From: Artur Signell <artur@vaadin.com>
Date: Fri, 25 Nov 2011 15:48:47 +0000 (+0200)
Subject: First take on Converters
X-Git-Tag: 7.0.0.alpha1~230^2~18
X-Git-Url: https://source.dussan.org/?a=commitdiff_plain;h=3053cf8f876e4bac0bfce4e90ad7301ffc3f27b8;p=vaadin-framework.git

First take on Converters
---

diff --git a/src/com/vaadin/data/util/converter/BooleanToStringConverter.java b/src/com/vaadin/data/util/converter/BooleanToStringConverter.java
new file mode 100644
index 0000000000..cdb7d9e9bc
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/BooleanToStringConverter.java
@@ -0,0 +1,32 @@
+package com.vaadin.data.util.converter;
+
+import java.util.Locale;
+
+public class BooleanToStringConverter implements Converter<Boolean, String> {
+
+    public Boolean convertFromTargetToSource(String value, Locale locale) {
+        try {
+            return Boolean.valueOf(value);
+        } catch (Exception e) {
+            throw new ConversionException("Cannot convert " + value
+                    + " to Boolean");
+        }
+    }
+
+    public String convertFromSourceToTarget(Boolean value, Locale locale) {
+        if (value == null) {
+            return "";
+        }
+
+        return value.toString();
+    }
+
+    public Class<Boolean> getSourceType() {
+        return Boolean.class;
+    }
+
+    public Class<String> getTargetType() {
+        return String.class;
+    }
+
+}
diff --git a/src/com/vaadin/data/util/converter/Converter.java b/src/com/vaadin/data/util/converter/Converter.java
new file mode 100644
index 0000000000..fc1db77703
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/Converter.java
@@ -0,0 +1,72 @@
+package com.vaadin.data.util.converter;
+
+import java.io.Serializable;
+import java.util.Locale;
+
+public interface Converter<SOURCE, TARGET> extends Serializable {
+
+    public SOURCE convertFromTargetToSource(TARGET value, Locale locale)
+            throws ConversionException;
+
+    public TARGET convertFromSourceToTarget(SOURCE value, Locale locale)
+            throws ConversionException;
+
+    public Class<SOURCE> getSourceType();
+
+    public Class<TARGET> getTargetType();
+
+    /**
+     * An exception that signals that the value passed to #convert or
+     * Converter.convertFromTargetToSource could not be converted.
+     * 
+     * @author Vaadin Ltd
+     * @version
+     * @VERSION@
+     * @since 7.0
+     */
+    public class ConversionException extends RuntimeException {
+
+        /**
+         * Constructs a new <code>ConversionException</code> without a detail
+         * message.
+         */
+        public ConversionException() {
+        }
+
+        /**
+         * Constructs a new <code>ConversionException</code> with the specified
+         * detail message.
+         * 
+         * @param msg
+         *            the detail message
+         */
+        public ConversionException(String msg) {
+            super(msg);
+        }
+
+        /**
+         * Constructs a new {@code ConversionException} with the specified
+         * cause.
+         * 
+         * @param cause
+         *            The cause of the the exception
+         */
+        public ConversionException(Throwable cause) {
+            super(cause);
+        }
+
+        /**
+         * Constructs a new <code>ConversionException</code> with the specified
+         * detail message and cause.
