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/* * Copyright 2002-2019 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.StringUtils; /** * Property editor that trims Strings. * * <p>Optionally allows transforming an empty string into a {@code null} value. * Needs to be explicitly registered, e.g. for command binding. * * @author Juergen Hoeller * @see org.springframework.validation.DataBinder#registerCustomEditor */ public class StringTrimmerEditor extends PropertyEditorSupport { @Nullable private final String charsToDelete; private final boolean emptyAsNull; /** * Create a new StringTrimmerEditor. * @param emptyAsNull {@code true} if an empty String is to be * transformed into {@code null} */ public StringTrimmerEditor(boolean emptyAsNull) { this.charsToDelete = null; this.emptyAsNull = emptyAsNull; } /** * Create a new StringTrimmerEditor. * @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 emptyAsNull {@code true} if an empty String is to be * transformed into {@code null} */ public StringTrimmerEditor(String charsToDelete, boolean emptyAsNull) { this.charsToDelete = charsToDelete; this.emptyAsNull = emptyAsNull; } @Override public void setAsText(@Nullable String text) { if (text == null) { setValue(null); } else { String value = text.trim(); if (this.charsToDelete != null) { value = StringUtils.deleteAny(value, this.charsToDelete); } if (this.emptyAsNull && value.isEmpty()) { setValue(null); } else { setValue(value); } } } @Override public String getAsText() { Object value = getValue(); return (value != null ? value.toString() : ""); } }