1 | /*
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2 | * Licensed to the Apache Software Foundation (ASF) under one or more
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3 | * contributor license agreements. See the NOTICE file distributed with
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4 | * this work for additional information regarding copyright ownership.
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5 | * The ASF licenses this file to You under the Apache License, Version 2.0
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6 | * (the "License"); you may not use this file except in compliance with
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7 | * the License. You may obtain a copy of the License at
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8 | *
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9 | * http://www.apache.org/licenses/LICENSE-2.0
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10 | *
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11 | * Unless required by applicable law or agreed to in writing, software
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12 | * distributed under the License is distributed on an "AS IS" BASIS,
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13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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14 | * See the License for the specific language governing permissions and
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15 | * limitations under the License.
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16 | */
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17 | package agents.org.apache.commons.lang;
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18 |
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19 | import java.math.BigDecimal;
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20 | import java.math.BigInteger;
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21 |
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22 | /**
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23 | * <p>Provides extra functionality for Java Number classes.</p>
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24 | *
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25 | * @author Apache Software Foundation
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26 | * @author <a href="mailto:rand_mcneely@yahoo.com">Rand McNeely</a>
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27 | * @author <a href="mailto:steve.downey@netfolio.com">Steve Downey</a>
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28 | * @author Eric Pugh
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29 | * @author Phil Steitz
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30 | * @since 1.0
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31 | * @version $Id: NumberUtils.java 905636 2010-02-02 14:03:32Z niallp $
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32 | *
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33 | * @deprecated Moved to org.apache.commons.lang.math.
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34 | * Class will be removed in Commons Lang 3.0.
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35 | */
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36 | public final class NumberUtils {
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37 | // DEPRECATED CLASS !!!
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38 |
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39 | /**
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40 | * <p><code>NumberUtils</code> instances should NOT be constructed in standard programming.
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41 | * Instead, the class should be used as <code>NumberUtils.stringToInt("6");</code>.</p>
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42 | *
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43 | * <p>This constructor is public to permit tools that require a JavaBean instance
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44 | * to operate.</p>
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45 | */
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46 | public NumberUtils() {
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47 | super();
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48 | }
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49 |
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50 | //--------------------------------------------------------------------
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51 |
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52 | /**
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53 | * <p>Convert a <code>String</code> to an <code>int</code>, returning
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54 | * <code>zero</code> if the conversion fails.</p>
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55 | *
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56 | * @param str the string to convert
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57 | * @return the int represented by the string, or <code>zero</code> if
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58 | * conversion fails
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59 | */
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60 | public static int stringToInt(String str) {
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61 | return stringToInt(str, 0);
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62 | }
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63 |
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64 | /**
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65 | * <p>Convert a <code>String</code> to an <code>int</code>, returning a
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66 | * default value if the conversion fails.</p>
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67 | *
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68 | * @param str the string to convert
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69 | * @param defaultValue the default value
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70 | * @return the int represented by the string, or the default if conversion fails
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71 | */
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72 | public static int stringToInt(String str, int defaultValue) {
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73 | try {
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74 | return Integer.parseInt(str);
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75 | } catch (NumberFormatException nfe) {
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76 | return defaultValue;
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77 | }
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78 | }
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79 |
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80 | //--------------------------------------------------------------------
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81 |
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82 | // must handle Long, Float, Integer, Float, Short,
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83 | // BigDecimal, BigInteger and Byte
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84 | // useful methods:
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85 | // Byte.decode(String)
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86 | // Byte.valueOf(String,int radix)
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87 | // Byte.valueOf(String)
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88 | // Double.valueOf(String)
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89 | // Float.valueOf(String)
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90 | // new Float(String)
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91 | // Integer.valueOf(String,int radix)
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92 | // Integer.valueOf(String)
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93 | // Integer.decode(String)
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94 | // Integer.getInteger(String)
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95 | // Integer.getInteger(String,int val)
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96 | // Integer.getInteger(String,Integer val)
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97 | // new Integer(String)
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98 | // new Double(String)
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99 | // new Byte(String)
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100 | // new Long(String)
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101 | // Long.getLong(String)
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102 | // Long.getLong(String,int)
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103 | // Long.getLong(String,Integer)
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104 | // Long.valueOf(String,int)
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105 | // Long.valueOf(String)
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106 | // new Short(String)
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107 | // Short.decode(String)
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108 | // Short.valueOf(String,int)
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109 | // Short.valueOf(String)
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110 | // new BigDecimal(String)
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111 | // new BigInteger(String)
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112 | // new BigInteger(String,int radix)
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113 | // Possible inputs:
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114 | // 45 45.5 45E7 4.5E7 Hex Oct Binary xxxF xxxD xxxf xxxd
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115 | // plus minus everything. Prolly more. A lot are not separable.
