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1: /* BigDecimalHelper.java -- 2: Copyright (C) 2005 Free Software Foundation, Inc. 3: 4: This file is part of GNU Classpath. 5: 6: GNU Classpath is free software; you can redistribute it and/or modify 7: it under the terms of the GNU General Public License as published by 8: the Free Software Foundation; either version 2, or (at your option) 9: any later version. 10: 11: GNU Classpath is distributed in the hope that it will be useful, but 12: WITHOUT ANY WARRANTY; without even the implied warranty of 13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14: General Public License for more details. 15: 16: You should have received a copy of the GNU General Public License 17: along with GNU Classpath; see the file COPYING. If not, write to the 18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 19: 02110-1301 USA. 20: 21: Linking this library statically or dynamically with other modules is 22: making a combined work based on this library. Thus, the terms and 23: conditions of the GNU General Public License cover the whole 24: combination. 25: 26: As a special exception, the copyright holders of this library give you 27: permission to link this library with independent modules to produce an 28: executable, regardless of the license terms of these independent 29: modules, and to copy and distribute the resulting executable under 30: terms of your choice, provided that you also meet, for each linked 31: independent module, the terms and conditions of the license of that 32: module. An independent module is a module which is not derived from 33: or based on this library. If you modify this library, you may extend 34: this exception to your version of the library, but you are not 35: obligated to do so. If you do not wish to do so, delete this 36: exception statement from your version. */ 37: 38: 39: package gnu.CORBA; 40: 41: import java.io.ByteArrayInputStream; 42: import java.io.ByteArrayOutputStream; 43: import java.io.IOException; 44: 45: import java.math.BigDecimal; 46: import java.math.BigInteger; 47: 48: import org.omg.CORBA.TypeCode; 49: import org.omg.CORBA.TypeCodePackage.BadKind; 50: 51: /** 52: * Reads and writes BigDecimal as CORBA <code>fixed</code>. 53: * The format, described in CORBA specification, requires to store 54: * data in hexadecimal format, two digits per byte (oceted), most 55: * significant digit first. The last half-byte in the representation 56: * stores the sign, being 0xD for negative numbers and 0xC for 57: * zero and positive numbers. To have the even number of half bytes, 58: * 0x0 is appended to the beginning, if required. The position of the 59: * decimal point is not stored. 60: * 61: * @author Audrius Meskauskas (AudriusA@Bioinformatics.org) 62: */ 63: public class BigDecimalHelper 64: { 65: { 66: } 67: 68: /** 69: * @todo remove from the release version. 70: */ 71: public static void main(String[] args) 72: { 73: try 74: { 75: ByteArrayOutputStream b = new ByteArrayOutputStream(); 76: BigDecimal d = new BigDecimal("12234.54689"); 77: 78: write(b, d); 79: 80: byte[] a = b.toByteArray(); 81: 82: for (int i = 0; i < a.length; i++) 83: { 84: int k = a [ i ] & 0xFF; 85: System.out.print(Integer.toHexString(k) + " "); 86: } 87: 88: System.out.println("Now reading"); 89: 90: ByteArrayInputStream bin = new ByteArrayInputStream(a); 91: 92: BigDecimal r = read(bin, d.scale()); 93: 94: System.out.println(r); 95: } 96: catch (Exception ex) 97: { 98: ex.printStackTrace(); 99: } 100: } 101: 102: /** 103: * Read the CORBA fixed, autodetecting the number of bytes 104: * and assuming the given scale. 105: */ 106: public static BigDecimal read(java.io.InputStream in, int scale) 107: throws IOException 108: { 109: ByteArrayOutputStream bout = new ByteArrayOutputStream(); 110: 111: int f; 112: 113: do 114: { 115: f = in.read(); 116: if (f >= 0) 117: bout.write(f); 118: } 119: // The last byte has 0xC or 0xD in the last halfbyte. 120: while ((f & 0xF) <= 0x9); 121: 122: return createFixed(scale, bout.toByteArray()); 123: } 124: 125: /** 126: * Write the big decimal as CORBA <code>fixed<.code>. 127: * The scale will not be stored. 128: * 129: * @param out a stream to write into. 130: * @param x a big decimal to write. 131: * @param digits a number of the decimal digits in the record 132: * being written. For the smaller 133: * numbers, zeroes are added to the left. 134: * 135: * @throws IOException if the stream write method throws one. 136: * @throws BadKind if this BigDecimal has more digits than 137: * specified. 138: */ 139: public static void write(java.io.OutputStream out, BigDecimal x) 140: throws IOException, BadKind 141: { 142: StringBuffer v = new StringBuffer(x.unscaledValue().toString()); 143: 144: boolean negative = v.charAt(0) == '-'; 145: 146: if (negative) 147: v = v.deleteCharAt(0); 148: 149: if ( (v.length() & 1) == 0) 150: v.insert(0, '0'); 151: 152: int c; 153: 154: for (int i = 0; i < v.length() - 1; i = i + 2) 155: { 156: c = ((v.charAt(i) - '0') << 4) | (v.charAt(i + 1) - '0'); 157: out.write(c); 158: } 159: 160: c = ((v.charAt(v.length() - 1) - '0') << 4) | (negative ? 0xD : 0xC); 161: 162: out.write(c); 163: } 164: 165: /** 166: * Convert the loaded byte array, representing 167: * CORBA <code>fixed</code>, into an instance of 168: * the {@link BigDecimal} 169: */ 170: private static BigDecimal createFixed(int scale, byte[] d) 171: { 172: StringBuffer s = new StringBuffer(2 * d.length); 173: 174: int last = d.length - 1; 175: 176: if ((d [ last ] & 0xF) == 0xD) 177: s.append('-'); 178: 179: if (last > 0) 180: for (int i = 0; i < last; i++) 181: { 182: s.append((char) (((d [ i ] >> 4) & 0xF) + '0')); 183: s.append((char) (((d [ i ]) & 0xF) + '0')); 184: } 185: 186: s.append((char) (((d [ last ] >> 4) & 0xF) + '0')); 187: 188: BigInteger b = new BigInteger(s.toString()); 189: BigDecimal dec = new BigDecimal(b, scale); 190: 191: return dec; 192: } 193: }