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.text.DateFormat; import java.text.DecimalFormat; import java.text.NumberFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Arrays; import java.util.Date; import java.util.List; import java.util.Locale; import java.util.Properties; import org.springframework.util.Assert; import org.springframework.util.StringUtils; /** * Default implementation of {@link FieldSet} using Java using Java primitive * and standard types and utilities. Strings are trimmed before parsing by * default, and so are plain String values. * * @author Rob Harrop * @author Dave Syer */ public class DefaultFieldSet implements FieldSet { private final static String DEFAULT_DATE_PATTERN = "yyyy-MM-dd"; private DateFormat dateFormat = new SimpleDateFormat(DEFAULT_DATE_PATTERN); { dateFormat.setLenient(false); } private NumberFormat numberFormat = NumberFormat.getInstance(Locale.US); private String grouping = ","; private String decimal = "."; /** * The fields wrapped by this '<code>FieldSet</code>' instance. */ private String[] tokens; private List<String> names; /** * The {@link NumberFormat} to use for parsing numbers. If unset the US * locale will be used ('.' as decimal place). * @param numberFormat the {@link NumberFormat} to use for number parsing */ public final void setNumberFormat(NumberFormat numberFormat) { this.numberFormat = numberFormat; if (numberFormat instanceof DecimalFormat) { grouping = "" + ((DecimalFormat) numberFormat).getDecimalFormatSymbols().getGroupingSeparator(); decimal = "" + ((DecimalFormat) numberFormat).getDecimalFormatSymbols().getDecimalSeparator(); } } /** * The {@link DateFormat} to use for parsing numbers. If unset the default * pattern is ISO standard <code>yyyy/MM/dd</code>. * @param dateFormat the {@link DateFormat} to use for date parsing */ public void setDateFormat(DateFormat dateFormat) { this.dateFormat = dateFormat; } /** * Create a FieldSet with anonymous tokens. They can only be retrieved by * column number. * @param tokens the token values * @see FieldSet#readString(int) */ public DefaultFieldSet(String[] tokens) { this.tokens = tokens == null ? null : tokens.clone(); setNumberFormat(NumberFormat.getInstance(Locale.US)); } /** * Create a FieldSet with named tokens. The token values can then be * retrieved either by name or by column number. * @param tokens the token values * @param names the names of the tokens * @see FieldSet#readString(String) */ public DefaultFieldSet(String[] tokens, String[] names) { Assert.notNull(tokens, "Tokens must not be null"); Assert.notNull(names, "Names must not be null"); if (tokens.length != names.length) { throw new IllegalArgumentException("Field names must be same length as values: names=" + Arrays.asList(names) + ", values=" + Arrays.asList(tokens)); } this.tokens = tokens.clone(); this.names = Arrays.asList(names); setNumberFormat(NumberFormat.getInstance(Locale.US)); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#getNames() */ @Override public String[] getNames() { if (names == null) { throw new IllegalStateException("Field names are not known"); } return names.toArray(new String[names.size()]); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.FieldSet#hasNames() */ @Override public boolean hasNames() { return names != null; } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#getValues() */ @Override public String[] getValues() { return tokens.clone(); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readString(int) */ @Override public String readString(int index) { return readAndTrim(index); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readString(java * .lang.String) */ @Override public String readString(String name) { return readString(indexOf(name)); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readRawString(int) */ @Override public String readRawString(int index) { return tokens[index]; } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readRawString(java * .lang.String) */ @Override public String readRawString(String name) { return readRawString(indexOf(name)); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readBoolean(int) */ @Override public boolean readBoolean(int index) { return readBoolean(index, "true"); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readBoolean(java * .lang.String) */ @Override public boolean readBoolean(String name) { return readBoolean(indexOf(name)); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readBoolean(int, * java.lang.String) */ @Override public boolean readBoolean(int index, String trueValue) { Assert.notNull(trueValue, "'trueValue' cannot be null."); String value = readAndTrim(index); return trueValue.equals(value); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readBoolean(java * .lang.String, java.lang.String) */ @Override public boolean readBoolean(String name, String trueValue) { return readBoolean(indexOf(name), trueValue); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readChar(int) */ @Override public char readChar(int index) { String value = readAndTrim(index); Assert.isTrue(value.length() == 1, "Cannot convert field value '" + value + "' to char."); return value.charAt(0); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readChar(java.lang * .String) */ @Override public char readChar(String name) { return readChar(indexOf(name)); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readByte(int) */ @Override public byte readByte(int index) { return Byte.parseByte(readAndTrim(index)); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readByte(java.lang * .String) */ @Override public byte readByte(String name) { return readByte(indexOf(name)); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readShort(int) */ @Override public short readShort(int index) { return Short.parseShort(readAndTrim(index)); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readShort(java. * lang.String) */ @Override public short readShort(String name) { return readShort(indexOf(name)); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readInt(int) */ @Override public int readInt(int index) { return parseNumber(readAndTrim(index)).intValue(); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readInt(java.lang * .String) */ @Override public int readInt(String name) { return readInt(indexOf(name)); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readInt(int, * int) */ @Override public int readInt(int index, int defaultValue) { String value = readAndTrim(index); return StringUtils.hasLength(value) ? Integer.parseInt(value) : defaultValue; } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readInt(java.lang * .String, int) */ @Override public int readInt(String name, int defaultValue) { return readInt(indexOf(name), defaultValue); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readLong(int) */ @Override public long readLong(int index) { return parseNumber(readAndTrim(index)).longValue(); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readLong(java.lang * .String) */ @Override public long readLong(String name) { return readLong(indexOf(name)); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readLong(int, * long) */ @Override public long readLong(int index, long defaultValue) { String value = readAndTrim(index); return StringUtils.hasLength(value) ? Long.parseLong(value) : defaultValue; } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readLong(java.lang * .String, long) */ @Override public long readLong(String name, long defaultValue) { return readLong(indexOf(name), defaultValue); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readFloat(int) */ @Override public float readFloat(int index) { return parseNumber(readAndTrim(index)).floatValue(); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readFloat(java. * lang.String) */ @Override public float readFloat(String name) { return readFloat(indexOf(name)); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readDouble(int) */ @Override public double readDouble(int index) { return parseNumber(readAndTrim(index)).doubleValue(); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readDouble(java * .lang.String) */ @Override public double readDouble(String name) { return readDouble(indexOf(name)); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readBigDecimal(int) */ @Override public BigDecimal readBigDecimal(int index) { return readBigDecimal(index, null); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readBigDecimal( * java.lang.String) */ @Override public BigDecimal readBigDecimal(String name) { return readBigDecimal(name, null); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readBigDecimal(int, * java.math.BigDecimal) */ @Override public BigDecimal readBigDecimal(int index, BigDecimal defaultValue) { String candidate = readAndTrim(index); if (!StringUtils.hasText(candidate)) { return defaultValue; } try { String result = removeSeparators(candidate); return new BigDecimal(result); } catch (NumberFormatException e) { throw new NumberFormatException("Unparseable number: " + candidate); } } private String removeSeparators(String candidate) { return candidate.replace(grouping, "").replace(decimal, "."); } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readBigDecimal( * java.lang.String, java.math.BigDecimal) */ @Override public BigDecimal readBigDecimal(String name, BigDecimal defaultValue) { try { return readBigDecimal(indexOf(name), defaultValue); } catch (NumberFormatException e) { throw new NumberFormatException(e.getMessage() + ", name: [" + name + "]"); } catch (IllegalArgumentException e) { throw new IllegalArgumentException(e.getMessage() + ", name: [" + name + "]"); } } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readDate(int) */ @Override public Date readDate(int index) { return parseDate(readAndTrim(index), dateFormat); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.transform.FieldSet#readDate(int, * java.util.Date) */ @Override public Date readDate(int