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116 |
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117 | /**
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118 | * <p>Turns a string value into a java.lang.Number.</p>
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119 | *
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120 | * <p>First, the value is examined for a type qualifier on the end
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121 | * (<code>'f','F','d','D','l','L'</code>). If it is found, it starts
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122 | * trying to create successively larger types from the type specified
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123 | * until one is found that can hold the value.</p>
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124 | *
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125 | * <p>If a type specifier is not found, it will check for a decimal point
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126 | * and then try successively larger types from <code>Integer</code> to
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127 | * <code>BigInteger</code> and from <code>Float</code> to
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128 | * <code>BigDecimal</code>.</p>
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129 | *
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130 | * <p>If the string starts with <code>0x</code> or <code>-0x</code>, it
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131 | * will be interpreted as a hexadecimal integer. Values with leading
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132 | * <code>0</code>'s will not be interpreted as octal.</p>
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133 | *
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134 | * @param val String containing a number
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135 | * @return Number created from the string
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136 | * @throws NumberFormatException if the value cannot be converted
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137 | */
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138 | public static Number createNumber(String val) throws NumberFormatException {
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139 | if (val == null) {
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140 | return null;
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141 | }
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142 | if (val.length() == 0) {
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143 | throw new NumberFormatException("\"\" is not a valid number.");
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144 | }
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145 | if (val.length() == 1 && !Character.isDigit(val.charAt(0))) {
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146 | throw new NumberFormatException(val + " is not a valid number.");
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147 | }
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148 | if (val.startsWith("--")) {
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149 | // this is protection for poorness in java.lang.BigDecimal.
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150 | // it accepts this as a legal value, but it does not appear
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151 | // to be in specification of class. OS X Java parses it to
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152 | // a wrong value.
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153 | return null;
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154 | }
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155 | if (val.startsWith("0x") || val.startsWith("-0x")) {
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156 | return createInteger(val);
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157 | }
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158 | char lastChar = val.charAt(val.length() - 1);
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159 | String mant;
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160 | String dec;
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161 | String exp;
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162 | int decPos = val.indexOf('.');
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163 | int expPos = val.indexOf('e') + val.indexOf('E') + 1;
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164 |
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165 | if (decPos > -1) {
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166 |
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167 | if (expPos > -1) {
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168 | if (expPos < decPos) {
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169 | throw new NumberFormatException(val + " is not a valid number.");
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170 | }
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171 | dec = val.substring(decPos + 1, expPos);
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172 | } else {
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173 | dec = val.substring(decPos + 1);
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174 | }
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175 | mant = val.substring(0, decPos);
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176 | } else {
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177 | if (expPos > -1) {
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178 | mant = val.substring(0, expPos);
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179 | } else {
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180 | mant = val;
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181 | }
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182 | dec = null;
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183 | }
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184 | if (!Character.isDigit(lastChar)) {
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185 | if (expPos > -1 && expPos < val.length() - 1) {
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186 | exp = val.substring(expPos + 1, val.length() - 1);
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187 | } else {
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188 | exp = null;
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189 | }
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190 | //Requesting a specific type..
