delegate calls. May be {@literal null}. */
private final SignatureVisitor signatureVisitor;
Constructs a new CheckSignatureAdapter. Subclasses must not use this constructor. Instead, they must use the CheckSignatureAdapter(int, int, SignatureVisitor) version.
Params:
/** * Constructs a new {@link CheckSignatureAdapter}. <i>Subclasses must not use this * constructor</i>. Instead, they must use the {@link #CheckSignatureAdapter(int, int, * SignatureVisitor)} version. * * @param type the type of signature to be checked. See {@link #CLASS_SIGNATURE}, {@link * #METHOD_SIGNATURE} and {@link #TYPE_SIGNATURE}. * @param signatureVisitor the visitor to which this adapter must delegate calls. May be {@literal * null}. */
public CheckSignatureAdapter(final int type, final SignatureVisitor signatureVisitor) { this(/* latest api = */ Opcodes.ASM8, type, signatureVisitor); }
Constructs a new CheckSignatureAdapter.
Params:
/** * Constructs a new {@link CheckSignatureAdapter}. * * @param api the ASM API version implemented by this visitor. Must be one of {@link * Opcodes#ASM4}, {@link Opcodes#ASM5}, {@link Opcodes#ASM6}, {@link Opcodes#ASM7} or {@link * Opcodes#ASM8}. * @param type the type of signature to be checked. See {@link #CLASS_SIGNATURE}, {@link * #METHOD_SIGNATURE} and {@link #TYPE_SIGNATURE}. * @param signatureVisitor the visitor to which this adapter must delegate calls. May be {@literal * null}. */
protected CheckSignatureAdapter( final int api, final int type, final SignatureVisitor signatureVisitor) { super(api); this.type = type; this.state = State.EMPTY; this.signatureVisitor = signatureVisitor; } // class and method signatures @Override public void visitFormalTypeParameter(final String name) { if (type == TYPE_SIGNATURE || !VISIT_FORMAL_TYPE_PARAMETER_STATES.contains(state)) { throw new IllegalStateException(); } checkIdentifier(name, "formal type parameter"); state = State.FORMAL; if (signatureVisitor != null) { signatureVisitor.visitFormalTypeParameter(name); } } @Override public SignatureVisitor visitClassBound() { if (type == TYPE_SIGNATURE || !VISIT_CLASS_BOUND_STATES.contains(state)) { throw new IllegalStateException(); } state = State.BOUND; return new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitClassBound()); } @Override public SignatureVisitor visitInterfaceBound() { if (type == TYPE_SIGNATURE || !VISIT_INTERFACE_BOUND_STATES.contains(state)) { throw new IllegalStateException(); } return new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitInterfaceBound()); } // class signatures @Override public SignatureVisitor visitSuperclass() { if (type != CLASS_SIGNATURE || !VISIT_SUPER_CLASS_STATES.contains(state)) { throw new IllegalStateException(); } state = State.SUPER; return new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitSuperclass()); } @Override public SignatureVisitor visitInterface() { if (type != CLASS_SIGNATURE || !VISIT_INTERFACE_STATES.contains(state)) { throw new IllegalStateException(); } return new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitInterface()); } // method signatures @Override public SignatureVisitor visitParameterType() { if (type != METHOD_SIGNATURE || !VISIT_PARAMETER_TYPE_STATES.contains(state)) { throw new IllegalStateException(); } state = State.PARAM; return new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitParameterType()); } @Override public SignatureVisitor visitReturnType() { if (type != METHOD_SIGNATURE || !VISIT_RETURN_TYPE_STATES.contains(state)) { throw new IllegalStateException(); } state = State.RETURN; CheckSignatureAdapter checkSignatureAdapter = new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitReturnType()); checkSignatureAdapter.canBeVoid = true; return checkSignatureAdapter; } @Override public SignatureVisitor visitExceptionType() { if (type != METHOD_SIGNATURE || !VISIT_EXCEPTION_TYPE_STATES.contains(state)) { throw new IllegalStateException(); } return new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitExceptionType()); } // type signatures @Override public void visitBaseType(final char descriptor) { if (type != TYPE_SIGNATURE || state != State.EMPTY) { throw new IllegalStateException(); } if (descriptor == 'V') { if (!canBeVoid) { throw new IllegalArgumentException("Base type descriptor can't be V"); } } else { if ("ZCBSIFJD".indexOf(descriptor) == -1) { throw new IllegalArgumentException("Base type descriptor must be one of ZCBSIFJD"); } } state = State.SIMPLE_TYPE; if (signatureVisitor != null) { signatureVisitor.visitBaseType(descriptor); } } @Override public void visitTypeVariable(final String name) { if (type != TYPE_SIGNATURE || state != State.EMPTY) { throw new IllegalStateException(); } checkIdentifier(name, "type variable"); state = State.SIMPLE_TYPE; if (signatureVisitor != null) { signatureVisitor.visitTypeVariable(name); } } @Override public SignatureVisitor visitArrayType() { if (type != TYPE_SIGNATURE || state != State.EMPTY) { throw new IllegalStateException(); } state = State.SIMPLE_TYPE; return new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitArrayType()); } @Override public void visitClassType(final String name) { if (type != TYPE_SIGNATURE || state != State.EMPTY) { throw new IllegalStateException(); } checkClassName(name, "class name"); state = State.CLASS_TYPE; if (signatureVisitor != null) { signatureVisitor.visitClassType(name); } } @Override public void visitInnerClassType(final String name) { if (state != State.CLASS_TYPE) { throw new IllegalStateException(); } checkIdentifier(name, "inner class name"); if (signatureVisitor != null) { signatureVisitor.visitInnerClassType(name); } } @Override public void visitTypeArgument() { if (state != State.CLASS_TYPE) { throw new IllegalStateException(); } if (signatureVisitor != null) { signatureVisitor.visitTypeArgument(); } } @Override public SignatureVisitor visitTypeArgument(final char wildcard) { if (state != State.CLASS_TYPE) { throw new IllegalStateException(); } if ("+-=".indexOf(wildcard) == -1) { throw new IllegalArgumentException("Wildcard must be one of +-="); } return new CheckSignatureAdapter( TYPE_SIGNATURE, signatureVisitor == null ? null : signatureVisitor.visitTypeArgument(wildcard)); } @Override public void visitEnd() { if (state != State.CLASS_TYPE) { throw new IllegalStateException(); } state = State.END; if (signatureVisitor != null) { signatureVisitor.visitEnd(); } } private void checkClassName(final String name, final String message) { if (name == null || name.length() == 0) { throw new IllegalArgumentException(INVALID + message + " (must not be null or empty)"); } for (int i = 0; i < name.length(); ++i) { if (".;[<>:".indexOf(name.charAt(i)) != -1) { throw new IllegalArgumentException( INVALID + message + " (must not contain . ; [ < > or :): " + name); } } } private void checkIdentifier(final String name, final String message) { if (name == null || name.length() == 0) { throw new IllegalArgumentException(INVALID + message + " (must not be null or empty)"); } for (int i = 0; i < name.length(); ++i) { if (".;[/<>:".indexOf(name.charAt(i)) != -1) { throw new IllegalArgumentException( INVALID + message + " (must not contain . ; [ / < > or :): " + name); } } } }