com.fasterxml.jackson.jr.ob.impl.EnumReader Maven / Gradle / Ivy
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package com.fasterxml.jackson.jr.ob.impl;
import java.io.IOException;
import java.util.Map;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonToken;
import com.fasterxml.jackson.jr.ob.JSONObjectException;
import com.fasterxml.jackson.jr.ob.api.ValueReader;
/**
* Reader for Enum values: needed because we need a simple {@link java.util.Map}
* for efficient conversion from id (gotten with {@link java.lang.Enum#toString()}
* to value.
*
* In future we could consider alternatively allowing use of
* {@link java.lang.Enum#name()} for id.
*/
public class EnumReader extends ValueReader
{
protected final Object[] _byIndex;
protected final Map _byName;
public EnumReader(Class> enumType,
Object[] byIndex, Map byName) {
super(enumType);
_byIndex = byIndex;
_byName = byName;
}
private String desc() {
return _byIndex[0].getClass().getName();
}
@Override
public Object readNext(JSONReader reader, JsonParser p) throws IOException {
String name = p.nextTextValue();
if (name != null) {
return _enum(name);
}
return read(reader, p);
}
@Override
public Object read(JSONReader reader, JsonParser p) throws IOException {
if (p.hasToken(JsonToken.VALUE_NUMBER_INT)) {
int ix = p.getIntValue();
if (ix < 0 || ix >= _byIndex.length) {
throw new JSONObjectException("Failed to bind Enum "+desc()+" with index "+ix
+" (has "+_byIndex.length+" values)");
}
return _byIndex[ix];
}
if (p.hasToken(JsonToken.VALUE_NULL)) {
return null;
}
if (p.hasToken(JsonToken.VALUE_STRING)) {
return _enum(p.getValueAsString().trim());
}
throw JSONObjectException.from(p, "Can not read Enum `"+_valueType.getName()+"` from "
+_tokenDesc(p, p.currentToken()));
}
private Object _enum(String id) throws IOException
{
Object e = _byName.get(id);
if (e == null) {
throw new JSONObjectException("Failed to find Enum of type "+desc()+" for value '"+id+"'");
}
return e;
}
}