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Add java.util.logging backend
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‎NEXT_CHANGELOG.md‎

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### Internal Changes
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* Introduced a logging abstraction (`com.databricks.sdk.core.logging`) to decouple the SDK from a specific logging backend.
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* Added `java.util.logging` as a supported alternative logging backend. Activate it with `LoggerFactory.setDefault(JulLoggerFactory.INSTANCE)`.
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### API Changes
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* Add `createCatalog()`, `createSyncedTable()`, `deleteCatalog()`, `deleteSyncedTable()`, `getCatalog()` and `getSyncedTable()` methods for `workspaceClient.postgres()` service.

‎databricks-sdk-java/src/main/java/com/databricks/sdk/core/logging/JulLogger.java‎

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package com.databricks.sdk.core.logging;
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import java.util.Arrays;
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import java.util.function.Supplier;
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import java.util.logging.Level;
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import java.util.logging.LogRecord;
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/** Delegates logging calls to a {@code java.util.logging.Logger}, translating SLF4J conventions. */
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class JulLogger extends Logger {
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private static final String LOGGING_PACKAGE = "com.databricks.sdk.core.logging.";
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private final java.util.logging.Logger delegate;
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JulLogger(java.util.logging.Logger delegate) {
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this.delegate = delegate;
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}
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@Override
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public void debug(String msg) {
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log(Level.FINE, msg, null);
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}
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@Override
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public void debug(String format, Object... args) {
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log(Level.FINE, format, args);
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}
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@Override
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public void debug(Supplier<String> msgSupplier) {
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if (delegate.isLoggable(Level.FINE)) {
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log(Level.FINE, msgSupplier.get(), null);
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}
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}
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@Override
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public void info(String msg) {
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log(Level.INFO, msg, null);
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}
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@Override
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public void info(String format, Object... args) {
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log(Level.INFO, format, args);
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}
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@Override
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public void info(Supplier<String> msgSupplier) {
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if (delegate.isLoggable(Level.INFO)) {
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log(Level.INFO, msgSupplier.get(), null);
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}
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}
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@Override
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public void warn(String msg) {
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log(Level.WARNING, msg, null);
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}
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@Override
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public void warn(String format, Object... args) {
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log(Level.WARNING, format, args);
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}
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@Override
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public void warn(Supplier<String> msgSupplier) {
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if (delegate.isLoggable(Level.WARNING)) {
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log(Level.WARNING, msgSupplier.get(), null);
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}
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}
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@Override
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public void error(String msg) {
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log(Level.SEVERE, msg, null);
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}
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@Override
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public void error(String format, Object... args) {
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log(Level.SEVERE, format, args);
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}
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@Override
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public void error(Supplier<String> msgSupplier) {
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if (delegate.isLoggable(Level.SEVERE)) {
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log(Level.SEVERE, msgSupplier.get(), null);
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}
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}
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private void log(Level level, String format, Object[] args) {
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if (!delegate.isLoggable(level)) {
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return;
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}
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Throwable thrown = (args != null) ? extractThrowable(format, args) : null;
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String message = (args != null) ? formatMessage(format, args) : format;
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LogRecord record = new LogRecord(level, message);
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record.setLoggerName(delegate.getName());
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if (thrown != null) {
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record.setThrown(thrown);
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}
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inferCaller(record);
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delegate.log(record);
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}
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/**
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* Sets the source class and method on a {@link LogRecord} by walking the call stack to find the
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* first frame outside this logging package.
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*
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* <p>JUL normally infers caller information automatically by scanning the stack for the first
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* frame after its own {@code java.util.logging.Logger} methods. Because {@code JulLogger} wraps
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* the JUL logger, that automatic inference stops at {@code JulLogger} or its helper methods
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* instead of reaching the actual SDK class that initiated the log call. Without this correction,
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* every log record would be attributed to {@code JulLogger}, making JUL output useless for
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* identifying the real call site.
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*/
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private static void inferCaller(LogRecord record) {
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StackTraceElement[] stack = new Throwable().getStackTrace();
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for (StackTraceElement frame : stack) {
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if (!frame.getClassName().startsWith(LOGGING_PACKAGE)) {
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record.setSourceClassName(frame.getClassName());
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record.setSourceMethodName(frame.getMethodName());
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return;
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}
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}
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}
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/**
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* Replaces SLF4J-style {@code {}} placeholders with argument values, matching the semantics of
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* SLF4J's {@code MessageFormatter.arrayFormat}:
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*
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* <ul>
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* <li>A trailing {@link Throwable} is unconditionally excluded from formatting.
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* <li>A backslash before {@code {}} escapes it as a literal {@code {}}.
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* <li>Array arguments are rendered with {@link Arrays#deepToString}.
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* <li>A {@code null} format string returns {@code null}.
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* </ul>
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*/
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static String formatMessage(String format, Object[] args) {
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if (format == null) {
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return null;
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}
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if (args == null || args.length == 0) {
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return format;
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}
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int usableArgs = args.length;
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if (args[usableArgs - 1] instanceof Throwable) {
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usableArgs--;
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}
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StringBuilder sb = new StringBuilder(format.length() + 32);
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int argIdx = 0;
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int i = 0;
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while (i < format.length()) {
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if (i + 1 < format.length() && format.charAt(i) == '{' && format.charAt(i + 1) == '}') {
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if (i > 0 && format.charAt(i - 1) == '\\') {
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sb.setLength(sb.length() - 1);
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sb.append("{}");
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} else if (argIdx < usableArgs) {
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sb.append(renderArg(args[argIdx++]));
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} else {
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sb.append("{}");
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}
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i += 2;
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} else {
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sb.append(format.charAt(i));
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i++;
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}
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}
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return sb.toString();
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}
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private static String renderArg(Object arg) {
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if (arg == null) {
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return "null";
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}
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if (arg instanceof Object[]) {
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return Arrays.deepToString((Object[]) arg);
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}
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if (arg.getClass().isArray()) {
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return primitiveArrayToString(arg);
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}
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return arg.toString();
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}
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private static String primitiveArrayToString(Object array) {
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if (array instanceof boolean[]) return Arrays.toString((boolean[]) array);
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if (array instanceof byte[]) return Arrays.toString((byte[]) array);
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if (array instanceof char[]) return Arrays.toString((char[]) array);
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if (array instanceof short[]) return Arrays.toString((short[]) array);
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if (array instanceof int[]) return Arrays.toString((int[]) array);
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if (array instanceof long[]) return Arrays.toString((long[]) array);
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if (array instanceof float[]) return Arrays.toString((float[]) array);
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if (array instanceof double[]) return Arrays.toString((double[]) array);
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return Arrays.deepToString(new Object[] {array});
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}
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/**
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* Returns the last argument if it is a {@link Throwable}, unconditionally. This matches SLF4J's
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* {@code NormalizedParameters.getThrowableCandidate}, which always extracts a trailing Throwable
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* regardless of how many {@code {}} placeholders the format string contains.
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*/
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static Throwable extractThrowable(String format, Object[] args) {
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if (args == null || args.length == 0) {
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return null;
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}
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Object last = args[args.length - 1];
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if (last instanceof Throwable) {
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return (Throwable) last;
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}
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return null;
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}
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}

