preferences added

res/values/default_values.xml

@@ -12,4 +12,10 @@
 	<string name="p_drag_angle">0;45</string>
 	<string name="p_drag_duration_key">org.solovyev.android.calculator.DragButtonCalibrationActivity_duration</string>
 	<string name="p_drag_duration">40;2500</string>
+
+	<string name="p_calc_result_precision_key">org.solovyev.android.calculator.CalculatorModel_result_precision</string>
+	<string name="p_calc_result_precision">5</string>
+
+	<string name="p_calc_color_display_key">org.solovyev.android.calculator.CalculatorModel_color_display</string>
+	<string name="p_calc_color_display">true</string>
 </resources>

res/xml/preferences.xml

@@ -4,14 +4,16 @@
 				  xmlns:range="http://schemas.android.com/apk/res/org.solovyev.android.calculator">
 	<PreferenceCategory a:title="@string/c_prefs_drag_button_category">
 
-		<org.solovyev.android.view.prefs.SeekBarPreference a:key="duration"
+		<org.solovyev.android.view.prefs.NumberPickerDialogPreference
-														   a:title="Duration of something"
+				a:key="@string/p_calc_result_precision_key"
-														   a:summary="How long something will last"
+				a:title="Precision of result value"
-														   a:dialogMessage="Something duration"
 				a:defaultValue="5"
-														   a:text=" minutes"
+				range:boundaries="0;10"/>
-														   a:max="60"/>
 
+		<android.preference.CheckBoxPreference
+			a:key="@string/p_calc_color_display_key"
+			a:title="Highlight expressions in brackets"
+			a:defaultValue="true"/>
 
 		<org.solovyev.android.view.prefs.FloatRangeSeekBarPreference
 				a:key="@string/p_drag_distance_key"

src/main/java/org/solovyev/android/calculator/CalculatorActivity.java

@@ -20,6 +20,8 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.solovyev.android.view.FontSizeAdjuster;
 import org.solovyev.android.view.widgets.*;
+import org.solovyev.common.BooleanMapper;
+import org.solovyev.common.NumberMapper;
 import org.solovyev.common.utils.Announcer;
 import org.solovyev.common.utils.history.HistoryAction;
 
@@ -104,7 +106,10 @@ public class CalculatorActivity extends Activity implements FontSizeAdjuster, Sh
 
 		registerReceiver(preferencesChangesReceiver, new IntentFilter(DragButtonCalibrationActivity.INTENT_ACTION));
 
-		PreferenceManager.getDefaultSharedPreferences(this).registerOnSharedPreferenceChangeListener(this);
+		final SharedPreferences defaultSharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
+		defaultSharedPreferences.registerOnSharedPreferenceChangeListener(this);
+
+		this.onSharedPreferenceChanged(defaultSharedPreferences, null);
 	}
 
 	@Override
@@ -236,5 +241,12 @@ public class CalculatorActivity extends Activity implements FontSizeAdjuster, Sh
 	@Override
 	public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String s) {
 		dpclRegister.announce().onDragPreferencesChange(DragButtonCalibrationActivity.getPreferences(CalculatorActivity.this));
+
+		final NumberMapper<Integer> integerNumberMapper = new NumberMapper<Integer>(Integer.class);
+		this.calculatorModel.setNumberOfFractionDigits(integerNumberMapper.parseValue(sharedPreferences.getString(this.getString(R.string.p_calc_result_precision_key), this.getString(R.string.p_calc_result_precision))));
+
+		final Boolean colorExpressionsInBracketsDefault = new BooleanMapper().parseValue(this.getString(R.string.p_calc_color_display));
+		assert colorExpressionsInBracketsDefault != null;
+		this.calculatorView.getEditor().setHighlightExpressionInBrackets(sharedPreferences.getBoolean(this.getString(R.string.p_calc_color_display_key), colorExpressionsInBracketsDefault));
 	}
 }

src/main/java/org/solovyev/android/calculator/CalculatorEditText.java

@@ -22,6 +22,7 @@ import org.solovyev.android.calculator.math.MathEntityType;
  */
 public class CalculatorEditText extends EditText {
 
