/*
This file belongs to the Servoy development and deployment environment, Copyright (C) 1997-2010 Servoy BV
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Affero General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at your option) any
later version.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License along
with this program; if not, see http://www.gnu.org/licenses or write to the Free
Software Foundation,Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
*/
package com.servoy.j2db.util.gui;
import java.awt.Component;
import javax.swing.SpringLayout;
/**
* For the replace of SpringLayout with FixedSpringLayout we have to replace this class as well
*/
public abstract class Spring {
/**
* 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
* @see #sum
* @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);
private double range(boolean contract) {
return contract ? (getPreferredValue() - getMinimumValue()) :
(getMaximumValue() - getPreferredValue());
}
/*pp*/ double getStrain() {
double delta = (getValue() - getPreferredValue());
return delta/range(getValue() < getPreferredValue());
}
/*pp*/ void setStrain(double strain) {
setValue(getPreferredValue() + (int)(strain * range(strain < 0)));
}
/*pp*/ boolean isCyclic(FixedSpringLayout l) {
return false;
}
public static abstract class AbstractSpring extends Spring {
protected int size = UNSET;
public int getValue() {
return size != UNSET ? size : getPreferredValue();
}
public void setValue(int size) {
if (size == UNSET) {
clear();
return;
}
this.size = size;
}
protected void clear() {
size = UNSET;
}
}
public static class StaticSpring extends AbstractSpring {
protected int min;
protected int pref;
protected int max;
public StaticSpring() {}
public StaticSpring(int pref) {
this(pref, pref, pref);
}
public StaticSpring(int min, int pref, int max) {
this.min = min;
this.pref = pref;
this.max = max;
this.size = pref;
}
public String toString() {
return "StaticSpring [" + min + ", " + pref + ", " + max + "]";
}
public int getMinimumValue() {
return min;
}
public int getPreferredValue() {
return pref;
}
public int getMaximumValue() {
return max;
}
}
private static class NegativeSpring extends Spring {
private Spring s;
public NegativeSpring(Spring s) {
this.s = s;
}
// Note the use of max value rather than minimum value here.
// See the opening preamble on arithmetic with springs.
public int getMinimumValue() {
return -s.getMaximumValue();
}
public int getPreferredValue() {
return -s.getPreferredValue();
}
public int getMaximumValue() {
return -s.getMinimumValue();
}
public int getValue() {
return -s.getValue();
}
public void setValue(int size) {
// No need to check for UNSET as
// Integer.MIN_VALUE == -Integer.MIN_VALUE.
s.setValue(-size);
}
/*pp*/ boolean isCyclic(FixedSpringLayout l) {
return s.isCyclic(l);
}
}
private static class ScaleSpring extends Spring {
private Spring s;
private float factor;
private ScaleSpring(Spring s, float factor) {
this.s = s;
this.factor = factor;
}
public int getMinimumValue() {
return Math.round((factor < 0 ? s.getMaximumValue() : s.getMinimumValue()) * factor);
}
public int getPreferredValue() {
return Math.round(s.getPreferredValue() * factor);
}
public int getMaximumValue() {
return Math.round((factor < 0 ? s.getMinimumValue() : s.getMaximumValue()) * factor);
}
public int getValue() {
return Math.round(s.getValue() * factor);
}
public void setValue(int value) {
if (value == UNSET) {
s.setValue(UNSET);
} else {
s.setValue(Math.round(value / factor));
}
}
/*pp*/ boolean isCyclic(FixedSpringLayout l) {
return s.isCyclic(l);
}
}
/*pp*/ static class WidthSpring extends AbstractSpring {
/*pp*/ Component c;
public WidthSpring(Component c) {
this.c = c;
}
public int getMinimumValue() {
return c.getMinimumSize().width;
}
public int getPreferredValue() {
return c.getPreferredSize().width;
}
public int getMaximumValue() {
// We will be doing arithmetic with the results of this call,
// so if a returned value is Integer.MAX_VALUE we will get
// arithmetic overflow. Truncate such values.
return Math.min(Short.MAX_VALUE, c.getMaximumSize().width);
}
}
public static class HeightSpring extends AbstractSpring {
/*pp*/ Component c;
public HeightSpring(Component c) {
this.c = c;
}
public int getMinimumValue() {
return c.getMinimumSize().height;
}
public int getPreferredValue() {
return c.getPreferredSize().height;
}
public int getMaximumValue() {
return Math.min(Short.MAX_VALUE, c.getMaximumSize().height);
}
}
// Use the instance variables of the StaticSpring superclass to
// cache values that have already been calculated.