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191 | String numeric = val.substring(0, val.length() - 1);
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192 | boolean allZeros = isAllZeros(mant) && isAllZeros(exp);
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193 | switch (lastChar) {
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194 | case 'l' :
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195 | case 'L' :
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196 | if (dec == null
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197 | && exp == null
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198 | && (numeric.charAt(0) == '-' && isDigits(numeric.substring(1)) || isDigits(numeric))) {
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199 | try {
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200 | return createLong(numeric);
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201 | } catch (NumberFormatException nfe) {
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202 | //Too big for a long
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203 | }
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204 | return createBigInteger(numeric);
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205 |
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206 | }
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207 | throw new NumberFormatException(val + " is not a valid number.");
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208 | case 'f' :
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209 | case 'F' :
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210 | try {
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211 | Float f = NumberUtils.createFloat(numeric);
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212 | if (!(f.isInfinite() || (f.floatValue() == 0.0F && !allZeros))) {
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213 | //If it's too big for a float or the float value = 0 and the string
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214 | //has non-zeros in it, then float does not have the precision we want
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215 | return f;
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216 | }
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217 |
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218 | } catch (NumberFormatException e) {
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219 | // ignore the bad number
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220 | }
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221 | //$FALL-THROUGH$
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222 | case 'd' :
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223 | case 'D' :
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224 | try {
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225 | Double d = NumberUtils.createDouble(numeric);
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226 | if (!(d.isInfinite() || (d.floatValue() == 0.0D && !allZeros))) {
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227 | return d;
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228 | }
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229 | } catch (NumberFormatException nfe) {
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230 | // empty catch
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231 | }
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232 | try {
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233 | return createBigDecimal(numeric);
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234 | } catch (NumberFormatException e) {
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235 | // empty catch
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236 | }
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237 | //$FALL-THROUGH$
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238 | default :
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239 | throw new NumberFormatException(val + " is not a valid number.");
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240 |
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241 | }
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242 | } else {
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243 | //User doesn't have a preference on the return type, so let's start
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244 | //small and go from there...
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245 | if (expPos > -1 && expPos < val.length() - 1) {
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246 | exp = val.substring(expPos + 1, val.length());
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247 | } else {
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248 | exp = null;
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249 | }
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250 | if (dec == null && exp == null) {
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251 | //Must be an int,long,bigint
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252 | try {
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253 | return createInteger(val);
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254 | } catch (NumberFormatException nfe) {
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255 | // empty catch
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256 | }
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257 | try {
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258 | return createLong(val);
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259 | } catch (NumberFormatException nfe) {
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260 | // empty catch
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261 | }
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262 | return createBigInteger(val);
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263 |
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264 | } else {
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265 | //Must be a float,double,BigDec
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266 | boolean allZeros = isAllZeros(mant) && isAllZeros(exp);
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267 | try {
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268 | Float f = createFloat(val);
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269 | if (!(f.isInfinite() || (f.floatValue() == 0.0F && !allZeros))) {
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270 | return f;
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271 | }
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272 | } catch (NumberFormatException nfe) {
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273 | // empty catch
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274 | }
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275 | try {
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276 | Double d = createDouble(val);
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277 | if (!(d.isInfinite() || (d.doubleValue() == 0.0D && !allZeros))) {
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278 | return d;
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279 | }
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280 | } catch (NumberFormatException nfe) {
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281 | // empty catch
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282 | }
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283 |
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284 | return createBigDecimal(val);
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285 |
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286 | }
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287 |
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288 | }
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289 | }
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290 |
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291 | /**
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292 | * <p>Utility method for {@link #createNumber(java.lang.String)}.</p>
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293 | *
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294 | * <p>Returns <code>true</code> if s is <code>null</code>.</p>
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295 | *
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296 | * @param s the String to check
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297 | * @return if it is all zeros or <code>null</code>
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298 | */
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299 | private static boolean isAllZeros(String s) {
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300 | if (s == null) {
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301 | return true;
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302 | }
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303 | for (int i = s.length() - 1; i >= 0; i--) {
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304 | if (s.charAt(i) != '0') {
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305 | return false;
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306 | }
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307 | }
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308 | return s.length() > 0;
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309 | }
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310 |
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311 | //--------------------------------------------------------------------
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312 |
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313 | /**
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314 | * <p>Convert a <code>String</code> to a <code>Float</code>.</p>
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315 | *
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316 | * @param val a <code>String</code> to convert
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317 | * @return converted <code>Float</code>
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318 | * @throws NumberFormatException if the value cannot be converted
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319 | */
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320 | public static Float createFloat(String val) {
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321 | return Float.valueOf(val);
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322 | }
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323 |
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324 | /**
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325 | * <p>Convert a <code>String</code> to a <code>Double</code>.</p>
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326 | *
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327 | * @param val a <code>String</code> to convert
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328 | * @return converted <code>Double</code>
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329 | * @throws NumberFormatException if the value cannot be converted
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330 | */
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331 | public static Double createDouble(String val) {
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332 | return Double.valueOf(val);
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333 | }
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334 |
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335 | /**
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336 | * <p>Convert a <code>String</code> to a <code>Integer</code>, handling
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337 | * hex and octal notations.</p>
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338 | *
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339 | * @param val a <code>String</code> to convert
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340 | * @return converted <code>Integer</code>
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341 | * @throws NumberFormatException if the value cannot be converted
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342 | */
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343 | public static Integer createInteger(String val) {
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344 | // decode() handles 0xAABD and 0777 (hex and octal) as well.
