Simplify our DecimalFormat.

Both the is-a and has-a hierarchies for our DecimalFormat implementation were
over-complicated. This patch starts to address that, and makes cloning twice
as fast (50us versus 100us), but not as fast as I'd like (<10us), and without
making much of a dent in the time it takes to create a new NumberFormat (550us
versus 600us).

The speed of cloning is important because Formatter has a hack that uses it,
and I want to change NumberFormat so that it always hands out clones... at
least until I have time to make "new NumberFormat" acceptably fast.

Also fixes DecimalFormat.applyLocalizedPattern (which used to behave as if
you'd called applyPattern).

3 files changed, 132 insertions, 380 deletions

diff --git a/icu/src/main/java/com/ibm/icu4jni/text/DecimalFormat.java b/icu/src/main/java/com/ibm/icu4jni/text/DecimalFormat.java
index 4b296d5..d995dc6 100644
--- a/icu/src/main/java/com/ibm/icu4jni/text/DecimalFormat.java
+++ b/icu/src/main/java/com/ibm/icu4jni/text/DecimalFormat.java
@@ -18,11 +18,13 @@ package com.ibm.icu4jni.text;
 
 import com.ibm.icu4jni.text.NativeDecimalFormat.UNumberFormatAttribute;
 import com.ibm.icu4jni.text.NativeDecimalFormat.UNumberFormatTextAttribute;
+import com.ibm.icu4jni.util.LocaleData;
 
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.text.AttributedCharacterIterator;
 import java.text.AttributedString;
+import java.text.DecimalFormatSymbols;
 import java.text.FieldPosition;
 import java.text.Format;
 import java.text.NumberFormat;
@@ -30,19 +32,32 @@ import java.text.ParsePosition;
 import java.util.Currency;
 import java.util.Locale;
 
-public class DecimalFormat extends NumberFormat {
-
-    private int addr;
-
-    private DecimalFormatSymbols symbols;
-
-    // fix to be icu4j conform (harmony wants this field to exist)
-    // for serialization of java.text.DecimalFormat
-    @SuppressWarnings("unused")
-    private boolean useExponentialNotation = false;
-    @SuppressWarnings("unused")
-    private byte minExponentDigits = 0;
-
+public class DecimalFormat {
+    // Constants corresponding to the native type UNumberFormatSymbol, for use with getSymbol/setSymbol.
+    private static final int UNUM_DECIMAL_SEPARATOR_SYMBOL = 0;
+    private static final int UNUM_GROUPING_SEPARATOR_SYMBOL = 1;
+    private static final int UNUM_PATTERN_SEPARATOR_SYMBOL = 2;
+    private static final int UNUM_PERCENT_SYMBOL = 3;
+    private static final int UNUM_ZERO_DIGIT_SYMBOL = 4;
+    private static final int UNUM_DIGIT_SYMBOL = 5;
+    private static final int UNUM_MINUS_SIGN_SYMBOL = 6;
+    private static final int UNUM_PLUS_SIGN_SYMBOL = 7;
+    private static final int UNUM_CURRENCY_SYMBOL = 8;
+    private static final int UNUM_INTL_CURRENCY_SYMBOL = 9;
+    private static final int UNUM_MONETARY_SEPARATOR_SYMBOL = 10;
+    private static final int UNUM_EXPONENTIAL_SYMBOL = 11;
+    private static final int UNUM_PERMILL_SYMBOL = 12;
+    private static final int UNUM_PAD_ESCAPE_SYMBOL = 13;
+    private static final int UNUM_INFINITY_SYMBOL = 14;
+    private static final int UNUM_NAN_SYMBOL = 15;
+    private static final int UNUM_SIGNIFICANT_DIGIT_SYMBOL = 16;
+    private static final int UNUM_MONETARY_GROUPING_SEPARATOR_SYMBOL = 17;
+    private static final int UNUM_FORMAT_SYMBOL_COUNT = 18;
+
+    // The address of the ICU DecimalFormat* on the native heap.
+    private final int addr;
+
+    // TODO: store all these in java.text.DecimalFormat instead!
     private boolean negPrefNull;
     private boolean negSuffNull;
     private boolean posPrefNull;
@@ -50,37 +65,52 @@ public class DecimalFormat extends NumberFormat {
 
