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/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed 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 android.util;
import static com.android.internal.util.Preconditions.checkNotNull;
import static com.android.internal.util.Preconditions.checkArgumentFinite;
/**
* Immutable class for describing width and height dimensions in some arbitrary
* unit.
*
* Width and height are finite values stored as a floating point representation.
*
*/
public final class SizeF {
/**
* Create a new immutable SizeF instance.
*
* Both the {@code width} and the {@code height} must be a finite number.
* In particular, {@code NaN} and positive/negative infinity are illegal values.
*
* @param width The width of the size
* @param height The height of the size
*
* @throws IllegalArgumentException
* if either {@code width} or {@code height} was not finite.
*/
public SizeF(final float width, final float height) {
mWidth = checkArgumentFinite(width, "width");
mHeight = checkArgumentFinite(height, "height");
}
/**
* Get the width of the size (as an arbitrary unit).
* @return width
*/
public float getWidth() {
return mWidth;
}
/**
* Get the height of the size (as an arbitrary unit).
* @return height
*/
public float getHeight() {
return mHeight;
}
/**
* Check if this size is equal to another size.
*
* Two sizes are equal if and only if both their widths and heights are the same.
*
* For this purpose, the width/height float values are considered to be the same if and only
* if the method {@link Float#floatToIntBits(float)} returns the identical {@code int} value
* when applied to each.
*
* @return {@code true} if the objects were equal, {@code false} otherwise
*/
@Override
public boolean equals(final Object obj) {
if (obj == null) {
return false;
}
if (this == obj) {
return true;
}
if (obj instanceof SizeF) {
final SizeF other = (SizeF) obj;
return mWidth == other.mWidth && mHeight == other.mHeight;
}
return false;
}
/**
* Return the size represented as a string with the format {@code "WxH"}
*
* @return string representation of the size
*/
@Override
public String toString() {
return mWidth + "x" + mHeight;
}
private static NumberFormatException invalidSizeF(String s) {
throw new NumberFormatException("Invalid SizeF: \"" + s + "\"");
}
/**
* Parses the specified string as a size value.
*
* The ASCII characters {@code \}{@code u002a} ('*') and
* {@code \}{@code u0078} ('x') are recognized as separators between
* the width and height.
*
* For any {@code SizeF s}: {@code SizeF.parseSizeF(s.toString()).equals(s)}.
* However, the method also handles sizes expressed in the
* following forms:
*
* "width{@code x}height" or
* "width{@code *}height" {@code => new SizeF(width, height)},
* where width and height are string floats potentially
* containing a sign, such as "-10.3", "+7" or "5.2", but not containing
* an {@code 'x'} (such as a float in hexadecimal string format).
*
* {@code
* SizeF.parseSizeF("3.2*+6").equals(new SizeF(3.2f, 6.0f)) == true
* SizeF.parseSizeF("-3x-6").equals(new SizeF(-3.0f, -6.0f)) == true
* SizeF.parseSizeF("4 by 3") => throws NumberFormatException
* }
*
* @param string the string representation of a size value.
* @return the size value represented by {@code string}.
*
* @throws NumberFormatException if {@code string} cannot be parsed
* as a size value.
* @throws NullPointerException if {@code string} was {@code null}
*/
public static SizeF parseSizeF(String string)
throws NumberFormatException {
checkNotNull(string, "string must not be null");
int sep_ix = string.indexOf('*');
if (sep_ix < 0) {
sep_ix = string.indexOf('x');
}
if (sep_ix < 0) {
throw invalidSizeF(string);
}
try {
return new SizeF(Float.parseFloat(string.substring(0, sep_ix)),
Float.parseFloat(string.substring(sep_ix + 1)));
} catch (NumberFormatException e) {
throw invalidSizeF(string);
} catch (IllegalArgumentException e) {
throw invalidSizeF(string);
}
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
return Float.floatToIntBits(mWidth) ^ Float.floatToIntBits(mHeight);
}
private final float mWidth;
private final float mHeight;
}