package com.marshalchen.common.uimodule.customshapeimageview.svgandroid; /* Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You 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. */ /** * Parses numbers from SVG text. Based on the Batik Number Parser (Apache 2 License). * * @author Apache Software Foundation, Larva Labs LLC */ public class ParserHelper { private char current; private CharSequence s; public int pos; private int n; public ParserHelper(CharSequence s, int pos) { this.s = s; this.pos = pos; n = s.length(); current = s.charAt(pos); } private char read() { if (pos < n) { pos++; } if (pos == n) { return '\0'; } else { return s.charAt(pos); } } public void skipWhitespace() { while (pos < n) { if (Character.isWhitespace(s.charAt(pos))) { advance(); } else { break; } } } public void skipNumberSeparator() { while (pos < n) { char c = s.charAt(pos); switch (c) { case ' ': case ',': case '\n': case '\t': advance(); break; default: return; } } } public void advance() { current = read(); } /** * Parses the content of the buffer and converts it to a float. */ public float parseFloat() { int mant = 0; int mantDig = 0; boolean mantPos = true; boolean mantRead = false; int exp = 0; int expDig = 0; int expAdj = 0; boolean expPos = true; switch (current) { case '-': mantPos = false; // fallthrough case '+': current = read(); } m1: switch (current) { default: return Float.NaN; case '.': break; case '0': mantRead = true; l: for (;;) { current = read(); switch (current) { case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': break l; case '.': case 'e': case 'E': break m1; default: return 0.0f; case '0': } } case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': mantRead = true; l: for (;;) { if (mantDig < 9) { mantDig++; mant = mant * 10 + (current - '0'); } else { expAdj++; } current = read(); switch (current) { default: break l; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': } } } if (current == '.') { current = read(); m2: switch (current) { default: case 'e': case 'E': if (!mantRead) { reportUnexpectedCharacterError( current ); return 0.0f; } break; case '0': if (mantDig == 0) { l: for (;;) { current = read(); expAdj--; switch (current) { case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': break l; default: if (!mantRead) { return 0.0f; } break m2; case '0': } } } case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': l: for (;;) { if (mantDig < 9) { mantDig++; mant = mant * 10 + (current - '0'); expAdj--; } current = read(); switch (current) { default: break l; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': } } } } switch (current) { case 'e': case 'E': current = read(); switch (current) { default: reportUnexpectedCharacterError( current ); return 0f; case '-': expPos = false; case '+': current = read(); switch (current) { default: reportUnexpectedCharacterError( current ); return 0f; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': } case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': } en: switch (current) { case '0': l: for (;;) { current = read(); switch (current) { case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': break l; default: break en; case '0': } } case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': l: for (;;) { if (expDig < 3) { expDig++; exp = exp * 10 + (current - '0'); } current = read(); switch (current) { default: break l; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': } } } default: } if (!expPos) { exp = -exp; } exp += expAdj; if (!mantPos) { mant = -mant; } return buildFloat(mant, exp); } private void reportUnexpectedCharacterError(char c) { throw new RuntimeException("Unexpected char '" + c + "'."); } /** * Computes a float from mantissa and exponent. */ public static float buildFloat(int mant, int exp) { if (exp < -125 || mant == 0) { return 0.0f; } if (exp >= 128) { return (mant > 0) ? Float.POSITIVE_INFINITY : Float.NEGATIVE_INFINITY; } if (exp == 0) { return mant; } if (mant >= (1 << 26)) { mant++; // round up trailing bits if they will be dropped. } return (float) ((exp > 0) ? mant * pow10[exp] : mant / pow10[-exp]); } /** * Array of powers of ten. Using double instead of float gives a tiny bit more precision. */ private static final double[] pow10 = new double[128]; static { for (int i = 0; i < pow10.length; i++) { pow10[i] = Math.pow(10, i); } } public float nextFloat() { skipWhitespace(); float f = parseFloat(); skipNumberSeparator(); return f; } }