content: /*
   * 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.
   */
  package org.apache.calcite.sql;
  
  import org.apache.calcite.rel.type.RelDataType;
  import org.apache.calcite.rel.type.RelDataTypeFactory;
  import org.apache.calcite.sql.parser.SqlParserPos;
  import org.apache.calcite.sql.type.SqlTypeName;
  import org.apache.calcite.util.Util;
  
  import org.checkerframework.checker.nullness.qual.Nullable;
  import org.checkerframework.dataflow.qual.Pure;
  
  import java.math.BigDecimal;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * A numeric SQL literal.
   */
  public class SqlNumericLiteral extends SqlLiteral {
    //~ Instance fields --------------------------------------------------------
  
    private final @Nullable Integer prec;
    private final @Nullable Integer scale;
    private final boolean exact;
  
    //~ Constructors -----------------------------------------------------------
  
    protected SqlNumericLiteral(
        BigDecimal value,
        @Nullable Integer prec,
        @Nullable Integer scale,
        boolean exact,
        SqlParserPos pos) {
      super(
          value,
          exact ? SqlTypeName.DECIMAL : SqlTypeName.DOUBLE,
          pos);
      this.prec = prec;
      this.scale = scale;
      this.exact = exact;
    }
  
    //~ Methods ----------------------------------------------------------------
  
    private BigDecimal getValueNonNull() {
      return (BigDecimal) requireNonNull(value, "value");
    }
  
    public @Nullable Integer getPrec() {
      return prec;
    }
  
    @Pure
    public @Nullable Integer getScale() {
      return scale;
    }
  
    public boolean isExact() {
      return exact;
    }
  
    @Override public SqlNumericLiteral clone(SqlParserPos pos) {
      return new SqlNumericLiteral(getValueNonNull(), getPrec(), getScale(),
          exact, pos);
    }
  
    @Override public void unparse(
        SqlWriter writer,
        int leftPrec,
        int rightPrec) {
      writer.getDialect().unparseNumericLiteral(writer, toValue(), leftPrec, rightPrec);
    }
  
    @Override public String toValue() {
      final BigDecimal bd = getValueNonNull();
      if (exact) {
        return bd.toPlainString();
      }
      return Util.toScientificNotation(bd);
    }
  
    @Override public RelDataType createSqlType(RelDataTypeFactory typeFactory) {
      if (exact) {
        int scaleValue = requireNonNull(scale, "scale");
        if (0 == scaleValue) {
          try {
            BigDecimal bd = getValueNonNull();
            SqlTypeName result;
            // Will throw if the number cannot be represented as a long.
            long l = bd.longValueExact();
            if ((l >= Integer.MIN_VALUE) && (l <= Integer.MAX_VALUE)) {
              result = SqlTypeName.INTEGER;
            } else {
              result = SqlTypeName.BIGINT;
            }
            return typeFactory.createSqlType(result);
          } catch (ArithmeticException ex) {
            // This indicates that the value does not fit in any integer type.
            // Fallback to DECIMAL.
          }
        }
        // else we have a decimal
        return typeFactory.createSqlType(
            SqlTypeName.DECIMAL,
            requireNonNull(prec, "prec"),
            scaleValue);
      }
  
      // else we have a FLOAT, REAL or DOUBLE.  make them all DOUBLE for
      // now.
      return typeFactory.createSqlType(SqlTypeName.DOUBLE);
    }
  
    public boolean isInteger() {
      return scale != null && 0 == scale.intValue();
    }
  }
  