LocalizedAssert.java

package org.identityconnectors.dbcommon;

import org.identityconnectors.framework.common.objects.ConnectorMessages;

/**
 * Localized asserts is a set of localized asserts utility method that throws
 * localized exception when assert is not true. Argument names passed into
 * assert methods can also be localized
 *
 * @author kitko
 *
 */
public class LocalizedAssert {

    private final ConnectorMessages cm;
    private boolean localizeArguments;

    /**
     * Creates asserts with messages.
     *
     * @param cm
     * @throws IllegalArgumentException
     *             if cm param is null
     */
    public LocalizedAssert(final ConnectorMessages cm) {
        if (cm == null) {
            throw new IllegalArgumentException("ConnectorMessages argument is null");
        }
        this.cm = cm;
    }

    /**
     * Creates asserts with messages with flag whether to localize argument
     * names
     *
     * @param cm
     * @param localizeArguments
     *            the arg
     * @throws IllegalArgumentException
     *             if cm param is null
     */
    public LocalizedAssert(final ConnectorMessages cm, boolean localizeArguments) {
        if (cm == null) {
            throw new IllegalArgumentException("ConnectorMessages argument is null");
        }
        this.cm = cm;
        this.localizeArguments = localizeArguments;
    }

    private void throwException(String locKey, String argument) {
        if (localizeArguments) {
            argument = cm.format(argument, argument);
        }
        String msg = cm.format(locKey, null, argument);
        throw new IllegalArgumentException(msg);
    }

    /**
     * Asserts the argument is not null.
     *
     * If argument is null, throws localized IllegalArgumentException
     *
     * @param <T>
     * @param o
     * @param argument
     * @return o param
     */
    public <T> T assertNotNull(T o, String argument) {
        if (o == null) {
            throwException(DBMessages.ASSERT_NOT_NULL, argument);
        }
        return o;
    }

    /**
     * Asserts the argument is null.
     *
     * If argument is not null, throws localized IllegalArgumentException
     *
     * @param <T>
     * @param o
     * @param argument
     * @return o
     */
    public <T> T assertNull(T o, String argument) {
        if (o != null) {
            throwException(DBMessages.ASSERT_NULL, argument);
        }
        return o;
    }

    /**
     * Asserts that argument string is not blank.
     *
     * If argument is null or blank, throws localized IllegalArgumentException
     *
     * @param o
     * @param argument
     * @return same string
     */
    public String assertNotBlank(String o, String argument) {
        if (o == null || o.length() == 0) {
            throwException(DBMessages.ASSERT_NOT_BLANK, argument);
        }
        return o;
    }

    /**
     * Asserts that argument string is blank.
     *
     * If argument is not blank, throws localized IllegalArgumentException
     *
     * @param s
     * @param argument
     * @return same string
     */
    public String assertBlank(String s, String argument) {
        if (s != null && s.length() > 0) {
            throwException(DBMessages.ASSERT_BLANK, argument);
        }
        return s;
    }

}