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345 | return Integer.decode(val);
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346 | }
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347 |
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348 | /**
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349 | * <p>Convert a <code>String</code> to a <code>Long</code>.</p>
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350 | *
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351 | * @param val a <code>String</code> to convert
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352 | * @return converted <code>Long</code>
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353 | * @throws NumberFormatException if the value cannot be converted
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354 | */
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355 | public static Long createLong(String val) {
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356 | return Long.valueOf(val);
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357 | }
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358 |
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359 | /**
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360 | * <p>Convert a <code>String</code> to a <code>BigInteger</code>.</p>
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361 | *
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362 | * @param val a <code>String</code> to convert
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363 | * @return converted <code>BigInteger</code>
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364 | * @throws NumberFormatException if the value cannot be converted
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365 | */
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366 | public static BigInteger createBigInteger(String val) {
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367 | BigInteger bi = new BigInteger(val);
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368 | return bi;
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369 | }
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370 |
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371 | /**
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372 | * <p>Convert a <code>String</code> to a <code>BigDecimal</code>.</p>
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373 | *
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374 | * @param val a <code>String</code> to convert
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375 | * @return converted <code>BigDecimal</code>
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376 | * @throws NumberFormatException if the value cannot be converted
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377 | */
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378 | public static BigDecimal createBigDecimal(String val) {
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379 | BigDecimal bd = new BigDecimal(val);
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380 | return bd;
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381 | }
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382 |
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383 | //--------------------------------------------------------------------
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384 |
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385 | /**
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386 | * <p>Gets the minimum of three <code>long</code> values.</p>
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387 | *
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388 | * @param a value 1
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389 | * @param b value 2
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390 | * @param c value 3
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391 | * @return the smallest of the values
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392 | */
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393 | public static long minimum(long a, long b, long c) {
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394 | if (b < a) {
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395 | a = b;
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396 | }
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397 | if (c < a) {
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398 | a = c;
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399 | }
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400 | return a;
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401 | }
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402 |
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403 | /**
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404 | * <p>Gets the minimum of three <code>int</code> values.</p>
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405 | *
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406 | * @param a value 1
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407 | * @param b value 2
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408 | * @param c value 3
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409 | * @return the smallest of the values
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410 | */
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411 | public static int minimum(int a, int b, int c) {
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412 | if (b < a) {
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413 | a = b;
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414 | }
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415 | if (c < a) {
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416 | a = c;
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417 | }
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418 | return a;
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419 | }
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420 |
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421 | /**
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422 | * <p>Gets the maximum of three <code>long</code> values.</p>
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423 | *
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424 | * @param a value 1
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425 | * @param b value 2
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426 | * @param c value 3
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427 | * @return the largest of the values
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428 | */
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429 | public static long maximum(long a, long b, long c) {
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430 | if (b > a) {
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431 | a = b;
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432 | }
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433 | if (c > a) {
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434 | a = c;
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435 | }
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436 | return a;
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437 | }
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438 |
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439 | /**
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440 | * <p>Gets the maximum of three <code>int</code> values.</p>
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441 | *
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442 | * @param a value 1
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443 | * @param b value 2
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444 | * @param c value 3
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445 | * @return the largest of the values
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446 | */
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447 | public static int maximum(int a, int b, int c) {
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448 | if (b > a) {
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449 | a = b;
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450 | }
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451 | if (c > a) {
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452 | a = c;
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453 | }
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454 | return a;
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455 | }
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456 |
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457 | //--------------------------------------------------------------------
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458 |
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459 | /**
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460 | * <p>Compares two <code>doubles</code> for order.</p>
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461 | *
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462 | * <p>This method is more comprehensive than the standard Java greater
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463 | * than, less than and equals operators.</p>
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464 | * <ul>
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465 | * <li>It returns <code>-1</code> if the first value is less than the second.