+	private boolean highlightExpressionInBrackets = true;
 
 	public CalculatorEditText(Context context) {
 		super(context);
@@ -42,9 +43,12 @@ public class CalculatorEditText extends EditText {
 
 	public void redraw() {
 		String text = getText().toString();
+
 		int selectionStart = getSelectionStart();
 		int selectionEnd = getSelectionEnd();
 
+		if (highlightExpressionInBrackets) {
+
 			int maxNumberOfOpenGroupSymbols = 0;
 			int numberOfOpenGroupSymbols = 0;
 			for (int i = 0; i < text.length(); i++) {
@@ -69,6 +73,9 @@ public class CalculatorEditText extends EditText {
 			} else {
 				super.setText(text, BufferType.EDITABLE);
 			}
+		} else {
+			super.setText(text, BufferType.EDITABLE);
+		}
 
 		setSelection(selectionStart, selectionEnd);
 	}
@@ -106,10 +113,19 @@ public class CalculatorEditText extends EditText {
 
 		double c = 1;
 
-		int i = ((int)(255 * c)) * numberOfOpenings / (numberOfOpenGroupSymbols + 1);
+		int i = ((int) (255 * c)) * numberOfOpenings / (numberOfOpenGroupSymbols + 1);
 
-		int result = Color.rgb( Color.red(baseColor) - i, Color.green(baseColor) - i, Color.blue(baseColor) - i);
+		int result = Color.rgb(Color.red(baseColor) - i, Color.green(baseColor) - i, Color.blue(baseColor) - i);
 
 		return "#" + Integer.toHexString(result).substring(2);
 	}
+
+	public boolean isHighlightExpressionInBrackets() {
+		return highlightExpressionInBrackets;
+	}
+
+	public void setHighlightExpressionInBrackets(boolean highlightExpressionInBrackets) {
+		this.highlightExpressionInBrackets = highlightExpressionInBrackets;
+		redraw();
+	}
 }

src/main/java/org/solovyev/android/calculator/CalculatorModel.java

@@ -23,7 +23,7 @@ public class CalculatorModel {
 	@NotNull
 	private Interpreter interpreter;
 
-	private int NUMBER_OF_FRACTION_DIGITS = 5;
+	private int numberOfFractionDigits = 5;
 
 	@NotNull
 	public Preprocessor preprocessor = new ToJsclPreprocessor();
@@ -96,7 +96,7 @@ public class CalculatorModel {
 
 	private Double round(@NotNull String result) {
 		final Double dResult = Double.valueOf(result);
-		return MathUtils.round(dResult, NUMBER_OF_FRACTION_DIGITS);
+		return MathUtils.round(dResult, numberOfFractionDigits);
 	}
 
 	public static class ParseException extends SersoException {
@@ -105,4 +105,11 @@ public class CalculatorModel {
 		}
 	}
 
+	public int getNumberOfFractionDigits() {
+		return numberOfFractionDigits;
+	}
+
+	public void setNumberOfFractionDigits(int numberOfFractionDigits) {
+		this.numberOfFractionDigits = numberOfFractionDigits;
+	}
 }

src/main/java/org/solovyev/android/calculator/CalculatorView.java

@@ -285,4 +285,9 @@ public class CalculatorView implements CursorControl, HistoryControl<CalculatorH
 
 		return result;
 	}
+
+	@NotNull
+	public CalculatorEditText getEditor() {
+		return editor;
+	}
 }

