org.eclipse.equinox.internal.p2.metadata.TouchpointInstruction Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2008, 2010 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
* EclipseSource - ongoing development
*******************************************************************************/
package org.eclipse.equinox.internal.p2.metadata;
import org.eclipse.equinox.p2.metadata.MetadataFactory;
import java.util.Map;
import java.util.Map.Entry;
import org.eclipse.equinox.p2.metadata.ITouchpointInstruction;
/**
* A touchpoint instruction contains either a sequence of instruction statements
* to be executed during a particular engine phase, or some simple string value
* that is needed by a touchpoint to execute its phases.
*
* The format of a touchpoint instruction statement sequence is as follows:
*
* statement-sequence :
* | statement ';'
* | statement-sequence statement
* ;
*
*Where a statement is of the format:
*
* statement :
* | actionName '(' parameters ')'
* ;
*
* parameters :
* | // empty
* | parameter
* | parameters ',' parameter
* ;
*
* parameter :
* | paramName ':' paramValue
* ;
*
* actionName, paramName, paramValue :
* | String
* ;
*
* @noextend This class is not intended to be subclassed by clients.
* @see MetadataFactory#createTouchpointInstruction(String, String)
*/
public class TouchpointInstruction implements ITouchpointInstruction {
private final String body;
private final String importAttribute;
/**
* Encodes an action statement in string form. This method will
* take care of escaping any illegal characters in function parameter values.
*
* @param actionName The name of the action.
* @param parameters The function's parameters. This is a Map
* where the keys are parameter names, and the values are parameter values
* @return An encoded touchpoint instruction statement
*/
public static String encodeAction(String actionName, Map parameters) {
StringBuffer result = new StringBuffer(actionName);
result.append('(');
boolean first = true;
for (Entry entry : parameters.entrySet()) {
if (first)
first = false;
else
result.append(',');
result.append(entry.getKey());
result.append(':');
appendEncoded(result, entry.getValue());
}
result.append(')').append(';');
return result.toString();
}
/**
* Append the given value to the given buffer, encoding any illegal characters
* with appropriate escape sequences.
*/
private static void appendEncoded(StringBuffer buf, String value) {
char[] chars = value.toCharArray();
for (int i = 0; i < chars.length; i++) {
switch (chars[i]) {
case '$' :
case ',' :
case ':' :
case ';' :
case '{' :
case '}' :
buf.append("${#").append(Integer.toString(chars[i])).append('}'); //$NON-NLS-1$
break;
default :
buf.append(chars[i]);
}
}
}
/**
* Clients must use the factory method on {@link MetadataFactory}.
*/
public TouchpointInstruction(String body, String importAttribute) {
this.body = body;
this.importAttribute = importAttribute;
}
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (!(obj instanceof ITouchpointInstruction))
return false;
ITouchpointInstruction other = (ITouchpointInstruction) obj;
if (body == null) {
if (other.getBody() != null)
return false;
} else if (!body.equals(other.getBody()))
return false;
if (importAttribute == null) {
if (other.getImportAttribute() != null)
return false;
} else if (!importAttribute.equals(other.getImportAttribute()))
return false;
return true;
}
/**
* Returns the body of this touchpoint instruction. The body is either a sequence
* of instruction statements, or a simple string value.
*
* @return The body of this touchpoint instruction
*/
public String getBody() {
return body;
}
//TODO What is this? Please doc
public String getImportAttribute() {
return importAttribute;
}
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((body == null) ? 0 : body.hashCode());
result = prime * result + ((importAttribute == null) ? 0 : importAttribute.hashCode());
return result;
}
/**
* Returns a string representation of this instruction for debugging purposes only.
*/
public String toString() {
return "Instruction[" + body + ',' + importAttribute + ']'; //$NON-NLS-1$
}
}