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466 | * <li>It returns <code>+1</code> if the first value is greater than the second.
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467 | * <li>It returns <code>0</code> if the values are equal.
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468 | * </ul>
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469 | *
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470 | * <p>
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471 | * The ordering is as follows, largest to smallest:
|
---|
472 | * <ul>
|
---|
473 | * <li>NaN
|
---|
474 | * <li>Positive infinity
|
---|
475 | * <li>Maximum double
|
---|
476 | * <li>Normal positive numbers
|
---|
477 | * <li>+0.0
|
---|
478 | * <li>-0.0
|
---|
479 | * <li>Normal negative numbers
|
---|
480 | * <li>Minimum double (-Double.MAX_VALUE)
|
---|
481 | * <li>Negative infinity
|
---|
482 | * </ul>
|
---|
483 | * </p>
|
---|
484 | *
|
---|
485 | * <p>Comparing <code>NaN</code> with <code>NaN</code> will
|
---|
486 | * return <code>0</code>.</p>
|
---|
487 | *
|
---|
488 | * @param lhs the first <code>double</code>
|
---|
489 | * @param rhs the second <code>double</code>
|
---|
490 | * @return <code>-1</code> if lhs is less, <code>+1</code> if greater,
|
---|
491 | * <code>0</code> if equal to rhs
|
---|
492 | */
|
---|
493 | public static int compare(double lhs, double rhs) {
|
---|
494 | if (lhs < rhs) {
|
---|
495 | return -1;
|
---|
496 | }
|
---|
497 | if (lhs > rhs) {
|
---|
498 | return +1;
|
---|
499 | }
|
---|
500 | // Need to compare bits to handle 0.0 == -0.0 being true
|
---|
501 | // compare should put -0.0 < +0.0
|
---|
502 | // Two NaNs are also == for compare purposes
|
---|
503 | // where NaN == NaN is false
|
---|
504 | long lhsBits = Double.doubleToLongBits(lhs);
|
---|
505 | long rhsBits = Double.doubleToLongBits(rhs);
|
---|
506 | if (lhsBits == rhsBits) {
|
---|
507 | return 0;
|
---|
508 | }
|
---|
509 | // Something exotic! A comparison to NaN or 0.0 vs -0.0
|
---|
510 | // Fortunately NaN's long is > than everything else
|
---|
511 | // Also negzeros bits < poszero
|
---|
512 | // NAN: 9221120237041090560
|
---|
513 | // MAX: 9218868437227405311
|
---|
514 | // NEGZERO: -9223372036854775808
|
---|
515 | if (lhsBits < rhsBits) {
|
---|
516 | return -1;
|
---|
517 | } else {
|
---|
518 | return +1;
|
---|
519 | }
|
---|
520 | }
|
---|
521 |
|
---|
522 | /**
|
---|
523 | * <p>Compares two floats for order.</p>
|
---|
524 | *
|
---|
525 | * <p>This method is more comprehensive than the standard Java greater than,
|
---|
526 | * less than and equals operators.</p>
|
---|
527 | * <ul>
|
---|
528 | * <li>It returns <code>-1</code> if the first value is less than the second.
|
---|
529 | * <li>It returns <code>+1</code> if the first value is greater than the second.
|
---|
530 | * <li>It returns <code>0</code> if the values are equal.
