com.univocity.parsers.fixed.FixedWidthParserSettings Maven / Gradle / Ivy
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/*******************************************************************************
* Copyright 2014 Univocity Software Pty Ltd
*
* 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
*
* 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 com.univocity.parsers.fixed;
import com.univocity.parsers.annotations.*;
import com.univocity.parsers.annotations.helpers.*;
import com.univocity.parsers.common.*;
import com.univocity.parsers.common.input.*;
import java.util.*;
/**
* This is the configuration class used by the Fixed-Width parser ({@link FixedWidthParser})
*
* In addition to the configuration options provided by {@link CommonParserSettings}, the FixedWidthParserSettings include:
*
*
* - skipTrailingCharsUntilNewline (defaults to false): Indicates whether or not any trailing characters beyond the record's length should be skipped until the newline is reached
*
For example, if the record length is 5, but the row contains "12345678\n", then portion containing "678" will be discarded and not considered part of the next record
* - recordEndsOnNewline (defaults to false): Indicates whether or not a record is considered parsed when a newline is reached.
*
For example, if recordEndsOnNewline is set to true, then given a record of length 4, and the input "12\n3456", the parser will identify [12] and [3456]
*
If recordEndsOnNewline is set to false, then given a record of length 4, and the input "12\n3456", the parser will identify a multi-line record [12\n3] and [456 ]
*
*
* The FixedWidthParserSettings need a definition of the field lengths of each record in the input. This must provided using an instance of {@link FixedWidthFields}.
*
* @author Univocity Software Pty Ltd - [email protected]
* @see com.univocity.parsers.fixed.FixedWidthParser
* @see com.univocity.parsers.fixed.FixedWidthFormat
* @see FixedWidthFields
* @see com.univocity.parsers.common.CommonParserSettings
*/
public class FixedWidthParserSettings extends CommonParserSettings {
protected boolean skipTrailingCharsUntilNewline = false;
protected boolean recordEndsOnNewline = false;
private boolean useDefaultPaddingForHeaders = true;
private FixedWidthFields fieldLengths;
private Map lookaheadFormats = new HashMap();
private Map lookbehindFormats = new HashMap();
/**
* You can only create an instance of this class by providing a definition of the field lengths of each record in the input.
* This must provided using an instance of {@link FixedWidthFields}.
*
* @param fieldLengths the instance of {@link FixedWidthFields} which provides the lengths of each field in the fixed-width records to be parsed
*
* @see FixedWidthFields
*/
public FixedWidthParserSettings(FixedWidthFields fieldLengths) {
if (fieldLengths == null) {
throw new IllegalArgumentException("Field lengths cannot be null");
}
this.fieldLengths = fieldLengths;
String[] names = fieldLengths.getFieldNames();
if (names != null) {
setHeaders(names);
}
}
/**
* Creates a basic configuration object for the Fixed-Width parser with no field length configuration.
* This constructor is intended to be used when the record length varies depending of the input row.
* Refer to {@link #addFormatForLookahead(String, FixedWidthFields)}, {@link #addFormatForLookbehind(String, FixedWidthFields)}
*/
public FixedWidthParserSettings() {
fieldLengths = null;
}
/**
* Returns the sequence of lengths to be read by the parser to form a record.
*
* @return the sequence of lengths to be read by the parser to form a record.
*/
int[] getFieldLengths() {
if (fieldLengths == null) {
return null;
}
return fieldLengths.getFieldLengths();
}
int[] getAllLengths() {
if (fieldLengths == null) {
return null;
}
return fieldLengths.getAllLengths();
}
/**
* Returns the sequence of paddings used by each field of each record.
*
* @return the sequence of paddings used by each field of each record.
*/
char[] getFieldPaddings() {
if (fieldLengths == null) {
return null;
}
return fieldLengths.getFieldPaddings(this.getFormat());
}
/**
* Returns the sequence of fields to ignore.
*
* @return the sequence of fields to ignore.
*/
boolean[] getFieldsToIgnore() {
if (fieldLengths == null) {
return null;
}
return fieldLengths.getFieldsToIgnore();
}
/**
* Returns the sequence of alignments to consider for each field of each record.
*
* @return the sequence of alignments to consider for each field of each record.