src/main/java/org/solovyev/android/calculator/DragButtonCalibrationActivity.java

@@ -19,7 +19,7 @@ import android.view.View;
 import android.widget.ImageView;
 import org.jetbrains.annotations.NotNull;
 import org.solovyev.android.view.widgets.*;
-import org.solovyev.common.FloatIntervalMapper;
+import org.solovyev.common.NumberIntervalMapper;
 import org.solovyev.common.collections.ManyValuedHashMap;
 import org.solovyev.common.collections.ManyValuedMap;
 import org.solovyev.common.utils.*;
@@ -178,7 +178,7 @@ public class DragButtonCalibrationActivity extends Activity {
 	}
 
 	private void setPreferences(@NotNull Map<DragDirection, MathUtils.StatData> statData, @NotNull SharedPreferences.Editor editor, @NotNull PreferenceType preferenceType) {
-		final Mapper<Interval<Float>> mapper = new FloatIntervalMapper();
+		final Mapper<Interval<Float>> mapper = new NumberIntervalMapper<Float>(Float.class);
 		for (Map.Entry<DragDirection, MathUtils.StatData> entry : statData.entrySet()) {
 			final float min = (float) entry.getValue().getMean() - 2 * (float) entry.getValue().getStandardDeviation();
 			final float max = (float) entry.getValue().getMean() + 2 * (float) entry.getValue().getStandardDeviation();
@@ -195,7 +195,7 @@ public class DragButtonCalibrationActivity extends Activity {
 	public static Preferences getPreferences(@NotNull Context context) {
 		final SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
 
-		final Mapper<Interval<Float>> mapper = new FloatIntervalMapper();
+		final Mapper<Interval<Float>> mapper = new NumberIntervalMapper<Float>(Float.class);
 
 		final Preferences result = new Preferences();
 

src/main/java/org/solovyev/android/calculator/EditorHistoryState.java

@@ -22,10 +22,11 @@ public class EditorHistoryState {
 		this.text = text;
 	}
 
-	public void setText(String text) {
+	public void setText(@Nullable String text) {
 		this.text = text;
 	}
 
+	@Nullable
 	public String getText() {
 		return text;
 	}

src/main/java/org/solovyev/android/calculator/ToJsclPreprocessor.java

@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
  * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
  */
 
 package org.solovyev.android.calculator;

src/main/java/org/solovyev/android/calculator/math/Factorial.java

@@ -1,7 +1,12 @@
+/*
+ * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+ * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
+ */
+
 package org.solovyev.android.calculator.math;
 
 import jscl.math.Generic;
-import jscl.math.JSCLInteger;
 import jscl.math.NotIntegrableException;
 import jscl.math.Variable;
 import jscl.math.function.Function;

src/main/java/org/solovyev/android/view/prefs/AbstractDialogPreference.java

@@ -3,6 +3,7 @@ package org.solovyev.android.view.prefs;
 import android.content.Context;
 import android.preference.DialogPreference;
 import android.util.AttributeSet;
+import android.util.Log;
 import android.view.Gravity;
 import android.view.View;
 import android.widget.LinearLayout;
@@ -19,7 +20,10 @@ import org.solovyev.common.utils.Mapper;
 public abstract class AbstractDialogPreference<T> extends DialogPreference {
 
 	@NotNull
-	protected static final String androidns = "http://schemas.android.com/apk/res/android";
+	protected final static String localNameSpace = "http://schemas.android.com/apk/res/org.solovyev.android.calculator";
+
+	@NotNull
+	protected final static String androidns = "http://schemas.android.com/apk/res/android";
 
 	@NotNull
 	protected TextView valueTextView;
@@ -127,21 +131,29 @@ public abstract class AbstractDialogPreference<T> extends DialogPreference {
 	}
 
 	protected void persistValue(@Nullable T value) {
+		Log.d(AbstractDialogPreference.class.getName(), "Trying to persist value: " + value);
+		this.value = value;
+
+		Log.d(AbstractDialogPreference.class.getName(), "android.preference.Preference.callChangeListener()");
 		if (callChangeListener(value)) {
+			Log.d(AbstractDialogPreference.class.getName(), "android.preference.Preference.shouldPersist()");
 			if (shouldPersist()) {
+				Log.d(AbstractDialogPreference.class.getName(), "org.solovyev.android.view.prefs.AbstractDialogPreference.persist()");
 				persist(value);
 			}
 		}
 	}
 
 	private void persist(@Nullable T value) {
+		if (value != null) {
 			final String toBePersistedString = getMapper().formatValue(value);
 			if (toBePersistedString != null) {
-			if ( callChangeListener(value) ) {
+				if ( callChangeListener(toBePersistedString) ) {
 					persistString(toBePersistedString);
 				}
 			}
 		}
+	}
 