|
---|
531 | * </ul>
|
---|
532 | *
|
---|
533 | * <p> The ordering is as follows, largest to smallest:
|
---|
534 | * <ul>
|
---|
535 | * <li>NaN
|
---|
536 | * <li>Positive infinity
|
---|
537 | * <li>Maximum float
|
---|
538 | * <li>Normal positive numbers
|
---|
539 | * <li>+0.0
|
---|
540 | * <li>-0.0
|
---|
541 | * <li>Normal negative numbers
|
---|
542 | * <li>Minimum float (-Float.MAX_VALUE)
|
---|
543 | * <li>Negative infinity
|
---|
544 | * </ul>
|
---|
545 | *
|
---|
546 | * <p>Comparing <code>NaN</code> with <code>NaN</code> will return
|
---|
547 | * <code>0</code>.</p>
|
---|
548 | *
|
---|
549 | * @param lhs the first <code>float</code>
|
---|
550 | * @param rhs the second <code>float</code>
|
---|
551 | * @return <code>-1</code> if lhs is less, <code>+1</code> if greater,
|
---|
552 | * <code>0</code> if equal to rhs
|
---|
553 | */
|
---|
554 | public static int compare(float lhs, float rhs) {
|
---|
555 | if (lhs < rhs) {
|
---|
556 | return -1;
|
---|
557 | }
|
---|
558 | if (lhs > rhs) {
|
---|
559 | return +1;
|
---|
560 | }
|
---|
561 | //Need to compare bits to handle 0.0 == -0.0 being true
|
---|
562 | // compare should put -0.0 < +0.0
|
---|
563 | // Two NaNs are also == for compare purposes
|
---|
564 | // where NaN == NaN is false
|
---|
565 | int lhsBits = Float.floatToIntBits(lhs);
|
---|
566 | int rhsBits = Float.floatToIntBits(rhs);
|
---|
567 | if (lhsBits == rhsBits) {
|
---|
568 | return 0;
|
---|
569 | }
|
---|
570 | //Something exotic! A comparison to NaN or 0.0 vs -0.0
|
---|
571 | //Fortunately NaN's int is > than everything else
|
---|
572 | //Also negzeros bits < poszero
|
---|
573 | //NAN: 2143289344
|
---|
574 | //MAX: 2139095039
|
---|
575 | //NEGZERO: -2147483648
|
---|
576 | if (lhsBits < rhsBits) {
|
---|
577 | return -1;
|
---|
578 | } else {
|
---|
579 | return +1;
|
---|
580 | }
|
---|
581 | }
|
---|
582 |
|
---|
583 | //--------------------------------------------------------------------
|
---|
584 |
|
---|
585 | /**
|
---|
586 | * <p>Checks whether the <code>String</code> contains only
|
---|
587 | * digit characters.</p>
|
---|
588 | *
|
---|
589 | * <p><code>Null</code> and empty String will return
|
---|
590 | * <code>false</code>.</p>
|
---|
591 | *
|
---|
592 | * @param str the <code>String</code> to check
|
---|
593 | * @return <code>true</code> if str contains only unicode numeric
|
---|
594 | */
|
---|
595 | public static boolean isDigits(String str) {
|
---|
596 | if ((str == null) || (str.length() == 0)) {
|
---|
597 | return false;
|
---|
598 | }
|
---|
599 | for (int i = 0; i < str.length(); i++) {
|
---|
600 | if (!Character.isDigit(str.charAt(i))) {
|
---|
601 | return false;
|
---|
602 | }
|
---|
603 | }
|
---|
604 | return true;
|
---|
605 | }
|
---|
606 |
|
---|
607 | /**
|
---|
608 | * <p>Checks whether the String a valid Java number.</p>
|
---|
609 | *
|
---|
610 | * <p>Valid numbers include hexadecimal marked with the <code>0x</code>
|
---|
611 | * qualifier, scientific notation and numbers marked with a type
|
---|
612 | * qualifier (e.g. 123L).</p>
|
---|
613 | *
|
---|
614 | * <p><code>Null</code> and empty String will return
|
---|
615 | * <code>false</code>.</p>
|
---|
616 | *
|
---|
617 | * @param str the <code>String</code> to check
|
---|
618 | * @return <code>true</code> if the string is a correctly formatted number
|
---|
619 | */
|
---|
620 | public static boolean isNumber(String str) {
|
