org.commoncrawl.util.RPCStructIntrospector.java Source code

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Here is the source code for org.commoncrawl.util.RPCStructIntrospector.java

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/**
 * Copyright 2008 - CommonCrawl Foundation
 * 
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation, either version 3 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 **/

package org.commoncrawl.util;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.commoncrawl.protocol.CrawlURLMetadata;
import org.commoncrawl.rpc.base.shared.RPCStruct;

/**
 * 
 * @author rana
 *
 */
public class RPCStructIntrospector {

    private static final Log LOG = LogFactory.getLog(RPCStructIntrospector.class);
    HashSet<String> propertyNames = new HashSet<String>();
    HashMap<String, Method> getters = new HashMap<String, Method>();
    Class theClass;

    public RPCStructIntrospector(Class classType) {
        theClass = classType;
        for (Field field : classType.getDeclaredFields()) {
            System.out.println("Found Field:" + field.getName());
            if (!field.isEnumConstant()) {
                propertyNames.add(field.getName());
            }
        }

        for (Method m : classType.getDeclaredMethods()) {
            System.out.println("Found Method:" + m.getName());
            if (m.getName().startsWith("get")) {
                getters.put(m.getName(), m);
            }
        }
    }

    public Set<String> getPropertyNames() {
        return propertyNames;
    }

    static String toCamelCase(String name) {
        char firstChar = name.charAt(0);
        if (Character.isLowerCase(firstChar)) {
            return "" + Character.toUpperCase(firstChar) + name.substring(1);
        }
        return name;
    }

    public String getStringValueGivenName(RPCStruct object, String propertyName) {
        Method m;
        try {
            m = theClass.getMethod("get" + toCamelCase(propertyName));
            if (m != null) {
                try {
                    return m.invoke(object, new Object[0]).toString();
                } catch (IllegalArgumentException e) {
                    LOG.error(CCStringUtils.stringifyException(e));
                } catch (IllegalAccessException e) {
                    LOG.error(CCStringUtils.stringifyException(e));
                } catch (InvocationTargetException e) {
                    LOG.error(CCStringUtils.stringifyException(e));
                }
            }

        } catch (Exception e) {
            LOG.error(CCStringUtils.stringifyException(e));
        }
        return "NOT-FOUND";
    }

    public double getDoubleValueGivenName(RPCStruct object, String propertyName) {
        Method m;
        try {
            m = theClass.getMethod("get" + toCamelCase(propertyName));

            if (m != null) {
                try {
                    Object value = m.invoke(object, new Object[0]).toString();
                    if (value instanceof String) {
                        return Double.parseDouble((String) value);
                    } else if (value instanceof Integer) {
                        return (double) ((Integer) value).doubleValue();
                    } else if (value instanceof Long) {
                        return (double) ((Long) value).doubleValue();
                    } else if (value instanceof Short) {
                        return (double) ((Short) value).doubleValue();
                    } else if (value instanceof Float) {
                        return (double) ((Float) value).doubleValue();
                    } else if (value instanceof Byte) {
                        return (double) ((Byte) value).doubleValue();
                    } else if (value instanceof Boolean) {
                        return (double) (((Boolean) value).booleanValue() ? 1.0f : 0.0f);
                    } else {
                        throw new RuntimeException("Unable to convert Return Value to double:" + value.toString());
                    }
                } catch (IllegalArgumentException e) {
                    LOG.error(CCStringUtils.stringifyException(e));
                } catch (IllegalAccessException e) {
                    LOG.error(CCStringUtils.stringifyException(e));
                } catch (InvocationTargetException e) {
                    LOG.error(CCStringUtils.stringifyException(e));
                }
            }
        } catch (Exception e) {
            LOG.error(CCStringUtils.stringifyException(e));
        }
        return Double.NaN;
    }

    public void dumpGetters() {
        for (String name : getters.keySet()) {
            System.out.println(name);
        }
    }

    public void dumpProperties(Object o) {
        for (Method m : getters.values()) {
            try {
                System.out.println(m.invoke(o, null));
            } catch (IllegalArgumentException e) {
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (InvocationTargetException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) {
        RPCStructIntrospector test = new RPCStructIntrospector(CrawlURLMetadata.class);
        CrawlURLMetadata metadata = new CrawlURLMetadata();
        test.dumpGetters();
        test.dumpProperties(metadata);
    }
}