*/
FieldAlignment[] getFieldAlignments() {
if (fieldLengths == null) {
return null;
}
return fieldLengths.getFieldAlignments();
}
/**
* Indicates whether or not any trailing characters beyond the record's length should be skipped until the newline is reached (defaults to false)
*
For example, if the record length is 5, but the row contains "12345678\n", then the portion containing "678\n" will be discarded and not considered part of the next record
*
* @return returns true if any trailing characters beyond the record's length should be skipped until the newline is reached, false otherwise
*/
public boolean getSkipTrailingCharsUntilNewline() {
return skipTrailingCharsUntilNewline;
}
/**
* Defines whether or not any trailing characters beyond the record's length should be skipped until the newline is reached (defaults to false)
*
For example, if the record length is 5, but the row contains "12345678\n", then the portion containing "678\n" will be discarded and not considered part of the next record
*
* @param skipTrailingCharsUntilNewline a flag indicating if any trailing characters beyond the record's length should be skipped until the newline is reached
*/
public void setSkipTrailingCharsUntilNewline(boolean skipTrailingCharsUntilNewline) {
this.skipTrailingCharsUntilNewline = skipTrailingCharsUntilNewline;
}
/**
* Indicates whether or not a record is considered parsed when a newline is reached. Examples:
*
* - Consider two records of length 4, and the input 12\n3456
* - When {@link FixedWidthParserSettings#recordEndsOnNewline} is set to true: the first value will be read as 12 and the second 3456
* - When {@link FixedWidthParserSettings#recordEndsOnNewline} is set to false: the first value will be read as 12\n3 and the second 456
*
* Defaults to false
*
* @return true if a record should be considered parsed when a newline is reached; false otherwise
*/
public boolean getRecordEndsOnNewline() {
return recordEndsOnNewline;
}
/**
* Defines whether or not a record is considered parsed when a newline is reached. Examples:
*
* - Consider two records of length 4, and the input 12\n3456
* - When {@link FixedWidthParserSettings#recordEndsOnNewline} is set to true: the first value will be read as 12 and the second 3456
* - When {@link FixedWidthParserSettings#recordEndsOnNewline} is set to false: the first value will be read as 12\n3 and the second 456
*
*
* @param recordEndsOnNewline a flag indicating whether or not a record is considered parsed when a newline is reached
*/
public void setRecordEndsOnNewline(boolean recordEndsOnNewline) {
this.recordEndsOnNewline = recordEndsOnNewline;
}
/**
* Returns the default FixedWidthFormat configured to handle Fixed-Width inputs
*
* @return and instance of FixedWidthFormat configured to handle Fixed-Width inputs
*/
@Override
protected FixedWidthFormat createDefaultFormat() {
return new FixedWidthFormat();
}
/**
* Returns an instance of CharAppender with the configured limit of maximum characters per column and, default value used to represent a null value (when the String parsed from the input is empty), and the padding character to handle unwritten positions
*
* This overrides the parent implementation to create a CharAppender capable of handling padding characters that represent unwritten positions.
*
* @return an instance of CharAppender with the configured limit of maximum characters per column and, default value used to represent a null value (when the String parsed from the input is empty), and the padding character to handle unwritten positions
*/
@Override
protected CharAppender newCharAppender() {
return new DefaultCharAppender(getMaxCharsPerColumn(), getNullValue(), getWhitespaceRangeStart());
}
/**
* The maximum number of characters allowed for any given value being written/read. Used to avoid OutOfMemoryErrors (defaults to a minimum of 4096 characters).
*
*
This overrides the parent implementation and calculates the absolute minimum number of characters required to store the values of a record
*
If the sum of all field lengths is greater than the configured maximum number of characters per column, the calculated amount will be returned.
*
* @return The maximum number of characters allowed for any given value being written/read
*/
@Override
public int getMaxCharsPerColumn() {
int max = super.getMaxCharsPerColumn();
int minimum = 0;
for (int length : calculateMaxFieldLengths()) {
//adding 2 to give room for line breaks in every record (e.g. "\r\n").
minimum += length + 2;
}
return max > minimum ? max : minimum;
}
/**
* Returns the hard limit of how many columns a record can have (defaults to a maximum of 512).
* You need this to avoid OutOfMemory errors in case of inputs that might be inconsistent with the format you are dealing with.
*
*
This overrides the parent implementation and calculates the absolute minimum number of columns required to store the values of a record
*
If the sum of all fields is greater than the configured maximum number columns, the calculated amount will be returned.
*
* @return The maximum number of columns a record can have.
*/
@Override
public int getMaxColumns() {
int max = super.getMaxColumns();
int minimum = calculateMaxFieldLengths().length;
return max > minimum ? max : minimum;
}
private int[] calculateMaxFieldLengths() {
return Lookup.calculateMaxFieldLengths(fieldLengths, lookaheadFormats, lookbehindFormats);
}
Lookup[] getLookaheadFormats() {
return Lookup.getLookupFormats(lookaheadFormats, getFormat());
}
Lookup[] getLookbehindFormats() {
return Lookup.getLookupFormats(lookbehindFormats, getFormat());
}
/**
* Defines the format of records identified by a lookahead symbol.