     /**
      * Cache the BigDecimal form of the multiplier. This is null until we've
-     * formatted a BigDecimal (with a multipler that is not 1), or the user has
+     * formatted a BigDecimal (with a multiplier that is not 1), or the user has
      * explicitly called {@link #setMultiplier(int)} with any multiplier.
      */
     private transient BigDecimal multiplierBigDecimal = null;
 
-    public DecimalFormat(String pattern, DecimalFormatSymbols icuSymbols) {
-        this.addr = icuSymbols.getAddr();
-        this.symbols = icuSymbols;
-        applyPattern(pattern);
+    public DecimalFormat(String pattern, Locale locale, DecimalFormatSymbols symbols) {
+        this.addr = NativeDecimalFormat.openDecimalFormat(locale.toString(), pattern);
+        setDecimalFormatSymbols(symbols);
     }
 
+    // Used to implement clone.
+    private DecimalFormat(DecimalFormat other) {
+        this.addr = NativeDecimalFormat.cloneDecimalFormatImpl(other.addr);
+        this.negPrefNull = other.negPrefNull;
+        this.negSuffNull = other.negSuffNull;
+        this.posPrefNull = other.posPrefNull;
+        this.posSuffNull = other.posSuffNull;
+    }
+
+    // TODO: remove this and just have java.text.DecimalFormat.hashCode do the right thing itself.
     @Override
     public int hashCode() {
-        return super.hashCode() * 37 + this.getPositivePrefix().hashCode();
+        return this.getPositivePrefix().hashCode();
     }
 
     @Override
     public Object clone() {
-        String pat = this.toPattern();
-        DecimalFormatSymbols sym = (DecimalFormatSymbols) this.symbols.clone();
-        DecimalFormat newdf = new DecimalFormat(pat, sym);
-        newdf.setMaximumIntegerDigits(this.getMaximumIntegerDigits());
-        newdf.setMaximumFractionDigits(this.getMaximumFractionDigits());
-        newdf.setMinimumIntegerDigits(this.getMinimumIntegerDigits());
-        newdf.setMinimumFractionDigits(this.getMinimumFractionDigits());
-        newdf.setGroupingUsed(this.isGroupingUsed());
-        newdf.setGroupingSize(this.getGroupingSize());
-        return newdf;
+        return new DecimalFormat(this);
     }
 
     @Override
+    protected void finalize() {
+        NativeDecimalFormat.closeDecimalFormatImpl(this.addr);
+    }
+
+    /**
+     * Note: this doesn't check that the underlying native DecimalFormat objects' configured
+     * native DecimalFormatSymbols objects are equal. It is assumed that the
+     * caller (java.text.DecimalFormat) will check the java.text.DecimalFormatSymbols objects
+     * instead, for performance.
+     * 
+     * This is also unreasonably expensive, calling down to JNI multiple times.
+     * 
+     * TODO: remove this and just have java.text.DecimalFormat.equals do the right thing itself.
+     */
+    @Override
     public boolean equals(Object object) {
         if (object == this) {
             return true;
@@ -89,39 +119,47 @@ public class DecimalFormat extends NumberFormat {
             return false;
         }
         DecimalFormat obj = (DecimalFormat) object;
-
-        if(obj.addr == this.addr) {
+        if (obj.addr == this.addr) {
             return true;
         }
+        return obj.toPattern().equals(this.toPattern()) &&
+                obj.isDecimalSeparatorAlwaysShown() == this.isDecimalSeparatorAlwaysShown() &&
+                obj.getGroupingSize() == this.getGroupingSize() &&
+                obj.getMultiplier() == this.getMultiplier() &&
+                obj.getNegativePrefix().equals(this.getNegativePrefix()) &&
+                obj.getNegativeSuffix().equals(this.getNegativeSuffix()) &&
+                obj.getPositivePrefix().equals(this.getPositivePrefix()) &&
+                obj.getPositiveSuffix().equals(this.getPositiveSuffix()) &&
+                obj.getMaximumIntegerDigits() == this.getMaximumIntegerDigits() &&
+                obj.getMaximumFractionDigits() == this.getMaximumFractionDigits() &&
+                obj.getMinimumIntegerDigits() == this.getMinimumIntegerDigits() &&
+                obj.getMinimumFractionDigits() == this.getMinimumFractionDigits() &&
+                obj.isGroupingUsed() == this.isGroupingUsed() &&
+                obj.getCurrency() == this.getCurrency();
+    }
 
