Java tutorial
/* * Copyright 2006-2007 the original author or authors. * * Licensed 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 * * https://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.springframework.batch.item.file.transform; import java.math.BigDecimal; import java.sql.ResultSet; import java.util.Date; import java.util.Properties; /** * Interface used by flat file input sources to encapsulate concerns of * converting an array of Strings to Java native types. A bit like the role * played by {@link ResultSet} in JDBC, clients will know the name or position * of strongly typed fields that they want to extract. * * @author Dave Syer * */ public interface FieldSet { /** * Accessor for the names of the fields. * * @return the names * * @throws IllegalStateException if the names are not defined */ String[] getNames(); /** * Check if there are names defined for the fields. * * @return true if there are names for the fields */ boolean hasNames(); /** * @return fields wrapped by this '<code>FieldSet</code>' instance as * String values. */ String[] getValues(); /** * Read the {@link String} value at index '<code>index</code>'. * * @param index the field index. * @return {@link String} containing the value at the index. * * @throws IndexOutOfBoundsException if the {@code index} is out of bounds. */ String readString(int index); /** * Read the {@link String} value from column with given '<code>name</code>'. * * @param name the field {@code name}. * @return {@link String} containing the value from the specified {@code name}. */ String readString(String name); /** * Read the {@link String} value at index '<code>index</code>' including * trailing whitespace (don't trim). * * @param index the field index. * @return {@link String} containing the value from the specified {@code index}. * * @throws IndexOutOfBoundsException if the {@code index} is out of bounds. */ String readRawString(int index); /** * Read the {@link String} value from column with given '<code>name</code>' * including trailing whitespace (don't trim). * * @param name the field {@code name}. * @return {@link String} containing the value from the specified {@code name}. */ String readRawString(String name); /** * Read the '<code>boolean</code>' value at index '<code>index</code>'. * * @param index the field index. * @return boolean containing the value from the specified {@code index}. * * @throws IndexOutOfBoundsException if the {@code index} is out of bounds. */ boolean readBoolean(int index); /** * Read the '<code>boolean</code>' value from column with given '<code>name</code>'. * * @param name the field {@code name}. * @return boolean containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ boolean readBoolean(String name); /** * Read the '<code>boolean</code>' value at index '<code>index</code>'. * * @param index the field index. * @param trueValue the value that signifies {@link Boolean#TRUE true}; * case-sensitive. * @return boolean containing the value from the specified {@code index}. * * @throws IndexOutOfBoundsException if the index is out of bounds, or if * the supplied <code>trueValue</code> is <code>null</code>. */ boolean readBoolean(int index, String trueValue); /** * Read the '<code>boolean</code>' value from column with given '<code>name</code>'. * * @param name the field {@code name}. * @param trueValue the value that signifies {@link Boolean#TRUE true}; * case-sensitive. * @return boolean containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined, or if the supplied <code>trueValue</code> is <code>null</code>. */ boolean readBoolean(String name, String trueValue); /** * Read the '<code>char</code>' value at index '<code>index</code>'. * * @param index the field index. * @return char containing the value from the specified {@code index}. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ char readChar(int index); /** * Read the '<code>char</code>' value from column with given '<code>name</code>'. * * @param name the field {@code name}. * @return char containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ char readChar(String name); /** * Read the '<code>byte</code>' value at index '<code>index</code>'. * * @param index the field index. * @return byte containing the value from the specified {@code index}. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ byte readByte(int index); /** * Read the '<code>byte</code>' value from column with given '<code>name</code>'. * * @param name the field {@code name}. * @return byte containing the value from the specified {@code name}. */ byte readByte(String name); /** * Read the '<code>short</code>' value at index '<code>index</code>'. * * @param index the field {@code index}. * @return short containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ short readShort(int index); /** * Read the '<code>short</code>' value from column with given '<code>name</code>'. * * @param name the field {@code name}. * @return short containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ short readShort(String name); /** * Read the '<code>int</code>' value at index '<code>index</code>'. * * @param index the field index. * @return int containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ int readInt(int index); /** * Read the '<code>int</code>' value from column with given '<code>name</code>'. * * @param name the field {@code name}. * @return int containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ int readInt(String name); /** * Read the '<code>int</code>' value at index '<code>index</code>', * using the supplied <code>defaultValue</code> if the field value is * blank. * * @param index the field index. * @param defaultValue the value to use if the field value is blank. * @return int containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ int readInt(int index, int defaultValue); /** * Read the '<code>int</code>' value from column with given '<code>name</code>', * using the supplied <code>defaultValue</code> if the field value is * blank. * * @param name the field {@code name}. * @param defaultValue the value to use if the field value is blank. * @return int containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ int readInt(String name, int defaultValue); /** * Read the '<code>long</code>' value at index '<code>index</code>'. * * @param index the field index. * @return long containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ long readLong(int index); /** * Read the '<code>long</code>' value from column with given '<code>name</code>'. * * @param name the field {@code name}. * @return long containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ long readLong(String name); /** * Read the '<code>long</code>' value at index '<code>index</code>', * using the supplied <code>defaultValue</code> if the field value is * blank. * * @param