index, Date defaultValue) { String candidate = readAndTrim(index); return StringUtils.hasText(candidate) ? parseDate(candidate, dateFormat) : defaultValue; } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readDate(java.lang * .String) */ @Override public Date readDate(String name) { try { return readDate(indexOf(name)); } catch (IllegalArgumentException e) { throw new IllegalArgumentException(e.getMessage() + ", name: [" + name + "]"); } } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.transform.FieldSet#readDate(int, * java.util.Date) */ @Override public Date readDate(String name, Date defaultValue) { try { return readDate(indexOf(name), defaultValue); } catch (IllegalArgumentException e) { throw new IllegalArgumentException(e.getMessage() + ", name: [" + name + "]"); } } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readDate(int, * java.lang.String) */ @Override public Date readDate(int index, String pattern) { SimpleDateFormat sdf = new SimpleDateFormat(pattern); sdf.setLenient(false); return parseDate(readAndTrim(index), sdf); } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readDate(int, * java.lang.String) */ @Override public Date readDate(int index, String pattern, Date defaultValue) { String candidate = readAndTrim(index); return StringUtils.hasText(candidate) ? readDate(index, pattern) : defaultValue; } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#readDate(java.lang * .String, java.lang.String) */ @Override public Date readDate(String name, String pattern) { try { return readDate(indexOf(name), pattern); } catch (IllegalArgumentException e) { throw new IllegalArgumentException(e.getMessage() + ", name: [" + name + "]"); } } /* * (non-Javadoc) * * @see org.springframework.batch.item.file.mapping.IFieldSet#readDate(int, * java.lang.String) */ @Override public Date readDate(String name, String pattern, Date defaultValue) { try { return readDate(indexOf(name), pattern, defaultValue); } catch (IllegalArgumentException e) { throw new IllegalArgumentException(e.getMessage() + ", name: [" + name + "]"); } } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#getFieldCount() */ @Override public int getFieldCount() { return tokens.length; } /** * Read and trim the {@link String} value at '<code>index</code>'. * * @param index the offset in the token array to obtain the value to be trimmed. * * @return null if the field value is <code>null</code>. */ protected String readAndTrim(int index) { String value = tokens[index]; if (value != null) { return value.trim(); } else { return null; } } /** * Retrieve the index of where a specified column is located based on the * {@code name} parameter. * * @param name the value to search in the {@link List} of names. * @return the index in the {@link List} of names where the name was found. * * @throws IllegalArgumentException if a column with given name is not * defined. */ protected int indexOf(String name) { if (names == null) { throw new IllegalArgumentException("Cannot access columns by name without meta data"); } int index = names.indexOf(name); if (index >= 0) { return index; } throw new IllegalArgumentException("Cannot access column [" + name + "] from " + names); } @Override public String toString() { if (names != null) { return getProperties().toString(); } return tokens == null ? "" : Arrays.asList(tokens).toString(); } /** * @see java.lang.Object#equals(java.lang.Object) */ @Override public boolean equals(Object object) { if (object instanceof DefaultFieldSet) { DefaultFieldSet fs = (DefaultFieldSet) object; if (this.tokens == null) { return fs.tokens == null; } else { return Arrays.equals(this.tokens, fs.tokens); } } return false; } @Override public int hashCode() { // this algorithm was taken from java 1.5 jdk Arrays.hashCode(Object[]) if (tokens == null) { return 0; } int result = 1; for (String token : tokens) { result = 31 * result + (token == null ? 0 : token.hashCode()); } return result; } /* * (non-Javadoc) * * @see * org.springframework.batch.item.file.mapping.IFieldSet#getProperties() */ @Override public Properties getProperties() { if (names == null) { throw new IllegalStateException("Cannot create properties without meta data"); } Properties props = new Properties(); for (int i = 0; i < tokens.length; i++) { String value = readAndTrim(i); if (value != null) { props.setProperty(names.get(i), value); } } return props; } private Number parseNumber(String candidate) { try { return numberFormat.parse(candidate); } catch (ParseException e) { throw new NumberFormatException("Unparseable number: " + candidate); } } private Date parseDate(String readAndTrim, DateFormat dateFormat) { try { return dateFormat.parse(readAndTrim); } catch (ParseException e) { String pattern; if (dateFormat instanceof SimpleDateFormat) { pattern = ((SimpleDateFormat) dateFormat).toPattern(); } else { pattern = dateFormat.toString(); } throw new IllegalArgumentException(e.getMessage() + ", format: [" + pattern + "]"); } } }