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/* * Copyright 2002-2018 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.beans.propertyeditors; import java.beans.PropertyEditorSupport; import org.springframework.lang.Nullable; import org.springframework.util.ObjectUtils; import org.springframework.util.StringUtils; /** * Custom {@link java.beans.PropertyEditor} for String arrays. * * <p>Strings must be in CSV format, with a customizable separator. * By default values in the result are trimmed of whitespace. * * @author Rod Johnson * @author Juergen Hoeller * @author Dave Syer * @see org.springframework.util.StringUtils#delimitedListToStringArray * @see org.springframework.util.StringUtils#arrayToDelimitedString */ public class StringArrayPropertyEditor extends PropertyEditorSupport { /** * Default separator for splitting a String: a comma (","). */ public static final String DEFAULT_SEPARATOR = ","; private final String separator; @Nullable private final String charsToDelete; private final boolean emptyArrayAsNull; private final boolean trimValues; /** * Create a new StringArrayPropertyEditor with the default separator * (a comma). * <p>An empty text (without elements) will be turned into an empty array. */ public StringArrayPropertyEditor() { this(DEFAULT_SEPARATOR, null, false); } /** * Create a new StringArrayPropertyEditor with the given separator. * <p>An empty text (without elements) will be turned into an empty array. * @param separator the separator to use for splitting a {@link String} */ public StringArrayPropertyEditor(String separator) { this(separator, null, false); } /** * Create a new StringArrayPropertyEditor with the given separator. * @param separator the separator to use for splitting a {@link String} * @param emptyArrayAsNull {@code true} if an empty String array * is to be transformed into {@code null} */ public StringArrayPropertyEditor(String separator, boolean emptyArrayAsNull) { this(separator, null, emptyArrayAsNull); } /** * Create a new StringArrayPropertyEditor with the given separator. * @param separator the separator to use for splitting a {@link String} * @param emptyArrayAsNull {@code true} if an empty String array * is to be transformed into {@code null} * @param trimValues {@code true} if the values in the parsed arrays * are to be trimmed of whitespace (default is true). */ public StringArrayPropertyEditor(String separator, boolean emptyArrayAsNull, boolean trimValues) { this(separator, null, emptyArrayAsNull, trimValues); } /** * Create a new StringArrayPropertyEditor with the given separator. * @param separator the separator to use for splitting a {@link String} * @param charsToDelete a set of characters to delete, in addition to * trimming an input String. Useful for deleting unwanted line breaks: * e.g. "\r\n\f" will delete all new lines and line feeds in a String. * @param emptyArrayAsNull {@code true} if an empty String array * is to be transformed into {@code null} */ public StringArrayPropertyEditor(String separator, @Nullable String charsToDelete, boolean emptyArrayAsNull) { this(separator, charsToDelete, emptyArrayAsNull, true); } /** * Create a new StringArrayPropertyEditor with the given separator. * @param separator the separator to use for splitting a {@link String} * @param charsToDelete a set of characters to delete, in addition to * trimming an input String. Useful for deleting unwanted line breaks: * e.g. "\r\n\f" will delete all new lines and line feeds in a String. * @param emptyArrayAsNull {@code true} if an empty String array * is to be transformed into {@code null} * @param trimValues {@code true} if the values in the parsed arrays * are to be trimmed of whitespace (default is true). */ public StringArrayPropertyEditor(String separator, @Nullable String charsToDelete, boolean emptyArrayAsNull, boolean trimValues) { this.separator = separator; this.charsToDelete = charsToDelete; this.emptyArrayAsNull = emptyArrayAsNull; this.trimValues = trimValues; } @Override public void setAsText(String text) throws IllegalArgumentException { String[] array = StringUtils.delimitedListToStringArray(text, this.separator, this.charsToDelete); if (this.trimValues) { array = StringUtils.trimArrayElements(array); } if (this.emptyArrayAsNull && array.length == 0) { setValue(null); } else { setValue(array); } } @Override public String getAsText() { return StringUtils.arrayToDelimitedString(ObjectUtils.toObjectArray(getValue()), this.separator); } }