-        boolean result = super.equals(object);
-
-
-        result &= obj.toPattern().equals(this.toPattern());
-        result &= obj.isDecimalSeparatorAlwaysShown() == this.isDecimalSeparatorAlwaysShown();
-        result &= obj.getGroupingSize() == this.getGroupingSize();
-        result &= obj.getMultiplier() == this.getMultiplier();
-        result &= obj.getNegativePrefix().equals(this.getNegativePrefix());
-        result &= obj.getNegativeSuffix().equals(this.getNegativeSuffix());
-        result &= obj.getPositivePrefix().equals(this.getPositivePrefix());
-        result &= obj.getPositiveSuffix().equals(this.getPositiveSuffix());
-        result &= obj.getMaximumIntegerDigits() == this.getMaximumIntegerDigits();
-        result &= obj.getMaximumFractionDigits() == this.getMaximumFractionDigits();
-        result &= obj.getMinimumIntegerDigits() == this.getMinimumIntegerDigits();
-        result &= obj.getMinimumFractionDigits() == this.getMinimumFractionDigits();
-        result &= obj.isGroupingUsed() == this.isGroupingUsed();
-        Currency objCurr = obj.getCurrency();
-        Currency thisCurr = this.getCurrency();
-        if(objCurr != null) {
-            result &= objCurr.getCurrencyCode().equals(thisCurr.getCurrencyCode());
-            result &= objCurr.getSymbol().equals(thisCurr.getSymbol());
-            result &= objCurr.getDefaultFractionDigits() == thisCurr.getDefaultFractionDigits();
-        } else {
-            result &= thisCurr == null;
-        }
-        result &= obj.getDecimalFormatSymbols().equals(this.getDecimalFormatSymbols());
+    /**
+     * Copies the java.text.DecimalFormatSymbols' settings into our native peer.
+     */
+    public void setDecimalFormatSymbols(final java.text.DecimalFormatSymbols dfs) {
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_CURRENCY_SYMBOL, dfs.getCurrencySymbol());
 
-        return result;
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_DECIMAL_SEPARATOR_SYMBOL, dfs.getDecimalSeparator());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_DIGIT_SYMBOL, dfs.getDigit());
+
+        char groupingSeparator = dfs.getGroupingSeparator();
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_GROUPING_SEPARATOR_SYMBOL, groupingSeparator);
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_MONETARY_GROUPING_SEPARATOR_SYMBOL, groupingSeparator);
+
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_INFINITY_SYMBOL, dfs.getInfinity());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_INTL_CURRENCY_SYMBOL, dfs.getInternationalCurrencySymbol());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_MINUS_SIGN_SYMBOL, dfs.getMinusSign());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_MONETARY_SEPARATOR_SYMBOL, dfs.getMonetaryDecimalSeparator());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_NAN_SYMBOL, dfs.getNaN());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_PATTERN_SEPARATOR_SYMBOL, dfs.getPatternSeparator());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_PERCENT_SYMBOL, dfs.getPercent());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_PERMILL_SYMBOL, dfs.getPerMill());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_ZERO_DIGIT_SYMBOL, dfs.getZeroDigit());
     }
 
     private BigDecimal applyMultiplier(BigDecimal valBigDecimal) {
@@ -132,7 +170,6 @@ public class DecimalFormat extends NumberFormat {
        return valBigDecimal.multiply(multiplierBigDecimal);
     }
 
