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/*
* Copyright 2007 Kasper B. Graversen
*
* 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 org.supercsv.prefs;
/**
* Before reading or writing CSV files, you must supply the reader/writer with some preferences.
*
* Please note: the end of line symbols are only used for writing.
*
* The following predefined configurations are available:
*
*
*
* Constant
* Quote character
* Delimiter character
* End of line symbols
*
*
* STANDARD_PREFERENCE",\r\n
*
* EXCEL_PREFERENCE",\n
*
* EXCEL_NORTH_EUROPE_PREFERENCE";\n
*
* TAB_PREFERENCE"\t\n
*
*
*
* By default, spaces surrounding an unquoted cell are treated as part of the data. In versions of Super CSV prior to
* 2.0.0 this wasn't the case, and any surrounding spaces that weren't within quotes were ignored when reading (and
* quotes were automatically added to Strings containing surrounding spaces when writing).
*
* If you wish enable this functionality again, then you can create a CsvPreference with the
* surroundingSpacesNeedQuotes flag set to true (the default is false). This means that surrounding spaces without
* quotes will be trimmed when reading, and quotes will automatically be added for Strings containing surrounding spaces
* when writing.
*
* You can apply the surroundingSpacesNeedQuotes property to an existing preference as follows:
* {@code private static final CsvPreference STANDARD_SURROUNDING_SPACES_NEED_QUOTES = new CsvPreference.Builder(CsvPreference.STANDARD_PREFERENCE).surroundingSpacesNeedQuotes(true).build();}
*
* You can also create your own preferences. For example if your file was pipe-delimited, you could use the following:
* {@code private static final CsvPreference PIPE_DELIMITED = new CsvPreference.Builder('"', '|', "\n").build();}
*
* @author Kasper B. Graversen
* @author James Bassett
*/
public final class CsvPreference {
/**
* Ready to use configuration that should cover 99% of all usages.
*/
public static final CsvPreference STANDARD_PREFERENCE = new CsvPreference.Builder('"', ',', "\r\n").build();
/**
* Ready to use configuration for Windows Excel exported CSV files.
*/
public static final CsvPreference EXCEL_PREFERENCE = new CsvPreference.Builder('"', ',', "\n").build();
/**
* Ready to use configuration for north European excel CSV files (columns are separated by ";" instead of ",")
*/
public static final CsvPreference EXCEL_NORTH_EUROPE_PREFERENCE = new CsvPreference.Builder('"', ';', "\n").build();
/**
* Ready to use configuration for tab-delimited files.
*/
public static final CsvPreference TAB_PREFERENCE = new CsvPreference.Builder('"', '\t', "\n").build();
private final char quoteChar;
private final int delimiterChar;
private final String endOfLineSymbols;
private final boolean surroundingSpacesNeedQuotes;
/**
* Constructs a new CsvPreference from a Builder.
*/
private CsvPreference(Builder builder) {
this.quoteChar = builder.quoteChar;
this.delimiterChar = builder.delimiterChar;
this.endOfLineSymbols = builder.endOfLineSymbols;
this.surroundingSpacesNeedQuotes = builder.surroundingSpacesNeedQuotes;
}
/**
* Returns the delimiter character
*
* @return the delimiter character
*/
public int getDelimiterChar() {
return delimiterChar;
}
/**
* Returns the end of line symbols
*
* @return the end of line symbols
*/
public String getEndOfLineSymbols() {
return endOfLineSymbols;
}
/**
* Returns the quote character
*
* @return the quote character
*/
public int getQuoteChar() {
return quoteChar;
}
/**
* Returns the surroundingSpacesNeedQuotes flag.
*
* @return the surroundingSpacesNeedQuotes flag
*/
public boolean isSurroundingSpacesNeedQuotes() {
return surroundingSpacesNeedQuotes;
}
/**
* Builds immutable CsvPreference instances. The builder pattern allows for additional preferences to be
* added in the future.
*/
public static class Builder {
private final char quoteChar;
private final int delimiterChar;
private final String endOfLineSymbols;
private boolean surroundingSpacesNeedQuotes = false;
/**
* Constructs a Builder with all of the values from an existing CsvPreference instance. Useful if you
* want to base your preferences off one of the existing CsvPreference constants.
*
* @param preference
* the existing preference
*/
public Builder(final CsvPreference preference) {
this.quoteChar = preference.quoteChar;
this.delimiterChar = preference.delimiterChar;
this.endOfLineSymbols = preference.endOfLineSymbols;
this.surroundingSpacesNeedQuotes = preference.surroundingSpacesNeedQuotes;
}
/**
* Constructs a Builder with the mandatory preference values.
*
* @param quoteChar
* matching pairs of this character are used to escape columns containing the delimiter
* @param delimiterChar
* the character separating each column
* @param endOfLineSymbols
* one or more symbols terminating the line, e.g. "\n". Only used for writing.
* @throws IllegalArgumentException
* if quoteChar and delimiterChar are the same character
* @throws NullPointerException
* if endOfLineSymbols is null
*/
public Builder(final char quoteChar, final int delimiterChar, final String endOfLineSymbols) {
if( quoteChar == delimiterChar ) {
throw new IllegalArgumentException(String.format(
"quoteChar and delimiterChar should not be the same character: %c", quoteChar));
} else if( endOfLineSymbols == null ) {
throw new NullPointerException("endOfLineSymbols should not be null");
}
this.quoteChar = quoteChar;
this.delimiterChar = delimiterChar;
this.endOfLineSymbols = endOfLineSymbols;
}
/**
* Flag indicating whether spaces at the beginning or end of a cell should be ignored if they're not surrounded
* by quotes (applicable to both reading and writing CSV). The default is false, as spaces
* "are considered part of a field and should not be ignored" according to RFC 4180.
*
* @param surroundingSpacesNeedQuotes
* flag indicating whether spaces at the beginning or end of a cell should be ignored if they're not
* surrounded by quotes
* @return the updated Builder
*/
public Builder surroundingSpacesNeedQuotes(final boolean surroundingSpacesNeedQuotes) {
this.surroundingSpacesNeedQuotes = surroundingSpacesNeedQuotes;
return this;
}
/**
* Builds the CsvPreference instance.
*
* @return the immutable CsvPreference instance
*/
public CsvPreference build() {
return new CsvPreference(this);
}
}
}