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 * The Universal Permissive License (UPL), Version 1.0
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 * person obtaining a copy of this software, associated documentation and/or
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 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.js.parser;

import java.util.HashMap;

A name space hierarchy, where each level holds a name directory with names that may be unique for
each level.
/**
 * A name space hierarchy, where each level holds a name directory with names that may be unique for
 * each level.
 */

public class Namespace {
    
Parent namespace. /** Parent namespace. */
    private final Namespace parent;

    
Name directory - version count for each name /** Name directory - version count for each name */
    private final HashMap<String, Integer> directory;

    
Constructor
/**
     * Constructor
     */
    public Namespace() {
        this(null);
    }

    
Constructor
Params:
parent – parent name space/**
     * Constructor
     *
     * @param parent parent name space
     */
    public Namespace(final Namespace parent) {
        this.parent = parent;
        this.directory = new HashMap<>();
    }

    
Return the parent Namespace of this space.
Returns:
parent name space/**
     * Return the parent Namespace of this space.
     *
     * @return parent name space
     */
    public Namespace getParent() {
        return parent;
    }

    
Create a uniqueName name in the namespace in the form base$n where n varies .
Params:
base – Base of name. Base will be returned if uniqueName.
Returns:
Generated uniqueName name./**
     * Create a uniqueName name in the namespace in the form base$n where n varies .
     *
     * @param base Base of name. Base will be returned if uniqueName.
     *
     * @return Generated uniqueName name.
     */
    public String uniqueName(final String base) {
        for (Namespace namespace = this; namespace != null; namespace = namespace.getParent()) {
            final HashMap<String, Integer> namespaceDirectory = namespace.directory;
            final Integer counter = namespaceDirectory.get(base);

            if (counter != null) {
                final int count = counter + 1;
                namespaceDirectory.put(base, count);
                return base + '-' + count;
            }
        }

        directory.put(base, 0);

        return base;
    }

    @Override
    public String toString() {
        return directory.toString();
    }
}