-    @Override
     public StringBuffer format(Object value, StringBuffer buffer, FieldPosition field) {
         if (!(value instanceof Number)) {
             throw new IllegalArgumentException();
@@ -170,7 +207,6 @@ public class DecimalFormat extends NumberFormat {
         }
     }
 
-    @Override
     public StringBuffer format(long value, StringBuffer buffer, FieldPosition field) {
         if (buffer == null || field == null) {
             throw new NullPointerException();
@@ -180,7 +216,6 @@ public class DecimalFormat extends NumberFormat {
         return buffer;
     }
 
-    @Override
     public StringBuffer format(double value, StringBuffer buffer, FieldPosition field) {
         if (buffer == null || field == null) {
             throw new NullPointerException();
@@ -191,30 +226,13 @@ public class DecimalFormat extends NumberFormat {
     }
 
     public void applyLocalizedPattern(String pattern) {
-        if (pattern == null) {
-            throw new NullPointerException("pattern was null");
-        }
-        try {
-            NativeDecimalFormat.applyPatternImpl(this.addr, false, pattern);
-        } catch(RuntimeException re) {
-            throw new IllegalArgumentException(
-                    "applying localized pattern failed for pattern: " + pattern, re);
-        }
+        NativeDecimalFormat.applyPattern(this.addr, true, pattern);
     }
 
     public void applyPattern(String pattern) {
-        if (pattern == null) {
-            throw new NullPointerException("pattern was null");
-        }
-        try {
-            NativeDecimalFormat.applyPatternImpl(this.addr, false, pattern);
-        } catch(RuntimeException re) {
-            throw new IllegalArgumentException(
-                    "applying pattern failed for pattern: " + pattern, re);
-        }
+        NativeDecimalFormat.applyPattern(this.addr, false, pattern);
     }
 
-    @Override
     public AttributedCharacterIterator formatToCharacterIterator(Object object) {
         if (!(object instanceof Number)) {
             throw new IllegalArgumentException();
@@ -283,40 +301,38 @@ public class DecimalFormat extends NumberFormat {
         return NativeDecimalFormat.toPatternImpl(this.addr, false);
     }
 
-    @Override
     public Number parse(String string, ParsePosition position) {
         return NativeDecimalFormat.parse(addr, string, position);
     }
 
     // start getter and setter
 
-    @Override
     public int getMaximumFractionDigits() {
-        return NativeDecimalFormat.getAttribute(this .addr,
+        return NativeDecimalFormat.getAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_MAX_FRACTION_DIGITS.ordinal());
     }
 
-    @Override
     public int getMaximumIntegerDigits() {
-        return NativeDecimalFormat.getAttribute(this .addr,
+        return NativeDecimalFormat.getAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_MAX_INTEGER_DIGITS.ordinal());
     }
 
-    @Override
     public int getMinimumFractionDigits() {
-        return NativeDecimalFormat.getAttribute(this .addr,
+        return NativeDecimalFormat.getAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_MIN_FRACTION_DIGITS.ordinal());
     }
 
-    @Override
     public int getMinimumIntegerDigits() {
-        return NativeDecimalFormat.getAttribute(this .addr,
+        return NativeDecimalFormat.getAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_MIN_INTEGER_DIGITS.ordinal());
     }
 
-    @Override
     public Currency getCurrency() {
-        return this.symbols.getCurrency();
+        String curr = NativeDecimalFormat.getSymbol(this.addr, UNUM_INTL_CURRENCY_SYMBOL);
+        if (curr.equals("") || curr.equals("\u00a4\u00a4")) {
+            return null;
+        }
+        return Currency.getInstance(curr);
     }
 
     public int getGroupingSize() {
@@ -366,35 +382,25 @@ public class DecimalFormat extends NumberFormat {
                 UNumberFormatAttribute.UNUM_DECIMAL_ALWAYS_SHOWN.ordinal()) != 0;
     }
 