+         * 
+         * @param message
+         *            the detail message
+         * @param cause
+         *            The cause of the the exception
+         */
+        public ConversionException(String message, Throwable cause) {
+            super(message, cause);
+        }
+    }
+
+}
diff --git a/src/com/vaadin/data/util/converter/ConverterFactory.java b/src/com/vaadin/data/util/converter/ConverterFactory.java
new file mode 100644
index 0000000000..e36e8c0578
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/ConverterFactory.java
@@ -0,0 +1,7 @@
+package com.vaadin.data.util.converter;
+
+public interface ConverterFactory {
+    <SOURCE, TARGET> Converter<SOURCE, TARGET> createConverter(
+            Class<SOURCE> sourceType, Class<TARGET> targetType);
+
+}
diff --git a/src/com/vaadin/data/util/converter/DateToStringConverter.java b/src/com/vaadin/data/util/converter/DateToStringConverter.java
new file mode 100644
index 0000000000..b46fa75c75
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/DateToStringConverter.java
@@ -0,0 +1,50 @@
+package com.vaadin.data.util.converter;
+
+import java.text.DateFormat;
+import java.text.ParsePosition;
+import java.util.Date;
+import java.util.Locale;
+
+public class DateToStringConverter implements Converter<Date, String> {
+
+    public Date convertFromTargetToSource(String value, Locale locale)
+            throws com.vaadin.data.util.converter.Converter.ConversionException {
+        if (value == null) {
+            return null;
+        }
+
+        ParsePosition parsePosition = new ParsePosition(0);
+        Date parsedValue = getFormat(locale).parse(value, parsePosition);
+        if (parsePosition.getIndex() != value.length()) {
+            throw new ConversionException("Could not convert '" + value
+                    + "' to " + getTargetType().getName());
+        }
+
+        return parsedValue;
+    }
+
+    public String convertFromSourceToTarget(Date value, Locale locale)
+            throws com.vaadin.data.util.converter.Converter.ConversionException {
+        if (value == null) {
+            return null;
+        }
+
+        return getFormat(locale).format(value);
+    }
+
+    protected DateFormat getFormat(Locale locale) {
+        DateFormat f = DateFormat.getDateTimeInstance(DateFormat.MEDIUM,
+                DateFormat.MEDIUM, locale);
+        f.setLenient(false);
+        return f;
+    }
+
+    public Class<Date> getSourceType() {
+        return Date.class;
+    }
+
+    public Class<String> getTargetType() {
+        return String.class;
+    }
+
+}
diff --git a/src/com/vaadin/data/util/converter/DefaultConverterFactory.java b/src/com/vaadin/data/util/converter/DefaultConverterFactory.java
new file mode 100644
index 0000000000..8ddd35a2d8
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/DefaultConverterFactory.java
@@ -0,0 +1,77 @@
+package com.vaadin.data.util.converter;
+
+import java.util.Date;
+
+public class DefaultConverterFactory implements ConverterFactory {
+
+    public <SOURCE, TARGET> Converter<SOURCE, TARGET> createConverter(
+            Class<SOURCE> sourceType, Class<TARGET> targetType) {
+        Converter<SOURCE, TARGET> converter = findConverter(sourceType,
+                targetType);
+        if (converter != null) {
+            System.out.println(getClass().getName() + " created a "
+                    + converter.getClass());
+            return converter;
+        }
+
+        // Try to find a reverse converter
+        Converter<TARGET, SOURCE> reverseConverter = findConverter(targetType,
+                sourceType);
+        if (reverseConverter != null) {
+            System.out.println(getClass().getName() + " created a reverse "
+                    + reverseConverter.getClass());
+            return new ReverseConverter<SOURCE, TARGET>(reverseConverter);
+        }
+
+        System.out.println(getClass().getName()
+                + " could not find a converter for " + sourceType.getName()
+                + " to " + targetType.getName() + " conversion");
+        return null;
+
+    }
+
+    protected <SOURCE, TARGET> Converter<SOURCE, TARGET> findConverter(
+            Class<SOURCE> sourceType, Class<TARGET> targetType) {
+        if (targetType == String.class) {
+            // TextField converters and more
+            Converter<SOURCE, TARGET> converter = (Converter<SOURCE, TARGET>) createStringConverter(sourceType);
+            if (converter != null) {
+                return converter;
+            }
