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32 package net.sf.retrotranslator.runtime.format;
33
34 import java.math.*;
35 import java.text.DecimalFormatSymbols  ;
36
37
40 abstract class FloatingPointConversion extends NumericConversion {
41
42 protected abstract void printf(FormatContext context, boolean negative, BigDecimal argument);
43
44 protected void printf(FormatContext context) {
45 Object argument = context.getArgument();
46 if (argument instanceof Double ) {
47 printf(context, (Double ) argument);
48 } else if (argument instanceof Float ) {
49 printf(context, (Float ) argument);
50 } else if (argument == null) {
51 context.writeRestricted(String.valueOf(argument));
52 } else if (argument instanceof BigDecimal) {
53 BigDecimal bigDecimal = (BigDecimal) argument;
54 printf(context, bigDecimal.signum() < 0, bigDecimal.abs());
55 } else {
56 throw context.getConversionException();
57 }
58 }
59
60 private void printf(FormatContext context, double argument) {
61 if (!printSpecialNumber(context, argument)) {
62 printf(context, Double.doubleToLongBits(argument) < 0, BigDecimal.valueOf(Math.abs(argument)));
63 }
64 }
65
66 protected static void printComputerizedScientificNumber(FormatContext context, boolean negative,
67 BigDecimal argument, int precision) {
68 String unscaled = argument.unscaledValue().toString();
69 StringBuilder builder = new StringBuilder ();
70 builder.append(unscaled.charAt(0));
71 if (precision > 0 || context.isFlag('#')) {
72 builder.append('.');
73 }
74 if (precision < unscaled.length()) {
75 builder.append(unscaled.substring(1, precision + 1));
76 } else {
77 builder.append(unscaled.substring(1));
78 appendZeros(builder, precision + 1 - unscaled.length());
79 }
80 int exponent = unscaled.equals("0") ? 0 : unscaled.length() - argument.scale() - 1;
81 builder.append('e').append(exponent < 0 ? '-' : '+');
82 int absoluteExponent = Math.abs(exponent);
83 if (absoluteExponent < 10) {
84 builder.append('0');
85 }
86 builder.append(absoluteExponent);
87 printNumber(context, negative, null, builder, context.getSymbols(false));
88 }
89
90 protected static void printDecimalNumber(FormatContext context, boolean negative,
91 BigDecimal argument, boolean localized) {
92 String unscaled = argument.unscaledValue().toString();
93 String integerPart = "0";
94 String fractionPart = "";
95 int separatorIndex = unscaled.length() - argument.scale();
96 if (separatorIndex < 0) {
97 fractionPart = appendZeros(new StringBuilder (), -separatorIndex).append(unscaled).toString();
98 } else if (separatorIndex == 0) {
99 fractionPart = unscaled;
100 } else if (separatorIndex < unscaled.length()) {
101 integerPart = unscaled.substring(0, separatorIndex);
102 fractionPart = unscaled.substring(separatorIndex);
103 } else if (separatorIndex == unscaled.length()) {
104 integerPart = unscaled;
105 } else {
106 integerPart = appendZeros(new StringBuilder (unscaled), separatorIndex - unscaled.length()).toString();
107 }
108 StringBuilder builder = new StringBuilder ();
109 DecimalFormatSymbols symbols = context.getSymbols(localized);
110 appendNumber(builder, integerPart, context.isFlag(','), symbols);
111 if (fractionPart.length() > 0 || context.isFlag('#')) {
112 builder.append(symbols.getDecimalSeparator());
113 }
114 appendNumber(builder, fractionPart, false, symbols);
115 printNumber(context, negative, null, builder, symbols);
116 }
117
118 protected static StringBuilder appendZeros(StringBuilder builder, int count) {
119 for (int i = 0; i < count; i++) {
120 builder.append('0');
121 }
122 return builder;
123 }
124
125 protected static BigDecimal round(BigDecimal decimal, int shift) {
126 int scale = decimal.scale() - shift;
127 return scale >= 0 ?
128 decimal.setScale(scale, BigDecimal.ROUND_HALF_UP) :
129 decimal.movePointRight(scale).setScale(0, BigDecimal.ROUND_HALF_UP).movePointLeft(scale);
130 }
131
132 public static class ComputerizedScientificConversion extends FloatingPointConversion {
133
134 public void format(FormatContext context) {
135 context.checkFlags();
136 context.assertNoFlag(',');
137 printf(context);
138 }
139
140 protected void printf(FormatContext context, boolean negative, BigDecimal argument) {
141 int shift = argument.unscaledValue().toString().length() - context.getNumberPrecision() - 1;
142 printComputerizedScientificNumber(context, negative, round(argument, shift), context.getNumberPrecision());
143 }
144 }
145
146 public static class DecimalConversion extends FloatingPointConversion {
147
148 public void format(FormatContext context) {
149 context.checkWidth();
150 context.checkFlags();
151 printf(context);
152 }
153
154 protected void printf(FormatContext context, boolean negative, BigDecimal argument) {
155 BigDecimal roundedArgument = argument.setScale(context.getNumberPrecision(), BigDecimal.ROUND_HALF_UP);
156 printDecimalNumber(context, negative, roundedArgument, true);
157 }
158 }
159
160 public static class GeneralScientificConversion extends FloatingPointConversion {
161
162 public void format(FormatContext context) {
163 context.checkFlags();
164 context.assertNoFlag('#');
165 printf(context);
166 }
167
168 protected void printf(FormatContext context, boolean negative, BigDecimal argument) {
169 int precision = Math.max(context.getNumberPrecision(), 1);
170 BigDecimal roundedArgument = round(argument, argument.unscaledValue().toString().length() - precision);
171 if (roundedArgument.compareTo(new BigDecimal(BigInteger.ONE, 4)) >= 0 &&
172 roundedArgument.compareTo(BigDecimal.ONE.movePointRight(precision)) < 0) {
173 printDecimalNumber(context, negative, roundedArgument, context.getArgument() instanceof BigDecimal);
174 } else {
175 printComputerizedScientificNumber(context, negative, roundedArgument, precision - 1);
176 }
177 }
178
179 }
180
181 }
182 |
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