-    @Override
     public boolean isParseIntegerOnly() {
         return NativeDecimalFormat.getAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_PARSE_INT_ONLY.ordinal()) != 0;
     }
 
-    @Override
     public boolean isGroupingUsed() {
         return NativeDecimalFormat.getAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_GROUPING_USED.ordinal()) != 0;
     }
 
-    public DecimalFormatSymbols getDecimalFormatSymbols() {
-        return this.symbols;
-    }
-
-    public void setDecimalFormatSymbols(DecimalFormatSymbols icuSymbols) {
-        this.symbols = icuSymbols;
-    }
-
     public void setDecimalSeparatorAlwaysShown(boolean value) {
         int i = value ? -1 : 0;
         NativeDecimalFormat.setAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_DECIMAL_ALWAYS_SHOWN.ordinal(), i);
     }
 
-    @Override
     public void setCurrency(Currency currency) {
-        this.symbols.setCurrency(currency);
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_CURRENCY_SYMBOL, currency.getSymbol());
+        NativeDecimalFormat.setSymbol(this.addr, UNUM_INTL_CURRENCY_SYMBOL, currency.getCurrencyCode());
     }
 
     public void setGroupingSize(int value) {
@@ -402,32 +408,27 @@ public class DecimalFormat extends NumberFormat {
                 UNumberFormatAttribute.UNUM_GROUPING_SIZE.ordinal(), value);
     }
 
-    @Override
     public void setGroupingUsed(boolean value) {
         int i = value ? -1 : 0;
         NativeDecimalFormat.setAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_GROUPING_USED.ordinal(), i);
     }
 
-    @Override
     public void setMaximumFractionDigits(int value) {
         NativeDecimalFormat.setAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_MAX_FRACTION_DIGITS.ordinal(), value);
     }
 
-    @Override
     public void setMaximumIntegerDigits(int value) {
         NativeDecimalFormat.setAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_MAX_INTEGER_DIGITS.ordinal(), value);
     }
 
-    @Override
     public void setMinimumFractionDigits(int value) {
         NativeDecimalFormat.setAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_MIN_FRACTION_DIGITS.ordinal(), value);
     }
 
-    @Override
     public void setMinimumIntegerDigits(int value) {
         NativeDecimalFormat.setAttribute(this.addr,
                 UNumberFormatAttribute.UNUM_MIN_INTEGER_DIGITS.ordinal(), value);
@@ -476,7 +477,6 @@ public class DecimalFormat extends NumberFormat {
         }
     }
 
