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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
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 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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package org.graalvm.util;

import java.io.DataOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.charset.StandardCharsets;

A stream that can write (trivial) values together with their data type, for use with TypedDataInputStream.
/** * A stream that can write (trivial) values together with their data type, for use with * {@link TypedDataInputStream}. */
public class TypedDataOutputStream extends DataOutputStream {
Determines if value is supported by writeTypedValue(Object).
/** Determines if {@code value} is supported by {@link #writeTypedValue(Object)}. */
public static boolean isValueSupported(Object value) { if (value == null) { return false; } Class<?> valueClass = value.getClass(); return valueClass == Boolean.class || valueClass == Byte.class || valueClass == Short.class || valueClass == Character.class || valueClass == Integer.class || valueClass == Long.class || valueClass == Float.class || valueClass == Double.class || valueClass == String.class || value.getClass().isEnum(); } public TypedDataOutputStream(OutputStream out) { super(out); }
Writes the value that is represented by the given non-null object, together with information on the value's data type.
Params:
Throws:
/** * Writes the value that is represented by the given non-null object, together with information * on the value's data type. * * @param value A value of a {@linkplain #isValueSupported supported type}. * @exception IllegalArgumentException when the provided type is not supported. * @exception IOException in case of an I/O error. */
public void writeTypedValue(Object value) throws IOException { Class<?> valueClz = value.getClass(); if (valueClz == Boolean.class) { this.writeByte('Z'); this.writeBoolean((Boolean) value); } else if (valueClz == Byte.class) { this.writeByte('B'); this.writeByte((Byte) value); } else if (valueClz == Short.class) { this.writeByte('S'); this.writeShort((Short) value); } else if (valueClz == Character.class) { this.writeByte('C'); this.writeChar((Character) value); } else if (valueClz == Integer.class) { this.writeByte('I'); this.writeInt((Integer) value); } else if (valueClz == Long.class) { this.writeByte('J'); this.writeLong((Long) value); } else if (valueClz == Float.class) { this.writeByte('F'); this.writeFloat((Float) value); } else if (valueClz == Double.class) { this.writeByte('D'); this.writeDouble((Double) value); } else if (valueClz == String.class) { writeStringValue((String) value); } else if (valueClz.isEnum()) { writeStringValue(((Enum<?>) value).name()); } else { throw new IllegalArgumentException(String.format("Unsupported type: Value: %s, Value type: %s", value, valueClz)); } } private void writeStringValue(String value) throws IOException { this.writeByte('U'); byte[] bytes = value.getBytes(StandardCharsets.UTF_8); this.writeInt(bytes.length); this.write(bytes); } }