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src/java.desktop/share/classes/javax/swing/Spring.java
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*** 25,40 ****
package javax.swing;
import java.awt.Component;
/**
! * An instance of the <code>Spring</code> class holds three properties that
* characterize its behavior: the <em>minimum</em>, <em>preferred</em>, and
* <em>maximum</em> values. Each of these properties may be involved in
* defining its fourth, <em>value</em>, property based on a series of rules.
* <p>
! * An instance of the <code>Spring</code> class can be visualized as a
* mechanical spring that provides a corrective force as the spring is compressed
* or stretched away from its preferred value. This force is modelled
* as linear function of the distance from the preferred value, but with
* two different constants -- one for the compressional force and one for the
* tensional one. Those constants are specified by the minimum and maximum
--- 25,40 ----
package javax.swing;
import java.awt.Component;
/**
! * An instance of the {@code Spring} class holds three properties that
* characterize its behavior: the <em>minimum</em>, <em>preferred</em>, and
* <em>maximum</em> values. Each of these properties may be involved in
* defining its fourth, <em>value</em>, property based on a series of rules.
* <p>
! * An instance of the {@code Spring} class can be visualized as a
* mechanical spring that provides a corrective force as the spring is compressed
* or stretched away from its preferred value. This force is modelled
* as linear function of the distance from the preferred value, but with
* two different constants -- one for the compressional force and one for the
* tensional one. Those constants are specified by the minimum and maximum
*** 42,95 ****
* equal and opposite force to that which is created when it is at its
* maximum value. The difference between the <em>preferred</em> and
* <em>minimum</em> values, therefore, represents the ease with which the
* spring can be compressed and the difference between its <em>maximum</em>
* and <em>preferred</em> values, indicates the ease with which the
! * <code>Spring</code> can be extended.
* See the {@link #sum} method for details.
*
* <p>
! * By defining simple arithmetic operations on <code>Spring</code>s,
! * the behavior of a collection of <code>Spring</code>s
! * can be reduced to that of an ordinary (non-compound) <code>Spring</code>. We define
* the "+", "-", <em>max</em>, and <em>min</em> operators on
! * <code>Spring</code>s so that, in each case, the result is a <code>Spring</code>
* whose characteristics bear a useful mathematical relationship to its constituent
* springs.
*
* <p>
! * A <code>Spring</code> can be treated as a pair of intervals
* with a single common point: the preferred value.
* The following rules define some of the
* arithmetic operators that can be applied to intervals
! * (<code>[a, b]</code> refers to the interval
! * from <code>a</code>
! * to <code>b</code>,
! * where <code>a <= b</code>).
*
* <pre>
* [a1, b1] + [a2, b2] = [a1 + a2, b1 + b2]
*
* -[a, b] = [-b, -a]
*
* max([a1, b1], [a2, b2]) = [max(a1, a2), max(b1, b2)]
* </pre>
* <p>
*
! * If we denote <code>Spring</code>s as <code>[a, b, c]</code>,
! * where <code>a <= b <= c</code>, we can define the same
! * arithmetic operators on <code>Spring</code>s:
*
* <pre>
* [a1, b1, c1] + [a2, b2, c2] = [a1 + a2, b1 + b2, c1 + c2]
*
* -[a, b, c] = [-c, -b, -a]
*
* max([a1, b1, c1], [a2, b2, c2]) = [max(a1, a2), max(b1, b2), max(c1, c2)]
* </pre>
* <p>
! * With both intervals and <code>Spring</code>s we can define "-" and <em>min</em>
* in terms of negation:
*
* <pre>
* X - Y = X + (-Y)
*
--- 42,95 ----
* equal and opposite force to that which is created when it is at its
* maximum value. The difference between the <em>preferred</em> and
* <em>minimum</em> values, therefore, represents the ease with which the
* spring can be compressed and the difference between its <em>maximum</em>
* and <em>preferred</em> values, indicates the ease with which the
! * {@code Spring} can be extended.
* See the {@link #sum} method for details.
*
* <p>
! * By defining simple arithmetic operations on {@code Spring}s,
! * the behavior of a collection of {@code Spring}s
! * can be reduced to that of an ordinary (non-compound) {@code Spring}. We define
* the "+", "-", <em>max</em>, and <em>min</em> operators on
! * {@code Spring}s so that, in each case, the result is a {@code Spring}
* whose characteristics bear a useful mathematical relationship to its constituent
* springs.
*
* <p>
! * A {@code Spring} can be treated as a pair of intervals
* with a single common point: the preferred value.
* The following rules define some of the
* arithmetic operators that can be applied to intervals
! * ({@code [a, b]} refers to the interval
! * from {@code a}
! * to {@code b},
! * where {@code a <= b}).