-    @Override
     public void setParseIntegerOnly(boolean value) {
         int i = value ? -1 : 0;
         NativeDecimalFormat.setAttribute(this.addr,
diff --git a/icu/src/main/java/com/ibm/icu4jni/text/DecimalFormatSymbols.java b/icu/src/main/java/com/ibm/icu4jni/text/DecimalFormatSymbols.java
deleted file mode 100644
index 2d5ae02..0000000
--- a/icu/src/main/java/com/ibm/icu4jni/text/DecimalFormatSymbols.java
+++ /dev/null
@@ -1,268 +0,0 @@
-/*
- * Copyright (C) 2008 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.ibm.icu4jni.text;
-
-import com.ibm.icu4jni.util.LocaleData;
-
-import java.security.AccessController;
-import java.security.PrivilegedAction;
-import java.util.Currency;
-import java.util.Locale;
-import java.util.ResourceBundle;
-
-public class DecimalFormatSymbols implements Cloneable {
-    
-    // Constants corresponding to the native type UNumberFormatSymbol, for use with getSymbol/setSymbol.
-    private static final int UNUM_DECIMAL_SEPARATOR_SYMBOL = 0;
-    private static final int UNUM_GROUPING_SEPARATOR_SYMBOL = 1;
-    private static final int UNUM_PATTERN_SEPARATOR_SYMBOL = 2;
-    private static final int UNUM_PERCENT_SYMBOL = 3;
-    private static final int UNUM_ZERO_DIGIT_SYMBOL = 4;
-    private static final int UNUM_DIGIT_SYMBOL = 5;
-    private static final int UNUM_MINUS_SIGN_SYMBOL = 6;
-    private static final int UNUM_PLUS_SIGN_SYMBOL = 7;
-    private static final int UNUM_CURRENCY_SYMBOL = 8;
-    private static final int UNUM_INTL_CURRENCY_SYMBOL = 9;
-    private static final int UNUM_MONETARY_SEPARATOR_SYMBOL = 10;
-    private static final int UNUM_EXPONENTIAL_SYMBOL = 11;
-    private static final int UNUM_PERMILL_SYMBOL = 12;
-    private static final int UNUM_PAD_ESCAPE_SYMBOL = 13;
-    private static final int UNUM_INFINITY_SYMBOL = 14;
-    private static final int UNUM_NAN_SYMBOL = 15;
-    private static final int UNUM_SIGNIFICANT_DIGIT_SYMBOL = 16;
-    private static final int UNUM_MONETARY_GROUPING_SEPARATOR_SYMBOL = 17;
-    private static final int UNUM_FORMAT_SYMBOL_COUNT = 18;
-
-    private final int addr;
-
-    // Used to implement clone.
-    private DecimalFormatSymbols(DecimalFormatSymbols other) {
-        this.addr = NativeDecimalFormat.cloneImpl(other.addr);
-    }
-    
-    public DecimalFormatSymbols(Locale locale) {
-        LocaleData localeData = com.ibm.icu4jni.util.Resources.getLocaleData(locale);
-        this.addr = NativeDecimalFormat.openDecimalFormatImpl(locale.toString(),
-                localeData.numberPattern);
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_CURRENCY_SYMBOL, localeData.currencySymbol);
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_INTL_CURRENCY_SYMBOL,
-                localeData.internationalCurrencySymbol);
-    }
-    
-    public DecimalFormatSymbols(Locale locale, java.text.DecimalFormatSymbols symbols) {
-        LocaleData localeData = com.ibm.icu4jni.util.Resources.getLocaleData(locale);
-        this.addr = NativeDecimalFormat.openDecimalFormatImpl(locale.toString(),
-                localeData.numberPattern);
-        copySymbols(symbols);
-    }
-    
-    /**
-     * Copies the java.text.DecimalFormatSymbols' settings into this object.
-     */
-    public void copySymbols(final java.text.DecimalFormatSymbols dfs) {
-        setCurrencySymbol(dfs.getCurrencySymbol());
-        setDecimalSeparator(dfs.getDecimalSeparator());
-        setDigit(dfs.getDigit());
-        setGroupingSeparator(dfs.getGroupingSeparator());
-        setInfinity(dfs.getInfinity());
-        setInternationalCurrencySymbol(dfs.getInternationalCurrencySymbol());
-        setMinusSign(dfs.getMinusSign());
-        setMonetaryDecimalSeparator(dfs.getMonetaryDecimalSeparator());
-        setNaN(dfs.getNaN());
-        setPatternSeparator(dfs.getPatternSeparator());
-        setPercent(dfs.getPercent());
-        setPerMill(dfs.getPerMill());
-        setZeroDigit(dfs.getZeroDigit());
-    }
-    
-    @Override
-    public boolean equals(Object object) {
-        if(object == null) {
-            return false;
-        }
-        if(!(object instanceof DecimalFormatSymbols)) {
-            return false;
-        }
-        
-        DecimalFormatSymbols sym = (DecimalFormatSymbols) object;
-        
-        if(sym.addr == this.addr) {
-            return true;
-        }
-        
-        boolean result = true;
-        
-        Currency objCurr = sym.getCurrency();
-        Currency thisCurr = this.getCurrency();
-        if(objCurr != null) {
-            result &= objCurr.getCurrencyCode().equals(thisCurr.getCurrencyCode());
-            result &= objCurr.getSymbol().equals(thisCurr.getSymbol());
-            result &= objCurr.getDefaultFractionDigits() == thisCurr.getDefaultFractionDigits();
-        } else {
-            result &= thisCurr == null;
-        }
-        result &= sym.getCurrencySymbol().equals(this.getCurrencySymbol());
-        result &= sym.getDecimalSeparator() == this.getDecimalSeparator();
-        result &= sym.getDigit() == this.getDigit();
-        result &= sym.getGroupingSeparator() == this.getGroupingSeparator();
-        result &= sym.getInfinity().equals(this.getInfinity());
-        result &= sym.getInternationalCurrencySymbol().equals(