+        } else if (targetType == Date.class) {
+            // DateField converters and more
+            Converter<SOURCE, TARGET> converter = (Converter<SOURCE, TARGET>) createDateConverter(sourceType);
+            if (converter != null) {
+                return converter;
+            }
+        }
+
+        return null;
+
+    }
+
+    protected Converter<?, Date> createDateConverter(Class<?> sourceType) {
+        if (Long.class.isAssignableFrom(sourceType)) {
+            return new LongToDateConverter();
+        } else {
+            return null;
+        }
+    }
+
+    protected Converter<?, String> createStringConverter(Class<?> sourceType) {
+        if (Double.class.isAssignableFrom(sourceType)) {
+            return new DoubleToStringConverter();
+        } else if (Integer.class.isAssignableFrom(sourceType)) {
+            return new IntegerToStringConverter();
+        } else if (Boolean.class.isAssignableFrom(sourceType)) {
+            return new BooleanToStringConverter();
+        } else if (Number.class.isAssignableFrom(sourceType)) {
+            return new NumberToStringConverter();
+        } else if (Date.class.isAssignableFrom(sourceType)) {
+            return new DateToStringConverter();
+        } else {
+            return null;
+        }
+    }
+
+}
diff --git a/src/com/vaadin/data/util/converter/DoubleToStringConverter.java b/src/com/vaadin/data/util/converter/DoubleToStringConverter.java
new file mode 100644
index 0000000000..299ed79bcb
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/DoubleToStringConverter.java
@@ -0,0 +1,38 @@
+package com.vaadin.data.util.converter;
+
+import java.text.NumberFormat;
+import java.text.ParsePosition;
+import java.util.Locale;
+
+public class DoubleToStringConverter implements Converter<Double, String> {
+
+    protected NumberFormat getFormatter(Locale locale) {
+        return NumberFormat.getNumberInstance(locale);
+    }
+
+    public Double convertFromTargetToSource(String value, Locale locale) {
+        ParsePosition parsePosition = new ParsePosition(0);
+        Number parsedValue = getFormatter(locale).parse(value, parsePosition);
+        if (parsePosition.getIndex() != value.length()) {
+            throw new ConversionException("Could not convert '" + value
+                    + "' to " + getTargetType().getName());
+        }
+        return parsedValue.doubleValue();
+    }
+
+    public String convertFromSourceToTarget(Double value, Locale locale) {
+        if (value == null) {
+            return null;
+        }
+
+        return getFormatter(locale).format(value);
+    }
+
+    public Class<Double> getSourceType() {
+        return Double.class;
+    }
+
+    public Class<String> getTargetType() {
+        return String.class;
+    }
+}
diff --git a/src/com/vaadin/data/util/converter/FieldValueConverterFactory.java b/src/com/vaadin/data/util/converter/FieldValueConverterFactory.java
new file mode 100644
index 0000000000..1dc6f42b2e
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/FieldValueConverterFactory.java
@@ -0,0 +1,14 @@
+package com.vaadin.data.util.converter;
+//package com.vaadin.data;
+//
+//import java.io.Serializable;
+//
+//import com.vaadin.ui.Field;
+//
+//public interface FieldValueConverterFactory extends Serializable {
+//
+//    <SOURCE, TARGET> Converter<SOURCE, TARGET> createConverter(
+//            Field<SOURCE> field, Item item, Object propertyId,
+//            Class<TARGET> targetType);
+//
+// }
diff --git a/src/com/vaadin/data/util/converter/IntegerToStringConverter.java b/src/com/vaadin/data/util/converter/IntegerToStringConverter.java
new file mode 100644
index 0000000000..c6d48d55a8
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/IntegerToStringConverter.java
@@ -0,0 +1,57 @@
+package com.vaadin.data.util.converter;
+
+import java.text.NumberFormat;
+import java.text.ParsePosition;
+import java.util.Locale;
+
+public class IntegerToStringConverter implements Converter<Integer, String> {
+
+    protected NumberFormat getFormatter(Locale locale) {
+        if (locale == null) {
+            return NumberFormat.getIntegerInstance();
+        } else {
+            return NumberFormat.getIntegerInstance(locale);
+        }
+    }
+
+    public Integer convertFromTargetToSource(String value, Locale locale) {
+        if (value == null) {
+            return null;
+        }
+
+        // Remove extra spaces
+        value = value.trim();
+
+        // Parse and detect errors. If the full string was not used, it is
+        // an error.