‎databricks-sdk-java/src/main/java/com/databricks/sdk/core/logging/JulLoggerFactory.java‎

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package com.databricks.sdk.core.logging;
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/**
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* A {@link LoggerFactory} backed by {@code java.util.logging}. Always available on any JRE.
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*
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* <p>Use this when SLF4J is not desirable:
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*
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* <pre>{@code
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* LoggerFactory.setDefault(JulLoggerFactory.INSTANCE);
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* }</pre>
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*/
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public class JulLoggerFactory extends LoggerFactory {
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public static final JulLoggerFactory INSTANCE = new JulLoggerFactory();
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@Override
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protected Logger createLogger(Class<?> type) {
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return new JulLogger(java.util.logging.Logger.getLogger(type.getName()));
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}
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@Override
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protected Logger createLogger(String name) {
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return new JulLogger(java.util.logging.Logger.getLogger(name));
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}
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}

‎databricks-sdk-java/src/main/java/com/databricks/sdk/core/logging/LoggerFactory.java‎

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* creating any SDK client:
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*
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* <pre>{@code
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* LoggerFactory.setDefault(myCustomFactory);
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* LoggerFactory.setDefault(JulLoggerFactory.INSTANCE);
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* WorkspaceClient ws = new WorkspaceClient();
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* }</pre>
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*

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