QualifiedName.java

/*
*****************************************************************
Copyright (c) 2014-2015 Jeff Martin, Tim Bacon
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package org.custommonkey.xmlunit;

/**
 * Since javax.xml.namespace.QName is not present prior to Java5, this
 * is XMLUnit's own abstraction.
 */
public final class QualifiedName {
    private final String namespaceUri;
    private final String localName;

    public QualifiedName(String localName) {
        this(XMLConstants.NULL_NS_URI, localName);
    }

    public QualifiedName(String namespaceUri, String localName) {
        if (localName == null) {
            throw new IllegalArgumentException("localName must not be null");
        }
        this.namespaceUri =
            namespaceUri == null ? XMLConstants.NULL_NS_URI : namespaceUri;
        this.localName = localName;
    }

    public String getNamespaceURI() {
        return namespaceUri;
    }

    public String getLocalName() {
        return localName;
    }

    public int hashCode() {
        return 7 * namespaceUri.hashCode() + localName.hashCode();
    }

    public boolean equals(Object o) {
        if (!(o instanceof QualifiedName)) {
            return false;
        }
        QualifiedName other = (QualifiedName) o;
        return namespaceUri.equals(other.namespaceUri)
            && localName.equals(other.localName);
    }

    /**
     * Parses strings of the form "{NS-URI}LOCAL-NAME" or "prefix:localName" as QualifiedNames.
     *
     * <p>When using the prefix-version the prefix must be defined
     * inside the current NamespaceContext.</p>
     *
     * @see XMLUnit#setXpathNamespaceContext
     */
    public static QualifiedName valueOf(String value) {
        return valueOf(value, XMLUnit.getXpathNamespaceContext());
    }

    /**
     * Represents the QualifiedName as {NS-URI}LOCAL-NAME.
     *
     * <p>If the NS-URI is equal to NULL_NS_URI only the local name is returned.</p>
     */
    public String toString() {
        return XMLConstants.NULL_NS_URI.equals(namespaceUri) ?
            localName : "{" + namespaceUri + "}" + localName;
    }

    /**
     * Parses strings of the form "{NS-URI}LOCAL-NAME" or "prefix:localName" as QualifiedNames.
     *
     * <p>When using the prefix-version the prefix must be defined
     * inside the NamespaceContext given as argument.</p>
     */
    public static QualifiedName valueOf(String value, NamespaceContext ctx) {
        if (value == null) {
            throw new IllegalArgumentException("value must not be null");
        }
        int colon = value.indexOf(':');
        int closingBrace = value.indexOf('}');
        boolean qnameToStringStyle = value.startsWith("{") && closingBrace > 0;
        if (!qnameToStringStyle && colon < 0) {
            return new QualifiedName(value); // null namespace
        }
        return qnameToStringStyle ? parseQNameToString(value, closingBrace)
            : parsePrefixFormat(value, colon, ctx);
    }

    private static QualifiedName parseQNameToString(String value, int closingBrace) {
        if (closingBrace + 1 == value.length()) {
            throw new IllegalArgumentException("localName must not be empty in "
                                               + value);
        }
        return new QualifiedName(value.substring(1, closingBrace),
                                 value.substring(closingBrace + 1));
    }

    private static QualifiedName parsePrefixFormat(String value, int colon,
                                                   NamespaceContext ctx) {
        if (colon + 1 == value.length()) {
            throw new IllegalArgumentException("localName must not be empty in "
                                               + value);
        }
        if (ctx == null) {
            throw new IllegalArgumentException("Cannot parse " + value
                                               + " without a NamespaceContext");
        }
        String prefix = value.substring(0, colon);
        String nsUri = ctx.getNamespaceURI(prefix);
        if (nsUri == null) {
            throw new IllegalArgumentException(prefix + " is unknown to "
                                               + "NamespaceContext");
        }
        return new QualifiedName(nsUri, value.substring(colon + 1));
    }
}