 	@NotNull
 	protected abstract Mapper<T> getMapper();

src/main/java/org/solovyev/android/view/prefs/FloatRangeSeekBarPreference.java

@@ -9,7 +9,7 @@ package org.solovyev.android.view.prefs;
 import android.content.Context;
 import android.util.AttributeSet;
 import org.jetbrains.annotations.NotNull;
-import org.solovyev.common.FloatIntervalMapper;
+import org.solovyev.common.NumberIntervalMapper;
 import org.solovyev.common.utils.Interval;
 import org.solovyev.common.utils.Mapper;
 
@@ -27,6 +27,6 @@ public class FloatRangeSeekBarPreference extends RangeSeekBarPreference<Float> {
 	@NotNull
 	@Override
 	protected Mapper<Interval<Float>> getMapper() {
-		return new FloatIntervalMapper() ;
+		return new NumberIntervalMapper<Float>(Float.class);
 	}
 }

src/main/java/org/solovyev/android/view/prefs/IntegerRangeSeekBarPreference.java

@@ -9,7 +9,7 @@ package org.solovyev.android.view.prefs;
 import android.content.Context;
 import android.util.AttributeSet;
 import org.jetbrains.annotations.NotNull;
-import org.solovyev.common.IntegerIntervalMapper;
+import org.solovyev.common.NumberIntervalMapper;
 import org.solovyev.common.utils.*;
 
 /**
@@ -26,7 +26,7 @@ public class IntegerRangeSeekBarPreference extends RangeSeekBarPreference<Intege
 	@NotNull
 	@Override
 	protected Mapper<Interval<Integer>> getMapper() {
-		return new IntegerIntervalMapper();
+		return new NumberIntervalMapper<Integer>(Integer.class);
 	}
 
 }

src/main/java/org/solovyev/android/view/prefs/NumberPickerDialogPreference.java

@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+ * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
+ */
+
+package org.solovyev.android.view.prefs;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.view.Gravity;
+import android.widget.LinearLayout;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.solovyev.android.view.widgets.NumberPicker;
+import org.solovyev.common.GenericIntervalMapper;
+import org.solovyev.common.utils.Interval;
+import org.solovyev.common.utils.Mapper;
+
+/**
+ * User: serso
+ * Date: 9/26/11
+ * Time: 10:31 PM
+ */
+public class NumberPickerDialogPreference extends AbstractDialogPreference<Integer> implements NumberPicker.OnChangedListener {
+
+	@NotNull
+	private NumberPicker numberPicker;
+
+	@NotNull
+	private final Interval<Integer> boundaries;
+
+	public NumberPickerDialogPreference(Context context, AttributeSet attrs) {
+		super(context, attrs, null);
+
+		//noinspection ConstantConditions
+		boundaries = new GenericIntervalMapper<Integer>(getMapper()).parseValue(attrs.getAttributeValue(localNameSpace, "boundaries"));
+
+		createPreferenceView();
+	}
+
+	@NotNull
+	@Override
+	protected LinearLayout onCreateDialogView() {
+		final LinearLayout result = super.onCreateDialogView();
+
+		createPreferenceView();
+		initPreferenceView();
+
+		LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
+		params.gravity = Gravity.CENTER;
+		result.addView(numberPicker, params);
+
+		return result;
+	}
+
+	protected void createPreferenceView() {
+		this.numberPicker = new NumberPicker(context);
+		this.numberPicker.setOnChangeListener(this);
+
+		initPreferenceView();
+	}
+
+	@Override
+	protected void initPreferenceView() {
+		if (value != null) {
+			numberPicker.setRange(boundaries.getLeftBorder(), boundaries.getRightBorder());
+			numberPicker.setCurrent(value);
+		}
+	}
+
+	@NotNull
+	@Override
+	protected Mapper<Integer> getMapper() {
+		return new Mapper<Integer>() {
+			@Override
+			public String formatValue(@Nullable Integer value) throws IllegalArgumentException {
+				return String.valueOf(value);
+			}
+
+			@Override
+			public Integer parseValue(@Nullable String value) throws IllegalArgumentException {
+				return Integer.valueOf(value);
+			}
+		};
+	}
+
+	@Override
+	public void onChanged(NumberPicker picker, int oldVal, int newVal) {
+		persistValue(newVal);
+	}
+}

