https://ant.apache.org/: master POM (The Apache Software Foundation) 
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 *  Licensed to the Apache Software Foundation (ASF) under one or more
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 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You 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,
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 *  See the License for the specific language governing permissions and
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 */

package org.apache.tools.ant.taskdefs.condition;

import org.apache.tools.ant.AntTypeDefinition;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.ComponentHelper;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.ProjectComponent;
import org.apache.tools.ant.ProjectHelper;


looks for a task or other Ant type that exists. Existence is defined as
the type is defined, and its implementation class is present. This
will work for datatypes and preset, script and macro definitions.

/**
 * looks for a task or other Ant type that exists. Existence is defined as
 * the type is defined, and its implementation class is present. This
 * will work for datatypes and preset, script and macro definitions.
 */
public class TypeFound extends ProjectComponent implements Condition {

    private String name;
    private String uri;

    
the task or other type to look for

Params:
  • name – the name of the type
/**
     * the task or other type to look for
     * @param name the name of the type
     */
    public void setName(String name) {
        this.name = name;
    }

    
The URI for this definition.

Params:
  • uri – the namespace URI. If this is not set, use the
           default ant namespace.
/**
     * The URI for this definition.
     * @param uri the namespace URI. If this is not set, use the
     *            default ant namespace.
     */
    public void setURI(String uri) {
        this.uri = uri;
    }

    
test for a task or other ant type existing in the current project

Params:
  • typename – the name of the type
Returns:true if the typename exists
/**
     * test for a task or other ant type existing in the current project
     * @param typename the name of the type
     * @return true if the typename exists
     */
    protected boolean doesTypeExist(String typename) {
        ComponentHelper helper =
            ComponentHelper.getComponentHelper(getProject());
        String componentName = ProjectHelper.genComponentName(uri, typename);
        AntTypeDefinition def = helper.getDefinition(componentName);
        if (def == null) {
            return false;
        }
        //now verify that the class has an implementation
        boolean found = def.getExposedClass(getProject()) != null;
        if (!found) {
            String text = helper.diagnoseCreationFailure(componentName, "type");
            log(text, Project.MSG_VERBOSE);
        }
        return found;
    }


    
Is this condition true?

Throws:
Returns:true if the condition is true
/**
     * Is this condition true?
     * @return true if the condition is true
     * @exception BuildException if an error occurs
     */
    @Override
    public boolean eval() throws BuildException {
        if (name == null) {
            throw new BuildException("No type specified");
        }
        return doesTypeExist(name);
    }
}