---|
621 | if (StringUtils.isEmpty(str)) {
|
---|
622 | return false;
|
---|
623 | }
|
---|
624 | char[] chars = str.toCharArray();
|
---|
625 | int sz = chars.length;
|
---|
626 | boolean hasExp = false;
|
---|
627 | boolean hasDecPoint = false;
|
---|
628 | boolean allowSigns = false;
|
---|
629 | boolean foundDigit = false;
|
---|
630 | // deal with any possible sign up front
|
---|
631 | int start = (chars[0] == '-') ? 1 : 0;
|
---|
632 | if (sz > start + 1) {
|
---|
633 | if (chars[start] == '0' && chars[start + 1] == 'x') {
|
---|
634 | int i = start + 2;
|
---|
635 | if (i == sz) {
|
---|
636 | return false; // str == "0x"
|
---|
637 | }
|
---|
638 | // checking hex (it can't be anything else)
|
---|
639 | for (; i < chars.length; i++) {
|
---|
640 | if ((chars[i] < '0' || chars[i] > '9')
|
---|
641 | && (chars[i] < 'a' || chars[i] > 'f')
|
---|
642 | && (chars[i] < 'A' || chars[i] > 'F')) {
|
---|
643 | return false;
|
---|
644 | }
|
---|
645 | }
|
---|
646 | return true;
|
---|
647 | }
|
---|
648 | }
|
---|
649 | sz--; // don't want to loop to the last char, check it afterwords
|
---|
650 | // for type qualifiers
|
---|
651 | int i = start;
|
---|
652 | // loop to the next to last char or to the last char if we need another digit to
|
---|
653 | // make a valid number (e.g. chars[0..5] = "1234E")
|
---|
654 | while (i < sz || (i < sz + 1 && allowSigns && !foundDigit)) {
|
---|
655 | if (chars[i] >= '0' && chars[i] <= '9') {
|
---|
656 | foundDigit = true;
|
---|
657 | allowSigns = false;
|
---|
658 |
|
---|
659 | } else if (chars[i] == '.') {
|
---|
660 | if (hasDecPoint || hasExp) {
|
---|
661 | // two decimal points or dec in exponent
|
---|
662 | return false;
|
---|
663 | }
|
---|
664 | hasDecPoint = true;
|
---|
665 | } else if (chars[i] == 'e' || chars[i] == 'E') {
|
---|
666 | // we've already taken care of hex.
|
---|
667 | if (hasExp) {
|
---|
668 | // two E's
|
---|
669 | return false;
|
---|
670 | }
|
---|
671 | if (!foundDigit) {
|
---|
672 | return false;
|
---|
673 | }
|
---|
674 | hasExp = true;
|
---|
675 | allowSigns = true;
|
---|
676 | } else if (chars[i] == '+' || chars[i] == '-') {
|
---|
677 | if (!allowSigns) {
|
---|
678 | return false;
|
---|
679 | }
|
---|
680 | allowSigns = false;
|
---|
681 | foundDigit = false; // we need a digit after the E
|
---|
682 | } else {
|
---|
683 | return false;
|
---|
684 | }
|
---|
685 | i++;
|
---|
686 | }
|
---|
687 | if (i < chars.length) {
|
---|
688 | if (chars[i] >= '0' && chars[i] <= '9') {
|
---|
689 | // no type qualifier, OK
|
---|
690 | return true;
|
---|
691 | }
|
---|
692 | if (chars[i] == 'e' || chars[i] == 'E') {
|
---|
693 | // can't have an E at the last byte
|
---|
694 | return false;
|
---|
695 | }
|
---|
696 | if (!allowSigns
|
---|
697 | && (chars[i] == 'd'
|
---|
698 | || chars[i] == 'D'
|
---|
699 | || chars[i] == 'f'
|
---|
700 | || chars[i] == 'F')) {
|
---|
701 | return foundDigit;
|
---|
702 | }
|
---|
703 | if (chars[i] == 'l'
|
---|
704 | || chars[i] == 'L') {
|
---|
705 | // not allowing L with an exponent
|
---|
706 | return foundDigit && !hasExp;
|
---|
707 | }
|
---|
708 | // last character is illegal
|
---|
709 | return false;
|
---|
710 | }
|
---|
711 | // allowSigns is true iff the val ends in 'E'
|
---|
712 | // found digit it to make sure weird stuff like '.' and '1E-' doesn't pass
|
---|
713 | return !allowSigns && foundDigit;
|
---|
714 | }
|
---|
715 | }
|
---|