*
* <pre>
* [a1, b1] + [a2, b2] = [a1 + a2, b1 + b2]
*
* -[a, b] = [-b, -a]
*
* max([a1, b1], [a2, b2]) = [max(a1, a2), max(b1, b2)]
* </pre>
* <p>
*
! * If we denote {@code Spring}s as {@code [a, b, c]},
! * where {@code a <= b <= c}, we can define the same
! * arithmetic operators on {@code Spring}s:
*
* <pre>
* [a1, b1, c1] + [a2, b2, c2] = [a1 + a2, b1 + b2, c1 + c2]
*
* -[a, b, c] = [-c, -b, -a]
*
* max([a1, b1, c1], [a2, b2, c2]) = [max(a1, a2), max(b1, b2), max(c1, c2)]
* </pre>
* <p>
! * With both intervals and {@code Spring}s we can define "-" and <em>min</em>
* in terms of negation:
*
* <pre>
* X - Y = X + (-Y)
*
*** 98,114 ****
* <p>
* For the static methods in this class that embody the arithmetic
* operators, we do not actually perform the operation in question as
* that would snapshot the values of the properties of the method's arguments
* at the time the static method is called. Instead, the static methods
! * create a new <code>Spring</code> instance containing references to
* the method's arguments so that the characteristics of the new spring track the
* potentially changing characteristics of the springs from which it
* was made. This is a little like the idea of a <em>lazy value</em>
* in a functional language.
* <p>
! * If you are implementing a <code>SpringLayout</code> you
* can find further information and examples in
* <a
href="http://docs.oracle.com/javase/tutorial/uiswing/layout/spring.html">How to Use SpringLayout</a>,
* a section in <em>The Java Tutorial.</em>
* <p>
--- 98,114 ----
* <p>
* For the static methods in this class that embody the arithmetic
* operators, we do not actually perform the operation in question as
* that would snapshot the values of the properties of the method's arguments
* at the time the static method is called. Instead, the static methods
! * create a new {@code Spring} instance containing references to
* the method's arguments so that the characteristics of the new spring track the
* potentially changing characteristics of the springs from which it
* was made. This is a little like the idea of a <em>lazy value</em>
* in a functional language.
* <p>
! * If you are implementing a {@code SpringLayout} you
* can find further information and examples in
* <a
href="http://docs.oracle.com/javase/tutorial/uiswing/layout/spring.html">How to Use SpringLayout</a>,
* a section in <em>The Java Tutorial.</em>
* <p>
*** 116,126 ****
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeans™
! * has been added to the <code>java.beans</code> package.
* Please see {@link java.beans.XMLEncoder}.
*
* @see SpringLayout
* @see SpringLayout.Constraints
*
--- 116,126 ----
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeans™
! * has been added to the {@code java.beans} package.
* Please see {@link java.beans.XMLEncoder}.
*
* @see SpringLayout
* @see SpringLayout.Constraints
*
*** 134,144 ****
* An integer value signifying that a property value has not yet been calculated.
*/
public static final int UNSET = Integer.MIN_VALUE;
/**
! * Used by factory methods to create a <code>Spring</code>.
*
* @see #constant(int)
* @see #constant(int, int, int)
* @see #max
* @see #minus
--- 134,144 ----
* An integer value signifying that a property value has not yet been calculated.
*/
public static final int UNSET = Integer.MIN_VALUE;
/**
! * Used by factory methods to create a {@code Spring}.
*
* @see #constant(int)
* @see #constant(int, int, int)
* @see #max
* @see #minus
*** 146,188 ****
* @see SpringLayout.Constraints
*/
protected Spring() {}
/**
! * Returns the <em>minimum</em> value of this <code>Spring</code>.
*
! * @return the <code>minimumValue</code> property of this <code>Spring</code>
*/
public abstract int getMinimumValue();
/**
! * Returns the <em>preferred</em> value of this <code>Spring</code>.
*
! * @return the <code>preferredValue</code> of this <code>Spring</code>
*/
public abstract int getPreferredValue();
/**
! * Returns the <em>maximum</em> value of this <code>Spring</code>.
*
! * @return the <code>maximumValue</code> property of this <code>Spring</code>
*/
public abstract int getMaximumValue();
/**
! * Returns the current <em>value</em> of this <code>Spring</code>.
*
! * @return the <code>value</code> property of this <code>Spring</code>
*
* @see #setValue
*/
public abstract int getValue();
/**
! * Sets the current <em>value</em> of this <code>Spring</code> to <code>value</code>.
*
! * @param value the new setting of the <code>value</code> property
*
* @see #getValue
*/
public abstract void setValue(int value);
--- 146,188 ----
* @see SpringLayout.Constraints
*/
protected Spring() {}
/**
! * Returns the <em>minimum</em> value of this {@code Spring}.