src/main/java/org/solovyev/android/view/prefs/RangeSeekBarPreference.java

@@ -16,8 +16,6 @@ import org.solovyev.common.utils.NumberInterval;
  */
 public abstract class RangeSeekBarPreference<T extends Number> extends AbstractDialogPreference<Interval<T>> implements AbstractRangeSeekBar.OnRangeSeekBarChangeListener<T> {
 
-	public final static String localNameSpace = "http://schemas.android.com/apk/res/org.solovyev.android.calculator";
-
 	@NotNull
 	private AbstractRangeSeekBar<T> rangeSeekBar;
 

src/main/java/org/solovyev/android/view/prefs/SeekBarPreference.java

@@ -11,7 +11,7 @@ import android.util.AttributeSet;
 import android.widget.LinearLayout;
 import android.widget.SeekBar;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
+import org.solovyev.common.NumberMapper;
 import org.solovyev.common.utils.Mapper;
 
 
@@ -60,17 +60,7 @@ public class SeekBarPreference extends AbstractDialogPreference<Integer> impleme
 	@NotNull
 	@Override
 	protected Mapper<Integer> getMapper() {
-		return new Mapper<Integer>() {
+		return new NumberMapper<Integer>(Integer.class);
-			@Override
-			public String formatValue(@Nullable Integer integer) throws IllegalArgumentException {
-				return integer == null ? null : String.valueOf(integer);
-			}
-
-			@Override
-			public Integer parseValue(@Nullable String s) throws IllegalArgumentException {
-				return s == null ? null : Integer.valueOf(s);
-			}
-		};
 	}
 
 	public void onProgressChanged(SeekBar seek, int value, boolean fromTouch) {

src/main/java/org/solovyev/common/BooleanMapper.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+ * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
+ */
+
+package org.solovyev.common;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.solovyev.common.math.ValueOfFormatter;
+import org.solovyev.common.utils.Formatter;
+import org.solovyev.common.utils.Mapper;
+
+/**
+ * User: serso
+ * Date: 9/26/11
+ * Time: 11:27 PM
+ */
+public class BooleanMapper implements Mapper<Boolean>{
+
+	@NotNull
+	private final Formatter<Boolean> formatter = new ValueOfFormatter<Boolean>();
+
+	@Override
+	public String formatValue(@Nullable Boolean value) throws IllegalArgumentException {
+		return formatter.formatValue(value);
+	}
+
+	@Override
+	public Boolean parseValue(@Nullable String value) throws IllegalArgumentException {
+		return value == null ? null : Boolean.valueOf(value);
+	}
+}