+        ParsePosition parsePosition = new ParsePosition(0);
+        Number parsedValue = getFormatter(locale).parse(value, parsePosition);
+        if (parsePosition.getIndex() != value.length()) {
+            throw new ConversionException("Could not convert '" + value
+                    + "' to " + getTargetType().getName());
+        }
+
+        if (parsedValue == null) {
+            // Convert "" to null
+            return null;
+        }
+        return parsedValue.intValue();
+    }
+
+    public String convertFromSourceToTarget(Integer value, Locale locale) {
+        if (value == null) {
+            return null;
+        }
+
+        return getFormatter(locale).format(value);
+    }
+
+    public Class<Integer> getSourceType() {
+        return Integer.class;
+    }
+
+    public Class<String> getTargetType() {
+        return String.class;
+    }
+
+}
diff --git a/src/com/vaadin/data/util/converter/LongToDateConverter.java b/src/com/vaadin/data/util/converter/LongToDateConverter.java
new file mode 100644
index 0000000000..666c532ae5
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/LongToDateConverter.java
@@ -0,0 +1,32 @@
+package com.vaadin.data.util.converter;
+
+import java.util.Date;
+import java.util.Locale;
+
+public class LongToDateConverter implements Converter<Long, Date> {
+
+    public Long convertFromTargetToSource(Date value, Locale locale) {
+        if (value == null) {
+            return null;
+        }
+
+        return value.getTime();
+    }
+
+    public Date convertFromSourceToTarget(Long value, Locale locale) {
+        if (value == null) {
+            return null;
+        }
+
+        return new Date(value);
+    }
+
+    public Class<Long> getSourceType() {
+        return Long.class;
+    }
+
+    public Class<Date> getTargetType() {
+        return Date.class;
+    }
+
+}
diff --git a/src/com/vaadin/data/util/converter/NumberToStringConverter.java b/src/com/vaadin/data/util/converter/NumberToStringConverter.java
new file mode 100644
index 0000000000..07c6af523d
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/NumberToStringConverter.java
@@ -0,0 +1,57 @@
+package com.vaadin.data.util.converter;
+
+import java.text.NumberFormat;
+import java.text.ParsePosition;
+import java.util.Locale;
+
+public class NumberToStringConverter implements Converter<Number, String> {
+
+    protected NumberFormat getFormatter(Locale locale) {
+        if (locale == null) {
+            return NumberFormat.getNumberInstance();
+        } else {
+            return NumberFormat.getNumberInstance(locale);
+        }
+    }
+
+    public Number convertFromTargetToSource(String value, Locale locale) {
+        if (value == null) {
+            return null;
+        }
+
+        // Remove extra spaces
+        value = value.trim();
+
+        // Parse and detect errors. If the full string was not used, it is
+        // an error.
+        ParsePosition parsePosition = new ParsePosition(0);
+        Number parsedValue = getFormatter(locale).parse(value, parsePosition);
+        if (parsePosition.getIndex() != value.length()) {
+            throw new ConversionException("Could not convert '" + value
+                    + "' to " + getTargetType().getName());
+        }
+
+        if (parsedValue == null) {
+            // Convert "" to null
+            return null;
+        }
+        return parsedValue;
+    }
+
+    public String convertFromSourceToTarget(Number value, Locale locale) {
+        if (value == null) {
+            return null;
+        }
+
+        return getFormatter(locale).format(value);
+    }
+
+    public Class<Number> getSourceType() {
+        return Number.class;
+    }
+
+    public Class<String> getTargetType() {
+        return String.class;
+    }
+
+}
diff --git a/src/com/vaadin/data/util/converter/ReverseConverter.java b/src/com/vaadin/data/util/converter/ReverseConverter.java
new file mode 100644
index 0000000000..590927a769
--- /dev/null
+++ b/src/com/vaadin/data/util/converter/ReverseConverter.java
@@ -0,0 +1,32 @@
+package com.vaadin.data.util.converter;
+
+import java.util.Locale;
+
+public class ReverseConverter<SOURCE, TARGET> implements
+        Converter<SOURCE, TARGET> {
+
+    private Converter<TARGET, SOURCE> realConverter;
+
+    public ReverseConverter(Converter<TARGET, SOURCE> realConverter) {
+        this.realConverter = realConverter;
+    }
+
+    public SOURCE convertFromTargetToSource(TARGET value, Locale locale)
+            throws com.vaadin.data.util.converter.Converter.ConversionException {
+        return realConverter.convertFromSourceToTarget(value, locale);
+    }
+
+    public TARGET convertFromSourceToTarget(SOURCE value, Locale locale)
+            throws com.vaadin.data.util.converter.Converter.ConversionException {
+        return realConverter.convertFromTargetToSource(value, locale);
+    }
+
+    public Class<SOURCE> getSourceType() {
+        return realConverter.getTargetType();
+    }
+
+    public Class<TARGET> getTargetType() {
+        return realConverter.getSourceType();
+    }
+
+}