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/*
* Copyright 2003-2007 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
*
* http://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 groovy.lang;
import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.regex.Pattern;
import org.codehaus.groovy.runtime.DefaultGroovyMethods;
import org.codehaus.groovy.runtime.InvokerHelper;
/**
* Represents a String which contains embedded values such as "hello there
* ${user} how are you?" which can be evaluated lazily. Advanced users can
* iterate over the text and values to perform special processing, such as for
* performing SQL operations, the values can be substituted for ? and the
* actual value objects can be bound to a JDBC statement. The lovely name of
* this class was suggested by Jules Gosnell and was such a good idea, I
* couldn't resist :)
*
* @author James Strachan
* @version $Revision: 8533 $
*/
public abstract class GString extends GroovyObjectSupport implements Comparable, CharSequence, Writable, Buildable {
private Object[] values;
public GString(Object values) {
this.values = (Object[]) values;
}
public GString(Object[] values) {
this.values = values;
}
// will be static in an instance
public abstract String[] getStrings();
/**
* Overloaded to implement duck typing for Strings
* so that any method that can't be evaluated on this
* object will be forwarded to the toString() object instead.
*/
public Object invokeMethod(String name, Object args) {
try {
return super.invokeMethod(name, args);
}
catch (MissingMethodException e) {
// lets try invoke the method on the real String
return InvokerHelper.invokeMethod(toString(), name, args);
}
}
public Object[] getValues() {
return values;
}
public GString plus(GString that) {
List stringList = new ArrayList();
List valueList = new ArrayList();
stringList.addAll(Arrays.asList(getStrings()));
valueList.addAll(Arrays.asList(getValues()));
if (stringList.size() > valueList.size()) {
valueList.add("");
}
stringList.addAll(Arrays.asList(that.getStrings()));
valueList.addAll(Arrays.asList(that.getValues()));
final String[] newStrings = new String[stringList.size()];
stringList.toArray(newStrings);
Object[] newValues = valueList.toArray();
return new GString(newValues) {
public String[] getStrings() {
return newStrings;
}
};
}
public GString plus(String that) {
String[] currentStrings = getStrings();
String[] newStrings = null;
Object[] newValues = null;
newStrings = new String[currentStrings.length + 1];
newValues = new Object[getValues().length + 1];
int lastIndex = currentStrings.length;
System.arraycopy(currentStrings, 0, newStrings, 0, lastIndex);
System.arraycopy(getValues(), 0, newValues, 0, getValues().length);
newStrings[lastIndex] = that;
newValues[getValues().length] = "";
final String[] finalStrings = newStrings;
return new GString(newValues) {
public String[] getStrings() {
return finalStrings;
}
};
}
public int getValueCount() {
return values.length;
}
public Object getValue(int idx) {
return values[idx];
}
public String toString() {
StringWriter buffer = new StringWriter();
try {
writeTo(buffer);
}
catch (IOException e) {
throw new StringWriterIOException(e);
}
return buffer.toString();
}
public Writer writeTo(Writer out) throws IOException {
String[] s = getStrings();
int numberOfValues = values.length;
for (int i = 0, size = s.length; i < size; i++) {
out.write(s[i]);
if (i < numberOfValues) {
final Object value = values[i];
if (value instanceof Closure) {
final Closure c = (Closure)value;
if (c.getMaximumNumberOfParameters() == 0) {
InvokerHelper.write(out, c.call(null));
} else if (c.getMaximumNumberOfParameters() == 1) {
c.call(new Object[]{out});
} else {
throw new GroovyRuntimeException("Trying to evaluate a GString containing a Closure taking "
+ c.getMaximumNumberOfParameters() + " parameters");
}
} else {
InvokerHelper.write(out, value);
}
}
}
return out;
}
/* (non-Javadoc)
* @see groovy.lang.Buildable#build(groovy.lang.GroovyObject)
*/
public void build(final GroovyObject builder) {
final String[] s = getStrings();
final int numberOfValues = values.length;
for (int i = 0, size = s.length; i < size; i++) {
builder.getProperty("mkp");
builder.invokeMethod("yield", new Object[]{s[i]});
if (i < numberOfValues) {
builder.getProperty("mkp");
builder.invokeMethod("yield", new Object[]{values[i]});
}
}
}
public boolean equals(Object that) {
if (that instanceof GString) {
return equals((GString) that);
}
return false;
}
public boolean equals(GString that) {
return toString().equals(that.toString());
}
public int hashCode() {
return 37 + toString().hashCode();
}
public int compareTo(Object that) {
return toString().compareTo(that.toString());
}
public char charAt(int index) {
return toString().charAt(index);
}
public int length() {
return toString().length();
}
public CharSequence subSequence(int start, int end) {
return toString().subSequence(start, end);
}
/**
* Turns a String into a regular expression pattern
*
* @return the regular expression pattern
*/
public Pattern negate() {
return DefaultGroovyMethods.bitwiseNegate(toString());
}
}