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Diffstat (limited to 'src/main/java/org/apache/commons/math3/util/DefaultTransformer.java')
-rw-r--r-- | src/main/java/org/apache/commons/math3/util/DefaultTransformer.java | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/src/main/java/org/apache/commons/math3/util/DefaultTransformer.java b/src/main/java/org/apache/commons/math3/util/DefaultTransformer.java new file mode 100644 index 0000000..ba92d1b --- /dev/null +++ b/src/main/java/org/apache/commons/math3/util/DefaultTransformer.java @@ -0,0 +1,79 @@ +/* + * 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.commons.math3.util; + +import org.apache.commons.math3.exception.MathIllegalArgumentException; +import org.apache.commons.math3.exception.NullArgumentException; +import org.apache.commons.math3.exception.util.LocalizedFormats; + +import java.io.Serializable; + +/** + * A Default NumberTransformer for java.lang.Numbers and Numeric Strings. This provides some simple + * conversion capabilities to turn any java.lang.Number into a primitive double or to turn a String + * representation of a Number into a double. + */ +public class DefaultTransformer implements NumberTransformer, Serializable { + + /** Serializable version identifier */ + private static final long serialVersionUID = 4019938025047800455L; + + /** + * @param o the object that gets transformed. + * @return a double primitive representation of the Object o. + * @throws NullArgumentException if Object <code>o</code> is {@code null}. + * @throws MathIllegalArgumentException if Object <code>o</code> cannot successfully be + * transformed + * @see <a + * href="http://commons.apache.org/collections/api-release/org/apache/commons/collections/Transformer.html">Commons + * Collections Transformer</a> + */ + public double transform(Object o) throws NullArgumentException, MathIllegalArgumentException { + + if (o == null) { + throw new NullArgumentException(LocalizedFormats.OBJECT_TRANSFORMATION); + } + + if (o instanceof Number) { + return ((Number) o).doubleValue(); + } + + try { + return Double.parseDouble(o.toString()); + } catch (NumberFormatException e) { + throw new MathIllegalArgumentException( + LocalizedFormats.CANNOT_TRANSFORM_TO_DOUBLE, o.toString()); + } + } + + /** {@inheritDoc} */ + @Override + public boolean equals(Object other) { + if (this == other) { + return true; + } + return other instanceof DefaultTransformer; + } + + /** {@inheritDoc} */ + @Override + public int hashCode() { + // some arbitrary number ... + return 401993047; + } +} |