Java example source code file (BinaryMember.java)

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Java - Java tags/keywords

binaryattribute, binaryconstantpool, binarymember, bytearrayinputstream, classdeclaration, compilererror, datainputstream, expression, identifier, ioexception, longexpression, m_synthetic, memberdefinition, util, vector

The BinaryMember.java Java example source code

/*
 * Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package sun.tools.java;

import sun.tools.tree.*;
import java.util.Vector;
import java.util.Hashtable;
import java.io.IOException;
import java.io.DataInputStream;
import java.io.ByteArrayInputStream;

/**
 * This class represents a binary member
 *
 * WARNING: The contents of this source file are not part of any
 * supported API.  Code that depends on them does so at its own risk:
 * they are subject to change or removal without notice.
 */
public final
class BinaryMember extends MemberDefinition {
    Expression value;
    BinaryAttribute atts;

    /**
     * Constructor
     */
    public BinaryMember(ClassDefinition clazz, int modifiers, Type type,
                       Identifier name, BinaryAttribute atts) {
        super(0, clazz, modifiers, type, name, null, null);
        this.atts = atts;

        // Was it compiled as deprecated?
        if (getAttribute(idDeprecated) != null) {
            this.modifiers |= M_DEPRECATED;
        }

        // Was it synthesized by the compiler?
        if (getAttribute(idSynthetic) != null) {
            this.modifiers |= M_SYNTHETIC;
        }
    }

    /**
     * Constructor for an inner class.
     */
    public BinaryMember(ClassDefinition innerClass) {
        super(innerClass);
    }

    /**
     * Inline allowed (currently only allowed for the constructor of Object).
     */
    public boolean isInlineable(Environment env, boolean fromFinal) {
        // It is possible for 'getSuperClass()' to return null due to error
        // recovery from cyclic inheritace.  Can this cause a problem here?
        return isConstructor() && (getClassDefinition().getSuperClass() == null);
    }

    /**
     * Get arguments
     */
    public Vector getArguments() {
        if (isConstructor() && (getClassDefinition().getSuperClass() == null)) {
            Vector v = new Vector();
            v.addElement(new LocalMember(0, getClassDefinition(), 0,
                                        getClassDefinition().getType(), idThis));
            return v;
        }
        return null;
    }

    /**
     * Get exceptions
     */
    public ClassDeclaration[] getExceptions(Environment env) {
        if ((!isMethod()) || (exp != null)) {
            return exp;
        }
        byte data[] = getAttribute(idExceptions);
        if (data == null) {
            return new ClassDeclaration[0];
        }

        try {
            BinaryConstantPool cpool = ((BinaryClass)getClassDefinition()).getConstants();
            DataInputStream in = new DataInputStream(new ByteArrayInputStream(data));
            // JVM 4.7.5 Exceptions_attribute.number_of_exceptions
            int n = in.readUnsignedShort();
            exp = new ClassDeclaration[n];
            for (int i = 0 ; i < n ; i++) {
                // JVM 4.7.5 Exceptions_attribute.exception_index_table[]
                exp[i] = cpool.getDeclaration(env, in.readUnsignedShort());
            }
            return exp;
        } catch (IOException e) {
            throw new CompilerError(e);
        }
    }

    /**
     * Get documentation
     */
    public String getDocumentation() {
        if (documentation != null) {
            return documentation;
        }
        byte data[] = getAttribute(idDocumentation);
        if (data == null) {
            return null;
        }
        try {
            return documentation = new DataInputStream(new ByteArrayInputStream(data)).readUTF();
        } catch (IOException e) {
            throw new CompilerError(e);
        }
    }

    /**
     * Check if constant:  Will it inline away to a constant?
     * This override is needed to solve bug 4128266.  It is also
     * integral to the solution of 4119776.
     */
    private boolean isConstantCache = false;
    private boolean isConstantCached = false;
    public boolean isConstant() {
        if (!isConstantCached) {
            isConstantCache = isFinal()
                              && isVariable()
                              && getAttribute(idConstantValue) != null;
            isConstantCached = true;
        }
        return isConstantCache;
    }

    /**
     * Get the value
     */
    public Node getValue(Environment env) {
        if (isMethod()) {
            return null;
        }
        if (!isFinal()) {
            return null;
        }
        if (getValue() != null) {
            return (Expression)getValue();
        }
        byte data[] = getAttribute(idConstantValue);
        if (data == null) {
            return null;
        }

        try {
            BinaryConstantPool cpool = ((BinaryClass)getClassDefinition()).getConstants();
            // JVM 4.7.3 ConstantValue.constantvalue_index
            Object obj = cpool.getValue(new DataInputStream(new ByteArrayInputStream(data)).readUnsignedShort());
            switch (getType().getTypeCode()) {
              case TC_BOOLEAN:
                setValue(new BooleanExpression(0, ((Number)obj).intValue() != 0));
                break;
              case TC_BYTE:
              case TC_SHORT:
              case TC_CHAR:
              case TC_INT:
                setValue(new IntExpression(0, ((Number)obj).intValue()));
                break;
              case TC_LONG:
                setValue(new LongExpression(0, ((Number)obj).longValue()));
                break;
              case TC_FLOAT:
                setValue(new FloatExpression(0, ((Number)obj).floatValue()));
                break;
              case TC_DOUBLE:
                setValue(new DoubleExpression(0, ((Number)obj).doubleValue()));
                break;
              case TC_CLASS:
                setValue(new StringExpression(0, (String)cpool.getValue(((Number)obj).intValue())));
                break;
            }
            return (Expression)getValue();
        } catch (IOException e) {
            throw new CompilerError(e);
        }
    }

    /**
     * Get a field attribute
     */
    public byte[] getAttribute(Identifier name) {
        for (BinaryAttribute att = atts ; att != null ; att = att.next) {
            if (att.name.equals(name)) {
                return att.data;
            }
        }
        return null;
    }

    public boolean deleteAttribute(Identifier name) {
        BinaryAttribute walker = null, next = null;

        boolean succeed = false;

        while (atts.name.equals(name)) {
            atts = atts.next;
            succeed = true;
        }
        for (walker = atts; walker != null; walker = next) {
            next = walker.next;
            if (next != null) {
                if (next.name.equals(name)) {
                    walker.next = next.next;
                    next = next.next;
                    succeed = true;
                }
            }
        }
        for (walker = atts; walker != null; walker = walker.next) {
            if (walker.name.equals(name)) {
                throw new InternalError("Found attribute " + name);
            }
        }

        return succeed;
    }



    /*
     * Add an attribute to a field
     */
    public void addAttribute(Identifier name, byte data[], Environment env) {
        this.atts = new BinaryAttribute(name, data, this.atts);
        // Make sure that the new attribute is in the constant pool
        ((BinaryClass)(this.clazz)).cpool.indexString(name.toString(), env);
    }

}