com.github.fge.uritemplate.render.StringRenderer Maven / Gradle / Ivy

Go to download
/*
 * Copyright (c) 2014, Francis Galiegue ([email protected])
 *
 * This software is dual-licensed under:
 *
 * - the Lesser General Public License (LGPL) version 3.0 or, at your option, any
 *   later version;
 * - the Apache Software License (ASL) version 2.0.
 *
 * The text of this file and of both licenses is available at the root of this
 * project or, if you have the jar distribution, in directory META-INF/, under
 * the names LGPL-3.0.txt and ASL-2.0.txt respectively.
 *
 * Direct link to the sources:
 *
 * - LGPL 3.0: https://www.gnu.org/licenses/lgpl-3.0.txt
 * - ASL 2.0: http://www.apache.org/licenses/LICENSE-2.0.txt
 */

package com.github.fge.uritemplate.render;

import com.github.fge.uritemplate.URITemplateException;
import com.github.fge.uritemplate.expression.ExpressionType;
import com.github.fge.uritemplate.vars.specs.VariableSpec;
import com.github.fge.uritemplate.vars.values.VariableValue;
import com.google.common.collect.ImmutableList;

import java.util.List;

/**
 * String value renderer
 *
 * Rendering of a string value is the only event where the returned list
 * cannot be empty. Concurrently, it will always have a single element.
 */
public final class StringRenderer
    extends ValueRenderer
{
    public StringRenderer(final ExpressionType type)
    {
        super(type);
    }

    @Override
    public List render(final VariableSpec varspec,
        final VariableValue value)
        throws URITemplateException
    {
        return ImmutableList.of(doRender(varspec, value.getScalarValue()));
    }

    private String doRender(final VariableSpec varspec, final String value)
    {
        final StringBuilder sb = new StringBuilder(value.length());
        if (named) {
            // Note: variable names do not contain any character susceptible to
            // be percent encoded, so we leave them intact
            sb.append(varspec.getName());
            if (value.isEmpty())
                return sb.append(ifEmpty).toString();
                //return ret + ifEmpty;
            sb.append('=');
        }
        // Account for a prefix, if any. Note: explode modifier is ignored.
        final int prefixLen = varspec.getPrefixLength();
        if (prefixLen == -1)
            return sb.append(pctEncode(value)).toString();
        final int len = value.codePointCount(0, value.length());
        return len <= prefixLen ? sb.append(pctEncode(value)).toString()
            :sb.append(pctEncode(nFirstChars(value, prefixLen))).toString();
    }

    private static String nFirstChars(final String s, final int n)
    {
        int realIndex = n;
        while (s.codePointCount(0, realIndex) != n)
            realIndex++;
        return s.substring(0, realIndex);
    }
}