All Downloads are FREE. Search and download functionalities are using the official Maven repository.
Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance.
Project price only 1 $
You can buy this project and download/modify it how often you want.
io.cdap.wrangler.expression.EL Maven / Gradle / Ivy
/*
* Copyright © 2017-2019 Cask Data, Inc.
*
* 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 io.cdap.wrangler.expression;
import com.google.common.base.Joiner;
import com.google.common.base.Strings;
import io.cdap.cdap.api.common.Bytes;
import io.cdap.functions.DDL;
import io.cdap.functions.DataQuality;
import io.cdap.functions.Dates;
import io.cdap.functions.GeoFences;
import io.cdap.functions.Global;
import io.cdap.functions.JSON;
import org.apache.commons.jexl3.JexlBuilder;
import org.apache.commons.jexl3.JexlEngine;
import org.apache.commons.jexl3.JexlException;
import org.apache.commons.jexl3.JexlInfo;
import org.apache.commons.jexl3.JexlScript;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang3.StringEscapeUtils;
import org.apache.commons.logging.Log;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* This class EL is a Expression Language Handler.
*/
public final class EL {
private Set variables = new HashSet<>();
private final JexlEngine engine;
private JexlScript script = null;
public EL(ELRegistration registration) {
engine = new JexlBuilder()
.namespaces(registration.functions())
.silent(false)
.cache(1024)
.strict(true)
.logger(new NullLogger())
.create();
}
public void compile(String expression) throws ELException {
variables.clear();
try {
script = engine.createScript(expression);
Set> varSet = script.getVariables();
for (List vars : varSet) {
variables.add(Joiner.on(".").join(vars));
}
} catch (JexlException e) {
// JexlException.getMessage() uses 'io.cdap.wrangler.expression.EL' class name in the error message.
// So instead use info object to get information about error message and create custom error message.
JexlInfo info = e.getInfo();
throw new ELException(
String.format("Error encountered while executing '%s' at line '%d' and column '%d'. " +
"Make sure a valid jexl transformation is provided.",
info.getDetail().toString(), info.getLine(), info.getColumn()), e);
} catch (Exception e) {
throw new ELException(e);
}
}
public Set variables() {
return variables;
}
public ELResult execute(ELContext context, boolean nullMissingFields) throws ELException {
try {
if (nullMissingFields) {
for (String variable : variables) {
if (!context.has(variable)) {
context.add(variable, null);
}
}
}
Object value = script.execute(context);
ELResult variable = new ELResult(value);
return variable;
} catch (JexlException e) {
// JexlException.getMessage() uses 'io.cdap.wrangler.expression.EL' class name in the error message.
// So instead use info object to get information about error message and create custom error message.
JexlInfo info = e.getInfo();
throw new ELException(
String.format("Error encountered while executing '%s', at line '%d' and column '%d'. " +
"Make sure a valid jexl transformation is provided.",
info.getDetail().toString(), info.getLine(), info.getColumn()), e);
} catch (NumberFormatException e) {
throw new ELException("Type mismatch. Change type of constant " +
"or convert to right data type using conversion functions available. Reason : "
+ e.getMessage(), e);
} catch (Exception e) {
if (e.getCause() != null) {
throw new ELException(e.getCause().getMessage(), e);
} else {
throw new ELException(e);
}
}
}
public ELResult execute(ELContext context) throws ELException {
return execute(context, true);
}
/**
* @return List of registered functions.
*/
public static final class DefaultFunctions implements ELRegistration {
@Override
public Map functions() {
Map functions = new HashMap<>();
functions.put(null, Global.class);
functions.put("date", Dates.class);
functions.put("json", JSON.class);
functions.put("math", Math.class);
functions.put("string", StringUtils.class);
functions.put("strings", Strings.class);
functions.put("escape", StringEscapeUtils.class);
functions.put("bytes", Bytes.class);
functions.put("arrays", Arrays.class);
functions.put("dq", DataQuality.class);
functions.put("ddl", DDL.class);
functions.put("geo", GeoFences.class);
return functions;
}
}
private final class NullLogger implements Log {
@Override
public void debug(Object o) {
}
@Override
public void debug(Object o, Throwable throwable) {
}
@Override
public void error(Object o) {
}
@Override
public void error(Object o, Throwable throwable) {
}
@Override
public void fatal(Object o) {
}
@Override
public void fatal(Object o, Throwable throwable) {
}
@Override
public void info(Object o) {
}
@Override
public void info(Object o, Throwable throwable) {
}
@Override
public boolean isDebugEnabled() {
return false;
}
@Override
public boolean isErrorEnabled() {
return false;
}
@Override
public boolean isFatalEnabled() {
return false;
}
@Override
public boolean isInfoEnabled() {
return false;
}
@Override
public boolean isTraceEnabled() {
return false;
}
@Override
public boolean isWarnEnabled() {
return false;
}
@Override
public void trace(Object o) {
}
@Override
public void trace(Object o, Throwable throwable) {
}
@Override
public void warn(Object o) {
}
@Override
public void warn(Object o, Throwable throwable) {
}
}
}