src/main/java/org/solovyev/common/FloatIntervalMapper.java

@@ -1,37 +0,0 @@
-/*
- * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
- * For more information, please, contact se.solovyev@gmail.com
- * or visit http://se.solovyev.org
- */
-
-package org.solovyev.common;
-
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-import org.solovyev.common.math.ValueOfFormatter;
-import org.solovyev.common.utils.Formatter;
-import org.solovyev.common.utils.Parser;
-
-/**
- * User: serso
- * Date: 9/21/11
- * Time: 12:06 AM
- */
-public class FloatIntervalMapper extends AbstractIntervalMapper<Float> {
-	@NotNull
-	@Override
-	protected Formatter<Float> getFormatter() {
-		return new ValueOfFormatter<Float>();
-	}
-
-	@NotNull
-	@Override
-	protected Parser<Float> getParser() {
-		return new Parser<Float>() {
-			@Override
-			public Float parseValue(@Nullable String s) throws IllegalArgumentException {
-				return Float.valueOf(s);
-			}
-		};
-	}
-}

src/main/java/org/solovyev/common/GenericIntervalMapper.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+ * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
+ */
+
+package org.solovyev.common;
+
+import org.jetbrains.annotations.NotNull;
+import org.solovyev.common.utils.Formatter;
+import org.solovyev.common.utils.Mapper;
+import org.solovyev.common.utils.Parser;
+
+/**
+ * User: serso
+ * Date: 9/26/11
+ * Time: 10:45 PM
+ */
+public class GenericIntervalMapper<T> extends AbstractIntervalMapper<T> {
+
+	@NotNull
+	private final Mapper<T> mapper;
+
+	public GenericIntervalMapper(@NotNull Mapper<T> mapper) {
+		this.mapper = mapper;
+	}
+
+	@NotNull
+	@Override
+	protected Formatter<T> getFormatter() {
+		return mapper;
+	}
+
+	@NotNull
+	@Override
+	protected Parser<T> getParser() {
+		return mapper;
+	}
+}

src/main/java/org/solovyev/common/IntegerIntervalMapper.java

@@ -1,35 +0,0 @@
-/*
- * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
- * For more information, please, contact se.solovyev@gmail.com
- * or visit http://se.solovyev.org
- */
-
-package org.solovyev.common;
-
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-import org.solovyev.common.math.ValueOfFormatter;
-import org.solovyev.common.utils.*;
-
-/**
-* User: serso
-* Date: 9/20/11
-* Time: 11:56 PM
-*/
-public class IntegerIntervalMapper extends AbstractIntervalMapper<Integer> {
-
-	@NotNull
-	protected Formatter<Integer> getFormatter() {
-		return new ValueOfFormatter<Integer>();
-	}
-
-	@NotNull
-	protected Parser<Integer> getParser() {
-		return new Parser<Integer>() {
-			@Override
-			public Integer parseValue(@Nullable String s) throws IllegalArgumentException {
-				return Integer.valueOf(s);
-			}
-		};
-	}
-}

src/main/java/org/solovyev/common/NumberIntervalMapper.java

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+ * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
+ */
+
+package org.solovyev.common;
+
+import org.jetbrains.annotations.NotNull;
+
+/**
+* User: serso
+* Date: 9/20/11
+* Time: 11:56 PM
+*/
+public class NumberIntervalMapper<T extends Number> extends GenericIntervalMapper<T> {
+
+	public NumberIntervalMapper(@NotNull Class<T> clazz) {
+		super(new NumberMapper<T>(clazz));
+	}
+}

src/main/java/org/solovyev/common/NumberMapper.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+ * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
+ */
+
+package org.solovyev.common;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.solovyev.common.math.ValueOfFormatter;
+import org.solovyev.common.utils.Formatter;
+import org.solovyev.common.utils.Mapper;
+import org.solovyev.common.utils.Parser;
+
+/**
+ * User: serso
+ * Date: 9/26/11
+ * Time: 11:10 PM
+ */
+public class NumberMapper<T extends Number> implements Mapper<T>{
+
+	@NotNull
+	private final Formatter<T> formatter = new ValueOfFormatter<T>();
+
+	@NotNull
+	private final Parser<T> parser;
+
+	public NumberMapper(@NotNull Class<T> clazz) {
+		this.parser = new NumberParser<T>(clazz);
+	}
+
+	@Override
+	public String formatValue(@Nullable T value) throws IllegalArgumentException {
+		return formatter.formatValue(value);
+	}
+
+	@Override
+	public T parseValue(@Nullable String value) throws IllegalArgumentException {
+		return this.parser.parseValue(value);
+	}
+}

