RC9/qpid/java/common/src/main/java/org/apache/qpid/transport/util/Functions.java

/*
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
 */
package org.apache.qpid.transport.util;

import java.nio.ByteBuffer;

import static java.lang.Math.*;


/**
 * Functions
 *
 * @author Rafael H. Schloming
 */

public class Functions
{

    public static final int mod(int n, int m)
    {
        int r = n % m;
        return r < 0 ? m + r : r;
    }

    public static final byte lsb(int i)
    {
        return (byte) (0xFF & i);
    }

    public static final byte lsb(long l)
    {
        return (byte) (0xFF & l);
    }

    public static final String str(ByteBuffer buf)
    {
        return str(buf, buf.remaining());
    }

    public static final String str(ByteBuffer buf, int limit)
    {
        StringBuilder str = new StringBuilder();
        str.append('"');

        for (int i = 0; i < min(buf.remaining(), limit); i++)
        {
            byte c = buf.get(buf.position() + i);

            if (c > 31 && c < 127 && c != '\\')
            {
                str.append((char)c);
            }
            else
            {
                str.append(String.format("\\x%02x", c));
            }
        }

        str.append('"');

        if (limit < buf.remaining())
        {
            str.append("...");
        }

        return str.toString();
    }

    public static final String str(byte[] bytes)
    {
        return str(ByteBuffer.wrap(bytes));
    }

    public static final String str(byte[] bytes, int limit)
    {
        return str(ByteBuffer.wrap(bytes), limit);
    }

}