-                this.getInternationalCurrencySymbol());
-        result &= sym.getMinusSign() == this.getMinusSign();
-        result &= sym.getMonetaryDecimalSeparator() == 
-                this.getMonetaryDecimalSeparator();
-        result &= sym.getNaN().equals(this.getNaN());
-        result &= sym.getPatternSeparator() == this.getPatternSeparator();
-        result &= sym.getPercent() == this.getPercent();
-        result &= sym.getPerMill() == this.getPerMill();
-        result &= sym.getZeroDigit() == this.getZeroDigit();
-        
-        return result;
-    }
-
-    @Override
-    public Object clone() {
-        return new DecimalFormatSymbols(this);
-    }
-    
-    public void setCurrency(Currency currency) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_CURRENCY_SYMBOL, currency.getSymbol());
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_INTL_CURRENCY_SYMBOL,
-                currency.getCurrencyCode());
-    }
-
-    public void setCurrencySymbol(String symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_CURRENCY_SYMBOL, symbol);
-    }
-
-    public void setDecimalSeparator(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_DECIMAL_SEPARATOR_SYMBOL, symbol);
-    }
-
-    public void setDigit(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_DIGIT_SYMBOL, symbol);
-    }
-
-    public void setGroupingSeparator(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_GROUPING_SEPARATOR_SYMBOL, symbol);
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_MONETARY_GROUPING_SEPARATOR_SYMBOL, symbol);
-    }
-
-    public void setInfinity(String symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_INFINITY_SYMBOL, symbol);
-    }
-
-    public void setInternationalCurrencySymbol(String symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_INTL_CURRENCY_SYMBOL, symbol);
-    }
-
-    public void setMinusSign(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_MINUS_SIGN_SYMBOL, symbol);
-    }
-
-    public void setMonetaryDecimalSeparator(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_MONETARY_SEPARATOR_SYMBOL, symbol);
-    }
-
-    public void setNaN(String symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_NAN_SYMBOL, symbol);
-    }
-
-    public void setPatternSeparator(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_PATTERN_SEPARATOR_SYMBOL, symbol);
-    }
-
-    public void setPercent(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_PERCENT_SYMBOL, symbol);
-    }
-
-    public void setPerMill(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_PERMILL_SYMBOL, symbol);
-    }
-
-    public void setZeroDigit(char symbol) {
-        NativeDecimalFormat.setSymbol(this.addr, UNUM_ZERO_DIGIT_SYMBOL, symbol);
-    }
- 
-    public Currency getCurrency() {
-        String curr = NativeDecimalFormat.getSymbol(this.addr, UNUM_INTL_CURRENCY_SYMBOL);
-        if (curr.equals("") || curr.equals("\u00a4\u00a4")) {
-            return null;
-        }
-        return Currency.getInstance(curr);
-    }
- 
-    public String getCurrencySymbol() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_CURRENCY_SYMBOL);
-    }
- 
-    public char getDecimalSeparator() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_DECIMAL_SEPARATOR_SYMBOL).charAt(0);
-    }
- 
-    public char getDigit() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_DIGIT_SYMBOL).charAt(0);
-    }
- 
-    public char getGroupingSeparator() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_GROUPING_SEPARATOR_SYMBOL).charAt(0);
-    }
- 
-    public String getInfinity() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_INFINITY_SYMBOL);
-    }
- 
-    public String getInternationalCurrencySymbol() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_INTL_CURRENCY_SYMBOL);
-    }
- 
-    public char getMinusSign() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_MINUS_SIGN_SYMBOL).charAt(0);
-    }
- 
-    public char getMonetaryDecimalSeparator() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_MONETARY_SEPARATOR_SYMBOL).charAt(0);
-    }
-
-    public String getNaN() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_NAN_SYMBOL);
-    }
- 
-    public char getPatternSeparator() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_PATTERN_SEPARATOR_SYMBOL).charAt(0);
-    }
- 
-    public char getPercent() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_PERCENT_SYMBOL).charAt(0);
-    }
- 
-    public char getPerMill() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_PERMILL_SYMBOL).charAt(0);
-    }
-
-    public char getZeroDigit() {
-        return NativeDecimalFormat.getSymbol(this.addr, UNUM_ZERO_DIGIT_SYMBOL).charAt(0);
-    }
-    
-    int getAddr() {
-        return this.addr;
-    }
-    
-    protected void finalize() {
-        NativeDecimalFormat.closeDecimalFormatImpl(this.addr);
-    }
-}
diff --git a/icu/src/main/java/com/ibm/icu4jni/text/NativeDecimalFormat.java b/icu/src/main/java/com/ibm/icu4jni/text/NativeDecimalFormat.java
index 88e0d5f..ec07fbd 100644
--- a/icu/src/main/java/com/ibm/icu4jni/text/NativeDecimalFormat.java
+++ b/icu/src/main/java/com/ibm/icu4jni/text/NativeDecimalFormat.java
@@ -55,15 +55,26 @@ final class NativeDecimalFormat {
         UNUM_PUBLIC_RULESETS
     }
     