index the field index. * @param defaultValue the value to use if the field value is blank. * @return long containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ long readLong(int index, long defaultValue); /** * Read the '<code>long</code>' value from column with given '<code>name</code>', * using the supplied <code>defaultValue</code> if the field value is * blank. * * @param name the field {@code name}. * @param defaultValue the value to use if the field value is blank. * @return long containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ long readLong(String name, long defaultValue); /** * Read the '<code>float</code>' value at index '<code>index</code>'. * * @param index the field index. * @return float containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ float readFloat(int index); /** * Read the '<code>float</code>' value from column with given '<code>name</code>. * * @param name the field {@code name}. * @return float containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ float readFloat(String name); /** * Read the '<code>double</code>' value at index '<code>index</code>'. * * @param index the field index. * @return double containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ double readDouble(int index); /** * Read the '<code>double</code>' value from column with given '<code>name</code>. * * @param name the field {@code name}. * @return double containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ double readDouble(String name); /** * Read the {@link java.math.BigDecimal} value at index '<code>index</code>'. * * @param index the field index. * @return {@link BigDecimal} containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ BigDecimal readBigDecimal(int index); /** * Read the {@link java.math.BigDecimal} value from column with given '<code>name</code>. * * @param name the field {@code name}. * @return {@link BigDecimal} containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ BigDecimal readBigDecimal(String name); /** * Read the {@link BigDecimal} value at index '<code>index</code>', * returning the supplied <code>defaultValue</code> if the trimmed string * value at index '<code>index</code>' is blank. * * @param index the field index. * @param defaultValue the value to use if the field value is blank. * @return {@link BigDecimal} containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. */ BigDecimal readBigDecimal(int index, BigDecimal defaultValue); /** * Read the {@link BigDecimal} value from column with given '<code>name</code>, * returning the supplied <code>defaultValue</code> if the trimmed string * value at index '<code>index</code>' is blank. * * @param name the field {@code name}. * @param defaultValue the default value to use if the field is blank * @return {@link BigDecimal} containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ BigDecimal readBigDecimal(String name, BigDecimal defaultValue); /** * Read the <code>java.util.Date</code> value in default format at * designated column <code>index</code>. * * @param index the field index. * @return {@link Date} containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. * @throws IllegalArgumentException if the value is not parseable * @throws NullPointerException if the value is empty */ Date readDate(int index); /** * Read the <code>java.sql.Date</code> value in given format from column * with given <code>name</code>. * * @param name the field {@code name}. * @return {@link Date} containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined or if the value is not parseable * @throws NullPointerException if the value is empty */ Date readDate(String name); /** * Read the <code>java.util.Date</code> value in default format at * designated column <code>index</code>. * * @param index the field index. * @param defaultValue the default value to use if the field is blank * @return {@link Date} containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. * @throws IllegalArgumentException if the value is not parseable * @throws NullPointerException if the value is empty */ Date readDate(int index, Date defaultValue); /** * Read the <code>java.sql.Date</code> value in given format from column * with given <code>name</code>. * * @param name the field {@code name}. * @param defaultValue the default value to use if the field is blank * @return {@link Date} containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined. */ Date readDate(String name, Date defaultValue); /** * Read the <code>java.util.Date</code> value in default format at * designated column <code>index</code>. * * @param index the field index. * @param pattern the pattern describing the date and time format * @return {@link Date} containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. * @throws IllegalArgumentException if the date cannot be parsed. * */ Date readDate(int index, String pattern); /** * Read the <code>java.sql.Date</code> value in given format from column * with given <code>name</code>. * * @param name the field {@code name}. * @param pattern the pattern describing the date and time format * @return {@link Date} containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined or if the specified field cannot be parsed * */ Date readDate(String name, String pattern); /** * Read the <code>java.util.Date</code> value in default format at * designated column <code>index</code>. * * @param index the field index. * @param pattern the pattern describing the date and time format * @param defaultValue the default value to use if the field is blank * @return {@link Date} containing the value from the specified index. * * @throws IndexOutOfBoundsException if the index is out of bounds. * @throws IllegalArgumentException if the date cannot be parsed. * */ Date readDate(int index, String pattern, Date defaultValue); /** * Read the <code>java.sql.Date</code> value in given format from column * with given <code>name</code>. * * @param name the field {@code name}. * @param pattern the pattern describing the date and time format * @param defaultValue the default value to use if the field is blank * @return {@link Date} containing the value from the specified {@code name}. * * @throws IllegalArgumentException if a column with given {@code name} is not * defined or if the specified field cannot be parsed * */ Date readDate(String name, String pattern, Date defaultValue); /** * Return the number of fields in this '<code>FieldSet</code>'. * * @return int containing the number of fields in this field set. */ int getFieldCount(); /** * Construct name-value pairs from the field names and string values. Null * values are omitted. * * @return some properties representing the field set. * * @throws IllegalStateException if the field name meta data is not * available. */ Properties getProperties(); }