*
! * @return the {@code minimumValue} property of this {@code Spring}
*/
public abstract int getMinimumValue();
/**
! * Returns the <em>preferred</em> value of this {@code Spring}.
*
! * @return the {@code preferredValue} of this {@code Spring}
*/
public abstract int getPreferredValue();
/**
! * Returns the <em>maximum</em> value of this {@code Spring}.
*
! * @return the {@code maximumValue} property of this {@code Spring}
*/
public abstract int getMaximumValue();
/**
! * Returns the current <em>value</em> of this {@code Spring}.
*
! * @return the {@code value} property of this {@code Spring}
*
* @see #setValue
*/
public abstract int getValue();
/**
! * Sets the current <em>value</em> of this {@code Spring} to {@code value}.
*
! * @param value the new setting of the {@code value} property
*
* @see #getValue
*/
public abstract void setValue(int value);
*** 512,545 ****
}
}
/**
* Returns a strut -- a spring whose <em>minimum</em>, <em>preferred</em>, and
! * <em>maximum</em> values each have the value <code>pref</code>.
*
* @param pref the <em>minimum</em>, <em>preferred</em>, and
* <em>maximum</em> values of the new spring
* @return a spring whose <em>minimum</em>, <em>preferred</em>, and
! * <em>maximum</em> values each have the value <code>pref</code>
*
* @see Spring
*/
public static Spring constant(int pref) {
return constant(pref, pref, pref);
}
/**
* Returns a spring whose <em>minimum</em>, <em>preferred</em>, and
! * <em>maximum</em> values have the values: <code>min</code>, <code>pref</code>,
! * and <code>max</code> respectively.
*
* @param min the <em>minimum</em> value of the new spring
* @param pref the <em>preferred</em> value of the new spring
* @param max the <em>maximum</em> value of the new spring
* @return a spring whose <em>minimum</em>, <em>preferred</em>, and
! * <em>maximum</em> values have the values: <code>min</code>, <code>pref</code>,
! * and <code>max</code> respectively
*
* @see Spring
*/
public static Spring constant(int min, int pref, int max) {
return new StaticSpring(min, pref, max);
--- 512,545 ----
}
}
/**
* Returns a strut -- a spring whose <em>minimum</em>, <em>preferred</em>, and
! * <em>maximum</em> values each have the value {@code pref}.
*
* @param pref the <em>minimum</em>, <em>preferred</em>, and
* <em>maximum</em> values of the new spring
* @return a spring whose <em>minimum</em>, <em>preferred</em>, and
! * <em>maximum</em> values each have the value {@code pref}
*
* @see Spring
*/
public static Spring constant(int pref) {
return constant(pref, pref, pref);
}
/**
* Returns a spring whose <em>minimum</em>, <em>preferred</em>, and
! * <em>maximum</em> values have the values: {@code min}, {@code pref},
! * and {@code max} respectively.
*
* @param min the <em>minimum</em> value of the new spring
* @param pref the <em>preferred</em> value of the new spring
* @param max the <em>maximum</em> value of the new spring
* @return a spring whose <em>minimum</em>, <em>preferred</em>, and
! * <em>maximum</em> values have the values: {@code min}, {@code pref},
! * and {@code max} respectively
*
* @see Spring
*/
public static Spring constant(int min, int pref, int max) {
return new StaticSpring(min, pref, max);
*** 557,569 ****
public static Spring minus(Spring s) {
return new NegativeSpring(s);
}
/**
! * Returns <code>s1+s2</code>: a spring representing <code>s1</code> and <code>s2</code>
! * in series. In a sum, <code>s3</code>, of two springs, <code>s1</code> and <code>s2</code>,
! * the <em>strains</em> of <code>s1</code>, <code>s2</code>, and <code>s3</code> are maintained
* at the same level (to within the precision implied by their integer <em>value</em>s).
* The strain of a spring in compression is:
* <pre>
* value - pref
* ------------
--- 557,569 ----
public static Spring minus(Spring s) {
return new NegativeSpring(s);
}
/**
! * Returns {@code s1+s2}: a spring representing {@code s1} and {@code s2}
! * in series. In a sum, {@code s3}, of two springs, {@code s1} and {@code s2},
! * the <em>strains</em> of {@code s1}, {@code s2}, and {@code s3} are maintained
* at the same level (to within the precision implied by their integer <em>value</em>s).
* The strain of a spring in compression is:
* <pre>
* value - pref
* ------------
*** 573,593 ****
* <pre>
* value - pref
* ------------
* max - pref
* </pre>
! * When <code>setValue</code> is called on the sum spring, <code>s3</code>, the strain
! * in <code>s3</code> is calculated using one of the formulas above. Once the strain of
! * the sum is known, the <em>value</em>s of <code>s1</code> and <code>s2</code> are
* then set so that they are have a strain equal to that of the sum. The formulas are
* evaluated so as to take rounding errors into account and ensure that the sum of
! * the <em>value</em>s of <code>s1</code> and <code>s2</code> is exactly equal to
! * the <em>value</em> of <code>s3</code>.