-    static native int openDecimalFormatImpl(String locale, String pattern);
+    static int openDecimalFormat(String locale, String pattern) {
+        try {
+            // FIXME: if we're about to override everything, should we just ask for the cheapest locale (presumably the root locale)?
+            return NativeDecimalFormat.openDecimalFormatImpl(locale, pattern);
+        } catch (NullPointerException npe) {
+            throw npe;
+        } catch (RuntimeException re) {
+            throw new IllegalArgumentException("syntax error: " + re.getMessage() + ": " + pattern);
+        }
+    }
+    private static native int openDecimalFormatImpl(String locale, String pattern);
 
     static native void closeDecimalFormatImpl(int addr);
     
-    static native int cloneImpl(int addr);
+    static native int cloneDecimalFormatImpl(int addr);
     
     static native void setSymbol(int addr, int symbol, String str);
     static native void setSymbol(int addr, int symbol, char ch);
     
+    // FIXME: do we need this any more? the Java-side object should be the canonical source.
     static native String getSymbol(int addr, int symbol);
     
     static native void setAttribute(int addr, int symbol, int i);
@@ -74,7 +85,16 @@ final class NativeDecimalFormat {
 
     static native String getTextAttribute(int addr, int symbol);
 
-    static native void applyPatternImpl(int addr, boolean localized, String pattern);
+    static void applyPattern(int addr, boolean localized, String pattern) {
+        try {
+            NativeDecimalFormat.applyPatternImpl(addr, localized, pattern);
+        } catch (NullPointerException npe) {
+            throw npe;
+        } catch (RuntimeException re) {
+            throw new IllegalArgumentException("syntax error: " + re.getMessage() + ": " + pattern);
+        }
+    }
+    private static native void applyPatternImpl(int addr, boolean localized, String pattern);
 
     static native String toPatternImpl(int addr, boolean localized);