META-INF.modules.java.desktop.classes.java.awt.font.LineMetrics Maven / Gradle / Ivy
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* by Oracle in the LICENSE file that accompanied this code.
*
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* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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package java.awt.font;
/**
* The {@code LineMetrics} class allows access to the
* metrics needed to layout characters along a line
* and to layout of a set of lines. A {@code LineMetrics}
* object encapsulates the measurement information associated
* with a run of text.
*
* Fonts can have different metrics for different ranges of
* characters. The {@code getLineMetrics} methods of
* {@link java.awt.Font Font} take some text as an argument
* and return a {@code LineMetrics} object describing the
* metrics of the initial number of characters in that text, as
* returned by {@link #getNumChars}.
*/
public abstract class LineMetrics {
/**
* Returns the number of characters ({@code char} values) in the text whose
* metrics are encapsulated by this {@code LineMetrics}
* object.
* @return the number of characters ({@code char} values) in the text with which
* this {@code LineMetrics} was created.
*/
public abstract int getNumChars();
/**
* Returns the ascent of the text. The ascent
* is the distance from the baseline
* to the ascender line. The ascent usually represents the
* the height of the capital letters of the text. Some characters
* can extend above the ascender line.
* @return the ascent of the text.
*/
public abstract float getAscent();
/**
* Returns the descent of the text. The descent
* is the distance from the baseline
* to the descender line. The descent usually represents
* the distance to the bottom of lower case letters like
* 'p'. Some characters can extend below the descender
* line.
* @return the descent of the text.
*/
public abstract float getDescent();
/**
* Returns the leading of the text. The
* leading is the recommended
* distance from the bottom of the descender line to the
* top of the next line.
* @return the leading of the text.
*/
public abstract float getLeading();
/**
* Returns the height of the text. The
* height is equal to the sum of the ascent, the
* descent and the leading.
* @return the height of the text.
*/
public abstract float getHeight();
/**
* Returns the baseline index of the text.
* The index is one of
* {@link java.awt.Font#ROMAN_BASELINE ROMAN_BASELINE},
* {@link java.awt.Font#CENTER_BASELINE CENTER_BASELINE},
* {@link java.awt.Font#HANGING_BASELINE HANGING_BASELINE}.
* @return the baseline of the text.
*/
public abstract int getBaselineIndex();
/**
* Returns the baseline offsets of the text,
* relative to the baseline of the text. The
* offsets are indexed by baseline index. For
* example, if the baseline index is
* {@code CENTER_BASELINE} then
* {@code offsets[HANGING_BASELINE]} is usually
* negative, {@code offsets[CENTER_BASELINE]}
* is zero, and {@code offsets[ROMAN_BASELINE]}
* is usually positive.
* @return the baseline offsets of the text.
*/
public abstract float[] getBaselineOffsets();
/**
* Returns the position of the strike-through line
* relative to the baseline.
* @return the position of the strike-through line.
*/
public abstract float getStrikethroughOffset();
/**
* Returns the thickness of the strike-through line.
* @return the thickness of the strike-through line.
*/
public abstract float getStrikethroughThickness();
/**
* Returns the position of the underline relative to
* the baseline.
* @return the position of the underline.
*/
public abstract float getUnderlineOffset();
/**
* Returns the thickness of the underline.
* @return the thickness of the underline.
*/
public abstract float getUnderlineThickness();
}