*
* @param s1 a {@code Spring} object
* @param s2 a {@code Spring} object
! * @return <code>s1+s2</code>: a spring representing <code>s1</code> and <code>s2</code> in series
*
* @see Spring
*/
public static Spring sum(Spring s1, Spring s2) {
return new SumSpring(s1, s2);
--- 573,593 ----
* <pre>
* value - pref
* ------------
* max - pref
* </pre>
! * When {@code setValue} is called on the sum spring, {@code s3}, the strain
! * in {@code s3} is calculated using one of the formulas above. Once the strain of
! * the sum is known, the <em>value</em>s of {@code s1} and {@code s2} are
* then set so that they are have a strain equal to that of the sum. The formulas are
* evaluated so as to take rounding errors into account and ensure that the sum of
! * the <em>value</em>s of {@code s1} and {@code s2} is exactly equal to
! * the <em>value</em> of {@code s3}.
*
* @param s1 a {@code Spring} object
* @param s2 a {@code Spring} object
! * @return {@code s1+s2}: a spring representing {@code s1} and {@code s2} in series
*
* @see Spring
*/
public static Spring sum(Spring s1, Spring s2) {
return new SumSpring(s1, s2);
*** 621,643 ****
*/
/**
* Returns a spring whose <em>minimum</em>, <em>preferred</em>, <em>maximum</em>
* and <em>value</em> properties are each multiples of the properties of the
! * argument spring, <code>s</code>. Minimum and maximum properties are
! * swapped when <code>factor</code> is negative (in accordance with the
* rules of interval arithmetic).
* <p>
* When factor is, for example, 0.5f the result represents 'the mid-point'
* of its input - an operation that is useful for centering components in
* a container.
*
* @param s the spring to scale
* @param factor amount to scale by.
! * @return a spring whose properties are those of the input spring <code>s</code>
! * multiplied by <code>factor</code>
! * @throws NullPointerException if <code>s</code> is null
* @since 1.5
*/
public static Spring scale(Spring s, float factor) {
checkArg(s);
return new ScaleSpring(s, factor);
--- 621,643 ----
*/
/**
* Returns a spring whose <em>minimum</em>, <em>preferred</em>, <em>maximum</em>
* and <em>value</em> properties are each multiples of the properties of the
! * argument spring, {@code s}. Minimum and maximum properties are
! * swapped when {@code factor} is negative (in accordance with the
* rules of interval arithmetic).
* <p>
* When factor is, for example, 0.5f the result represents 'the mid-point'
* of its input - an operation that is useful for centering components in
* a container.
*
* @param s the spring to scale
* @param factor amount to scale by.
! * @return a spring whose properties are those of the input spring {@code s}
! * multiplied by {@code factor}
! * @throws NullPointerException if {@code s} is null
* @since 1.5
*/
public static Spring scale(Spring s, float factor) {
checkArg(s);
return new ScaleSpring(s, factor);
*** 654,664 ****
* component and track them as they change.
*
* @param c Component used for calculating size
* @return a spring whose properties are defined by the horizontal component
* of the component's size methods.
! * @throws NullPointerException if <code>c</code> is null
* @since 1.5
*/
public static Spring width(Component c) {
checkArg(c);
return new WidthSpring(c);
--- 654,664 ----
* component and track them as they change.
*
* @param c Component used for calculating size
* @return a spring whose properties are defined by the horizontal component
* of the component's size methods.
! * @throws NullPointerException if {@code c} is null
* @since 1.5
*/
public static Spring width(Component c) {
checkArg(c);
return new WidthSpring(c);
*** 675,695 ****
* component and track them as they change.
*
* @param c Component used for calculating size
* @return a spring whose properties are defined by the vertical component
* of the component's size methods.
! * @throws NullPointerException if <code>c</code> is null
* @since 1.5
*/
public static Spring height(Component c) {
checkArg(c);
return new HeightSpring(c);
}
/**
! * If <code>s</code> is null, this throws an NullPointerException.
*/
private static void checkArg(Object s) {
if (s == null) {
throw new NullPointerException("Argument must not be null");
}
--- 675,695 ----
* component and track them as they change.
*
* @param c Component used for calculating size
* @return a spring whose properties are defined by the vertical component
* of the component's size methods.
! * @throws NullPointerException if {@code c} is null
* @since 1.5
*/
public static Spring height(Component c) {
checkArg(c);
return new HeightSpring(c);
}
/**
! * If {@code s} is null, this throws an NullPointerException.
*/
private static void checkArg(Object s) {
if (s == null) {
throw new NullPointerException("Argument must not be null");
}
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