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Diffstat (limited to 'qpid/java/common/src/main/java/org/apache/qpid/util/Serial.java')
-rw-r--r-- | qpid/java/common/src/main/java/org/apache/qpid/util/Serial.java | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/qpid/java/common/src/main/java/org/apache/qpid/util/Serial.java b/qpid/java/common/src/main/java/org/apache/qpid/util/Serial.java new file mode 100644 index 0000000000..8ad9d00f54 --- /dev/null +++ b/qpid/java/common/src/main/java/org/apache/qpid/util/Serial.java @@ -0,0 +1,108 @@ +package org.apache.qpid.util; +/* + * + * 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. + * + */ + + +import java.util.Comparator; + +import org.apache.qpid.SerialException; + +/** + * This class provides basic serial number comparisons as defined in + * RFC 1982. + */ + +public class Serial +{ + + public static final Comparator<Integer> COMPARATOR = new Comparator<Integer>() + { + public int compare(Integer s1, Integer s2) + { + return Serial.compare(s1, s2); + } + }; + + /** + * Compares two numbers using serial arithmetic. + * + * @param s1 the first serial number + * @param s2 the second serial number + * + * @return a negative integer, zero, or a positive integer as the + * first argument is less than, equal to, or greater than the + * second + */ + public static final int compare(int s1, int s2) + { + return s1 - s2; + } + + public static final boolean lt(int s1, int s2) + { + return compare(s1, s2) < 0; + } + + public static final boolean le(int s1, int s2) + { + return compare(s1, s2) <= 0; + } + + public static final boolean gt(int s1, int s2) + { + return compare(s1, s2) > 0; + } + + public static final boolean ge(int s1, int s2) + { + return compare(s1, s2) >= 0; + } + + public static final boolean eq(int s1, int s2) + { + return s1 == s2; + } + + public static final int min(int s1, int s2) + { + if (lt(s1, s2)) + { + return s1; + } + else + { + return s2; + } + } + + public static final int max(int s1, int s2) + { + if (gt(s1, s2)) + { + return s1; + } + else + { + return s2; + } + } + +} |