*
* @param lookahead the lookahead value that when found in the input,
* will notify the parser to switch to a new record format, with different field lengths
* @param lengths the field lengths of the record format identified by the given lookahead symbol.
*/
public void addFormatForLookahead(String lookahead, FixedWidthFields lengths) {
Lookup.registerLookahead(lookahead, lengths, lookaheadFormats);
}
/**
* Defines the format of records identified by a lookbehind symbol.
*
* @param lookbehind the lookbehind value that when found in the previous input row,
* will notify the parser to switch to a new record format, with different field lengths
* @param lengths the field lengths of the record format identified by the given lookbehind symbol.
*/
public void addFormatForLookbehind(String lookbehind, FixedWidthFields lengths) {
Lookup.registerLookbehind(lookbehind, lengths, lookbehindFormats);
}
/**
* Indicates whether headers should be parsed using the default padding specified in {@link FixedWidthFormat#getPadding()}
* instead of any custom padding associated with a given field (in {@link FixedWidthFields#setPadding(char, int...)})
* Defaults to {@code true}
*
* @return {@code true} if the default padding is to be used when reading headers, otherwise {@code false}
*/
public boolean getUseDefaultPaddingForHeaders() {
return useDefaultPaddingForHeaders;
}
/**
* Defines whether headers should be parsed using the default padding specified in {@link FixedWidthFormat#getPadding()}
* instead of any custom padding associated with a given field (in {@link FixedWidthFields#setPadding(char, int...)})
*
* @param useDefaultPaddingForHeaders flag indicating whether the default padding is to be used when parsing headers
*/
public void setUseDefaultPaddingForHeaders(boolean useDefaultPaddingForHeaders) {
this.useDefaultPaddingForHeaders = useDefaultPaddingForHeaders;
}
@Override
protected void configureFromAnnotations(Class beanClass) {
if (fieldLengths == null) {
try {
fieldLengths = FixedWidthFields.forParsing(beanClass);
Headers headerAnnotation = AnnotationHelper.findHeadersAnnotation(beanClass);
if (headerExtractionEnabled == null && headerAnnotation != null) {
setHeaderExtractionEnabled(headerAnnotation.extract());
}
} catch (IllegalArgumentException e) {
throw e;
} catch (Exception ex) {
//ignore.
}
}
if (headerExtractionEnabled == null) {
setHeaderExtractionEnabled(false);
}
super.configureFromAnnotations(beanClass);
if (!isHeaderExtractionEnabled()) {
FixedWidthFields.setHeadersIfPossible(fieldLengths, this);
}
}
@Override
protected void addConfiguration(Map out) {
super.addConfiguration(out);
out.put("Skip trailing characters until new line", skipTrailingCharsUntilNewline);
out.put("Record ends on new line", recordEndsOnNewline);
out.put("Field lengths", fieldLengths == null ? "" : fieldLengths.toString());
out.put("Lookahead formats", lookaheadFormats);
out.put("Lookbehind formats", lookbehindFormats);
}
/**
* Clones this configuration object to reuse all user-provided settings, including the fixed-width field configuration.
*
* @return a copy of all configurations applied to the current instance.
*/
@Override
public final FixedWidthParserSettings clone() {
return (FixedWidthParserSettings) super.clone();
}
/**
* Clones this configuration object to reuse most user-provided settings. This includes the fixed-width field configuration,
* but doesn't include other input-specific settings. This method is meant to be used internally only.
*
* @return a copy of all configurations applied to the current instance.
*
* @deprecated doesn't really make sense for fixed-width. Use alternative method {@link #clone(FixedWidthFields)}.
*/
@Deprecated
protected final FixedWidthParserSettings clone(boolean clearInputSpecificSettings) {
return clone(clearInputSpecificSettings, fieldLengths == null ? null : fieldLengths.clone());
}
/**
* Clones this configuration object to reuse most user-provided settings. Properties that are specific to a given
* input (such as header names and selection of fields) will be reset to their defaults.
*
* To obtain a full copy, use {@link #clone()}.
*
* @param fields the fixed-width field configuration to be used by the cloned settings object.
*
* @return a copy of the general configurations applied to the current instance.
*/
public final FixedWidthParserSettings clone(FixedWidthFields fields) {
return clone(true, fields);
}
private FixedWidthParserSettings clone(boolean clearInputSpecificSettings, FixedWidthFields fields) {
FixedWidthParserSettings out = (FixedWidthParserSettings) super.clone(clearInputSpecificSettings);
out.fieldLengths = fields;
if (clearInputSpecificSettings) {
out.lookaheadFormats = new HashMap();
out.lookbehindFormats = new HashMap();
} else {
out.lookaheadFormats = new HashMap(this.lookaheadFormats);
out.lookbehindFormats = new HashMap(this.lookbehindFormats);
}
return out;
}
}