org.hibernate.validator.internal.engine.messageinterpolation.InterpolationTerm Maven / Gradle / Ivy
/*
* Hibernate Validator, declare and validate application constraints
*
* License: Apache License, Version 2.0
* See the license.txt file in the root directory or .
*/
package org.hibernate.validator.internal.engine.messageinterpolation;
import java.util.Locale;
import javax.el.ExpressionFactory;
import javax.validation.MessageInterpolator;
/**
* Helper class dealing with the interpolation of a single message parameter or expression extracted from a message
* descriptor.
*
* @author Hardy Ferentschik
*/
public class InterpolationTerm {
/**
* Meta character to designate an EL expression.
*/
private static final String EL_DESIGNATION_CHARACTER = "$";
/**
* The actual expression (parameter or EL expression).
*/
private final String expression;
/**
* The type of the expression.
*/
private final InterpolationTermType type;
/**
* The resolver for the expression.
*/
private final TermResolver resolver;
/**
* Create an interpolation term for an expression.
* @param expression the expression.
* @param locale the locale.
* @param expressionFactory the expression factory to use if the expression uses EL.
*/
public InterpolationTerm(String expression, Locale locale, ExpressionFactory expressionFactory) {
this.expression = expression;
if ( isElExpression( expression ) ) {
this.type = InterpolationTermType.EL;
this.resolver = new ElTermResolver( locale, expressionFactory );
}
else {
this.type = InterpolationTermType.PARAMETER;
this.resolver = new ParameterTermResolver();
}
}
public static boolean isElExpression(String expression) {
return expression.startsWith( EL_DESIGNATION_CHARACTER );
}
public String interpolate(MessageInterpolator.Context context) {
return resolver.interpolate( context, expression );
}
@Override
public String toString() {
final StringBuilder sb = new StringBuilder();
sb.append( "InterpolationExpression" );
sb.append( "{expression='" ).append( expression ).append( '\'' );
sb.append( ", type=" ).append( type );
sb.append( '}' );
return sb.toString();
}
}