/*pp*/ static abstract class CompoundSpring extends StaticSpring {
protected Spring s1;
protected Spring s2;
public CompoundSpring(Spring s1, Spring s2) {
clear();
this.s1 = s1;
this.s2 = s2;
}
public String toString() {
return "CompoundSpring of " + s1 + " and " + s2;
}
protected void clear() {
min = pref = max = size = UNSET;
}
public void setValue(int size) {
if (size == UNSET) {
if (this.size != UNSET) {
super.setValue(size);
s1.setValue(UNSET);
s2.setValue(UNSET);
return;
}
}
super.setValue(size);
}
protected abstract int op(int x, int y);
public int getMinimumValue() {
if (min == UNSET) {
min = op(s1.getMinimumValue(), s2.getMinimumValue());
}
return min;
}
public int getPreferredValue() {
if (pref == UNSET) {
pref = op(s1.getPreferredValue(), s2.getPreferredValue());
}
return pref;
}
public int getMaximumValue() {
if (max == UNSET) {
max = op(s1.getMaximumValue(), s2.getMaximumValue());
}
return max;
}
public int getValue() {
if (size == UNSET) {
size = op(s1.getValue(), s2.getValue());
}
return size;
}
/*pp*/ boolean isCyclic(FixedSpringLayout l) {
return l.isCyclic(s1) || l.isCyclic(s2);
}
};
private static class SumSpring extends CompoundSpring {
public SumSpring(Spring s1, Spring s2) {
super(s1, s2);
}
protected int op(int x, int y) {
return x + y;
}
public void setValue(int size) {
super.setValue(size);
if (size == UNSET) {
return;
}
s1.setStrain(this.getStrain());
s2.setValue(size - s1.getValue());
}
}
private static class MaxSpring extends CompoundSpring {
public MaxSpring(Spring s1, Spring s2) {
super(s1, s2);
}
protected int op(int x, int y) {
return Math.max(x, y);
}
public void setValue(int size) {
super.setValue(size);
if (size == UNSET) {
return;
}
// Pending should also check max bounds here.
if (s1.getPreferredValue() < s2.getPreferredValue()) {
s1.setValue(Math.min(size, s1.getPreferredValue()));
s2.setValue(size);
}
else {
s1.setValue(size);
s2.setValue(Math.min(size, s2.getPreferredValue()));
}
}
}
/**
* 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);
}
/**
* Returns <code>-s</code>: a spring running in the opposite direction to <code>s</code>.
*
* @return <code>-s</code>: a spring running in the opposite direction to <code>s</code>
*
* @see Spring
*/
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
* ------------
* pref - min
* </pre>
* and the strain of a spring in tension is:
* <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>.
*
* @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);
}
/**
* Returns <code>max(s1, s2)</code>: a spring whose value is always greater than (or equal to)
* the values of both <code>s1</code> and <code>s2</code>.
*
* @return <code>max(s1, s2)</code>: a spring whose value is always greater than (or equal to)
* the values of both <code>s1</code> and <code>s2</code>
* @see Spring
*/
public static Spring max(Spring s1, Spring s2) {
return new MaxSpring(s1, s2);
}
// Remove these, they're not used often and can be created using minus -
// as per these implementations.
/*pp*/ static Spring difference(Spring s1, Spring s2) {
return sum(s1, minus(s2));
}
/*
public static Spring min(Spring s1, Spring s2) {
return minus(max(minus(s1), minus(s2)));
}
*/
/**
* 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);
}
/**
* Returns a spring whose <em>minimum</em>, <em>preferred</em>, <em>maximum</em>
* and <em>value</em> properties are defined by the widths of the <em>minimumSize</em>,
* <em>preferredSize</em>, <em>maximumSize</em> and <em>size</em> properties
* of the supplied component. The returned spring is a 'wrapper' implementation
* whose methods call the appropriate size methods of the supplied component.
* The minimum, preferred, maximum and value properties of the returned spring
* therefore report the current state of the appropriate properties in the
* 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);
}
/**
* Returns a spring whose <em>minimum</em>, <em>preferred</em>, <em>maximum</em>
* and <em>value</em> properties are defined by the heights of the <em>minimumSize</em>,
* <em>preferredSize</em>, <em>maximumSize</em> and <em>size</em> properties
* of the supplied component. The returned spring is a 'wrapper' implementation
* whose methods call the appropriate size methods of the supplied component.
* The minimum, preferred, maximum and value properties of the returned spring
* therefore report the current state of the appropriate properties in the
* 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");
}
}
}