src/main/java/org/solovyev/common/NumberParser.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+ * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
+ */
+
+package org.solovyev.common;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.solovyev.common.utils.Parser;
+
+/**
+ * User: serso
+ * Date: 9/26/11
+ * Time: 11:07 PM
+ */
+public class NumberParser<T extends Number> implements Parser<T> {
+
+	@NotNull
+	private final Class<T> clazz;
+
+	public NumberParser(@NotNull Class<T> clazz) {
+		this.clazz = clazz;
+	}
+
+	@Override
+	public T parseValue(@Nullable String value) throws IllegalArgumentException {
+		T result;
+
+		if (value != null) {
+			if (this.clazz.equals(Integer.class)) {
+				result = (T) Integer.valueOf(value);
+			} else if (this.clazz.equals(Float.class)) {
+				result = (T) Float.valueOf(value);
+			} else {
+				throw new UnsupportedOperationException(this.clazz + " is not supported!");
+			}
+		} else {
+			result = null;
+		}
+
+		return result;
+	}
+}

src/main/java/org/solovyev/common/math/ValueOfFormatter.java

@@ -16,8 +16,19 @@ import org.solovyev.common.utils.Formatter;
  */
 public class ValueOfFormatter<T> implements Formatter<T>{
 
+	private final boolean processNulls;
+
+	public ValueOfFormatter() {
+		this(false);
+	}
+
+	public ValueOfFormatter(boolean processNulls) {
+		this.processNulls = processNulls;
+	}
+
+
 	@Override
 	public String formatValue(@Nullable T t) throws IllegalArgumentException {
-		return String.valueOf(t);
+		return t == null ? (processNulls ? String.valueOf(t) : null) : String.valueOf(t);
 	}
 }

src/test/java/org/solovyev/android/calculator/CalculatorModelTest.java

@@ -5,10 +5,6 @@
 
 package org.solovyev.android.calculator;
 
-import de.congrace.exp4j.Calculable;
-import de.congrace.exp4j.ExpressionBuilder;
-import de.congrace.exp4j.UnknownFunctionException;
-import de.congrace.exp4j.UnparsableExpressionException;
 import org.junit.Assert;
 import org.junit.Test;
 

src/test/java/org/solovyev/android/calculator/ToJsclPreprocessorTest.java

@@ -1,3 +1,9 @@
+/*
+ * Copyright (c) 2009-2011. Created by serso aka se.solovyev.
+ * For more information, please, contact se.solovyev@gmail.com
+ * or visit http://se.solovyev.org
+ */
+
 package org.solovyev.android.calculator;
 
 import org.junit.Assert;

src/test/java/org/solovyev/common/FloatIntervalMapperTest.java

@@ -2,7 +2,9 @@ package org.solovyev.common;
 
 import junit.framework.Assert;
 import org.junit.Test;
+import org.solovyev.common.utils.Interval;
 import org.solovyev.common.utils.IntervalImpl;
+import org.solovyev.common.utils.Mapper;
 
 /**
  * User: serso
@@ -13,7 +15,7 @@ public class FloatIntervalMapperTest {
 
 	@Test
 	public void testParse() throws Exception {
-		final FloatIntervalMapper mapper = new FloatIntervalMapper();
+		final Mapper<Interval<Float>> mapper = new NumberIntervalMapper<Float>(Float.class);
 
 		Assert.assertEquals(new IntervalImpl<Float>(1.2f, 12.2f), mapper.parseValue("1.2;12.2"));
 		Assert.assertEquals(new IntervalImpl<Float>(0f, 0f), mapper.parseValue("0;0"));