org.hibernate.boot.model.naming.Identifier.java Source code

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Here is the source code for org.hibernate.boot.model.naming.Identifier.java

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/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */
package org.hibernate.boot.model.naming;

import java.util.Locale;

import org.hibernate.dialect.Dialect;
import org.hibernate.internal.util.StringHelper;

/**
 * Models an identifier (name), which may or may not be quoted.
 *
 * @author Steve Ebersole
 */
public class Identifier implements Comparable<Identifier> {
    private final String text;
    private final boolean isQuoted;

    /**
     * Means to generate an {@link Identifier} instance from its simple text form.
     * <p/>
     * If passed text is {@code null}, {@code null} is returned.
     * <p/>
     * If passed text is surrounded in quote markers, the generated Identifier
     * is considered quoted.  Quote markers include back-ticks (`), and
     * double-quotes (").
     *
     * @param text The text form
     *
     * @return The identifier form, or {@code null} if text was {@code null}
     */
    public static Identifier toIdentifier(String text) {
        if (StringHelper.isEmpty(text)) {
            return null;
        }
        final String trimmedText = text.trim();
        if (isQuoted(trimmedText)) {
            final String bareName = trimmedText.substring(1, trimmedText.length() - 1);
            return new Identifier(bareName, true);
        } else {
            return new Identifier(trimmedText, false);
        }
    }

    /**
     * Means to generate an {@link Identifier} instance from its simple text form.
     * <p/>
     * If passed text is {@code null}, {@code null} is returned.
     * <p/>
     * If passed text is surrounded in quote markers, the generated Identifier
     * is considered quoted.  Quote markers include back-ticks (`), and
     * double-quotes (").
     *
     * @param text The text form
     * @param quote Whether to quote unquoted text forms
     *
     * @return The identifier form, or {@code null} if text was {@code null}
     */
    public static Identifier toIdentifier(String text, boolean quote) {
        if (StringHelper.isEmpty(text)) {
            return null;
        }
        final String trimmedText = text.trim();
        if (isQuoted(trimmedText)) {
            final String bareName = trimmedText.substring(1, trimmedText.length() - 1);
            return new Identifier(bareName, true);
        } else {
            return new Identifier(trimmedText, quote);
        }
    }

    /**
     * Is the given identifier text considered quoted.  The following patterns are
     * recognized as quoted:<ul>
     *     <li>{@code `name`}</li>
     *     <li>{@code [name]}</li>
     *     <li>{@code "name"}</li>
     * </ul>
     * <p/>
     * That final form using double-quote (") is the JPA-defined quoting pattern.  Although
     * it is the standard, it makes for ugly declarations.
     *
     * @param name
     *
     * @return
     */
    public static boolean isQuoted(String name) {
        return (name.startsWith("`") && name.endsWith("`")) || (name.startsWith("[") && name.endsWith("]"))
                || (name.startsWith("\"") && name.endsWith("\""));
    }

    /**
     * Constructs an identifier instance.
     *
     * @param text The identifier text.
     * @param quoted Is this a quoted identifier?
     */
    public Identifier(String text, boolean quoted) {
        if (StringHelper.isEmpty(text)) {
            throw new IllegalIdentifierException("Identifier text cannot be null");
        }
        if (isQuoted(text)) {
            throw new IllegalIdentifierException("Identifier text should not contain quote markers (` or \")");
        }
        this.text = text;
        this.isQuoted = quoted;
    }

    /**
     * Constructs an unquoted identifier instance.
     *
     * @param text The identifier text.
     */
    protected Identifier(String text) {
        this.text = text;
        this.isQuoted = false;
    }

    /**
     * Get the identifiers name (text)
     *
     * @return The name
     */
    public String getText() {
        return text;
    }

    /**
     * Is this a quoted identifier>
     *
     * @return True if this is a quote identifier; false otherwise.
     */
    public boolean isQuoted() {
        return isQuoted;
    }

    /**
     * If this is a quoted identifier, then return the identifier name
     * enclosed in dialect-specific open- and end-quotes; otherwise,
     * simply return the unquoted identifier.
     *
     * @param dialect The dialect whose dialect-specific quoting should be used.
     *
     * @return if quoted, identifier name enclosed in dialect-specific open- and
     * end-quotes; otherwise, the unquoted identifier.
     */
    public String render(Dialect dialect) {
        return isQuoted ? String.valueOf(dialect.openQuote()) + getText() + dialect.closeQuote() : getText();
    }

    public String render() {
        return isQuoted ? '`' + getText() + '`' : getText();
    }

    public String getCanonicalName() {
        return isQuoted ? text : text.toLowerCase(Locale.ENGLISH);
    }

    @Override
    public String toString() {
        return render();
    }

    @Override
    public boolean equals(Object o) {
        if (!(o instanceof Identifier)) {
            return false;
        }

        final Identifier that = (Identifier) o;
        return getCanonicalName().equals(that.getCanonicalName());
    }

    @Override
    public int hashCode() {
        return isQuoted ? text.hashCode() : text.toLowerCase(Locale.ENGLISH).hashCode();
    }

    public static boolean areEqual(Identifier id1, Identifier id2) {
        if (id1 == null) {
            return id2 == null;
        } else {
            return id1.equals(id2);
        }
    }

    public static Identifier quote(Identifier identifier) {
        return identifier.isQuoted() ? identifier : Identifier.toIdentifier(identifier.getText(), true);
    }

    @Override
    public int compareTo(Identifier o) {
        return getCanonicalName().compareTo(o.getCanonicalName());
    }
}